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Sample records for platyrhynchos infected experimentally

  1. Genomic characterization of H14 subtype influenza A viruses in New World waterfowl and experimental infectivity in mallards Anas platyrhynchos

    Science.gov (United States)

    Ramey, Andy M.; Poulson, Rebecca L.; Gonzalez-Reiche, Ana S.; Perez, Daniel R.; Stalknecht, David E.; Brown, Justin D.

    2014-01-01

    Recent repeated isolation of H14 hemagglutinin subtype influenza A viruses (IAVs) in the New World waterfowl provides evidence to suggest that host and/or geographic ranges for viruses of this subtype may be expanding. In this study, we used genomic analyses to gain inference on the origin and evolution of H14 viruses in New World waterfowl and conducted an experimental challenge study in mallards (Anas platyrhynchos) to evaluate pathogenicity, viral replication, and transmissibility of a representative viral strain in a natural host species. Genomic characterization of H14 subtype IAVs isolated from New World waterfowl, including three isolates sequenced specifically for this study, revealed high nucleotide identity among individual gene segments (e.g. ≥95% shared identity among H14 HA gene segments). In contrast, lower shared identity was observed among internal gene segments. Furthermore, multiple neuraminidase subtypes were observed for H14 IAVs isolated in the New World. Gene segments of H14 viruses isolated after 2010 shared ancestral genetic lineages with IAVs isolated from wild birds throughout North America. Thus, genomic characterization provided evidence for viral evolution in New World waterfowl through genetic drift and genetic shift since purported introduction from Eurasia. In the challenge study, no clinical disease or lesions were observed among mallards experimentally inoculated with A/blue-winged teal/Texas/AI13-1028/2013(H14N5) or exposed via contact with infected birds. Titers of viral shedding for mallards challenged with the H14N5 IAV were highest at two days post-inoculation (DPI); however shedding was detected up to nine DPI using cloacal swabs. The distribution of viral antigen among mallards infected with H14N5 IAV was largely restricted to enterocytes lining the villi in the lower intestinal tract and in the epithelium of the bursa of Fabricius. Characterization of the infectivity of A/blue-winged teal/Texas/AI13-1028/2013(H14N5) in

  2. Genomic characterization of H14 subtype Influenza A viruses in new world waterfowl and experimental infectivity in mallards (Anas platyrhynchos.

    Directory of Open Access Journals (Sweden)

    Andrew M Ramey

    Full Text Available Recent repeated isolation of H14 hemagglutinin subtype influenza A viruses (IAVs in the New World waterfowl provides evidence to suggest that host and/or geographic ranges for viruses of this subtype may be expanding. In this study, we used genomic analyses to gain inference on the origin and evolution of H14 viruses in New World waterfowl and conducted an experimental challenge study in mallards (Anas platyrhynchos to evaluate pathogenicity, viral replication, and transmissibility of a representative viral strain in a natural host species. Genomic characterization of H14 subtype IAVs isolated from New World waterfowl, including three isolates sequenced specifically for this study, revealed high nucleotide identity among individual gene segments (e.g. ≥95% shared identity among H14 HA gene segments. In contrast, lower shared identity was observed among internal gene segments. Furthermore, multiple neuraminidase subtypes were observed for H14 IAVs isolated in the New World. Gene segments of H14 viruses isolated after 2010 shared ancestral genetic lineages with IAVs isolated from wild birds throughout North America. Thus, genomic characterization provided evidence for viral evolution in New World waterfowl through genetic drift and genetic shift since purported introduction from Eurasia. In the challenge study, no clinical disease or lesions were observed among mallards experimentally inoculated with A/blue-winged teal/Texas/AI13-1028/2013(H14N5 or exposed via contact with infected birds. Titers of viral shedding for mallards challenged with the H14N5 IAV were highest at two days post-inoculation (DPI; however shedding was detected up to nine DPI using cloacal swabs. The distribution of viral antigen among mallards infected with H14N5 IAV was largely restricted to enterocytes lining the villi in the lower intestinal tract and in the epithelium of the bursa of Fabricius. Characterization of the infectivity of A/blue-winged teal/Texas/AI13

  3. Differences in the detection of highly pathogenic avian influenza H5N1 virus in feather samples from 4-week-old and 24-week-old infected Pekin ducks (Anas platyrhynchos var. domestica).

    Science.gov (United States)

    Aiello, Roberta; Beato, Maria Serena; Mancin, Marzia; Rigoni, Michela; Tejeda, Aurora Romero; Maniero, Silvia; Capua, Ilaria; Terregino, Calogero

    2013-08-30

    Previous studies have reported the detection of H5N1 HPAI virus in feathers from ducks naturally and experimentally infected and suggested that feather calami (FC) could be used as diagnostic samples for the early detection of H5N1 HPAI infections. Ducks are readily infected with H5N1 HPAI viruses although the development of clinical signs and deaths were reported as age-related with younger birds being more susceptible. The correlation between age and virus localisation in FC of infected ducks has not been studied to date. In the present study juvenile (4-week-old) and adult (24-week-old) Pekin ducks (Anas platyrhynchos var. domestica) were infected experimentally with a clade 2.2 H5N1 HPAI virus (A/duck/Nigeria/1071-23/2007). Tracheal (Tr) and cloacal (Cl) swabs and FC were collected at 3, 5, 7 and 10 days post infection and tested by RRT-PCR and a double antibody sandwich-ELISA (DAS-ELISA) developed in house. Virus was detected in swabs and FC of challenged ducks with a higher rate of detection in juvenile ducks. In this age group virus was detected over a longer period of time in FC compared to swabs. Our study showed that FC samples collected from young ducks are a valid diagnostic specimen for H5N1 HPAI virus detection. The DAS-ELISA on FC proved to be a suitable alternative diagnostic test when molecular and/or virus isolation techniques are not available therefore it could be useful in the diagnosis of H5N1 HPAI infections in under-resourced countries. Copyright © 2013 Elsevier B.V. All rights reserved.

  4. GAMBARAN PROFIL DARAH ITIK PEKING (ANAS PLATYRHYNCHOS SETELAH DIBERIKAN EKSTRAK AKUADES DAUN KEDONDONG PAGAR (LANNEA COROMANDELICA

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    Safrida Safrida

    2017-10-01

    Full Text Available ABSTRACTThis study was designed to determine the effect aqueous extract of Lannea coromandelica leaf at concentrations of erythrocytes and leukocytes in peking duck (Anas platyrhynchos. Experimental design used was Completely Randomized Design (CRD consisted of 3 experimental treatments, each consisted of 8 ducks i.e., P0 (control, P1 (given aqueous extract of Lannea coromandelica leaf as much as 780 mg / mL / day / kg body weight, P2 (given aqueous extract of Lannea coromandelica leaf as much as 1560 mg / mL / day / kg body weight. Data were analyzed using analysis of variance (ANOVA. The results showed that the aqueous extract of Lannea coromandelica significant effect (p <0.01 in concentrations of erythrocytes peking duck, but had no effect (P>  0.01 in concentrations of the leukocytes. Average erythrocytes in all treatments, 2081667-2300000 per mm 3. The average number of leukocytes in all treatments, 23175-23500 per mm3. It was concluded that the aqueous extract of Lannea coromandelica leaf have effect on the increase concentrations of erythrocytes peking duck (Anas platyrhynchos.

  5. Sanguinicola platyrhynchi n. sp. (Digenea: Sanguinicolidae parasite of visceral cavity of Hemisorubim platyrhynchos (Valenciennes, 1840 (Pisces: Pimelodidae from the floodplain of the upper Paraná River, Brazil

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    GUIDELLI G. M.

    2002-01-01

    Full Text Available A new species is of the genus Sanguinicola Plehn, 1905 described, Sanguinicola platyrhynchi n. sp., digenetic parasite of visceral cavity of Hemisorubim platyrhynchos (Valenciennes, 1840 from the floodplain of the upper Paraná River, Brazil. The species has been thus included because of the presence of separate dorsal genital pores, while differing from other species of the same genus mainly in digestive apparatus features, genital pore position, and infection site. Emendation of generic diagnosis is included.

  6. Susceptibility of Muscovy (Cairina Moschata) and mallard ducks (Anas Platyrhynchos) to experimental infections by different genotypes of H5N1 avian influenza viruses

    DEFF Research Database (Denmark)

    Phuong, Do Quy; Dung, Nguyen Tien; Jørgensen, Poul Henrik

    2011-01-01

    exposed to infection with H5N1. To do this, an experimental study on infections with different genotypes of H5N1 in mallards and Muscovy ducks have been conducted, where it was found that the mortality of the inoculated Muscovy ducks was at least 80%, regardless of the virus strain employed. In contrast...... in the brain. Due to their high susceptibility, it is unlikely that Muscovy ducks act as a silent reservoir. The virus strains used in this study, to a certain degree, differed in their virulence properties to the bird species in question.......It is a fact that in Viet Nam, Muscovy ducks are raised in large populations (approximately 8 million), usually kept in small flocks together with mallards and chickens. As a result, it is a great concern for epidemiologists to elucidate possible differences in relation to these species being...

  7. Pathogenesis of highly pathogenic avian influenza A/turkey/Turkey/1/2005 H5N1 in Pekin ducks (Anas platyrhynchos) infected experimentally.

    Science.gov (United States)

    Löndt, Brandon Z; Nunez, Alejandro; Banks, Jill; Nili, Hassan; Johnson, Linda K; Alexander, Dennis J

    2008-12-01

    Asian H5N1 (hereafter referred to as panzootic H5N1) highly pathogenic avian influenza (HPAI) virus has caused large numbers of deaths in both poultry and wild-bird populations. Recent isolates of this virus have been reported to cause disease and death in commercial ducks, which has not been seen with other HPAI viruses. However, little is known about either the dissemination of this H5N1 within the organs or the cause of death in infected ducks. Nineteen 4-week-old Pekin ducks were infected with 10(6.7) median egg infectious doses of HPAI A/turkey/Turkey/1/05 (H5N1, clade 2.2) in 0.1ml via the intranasal and intraocular routes. Cloacal and oropharyngeal swabs were taken daily before three animals were selected randomly and killed humanely for postmortem examination, when samples of tissues were taken for real-time reverse transcriptase-polymerase chain reaction, histopathological examination and immunohistochemistry. Clinical signs were first observed 4 days post infection (d.p.i.) and included depression, reluctance to feed, in-coordination and torticollis resulting in the death of all the birds remaining on 5d.p.i. Higher levels of virus shedding were detected from oropharyngeal swabs than from cloacal swabs. Real-time reverse transcriptase-polymerase chain reaction and immunohistochemistry identified peak levels of virus at 2d.p.i. in several organs. In the spleen, lung, kidney, caecal tonsils, breast muscle and thigh muscle the levels were greatly reduced at 3d.p.i. However, the highest viral loads were detected in the heart and brain from 3d.p.i. and coincided with the appearance of clinical signs and death. Our experimental results demonstrate the systemic spread of this HPAI H5N1 virus in Pekin ducks, and the localization of virus in the brain and heart tissue preceding death.

  8. Influenza virus in a natural host, the mallard: experimental infection data.

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    Elsa Jourdain

    Full Text Available Wild waterfowl, particularly dabbling ducks such as mallards (Anas platyrhynchos, are considered the main reservoir of low-pathogenic avian influenza viruses (LPAIVs. They carry viruses that may evolve and become highly pathogenic for poultry or zoonotic. Understanding the ecology of LPAIVs in these natural hosts is therefore essential. We assessed the clinical response, viral shedding and antibody production of juvenile mallards after intra-esophageal inoculation of two LPAIV subtypes previously isolated from wild congeners. Six ducks, equipped with data loggers that continually monitored body temperature, heart rate and activity, were successively inoculated with an H7N7 LPAI isolate (day 0, the same H7N7 isolate again (day 21 and an H5N2 LPAI isolate (day 35. After the first H7N7 inoculation, the ducks remained alert with no modification of heart rate or activity. However, body temperature transiently increased in four individuals, suggesting that LPAIV strains may have minor clinical effects on their natural hosts. The excretion patterns observed after both re-inoculations differed strongly from those observed after the primary H7N7 inoculation, suggesting that not only homosubtypic but also heterosubtypic immunity exist. Our study suggests that LPAI infection has minor clinically measurable effects on mallards and that mallard ducks are able to mount immunological responses protective against heterologous infections. Because the transmission dynamics of LPAIVs in wild populations is greatly influenced by individual susceptibility and herd immunity, these findings are of high importance. Our study also shows the relevance of using telemetry to monitor disease in animals.

  9. Cytogenetics of the Porthole Shovelnose Catfish, Hemisorubim platyrhynchos (Valenciennes, 1840) (Siluriformes, Pimelodidae), a widespread species in South American rivers

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    Swarça, Ana Cláudia; Sanchez, Sebastian; Dias, Ana Lucia; Fenocchio, Alberto Sergio

    2013-01-01

    Abstract Hemisorubim platyrhynchos is a medium- to large-sized pimelodid catfish distributed along several river basins of the Neotropical Region, noteworthy for representing an important fishery source. In this work, Hemisorubim platyrhynchos from three isolated populations were cytogenetically analyzed. The karyotype shows a diploid number of 2n=56 chromosomes comprising 22m, 16sm, 10st, 8a (FN=104). NORs detected by AgNO3 were located in the terminal regions of the short arm of a st chromosome pair, as confirmed by CMA3 and FISH using an 18S rDNA probe. C-banding revealed a small amount of heterochromatin in chromosomes, including the NORs, and one biarmed pair that showed conspicuous positive bands on both arms. This fact was also evidenced when using other banding techniques, such as RE (AluI), and indicates that this pair constitutes a species-specific cytogenetic marker. PMID:24260693

  10. Mitochondrial D-loop analysis for uncovering the population structure and genetic diversity among the indigenous duck (Anas platyrhynchos) populations of India.

    Science.gov (United States)

    Gaur, Uma; Tantia, Madhu Sudan; Mishra, Bina; Bharani Kumar, Settypalli Tirumala; Vijh, Ramesh Kumar; Chaudhury, Ashok

    2018-03-01

    The indigenous domestic duck (Anas platyrhynchos domestica) which is domesticated from Mallard (Anas platyrhynchos) contributes significantly to poor farming community in coastal and North Eastern regions of India. For conservation and maintenance of indigenous duck populations it is very important to know the existing genetic diversity and population structure. To unravel the population structure and genetic diversity among the five indigenous duck populations of India, the mitochondrial D-loop sequences of 120 ducks were analyzed. The sequence analysis by comparison of mtDNA D-loop region (470 bp) of five Indian duck populations revealed 25 mitochondrial haplotypes. Pairwise F ST value among populations was 0.4243 (p land birds revealed introgression of the out group breed Khaki Campbell, which is used for breed improvement programs in India. The observations revealed very less selection and a single matrilineal lineage of indigenous domestic ducks.

  11. Infectivity of Trichinella papuae for experimentally infected red foxes (Vulpes vulpes)

    DEFF Research Database (Denmark)

    Webster, P.; Malakauskas, A.; Kapel, C. M O

    2002-01-01

    To evaluate infectivity for carnivores as well as other biological characteristics of the newly described Trichinella papuae, eight red foxes were experimentally infected with the parasite. Five weeks after inoculation, T. papuae larvae were recovered from nine different muscle types. The larvae...

  12. Disease dynamics and bird migration-linking mallards Anas platyrhynchos and subtype diversity of the influenza a virus in time and space

    NARCIS (Netherlands)

    G. Gunnarsson (Gunnar); N. Latorre-Margalef (Neus); K.A. Hobson (Keith); S.L. van Wilgenburg (Steven); J. Elmberg (Johan); B. Olsen (Björn); R.A.M. Fouchier (Ron); J. Waldenström (Jonas)

    2012-01-01

    textabstractThe mallard Anas platyrhynchos is a reservoir species for influenza A virus in the northern hemisphere, with particularly high prevalence rates prior to as well as during its prolonged autumn migration. It has been proposed that the virus is brought from the breeding grounds and

  13. Lead level in mallard (Anas platyrhynchos

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    Ioan Macinic

    2012-12-01

    Full Text Available The study was carried out on a hunting ground belonging to AJVPS Arad, county Arad. Lead (Pb was determined in Mallard (Anas platyrhynchos tissues (muscles and organs (liver, kidneys to see the contamination level of this tissues and organs and also the impact on humans health because in our days more and more wild game meat take a increasing percentage in humans food ratio. The Mallard is one of the most widespread duck species. Mallard has 50-62 cm length, 800-1400 g weight and lives about 11 years. It prefers rivers and shallow pounds with a lot of reed. It is a migratory species that is flying long distances to find food and unfrozen water, so it is a exposed to lead contamination that is under dust form in atmosphere. But another reason why lead level in Mallard can be higher that in other flying specie (pheasant, woodcock, quail, and pigeons are the lead shot shells that are used for duck hunting. It is known that the ducks can ingest these lead shot shells and so they are often exposed to lead intoxications. This is why in our days more ammunition for waterfowl are steel made or different type of alloys. Lead is known to be one of the most common pollutants with a large range of effects on human health: lead affects nervous system, digestive tract, kidneys, bones, enzymes. Lead has also mutagenic effect, carcinogenic effect, teratogenic effect.

  14. Blood biochemistry responses of chickens experimentally infected ...

    African Journals Online (AJOL)

    This study investigated the blood biochemistry responses of cockerels experimentally infected with a velogenic Newcastle disease virus (NDV) strain, KUDU 113. One hundred Isa white cockerels were used for the study. The cockerels were obtained at day-old and randomly divided into groups A- vaccinated and infected, ...

  15. Sublethal effects of cadmium ingestion on mallard ducks. [Anas platyrhynchos

    Energy Technology Data Exchange (ETDEWEB)

    Di Giulio, R T; Scanlon, P F

    1984-11-01

    Juvenile mallard (Anas platyrhynchos) drakes were fed diets containing 0, 50, 150, or 450 ppM cadmium for 42 +/- 1 days in order to assess the impacts of cadmium ingestion on energy metabolism and tissue metal concentrations in this species. Most significant effects on energy metabolism were observed only in the 450 ppM group which displayed reduced body and liver weights, increased kidney weights, reduced liver aldolase activity, increased plasma concentrations of uric acid, decreased plasma triiodothyronine concentrations, and elevated adrenal weights and adrenal corticosterone concentrations. Ducks in the 150 ppM group displayed increased adrenal and kidney weights and elevated plasma nonesterified fatty acid concentrations. Among all treatments, increased cadmium and zinc concentrations in both livers and kidneys were dose-related; a similar trend was observed for copper concentrations in kidneys but not livers. Cadmium interference with carbohydrate metabolism in similar studies with mammals was more severe than that observed in mallards in the present study. 52 references, 6 tables.

  16. The impact of using lead pellets on lead contamination of mallards (Anas platyrhynchos in the Czech Republic

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    Zdeňka Hutařová

    2013-01-01

    Full Text Available The aim of the study was to assess the degree of lead contamination in mallards in the Czech Republic as a result of using lead shots for wildfowling. Two sites used for mallard hunting were chosen, namely a flood-control reservoir in Moravia and a small fishpond in Bohemia. Lead concentrations were determined in the tissues of 20 mallards (Anas platyrhynchos raised at those standing open water sites (n = 10 at each site and killed there during the autumn hunting season with a steel shot. Control groups were made up of 20 mallards from the same breeding facility as experimental groups but raised in an enclosure without access to water (n = 10 at each site. Lead concentrations were determined in selected tissues (breast muscle, heart, liver, gizzard, kidney, feathers - quill base, lung, brain and humerus by high resolution continuum source atomic absorption spectrometry. The results showed elevated lead concentrations in all tissues of mallards compared with control in the reservoir in Southern Moravia. The highest lead concentrations (mg/kg were found in the humerus (14.254 ± 4.525 and 5.083 ± 0.748 for experimental and control mallards, respectively. In contrast, lead concentrations in mallards from small fishpond in Southern Bohemia were lower compared to control. Similarly, the highest lead concentrations were found in the humerus (2.219 ± 0.349 and 8.930 ± 1.012 for experimental and control mallards, respectively. This study extends very limited information about lead contamination of wild ducks in the Czech Republic in connection with hunting activities.

  17. Infections in orthopaedic surgery : clinical and experimental studies

    NARCIS (Netherlands)

    Vogely, Henri Charles

    2000-01-01

    The diagnostic difficulties, variability in outcome and the heterogeinity of the problem of orthopaedic infections stimulated the author to a study of the literature, and several clinical and experimental studies. The diagnosis prosthesis-related infection can only be reached with an acceptable

  18. Morfología e histoquímica del hígado del pez carnívoro Hemisorubim Platyrhynchos

    OpenAIRE

    Faccioli, Claudemir Kuhn [UNESP; Chedid, Renata Alari [UNESP; Bombonato, Maria Terezinha Siqueira [UNESP; Vicentini, Carlos Alberto [UNESP; Vicentini, Irene Bastos Franceschini [UNESP

    2014-01-01

    The aim of this study was to characterize the normal structure of the liver of Hemisorubim platyrhynchos, a carnivorous freshwater catfish found in Neotropical region, using gross anatomy, histology and histochemistry. Anatomically, the liver presents C-shaped and only two lobes: smaller right and bigger left. The gallbladder is located in right lobe and shows elongated shaped. Histological analysis demonstrated that the hepatic parenchyma is made of two hepatocytes plates surrounded by sinus...

  19. Novel duck parvovirus identified in Cherry Valley ducks (Anas platyrhynchos domesticus), China.

    Science.gov (United States)

    Li, Chuanfeng; Li, Qi; Chen, Zongyan; Liu, Guangqing

    2016-10-01

    An unknown infectious disease in Cherry Valley ducks (Anas platyrhynchos domesticus) characterized by short beak and strong growth retardation occurred in China during 2015. The causative agent of this disease, tentatively named duck short beak and dwarfism syndrome (DSBDS), as well as the evolutionary relationships between this causative agent and all currently known avian-origin parvoviruses were clarified by virus isolation, transmission electron microscope (TEM) observation, analysis of nuclear acid type, (RT-)PCR identification, whole genome sequencing, and NS1 protein sequences-based phylogenetic analyses. The results indicated that the causative agent of DSBDS is closely related with the goose parvovirus-like virus, which is divergent from all currently known avian-origin parvoviruses and should be a novel duck parvovirus (NDPV). Copyright © 2016 Elsevier B.V. All rights reserved.

  20. Normal xeroradiographic and radiographic anatomy of the mallard duck (Anas platyrhynchos) with reference to other anserine species

    Energy Technology Data Exchange (ETDEWEB)

    Smith, B. J. [North Carolina State University, Raleigh (United States); Smith, S. A.

    1991-03-15

    he purpose of this study was to provide a reference for xeroradiographic and conventional radiographic anatomy of the mallard duck (Anas platyrhynchos) as a representative of the avian Order Anseriformes. The head, body, wing, and pelvic limb of three adult birds were radiographed using xeroradiographic and conventional radiographic techniques. Nine xeroradiographs and their corresponding conventional radiographs were selected, and the xeroradiographs labeled to illustrate normal anatomy. Selected views of other anseriform species were included to illustrate certain anatomical features unique to those species.

  1. Normal xeroradiographic and radiographic anatomy of the mallard duck (Anas platyrhynchos) with reference to other anserine species

    International Nuclear Information System (INIS)

    Smith, B.J.; Smith, S.A.

    1991-01-01

    he purpose of this study was to provide a reference for xeroradiographic and conventional radiographic anatomy of the mallard duck (Anas platyrhynchos) as a representative of the avian Order Anseriformes. The head, body, wing, and pelvic limb of three adult birds were radiographed using xeroradiographic and conventional radiographic techniques. Nine xeroradiographs and their corresponding conventional radiographs were selected, and the xeroradiographs labeled to illustrate normal anatomy. Selected views of other anseriform species were included to illustrate certain anatomical features unique to those species

  2. Complete Genome Sequence of a Virulent Newcastle Disease Virus Strain Isolated from a Clinically Healthy Duck (Anas platyrhynchos domesticus) in Pakistan

    Science.gov (United States)

    Wajid, Abdul; Rehmani, Shafqat F.; Wasim, Muhammad; Basharat, Asma; Bibi, Tasra; Arif, Saima; Dimitrov, Kiril M.

    2016-01-01

    Here, we report the complete genome sequence of a virulent Newcastle disease virus (vNDV) strain, duck/Pakistan/Lahore/AW-123/2015, isolated from apparently healthy laying ducks (Anas platyrhynchos domesticus) from the province of Punjab, Pakistan. The virus has a genome length of 15,192 nucleotides and is classified as member of subgenotype VIIi, class II. PMID:27469959

  3. Complete Genome Sequence of a Virulent Newcastle Disease Virus Strain Isolated from a Clinically Healthy Duck (Anas platyrhynchos domesticus) in Pakistan

    OpenAIRE

    Wajid, Abdul; Rehmani, Shafqat F.; Wasim, Muhammad; Basharat, Asma; Bibi, Tasra; Arif, Saima; Dimitrov, Kiril M.; Afonso, Claudio L.

    2016-01-01

    Here, we report the complete genome sequence of a virulent Newcastle disease virus (vNDV) strain, duck/Pakistan/Lahore/AW-123/2015, isolated from apparently healthy laying ducks (Anas platyrhynchos domesticus) from the province of Punjab, Pakistan. The virus has a genome length of 15,192 nucleotides and is classified as member of subgenotype VIIi, class II.

  4. Quantification of HTLV-I proviral load in experimentally infected rabbits

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    Kindt Thomas J

    2005-05-01

    Full Text Available Abstract Background Levels of proviral load in HTLV-1 infected patients correlate with clinical outcome and are reasonably prognostic. Adaptation of proviral load measurement techniques is examined here for use in an experimental rabbit model of HTLV-1 infection. Initial efforts sought to correlate proviral load with route and dose of inoculation and with clinical outcome in this model. These methods contribute to our continuing goal of using the model to test treatments that alleviate virus infection. Results A real-time PCR assay was used to measure proviral load in blood and tissue samples from a series of rabbits infected using HTLV-1 inocula prepared as either cell-free virus particles, infected cells or blood, or by naked DNA injection. Proviral loads from asymptomatically infected rabbits showed levels corresponding to those reported for human patients with clinically silent HTLV-1 infections. Proviral load was comparably increased in 50% of experimentally infected rabbits that developed either spontaneous benign or malignant tumors while infected. Similarly elevated provirus was found in organs of rabbits with experimentally induced acute leukemia/lymphoma-like disease. Levels of provirus in organs taken at necropsy varied widely suggesting that reservoirs of infections exist in non-lymphoid organs not traditionally thought to be targets for HTLV-1. Conclusion Proviral load measurement is a valuable enhancement to the rabbit model for HTLV-1 infection providing a metric to monitor clinical status of the infected animals as well as a means for the testing of treatment to combat infection. In some cases proviral load in blood did not reflect organ proviral levels, revealing a limitation of this method for monitoring health status of HTLV-1 infected individuals.

  5. Pathogenesis of natural and experimental Pseudorabies virus infections in dogs.

    Science.gov (United States)

    Zhang, Letian; Zhong, Cheng; Wang, Jushi; Lu, Zijie; Liu, Lei; Yang, Wanlian; Lyu, Yanli

    2015-03-18

    Since late 2011, cases of suspected canine pseudorabies have increased in north China with the outbreak of swine pseudorabies in the same area, but the pathogenesis of canine Pseudorabies virus (PRV) infections in China is poorly understood. In this study, we investigated the pathogenesis of canine pseudorabies. The pathological changes in 13 dogs that died of natural PRV infections (confirmed by pathogen detection) during 2011-2013 in Beijing were evaluated. An experimental study was also conducted in which healthy adult beagle dogs were administered PRV isolate BJ-YT by subcutaneous injection. The dog tissues were subjected to gross and microscopic examinations and immunohistochemical analysis and the dogs' serum cardiac troponin-I (cTn-I) was measured. Systemic hemorrhage and/or congestion were the most marked pathological changes in both the naturally and experimentally PRV-infected dogs. Macroscopically, the major lesions consisted of petechiae and ecchymoses in both the endocardium and epicardium, thrombi in the mitral valves, hemorrhage in the lungs and thymus, and incomplete contraction of the spleen. Microscopically, the major histopathological findings were systemic hemorrhage and congestion, nonsuppurative ganglioneuritis (in the experimentally infected dogs, unexamined in the naturally PRV-infected dogs), brainstem encephalitis (in the naturally infected dogs), necrosis or exudation in the myocardium, and lymphoid depletion in many lymphoid organs and tissues. Viral antigens were only detected in the brainstems and peripheral ganglia of the infected dogs. Serum cTn-I was significantly higher in the experimentally PRV-infected dogs with myocardial lesions than in the dogs without myocardial lesions. Based on these results, we conclude that virally induced systemic hemorrhage, peripheral nervous system pathology, and/or cardiac injury can individually or collectively cause death in PRV-infected dogs. The respiratory signs of the disease are attributed to

  6. Primary peak and chronic malaria infection levels are correlated in experimentally infected great reed warblers.

    Science.gov (United States)

    Asghar, Muhammad; Westerdahl, Helena; Zehtindjiev, Pavel; Ilieva, Mihaela; Hasselquist, Dennis; Bensch, Staffan

    2012-09-01

    Malaria parasites often manage to maintain an infection for several months or years in their vertebrate hosts. In humans, rodents and birds, most of the fitness costs associated with malaria infections are in the short initial primary (high parasitaemia) phase of the infection, whereas the chronic phase (low parasitaemia) is more benign to the host. In wild birds, malaria parasites have mainly been studied during the chronic phase of the infection. This is because the initial primary phase of infection is short in duration and infected birds with severe disease symptoms tend to hide in sheltered places and are thus rarely caught and sampled. We therefore wanted to investigate the relationship between the parasitaemia during the primary and chronic phases of the infection using an experimental infection approach. We found a significant positive correlation between parasitaemia in the primary peak and the subsequent chronic phase of infection when we experimentally infected great reed warblers (Acrocephalus arundinaceus) with Plasmodium ashfordi. The reason for this association remains to be understood, but might arise from individual variation in exoerythrocytic parasite reservoirs in hosts, parasite antigenic diversity and/or host genetics. Our results suggest that the chronic phase parasitaemia can be used to qualitatively infer the parasitaemia of the preceding and more severe primary phase, which is a very important finding for studies of avian malaria in wild populations.

  7. Primary infection protects pigs against re-infection with Lawsonia intracellularis in experimental challenge studies

    DEFF Research Database (Denmark)

    Riber, Ulla; Hvass, Henriette Cordes; Boutrup, Torsten Snogdal

    2011-01-01

    In two separate trials previous termpigsnext term were experimentally infected with previous termLawsonia intracellularisnext term at 5–6 weeks of age followed by antibiotic treatment and resolution of the previous termprimary infection and then renext term-inoculated at 12–13 weeks of age. A tre...

  8. Oxidative stress in rats experimentally infected by Sporothrix schenckii.

    Science.gov (United States)

    Castro, Verônica S P; Da Silva, Aleksandro S; Thomé, Gustavo R; Wolkmer, Patrícia; Castro, Jorge L C; Costa, Márcio M; Graça, Dominguita L; Oliveira, Daniele C; Alves, Sydney H; Schetinger, Maria R C; Lopes, Sonia T A; Stefani, Lenita M; Azevedo, Maria I; Baldissera, Matheus D; Andrade, Cinthia M

    2017-06-01

    The aim of this study was to evaluate whether oxidative stress occurs in rats experimentally infected by Sporothrix schenckii, and its possible effect on disease pathogenesis. Thirty rats were divided into two groups: the group A (uninfected, n = 18) and the group B (infected by S. schenckii, n=21). Blood samples were collected on days 15, 30 and 40 post-infection (PI). At each sampling time, six rats of the group A, and seven of the group B were bled. TBARS (thiobarbituric acid reactive substances) levels in serum samples were measured to evaluate lipid peroxidation. In addition, catalase (CAT) and superoxide dismutase (SOD) activities, known as biomarkers of antioxidants levels, were verified in whole blood. Seric pro-inflammatory cytokine levels were measured (IFN-γ, TNF-α, and IL-6), which showed that these inflammatory mediators were at higher levels in the infected rats (P sporotrichosis showed significantly higher (p sporotrichosis is a likely mechanism for redox imbalance, and consequently cause the oxidative stress in experimentally infected rats. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Humid microclimates within the plumage of mallard ducks (Anas platyrhynchos) can potentially facilitate long distance dispersal of propagules

    Science.gov (United States)

    Coughlan, Neil E.; Kelly, Tom C.; Davenport, John; Jansen, Marcel A. K.

    2015-05-01

    Birds as carriers of propagules are major agents in the dispersal of plants, animals, fungi and microbes. However, there is a lack of empirical data in relation to bird-mediated, epizoochorous dispersal. The microclimate found within the plumage likely plays a pivotal role in survival during flight conditions. To investigate the potential of epizoochory, we have analysed the microclimatic conditions within the plumage of mallard ducks (Anas platyrhynchos). Under similar ambient conditions of humidity and temperature, a sample of mallards showed a consistent microclimatic regime with variation across the body surface. The highest (mean) temperature and specific humidity occurred between feathers of the postpatagium. The lowest humidity was found between feathers of the centre back and the lowest temperature in the crissum. Observed differences in plumage depth and density, and distance from the skin, are all likely to be determining factors of microclimate condition. Specific humidity found within the plumage was on average 1.8-3.5 times greater than ambient specific humidity. Thus, the plumage can supply a microclimate buffered from that of the exterior environment. Extrapolating survival data for Lemna minor desiccation at various temperature and humidity levels to the measured plumage microclimatic conditions of living birds, survival for up to 6 h can be anticipated, especially in crissum, crural and breast plumage. The results are discussed in the context of potential long distance epizoochorous dispersal by A. platyrhynchos and similar species.

  10. Detection of toxoplasma gondii antigens in sera from experimentally infected mice

    International Nuclear Information System (INIS)

    Shojaee, S.; Keshavarz, H.; Rezaian, M.; Mohebali, M.

    2007-01-01

    Detection of Toxoplasma antigen in serum of mice by Immunoblotting. strain. IgG isolated from rabbits that were immunized with T. gondii Immunoblotting was performed to detect T. gondii antigens in sera of mice. Serum samples from mice experimentally infected with T. gondii RH strain. The value of Immunoblotting in diagnosis of toxoplasmosis in acute stage of infection. The antigen bands detected in serum sample of mice were experimentally infected with T. gondii tachyzoite in immunoblotting. Six bands demonstrated on seventh post infection day six bands were identified. Similarly on sixth day four bands, on day five three bands and on fourth post infection day two bands were identified. No band was detected in control group sera. Immunoblotting is a sensitive method for diagnosis of acute stage of toxoplasmosis. (author)

  11. Avian influenza infection alters fecal odor in mallards.

    Directory of Open Access Journals (Sweden)

    Bruce A Kimball

    Full Text Available Changes in body odor are known to be a consequence of many diseases. Much of the published work on disease-related and body odor changes has involved parasites and certain cancers. Much less studied have been viral diseases, possibly due to an absence of good animal model systems. Here we studied possible alteration of fecal odors in animals infected with avian influenza viruses (AIV. In a behavioral study, inbred C57BL/6 mice were trained in a standard Y-maze to discriminate odors emanating from feces collected from mallard ducks (Anas platyrhynchos infected with low-pathogenic avian influenza virus compared to fecal odors from non-infected controls. Mice could discriminate odors from non-infected compared to infected individual ducks on the basis of fecal odors when feces from post-infection periods were paired with feces from pre-infection periods. Prompted by this indication of odor change, fecal samples were subjected to dynamic headspace and solvent extraction analyses employing gas chromatography/mass spectrometry to identify chemical markers indicative of AIV infection. Chemical analyses indicated that AIV infection was associated with a marked increase of acetoin (3-hydroxy-2-butanone in feces. These experiments demonstrate that information regarding viral infection exists via volatile metabolites present in feces. Further, they suggest that odor changes following virus infection could play a role in regulating behavior of conspecifics exposed to infected individuals.

  12. Infectivity and temperature tolerance of non-encapsulating Trichinella zimbabwensis in experimentally infected red foxes (Vulpes vulpes)

    DEFF Research Database (Denmark)

    Hurníková, Z.; Dubinský, P.; Mukaratirwa, S.

    2004-01-01

    The non-encapsulating Trichinella zimbabwensis was evaluated for infectivity in red foxes (Vulpes vulpes), the larval distribution and cold tolerance in fox muscle tissue. Six red foxes were experimentally infected with T. zimbabwensis larvae. Five weeks after inoculation, muscle larvae were...... recovered from 9 different muscle types using artificial digestion method. The establishment of infection in all infected red foxes demonstrated the ability of T. zimbabwensis to complete its life cycle in a carnivore mammal host. The larvae recovered from fox muscle tissue were infective to mice, they have...

  13. Experimental porcine cysticercosis using infected beetles with Taenia solium eggs.

    Science.gov (United States)

    Gomez-Puerta, Luis A; Garcia, Hector H; Gonzalez, Armando E

    2018-07-01

    Beetles are intermediate hosts for human and animal parasites, and several beetle species have been shown to carry Taenia eggs. An experimental porcine cysticercosis infection model was developed using beetles (Ammophorus rubripes) infected with Taenia solium eggs and then using these beetles for oral pig challenge. A total of 18 three months-old Landrace pigs were divided in four groups. Pigs from groups 1, 2, and 3 (n = 6 pigs per group) were challenged with one, three, and six beetles infected with T. solium eggs, containing approximately 52, 156 or 312 eggs respectively. Pigs were necropsied 12 weeks after infection to assess the presence of T. solium metacestode. Porcine cysticercosis by T. solium was produced in 17 out of 18 pigs (94.4%) challenged with infected beetles, all infected pigs had viable cysts. Only one pig from group 1 was negative to the presence of cysts. The median number of metacestodes per pig in groups 1, 2, and 3 were 2 (range 0-71), 26 (range 5-33) and 40 cysts (range 4-111), respectively. Experimental porcine cysticercosis infection is consistently obtained using beetles as mechanical vectors for T. solium eggs. Copyright © 2018 Elsevier B.V. All rights reserved.

  14. Humoral immune response and spreading of Encephalitozoon cuniculi infection in experimentally infected ponies

    Czech Academy of Sciences Publication Activity Database

    Wagnerová, Pavla; Sak, Bohumil; Květoňová, Dana; Maršálek, M.; Langerová, I.; Kváč, Martin

    2013-01-01

    Roč. 197, 1-2 (2013), s. 1-6 ISSN 0304-4017 Institutional support: RVO:60077344 Keywords : Ponies * Encephalitozoon cuniculi genotype II * PCR * Antibodies * Experimental infection Subject RIV: EC - Immunology Impact factor: 2.545, year: 2013

  15. Effects of Experimental Sarcocystis neurona-Induced Infection on Immunity in an Equine Model

    Directory of Open Access Journals (Sweden)

    S. Rochelle Lewis

    2014-01-01

    Full Text Available Sarcocystis neurona is the most common cause of Equine Protozoal Myeloencephalitis (EPM, affecting 0.5–1% horses in the United States during their lifetimes. The objective of this study was to evaluate the equine immune responses in an experimentally induced Sarcocystis neurona infection model. Neurologic parameters were recorded prior to and throughout the 70-day study by blinded investigators. Recombinant SnSAG1 ELISA for serum and CSF were used to confirm and track disease progression. All experimentally infected horses displayed neurologic signs after infection. Neutrophils, monocytes, and lymphocytes from infected horses displayed significantly delayed apoptosis at some time points. Cell proliferation was significantly increased in S. neurona-infected horses when stimulated nonspecifically with PMA/I but significantly decreased when stimulated with S. neurona compared to controls. Collectively, our results suggest that horses experimentally infected with S. neurona manifest impaired antigen specific response to S. neurona, which could be a function of altered antigen presentation, lack of antigen recognition, or both.

  16. Effects of Experimental Sarcocystis neurona-Induced Infection on Immunity in an Equine Model.

    Science.gov (United States)

    Lewis, S Rochelle; Ellison, Siobhan P; Dascanio, John J; Lindsay, David S; Gogal, Robert M; Werre, Stephen R; Surendran, Naveen; Breen, Meghan E; Heid, Bettina M; Andrews, Frank M; Buechner-Maxwell, Virginia A; Witonsky, Sharon G

    2014-01-01

    Sarcocystis neurona is the most common cause of Equine Protozoal Myeloencephalitis (EPM), affecting 0.5-1% horses in the United States during their lifetimes. The objective of this study was to evaluate the equine immune responses in an experimentally induced Sarcocystis neurona infection model. Neurologic parameters were recorded prior to and throughout the 70-day study by blinded investigators. Recombinant SnSAG1 ELISA for serum and CSF were used to confirm and track disease progression. All experimentally infected horses displayed neurologic signs after infection. Neutrophils, monocytes, and lymphocytes from infected horses displayed significantly delayed apoptosis at some time points. Cell proliferation was significantly increased in S. neurona-infected horses when stimulated nonspecifically with PMA/I but significantly decreased when stimulated with S. neurona compared to controls. Collectively, our results suggest that horses experimentally infected with S. neurona manifest impaired antigen specific response to S. neurona, which could be a function of altered antigen presentation, lack of antigen recognition, or both.

  17. [Experimental infection of the gerbil (Meriones unguiculatus) by Colombian isolates of Giardia duodenalis].

    Science.gov (United States)

    Arévalo, Adriana; Duque, Sofía; Nicholls, Rubén Santiago

    2005-09-01

    Natural and experimental Giardia infections have been reported from bovines, equines, goats, canines, felines and rodents such as mice, rats and gerbils. The latter have provided successful animal models for Giardia duodenalis and Giardia muris experimental infections. The gerbil model was used to establish the pattern of infection of Colombian Giardia human isolates. Giardia cysts were obtained from stool specimens of symptomatic giardiasis patients by means of sucrose-percoll gradients. Animal inoculation was performed by gastric intubation and injection with 5 x 10(3) Giardia cysts. The course of infection was established by counting cysts every day and trophozoites weekly throughout a period of 30 days. The pattern of cyst excretion was found to be intermittent. Cysts were released during the second and third weeks of infection but not during the first or fourth weeks. The mean minimal number of cysts released per 2-hr collection period was 79 and the mean maximum number was 17,943. Colonization of the small intestine by trophozoites was observed with a mean number ranging from 15,000 to 6,577,778 trophozoites/ml. Gerbils inoculated with G. duodenalis isolates obtained from geographical areas outside Colombia resolved the infection between 86 and 114 days after infection, whereas gerbils infected with Colombian G. duodenalis isolates resolved the infection at 30 days. The gerbil proved to be a good animal model for experimental infection with Colombian isolates of G. duodenalis. Experimental Giardia infection of gerbils permit a sufficient yield of cysts and trophozoites to be used as antigens for the immunization of other animals and to obtain Giardia antibodies that could be used for Giardia antigen detection assays in stool specimens.

  18. Antifungal activity of caspofungin in experimental infective endocarditis caused by Candida albicans.

    Science.gov (United States)

    Victorio, Gerardo Becerra; Bourdon, Lorena Michele Brennan; Benavides, Leonel García; Huerta-Olvera, Selene G; Plascencia, Arturo; Villanueva, José; Martinez-Lopez, Erika; Hernández-Cañaveral, Iván Isidro

    2017-05-01

    Infective endocarditis is a disease characterised by heart valve lesions, which exhibit extracellular matrix proteins that act as a physical barrier to prevent the passage of antimicrobial agents. The genus Candida has acquired clinical importance given that it is increasingly being isolated from cases of nosocomial infections. To evaluate the activity of caspofungin compared to that of liposomal amphotericin B against Candida albicans in experimental infective endocarditis. Wistar rats underwent surgical intervention and infection with strains of C. albicans to develop infective endocarditis. Three groups were formed: the first group was treated with caspofungin, the second with liposomal amphotericin B, and the third received a placebo. In vitro sensitivity was first determined to further evaluate the effect of these treatments on a rat experimental model of endocarditis by semiquantitative culture of fibrinous vegetations and histological analysis. Our semiquantitative culture of growing vegetation showed massive C. albicans colonisation in rats without treatment, whereas rats treated with caspofungin showed significantly reduced colonisation, which was similar to the results obtained with liposomal amphotericin B. The antifungal activity of caspofungin is similar to that of liposomal amphotericin B in an experimental model of infective endocarditis caused by C. albicans.

  19. Migration strategy affects avian influenza dynamics in mallards (Anas platyrhynchos).

    Science.gov (United States)

    Takekawa, John Y.; Hill, Nichola J.; Ackerman, Joshua T.; Herring, Garth; Hobson, Keith; Cardona, Carol J.; Runstadler, Jonathan; Boyce, Walter M.

    2012-01-01

    Studies of pathogen transmission typically overlook that wildlife hosts can include both migrant and resident populations when attempting to model circulation. Through the application of stable isotopes in flight feathers, we estimated the migration strategy of mallards (Anas platyrhynchos) occurring on California wintering grounds. Our study demonstrates that mallards- a principal host of avian influenza virus (AIV) in nature, contribute differently to virus gene flow depending on migration strategy. No difference in AIV prevalence was detected between resident (9.6%), intermediate-distance (9.6%) and long-distance migrants (7.4%). Viral diversity among the three groups was also comparable, possibly owing to viral pool mixing when birds converge at wetlands during winter. However, migrants and residents contributed differently to the virus gene pool at wintering wetlands. Migrants introduced virus from northern breeding grounds (Alaska and the NW Pacific Rim) into the wintering population, facilitating gene flow at continental scales, but circulation of imported virus appeared to be limited. In contrast, resident mallards acted as AIV reservoirs facilitating year-round circulation of limited subtypes (i.e. H5N2) at lower latitudes. This study supports a model of virus exchange in temperate regions driven by the convergence of wild birds with separate geographic origins and exposure histories.

  20. Experimental reproduction of an Enterococcus cecorum infection in Pekin ducks.

    Science.gov (United States)

    Jung, Arne; Metzner, Martin; Köhler-Repp, Dagmar; Rautenschlein, Silke

    2013-12-01

    Enterococcus cecorum (EC) was thus far only known as a pathogen for broilers and broiler breeders. Recently there was evidence of EC field outbreaks in Pekin duck flocks in Germany. In this study we experimentally reproduced an EC infection in Pekin ducks. At 12 days post hatch, groups of Pekin ducks were infected orally, via the thoracic air sac or intravenously with 1.5 × 10(9) colony-forming units (CFU) of EC per bird or via the air sac with 8.5 × 10(5) or 8.5 × 10(7) CFU per bird. Ducks of the intravenously infected group showed 100% mortality after 2 days post infection. The air sac inoculated high-dose group exhibited a mortality rate of 67%. Birds that were infected with 8.5 × 10(5) and 8.5 × 10(7) CFU showed 6.7% mortality after 7 days post infection. Dead birds displayed pneumonia, airsacculitis, pericarditis and splenitis and EC was re-isolated from these organs. Surviving birds of all groups apart from the orally infected ducks demonstrated clinical signs such as huddling, reduced mobility and diarrhoea. Furthermore, they showed gross pathological lesions including airsacculitis and splenitis and lower bodyweights than the control group at necropsy on days 7, 14 and 21 post infection. The present study clearly confirms that EC is pathogenic for Pekin ducks after experimental infection via the intravenous route or the respiratory tract. EC therefore has to be considered as an emerging avian pathogen not only in broilers but also in Pekin ducks.

  1. Histopathological study of experimental and natural infections by Trypanosoma cruzi in Didelphis marsupialis

    Directory of Open Access Journals (Sweden)

    João Carlos Araujo Carreira

    1996-10-01

    Full Text Available Didelphis marsupialis, the most important sylvatic reservoir of Trypanosoma cruzi, can also maintain in their anal scent glands the multiplicative forms only described in the intestinal tract of triatomine bugs. A study of 21 experimentally and 10 naturally infected opossums with T. cruzi was undertaken in order to establish the histopathological pattern under different conditions. Our results showed that the inflammation was predominantly lymphomacrophagic and more severe in the naturally infected animals but never as intense as those described in Chagas' disease or in other animal models. The parasitism in both groups was always mild with very scarce amastigote nests in the tissues. In the experimentally infected animals, the inflammation was directly related to the presence of amastigotes nests. Four 24 days-old animals, still in embryonic stage, showed multiple amastigotes nests and moderate inflammatory reactions, but even so they survived longer and presented less severe lesions than experimentally infected adult mice. Parasites were found in smooth, cardiac and/or predominantly striated muscles, as well as in nerve cells. Differing from the experimentally infected opossums parasitism in the naturally infected animals predominated in the heart, esophagus and stomach. Parasitism of the scent glands did not affect the histopathological pattern observed in extraglandular tissues.

  2. Cardiac complication after experimental human malaria infection: a case report

    Directory of Open Access Journals (Sweden)

    Druilhe Pierre

    2009-12-01

    Full Text Available Abstract A 20 year-old healthy female volunteer participated in a clinical Phase I and IIa safety and efficacy trial with candidate malaria vaccine PfLSA-3-rec adjuvanted with aluminium hydroxide. Eleven weeks after the third and last immunization she was experimentally infected by bites of Plasmodium falciparum-infected mosquitoes. When the thick blood smear became positive, at day 11, she was treated with artemether/lumefantrine according to protocol. On day 16 post-infection i.e. two days after completion of treatment, she woke up with retrosternal chest pain. She was diagnosed as acute coronary syndrome and treated accordingly. She recovered quickly and her follow-up was uneventful. Whether the event was related to the study procedures such as the preceding vaccinations, malaria infection or antimalarial drugs remains elusive. However, the relation in time with the experimental malaria infection and apparent absence of an underlying condition makes the infection the most probable trigger. This is in striking contrast, however, with the millions of malaria cases each year and the fact that such complication has never been reported in the literature. The rare occurrence of cardiac events with any of the preceding study procedures may even support a coincidental finding. Apart from acute coronary syndrome, myocarditis can be considered as a final diagnosis, but the true nature and patho-physiological explanation of the event remain unclear.

  3. HoBi-like pestivirus experimental infection in pregnant ewes: Reproductive disorders and generation of persistently infected lambs.

    Science.gov (United States)

    Decaro, Nicola; Losurdo, Michele; Larocca, Vittorio; Lucente, Maria Stella; Mari, Viviana; Varello, Katia; Patruno, Giovanni; Camero, Michele; Sciarra, Marina; Occhiogrosso, Leonardo; Tempesta, Maria; Iulini, Barbara; Buonavoglia, Canio

    2015-08-05

    In order to evaluate sheep as experimental model to test the efficacy of HoBi-like pestivirus vaccines for cattle, 10 sheep at different stages of pregnancy (30 or 50 days) were experimentally infected with the Italian prototype isolate Italy-1/10-1. Irrespective of the stage of pregnancy, virus inoculation resulted in reproductive failures, consisting of abortion, stillbirths or birth of weak or persistently infected (PI) lambs. Aborted fetuses, stillborn and dead lambs displayed extensive histopathological changes, consisting of hemorrhages, congestion and mononuclear infiltration in major organs. Pestiviral antigens were detected by immunohistochemistry in most tissues with remarkable signals in lungs and kidneys. PI lambs were constantly viremic, shed the virus through the nasal secretions and feces and, in all cases but one, did not have detectable HoBi-like pestivirus antibodies before the assumption of colostrum. The single seropositive infected lamb showed low-titer viremia and viral shedding that ceased only several weeks after the 3-month observation period. The study proves that sheep are susceptible to the reproduction failures caused by HoBi-like pestivirus infection and can serve as a suitable model for the evaluation of the fetal protection induced by homologous experimental vaccines. Copyright © 2015 Elsevier B.V. All rights reserved.

  4. The effect of age on the pathogenesis of a highly pathogenic avian influenza (HPAI) H5N1 virus in Pekin ducks (Anas platyrhynchos) infected experimentally

    OpenAIRE

    L?ndt, Brandon Z.; N??ez, Alejandro.; Banks, Jill; Alexander, Dennis J.; Russell, Christine; Richard? L?ndt, Angela C.; Brown, Ian H.

    2009-01-01

    Background? Highly pathogenic avian influenza (HPAI) H5N1 viruses have recently displayed increased virulence for wild waterfowl. Objectives? To study the effect of host age on the shedding and tissue dissemination of a HPAI H5N1 virus in infected Pekin ducks. Methods? Pekin ducks in two age?matched groups (n?=?18), 8 and 12?weeks old (wo) were each infected with 106 EID50/0?1?ml of HPAI A/turkey/Turkey/1/05 (H5N1, clade 2?2). Each day for 5?days, birds were monitored clinically, and cloacal ...

  5. Biomimicry of multifunctional nanostructures in the neck feathers of mallard (Anas platyrhynchos L.) drakes

    Science.gov (United States)

    Khudiyev, Tural; Dogan, Tamer; Bayindir, Mehmet

    2014-04-01

    Biological systems serve as fundamental sources of inspiration for the development of artificially colored devices, and their investigation provides a great number of photonic design opportunities. While several successful biomimetic designs have been detailed in the literature, conventional fabrication techniques nonetheless remain inferior to their natural counterparts in complexity, ease of production and material economy. Here, we investigate the iridescent neck feathers of Anas platyrhynchos drakes, show that they feature an unusual arrangement of two-dimensional (2D) photonic crystals and further exhibit a superhydrophobic surface, and mimic this multifunctional structure using a nanostructure composite fabricated by a recently developed top-down iterative size reduction method, which avoids the above-mentioned fabrication challenges, provides macroscale control and enhances hydrophobicity through the surface structure. Our 2D solid core photonic crystal fibres strongly resemble drake neck plumage in structure and fully polymeric material composition, and can be produced in wide array of colors by minor alterations during the size reduction process.

  6. Trypanosoma cruzi infection in the opossum Didelphis marsupialis: absence of neonatal transmission and protection by maternal antibodies in experimental infections

    Directory of Open Access Journals (Sweden)

    Ana M. Jansen

    1994-03-01

    Full Text Available The high rate of natural Trypanosoma cruzi infection found in opossums does not always correlate with appreciable densities of local triatomid populations. One alternative method which might bypass the invertebrate vector is direct transmission from mother to offspring. This possibility was investigated in five T. cruzi infected females and their litters (24 young. The influence of maternal antibodies transferred via lactation, on the course of experimental infection, was also examined. Our results show that neonatal transmission is probably not responsible for the high rate of natural T. cruzi infection among opossums. In addition antibodies of maternal origin confer a partial protection to the young. This was demonstrated by the finding of a double prepatency period and 4,5 fold lower levels of circulating parasites, in experimentally infected pouch young from infected as compared to control uninfected mothes. On the other hand, the duration of patent parasitemia was twice as long as that observed in the control group.

  7. The effect of age on the pathogenesis of a highly pathogenic avian influenza (HPAI) H5N1 virus in Pekin ducks (Anas platyrhynchos) infected experimentally.

    Science.gov (United States)

    Löndt, Brandon Z; Núñez, Alejandro; Banks, Jill; Alexander, Dennis J; Russell, Christine; Richard-Löndt, Angela C; Brown, Ian H

    2010-01-01

    Highly pathogenic avian influenza (HPAI) H5N1 viruses have recently displayed increased virulence for wild waterfowl. To study the effect of host age on the shedding and tissue dissemination of a HPAI H5N1 virus in infected Pekin ducks. Pekin ducks in two age-matched groups (n = 18), 8 and 12 weeks old (wo) were each infected with 10(6) EID(50)/0.1 ml of HPAI A/turkey/Turkey/1/05 (H5N1, clade 2.2). Each day for 5 days, birds were monitored clinically, and cloacal and oropharyngeal swabs collected, before three birds from each group were selected randomly for post-mortem examination. Tissue samples were collected for examination by real-time RT-PCR, histopathology and immunohistochemistry (IHC). Severe clinical signs, including incoordination and torticollis were observed in the 8 wo group resulting in 100% mortality by 4 dpi. Mild clinical signs were observed in the 12 wo group with no mortality. Real-time RT-PCR and IHC results demonstrated the systemic spread of H5N1 virus in birds of both age groups. Higher levels of virus shedding were detected in oropharyngeal swabs than in cloacal swabs, with similar levels of shedding detected in both age groups. Variations in level and temporal dissemination of virus within tissues of older ducks, and the presence of the virus in brain and heart were observed, which coincided with the appearance of clinical signs preceding death in younger birds. These results are consistent with reports of natural infections of wild waterfowl and poultry possibly indicating an age-related association with dissemination and clinical outcome in ducks following infection with H5N1 HPAI virus.

  8. Experimental infection of Artibeus intermedius with a vampire bat rabies virus.

    Science.gov (United States)

    Obregón-Morales, Cirani; Aguilar-Setién, Álvaro; Perea Martínez, Leonardo; Galvez-Romero, Guillermo; Martínez-Martínez, Flor Olivia; Aréchiga-Ceballos, Nidia

    2017-06-01

    Experimental infection of Artibeus intermedius, the great fruit-eating bat, was performed with vampire bat rabies isolates. Bats (n=35) were captured in the wild and quarantined prior to experimental infection. No rabies antibodies were detected by rapid fluorescent focus inhibition test (RFFIT) prior to infection. Three doses of rabies virus (RV) and three different routes of infection were used. One out of 35 bats died without showing any clinical signs at day 14 and was positive for rabies. None of the 34 other bats showed clinical signs for rabies, but high antibody titers were detected post-inoculation, suggesting either innate immune response to the vampire bat rabies virus or possible pre-exposure to RV and inoculation leading to a booster effect. Rabies virus was detected by hemi-nested RT-PCR (hnRT-PCR) in the brain (n=3), stomach (n=1) of bats that were negative by immunofluorescence and that survived rabies infection. The bat that died on day 14 was positive by hnRT-PCR on the brain, heart and liver. These results suggest that either previous non-lethal exposure to RV or natural low susceptibility to vampire bat viruses somehow protected Artibeus intermedius from clinical rabies infection leading to a marginal lethality effect on this bats species population in the wild. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Evaluation of potassium permanganate against an experimental subacute infection of Flavobacterium columnare in channel catfish, Icatlurus punctatus

    Science.gov (United States)

    The efficacy of potassium permanganate (KMnO4) as a prophylactic and therapeutic treatment for subacute infection of Flavobacterium columnare was demonstrated in experimentally infected channel catfish, Ictalurus punctatus. Catfish experimentally infected with F. columnare to mimic a subacute infec...

  10. Experimental Salmonella typhimurium infections in rats. I

    DEFF Research Database (Denmark)

    Hougen, H P; Jensen, E T; Klausen, B

    1989-01-01

    The course of experimentally induced Salmonella typhimurium infection was studied in three groups of inbred LEW rats: homozygous +/+, athymic rnu/rnu and isogeneic thymus-grafted rnu/rnu rats. In the first experiment the animals were inoculated intraperitoneally with 10(8) bacteria and all animals...... became severely septicemic and died within a week of inoculation, irrespective of presence or absence of thymus. In the second experiment the animals were inoculated with 10(6) bacteria, and both euthymic and thymus-grafted animals responded with high titres of anti bacterial antibodies while these were...... very low in the athymic nude animals. Polyclonal antibody production was only observed in the euthymic animals and only regarding IgG. Athymic rats were not able to clear the infection, while the thymus-grafted animals reacted like euthymic rats: Very few animals housed the bacteria four weeks after...

  11. Effect of Exposure Dose on Ichthyophonus Prevalence and Infection Intensity in Experimentally Infected Rainbow Trout, Oncorhynchus mykiss.

    Science.gov (United States)

    Kocan, Richard; LaPatra, Scott

    2016-02-01

    This study describes the effect of increasing exposure dose on Ichthyophonus prevalence and infection intensity in experimentally infected rainbow trout, Oncorhynchus mykiss. Specific-pathogen free trout were exposed per os to increasing numbers of Ichthyophonus schizonts obtained from naturally infected donor fish, then sampled after 30 and 60 days post-exposure. Both in vitro explant culture and histology revealed that as the number of schizonts per dose increased there was a proportionate increase in the number of infected fish, as well as an increase in the number of infected organs; parasite density in individual infected organs also increased with dose. Explant culture revealed that all fish exposed to the highest dose (≥2,080 schizonts) became infected, while only 67% of those exposed to the intermediate dose (1,040-1,153 schizonts) were Ichthyophonus-positive after 60 days; Ichthyophonus was not detected in fish exposed to the 2 lowest doses (≤280 schizonts). Histologic examination of individual infected organs also revealed increasing infection prevalence and parasite density in response to exposure to increasing numbers of Ichthyophonus schizonts.

  12. Evaluation of a simple Theileria annulata culture protocol from experimentally infected bovine whole blood

    Directory of Open Access Journals (Sweden)

    Gharbi M.

    2012-08-01

    Full Text Available We have evaluated a new simple technique using whole blood from experimentally infected cattle for the isolation and cultivation of Theileria annulata. The study was carried out on 20 Holstein-Frisian bovines that had been experimentally infected with a virulent lethal dose of Theileria annulata. This technique has been compared to the classical peripheral blood monocyte isolation with Ficoll carried out on 22 experimentally infected Holstein-Friesian calves. The effectiveness of the reference technique was estimated to 86.4%, whilst the effectiveness of the new technique was 100%. Moreover, this new technique leads to time and money saving estimated to € 3.06 per sample. It decreases the contamination risks by reducing the steps of sample manipulation.

  13. Suppression of inflammatory immune responses in celiac disease by experimental hookworm infection.

    Directory of Open Access Journals (Sweden)

    Henry J McSorley

    Full Text Available We present immunological data from two clinical trials where the effect of experimental human hookworm (Necator americanus infection on the pathology of celiac disease was evaluated. We found that basal production of Interferon- (IFN-γ and Interleukin- (IL-17A from duodenal biopsy culture was suppressed in hookworm-infected participants compared to uninfected controls. Increased levels of CD4+CD25+Foxp3+ cells in the circulation and mucosa are associated with active celiac disease. We show that this accumulation also occurs during a short-term (1 week oral gluten challenge, and that hookworm infection suppressed the increase of circulating CD4+CD25+Foxp3+ cells during this challenge period. When duodenal biopsies from hookworm-infected participants were restimulated with the immunodominant gliadin peptide QE65, robust production of IL-2, IFN-γ and IL-17A was detected, even prior to gluten challenge while participants were strictly adhering to a gluten-free diet. Intriguingly, IL-5 was produced only after hookworm infection in response to QE65. Thus we hypothesise that hookworm-induced TH2 and IL-10 cross-regulation of the TH1/TH17 inflammatory response may be responsible for the suppression of these responses during experimental hookworm infection.

  14. Serum levels of cytokines in water buffaloes experimentally infected with Fasciola gigantica.

    Science.gov (United States)

    Zhang, Fu-Kai; Guo, Ai-Jiang; Hou, Jun-Ling; Sun, Miao-Miao; Sheng, Zhao-An; Zhang, Xiao-Xuan; Huang, Wei-Yi; Elsheikha, Hany M; Zhu, Xing-Quan

    2017-09-15

    Fasciola gigantica infection in water buffaloes causes significant economic losses especially in developing countries. Although modulation of the host immune response by cytokine neutralization or vaccination is a promising approach to control infection with this parasite, our understanding of cytokine's dynamic during F. gigantica infection is limited. To address this, we quantified the levels of serum cytokines produced in water buffaloes following experimental infection with F. gigantica. Five buffaloes were infected via oral gavage with 500 viable F. gigantica metacercariae and blood samples were collected from buffaloes one week before infection and for 13 consecutive weeks thereafter. The levels of 10 cytokines in serum samples were simultaneously determined using ELISA. F. gigantica failed to elicit the production of various pro-inflammatory cytokines, including interleukin-1β (IL-1β), IL-2, IL-6, IL-12, and IFN-γ. On the other hand, evidence of a Th2 type response was detected, but only early in the course of parasite colonization and included modest increase in the levels of IL-10 and IL-13. The results also revealed suppression of the immune responses as a feature of chronic F. gigantica infection in buffaloes. Taken together, F. gigantica seems to elicit a modest Th2 response at early stage of infection in order to downregulate harmful Th1- and Th17-type inflammatory responses in experimentally infected buffaloes. The full extent of anti-F. gigantica immune response and its relation to pathogenesis requires further study. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Imaging experimental infective endocarditis with indium-111-labeled blood cellular components

    International Nuclear Information System (INIS)

    Riba, A.L.; Thakur, M.L.; Gottschalk, A.; Andriole, V.T.; Zaret, B.L.

    1979-01-01

    The capability of radionuclide imaging to detect experimental aortic valve infective endocarditis was assessed with indium-111 ( 111 In)-labeled blood cells. Sequential cardiac imaging and tissue distribution studies were obtained in 17 rabbits with infective endocarditis after administration of 111 In-platelets and in five after 111 In-polymorphonuclear leukocytes. Forty-eight to 72 hours after platelet administration, in vivo imaging demonstrated abnormal 111 In uptake in all animals in the region of the aortic valve in an anatomically distinct pattern. Images of the excised heart showed discrete cardiac uptake conforming to the in vivo image and gross pathological examination. 111 In-platelet uptake in vegetations from the 17 animals averaged 240 +- 41 times greater than that in normal myocardium and 99 +- 15 times greater uptake in blood. In contrast, 111 In-leukocyte cardiac imaging showed no abnormal aortic valve uptake 24 hours after tracer administration and the lesion myocardium activity ratio was only 5 +- 2 (3 +- 1 for lesion/blood activity). Four normal rabbits demonstrated neither positive 111 In-platelet scintigraphs nor abnormal cardiac tissue uptake. Likewise, noncellular 111 In was not concentrated to any significant extent in three animals with infective endocarditis. This study demonstrates that 111 In-platelet, but not leukocyte cardiac imaging, is a sensitive technique for detecting experimental infective endocarditis. The imaging data conform to the cellular pathology of the infective endocarditis vegetation

  16. The pathogenesis of single experimental infections with Strongylus vulgaris in foals.

    Science.gov (United States)

    Duncan, J L; Pirie, H M

    1975-01-01

    The clinical signs, pathology and clinical pathology associated with single experimental infections of Strongylus vulgaris in worm-free pony foals are described. The major clinical signs which became apparent in the infected foals during the first three weeks were pyrexia, anorexia, dullness and abdominal pain. Within the first two weeks of infection lesions were confined to the intestine and terminal branches of the intestinal arteries and consisted of mucosal, submucosal and serosal haemorrhage together with arteritis of submucosal and serosal arteries and also a marked inflammatory reaction. The main lesion seen three weeks after infection was gross thrombosis of the anterior mesenteric artery or one of its major branches. On section these affected arteries showed marked intimal thickening with infiltration of plasma cells, lymphocytes, macrophages and neutrophils. Between one and four months after infection the gross lesions were predominantly in the arteries and consisted of fibrous thickening of the arterial wall and thrombosis associated with the presence of developing fourth stage larvae. Four months after infection the arterial lesions were still prominent and microscopically there was fibrosis of the wall of the affected artery with wide-spread disruption of the intima. In the adventitia organised thrombi were apparent in the vasa vasorum and resulted in the obliteration of their lumina. The typical lesion associated with the return of fifth stage larvae to the intestine was nodule formation in close proximity to thrombosed terminal intestinal arteries and sections of parasites were seen in the intestinal wall surrounded by neutrophils and necrotic debris. By nine months after infection the arterial lesion had healed, but histologically there was fibrosis of the intima and macrophages containing haemosiderin were seen in the arterial wall. The most significant haematological findings during the experimental period were a marked polymorphonuclear

  17. Efficacy of imidocarb dipropionate in eliminating Theileria equi from experimentally infected horses.

    Science.gov (United States)

    Grause, Juanita F; Ueti, Massaro W; Nelson, Jeffrey T; Knowles, Donald P; Kappmeyer, Lowell S; Bunn, Thomas O

    2013-06-01

    Theileria equi, one of the causative agents of equine piroplasmosis, is endemic in many regions of the world but is considered a 'foreign' animal disease in the USA. In an effort to prevent the importation of T. equi, stringent serological screening of horses is practiced prior to entry to the USA. Current regulatory options available where horses are found to be infected include permanent quarantine with or without chemotherapy, repatriation, or euthanasia. Chemotherapeutics that eliminate infection and subsequently transmission risk are critical in the management of infected horses. In this study, the efficacy of the drug imidocarb dipropionate against experimental T. equi infection was assessed. Of nine horses experimentally inoculated with T. equi isolated from an animal previously imported from Peru, six were treated with imidocarb dipropionate after the resolution of the acute phase of the disease. Elimination of the parasite was demonstrated in 5/6 by nested PCR, blood transfusions to naïve horses, and reversion to seronegative status. The findings support the use of this drug as a potential treatment option in controlling outbreaks of T. equi, and also suggest that 'combination testing' using both serological and PCR detection methods are necessary to demonstrate clearance of infection. Published by Elsevier Ltd.

  18. Therapeutic effect of cefozopran (SCE-2787), a new parenteral cephalosporin, against experimental infections in mice.

    Science.gov (United States)

    Iizawa, Y; Okonogi, K; Hayashi, R; Iwahi, T; Yamazaki, T; Imada, A

    1993-01-01

    The therapeutic effect of cefozopran (SCE-2787), a new semisynthetic parenteral cephalosporin, against experimental infections in mice was examined. Cefozopran was more effective than cefpiramide and was as effective as ceftazidime and cefpirome against acute respiratory tract infections caused by Klebsiella pneumoniae DT-S. In the model of chronic respiratory tract infection caused by K. pneumoniae 27, cefozopran was as effective as ceftazidime. The therapeutic effect of cefozopran against urinary tract infections caused by Pseudomonas aeruginosa P9 was superior to that of cefpirome and was equal to those of ceftazidime and cefclidin. In addition, cefozopran was more effective than ceftazidime and was as effective as flomoxef in a thigh muscle infection caused by methicillin-sensitive Staphylococcus aureus 308A-1. Against thigh muscle infections caused by methicillin-resistant S. aureus N133, cefozopran was the most effective agent. The potent therapeutic effect of cefozopran in those experimental infections in mice suggests that it would be effective against respiratory tract, urinary tract, and soft tissue infections caused by a variety of gram-positive and gram-negative bacteria in humans. PMID:8431004

  19. Embryotoxic and teratogenic effects of petroleum hydrocarbons in mallards (Anas platyrhynchos)

    Science.gov (United States)

    Hoffman, D.J.

    1979-01-01

    Egg surface applications of microliter quantities of crude and refined oils of high aromatic content are embryotoxic to mallards (Anas platyrhynchos) and other avian species; applications of aliphatic hydrocarbons have virtually no effect. Mallard eggs at 72 h of development were exposed to a mixture of aromatic hydrocarbons or to aromatic compounds representative to those present in crude oil to assess their toxicity. The class composition of the mixture was similar to that of South Louisiana crude oil, an American Petroleum Institute reference oil. Application of 20 microliter of the mixture reduced embryonic survival by nearly 70%. The temporal pattern of embryonic death was similar to that after exposure to South Louisiana crude oil. Embryonic growth was stunted, as reflected by weight, crown-rump length, and bill length, and there was a significant increase in the incidence of abnormal survivors. When individual classes of aromatic hydrocarbons were tested, tetracyclics caused some embryonic death at the concentrations in the mixture. When classes were tested in all possible combinations of two, no combination appeared to be as toxic as the entire mixture. Addition of the tetracyclic compound chrysene to the aromatic mixture considerably enhanced embryotoxicity, but could not completely account for the toxicity of the crude oil. The presence of additional unidentified polycyclic aromatic hydrocarbons as well as methylated derivatives of polycyclic aromatic compounds such as chrysene may further account for the embryotoxicity of the crude oil.

  20. Immunologic responses in corn snakes (Pantherophis guttatus) after experimentally induced infection with ferlaviruses.

    Science.gov (United States)

    Neul, Annkatrin; Schrödl, Wieland; Marschang, Rachel E; Bjick, Tina; Truyen, Uwe; von Buttlar, Heiner; Pees, Michael

    2017-04-01

    OBJECTIVE To measure immunologic responses of snakes after experimentally induced infection with ferlaviruses. ANIMALS 42 adult corn snakes (Pantherophis guttatus) of both sexes. PROCEDURES Snakes were inoculated intratracheally with genogroup A (n = 12), B (12), or C (12) ferlavirus (infected groups) or cell-culture supernatant (6; control group) on day 0. Three snakes from each infected group were euthanized on days 4, 16, 28, and 49, and 3 snakes from the control group were euthanized on day 49. Blood samples were collected from live snakes on days -6 (baseline), 4, 16, 28, and 49. Hematologic tests were performed and humoral responses assessed via hemagglutination-inhibition assays and ELISAs. Following euthanasia, gross pathological and histologic evaluations and virus detection were performed. RESULTS Severity of clinical signs of and immunologic responses to ferlavirus infection differed among snake groups. Hematologic values, particularly WBC and monocyte counts, increased between days 4 and 16 after infection. A humoral response was identified between days 16 and 28. Serum IgM concentrations increased from baseline earlier than IgY concentrations, but the IgY relative increase was higher at the end of the study. The hemagglutination-inhibition assay revealed that the strongest reactions in all infected groups were against the strain with which they had been infected. Snakes infected with genogroup A ferlavirus had the strongest immune response, whereas those infected with genogroup B had the weakest responses. CONCLUSIONS AND CLINICAL RELEVANCE Results of this experimental study suggested that the ferlavirus strain with the highest virulence induced the weakest immune response in snakes.

  1. Characterising the mucosal and systemic immune responses to experimental human hookworm infection.

    Directory of Open Access Journals (Sweden)

    Soraya Gaze

    2012-02-01

    Full Text Available The mucosal cytokine response of healthy humans to parasitic helminths has never been reported. We investigated the systemic and mucosal cytokine responses to hookworm infection in experimentally infected, previously hookworm naive individuals from non-endemic areas. We collected both peripheral blood and duodenal biopsies to assess the systemic immune response, as well as the response at the site of adult worm establishment. Our results show that experimental hookworm infection leads to a strong systemic and mucosal Th2 (IL-4, IL-5, IL-9 and IL-13 and regulatory (IL-10 and TGF-β response, with some evidence of a Th1 (IFN-γ and IL-2 response. Despite upregulation after patency of both IL-15 and ALDH1A2, a known Th17-inducing combination in inflammatory diseases, we saw no evidence of a Th17 (IL-17 response. Moreover, we observed strong suppression of mucosal IL-23 and upregulation of IL-22 during established hookworm infection, suggesting a potential mechanism by which Th17 responses are suppressed, and highlighting the potential that hookworms and their secreted proteins offer as therapeutics for human inflammatory diseases.

  2. Detection of Toxoplasma gondii DNA in sera samples of mice experimentally infected

    Directory of Open Access Journals (Sweden)

    H. Langoni

    2006-04-01

    Full Text Available Detection of Toxoplasma gondii (T. gondii DNA in blood can help to diagnose the disease in its acute phase; however, it must be considered that hemoglobin, present in blood, can inhibit polymerase activity, making impracticable the detection of DNA in samples. Mice were experimentally infected via oral route with ME49 and BTU2 strains cysts and RH strain tachyzoites; polymerase chain reaction was used to detect T. gondii DNA in mice sera 18, 24, 48, 96, and 192 hours post infection (PI. Toxoplama gondii DNA was detected in only one animal infected with BTU2 strain, genotype III (isolated from a dog with neurological signs 18 hours PI. The agent's DNA was not detected in any sample of the other experimental groups. New studies must be carried out to verify the technique sensitivity in researches on this agent's genetic material using sera samples of acute-phase toxoplasmosis patients, especially in cases of immunosuppression.

  3. E-ADA activity in serum of lambs experimentally infected with Haemonchus contortus.

    Science.gov (United States)

    Da Silva, Aleksandro S; Fausto, Guilherme C; Grando, Thirssa H; Cadore, Carlos A; Pimentel, Victor C; Jaques, Jeandre A; Schetinger, Maria R C; Monteiro, Silvia G; Leal, Marta L R

    2013-08-01

    The aim of this study was to evaluate adenosine deaminase (E-ADA) activity in sera of lambs experimentally infected with Haemonchus contortus. We used 12 lambs divided into 2 groups; Group A had 5 healthy, non-infected animals (control) and Group B had 7 healthy animals infected with H. contortus . Lambs were infected orally with 500 larvae (L3) per animal every 2 days, for a period of 20 days, and later the infection was confirmed by examination of feces (eggs per gram [EPG] via fecal egg count). Blood collection was performed at days 0, 20, 40, 60, and 80 post-infection (PI) for analysis of E-ADA activity. Animals in Group A showed negative EPG throughout the experiment unlike those from Group B that had elevated EPG counts. E-ADA activity was reduced in the serum of animals infected with H. contortus when compared to non-infected controls at days 20, 40, 60, and 80 PI. Therefore, it is concluded that infection with H. contortus influences the E-ADA activity in lambs.

  4. Experimental cross-species infection of common marmosets by titi monkey adenovirus.

    Directory of Open Access Journals (Sweden)

    Guixia Yu

    Full Text Available Adenoviruses are DNA viruses that infect a number of vertebrate hosts and are associated with both sporadic and epidemic disease in humans. We previously identified a novel adenovirus, titi monkey adenovirus (TMAdV, as the cause of a fulminant pneumonia outbreak in a colony of titi monkeys (Callicebus cupreus at a national primate center in 2009. Serological evidence of infection by TMAdV was also found in a human researcher at the facility and household family member, raising concerns for potential cross-species transmission of the virus. Here we present experimental evidence of cross-species TMAdV infection in common marmosets (Callithrix jacchus. Nasal inoculation of a cell cultured-adapted TMAdV strain into three marmosets produced an acute, mild respiratory illness characterized by low-grade fever, reduced activity, anorexia, and sneezing. An increase in virus-specific neutralization antibody titers accompanied the development of clinical signs. Although serially collected nasal swabs were positive for TMAdV for at least 8 days, all 3 infected marmosets spontaneously recovered by day 12 post-inoculation, and persistence of the virus in tissues could not be established. Thus, the pathogenesis of experimental inoculation of TMAdV in common marmosets resembled the mild, self-limiting respiratory infection typically seen in immunocompetent human hosts rather than the rapidly progressive, fatal pneumonia observed in 19 of 23 titi monkeys during the prior 2009 outbreak. These findings further establish the potential for adenovirus cross-species transmission and provide the basis for development of a monkey model useful for assessing the zoonotic potential of adenoviruses.

  5. Transcriptomic study of 39 ostreid herpesvirus 1 genes during an experimental infection.

    Science.gov (United States)

    Segarra, Amélie; Faury, Nicole; Pépin, Jean-François; Renault, Tristan

    2014-06-01

    Massive mortality outbreaks have been reported in France since 2008 among Pacific oysters, Crassostrea gigas, with the detection of a particular OsHV-1 variant called μVar. Virus infection can be induced in healthy spat in experimental conditions allowing to better understand the disease process, including viral gene expression. Although gene expression of other herpesviruses has been widely studied, we provide the first study following viral gene expression of OsHV-1 over time. In this context, an in vivo transcriptomic study targeting 39 OsHV-1 genes was carried out during an experimental infection of Pacific oyster spat. For the first time, several OsHV-1 mRNAs were detected by real-time PCR at 0 h, 2 h, 4 h, 18 h, 26 h and 42 h post-injection. Several transcripts were detected at 2h post-infection and at 18 h post-infection for all selected ORFs. Quantification of virus gene expression at different times of infection was also carried out using an oyster housekeeping gene, Elongation factor. Developing an OsHV-1-specific reverse transcriptase real time PCR targeting 39 viral gene appears a new tool in terms of diagnosis and can be used to complement viral DNA detection in order to monitor viral replication. Copyright © 2014. Published by Elsevier Inc.

  6. Excretion of [3H]prednisolone in clinically normal and experimentally infected bovine udders

    International Nuclear Information System (INIS)

    Geleta, J.N.; Shimoda, W.; Mercer, H.D.

    1984-01-01

    The excretion rate of [3H]prednisolone from clinically normal and experimentally infected udders of 10 lactating cows was studied. Each quarter of 6 cows was injected with a single dose of [3H]prednisolone mixed with non-radioactive prednisolone equivalent to 10 mg in 10 ml of peanut oil base. Each of the remaining 4 cows was given 40 mg of nonradioactive prednisolone and [3H]prednisolone in 60% ethanol IV. Control and postadministration samples of blood, milk, and urine were examined for radioactivity. The effects of [3H]prednisolone were evaluated in the same cows, first in clinically normal udders, then 2 weeks later in udders experimentally infected with Streptococcus agalactiae. Absorption and elimination of prednisolone were the same before and after induced infection. Within 3 hours after intramammary injection, 95% of the labeled prednisolone was absorbed systemically, less than 5% of this dose was recovered in milk, and 29% was excreted in urine. After IV injection of [3H]prednisolone, less than 0.2% of the total radioactivity was recovered in milk and less than 46% was excreted in urine. Clinical mastitis induced by S agalactiae was moderate. Circulating blood leukocytes and somatic cells in the milk of normal cows remained essentially unchanged. The leukocyte response to induced infection was rapid in blood and milk. Large numbers of leukocytes were noticed in the milk and a severe leukopenia occurred. Prednisolone treatment did not alter the number of somatic cells in milk or reduce the inflammatory response of experimentally infected cows

  7. Excretion of (3H)prednisolone in clinically normal and experimentally infected bovine udders

    Energy Technology Data Exchange (ETDEWEB)

    Geleta, J.N.; Shimoda, W.; Mercer, H.D.

    1984-08-01

    The excretion rate of (3H)prednisolone from clinically normal and experimentally infected udders of 10 lactating cows was studied. Each quarter of 6 cows was injected with a single dose of (3H)prednisolone mixed with non-radioactive prednisolone equivalent to 10 mg in 10 ml of peanut oil base. Each of the remaining 4 cows was given 40 mg of nonradioactive prednisolone and (3H)prednisolone in 60% ethanol IV. Control and postadministration samples of blood, milk, and urine were examined for radioactivity. The effects of (3H)prednisolone were evaluated in the same cows, first in clinically normal udders, then 2 weeks later in udders experimentally infected with Streptococcus agalactiae. Absorption and elimination of prednisolone were the same before and after induced infection. Within 3 hours after intramammary injection, 95% of the labeled prednisolone was absorbed systemically, less than 5% of this dose was recovered in milk, and 29% was excreted in urine. After IV injection of (3H)prednisolone, less than 0.2% of the total radioactivity was recovered in milk and less than 46% was excreted in urine. Clinical mastitis induced by S agalactiae was moderate. Circulating blood leukocytes and somatic cells in the milk of normal cows remained essentially unchanged. The leukocyte response to induced infection was rapid in blood and milk. Large numbers of leukocytes were noticed in the milk and a severe leukopenia occurred. Prednisolone treatment did not alter the number of somatic cells in milk or reduce the inflammatory response of experimentally infected cows.

  8. Genetic variability of Taenia solium cysticerci recovered from experimentally infected pigs and from naturally infected pigs using microsatellite markers.

    Science.gov (United States)

    Pajuelo, Mónica J; Eguiluz, María; Roncal, Elisa; Quiñones-García, Stefany; Clipman, Steven J; Calcina, Juan; Gavidia, Cesar M; Sheen, Patricia; Garcia, Hector H; Gilman, Robert H; Gonzalez, Armando E; Zimic, Mirko

    2017-12-01

    The adult Taenia solium, the pork tapeworm, usually lives as a single worm in the small intestine of humans, its only known definitive host. Mechanisms of genetic variation in T. solium are poorly understood. Using three microsatellite markers previously reported [1], this study explored the genetic variability of T. solium from cysts recovered from experimentally infected pigs. It then explored the genetic epidemiology and transmission in naturally infected pigs and adult tapeworms recovered from human carriers from an endemic rural community in Peru. In an initial study on experimental infection, two groups of three piglets were each infected with proglottids from one of two genetically different tapeworms for each of the microsatellites. After 7 weeks, pigs were slaughtered and necropsy performed. Thirty-six (92.3%) out of 39 cysts originated from one tapeworm, and 27 (100%) out of 27 cysts from the other had exactly the same genotype as the parental tapeworm. This suggests that the microsatellite markers may be a useful tool for studying the transmission of T. solium. In the second study, we analyzed the genetic variation of T. solium in cysts recovered from eight naturally infected pigs, and from adult tapeworms recovered from four human carriers; they showed genetic variability. Four pigs had cysts with only one genotype, and four pigs had cysts with two different genotypes, suggesting that multiple infections of genetically distinct parental tapeworms are possible. Six pigs harbored cysts with a genotype corresponding to one of the identified tapeworms from the human carriers. In the dendrogram, cysts appeared to cluster within the corresponding pigs as well as with the geographical origin, but this association was not statistically significant. We conclude that genotyping of microsatellite size polymorphisms is a potentially important tool to trace the spread of infection and pinpoint sources of infection as pigs spread cysts with a shared parental genotype.

  9. Genetic variability of Taenia solium cysticerci recovered from experimentally infected pigs and from naturally infected pigs using microsatellite markers.

    Directory of Open Access Journals (Sweden)

    Mónica J Pajuelo

    2017-12-01

    Full Text Available The adult Taenia solium, the pork tapeworm, usually lives as a single worm in the small intestine of humans, its only known definitive host. Mechanisms of genetic variation in T. solium are poorly understood. Using three microsatellite markers previously reported [1], this study explored the genetic variability of T. solium from cysts recovered from experimentally infected pigs. It then explored the genetic epidemiology and transmission in naturally infected pigs and adult tapeworms recovered from human carriers from an endemic rural community in Peru. In an initial study on experimental infection, two groups of three piglets were each infected with proglottids from one of two genetically different tapeworms for each of the microsatellites. After 7 weeks, pigs were slaughtered and necropsy performed. Thirty-six (92.3% out of 39 cysts originated from one tapeworm, and 27 (100% out of 27 cysts from the other had exactly the same genotype as the parental tapeworm. This suggests that the microsatellite markers may be a useful tool for studying the transmission of T. solium. In the second study, we analyzed the genetic variation of T. solium in cysts recovered from eight naturally infected pigs, and from adult tapeworms recovered from four human carriers; they showed genetic variability. Four pigs had cysts with only one genotype, and four pigs had cysts with two different genotypes, suggesting that multiple infections of genetically distinct parental tapeworms are possible. Six pigs harbored cysts with a genotype corresponding to one of the identified tapeworms from the human carriers. In the dendrogram, cysts appeared to cluster within the corresponding pigs as well as with the geographical origin, but this association was not statistically significant. We conclude that genotyping of microsatellite size polymorphisms is a potentially important tool to trace the spread of infection and pinpoint sources of infection as pigs spread cysts with a shared

  10. PCR diagnostics underestimate the prevalence of avian malaria (Plasmodium relictum) in experimentally-infected passerines

    Science.gov (United States)

    Jarvi, Susan I.; Schultz, Jeffrey J.; Atkinson, Carter T.

    2002-01-01

    Several polymerase chain reaction (PCR)-based methods have recently been developed for diagnosing malarial infections in both birds and reptiles, but a critical evaluation of their sensitivity in experimentally-infected hosts has not been done. This study compares the sensitivity of several PCR-based methods for diagnosing avian malaria (Plasmodium relictum) in captive Hawaiian honeycreepers using microscopy and a recently developed immunoblotting technique. Sequential blood samples were collected over periods of up to 4.4 yr after experimental infection and rechallenge to determine both the duration and detectability of chronic infections. Two new nested PCR approaches for detecting circulating parasites based on P. relictum 18S rRNA genes and the thrombospondin-related anonymous protein (TRAP) gene are described. The blood smear and the PCR tests were less sensitive than serological methods for detecting chronic malarial infections. Individually, none of the diagnostic methods was 100% accurate in detecting subpatent infections, although serological methods were significantly more sensitive (97%) than either nested PCR (61–84%) or microscopy (27%). Circulating parasites in chronically infected birds either disappear completely from circulation or to drop to intensities below detectability by nested PCR. Thus, the use of PCR as a sole means of detection of circulating parasites may significantly underestimate true prevalence.

  11. Pathogenesis of Highly Pathogenic Avian Influenza (HPAI) A/turkey/Turkey/1/2005 H5N1 in Pekin ducks (Anas platyrhynchos) infected experimentally

    OpenAIRE

    Löndt , Brandon Z.; Nunez , Alejandro; Banks , Jill; Nili , Hassan; Johnson , Linda K; Alexander , Dennis

    2008-01-01

    Abstract Asian H5N1 (hereafter referred to as panzootic H5N1) highly pathogenic avian influenza (HPAI) virus has caused large numbers of deaths in both poultry and wild bird populations. Recent isolates of this virus have been reported to cause disease and death in commercial ducks, which has not been seen with other HPAI viruses. However, little is known about the dissemination of this H5N1 within the organs and the cause of death in infected ducks. Nineteen 4-week-old Pekin ducks...

  12. Hematologic profile of hematophagous Desmodus rotundus bats before and after experimental infection with rabies virus

    Directory of Open Access Journals (Sweden)

    Marilene Fernandes de Almeida

    2014-06-01

    Full Text Available Introduction Hematophagous Desmodus rotundus bats play an important role in the rabies lifecycle. This study describes the hematological profile of these bats before and after experimental infection with rabies virus. Methods Cells counts were performed in a Neubauer chamber. Results The average values of erythrocytes and leucocytes counts in blood before experimental infections were 9.97 × 106mm3 and 4.80 × 103mm3, respectively. Neutrophils represented 69.9% of white blood cells and the lymphocytes represented 26.9%. Following the experimental infections, the average numbers of erythrocytes and leucocytes was 9.43 × 106mm3 and 3.98 × 103mm3, respectively. Neutrophils represented 40% of white blood cells and the lymphocytes represented 59%. Conclusions The hematological profile given in this study can serve as reference values for D. rotundus bats.

  13. Efficacy of albendazole against Taenia multiceps larvae in experimentally infected goats.

    Science.gov (United States)

    Afonso, Sónia M S; Neves, Luis; Pondja, Alberto; Macuamule, Cristiano; Mukaratirwa, Samson; Arboix, Margarita; Cristòfol, Carles; Capece, Bettencourt P S

    2014-12-15

    A controlled trial was conducted to evaluate the efficacy of three therapeutics regimes of albendazole (ABZ) against Taenia multiceps larvae in experimental infected goats. Forty-nine goats experimentally infected with 3000 T. multiceps eggs were selected and randomly divided into treatment or control groups. Treatment with 10mg/kg for 3 days for group 1 (G1), 10mg/kg for group 2 (G2) and 20mg/kg/day for group 3 (G3) was applied 2 months after infection; group 4 (G4) served as a control group. A treatment with doses of 10mg/kg/day for 3 days on group 5 (G5) and group 6 (G6) was used as control, 5 months after the infection. The efficacy of ABZ was assessed as percentage of non-viable cysts which were determined by morphologic characteristics, movement and methyl blue staining technique. The efficacy of ABZ against 2 months old cysts was significantly different from the control and were 90.3% (28/31), 72.7% (8/11) and 73.9% (14/19) for G1, G2 and G3, respectively. No differences were observed in cyst viability between treated and control groups for 5-month old cysts. The results in this study indicate that ABZ is effective in goats against 2-month-old cysts of T. multiceps larva located in tissues outside the brain. Copyright © 2014 Elsevier B.V. All rights reserved.

  14. Experimental Infection and Clearance of Coccidian Parasites in Mercury-Exposed Zebra Finches.

    Science.gov (United States)

    Ebers Smith, Jessica H; Cristol, Daniel A; Swaddle, John P

    2018-01-01

    Mercury is a globally distributed, persistent environmental contaminant that affects the health of many taxa. It can suppress the immune system, which often plays a role in defense against parasites. However, there have been few investigations of whether mercury affects the abilities of animals to resist parasitic infection. Here, we exposed zebra finches to a lifetime dietary exposure of methylmercury (1.2 μg/g wet weight) and experimentally infected them with coccidian parasites to examine the effect of methylmercury exposure on parasitic infection. The mercury-exposed birds did not have an altered immune response (heterophil:lymphocyte ratio) nor a reduced ability to clear the infection. However, mercury-exposed birds tended to have higher parasite loads at the time when we expected the greatest immune response (2-3 weeks post-infection). Although mercury did not greatly influence the infection-course of this parasite in captivity, responses may be more accentuated in the wild where birds face additional immune challenges.

  15. Molecular diagnosis of Eimeria stiedae in hepatic tissue of experimentally infected rabbits.

    Science.gov (United States)

    Hassan, Khaled M; Arafa, Waleed M; Mousa, Waheed M; Shokier, Khaled A M; Shany, Salama A; Aboelhadid, Shawky M

    2016-10-01

    The early detection of Eimeria stiedae in the hepatic tissue of experimentally infected rabbits was investigated using molecular assay. Forty 6-week-old male New Zealand rabbits were divided into two groups. Group A (30 animals) was infected with 2.5 × 10(4) sporulated oocysts of E. stiedae per animal on Day 0 and Group B (10 animals) was used as the uninfected controls. Three animals from Group A and one from Group B were sacrificed at 0, 3, 6, 9, 12, 15, 18, 21, 24 and 27 days post infection (PI). Gross and microscopic post-mortem findings were recorded. Polymerase chain reaction (PCR) of the E. stiedae internal transcribed spacer 1 genomic region was conducted on blood, liver tissue, and feces from the Group A experimentally infected animals. Macroscopically, the liver showed irregular yellowish white nodules pathognomonic to E. stiedae infection beginning on Day 15 PI. Hepatomegaly and ascites were obvious from Day 21-24 PI. The presence of different E. stiedae schizonts and gametocytes in the histopathological sections of the biliary epithelium were evident on Day 15 PI. The E. stiedae PCR was first positive in liver tissues on Day 12 and in fecal samples on Day 18 PI, but the blood samples were negative. In conclusion, the PCR can be used for early diagnosis and control of E. stiedae schizonts before shedding of the oocysts in feces. Copyright © 2016 Elsevier Inc. All rights reserved.

  16. Heterogeneous infectiousness in guinea pigs experimentally infected with Trypanosoma cruzi.

    Science.gov (United States)

    Castillo-Neyra, Ricardo; Borrini Mayorí, Katty; Salazar Sánchez, Renzo; Ancca Suarez, Jenny; Xie, Sherrie; Náquira Velarde, Cesar; Levy, Michael Z

    2016-02-01

    Guinea pigs are important reservoirs of Trypanosoma cruzi, the causative parasite of Chagas disease, and in the Southern Cone of South America, transmission is mediated mainly by the vector Triatoma infestans. Interestingly, colonies of Triatoma infestans captured from guinea pig corrals sporadically have infection prevalence rates above 80%. Such high values are not consistent with the relatively short 7-8 week parasitemic period that has been reported for guinea pigs in the literature. We experimentally measured the infectious periods of a group of T. cruzi-infected guinea pigs by performing xenodiagnosis and direct microscopy each week for one year. Another group of infected guinea pigs received only direct microscopy to control for the effect that inoculation by triatomine saliva may have on parasitemia in the host. We observed infectious periods longer than those previously reported in a number of guinea pigs from both the xenodiagnosis and control groups. While some guinea pigs were infectious for a short time, other "super-shedders" were parasitemic up to 22 weeks after infection, and/or positive by xenodiagnosis for a year after infection. This heterogeneity in infectiousness has strong implications for T. cruzi transmission dynamics and control, as super-shedder guinea pigs may play a disproportionate role in pathogen spread. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  17. An experimental model of mycobacterial infection under corneal flaps

    Directory of Open Access Journals (Sweden)

    C.B.D. Adan

    2004-07-01

    Full Text Available In order to develop a new experimental animal model of infection with Mycobacterium chelonae in keratomileusis, we conducted a double-blind prospective study on 24 adult male New Zealand rabbits. One eye of each rabbit was submitted to automatic lamellar keratotomy with the automatic corneal shaper under general anesthesia. Eyes were immunosuppressed by a single local injection of methyl prednisolone. Twelve animals were inoculated into the keratomileusis interface with 1 µl of 10(6 heat-inactivated bacteria (heat-inactivated inoculum controls and 12 with 1 µl of 10(6 live bacteria. Trimethoprim drops (0.1%, w/v were used as prophylaxis for the surgical procedure every 4 h (50 µl, qid. Animals were examined by 2 observers under a slit lamp on the 1st, 3rd, 5th, 7th, 11th, 16th, and 23rd postoperative days. Slit lamp photographs were taken to document clinical signs. Animals were sacrificed when corneal disease was detected and corneal samples were taken for microbiological analysis. Eleven of 12 experimental rabbits developed corneal disease, and M. chelonae could be isolated from nine rabbits. Eleven of the 12 controls receiving a heat-inactivated inoculum did not develop corneal disease. M. chelonae was not isolated from any of the control rabbits receiving a heat-inactivated inoculum, or from the healthy cornea of control rabbits. Corneal infection by M. chelonae was successfully induced in rabbits submitted to keratomileusis. To our knowledge, this is the first animal model of M. chelonae infection following corneal flaps for refractive surgery to be described in the literature and can be used for the analysis of therapeutic responses.

  18. Metabolomic profiling in cattle experimentally infected with Mycobacterium avium subsp. paratuberculosis.

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    Jeroen De Buck

    Full Text Available The sensitivity of current diagnostics for Johne's disease, a slow, progressing enteritis in ruminants caused by Mycobacterium avium subsp. paratuberculosis (MAP, is too low to reliably detect all infected animals in the subclinical stage. The objective was to identify individual metabolites or metabolite profiles that could be used as biomarkers of early MAP infection in ruminants. In a monthly follow-up for 17 months, calves infected at 2 weeks of age were compared with aged-matched controls. Sera from all animals were analyzed by 1H nuclear magnetic resonance spectrometry. Spectra were acquired, processed, and quantified for analysis. The concentration of many metabolites changed over time in all calves, but some metabolites only changed over time in either infected or non-infected groups and the change in others was impacted by the infection. Hierarchical multivariate statistical analysis achieved best separation between groups between 300 and 400 days after infection. Therefore, a cross-sectional comparison between 1-year-old calves experimentally infected at various ages with either a high- or a low-dose and age-matched non-infected controls was performed. Orthogonal Projection to Latent Structures Discriminant Analysis (OPLS DA yielded distinct separation of non-infected from infected cattle, regardless of dose and time (3, 6, 9 or 12 months after infection. Receiver Operating Curves demonstrated that constructed models were high quality. Increased isobutyrate in the infected cattle was the most important agreement between the longitudinal and cross-sectional analysis. In general, high- and low-dose cattle responded similarly to infection. Differences in acetone, citrate, glycerol and iso-butyrate concentrations indicated energy shortages and increased fat metabolism in infected cattle, whereas changes in urea and several amino acids (AA, including the branched chain AA, indicated increased protein turnover. In conclusion, metabolomics

  19. Experimental infection with the small intestinal trematode, Haplorchis pumilio, in young dogs

    DEFF Research Database (Denmark)

    Nissen, Sofie; Nguyen, Lan Anh Thi; Dalsgaard, Anders

    2013-01-01

    included as uninfected controls. Faecal examination for eggs was performed twice weekly using a sieving and sedimentation technique. Body temperature and weight of the dogs were measured as was total white blood cells, blood eosinophils and packed cell volume. Subsets of dogs were examined post......Fishborne zoonotic trematodes (FZT) are highly prevalent in Southeast Asia. Recent studies on the role of domestic animals in the transmission of FZT in Northern Vietnam found that dogs, mainly infected with Haplorchis pumilio, contributed widely to the transmission of FZT. On this background, we...... conducted an experimental infection with H. pumilio to elucidate population dynamics and host reactions in dogs. Eight household-reared dogs (3-6 months old), were each orally infected with 500 H. pumilio metacercariae obtained by artificial digestion of naturally infected fish. Another eight dogs were...

  20. Experimental infection of South American camelids with bluetongue virus serotype 8.

    Science.gov (United States)

    Schulz, Claudia; Eschbaumer, Michael; Rudolf, Miriam; König, Patricia; Keller, Markus; Bauer, Christian; Gauly, Matthias; Grevelding, Christoph G; Beer, Martin; Hoffmann, Bernd

    2012-01-27

    Bluetongue (BT) is an infectious, non-contagious disease of wild and domestic ruminants. It is caused by bluetongue virus (BTV) and transmitted by Culicoides biting midges. Since 1998, BT has been emerging throughout Europe, threatening not only the naïve ruminant population. Historically, South American camelids (SAC) were considered to be resistant to BT disease. However, recent fatalities related to BTV in captive SAC have raised questions about their role in BTV epidemiology. Data on the susceptibility of SAC to experimental infection with BTV serotype 8 (BTV-8) were collected in an animal experiment. Three alpacas (Vicugna pacos) and three llamas (Lama glama) were experimentally infected with BTV-8. They displayed very mild clinical signs. Seroconversion was first measured 6-8 days after infection (dpi) by ELISA, and neutralising antibodies appeared 10-13 dpi. BTV-8 RNA levels in blood were very low, and quickly cleared after seroconversion. However, spleens collected post-mortem were still positive for BTV RNA, over 71 days after the last detection in blood samples. Virus isolation was only possible from blood samples of two alpacas by inoculation of highly sensitive interferon alpha/beta receptor-deficient (IFNAR(-/-)) mice. An in vitro experiment demonstrated that significantly lower amounts of BTV-8 adsorb to SAC blood cells than to bovine blood cells. Although this experiment showed that SAC are generally susceptible to a BTV-8 infection, it indicates that these species play a negligible role in BTV epidemiology. Copyright © 2011 Elsevier B.V. All rights reserved.

  1. Nutritional Status Driving Infection by Trypanosoma cruzi: Lessons from Experimental Animals

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    Guilherme Malafaia

    2011-01-01

    Full Text Available This paper reviews the scientific knowledge about protein-energy and micronutrient malnutrition in the context of Chagas disease, especially in experimental models. The search of articles was conducted using the electronic databases of SciELO (Scientific Electronic Library Online, PubMed and MEDLINE published between 1960 and March 2010. It was possible to verify that nutritional deficiencies (protein-energy malnutrition and micronutrient malnutrition exert a direct effect on the infection by T. cruzi. However, little is known about the immunological mechanisms involved in the relationship “nutritional deficiencies and infection by T. cruzi”. A hundred years after the discovery of Chagas disease many aspects of this illness still require clarification, including the effects of nutritional deficiencies on immune and pathological mechanisms of T. cruzi infection.

  2. Experimental infection of Rickettsia parkeri in the Rhipicephalus microplus tick.

    Science.gov (United States)

    Cordeiro, Matheus Dias; de Azevedo Baêta, Bruna; Cepeda, Patricia Barizon; Teixeira, Rafaella Câmara; Ribeiro, Carla Carolina Dias Uzedo; de Almeida Valim, Jaqueline Rodrigues; Pinter, Adriano; da Fonseca, Adivaldo Henrique

    2018-01-01

    This study aimed to evaluate, by means of artificial feeding, the interaction between a pathogenic rickettsia and the hard tick R. microplus. We used partially engorged females fed on calves free of Rickettsia spp. Group 1 (G1), containing 20 ticks, was fed bovine blood only. Group 2 (G2), containing 20 ticks, was fed blood containing uninfected VERO cells, and group 3 (G3), containing 40 ticks, was fed blood containing VERO cells infected with Rickettsia parkeri. Biological parameters of the non-parasitic phase and a possible bacterial transmission to the tick eggs and to guinea pigs were evaluated. At the end of oviposition, all G3 females were PCR-positive for genes specific for the genus Rickettsia. Although no guinea pigs were infected, the experimental infection of R. microplus by R. parkeri caused a deleterious effect on the oviposition and provided the first report of transovarian transmission of rickettsia in this tick. Copyright © 2017 Elsevier GmbH. All rights reserved.

  3. Experimental Infection with Sporulated Oocysts of Eimeria maxima (Apicomplexa: Eimeriidae) in Broiler

    Science.gov (United States)

    Brito, Luciana da S.; Pereira, Elder N.; da Silva, Augusta A.; Bentivóglio Costa Silva, Vinícius; Freitas, Fagner L. da C.

    2014-01-01

    Through this study we assessed the metabolic and pathological changes in broilers experimentally infected with oocysts of Eimeria maxima. To perform the experiment, we used 150 broiler strain cooB males, with ten days of age, were randomized according to weight and randomly assigned to two experimental groups: the control group was inoculated with 0.5 mL of distilled water; the infected group inoculated with 0.5 mL of solution containing 5 × 104 sporulated oocysts of Eimeria maxima. The live performance was evaluated on day 0 (day of inoculation), 5°, 10°, 15°, 25°, and 35° dpi, being slaughtered by cervical dislocation, fifteen birds/group. Although the sum in meat production was higher in the control group, the weight of the heart and gizzard of the experimental animals showed no significant difference, while the liver had difference on day 5°, 15°, and 35° dpi. The pathologic evaluation showed congested mucosa and presence of large amounts of mucus at 6 dpi. Therefore, it is concluded that the dose of 5 × 104  E. maxima inoculated in the experimental group was enough to cause harm to the animal organism. PMID:26464925

  4. Effect of some parasitic infection on neurotransmitters in the brain of experimentally infected mice before and after treatment.

    Science.gov (United States)

    Abdel Ghafar, A E; Elkowrany, S E; Salem, S A; Menaisy, A A; Fadel, W A; Awara, W M

    1996-08-01

    The effects of some parasitic infection (bilharziasis, toxocariasis and trichinosis) on the brain of experimentally infected mice were investigated. Eighty animals were classified into four groups, group I contained five non infected animals as a control group. The other groups each contained twenty-five mice infected with Schistosoma mansoni (group II), Toxocara canis (group III) and Trichinella spiralis (group IV). Each infected group was divided into two subgroups (a,b). Subgroup (a) left untreated and subgroups (b) treated by praziquantel (in group II) and mebendazole (in group III and IV). Histopathological and immunological examination using peroxidase antiperoxidase (PAP) technique and neurotransmitters estimation (nor-epinephrine, dopamine and serotonine) were carried. In the untreated animals, there were mild histopathological changes and mild antigenic deposition in subgroups (IIa and IIIa) and marked changes in subgroup (IVa). There were significant decrease in dopamine in subgroup (IIIa), not improved after treatment (subgroup IIIb) and significant decrease in nor-epinephrine and serotonine in subgroup (IVa) improved after treatment in subgroup (IVb). The neurotransmitters changes may explain the motor, behavioural and emotional changes that occurred with these parasites.

  5. Disease dynamics and bird migration--linking mallards Anas platyrhynchos and subtype diversity of the influenza A virus in time and space.

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    Gunnar Gunnarsson

    Full Text Available The mallard Anas platyrhynchos is a reservoir species for influenza A virus in the northern hemisphere, with particularly high prevalence rates prior to as well as during its prolonged autumn migration. It has been proposed that the virus is brought from the breeding grounds and transmitted to conspecifics during subsequent staging during migration, and so a better understanding of the natal origin of staging ducks is vital to deciphering the dynamics of viral movement pathways. Ottenby is an important stopover site in southeast Sweden almost halfway downstream in the major Northwest European flyway, and is used by millions of waterfowl each year. Here, mallards were captured and sampled for influenza A virus infection, and positive samples were subtyped in order to study possible links to the natal area, which were determined by a novel approach combining banding recovery data and isotopic measurements (δ(2H of feathers grown on breeding grounds. Geographic assignments showed that the core natal areas of studied mallards were in Estonia, southern and central Finland, and northwestern Russia. This study demonstrates a clear temporal succession of latitudes of natal origin during the course of autumn migration. We also demonstrate a corresponding and concomitant shift in virus subtypes. Acknowledging that these two different patterns were based in part upon different data, a likely interpretation worth further testing is that the early arriving birds with more proximate origins have different influenza A subtypes than the more distantly originating late autumn birds. If true, this knowledge would allow novel insight into the origins and transmission of the influenza A virus among migratory hosts previously unavailable through conventional approaches.

  6. Experimental models of acute infection and Toll-like receptor driven septic shock.

    Science.gov (United States)

    Ferstl, Ruth; Spiller, Stephan; Fichte, Sylvia; Dreher, Stefan; Kirschning, Carsten J

    2009-01-01

    Mainly Gram-negative and Gram-positive bacterial infections, but also other infections such as with fungal or viral pathogens, can cause the life-threatening clinical condition of septic shock. Transgression of the host immune response from a local level limited to the pathogen's place of entry to the systemic level is recognised as a major mode of action leading to sepsis. This view has been established upon demonstration of the capacity of specific pathogen-associated molecular patterns (PAMPs) to elicit symptoms of septic shock upon systemic administration. Immune stimulatory PAMPs are agonists of soluble, cytoplasmic, as well as/or cell membrane-anchored and/or -spanning pattern recognition receptors (PRRs) such as Toll-like receptors (TLRs). However, reflection of pathogen-host crosstalk triggering sepsis pathogenesis upon an infection by a host response to challenge with an isolated PAMP is incomplete. Therefore, an experimental model more reflective of pathogen-host interaction requires experimental host confrontation with a specific pathogen in its viable form resulting in a collective stimulation of a variety of specific PRRs. This chapter describes methods to analyse innate pathogen sensing by the host on both a cellular and systemic level.

  7. Technetium-99m stannous pyrophosphate imaging of experimental infective endocarditis

    International Nuclear Information System (INIS)

    Riba, A.L.; Downs, J.; Thakur, M.L.; Gottschalk, A.; Andriole, V.T.; Zaret, B.L.

    1978-01-01

    Technetium-99m stannous pyrophosphate (/sup 99m/Tc-PYP) cardiac scintigraphy was performed in 15 rabbits with experimental Streptococcus sanguis aortic-valve infective endocarditis. The animals were imaged five to seven days after the administration of bacteria, and in each case abnormal accumulation of the tracer was visualized in the region of the aortic valve. Three types of cardiac scintigraphic patterns were demonstrated: focal, multifocal, and extensive, each correlating well with the anatomical extent of the lesion as defined by gross pathology. Tissue distribution studies demonstrated a 30 +- 5.3 (mean +- SEM) fold excess of radionuclide uptake in the infective endocarditis lesion compared with that of normal myocardium. Imaging of excised hearts from four animals showed an excellent correlation with in vivo imaging as well as gross pathology. Five animals with nonbacterial thrombotic aortic valve endocarditis demonstrated similar scintigraphic and tissue distribution results. In contrast, four normal animals failed to demonstrate abnormal /sup 99m/Tc-PYP cardiac scintigrams or tissue uptake. This study demonstrates that /sup 99m/Tc-PYP cardiac scintigraphy is a sensitive technique to detect experimental aortic valve endocarditis

  8. Horses experimentally infected with Sarcocystis neurona develop altered immune responses in vitro.

    Science.gov (United States)

    Witonsky, Sharon G; Ellison, Siobhan; Yang, Jibing; Gogal, Robert M; Lawler, Heather; Suzuki, Yasuhiro; Sriranganathan, Namalwar; Andrews, Frank; Ward, Daniel; Lindsay, David S

    2008-10-01

    Equine protozoal myeloencephalitis (EPM) due to Sarcocystis neurona infection is 1 of the most common neurologic diseases in horses in the United States. The mechanisms by which most horses resist disease, as well as the possible mechanisms by which the immune system may be suppressed in horses that develop EPM, are not known. Therefore, the objectives of this study were to determine whether horses experimentally infected with S. neurona developed suppressed immune responses. Thirteen horses that were negative for S. neurona antibodies in serum and cerebrospinal fluid (CSF) were randomly assigned to control (n = 5) or infected (n = 8) treatment groups. Neurologic exams and cerebrospinal fluid analyses were performed prior to, and following, S. neurona infection. Prior to, and at multiple time points following infection, immune parameters were determined. All 8 S. neurona-infected horses developed clinical signs consistent with EPM, and had S. neurona antibodies in the serum and CSF. Both infected and control horses had increased percentages (P < 0.05) of B cells at 28 days postinfection. Infected horses had significantly decreased (P < 0.05) proliferation responses as measured by thymidine incorporation to nonspecific mitogens phorbol myristate acetate (PMA) and ionomycin (I) as soon as 2 days postinfection.

  9. Experimental infection of cattle, sheep and pigs with 'Hobi'-like pestivirus.

    Science.gov (United States)

    Decaro, Nicola; Mari, Viviana; Lucente, Maria Stella; Sciarretta, Rossana; Moreno, Ana; Armenise, Carlo; Losurdo, Michele; Camero, Michele; Lorusso, Eleonora; Cordioli, Paolo; Buonavoglia, Canio

    2012-03-23

    To date, limited information is available on the ability of 'Hobi'-like pestiviruses (putative bovine viral diarrhoea 3) to infect and cause disease in animal species traditionally affected by pestiviruses. In order to obtain new insights into host range and pathogenic potential of this atypical pestivirus, BVDV-seronegative calves (n=5), lambs (n=5) and piglets (n=5) were experimentally infected with the European 'Hobi'-like strain Italy-1/10-1, whereas two animals per species served as uninfected controls. Appearance of clinical signs, leukopenia, viremia, viral shedding and seroconversion were monitored for 28 days post-infection. Calves and lambs were successfully infected, displaying respiratory signs (nasal discharge), moderate hyperthermia and leukopenia, viremia and viral shedding through the nasal and faecal routes. Antibody responses were observed in both animal species by ELISA and virus neutralisation assays. In contrast, inoculated piglets did not display any clinical signs nor leukopenia and viral RNA was not detected in any biological samples. Nevertheless, the presence of detectable antibodies by virus neutralisation accounted for a successful, albeit limited infection of these animals. Copyright © 2011 Elsevier B.V. All rights reserved.

  10. Experimental feline enteric coronavirus infection reveals an aberrant infection pattern and shedding of mutants with impaired infectivity in enterocyte cultures

    Science.gov (United States)

    Desmarets, Lowiese M. B.; Vermeulen, Ben L.; Theuns, Sebastiaan; Conceição-Neto, Nádia; Zeller, Mark; Roukaerts, Inge D. M.; Acar, Delphine D.; Olyslaegers, Dominique A. J.; Van Ranst, Marc; Matthijnssens, Jelle; Nauwynck, Hans J.

    2016-01-01

    Feline infectious peritonitis (FIP) results from mutations in the viral genome during a common feline enteric coronavirus (FECV) infection. Since many virological and immunological data on FECV infections are lacking, the present study investigated these missing links during experimental infection of three SPF cats with FECV strain UCD. Two cats showed mild clinical signs, faecal shedding of infectious virus from 4 dpi, a cell-associated viraemia at inconsistent time points from 5 dpi, a highly neutralising antibody response from 9 dpi, and no major abnormalities in leukocyte numbers. Faecal shedding lasted for 28–56 days, but virus shed during this stage was less infectious in enterocyte cultures and affected by mutations. Remarkably, in the other cat neither clinical signs nor acute shedding were seen, but virus was detected in blood cells from 3 dpi, and shedding of non-enterotropic, mutated viruses suddenly occurred from 14 dpi onwards. Neutralising antibodies arose from 21 dpi. Leukocyte numbers were not different compared to the other cats, except for the CD8+ regulatory T cells. These data indicate that FECV can infect immune cells even in the absence of intestinal replication and raise the hypothesis that the gradual adaptation to these cells can allow non-enterotropic mutants to arise. PMID:26822958

  11. Differences in pathogenicity, response to vaccination, and innate immune responses in different types of ducks infected with a virulent H5N1 highly pathogenic avian influenza virus from Vietnam.

    Science.gov (United States)

    Cagle, Caran; Wasilenko, Jamie; Adams, Sean C; Cardona, Carol J; To, Thanh Long; Nguyen, Tung; Spackman, Erica; Suarez, David L; Smith, Diane; Shepherd, Eric; Roth, Jason; Pantin-Jackwood, Mary J

    2012-09-01

    In a previous study, we found clear differences in pathogenicity and response to vaccination against H5N1 highly pathogenic avian influenza (HPAI; HA dade 2.3.4) between Pekin (Anas platyrhynchos var. domestica) and Muscovy (Cairina moschata) ducks vaccinated using a commercial inactivated vaccine (Re-1). The objective of the present study was to further investigate the pathogenicity of H5N1 HPAI viruses in different species of ducks by examining clinical signs and innate immune responses to infection with a different strain of H5N1 HPAI virus (HA clade 1) in two domestic ducks, Pekin and Muscovy, and one wild-type duck, mallard (Anas platyrhynchos). Protection conferred by vaccination using the Re-1 vaccine against infection with this virus was also compared between Pekin and Muscovy ducks. Differences in pathogenicity were observed among the virus-infected ducks, as the Muscovy ducks died 2 days earlier than did the Pekin and mallard ducks, and they presented more-severe neurologic signs. Conversely, the Pekin and mallard ducks had significantly higher body temperatures at 2 days postinfection (dpi) than did the Muscovy ducks, indicating possible differences in innate immune responses. However, similar expression of innate immune-related genes was found in the spleens of virus-infected ducks at this time point. In all three duck species, there was up-regulation of IFN-alpha, IFN-gamma, IL-6, CCL19, RIG-I, and MHC class I and down-regulation of MHC class II, but variable expression of IL-18 and TLR7. As in our previous study, vaccinated Muscovy ducks showed less protection against virus infection than did Pekin ducks, as evidenced by the higher mortality and higher number of Muscovy ducks shedding virus when compared to Pekin ducks. In conclusion, infection with an H5N1 HPAI virus produced a systemic infection with high mortality in all three duck species; however, the disease was more severe in Muscovy ducks, which also had a poor response to vaccination. The

  12. Experimental and natural infections in MyD88- and IRAK-4-deficient mice and humans

    Science.gov (United States)

    von Bernuth, Horst; Picard, Capucine; Puel, Anne; Casanova, Jean-Laurent

    2013-01-01

    Most Toll-like-receptors (TLRs) and interleukin-1 receptors (IL-1Rs) signal via myeloid differentiation primary response 88 (MyD88) and interleukin-1 receptor-associated kinase 4 (IRAK-4). The combined roles of these two receptor families in the course of experimental infections have been assessed in MyD88- and IRAK-4-deficient mice for almost fifteen years. These animals have been shown to be susceptible to 46 pathogens: 27 bacteria, 8 viruses, 7 parasites, and 4 fungi. Humans with inborn MyD88 or IRAK-4 deficiency were first identified in 2003. They suffer from naturally occurring life-threatening infections caused by a small number of bacterial species, although the incidence and severity of these infections decrease with age. Mouse TLR- and IL-1R-dependent immunity mediated by MyD88 and IRAK-4 seems to be vital to combat a wide array of experimentally administered pathogens at most ages. By contrast, human TLR- and IL-1R-dependent immunity mediated by MyD88 and IRAK-4 seems to be effective in the natural setting against only a few bacteria and is most important in infancy and early childhood. The roles of TLRs and IL-1Rs in protective immunity deduced from studies in mutant mice subjected to experimental infections should therefore be reconsidered in the light of findings for natural infections in humans carrying mutations as discussed in this review. PMID:23255009

  13. Anatomopathological study in BALB/c mice brains experimentally infected with Toxoplasma gondii

    Directory of Open Access Journals (Sweden)

    Marcos Gontijo da Silva

    Full Text Available Toxoplasmosis is one of the most important diseases of the nervous central system, leading to severe symptoms and, many times, irreversible sequelae. This work demonstrated the main anatomopathological lesions caused by Toxoplasma gondii in brains from experimentally infected BALB/c mice. We analyzed 51 cases of mice that developed toxoplasmosis after experimental infection by intraperitoneal inoculation of blood, amniotic liquid and cerebrospinal fluid from fetuses, newly born children and pregnant women with clinical and laboratory signals of toxoplasmosis. In all experiments where we detected the parasite in mice we also detected pathological lesions in the animal brains with great polymorphism between experiments. Edema was the most found lesion in all cases. Besides, it was possible to demonstrate the inflammatory process in 82.4% of cases and necrosis in 64.7% of cases, in agreement with the literature that describes severe neurological damage in its hosts.

  14. Experimental infection of serotine bats (Eptesicus serotinus) with European bat lyssavirus type 1a.

    Science.gov (United States)

    Freuling, C; Vos, A; Johnson, N; Kaipf, I; Denzinger, A; Neubert, L; Mansfield, K; Hicks, D; Nuñez, A; Tordo, N; Rupprecht, C E; Fooks, A R; Müller, T

    2009-10-01

    The serotine bat (Eptesicus serotinus) accounts for the vast majority of bat rabies cases in Europe and is considered the main reservoir for European bat lyssavirus type 1 (EBLV-1, genotype 5). However, so far the disease has not been investigated in its native host under experimental conditions. To assess viral virulence, dissemination and probable means of transmission, captive bats were infected experimentally with an EBLV-1a virus isolated from a naturally infected conspecific from Germany. Twenty-nine wild caught bats were divided into five groups and inoculated by intracranial (i.c.), intramuscular (i.m.) or subcutaneous (s.c.) injection or by intranasal (i.n.) inoculation to mimic the various potential routes of infection. One group of bats was maintained as uninfected controls. Mortality was highest in the i.c.-infected animals, followed by the s.c. and i.m. groups. Incubation periods varied from 7 to 26 days depending on the route of infection. Rabies did not develop in the i.n. group or in the negative-control group. None of the infected bats seroconverted. Viral antigen was detected in more than 50% of the taste buds of an i.c.-infected animal. Shedding of viable virus was measured by virus isolation in cell culture for one bat from the s.c. group at 13 and 14 days post-inoculation, i.e. 7 days before death. In conclusion, it is postulated that s.c. inoculation, in nature caused by bites, may be an efficient way of transmitting EBLV-1 among free-living serotine bats.

  15. Heavy metals in tissues of water fowl from the Chesapeake Bay, USA. [Clangula hyemalis; Melanitta deglandi; Anas platyrhynchos; Anas rubripes; Anas strepera

    Energy Technology Data Exchange (ETDEWEB)

    Di Giulio, R; Scanlon, P F

    1984-01-01

    Concentrations of cadmium, lead, copper and zinc were measured in 774 livers, 266 kidneys and 271 ulnar bones from 15 species of ducks obtained from the Chesapeake Bay region. A major purpose of this study was to elucidate relationships between food habits and tissue accumulations of heavy metals in Chesapeake Bay water fowl. Liver and kidney concentrations of cadmium were highest among two carnivorous seaduck species, Clangula hyemalis and Melanitta deglandi. In contrast, lead concentrations in tissues were generally highest in largely herbivorous species, such as Anas platyrhynchos, Anas rubripes and Anas strepera. Spent shot may be an important source for tissue burdens of lead in these ducks. No marked trends were observed between food habits and tissue concentrations of the nutrient elements, copper and zinc.

  16. Lipid and glucose metabolism of broilers (Gallus gallus domesticus experimentally infected with Eimeria acervulina Tyzzer, 1929 oocysts

    Directory of Open Access Journals (Sweden)

    FLC Freitas

    2008-09-01

    Full Text Available Lipid and glucose metabolism of 76 ten-day-old Cobb male broilers, experimentally infected with Eimeria acervulina, was studied for 30 days. Birds were distributed in 2 groups: one infected with 1x10(6 E. acervulina sporulated oocysts, and the other inoculated with distilled water. Pathological e biochemical liver changes were assessed, as well as plasma glucose concentrations and total cholesterol, HDL, LDL, VLDL, fatty-acid, and triglyceride levels in the serum. The infected broilers presented hypoglycemia associated with a reduction in liver glycogen. In addition, these birds developed fatty liver, and there were changes in all lipid classes in the serum. Lipid and glucose metabolism was dramatically changed in broilers experimentally infected with 1x10(6 E. acervulina oocysts.

  17. Experimental Andes virus infection in deer mice: characteristics of infection and clearance in a heterologous rodent host.

    Directory of Open Access Journals (Sweden)

    Jessica R Spengler

    Full Text Available New World hantaviruses can cause hantavirus cardiopulmonary syndrome with high mortality in humans. Distinct virus species are hosted by specific rodent reservoirs, which also serve as the vectors. Although regional spillover has been documented, it is unknown whether rodent reservoirs are competent for infection by hantaviruses that are geographically separated, and known to have related, but distinct rodent reservoir hosts. We show that Andes virus (ANDV of South America, carried by the long tailed pygmy rice rat (Oligoryzomys longicaudatus, infects and replicates in vitro and in vivo in the deer mouse (Peromyscus maniculatus, the reservoir host of Sin Nombre virus (SNV, found in North America. In experimentally infected deer mice, viral RNA was detected in the blood, lung, heart and spleen, but virus was cleared by 56 days post inoculation (dpi. All of the inoculated deer mice mounted a humoral immune response by 14 dpi, and produced measurable amounts of neutralizing antibodies by 21 dpi. An up-regulation of Ccl3, Ccl4, Ccl5, and Tgfb, a strong CD4⁺ T-cell response, and down-regulation of Il17, Il21 and Il23 occurred during infection. Infection was transient with an absence of clinical signs or histopathological changes. This is the first evidence that ANDV asymptomatically infects, and is immunogenic in deer mice, a non-natural host species of ANDV. Comparing the immune response in this model to that of the immune response in the natural hosts upon infection with their co-adapted hantaviruses may help clarify the mechanisms governing persistent infection in the natural hosts of hantaviruses.

  18. Laboratory experimental infection of sheep to Ornithobilharzia turkestanicum and its confirmation using post-mortem examination and histopathology

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    gholamreza karimi

    2014-11-01

    Full Text Available Ornithobilharzia turkestanicum from genus Ornithobilharzia genus and family Schistosomatidae is an important agent of parasitological infection in sheep. This parasite has been reported from Russia, China, Turkestan (Kazakhstan, Kyrgyzstan, Turkmenistan and Uzbekistan, Pakistan, Iraq, Turkey and Iran. Parasitological infection due to this agent could be one of the important factors of decreasing the production rate of livestock in Iran. The purpose of this study, was to experimentally infect sheep with this parasite and confirm the infection by post-mortem examination and Histopathology which was done successfully. Twenty five sheep were used in the study of which 10 sheep were experimentally infected by Ornithobilharzia turkestanikum using subcutaneous injection and 10 sheep by skin contact method and the other 5 sheep were kept as control. Result of post-mortem and Histopathology during a one year period confirmed that all of sheep were infected and adult worm, were seen in their mesentery. Mean number of cercaria used for inducing the infection was 6425 and 462 adult worms were collected post-mortem. There was no significant relationship between the number of cercaria and adult worms collected. Male sheep were more infected than female.

  19. Carbohydrate-rich high-molecular-mass antigens are strongly recognized during experimental Histoplasma capsulatum infection

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    Fabrine Sales Massafera Tristão

    2012-04-01

    Full Text Available INTRODUCTION: During histoplasmosis, Histoplasma capsulatum soluble antigens (CFAg can be naturally released by yeast cells. Because CFAg can be specifically targeted during infection, in the present study we investigated CFAg release in experimental murine histoplasmosis, and evaluated the host humoral immune response against high-molecular-mass antigens (hMMAg. >150 kDa, the more immunogenic CFAg fraction. METHODS: Mice were infected with 2.2x10(4 H. capsulatum IMT/HC128 yeast cells. The soluble CFAg, IgG anti-CFAg, IgG anti-hMMAg, and IgG-hMMAg circulating immune complexes (CIC levels were determined by enzymelinked immunosorbent assay, at days 0, 7, 14, and 28 post-infection. RESULTS: We observed a progressive increase in circulating levels of CFAg, IgG anti-CFAg, IgG anti-hMMAg, and IgG-hMMAg CIC after H. capsulatum infection. The hMMAg showed a high percentage of carbohydrates and at least two main immunogenic components. CONCLUSIONS: We verified for the first time that hMMAg from H. capsulatum IMT/HC128 strain induce humoral immune response and lead to CIC formation during experimental histoplasmosis.

  20. Persistence of experimental Rocio virus infection in the golden hamster (Mesocricetus auratus

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    Daniele Freitas Henriques

    2012-08-01

    Full Text Available Rocio virus (ROCV is an encephalitic flavivirus endemic to Brazil. Experimental flavivirus infections have previously demonstrated a persistent infection and, in this study, we investigated the persistence of ROCV infection in golden hamsters (Mesocricetus auratus. The hamsters were infected intraperitoneally with 9.8 LD50/0.02 mL of ROCV and later anaesthetised and sacrificed at various time points over a 120-day period to collect of blood, urine and organ samples. The viral titres were quantified by real-time-polymerase chain reaction (qRT-PCR. The specimens were used to infect Vero cells and ROCV antigens in the cells were detected by immunefluorescence assay. The levels of antibodies were determined by the haemagglutination inhibition technique. A histopathological examination was performed on the tissues by staining with haematoxylin-eosin and detecting viral antigens by immunohistochemistry (IHC. ROCV induced a strong immune response and was pathogenic in hamsters through neuroinvasion. ROCV was recovered from Vero cells exposed to samples from the viscera, brain, blood, serum and urine and was detected by qRT-PCR in the brain, liver and blood for three months after infection. ROCV induced histopathological changes and the expression of viral antigens, which were detected by IHC in the liver, kidney, lung and brain up to four months after infection. These findings show that ROCV is pathogenic to golden hamsters and has the capacity to cause persistent infection in animals after intraperitoneal infection.

  1. Experimental infection with Brazilian Newcastle disease virus strain in pigeons and chickens

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    Adriano de Oliveira Torres Carrasco

    2016-03-01

    Full Text Available Abstract This study was designed with the goal of adding as much information as possible about the role of pigeons (Columba livia and chickens (Gallus gallus in Newcastle disease virus epidemiology. These species were submitted to direct experimental infection with Newcastle disease virus to evaluate interspecies transmission and virus-host relationships. The results obtained in four experimental models were analyzed by hemagglutination inhibition and reverse transcriptase polymerase chain reaction for detection of virus shedding. These techniques revealed that both avian species, when previously immunized with a low pathogenic Newcastle disease virus strain (LaSota, developed high antibody titers that significantly reduced virus shedding after infection with a highly pathogenic Newcastle disease virus strain (São Joao do Meriti and that, in chickens, prevent clinical signs. Infected pigeons shed the pathogenic strain, which was not detected in sentinel chickens or control birds. When the presence of Newcastle disease virus was analyzed in tissue samples by RT-PCR, in both species, the virus was most frequently found in the spleen. The vaccination regimen can prevent clinical disease in chickens and reduce viral shedding by chickens or pigeons. Biosecurity measures associated with vaccination programs are crucial to maintain a virulent Newcastle disease virus-free status in industrial poultry in Brazil.

  2. Vertebrate host specificity and experimental vectors of Plasmodium (Novyella) kempi sp. n. from the eastern wild turkey in Iowa.

    Science.gov (United States)

    Christensen, B M; Barnes, H J; Rowley, W A

    1983-07-01

    Vertebrate host specificity, experimental laboratory vectors, and a description of Plasmodium (Novyella) kempi sp. n. from eastern wild turkeys (Meleagris gallopavo silvestris Vieillot) in Iowa are presented. Plasmodium kempi is infective for domestic turkeys, bobwhites (Colinus virginianus), chukars (Alectoris graeca), guinea fowl (Numida meleagris), peacocks (Pavo cristatus), and canaries (Serinus canaria), produces a transient infection in mallards (Anas platyrhynchos) and domestic geese (Anser anser), but will not infect ring-necked pheasants (Phasianus colchicus), pigeons (Columba livia), Japanese quail (Coturnix coturnix), leghorn white chickens (Gallus gallus), or starlings (Sturnus vulgaris). Oocysts and (or) sporozoites were recovered from 68% (84/124) and 98% (60/61) of the Culex pipiens pipiens and C. tarsalis examined, respectively. Oocysts developed faster and sporozoites invaded the salivary glands sooner in C. tarsalis (6 days) than in C. p. pipiens (7 days). Culex tarsalis transmitted P. kempi more effectively than C. p. pipiens, although both species were capable of transmitting the parasite by natural feeding. Oocysts developed and sporozoites also were produced in C. restuans, but its ability to transmit the parasite was not determined. Aedes aegypti (Rockefeller strain) and A. triseriatus were refractive to P. kempi. Plasmodium kempi produces trophozoites with large refractile globules and fine cytoplasmic extensions, mature schizonts in the form of a condensed fan containing four to eight nuclei (usually 5), and elongate gametocytes with irregular borders. All stages are confined almost exclusively to mature erythrocytes, with no effect on host cell size or position of host cell nucleus. Plasmodium kempi is most similar morphologically to P. (Novyella) hexamerium and P. (Novyella) vaughani. It differs from P. hexamerium in having large refractile globules in trophozoites and immature schizonts, an inability to infect starlings, an absence of

  3. Pathogenesis of Riemerella anatipestifer in turkeys after experimental mono-infection via respiratory routes or dual infection together with the avian metapneumovirus.

    Science.gov (United States)

    Rubbenstroth, Dennis; Ryll, Martin; Behr, Klaus-Peter; Rautenschlein, Silke

    2009-12-01

    Riemerella anatipestifer (RA) is the causative agent of septicaemic and exudative diseases in a variety of bird species. Despite numerous outbreaks, little is known about the pathogenicity of RA for turkeys. We investigated the development of RA-induced disease in commercial turkey poults following RA inoculation via different respiratory routes. Inoculation by aerosol or injection into the abdominal air sac led to systemic infection and mild gross lesions, including pericarditis, epicarditis and airsacculitis, which were less pronounced compared with field outbreaks. It was speculated, that viral pathogens, such as the avian metapneumovirus (aMPV), may exacerbate RA pathogenesis under field conditions. We inoculated turkey poults with virulent aMPV. Subsequently, aMPV-infected and virus-free birds were exposed 3 to 5 days later to a high dose of RA by aerosol (>10(10) colony-forming units/ml in 8 ml aerosol per 11 or 12 birds) or were inoculated 4 days later with a low RA dose (10(4.9) colony-forming units per bird) via the intranasal route. Intranasal RA inoculation with the low bacterial dose led to a respiratory and systemic RA infection in aMPV-infected birds, while virus-free birds remained RA-negative. Following exposure to a high RA dose by aerosol, aMPV-infected groups showed slightly enhanced incidences of gross lesions and RA re-isolation. The present study clearly confirms that RA is pathogenic for turkeys after experimental inoculation via respiratory routes, which are speculated to be the natural route of infection. However, experimental models in this study did not reproduce the severity of RA-related disease as observed under field conditions, which emphasizes the importance of other contributing factors. aMPV-induced respiratory lesions may serve as a predisposing factor for the establishment of RA infection, since they favour colonization of the bacterium.

  4. Coronative antibody tires in sera of healthy adults and experimentally infected volunteers.

    Science.gov (United States)

    Bradburne, A F; Somerset, B A

    1972-06-01

    Six coronaviruses isolated in the U.S.A. have been inoculated into volunteers and all produced colds. Between 10 and 20% of infected volunteers developed heterologous antibody responses after these and other experimental infections with coronaviruses. The haemagglutination-inhibition test with the OC43 virus strain was found to detect antibody rises after infection with a variety of strains.Studies on normal adult sera taken between 1965 and 1970 revealed a high frequency of neutralizing antibody to one strain (229 E) and a frequency of HI antibody to strain OC43 which fluctuated from year to year. Complement-fixing antibodies to these two viruses were also found, revealing an apparent increase in the activity of coronaviruses in the general population of the U.K., during the winter of 1968-9.

  5. Experimental gonococcal infection in male volunteers: Cumulative experience with Neisseria gonorrhoeae strains FA1090 and MS11mkC

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    Marcia Metzgar Hobbs

    2011-05-01

    Full Text Available Experimental infection of male volunteers with Neisseria gonorrhoeae is safe and reproduces the clinical features of naturally acquired gonococcal urethritis. Human inoculation studies have helped define the natural history of experimental infection with two well-characterized strains of N. gonorrhoeae, FA1090 and MS11mkC. The human model has proved useful for testing the importance of putative gonococcal virulence factors for urethral infection in men. Studies with isogenic mutants have improved our understanding of the requirements for gonococcal LOS structures, pili, opacity proteins, IgA1 protease and the ability of infecting organisms to obtain iron from human transferrin and lactoferrin during uncomplicated urethritis. The model also presents opportunities to examine innate host immune responses that may be exploited or improved in development and testing of gonococcal vaccines. Here we review results to date with human experimental gonorrhea.

  6. Experimental rhinovirus infection in volunteers.

    Science.gov (United States)

    Bardin, P G; Sanderson, G; Robinson, B S; Holgate, S T; Tyrrell, D A

    1996-11-01

    Experimental viral disease studies in volunteers have clarified many aspects of the pathogenesis of human viral disease. Recently, interest has focused on rhinovirus-associated asthma exacerbations, and new volunteer studies have suggested that airway responsiveness (AR) is enhanced during a cold. For scientific, ethical and safety reasons, it is important to use validated methods for the preparation of a virus inoculum and that the particular virological characteristics and host responses should not be altered. We have prepared a new human rhinovirus (HRV) inoculum using recent guidelines and assessed whether disease characteristics (for example, severity of colds or changes in AR) were retained. Studies were conducted in 25 clinically healthy volunteers using a validated HRV inoculum in the first 17 and a new inoculum in the subsequent eight subjects. Severity of cold symptoms, nasal wash albumin levels and airway responsiveness were measured, and the new inoculum was prepared from nasal washes obtained during the cold. The new inoculum was tested using standard virological and serological techniques, as well as a polymerase chain reaction for Mycoplasma pneumoniae. No contaminating viruses or organisms were detected and the methods suggested were workable. Good clinical colds developed in 20 of the 25 subjects and median symptom scores were similar in the validated and new inoculum groups (18 and 17.5, respectively; p=0.19). All subjects shed virus, and there were no differences noted in viral culture scores, nasal wash albumin and rates of seroconversion in the two groups. Although airway responsiveness increased in both groups (p=0.02 and p=0.05), the degree of change was similar. We have performed experimental rhinovirus infection studies and demonstrated similar clinical disease in two inoculum groups. Amplified airway responsiveness was induced; continuing studies will define the mechanisms and suggest modes of treatment.

  7. Pathogenesis of reproductive failure induced by Trypanosoma vivax in experimentally infected pregnant ewes

    Science.gov (United States)

    2013-01-01

    The present study was aimed at investigating the effect of experimental infection by Trypanosoma vivax in different stages of pregnancy, determining the pathogenesis of reproductive failure, and confirming transplacental transmission. We used 12 pregnant ewes distributed into four experimental groups: G1, was formed by three ewes infected with T. vivax in the first third of pregnancy (30 days); G2 comprised three infected ewes in the final third of pregnancy (100 days); G3 and G4 were composed of three non-infected ewes with the same gestational period, respectively. Each ewe of G1 and G2 was inoculated with 1.25 × 105 tripomastigotes. Clinical examination, determination of parasitemia, serum biochemistry (albumin, total protein, glucose, cholesterol, and urea), packed cell volume (PCV), serum progesterone, and pathological examination were performed. Placenta, amniotic fluid, blood and tissues from the fetuses and stillbirths were submitted to PCR. Two ewes of G1 (Ewe 1 and 3) presented severe infection and died in the 34th and 35th days post-infection (dpi), respectively; but both fetuses were recovered during necropsy. In G2, Ewe 5 aborted two fetuses on the 130th day (30 dpi) of pregnancy; and Ewe 6 aborted one fetus in the 140th day (40 dpi) of gestation. Ewes 2 and 4 delivered two weak lambs that died five days after birth. Factors possibly involved with the reproductive failure included high parasitemia, fever, low PCV, body score, serum glucose, total protein, cholesterol, and progesterone. Hepatitis, pericarditis, and encephalitis were observed in the aborted fetuses. The presence of T. vivax DNA in the placenta, amniotic fluid, blood, and tissues from the fetuses confirms the transplacental transmission of the parasite. Histological lesion in the fetuses and placenta also suggest the involvement of the parasite in the etiopathogenesis of reproductive failure in ewes. PMID:23289625

  8. Small sarcocysts can be a feature of experimental infections with Sarcocystis neurona merozoites.

    Science.gov (United States)

    Marsh, Antoinette E; Chaney, Sarah B; Howe, Daniel K; Saville, William J; Reed, Stephen M

    2017-10-15

    Several reports indicate the presence of small tissue cysts associated with Sarcocystis neurona infections. Several failed attempts to develop tissue cysts in potential intermediate host using in vitro derived parasites originally isolated from horses with equine protozoal myeloencephalitis suggest that the experimental methods to achieve bradyzoites with those isolates was not possible. Those prior studies reported the lack of detectable sarcocysts based on histology and in vivo feeding trials. A recent report of successful production and detection of small sarcocysts triggered us to review archived tissues from earlier experimental infection studies. The retrospective review sought to determine if small sized sarcocysts were not detected due to their relatively smaller size and infrequency as compared to larger sized sarcocysts produced with other isolates in these experimental inoculation trials. Tissues from two prior in vivo inoculation studies, involving in vitro-produced parasites inoculated into laboratory-reared cats and raccoons, were re-examined by immunohistochemistry staining to more easily detect the tissue cysts. In the experimental cat study no small tissue cysts were seen, consistent with the original publication results. However, in the experimental raccoon study, one raccoon inoculated with an EPM-derived isolate, SN-UCD1, had small sarcocysts not reported in the original publication. This retrospective study suggests that much closer scrutiny of tissues, including the use of immunohistochemistry on tissue sections is required to detect the smaller S. neurona sarcocysts associated with the experimental inoculations of the isolates originally derived from horses with EPM. Published by Elsevier B.V.

  9. Transplacental and oral transmission of wild-type bluetongue virus serotype 8 in cattle after experimental infection

    NARCIS (Netherlands)

    Backx, A.; Heutink, C.G.; Rooij, van E.M.A.; Rijn, van P.A.

    2009-01-01

    Potential vertical transmission of wild-type bluetongue virus serotype 8 (BTV-8) in cattle was explored in this experiment. We demonstrated transplacental transmission of wild-type BTV-8 in one calf and oral infection with BTV-8 in another calf. Following the experimental BTV-8 infection of seven

  10. The Strategy to Survive Primary Malaria Infection: An Experimental Study on Behavioural Changes in Parasitized Birds.

    Directory of Open Access Journals (Sweden)

    Andrey Mukhin

    Full Text Available Avian malaria parasites (Haemosporida, Plasmodium are of cosmopolitan distribution, and they have a significant impact on vertebrate host fitness. Experimental studies show that high parasitemia often develops during primary malaria infections. However, field studies only occasionally reveal high parasitemia in free-living birds sampled using the traditional methods of mist-netting or trapping, and light chronic infections predominate. The reason for this discrepancy between field observation and experimental data remains insufficiently understood. Since mist-netting is a passive capture method, two main parameters determine its success in sampling infected birds in wildlife, i. e. the presence of parasitized birds at a study site and their mobility. In other words, the trapping probability depends on the survival rate of birds and their locomotor activity during infection. Here we test (1 the mortality rate of wild birds infected with Plasmodium relictum (the lineage pSGS1, (2 the changes in their behaviour during presence of an aerial predator, and (3 the changes in their locomotor activity at the stage of high primary parasitemia.We show that some behavioural features which might affect a bird's survival during a predator attack (time of reaction, speed of flush flight and take off angle did not change significantly during primary infection. However, the locomotor activity of infected birds was almost halved compared to control (non-infected birds during the peak of parasitemia. We report (1 the markedly reduced mobility and (2 the 20% mortality rate caused by P. relictum and conclude that these factors are responsible for the underrepresentation of birds in mist nets and traps during the stage of high primary parasitemia in wildlife. This study indicates that the widespread parasite, P. relictum (pSGS1 influences the behaviour of birds during primary parasitemia. Experimental studies combined with field observations are needed to better

  11. The Strategy to Survive Primary Malaria Infection: An Experimental Study on Behavioural Changes in Parasitized Birds

    Science.gov (United States)

    Mukhin, Andrey; Palinauskas, Vaidas; Platonova, Elena; Kobylkov, Dmitry; Vakoliuk, Irina; Valkiūnas, Gediminas

    2016-01-01

    Avian malaria parasites (Haemosporida, Plasmodium) are of cosmopolitan distribution, and they have a significant impact on vertebrate host fitness. Experimental studies show that high parasitemia often develops during primary malaria infections. However, field studies only occasionally reveal high parasitemia in free-living birds sampled using the traditional methods of mist-netting or trapping, and light chronic infections predominate. The reason for this discrepancy between field observation and experimental data remains insufficiently understood. Since mist-netting is a passive capture method, two main parameters determine its success in sampling infected birds in wildlife, i. e. the presence of parasitized birds at a study site and their mobility. In other words, the trapping probability depends on the survival rate of birds and their locomotor activity during infection. Here we test (1) the mortality rate of wild birds infected with Plasmodium relictum (the lineage pSGS1), (2) the changes in their behaviour during presence of an aerial predator, and (3) the changes in their locomotor activity at the stage of high primary parasitemia.We show that some behavioural features which might affect a bird's survival during a predator attack (time of reaction, speed of flush flight and take off angle) did not change significantly during primary infection. However, the locomotor activity of infected birds was almost halved compared to control (non-infected) birds during the peak of parasitemia. We report (1) the markedly reduced mobility and (2) the 20% mortality rate caused by P. relictum and conclude that these factors are responsible for the underrepresentation of birds in mist nets and traps during the stage of high primary parasitemia in wildlife. This study indicates that the widespread parasite, P. relictum (pSGS1) influences the behaviour of birds during primary parasitemia. Experimental studies combined with field observations are needed to better understand the

  12. Experimental infection and transmission of Leishmania by Lutzomyia cruzi (Diptera: Psychodidae: Aspects of the ecology of parasite-vector interactions.

    Directory of Open Access Journals (Sweden)

    Everton Falcão de Oliveira

    2017-02-01

    Full Text Available Several parameters should be addressed before incriminating a vector for Leishmania transmission. Those may include its ability to become infected by the same Leishmania species found in humans, the degree of attractiveness for reservoirs and humans and capacity to sustain parasite infection under laboratory conditions. This study evaluated the vectorial capacity of Lutzomyia cruzi for Leishmania infantum and gathered information on its ability to harbor L. amazonensis. Laboratory-reared Lu. cruzi were infected experimentally by feeding them on dogs infected naturally with L. infantum and hamsters infected with L. amazonensis. Sand fly attractiveness to dogs and humans was determined using wild caught insects. The expected daily survival of infected Lu. cruzi, the duration of the gonotrophic cycle, and the extrinsic incubation period were also investigated for both parasites. Vector competence was investigated for both Leishmania species. The mean proportion of female sand flies that fed on hosts was 0.40. For L. infantum and L. amazonensis, Lu. cruzi had experimental infection rates of 10.55% and 41.56%, respectively. The extrinsic incubation period was 3 days for both Leishmania species, regardless of the host. Survival expectancy of females infected with L. infantum and L. amazonensis after completing the gonotrophic cycle was 1.32 and 0.43, respectively. There was no association between L. infantum infection and sand fly longevity, but L. amazonensis-infected flies had significantly greater survival probabilities. Furthermore, egg-laying was significantly detrimental to survival. Lu. cruzi was found to be highly attracted to both dogs and humans. After a bloodmeal on experimentally infected hosts, both parasites were able to survive and develop late-stage infections in Lu. cruzi. However, transmission was demonstrated only for L. amazonensis-infected sand flies. In conclusion, Lu. cruzi fulfilled several of the requirements of vectorial

  13. Experimental infection and transmission of Leishmania by Lutzomyia cruzi (Diptera: Psychodidae): Aspects of the ecology of parasite-vector interactions.

    Science.gov (United States)

    Falcão de Oliveira, Everton; Oshiro, Elisa Teruya; Fernandes, Wagner de Souza; Murat, Paula Guerra; Medeiros, Márcio José de; Souza, Alda Izabel; Oliveira, Alessandra Gutierrez de; Galati, Eunice Aparecida Bianchi

    2017-02-01

    Several parameters should be addressed before incriminating a vector for Leishmania transmission. Those may include its ability to become infected by the same Leishmania species found in humans, the degree of attractiveness for reservoirs and humans and capacity to sustain parasite infection under laboratory conditions. This study evaluated the vectorial capacity of Lutzomyia cruzi for Leishmania infantum and gathered information on its ability to harbor L. amazonensis. Laboratory-reared Lu. cruzi were infected experimentally by feeding them on dogs infected naturally with L. infantum and hamsters infected with L. amazonensis. Sand fly attractiveness to dogs and humans was determined using wild caught insects. The expected daily survival of infected Lu. cruzi, the duration of the gonotrophic cycle, and the extrinsic incubation period were also investigated for both parasites. Vector competence was investigated for both Leishmania species. The mean proportion of female sand flies that fed on hosts was 0.40. For L. infantum and L. amazonensis, Lu. cruzi had experimental infection rates of 10.55% and 41.56%, respectively. The extrinsic incubation period was 3 days for both Leishmania species, regardless of the host. Survival expectancy of females infected with L. infantum and L. amazonensis after completing the gonotrophic cycle was 1.32 and 0.43, respectively. There was no association between L. infantum infection and sand fly longevity, but L. amazonensis-infected flies had significantly greater survival probabilities. Furthermore, egg-laying was significantly detrimental to survival. Lu. cruzi was found to be highly attracted to both dogs and humans. After a bloodmeal on experimentally infected hosts, both parasites were able to survive and develop late-stage infections in Lu. cruzi. However, transmission was demonstrated only for L. amazonensis-infected sand flies. In conclusion, Lu. cruzi fulfilled several of the requirements of vectorial capacity for L. infantum

  14. Highly pathogenic avian influenza virus (H5N1) in experimentally infected adult mute swans.

    Science.gov (United States)

    Kalthoff, Donata; Breithaupt, Angele; Teifke, Jens P; Globig, Anja; Harder, Timm; Mettenleiter, Thomas C; Beer, Martin

    2008-08-01

    Adult, healthy mute swans were experimentally infected with highly pathogenic avian influenza virus A/Cygnus cygnus/Germany/R65/2006 subtype H5N1. Immunologically naive birds died, whereas animals with preexisting, naturally acquired avian influenza virus-specific antibodies became infected asymptomatically and shed virus. Adult mute swans are highly susceptible, excrete virus, and can be clinically protected by preexposure immunity.

  15. Age-dependent differences in cytokine and antibody responses after experimental RSV infection in a bovine model

    DEFF Research Database (Denmark)

    Grell, S.N.; Riber, Ulla; Tjørnehøj, Kirsten

    2005-01-01

    Respiratory syncytial virus (RSV) causes severe respiratory disease in both infants and calves. As in humans, bovine RSV (BRSV) infections are most severe in the first 6 months of life. In this study, experimental infection with BRSV was performed in calves aged 1-5, 9-16 or 32-37 weeks. Compared...

  16. Alteration in the endogenous intestinal flora of swiss webster mice by experimental Angiostrongylus costaricensis infection

    Directory of Open Access Journals (Sweden)

    Vandack Nobre

    2004-11-01

    Full Text Available The association between worm infections and bacterial diseases has only recently been emphasized. This study examined the effect of experimental Angiostrongylus costaricensis infection on endogenous intestinal flora of Swiss Webster mice. Eight mice aging six weeks were selected for this experiment. Four were infected with A. costaricensis and the other four were used as controls. Twenty eight days after the worm infection, all mice in both groups were sacrificed and samples of the contents of the ileum and colon were obtained and cultured for aerobic and anaerobic bacteria. In the mice infected with A. costaricensis there was a significant increase in the number of bacteria of the endogenous intestinal flora, accompanied by a decrease in the number of Peptostreptococcus spp. This alteration in the intestinal flora of mice infected by the nematode may help to understand some bacterial infections described in humans.

  17. Experimental Infection of Taenia saginata eggs in Bali Cattle: Distribution and Density of Cysticercus bovis

    Directory of Open Access Journals (Sweden)

    Nyoman Sadra Dharmawan

    2009-12-01

    Full Text Available The objective of this study was to observe the development, distribution, and infection density ofTaenia saginata metacestodes in Bali cattle. Three Bali cattle were experimentally infected with T. saginataeggs which were collected from taeniasis patients. The experimental animal was inoculated with : i1000,00 T. saginata; ii 500,000 eggs; and iii 1,000,000 eggs, respectivelly 100,000 (cattle 1, 500,000(cattle 2, and 1,000,000 (cattle 3 T. saginata eggs, respectively. To observe the development of cysticerci,all cattle were slaughtered at 24 weeks post infection. To observe their distribution and density, slicingwas done to the cattle?s tissues. The study results showed that cysts were found distributed to all muscletissues and some visceral organs such as heart, diaphragm, lungs, and kidney of the cattle infected with100,000 and 500,000 T. saginata eggs. Density of the cyst was in the range of 11 to 95 cysts per 100 gramsof tissue. The highest density was noted in the heart (58/100 grams and in diaphragm (55/100 grams.This study has confirmed that T. saginata eggs derived from taeniasis patient in Bali, if infected to Balicattle can develop and spread to all muscle tissues and some visceral organs. From this study it wasconcluded that it is necessary to include the heart in the meat inspection at slaughter house for possibilityof T. saginata cyst infection.$?

  18. Intestinal colonization of broiler chickens by Campylobacter spp. in an experimental infection study

    DEFF Research Database (Denmark)

    Bahrndorff, Simon; Garcia Clavero, Ana Belén; Vigre, Håkan

    2015-01-01

    Consumption of poultry meat is considered as one of the main sources of human campylobacteriosis, and there is clearly a need for new surveillance and control measures based on quantitative data on Campylobacter spp. colonization dynamics in broiler chickens. We conducted four experimental...... infection trials, using four isolators during each infection trial to evaluate colonization of individual broiler chickens by Campylobacter jejuni over time. Individual and pooled faecal samples were obtained at days 4, 7 and 12 post-inoculation (p.i.) and caecal samples at day 12 p.i. There were large...

  19. Phenotypic characterisation of cell populations in the brains of horses experimentally infected with West Nile virus.

    Science.gov (United States)

    Delcambre, G H; Liu, J; Streit, W J; Shaw, G P J; Vallario, K; Herrington, J; Wenzlow, N; Barr, K L; Long, M T

    2017-11-01

    West Nile virus (WNV), a mosquito borne member of the Flaviviridae, is one of the most commonly diagnosed agents of viral encephalitis in horses and people worldwide. A cassette of markers for formalin-fixed paraffin-embedded tissue and an archive of tissues from experimental infections in the horse were used to investigate the equine neuroimmune response to WNV meningoencephalomyelitis to phenotype the early response to WNV infection in the horse. Quantitative analysis using archived tissue from experimentally infected horses. The thalamus and hindbrain from 2 groups of 6 horses were compared and consisted of a culture positive tissues from WNV experimentally horses, in the other, normal horses. Formalin-fixed paraffin-embedded tissue from the thalamus and hindbrain were immunolabeled for microglia, astrocytes, B cells, macrophages/neutrophils, CD3 + T cells. Fresh frozen tissues were immunolabeled for CD4 + and CD8 + T lymphocyte cell markers. Cell counts were obtained using a computer software program. Differences, after meeting assumptions of abnormality, were computed using a general linear model with a Tukey test (Phorses, Iba-1 + microglia, CD3 + T lymphocyte and MAC387 + macrophage staining were significantly increased. The T cell response for the WNV-challenged horses was mixed, composed of CD4 + and CD8 + T lymphocytes. A limited astrocyte response was also observed in WNV-challenged horses, and MAC387 + and B cells were the least abundant cell populations. The results of this study were limited by a single collection time post-infection. Furthermore, a comprehensive analysis of cellular phenotypes is needed for naturally infected horses. Unfortunately, in clinical horses, there is high variability of sampling in terms of days post-infection and tissue handling. The data show that WNV-challenged horses recruit a mixed T cell population at the onset of neurologic disease. © 2017 EVJ Ltd.

  20. Experimental infection of Leishmania (L. chagasi in a cell line derived from Lutzomyia longipalpis (Diptera:Psychodidae

    Directory of Open Access Journals (Sweden)

    Felio J Bello

    2005-10-01

    Full Text Available The present work describes the in vitro infection of a cell line Lulo, derived from Lutzomyia longipalpis embryonic tissue, by Leishmania chagasi promastigotes. This infection process is compared with a parallel one developed using the J774 cell line. The L. chagasi MH/CO/84/CI-044B strain was used for experimental infection in two cell lines. The cells were seeded on glass coverslips in 24-well plates to reach a final number of 2 x 10(5 cells/well. Parasites were added to the adhered Lulo and J774 cells in a 10:1 ratio and were incubated at 28 and 37ºC respectively. After 2, 4, 6, 8, and 10 days post-infection, the cells were extensively washed with PBS, fixed with methanol, and stained with Giemsa. The number of internalized parasites was determined by counting at least 400 cultured cells on each coverslip. The results showed continuous interaction between L. chagasi promastigotes with the cell lines. Some ultrastructural characteristics of the amastigote forms were observed using transmission electron microscopy. The highest percentage of infection in Lulo cells was registered on day 6 post-infection (29.6% and on day 4 in the J774 cells (51%. This work shows similarities and differences in the L. chagasi experimental infection process in the two cell lines. However, Lulo cells emerge as a new model to study the life-cycle of this parasite.

  1. Respiratory disease in ball pythons (Python regius) experimentally infected with ball python nidovirus.

    Science.gov (United States)

    Hoon-Hanks, Laura L; Layton, Marylee L; Ossiboff, Robert J; Parker, John S L; Dubovi, Edward J; Stenglein, Mark D

    2018-04-01

    Circumstantial evidence has linked a new group of nidoviruses with respiratory disease in pythons, lizards, and cattle. We conducted experimental infections in ball pythons (Python regius) to test the hypothesis that ball python nidovirus (BPNV) infection results in respiratory disease. Three ball pythons were inoculated orally and intratracheally with cell culture isolated BPNV and two were sham inoculated. Antemortem choanal, oroesophageal, and cloacal swabs and postmortem tissues of infected snakes were positive for viral RNA, protein, and infectious virus by qRT-PCR, immunohistochemistry, western blot and virus isolation. Clinical signs included oral mucosal reddening, abundant mucus secretions, open-mouthed breathing, and anorexia. Histologic lesions included chronic-active mucinous rhinitis, stomatitis, tracheitis, esophagitis and proliferative interstitial pneumonia. Control snakes remained negative and free of clinical signs throughout the experiment. Our findings establish a causal relationship between nidovirus infection and respiratory disease in ball pythons and shed light on disease progression and transmission. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  2. Impact of the post-weaning parasitism history on an experimental Haemonchus contortus infection in Creole goat kids.

    Science.gov (United States)

    Ceï, W; Mahieu, M; Philibert, L; Arquet, R; Alexandre, G; Mandonnet, N; Bambou, J C

    2015-01-15

    Gastrointestinal nematode (GIN) infections have an important negative impact on small ruminant production. The selection of genotypes resistant to these parasitic infections is a promising alternative control strategy. Thus, resistance against GIN is an important component of small ruminant breeding schemes, based on phenotypic measurements of resistance in immune mature infected animals. In this study we evaluated both the impact of the post-weaning parasitism history on the response to an experimental Haemonchus contortus infection of resistant and susceptible Creole kids chosen on the basis of their estimated breeding value, and the interaction with the kid's genetic status. During the post-weaning period (from 3 months until 7 months of age) Creole kids were reared at pasture according to four different levels of a mixed rotational stocking system with Creole cattle: 100% (control), 75% (GG75), 50% (GG50), and 25% (GG25) of the total stocking rate of the pasture. The level of infection of the kids decreased significantly at 50% and 25% of the total stocking rate. After the post-weaning period at pasture, at 11 months of age kids were experimentally infected with H. contortus. The faecal egg counts (FEC) were significantly lower in the groups showing the highest FEC at pasture. This result suggests that a degree of protection against an experimental H. contortus infection occurred during the post-weaning period and was dependant on the level of parasitism. Interestingly, no interaction was observed between this level of protection and the genetic status. In conclusion, the level of post-weaning natural parasitism history at pasture would not influence the genetic status evaluation. More generally our results suggest that it would be better to expose kids to a high level of gastrointestinal parasitism during the post-weaning period in order to increase the basal level of resistance thereafter. Copyright © 2014 Elsevier B.V. All rights reserved.

  3. Genomic and biological characterization of Newcastle disease viruses isolated from migratory mallards (Anas platyrhynchos).

    Science.gov (United States)

    Habib, Momena; Yaqub, Tahir; Nazir, Jawad; Shehzad, Wasim; Aziz-Ul-Rahman; Sohail, Tayyebah; Mukhtar, Nadia; Mehboob, Arsalan; Munir, Muhammad; Shabbir, Muhammad Zubair

    2018-04-30

    Given the global evolutionary dynamics of Newcastle disease viruses (NDVs), it is imperative to continue extensive surveillance, routine monitoring and characterization of isolates originating from natural reservoirs (waterfowls). In this report, we isolated and characterized two virulent NDV strains from clinically healthy mallard (Anas platyrhynchos). Both isolates had a genome of 15,192 nucleotides encoding six genes in an order of 3´-NP-P-M-F-HN-L-5´. The biological characteristics (mean death time: 49.5-50 hr, EID 50 10 8.5  ml -1 ) and presence of a typical cleavage site in the fusion (F) protein (112R-R-Q-K-R↓F117) confirmed the velogenic nature of these isolates. Phylogenetic analysis classified both isolates as members of genotype VII within class-II. Furthermore, based upon the hypervariable region of the F gene (375 nt), isolates showed clustering within sub-genotype VIIi. Similarity index and parallel comparison revealed a higher nucleotide divergence from commonly used vaccine strains; LaSota (21%) and Mukteswar (17%). A comparative residues analysis with representative strains of different genotypes, including vaccine strains, revealed a number of substitutions at important structural and functional domains within the F and hemagglutinin-neuraminidase (HN) proteins. Together, the results highlight consistent evolution among circulating NDVs supporting extensive surveillance of the virus in waterfowl to better elucidate epidemiology, evolutionary relationships and their impacts on commercial and backyard poultry.

  4. Isolation of Trichophyton mentogrophytes var mentogrophytes from naturally infected laboratory albino rats: experimental infection and treatment in rabbits

    Directory of Open Access Journals (Sweden)

    N. A. Issa

    2009-01-01

    Full Text Available The present study demonstrated for the first time the occurrence of dermatophytosis in naturally infected rats and from asymptomatic and from breeding boxes of white rats kept in animal housing of college of Veterinary Medicine, University of Dohuk, Iraq. The prevalence rate of infection was (28%, clinically infected rats characterized by appearance of scaly ovoid type lesions with crusty edge and patch of hair loss mostly seen on the back, neck and face of the infected rats, itching was reported in some rats. Only one species of the trichophyton, T. mentogrophytes var mentogrophytes was isolated with growth rate (85.71% of samples collected from clinically infected rats, and (28.57% from asymptomatic and from breeding cages, the growth was observed within the 21 days at 25ºC on Sabouraud's Dextrose Agar. Lacto phenol cotton blue staining slides of T. mentogrophytes var mentogrophytes revealed both microconidia and macroconidia. Microconidia found in numerous numbers often in dense cluster which were hyaline, smooth walled and predominantly spherical to sub spherical in shape, varying numbers of chlamydoconidia. Spiral hyphae and smooth, thin walled clavate shaped multicelled macroconidia were also present. The study also dealt with experimental infection in rabbits with T. mentogrophytes var mentogrophytes and treated by two drugs, natural herbal preparation of acidic pomegranate (Punica granatum fruit and synthetic nystatine ointment. The complete recovery of lesions was recorded after 14 days and 21 days of topical application of a pomegranate and nystatine ointment for 5 successive days respectively.

  5. Experimental infection of highly pathogenic avian influenza virus H5N1 in black-headed gulls (Chroicocephalus ridibundus)

    OpenAIRE

    Ramis , Antonio; van Amerongen , Geert; van de Bildt , Marco; Leijten , Loneke; Vanderstichel , Raphael; Osterhaus , Albert; Kuiken , Thijs

    2014-01-01

    Historically, highly pathogenic avian influenza viruses (HPAIV) rarely resulted in infection or clinical disease in wild birds. However, since 2002, disease and mortality from natural HPAIV H5N1 infection have been observed in wild birds including gulls. We performed an experimental HPAIV H5N1 infection of black-headed gulls (Chroicocephalus ridibundus) to determine their susceptibility to infection and disease from this virus, pattern of viral shedding, clinical signs, pathological changes a...

  6. Early weight development of goats experimentally infected with Mycobacterium avium subsp. paratuberculosis.

    Directory of Open Access Journals (Sweden)

    Alyssa N Malone

    Full Text Available Johne's disease is an infectious chronic inflammatory bowel disease in ruminants. The key factor for the management of this disease is an early positive diagnosis. Unfortunately, most diagnostics detect animals with Johne's disease in the clinical stage with positive serology and/or positive fecal cultures. However, for effective management of the disease within herds, it is important to detect infected animals as early as possible. This might only be possible with the help of parameters not specific for Johne's disease but that give an early indication for chronic infections such as weight development. Here we report our findings on the development of total body weight and weight gain during the first six months of goats experimentally infected to induce Johne's disease. Twenty dairy goat kids age 2 to 5 days were included in this study. Goats were divided into two groups: a negative control group and a positive infected group. The weight was obtained weekly throughout the study. Goats of the positive group were infected at the age of seven weeks. We detected significant changes in weight gain and total body weight as early as one week after infection. Differences are significant throughout the six month time period. Weight as a non-specific parameter should be used to monitor infection especially in studies on Johne's disease using the goat model. Our study suggests that goats with Johne's disease have a reduced weight gain and reduced weight when compared with healthy goats of the same age.

  7. Clinical presentation, convalescence, and relapse of rocky mountain spotted fever in dogs experimentally infected via tick bite.

    Directory of Open Access Journals (Sweden)

    Michael L Levin

    Full Text Available Rocky Mountain spotted fever (RMSF is a tick-borne disease caused by R. rickettsii in North and South America. Domestic dogs are susceptible to infection and canine RMSF can be fatal without appropriate treatment. Although clinical signs of R. rickettsii infection in dogs have been described, published reports usually include descriptions of either advanced clinical cases or experimental infections caused by needle-inoculation of cultured pathogen rather than by tick bite. The natural progression of a tick-borne R. rickettsii infection has not been studied in sufficient detail. Here, we provide a detailed description of clinical, hematological, molecular, and serological dynamics of RMSF in domestic dogs from the day of experimental exposure to infected ticks through recovery. Presented data indicate that neither the height/duration of fever nor detection of rickettsial DNA in dogs' blood by PCR are good indicators for clinical prognosis. Only the apex and subsequent subsidence of neutrophilia seem to mark the beginning of recovery and allow predicting a favorable outcome in Rickettsia-infected dogs, even despite the continuing persistence of mucosal petechiae and skin rash. On the other hand the appropriate (doxycycline antibiotic therapy of sufficient duration is crucial in prevention of RMSF relapses in dogs.

  8. Clinical presentation, convalescence, and relapse of rocky mountain spotted fever in dogs experimentally infected via tick bite.

    Science.gov (United States)

    Levin, Michael L; Killmaster, Lindsay F; Zemtsova, Galina E; Ritter, Jana M; Langham, Gregory

    2014-01-01

    Rocky Mountain spotted fever (RMSF) is a tick-borne disease caused by R. rickettsii in North and South America. Domestic dogs are susceptible to infection and canine RMSF can be fatal without appropriate treatment. Although clinical signs of R. rickettsii infection in dogs have been described, published reports usually include descriptions of either advanced clinical cases or experimental infections caused by needle-inoculation of cultured pathogen rather than by tick bite. The natural progression of a tick-borne R. rickettsii infection has not been studied in sufficient detail. Here, we provide a detailed description of clinical, hematological, molecular, and serological dynamics of RMSF in domestic dogs from the day of experimental exposure to infected ticks through recovery. Presented data indicate that neither the height/duration of fever nor detection of rickettsial DNA in dogs' blood by PCR are good indicators for clinical prognosis. Only the apex and subsequent subsidence of neutrophilia seem to mark the beginning of recovery and allow predicting a favorable outcome in Rickettsia-infected dogs, even despite the continuing persistence of mucosal petechiae and skin rash. On the other hand the appropriate (doxycycline) antibiotic therapy of sufficient duration is crucial in prevention of RMSF relapses in dogs.

  9. Experimental Infections of Oryzomys couesi with Sympatric Arboviruses from Mexico

    Science.gov (United States)

    Deardorff, Eleanor R.; Forrester, Naomi L.; Travassos da Rosa, Amelia P.; Estrada-Franco, Jose G.; Navarro-Lopez, Roberto; Tesh, Robert B.; Weaver, Scott C.

    2010-01-01

    Coues rice rat (Oryzomys couesi), a species abundant throughout Central America, was evaluated experimentally for the ability to serve as an amplifying host for three arboviruses: Patois (Bunyaviridae, Orthobunyavirus), Nepuyo (Orthobunyavirus), and Venezuelan equine encephalitis virus subtype ID (Togaviridae, Alphavirus). These three viruses have similar ecologies and are known to co-circulate in nature. Animals from all three cohorts survived infection and developed viremia with no apparent signs of illness and long-lasting antibodies. Thus, O. couesi may play a role in the general maintenance of these viruses in nature. PMID:20134016

  10. Immunodiagnosis of systemic aspergillosis. I. Antigenemia detected by radioimmunoassay in experimental infection

    International Nuclear Information System (INIS)

    Weiner, M.H.; Coats-Stephen, M.

    1979-01-01

    Because systemic aspergillosis is difficult to diagnose ante mortem, a study to improve immunodiagnosis was undertaken in a rabbit model of disseminated infection. We found that the predominant humoral response of infected animals was directed against four Aspergillus antigens identified by crossed immunoelectrophoresis. One of these antigens, a cell-wall carbohydrate, was purified by gel-filtration chromatography and was used to develop a radiommunoassay. The sensitivity of this assay was increased by testing for serum-bound antigen as well as for free antigen. When the sensitivity of the RIA was evaluated in the animal model, antigenemia was detected in 78% of 51 rabbits with disseminated infection and ante mortem in 86% of 42 rabbits with lethal infection. By contrast, with immunoprecipitin analysis only eight of 51 rabbits were positive for antigen, and six of 51 rabbits were positive for Aspergillus antibody. The specificity of the RIA was also tested. Negative controls for antigen included sera from 76 normal rabbits and sera from 25 rabbits with systemic candidiasis. The Candida control group is pertinent because 48% of these rabbits had specific Candida antigenemia detected by a mannan RIA. This study demonstrates that Aspergillus antigenemia occurs during the course of experimental disseminated aspergillosis and illustrates the potential of an Aspergillus antigen RIA for sensitive, specific immunodiagnosis of human infections

  11. Plasma thromboxane B2 levels in horses experimentally infected with Strongylus vulgaris.

    Science.gov (United States)

    Cambridge, H; Reynoldson, J A; Dunsmore, J D

    1989-06-01

    Plasma thromboxane B2 (TXB2) the stable inactive metabolite of thromboxane A2 (TXA2), was measured daily by specific radioimmunoassay in three groups of animals before and after experimental infection with Strongylus vulgaris. Infection of four 'parasite naive' foals produced a typical acute syndrome with intermittent but statistically insignificant rises in TXB2 levels. Interpretation of results was complicated by the presence of a non-septic peritonitis associated with implantation of the foals with electrodes for recording myoelectrical activity. In two foals of similar age, with some natural exposure to S. vulgaris, there was little or no clinical response to infection and increases in TXB2 were absent. Baseline levels were also much lower, indicating that the peritonitis may have affected the results obtained in the first group of foals. Severe mesenteric arteritis was confirmed at necropsy in all six foals. A third group of yearling horses, all with natural exposure to the parasite, were generally resistant to infection. One animal developed arteritis with clinical signs of diarrhoea and mild colic, and also showed intermittent increases in TXB2. The mean plasma TXB2 level after infection was significantly higher than in the control period, although absolute levels were lower than those recorded in the 'parasite naive' foals. Other animals in this group had low TXB2 levels and minimal arteritis was found at necropsy. These results indicate that although infection appears to have an effect on plasma TXB2, the changes are inconsistent and not reliable indicators of the presence of verminous arteritis. The results also confirm the difficulty in establishing infection and the variability of the response in animals with previous exposure.

  12. Experimental infection of highly pathogenic avian influenza virus H5N1 in black-headed gulls (Chroicocephalus ridibundus)

    NARCIS (Netherlands)

    A. Ramis (Antonio); G. van Amerongen (Geert); M.W.G. van de Bildt (Marco); L.M.E. Leijten (Lonneke); R. Vanderstichel (R.); A.D.M.E. Osterhaus (Albert); T. Kuiken (Thijs)

    2014-01-01

    textabstractHistorically, highly pathogenic avian influenza viruses (HPAIV) rarely resulted in infection or clinical disease in wild birds. However, since 2002, disease and mortality from natural HPAIV H5N1 infection have been observed in wild birds including gulls. We performed an experimental

  13. [Experimental model of activated Lamblia (Giardia) muris infection in albino mice].

    Science.gov (United States)

    Irikov, O A; Kovalenko, F P

    2007-01-01

    Experimental L. muris infection was reproduced in 100% of the intact albino mice intragastrically given levomycin in an average total dose of 15.88-34.84 or 0.88-1.02 g/kg for 18-34 days. With levomycin administration, the intensity of giardiasis was 1121.6-8540.1 (mean 4830.9) thousand L. muris trophozoites per animal. The total number of trophozoites per animal decreased to 302.2-3481.4 (mean 1546.4) thousand and 28.1-324.0 (mean 109.4) thousand specimens 5-8 and 11-13 days after discontinuation of the antibiotic, respectively. The maximum number of L. muris trophozoites was observed in the proximal and middle portions of the murine small intestine during and after the administration oflevomycin. The highest isolation of cysts was seen 12-14 days after the initiation of administration of the antibiotic. Following 8-10 days of terminations of a course of levomycin therapy the native smear of animal feces showed no Lamblia cysts. In mice with activated infection, the isolation rate of Lamblia cysts was directly related to the intensity of intestinal infection with trophozoites of the parasite.

  14. Quasi-experimental Studies in the Fields of Infection Control and Antibiotic Resistance, Ten Years Later: A Systematic Review.

    Science.gov (United States)

    Alsaggaf, Rotana; O'Hara, Lyndsay M; Stafford, Kristen A; Leekha, Surbhi; Harris, Anthony D

    2018-02-01

    OBJECTIVE A systematic review of quasi-experimental studies in the field of infectious diseases was published in 2005. The aim of this study was to assess improvements in the design and reporting of quasi-experiments 10 years after the initial review. We also aimed to report the statistical methods used to analyze quasi-experimental data. DESIGN Systematic review of articles published from January 1, 2013, to December 31, 2014, in 4 major infectious disease journals. METHODS Quasi-experimental studies focused on infection control and antibiotic resistance were identified and classified based on 4 criteria: (1) type of quasi-experimental design used, (2) justification of the use of the design, (3) use of correct nomenclature to describe the design, and (4) statistical methods used. RESULTS Of 2,600 articles, 173 (7%) featured a quasi-experimental design, compared to 73 of 2,320 articles (3%) in the previous review (Pquasi-experimental design; and 68 (39%) identified their design using the correct nomenclature. In addition, 2-group statistical tests were used in 75 studies (43%); 58 studies (34%) used standard regression analysis; 18 (10%) used segmented regression analysis; 7 (4%) used standard time-series analysis; 5 (3%) used segmented time-series analysis; and 10 (6%) did not utilize statistical methods for comparisons. CONCLUSIONS While some progress occurred over the decade, it is crucial to continue improving the design and reporting of quasi-experimental studies in the fields of infection control and antibiotic resistance to better evaluate the effectiveness of important interventions. Infect Control Hosp Epidemiol 2018;39:170-176.

  15. E-NTPDase and E-ADA activities in rats experimental infected by Cryptococcus neoformans.

    Science.gov (United States)

    de Azevedo, Maria Isabel; Ferreiro, Laerte; Da Silva, Aleksandro S; Tonin, Alexandre A; Ruchel, Jader B; Rezer, João F P; França, Raqueli T; Zimmermann, Carine E P; Leal, Daniela B R; Duarte, Marta M M F; Lopes, Sonia T A; Flores, Mariana M; Fighera, Rafael; Santurio, Janio M

    2014-11-07

    Cryptococcus neoformans, the etiological agent of cryptococcosis, is an opportunistic fungal pathogen of immunocompromised individuals. The aim of this study was to evaluate the activities of E-NTPDase and E-ADA in rats experimentally infected by C. neoformans var. grubii. Adult rats (35) were divided in two groups: 18 for the control group (uninfected) (A), and 17 for the infected group (B). Each group was separated into three sub-groups (A1, A2, A3-B1, B2, B3), and samples were collected on 10, 20, and 30 days post-infection (PI). Leukocyte counts, IFN-γ, TNF-α, IgM, IgG levels, and E-NTPDase and E-ADA activities were analyzed. It was possible to observe that IgG and IgM seric levels of infected rats were significantly elevated (PADA activity had a significant reduction (PADA activity in lymphocytes increased significantly (PADA), concomitantly with an inflammatory response (increased levels of cytokines and immunoglobulins) associated with inflammatory infiltrates and histological lesions in the lung. Copyright © 2014 Elsevier B.V. All rights reserved.

  16. Ultrastructural identification of Ehrlich ia sp in an experimentally infected dog in Venezuela

    International Nuclear Information System (INIS)

    Gutierrez, N.; Martinez, M.; Arraga Alvarado, C.; Bretana, A.; Pacheco, I.; Comach, G.

    1999-01-01

    This study is the first report made in Venezuela concerning the ultrastructural characteristics of Ehrlich ia sp in mononuclear blood cells from an experimentally infected dog. The animal developed clinical manifestations characteristic of the infection, and typical intracytoplasmic inclusion bodies were clearly seen in blood smears stained with modified Giemsa examined by light microscopy. Microorganisms were visualized by transmission electron microscopy. The cytoplasmic inclusions, consisted of membrane-lined vacuole-containing elementary bodies. The organisms were extremely pleomorphic. Elementary bodies were surrounded by two distinct membranes and each was constituted by electro-dense granules. These findings corresponded to the described electron microscopy morphology which characterizes the Ehrlich ia genus

  17. Experimental infections with Mycoplasma agalactiae identify key factors involved in host-colonization.

    Directory of Open Access Journals (Sweden)

    Eric Baranowski

    Full Text Available Mechanisms underlying pathogenic processes in mycoplasma infections are poorly understood, mainly because of limited sequence similarities with classical, bacterial virulence factors. Recently, large-scale transposon mutagenesis in the ruminant pathogen Mycoplasma agalactiae identified the NIF locus, including nifS and nifU, as essential for mycoplasma growth in cell culture, while dispensable in axenic media. To evaluate the importance of this locus in vivo, the infectivity of two knock-out mutants was tested upon experimental infection in the natural host. In this model, the parental PG2 strain was able to establish a systemic infection in lactating ewes, colonizing various body sites such as lymph nodes and the mammary gland, even when inoculated at low doses. In these PG2-infected ewes, we observed over the course of infection (i the development of a specific antibody response and (ii dynamic changes in expression of M. agalactiae surface variable proteins (Vpma, with multiple Vpma profiles co-existing in the same animal. In contrast and despite a sensitive model, none of the knock-out mutants were able to survive and colonize the host. The extreme avirulent phenotype of the two mutants was further supported by the absence of an IgG response in inoculated animals. The exact role of the NIF locus remains to be elucidated but these data demonstrate that it plays a key role in the infectious process of M. agalactiae and most likely of other pathogenic mycoplasma species as many carry closely related homologs.

  18. Comparison of abortion and infection after experimental challenge of pregnant bison and cattle with Brucella abortus strain 2308

    Science.gov (United States)

    A comparative study was conducted using data from naive bison (n=45) and cattle (n=46) from 8 and 6 studies, respectively, in which a standardized Brucella abortus strain 2308 experimental challenge was administered. The incidence of abortion, fetal infection, uterine or mammary infection, or infec...

  19. Cross-Species Infectivity of H3N8 Influenza Virus in an Experimental Infection in Swine.

    Science.gov (United States)

    Solórzano, Alicia; Foni, Emanuela; Córdoba, Lorena; Baratelli, Massimiliano; Razzuoli, Elisabetta; Bilato, Dania; Martín del Burgo, María Ángeles; Perlin, David S; Martínez, Jorge; Martínez-Orellana, Pamela; Fraile, Lorenzo; Chiapponi, Chiara; Amadori, Massimo; del Real, Gustavo; Montoya, María

    2015-11-01

    Avian influenza A viruses have gained increasing attention due to their ability to cross the species barrier and cause severe disease in humans and other mammal species as pigs. H3 and particularly H3N8 viruses, are highly adaptive since they are found in multiple avian and mammal hosts. H3N8 viruses have not been isolated yet from humans; however, a recent report showed that equine influenza A viruses (IAVs) can be isolated from pigs, although an established infection has not been observed thus far in this host. To gain insight into the possibility of H3N8 avian IAVs to cross the species barrier into pigs, in vitro experiments and an experimental infection in pigs with four H3N8 viruses from different origins (equine, canine, avian, and seal) were performed. As a positive control, an H3N2 swine influenza virus A was used. Although equine and canine viruses hardly replicated in the respiratory systems of pigs, avian and seal viruses replicated substantially and caused detectable lesions in inoculated pigs without previous adaptation. Interestingly, antibodies against hemagglutinin could not be detected after infection by hemagglutination inhibition (HAI) test with avian and seal viruses. This phenomenon was observed not only in pigs but also in mice immunized with the same virus strains. Our data indicated that H3N8 IAVs from wild aquatic birds have the potential to cross the species barrier and establish successful infections in pigs that might spread unnoticed using the HAI test as diagnostic tool. Although natural infection of humans with an avian H3N8 influenza A virus has not yet been reported, this influenza A virus subtype has already crossed the species barrier. Therefore, we have examined the potential of H3N8 from canine, equine, avian, and seal origin to productively infect pigs. Our results demonstrated that avian and seal viruses replicated substantially and caused detectable lesions in inoculated pigs without previous adaptation. Surprisingly, we

  20. [INTESTINAL FAILURE AND YERSINIA PSEUDOTUBERCULOSIS TRANSLOCATION IN THE DEVELOPMENTOF EXPERIMENTAL GENERALIZED INFECTION].

    Science.gov (United States)

    Chicherin, I Yu; Pogorelky, I P; Lundovskikh, I A; Darmov, I V; Gorshkov, A S; Shabalina, M R

    2016-01-01

    To determine the value of intestinal failure and translocation of bacteria Y. pseudotuberculosis, and normal intestinal microbiota in the initiation and generalization of infection in experimental pseudotuberculosis in conventional white mice, as well as pathological manifestation of it as a response to the adhesion and colonization of the mucosus membrane by pathogenic bacteria Y. pseudotuberculosis. Experimental models of pseudotuberculosis in conventional white mice used the pathogenic Y. pseudotuberculosis 147 serotype I strain, containing a calcium-dependence plasmid with a molecular weight of 47 MDa. Cultivation of the pseudotuberculosis pathogen given its psychrophilic was performed on Hottinger agar at a temperature of (4-5) °C. The lactobacilli strain L plantarum 8P-A3 was isolated from a lyophilized commercial probiotic Lactobacterin (manufactured by "NPO Microgen", Russia) and used to obtain native culture supernatant fluid of lactobacilli, the composition of which was detected by gas-liquid chromatography with mass-selective detection. Gentamicin for parenteral administration was manufactured by JSC "Biochemist", Russia. Pathomorphological examination was performed on the 4-6th day of the experiment. Fragments of the small intestine, liver, kidneys, and lungs from dead animals were chosen for examination. Tissues were fixed in 10% neutral formalin, dehydrated in isopropanol and embedded in paraffin. Preparations were stained with Ehrlich hematoxylin and eosin, examined on the microscope "Mikmed-2" (JSC "LOMO", Russia) under magnification x 200-x1000. Statistical processing of the experimental results was carried out according to the method of Kerber in modification of I.P. Ashmarin and A.A. Vorobyov. The role of intestinal failure and translocation of bacteria Y. pseudotuberculosis, and normal intestinal microbiota in the initiation and generalization of infection in animals has been found. It has been proved that the oral administration of supernatant

  1. Intra-uterine experimental infection by Ureaplasma diversum induces TNF-α mediated womb inflammation in mice

    Directory of Open Access Journals (Sweden)

    Jamile R. Silva

    2016-01-01

    Full Text Available Ureaplasma diversum is an opportunistic pathogen associated with uterine inflammation, impaired embryo implantation, infertility, abortions, premature birth of calves and neonatal pneumonia in cattle. It has been suggested that the intra-uterine infection by Ureaplasma diversum can cause vascular changes that hinder the success of pregnancy. Thus, the aim of this study was to evaluate the changes of intrauterine site of A/J mice in estrus or proestrus phase inoculated with Ureaplasma diversum. The infection was monitored at 24, 48 and 72 hours by the PCR methodology to detect the Ureaplasma in the inoculation site and the profile of circulating blood cells. Morphological changes, intensity of inflammation and the production of cytokines were compared. The infected mice showed local inflammation through the production of IFN-γ and TNF-α. Ureaplasma diversum infections in the reproductive tract of studied mice seemed to be associated with the production of pro-inflammatory cytokines in uterine parenchyma. The levels of TNF-α of infected mice were dependent on the bacterial load of inoculated Ureaplasma. Uterine experimental infections by Ureaplasma diversum have not been mentioned yet and herein we presented the first report of an intrauterine infection model in mice.

  2. Intra-uterine experimental infection by Ureaplasma diversum induces TNF-α mediated womb inflammation in mice.

    Science.gov (United States)

    Silva, Jamile R; Ferreira, Lício F A A; Oliveira, Percíllia V S; Nunes, Ivanéia V; Pereira, Ítalo S; Timenetsky, Jorge; Marques, Lucas M; Figueiredo, Tiana B; Silva, Robson A A

    2016-01-01

    Ureaplasma diversum is an opportunistic pathogen associated with uterine inflammation, impaired embryo implantation, infertility, abortions, premature birth of calves and neonatal pneumonia in cattle. It has been suggested that the intra-uterine infection by Ureaplasma diversum can cause vascular changes that hinder the success of pregnancy. Thus, the aim of this study was to evaluate the changes of intrauterine site of A/J mice in estrus or proestrus phase inoculated with Ureaplasma diversum. The infection was monitored at 24, 48 and 72 hours by the PCR methodology to detect the Ureaplasma in the inoculation site and the profile of circulating blood cells. Morphological changes, intensity of inflammation and the production of cytokines were compared. The infected mice showed local inflammation through the production of IFN-γ and TNF-α. Ureaplasma diversum infections in the reproductive tract of studied mice seemed to be associated with the production of pro-inflammatory cytokines in uterine parenchyma. The levels of TNF-α of infected mice were dependent on the bacterial load of inoculated Ureaplasma. Uterine experimental infections by Ureaplasma diversum have not been mentioned yet and herein we presented the first report of an intrauterine infection model in mice.

  3. Levels of metals in blood samples from Mallards (Anas platyrhynchos) from urban areas in Poland

    International Nuclear Information System (INIS)

    Binkowski, Łukasz J.; Meissner, Włodzimierz

    2013-01-01

    In this paper we present the studies conducted on blood samples taken from Mallards (Anas platyrhynchos). Birds were captured for ringing purposes (n = 43) in two small and two big towns (including highly urbanized areas). For comparison samples of blood from birds shot on fish ponds were used (n = 26). Based on the body mass all sampled individuals can be assessed as being in good condition. Levels of cadmium (Cd), chromium (Cr), copper (Cu), iron (Fe), nickel (Ni), lead (Pb) and zinc (Zn) in blood samples were measured with AAS. Concentrations of metals did not differ statistically between sexes and made up a following order: Fe > Zn > Cu > Cr ≈ Ni > Pb > Cd. Mallards from towns revealed lower concentrations of Zn and Cu but higher concentration of Fe. There was no difference in exposition to Pb between birds from towns and fish ponds. -- Highlights: •Concentrations of seven metals were measured in blood of Mallards. •Birds represent different kind of areas: urban (towns) and non-urban ones (fish ponds). •Concentrations of studied metals made up a following order: Fe > Zn > Cu > Cr ≈ Ni > Pb > Cd. •Birds from towns revealed higher amount of Fe and lower concentrations of Zn and Cu. •There was no difference in exposition to Pb between birds from towns and fish ponds. -- Exposition to iron is higher on industrialized areas in towns, but exposition to zinc and copper on such areas is lower in comparison to country fish ponds

  4. Metabolomic profiling of faecal extracts from Cryptosporidium parvum infection in experimental mouse models.

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    Josephine S Y Ng Hublin

    Full Text Available Cryptosporidiosis is a gastrointestinal disease in humans and animals caused by infection with the protozoan parasite Cryptosporidium. In healthy individuals, the disease manifests mainly as acute self-limiting diarrhoea, but may be chronic and life threatening for those with compromised immune systems. Control and treatment of the disease is challenged by the lack of sensitive diagnostic tools and broad-spectrum chemotherapy. Metabolomics, or metabolite profiling, is an emerging field of study, which enables characterisation of the end products of regulatory processes in a biological system. Analysis of changes in metabolite patterns reflects changes in biochemical regulation, production and control, and may contribute to understanding the effects of Cryptosporidium infection in the host environment. In the present study, metabolomic analysis of faecal samples from experimentally infected mice was carried out to assess metabolite profiles pertaining to the infection. Gas-chromatography mass spectrometry (GC-MS carried out on faecal samples from a group of C. parvum infected mice and a group of uninfected control mice detected a mean total of 220 compounds. Multivariate analyses showed distinct differences between the profiles of C. parvum infected mice and uninfected control mice,identifying a total of 40 compounds, or metabolites that contributed most to the variance between the two groups. These metabolites consisted of amino acids (n = 17, carbohydrates (n = 8, lipids (n = 7, organic acids (n = 3 and other various metabolites (n = 5, which showed significant differences in levels of metabolite abundance between the infected and uninfected mice groups (p < 0.05. The metabolites detected in this study as well as the differences in abundance between the C. parvum infected and the uninfected control mice, highlights the effects of the infection on intestinal permeability and the fate of the metabolites as a result of nutrient scavenging by the

  5. Experimental infection of duck origin virulent Newcastle disease virus strain in ducks.

    Science.gov (United States)

    Dai, Yabin; Cheng, Xu; Liu, Mei; Shen, Xinyue; Li, Jianmei; Yu, Shengqing; Zou, Jianmin; Ding, Chan

    2014-07-17

    Newcastle disease (ND) caused by virulent Newcastle disease virus (NDV) is an acute, highly contagious and fatal viral disease affecting most species of birds. Ducks are generally considered to be natural reservoirs or carriers of NDV while being resistant to NDV strains, even those most virulent for chickens; however, natural ND cases in ducks have been gradually increasing in recent years. In the present study, ducks of different breeds and ages were experimentally infected with duck origin virulent NDV strain duck/Jiangsu/JSD0812/2008 (JSD0812) by various routes to investigate the pathogenicity of NDV in ducks. Six breeds (mallard, Gaoyou, Shaoxing, Jinding, Shanma, and Pekin ducks) were infected intramuscularly (IM) with JSD0812 strain at the dose of 5 × 108 ELD50. Susceptibility to NDV infection among breeds varied, per morbidity and mortality. Mallard ducks were the most susceptible, and Pekin ducks the most resistant. Fifteen-, 30-, 45-, 60-, and 110-day-old Gaoyou ducks were infected with JSD0812 strain at the dose of 5 × 108 ELD50 either IM or intranasally (IN) and intraocularly (IO), and their disease development, viral shedding, and virus tissue distribution were determined. The susceptibility of ducks to NDV infection decreased with age. Most deaths occurred in 15- and 30-day-old ducklings infected IM. Ducks infected IN and IO sometimes exhibited clinical signs, but seldom died. Clinical signs were primarily neurologic. Infected ducks could excrete infectious virus from the pharynx and/or cloaca for a short period, which varied with bird age or inoculation route; the longest period was about 7 days. The rate of virus isolation in tissues from infected ducks was generally low, even in those from dead birds, and it appeared to be unrelated to bird age and infection route. The results confirmed that some of the naturally occurring NDV virulent strains can cause the disease in ducks, and that ducks play an important role in the epidemiology of ND. The

  6. Infectivity of DWV associated to flower pollen: experimental evidence of a horizontal transmission route.

    Directory of Open Access Journals (Sweden)

    Maurizio Mazzei

    Full Text Available Deformed wing virus (DWV is a honeybee pathogen whose presence is generally associated with infestation of the colony by the mite Varroa destructor, leading to the onset of infections responsible for the collapse of the bee colony. DWV contaminates bee products such as royal jelly, bee-bread and honey stored within the infected hive. Outside the hive, DWV has been found in pollen loads collected directly from infected as well as uninfected forager bees. It has been shown that the introduction of virus-contaminated pollen into a DWV-free hive results in the production of virus-contaminated food, whose role in the development of infected bees from virus-free eggs has been experimentally demonstrated. The aim of this study was twofold: (i to ascertain the presence of DWV on pollen collected directly from flowers visited by honeybees and then quantify the viral load and (ii determine whether the virus associated with pollen is infective. The results of our investigation provide evidence that DWV is present on pollen sampled directly from visited flowers and that, following injection in individuals belonging to the pollinator species Apis mellifera, it is able to establish an active infection, as indicated by the presence of replicating virus in the head of the injected bees. We also provide the first indication that the pollinator species Osmia cornuta is susceptible to DWV infection.

  7. Testing the sensitivity of Nested PCR method to detect Aspergillus fumigates in experimentally infected Sputum samples

    International Nuclear Information System (INIS)

    Ramadan, A.; Soukkaria, S.

    2013-01-01

    Fungal infections caused by Aspergillus species generally are occupying a second place among invasive fungal infections in the world, especially A. fumigatus, which is considered the main cause of invasive Aspergillosis (IA). Although IA rarely infects immunocompetent individuals, however, it can lead to death in immunocompromised patients. Therefore, it is necessary to diagnose the infection early in order to treat the disease efficiently. However, the conventional diagnostic tools, currently used to detect infections, has low sensitivity and reliability. Polymerase chain reaction (PCR) technology distribution as a molecular and high sensitive technology has allowed us to make comparative study between sensitivity of traditional currently used diagnostic method and Nested-PCR, the result of the study of sputum samples that experimentally infected with different concentrations of A.fumigatus spores ramping from 10 to10 6 spore/ml, have high sensitivity and specificity of Nested-PCR in detecting the lower concentrations, comparing with traditional diagnostic method (culture on Sabouraud media) that were negative in all concetrations. (author)

  8. Studies on vertical transmission of Trichinella spiralis in experimentally infected guinea pigs (Cavia porcellus).

    Science.gov (United States)

    Riva, Eliana; Fiel, Cesar; Bernat, Gisele; Muchiut, Sebastián; Steffan, Pedro

    2017-08-01

    An experimental study to enhance knowledge on the capability of Trichenella spiralis to pass from guinea pigs to progeny at different periods of pregnancy or lactation was performed. For this purpose, 18 female adult guinea pigs were inoculated with 100 or 1000 T. spiralis muscle larvae (ML) during early, late gestation and during lactation period. The presence of T. spiralis (ML) in mothers and newborns was studied through enzymatic digestion from muscle samples. ML were observed in 9 of 42 newborn guinea pigs and levels of infection were significantly higher when infections of mothers were done during late gestation (p = 0.0046) with the high infective dose (p = 0.0043). T. spiralis ML were not recovered from any of the newborns from mothers infected in the lactation period. Ten out of 18 infected mothers presented larvae 1 in their mammary glands. Muscle samples from the tongue and the masseter showed the highest larval burdens. These observations confirm previous reports on that ML of T. spiralis are capable to pass through placental tissues to reach and encyst in striated muscle groups of newborn guinea pigs. This study may also reinforce the importance of preventive programs to control trichinellosis in those endemic areas where pregnant women would have high risk of infection.

  9. Pathology, clinical signs, and tissue distribution of Toxoplasma gondii in experimentally infected reindeer (Rangifer tarandus

    Directory of Open Access Journals (Sweden)

    Émilie Bouchard

    2017-12-01

    Full Text Available Toxoplasma gondii is a zoonotic parasite found in vertebrates worldwide for which felids serve as definitive hosts. Despite low densities of felids in northern Canada, Inuit people in some regions show unexpectedly high levels of exposure, possibly through handling and consumption of Arctic wildlife. Free-ranging caribou (Rangifer tarandus are widely harvested for food across the Canadian North, show evidence of seroexposure to T. gondii, and are currently declining in numbers throughout the Arctic. We experimentally infected three captive reindeer (conspecific with caribou with 1000, 5000 or 10,000 oocysts of T. gondii via stomach intubation to assess clinical signs of infection, pathology, and tissue distribution. An unexposed reindeer served as a negative control. Signs of stress, aggression, and depression were noted for the first two weeks following infection. By 4 weeks post infection, all infected reindeer were positive on a modified agglutination test at the highest titer tested (1:200 for antibodies to T. gondii. At 20 weeks post infection, no gross abnormalities were observed on necropsy. Following histopathology and immunohistochemistry, tissue cysts were visualized in the reindeer given the highest and lowest dose of oocysts. Focal pleuritis and alveolitis were associated with respiratory problems in reindeer given the middle dose. DNA of T. gondii was detected following traditional DNA extraction and conventional PCR on 25 mg samples from 17/33 muscles and organs, and by magnetic capture DNA extraction from 100 g samples from all 26 tissues examined. This research demonstrated that reindeer/caribou can serve as intermediate hosts for T. gondii, and that the parasite may be associated with health effects in wildlife. The presence of T. gondii in all tissues tested, many of which are commonly consumed raw, smoked, or dried in northern communities, suggests that caribou may serve as a source of human exposure to T

  10. Immunohistochemical detection of Tritrichomonas foetus in experimentally infected mice

    Directory of Open Access Journals (Sweden)

    Monteavaro Cristina Esther

    2000-01-01

    Full Text Available The need to intensify knowledge of the pathogenesis of bovine genital trichomoniasis (BGT led to the use of alternative animal models such as the mouse. Nevertheless, it is necessary to elucidate the dynamics of the infection in this animal species, evaluating different stages of the colonization and evolution of the pathological alterations. The immunohistochemistry (IHC offers advantages over the routine histopathological staining techniques for the detection of the protozoan in tissues, cellular detritus and inside the macrophages. The goal of the present study was to demonstrate the presence of Tritrichomonas foetus in the reproductive tract of infected mice using an IHC technique. Female BALB/c mice were infected with a suspension of T. foetus by intravaginal route, in the estrum phase, detected by exfoliative vaginal cytology. After 10 weeks, the animals were sacrificed; uterus and vagina were fixed and histologically processed. Some slides were stained with HE. The rest of the slides were processed for IHC. An immunoadsorbed polyclonal serum against T. foetus was used. The avidine-biotine technique (HistoMouse, Zymed[tm] was employed. The histopathological studies showed a dilation of the uterine glands, presence of macrophages in the lumen of the organ and inner part of the endometrial glands. No T. foetus was identified using this method. The IHQ allowed additionally the identification of the protozoan in the endometrium, endometrial glands, uterine lumen and inside neutrophils and macrophages. The cytological studies stained with IHC showed either isolated T. foetus adhered to epithelial cells or inside macrophages. This technique proves to be a useful tool for the study of the pathogenesis of bovine genital trichomoniasis (BGT in an experimental model.

  11. Experimentally induced intravaginal Tritrichomonas foetus infection in a mouse model Infecção experimental intravaginal com Tritricho-monas foetus em modelo camundongo

    Directory of Open Access Journals (Sweden)

    Pedro Soto

    2005-12-01

    Full Text Available The interest to develop research on the host-parasite relationship in bovine tritrichomonosis has accomplished the use of experimental models alternative to cattle. The BALB/c mouse became the most appropriate species susceptible to vaginal Tritrichomonas foetus infection requiring previous estrogenization. For the need of an experimental model without persistent estrogenization and with normal estrous cycles, the establishment and persistence of vaginal infection on BALB/c mouse with different concentrations of T. foetus in two experimental groups was evaluated. Group A was treated with 5mg of b-estradiol 3-benzoate to synchronize the estrous, 48 hours before the T. foetus vaginal inoculation, and Group B was inoculated in natural estrus. At 5-7 days after treatment, estrogenic effect decreased allowing all animals to cycle regularly during the experiment. From the first week post-infection, samples of vaginal mucus were taken from all animals during 34 weeks, in order to evaluate the course of infection and the stage of the estrus cycle. Group A showed 93.6% of infected animals, and Group B showed 38%. Different doses of T. foetus were assayed to establish the vaginal infection, with a persistence of 34 weeks. Although different behavior was observed in each subgroup belonging to either Group A or Group B, there were no significant differences among the infecting doses used. The b-estradiol 3-benzoate treatment had a favorable effect on the establishment of the infection (PA necessidade de esclarecer a relação agente-hospedeiro na tricomoníase bovina deu motivo para o uso de modelos experimentais alternativos ao bovino. O camundongo BALB/c resultou como espécie mais adequada para a infeção vaginal com Tritrichomonas foetus, requerendo uma estrogenização prévia. Visando a necessidade de um modelo experimental sem estrogenização persistente e com ciclos estrais normais, foi avaliada a instalação e persistência da infeção vaginal

  12. Experimental infection of pigs with two East European variants of Type 1 PRRSV

    DEFF Research Database (Denmark)

    Hjulsager, Charlotte Kristiane; Larsen, Lars Erik; Heegaard, Peter M. H.

    Porcine reproductive and respiratory syndrome viruses (PRRSV) have been divided into Type 1 (European) and Type 2 (North American) viruses. PRRSV are very diverse and Type 1 viruses have even been further divided into subtypes. While Type 1 viruses from Western Europe belong to subtype 1, viruses...... the subtype 1 strains. The aim of this project was to study the infection dynamics and clinical and pathological impact of two east European Type 1 strains. In an experimental trial, infection of pigs with the Russian subtype 2 strain “Ili6” and the Belarusian atypical isolate “Bor59” were compared...... to an early “Lelystad-like” Danish subtype 1 isolate “18794”. Groups of seven pigs of unique high sanitary status were infected with one of the three PRRSV isolates, and a fourth group served as sham-inoculated controls. The pigs were monitored for 24 days, and nasal swabs and blood samples were taken at 0, 3...

  13. An investigation on vertical transmission of Leishmania infantum in experimentally infected dogs and assessment of offspring's infectiousness potential by xenodiagnosis.

    Science.gov (United States)

    Ben Slimane, T; Chouihi, E; Ben Hadj Ahmed, S; Chelbi, I; Barhoumi, W; Cherni, S; Zoghlami, Z; Gharbi, M; Zhioua, E

    2014-12-15

    Dogs are the main reservoir host of Leishmania infantum, etiologic agent of human visceral leishmaniasis (HVL) and canine visceral leishmaniasis (CVL). Transmission of L. infantum to humans and dogs is mainly through the bite of infected sand flies. In the Western Mediterranean basin, Phlebotomus perniciosus is the main vector of L. infantum. However, occasional vertical transmission of L. infantum has been reported. This study investigated L. infantum vertical transmission in offspring of experimentally infected dogs. Among 14 surviving puppies from three female beagle dogs that developed CVL following an experimental infection with L. infantum, one was tested positive by indirect immunofluorescence antibody test, by PCR and by xenodiagnosis with a high parasite burden in the spleen at 14 months old. None of the remaining puppies were tested positive for L. infantum. These findings strongly suggest that infected puppies following vertical transmission can sustain infection and contribute in infecting sand flies with L. infantum. Any strategy for controlling CVL should take into consideration the vertical transmission of L. infantum. Copyright © 2014 Elsevier B.V. All rights reserved.

  14. Experimental infection of Marmota monax with a novel hepatitis A virus.

    Science.gov (United States)

    Yu, Jie-Mei; Li, Li-Li; Xie, Guang-Cheng; Zhang, Cui-Yuan; Ao, Yuan-Yun; Duan, Zhao-Jun

    2018-05-01

    To establish an animal model for the newly identified Marmota Himalayana hepatovirus, MHHAV, so as to develop a better understanding of the infection of hepatitis A viruses. Five experimental woodchucks (Marmota monax) were inoculated intravenously with the purified MHHAV from wild woodchuck feces. One animal injected with PBS was defined as a control. Feces and blood were routinely collected. After the animals were subjected to necropsy, different tissues were collected. The presence of viral RNA and negative sense viral RNA was analyzed in all the samples and histopathological and in situ hybridization analysis was performed for the tissues. MHHAV infection caused fever but no severe symptoms or death. Virus was shed in feces beginning at 2 dpi, and MHHAV RNA persisted in feces for ~2 months, with a biphasic increase, and in blood for ~30 days. Viral RNA was detected in all the tissues, with high levels in the liver and spleen. Negative-strand viral RNA was detected only in the liver. Furthermore, the animals showed histological signs of hepatitis at 45 dpi. MHHAV can infect M. monax and is associated with hepatic disease. Therefore, this animal can be used as a model of HAV pathogenesis and to evaluate antiviral and anticancer therapeutics.

  15. Aeromonas caviae inhibits hepatic enzymes of the phosphotransfer network in experimentally infected silver catfish: Impairment on bioenergetics.

    Science.gov (United States)

    Baldissera, M D; Souza, C F; Verdi, C M; Dos Santos, K L M; Da Veiga, M L; da Rocha, M I U M; Santos, R C V; Vizzotto, B S; Baldisserotto, B

    2018-03-01

    Several studies have been demonstrated that phosphotransfer network, through the adenylate kinase (AK) and pyruvate kinase (PK) activities, allows for new perspectives leading to understanding of disease conditions associated with disturbances in energy metabolism, metabolic monitoring and signalling. In this sense, the aim of this study was to evaluate whether experimental infection by Aeromonas caviae alters hepatic AK and PK activities of silver catfish Rhamdia quelen. Hepatic AK and PK activities decreased in infected animals compared to uninfected animals, as well as the hepatic adenosine triphosphate (ATP) levels. Also, a severe hepatic damage was observed in the infected animals due to the presence of dilation and congestion of vessels, degeneration of hepatocytes and loss of liver parenchyma architecture and sinusoidal structure. Therefore, we have demonstrated, for the first time, that experimental infection by A. caviae inhibits key enzymes linked to the communication between sites of ATP generation and ATP utilization. Moreover, the absence of a reciprocal compensatory mechanism between these enzymes contributes directly to hepatic damage and for a severe energetic imbalance, which may contribute to disease pathophysiology. © 2017 John Wiley & Sons Ltd.

  16. Fibrinogen and fibronectin binding cooperate for valve infection and invasion in Staphylococcus aureus experimental endocarditis

    NARCIS (Netherlands)

    Que, Yok-Ai; Haefliger, Jacques-Antoine; Piroth, Lionel; François, Patrice; Widmer, Eleonora; Entenza, José M; Sinha, Bhanu; Herrmann, Mathias; Francioli, Patrick; Vaudaux, Pierre; Moreillon, Philippe

    2005-01-01

    The expression of Staphylococcus aureus adhesins in Lactococcus lactis identified clumping factor A (ClfA) and fibronectin-binding protein A (FnBPA) as critical for valve colonization in rats with experimental endocarditis. This study further analyzed their role in disease evolution. Infected

  17. Experimental Maedi Visna Virus Infection in sheep: a morphological, immunohistochemical and PCR study after three years of infection

    Directory of Open Access Journals (Sweden)

    S Preziuso

    2009-06-01

    Full Text Available A morphological, immunohistochemical and polymerase chain reaction (PCR study was performed on eight ewes experimentally infected with an Italian strain of Maedi-Visna Virus (MVV in order to evaluate the lesions and the viral distribution after three years of infection. At the moment of euthanasia, seven sheep were seropositive for MVV, while one sheep in poor body conditions was seronegative since one year. Lungs, pulmonary lymph nodes, udder, supramammary lymph nodes, carpal joints, the CNS, spleen and bone marrow of the eight infected sheep were collected for histology, for immunohistochemical detection of the MVV core protein p28 and for PCR amplification of a 218 bp viral DNA sequence of the pol region. The most common histological findings consisted of interstitial lymphoproliferative pneumonia and lymphoproliferative mastitis of different severity, while no lesions were observed in the CNS. MVV p28 antigen was immunohistochemically labelled in lungs, udder, pulmonary lymph nodes, spleen and bone marrow but not in the CNS of all the eight infected sheep. A 218 bp sequence of MVV pol region was detected in lung of a seropositive and of the seroconverted negative sheep. The results suggest that (i MVV causes heterogeneous lesions in homogeneously reared ewes, (ii MVV p28 antigen is detectable not only in inflammed target organs, but also in pulmonary lymph nodes, spleen and bone marrow, and (iii immunohistochemistry and PCR are useful methods for Maedi-Visna diagnosis in suspected cases, also when serological tests are negative.

  18. Experimental infection with Escherichia coli 0149 : F4ac in weaned piglets

    DEFF Research Database (Denmark)

    Jensen, Gerda M.; Frydendahl, Kai; Svendsen, Ove

    2006-01-01

    adhesion test made after slaughter of piglets. However, in an experimental infection study with the purpose to obtain diarrhoeic piglets, it would be an advantage to test for susceptibility prior to experimentation. The Mucin 4 gene on porcine chromosome 13 has been proposed as a candidate gene...... for the production of the specific ETEC F4ab/ac receptor, and a DNA marker-based test has been developed to allow genotyping for ETEC F4ab/ac resistance/susceptibility [Jorgensen, C.B., Cirera, S., Archibald, A.L., Anderson, L., Fredholm, M., Edfors-Lilja, I., 2004. Porcine polymorphisms and methods for detecting...... them. International application published under the patent cooperation treaty (PCT). PCT/DK2003/000807 or WO2004/048606-A2]. The aim of this study was to test an experimental model for ETEC O149:F4ac-induced diarrhoea in piglets, selected for susceptibility towards ETEC O149:F4ac adhesion prior...

  19. Detection and distribution of ostreid herpesvirus 1 in experimentally infected Pacific oyster spat.

    Science.gov (United States)

    Segarra, Amélie; Baillon, Laury; Faury, Nicole; Tourbiez, Delphine; Renault, Tristan

    2016-01-01

    High mortality rates are reported in spat and larvae of Pacific oyster Crassostrea gigas and associated with ostreid herpesvirus 1 (OsHV-1) detection in France. Although the viral infection has been experimentally reproduced in oyster larvae and spat, little knowledge is currently available concerning the viral entry and its distribution in organs and tissues. This study compares OsHV-1 DNA and RNA detection and localization in experimentally infected oysters using two virus doses: a low dose that did not induce any mortality and a high dose inducing high mortality. Real time PCR demonstrated significant differences in terms of viral DNA amounts between the two virus doses. RNA transcripts were detected in oysters receiving the highest dose of viral suspension whereas no transcript was observed in oysters injected with the low dose. This study also allowed observing kinetics of viral DNA and RNA detection in different tissues of oyster spat. Finally, viral detection was significantly different in function of tissues (p<0.005), time (p<0.005) with an interaction between tissues and time (p<0.005) for each probe. Copyright © 2015 Elsevier Inc. All rights reserved.

  20. Cranberry juice and combinations of its organic acids are effective against experimental urinary tract infection

    DEFF Research Database (Denmark)

    Jensen, Heidi Dorthe; Struve, Carsten; Christensen, Søren Brøgger

    2017-01-01

    The antibacterial effect of cranberry juice and the organic acids therein on infection by uro28 pathogenic Escherichia coli was studied in an experimental mouse model of urinary tract infection (UTI). Reduced bacterial counts were found in the bladder (P ... administered singly, did not have any effect in the UTI model. Apparently, the antibacterial effect of the organic acids from cranberry juice on UTI can be obtained by administering a combination of malic acid and either citric or quinic acid. This study show for the first time that cranberry juice reduce E...

  1. A comparative study of clinical manifestations, haematological and serological responses after experimental infection with Anaplasma phagocytophilum in two Norwegian sheep breeds

    Directory of Open Access Journals (Sweden)

    Sandstedt Karin

    2011-02-01

    Full Text Available Abstract Background It has been questioned if the old native Norwegian sheep breed, Old Norse Sheep (also called Norwegian Feral Sheep, normally distributed on coastal areas where ticks are abundant, is more protected against tick-borne infections than other Norwegian breeds due to a continuously high selection pressure on pasture. The aim of the present study was to test this hypothesis in an experimental infection study. Methods Five-months-old lambs of two Norwegian sheep breeds, Norwegian White (NW sheep and Old Norse (ON sheep, were experimentally infected with a 16S rRNA genetic variant of Anaplasma phagocytophilum (similar to GenBank accession number M73220. The experiment was repeated for two subsequent years, 2008 and 2009, with the use of 16 lambs of each breed annually. Ten lambs of each breed were inoculated intravenously each year with 0.4 ml A. phagocytophilum-infected blood containing approximately 0.5 × 106 infected neutrophils/ml. Six lambs of each breed were used as uninfected controls. Half of the primary inoculated lambs in each breed were re-challenged with the same infectious dose at nine (2008 and twelve (2009 weeks after the first challenge. The clinical, haematological and serological responses to A. phagocytophilum infection were compared in the two sheep breeds. Results The present study indicates a difference in fever response and infection rate between breeds of Norwegian sheep after experimental infection with A. phagocytophilum. Conclusion Although clinical response seems to be less in ON-lambs compared to NW-lambs, further studies including more animals are needed to evaluate if the ON-breed is more protected against tick-borne infections than other Norwegian breeds.

  2. Experimental Infection and Detection of Necrotizing Hepatopancreatitis Bacterium in the American Lobster Homarus americanus

    Directory of Open Access Journals (Sweden)

    Luz A. Avila-Villa

    2012-01-01

    Full Text Available Necrotizing hepatopancreatitis bacterium (NHPB is an obligated intracellular bacteria causing severe hepatopancreatic damages and mass mortalities in penaeid shrimp. The worldwide distribution of penaeid shrimp as alien species threatens the life cycle of other crustacean species. The aim of the experiment was to evaluate the possibility of experimentally infecting the American lobster (Homarus americanus with NHPB extracted from shrimp hepatopancreas. Homogenates from infected shrimp were fed by force to lobsters. Other group of lobsters was fed with homogenates of NHPB-free hepatopancreas. After the 15th day from initial inoculation, the presence of NHPB was detected by polymerase chain reaction in feces and hepatopancreas from lobsters inoculated with infected homogenates. Necrotized spots were observed in the surface of lobster hepatopancreas. In contrast, lobsters fed on NHPB-free homogenates resulted negative for NHPB. Evidence suggests the plasticity of NHPB which can infect crustacean from different species and inhabiting diverse latitudes. Considering the results, the American lobster could be a good candidate to maintain available NHPB in vivo.

  3. Experimental Infection and Detection of Necrotizing Hepatopancreatitis Bacterium in the American Lobster Homarus americanus

    Science.gov (United States)

    Avila-Villa, Luz A.; Gollas-Galván, Teresa; Martínez-Porchas, Marcel; Mendoza-Cano, Fernando; Hernández-López, Jorge

    2012-01-01

    Necrotizing hepatopancreatitis bacterium (NHPB) is an obligated intracellular bacteria causing severe hepatopancreatic damages and mass mortalities in penaeid shrimp. The worldwide distribution of penaeid shrimp as alien species threatens the life cycle of other crustacean species. The aim of the experiment was to evaluate the possibility of experimentally infecting the American lobster (Homarus americanus) with NHPB extracted from shrimp hepatopancreas. Homogenates from infected shrimp were fed by force to lobsters. Other group of lobsters was fed with homogenates of NHPB-free hepatopancreas. After the 15th day from initial inoculation, the presence of NHPB was detected by polymerase chain reaction in feces and hepatopancreas from lobsters inoculated with infected homogenates. Necrotized spots were observed in the surface of lobster hepatopancreas. In contrast, lobsters fed on NHPB-free homogenates resulted negative for NHPB. Evidence suggests the plasticity of NHPB which can infect crustacean from different species and inhabiting diverse latitudes. Considering the results, the American lobster could be a good candidate to maintain available NHPB in vivo. PMID:22645497

  4. Fasciola hepatica: comparative metacercarial productions in experimentally-infected Galba truncatula and Pseudosuccinea columella

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    Vignoles Philippe

    2015-01-01

    Full Text Available As large numbers of metacercariae of Fasciola hepatica are necessary for research, experimental infections of Galba truncatula and Pseudosuccinea columella with this digenean were carried out to determine the better intermediate host for metacercarial production and, consequently, the most profitable snail for decreasing the cost price of these larvae. Pre-adult snails (4 mm in shell height originating from two populations per lymnaeid species were individually exposed to two or five miracidia, raised at 23 °C and followed for cercarial shedding up to their death. Compared to values noted in G. truncatula, the survival of P. columella on day 30 post-exposure was significantly greater, while the prevalence of F. hepatica infection was significantly lower. In the four P. columella groups, metacercarial production was significantly greater than that noted in the four groups of G. truncatula (347–453 per cercariae-shedding snail versus 163–275, respectively. Apart from one population of G. truncatula, the use of five miracidia per snail at exposure significantly increased the prevalence of F. hepatica in P. columella and the other population of G. truncatula, whereas it did not have any clear effect on the mean number of metacercariae. The use of P. columella for experimental infections with F. hepatica resulted in significantly higher metacercarial production than that noted with G. truncatula, in spite of a lower prevalence for the former lymnaeid. This finding allows for a significant decrease in the cost price of these larvae for commercial production.

  5. Analysis of experimental mink enteritis virus infection in mink: in situ hybridization, serology, and histopathology

    DEFF Research Database (Denmark)

    Uttenthal, Åse; Larsen, S; Lund, E

    1990-01-01

    Strand-specific hybridization probes were used in in situ hybridization studies to localize cells containing mink enteritis virus (MEV) virion DNA or MEV replicative-form DNA and mRNA. Following the experimental MEV infection of 3-month-old unvaccinated mink, a significant increase in serum antib...

  6. Pathogenesis of canine distemper virus in experimentally infected raccoon dogs, foxes, and minks.

    Science.gov (United States)

    Zhao, Jianjun; Shi, Ning; Sun, Yangang; Martella, Vito; Nikolin, Veljko; Zhu, Chunsheng; Zhang, Hailing; Hu, Bo; Bai, Xue; Yan, Xijun

    2015-10-01

    Canine distemper virus (CDV) infects a broad range of carnivores and causes a highly contagious disease with severe immunosuppression. The disease severity markedly varies in different species. To investigate the pathogenesis of CDV in raccoon dog (Nyctereutes procyonoides), fox (Vulpes vulpes) and mink (Neovison vison) species, three groups of CDV sero-negative animals were infected with CDV strain LN(10)1. This CDV strain belongs to the Asia-1 genotype, which is epidemiologically predominant in carnivores in China. CDV infection provoked marked differences in virulence in the three species that were studied. Raccoon dogs developed fever, severe conjunctivitis, and pathological lesions, with 100% (5/5) mortality and with high viral RNA loads in organs within 15 days post infection (dpi). In infected foxes, the onset of the disease was delayed, with 40% (2/5) mortality by 21 dpi. Infected minks developed only mild clinical signs and pathological lesions, and mortality was not observed. Raccoon dogs and foxes showed more severe immune suppression (lymphopenia, decreased lymphocyte proliferation, viremia and low-level virus neutralizing antibodies) than minks. We also observed a distinct pattern of cytokine mRNA transcripts at different times after infection. Decreased IFN-γ and IL-4 mRNA responses were evident in the animals with fatal disease, while up-regulation of these cytokines was observed in the animals surviving the infection. Increased TNF-α response was detected in animals with mild or severe clinical signs. Based on the results, we could distinguish three different patterns of disease after experimental CDV infection, e.g. a mild form in minks, a moderate form in foxes and a severe disease in raccoon dogs. The observed differences in susceptibility to CDV could be related to distinct host cytokine profiles. Comparative evaluation of CDV pathogenesis in various animal species is pivotal to generate models suitable for the evaluation of CDV

  7. Detection and quantification of pestivirus in experimentally infected pregnant ewes and their progeny

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    Juste Ramón A

    2009-11-01

    Full Text Available Abstract Background Border disease virus (BDV causes important reproductive losses, and eradication strategies focus on the identification and removal of persistently infected animals arising after in uterine infection. BDV infection dynamics were studied in 13 ewes experimentally infected with BDV-4 genotype at 3 phases of pregnancy [days 108 (group A, 76 (group B and 55 (group C] by quantification of viral RNA in blood collected on days -1 to parturition using quantitative real-time RT-PCR (qRT-PCR. Viral RNA loads were also measured in blood/foetal fluid and tissue samples from their offspring at lambing (3 foetuses, 7 stillborns, 15 lambs. qRT-PCR results were compared with those obtained by conventional RT-PCR and used to predict persistent infections. Results Viral RNA was detected in the ewes between days 2-15 p.i. The viraemia reached its highest peak between days 6-7 p.i. with a second peak at days 11-12 p.i. qRT-PCR was significantly faster to perform (less than 1 h than conventional RT-PCR and detected BDV RNA in more ewes, being detection more continuous and prolonged in time. The virus was detected in peripheral blood in a higher percentage of lambs than in tissues, where differences in viral genome copies were more marked. Skin and cerebral cortex showed the highest viral RNA loads, and spleen and spinal cord the lowest. High viral RNA loads were observed in several animals in group B and all in group C, infected during middle and early foetal development, respectively, but also in one lamb from group A, infected during late foetal development. Serology and viral genome copy number estimates in blood and tissues were used to establish a quantitative cut-off threshold for transient viraemia. Conclusion Viral RNA quantification showed potential for the discrimination between persistent infections and transient viraemia using single-time point blood sampling and raised questions regarding foetal immune system development and the

  8. Histological assessment of granulomas in natural and experimental Schistosoma mansoni infections using whole slide imaging.

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    Kátia B Amaral

    Full Text Available The pathology of schistosomiasis mansoni, a neglected tropical disease of great clinical and socioeconomic importance, results from the parasite eggs that become trapped in host tissues, particularly in the liver and intestines. Continuous antigenic stimulation from these eggs leads to recruitment of inflammatory cells to the sites of infection with formation of periovular granulomas. These complex structures have variable size and composition and are the most striking histopathological feature of schistosomiasis mansoni. However, evaluation of granulomas by conventional microscopy methods is time-consuming and limited, especially in large-scale studies. Here, we used high resolution Whole Slide Imaging (WSI, which allows fast scanning of entire histological slides, and multiple morphometric evaluations, to assess the granulomatous response elicited in target organs (liver, small and large intestines of two models of schistosomiasis mansoni. One of the advantages of WSI, also termed virtual microscopy, is that it generates images that simultaneously offer high resolution and a wide field of observation. By using a model of natural (Nectomys squamipes, a wild reservoir captured from endemic areas in Brazil and experimental (Swiss mouse infection with Schistosoma mansoni, we provided the first detailed WSI characterization of granulomas and other pathological aspects. WSI and quantitative analyses enabled a fast and reliable assessment of the number, evolutional types, frequency and areas of granulomas and inflammatory infiltrates and revealed that target organs are differentially impacted by inflammatory responses in the natural and experimental infections. Remarkably, high-resolution analysis of individual eosinophils, key cells elicited by this helminthic infection, showed a great difference in eosinophil numbers between the two infections. Moreover, features such as the intestinal egg path and confluent granulomas were uncovered. Thus, WSI may

  9. Prevalence of Toxoplasma gondii infection in wild birds in Durango, Mexico.

    Science.gov (United States)

    Alvarado-Esquivel, C; Rajendran, C; Ferreira, L R; Kwok, O C H; Choudhary, S; Alvarado-Esquivel, D; Rodríguez-Peña, S; Villena, I; Dubey, J P

    2011-10-01

    There is a lack of information concerning the prevalence of Toxoplasma gondii infection in wild birds in Mexico. In the present study, serum samples and tissues from 653 birds from Durango State, Mexico, were evaluated for T. gondii infection. Antibodies to T. gondii (modified agglutination test, titer 1∶25 or higher) were found in 17 (2.6%) of the 653 birds, including 1 of 2 curve-billed thrashers (Toxostoma curvirostre), 2 (1 Anas platyrhynchos, 1 Anas diazi) of 4 ducks, 1 of 2 eagles (Aquila sp.), 5 (27.8%) of 18 great-tailed grackles (Quiscalus mexicanus), 7 (1.3%) of 521 rock pigeons (Columba livia), and 1 (14.3%) of 7 quail (Coturnix coturnix). The seroprevalence of T. gondii infection in birds captured in a park outside the city zoo (11.6%, 8/69) was significantly higher than that found in birds from other regions (1.5%, 9/584, OR  =  8.38; 95% CI: 2.82-24.77; P  =  0.0001). Brains and hearts of 23 birds (17 seropositive, 6 seronegative) were bioassayed in mice for the isolation of T. gondii . Viable T. gondii was isolated from 1 of 7 seropositive pigeons. The DNA obtained from the T. gondii isolate from the pigeon was genotyped using the PCR-RFLP typing using 11 markers (B1, SAG1, SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1, and Apico) and revealed an atypical genotype. This is the first report of T. gondii infection in great-tailed grackles, the Mexican duck, and curved-billed thrashers and the first survey of wild birds in Mexico.

  10. Effect of wide spectrum anti-helminthic drugs upon Schistosoma mansoni experimentally infected mice

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    PANCERA Christiane Finardi

    1997-01-01

    Full Text Available Mebendazole, albendazole, levamisole and thiabendazole are well known as active drugs against several nematode species, and against cestodes as well, when the first two drugs are considered. None of the drugs have proven activity, however, against trematodes. We tested the effect of these drugs on the fecal shedding of schistosome eggs and the recovering of adult schistosomes, after portal perfusion in Schistosoma mansoni experimentally infected mice. Balb/c mice infected with 80 S. mansoni cercariae were divided into three groups, each in turn subdivided into four other groups, for each tested drug. The first group was treated with each one of the studied drugs 25 days after S. mansoni infection; the second group was submitted to treatment with each one of the drugs 60 days after infection. Finally, the third group, considered as control, received no treatment. No effect upon fecal shedding of S. mansoni eggs and recovering of schistosomes after portal perfusion was observed when mice were treated with either mebendazole or albendazole. Mice treated with either levamisole or thiabendazole, on the other hand, showed a significant reduction in the recovering of adult schistosomes after portal perfusion, mainly when both drugs were given during the schistosomula evolution period, i.e., 25 days after cercariae penetration, probably due to unspecific immunomodulation

  11. Experimental reproduction of beak atrophy and dwarfism syndrome by infection in cherry valley ducklings with a novel goose parvovirus-related parvovirus.

    Science.gov (United States)

    Chen, Hao; Dou, Yanguo; Tang, Yi; Zheng, Xiaoqiang; Niu, Xiaoyu; Yang, Jing; Yu, Xianglong; Diao, Youxiang

    2016-02-01

    Infection of clinically susceptible ducks, including cherry valley and Muscovy ducks, with a novel goose parvovirus (GPV)-related virus (N-GPV) can result in beak atrophy and dwarfism syndrome (BADS). To obtain new insights into the host range and pathogenic potential of this novel waterfowl parvovirus, cherry valley ducklings (n=20) were experimentally infected with N-GPV strain SDLC01. An equal number of ducklings served as uninfected controls. The appearance of clinical signs, histopathological changes, viral shedding, and seroconversion was monitored for 20 days post-infection. Infection status of all ducks was monitored using indirect ELISA, virus neutralization test, nested PCR, clinical indicators, and microscopic examination. Three ducks developed the typical clinical, gross, and histological changes of BADS. By study day 6, the infected ducks had seroconverted to N-GPV. The antibodies raised were neutralizing against the SDLC01 strain in vitro. Here we successfully developed an experimental infection model for studying the pathogenicity and role of N-GPV in BADS. Copyright © 2015 Elsevier B.V. All rights reserved.

  12. Therapy of the experimental infection by Strongyloides venezuelensis in rats with injectable ivermectin or levamizole

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    Rubens Campos

    1989-02-01

    Full Text Available For the therapy of human strongyloidiasis, are necessary effective drugs to eliminate both larvae and adult worm parasitism, which may also be used by parenteral route, to obviate the particular conditions presented by many patients. A study based on the experimental infection by Strongyloides venezuelensis in rats was done, administering injectable ivermectin or levamizole. Both drugs were shown to be active, when used in single doses of 0.2 to 0.5 mg/kg of ivermectin, or 26 mg/kg for levamizole. Ivermectin was slightly more effective as far as larval stage of the infection is concerned, and the same happened for levamisole for the adult worm stage. Promising perspectives are visualized to improve the therapy of patients with serious disseminated infection by Strongyloides stercoralis.

  13. Novel experimental Pseudomonas aeruginosa lung infection model mimicking long-term host-pathogen interactions in cystic fibrosis

    DEFF Research Database (Denmark)

    Moser, Claus; van Gennip, Maria; Bjarnsholt, Thomas

    2009-01-01

    Moser C, van Gennip M, Bjarnsholt T, Jensen PO, Lee B, Hougen HP, Calum H, Ciofu O, Givskov M, Molin S, Hoiby N. Novel experimental Pseudomonas aeruginosa lung infection model mimicking long-term host-pathogen interactions in cystic fibrosis. APMIS 2009; 117: 95-107. The dominant cause of premature...... death in patients suffering from cystic fibrosis (CF) is chronic lung infection with Pseudomonas aeruginosa. The chronic lung infection often lasts for decades with just one clone. However, as a result of inflammation, antibiotic treatment and different niches in the lungs, the clone undergoes...... and 2003) of the chronic lung infection of one CF patient using the seaweed alginate embedment model. The results showed that the non-mucoid clones reduced their virulence over time, resulting in faster clearing of the bacteria from the lungs, improved pathology and reduced pulmonary production...

  14. Experimental infection of plants with an herbivore-associated bacterial endosymbiont influences herbivore host selection behavior.

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    Thomas Seth Davis

    Full Text Available Although bacterial endosymbioses are common among phloeophagous herbivores, little is known regarding the effects of symbionts on herbivore host selection and population dynamics. We tested the hypothesis that plant selection and reproductive performance by a phloem-feeding herbivore (potato psyllid, Bactericera cockerelli is mediated by infection of plants with a bacterial endosymbiont. We controlled for the effects of herbivory and endosymbiont infection by exposing potato plants (Solanum tuberosum to psyllids infected with "Candidatus Liberibacter solanacearum" or to uninfected psyllids. We used these treatments as a basis to experimentally test plant volatile emissions, herbivore settling and oviposition preferences, and herbivore population growth. Three important findings emerged: (1 plant volatile profiles differed with respect to both herbivory and herbivory plus endosymbiont infection when compared to undamaged control plants; (2 herbivores initially settled on plants exposed to endosymbiont-infected psyllids but later defected and oviposited primarily on plants exposed only to uninfected psyllids; and (3 plant infection status had little effect on herbivore reproduction, though plant flowering was associated with a 39% reduction in herbivore density on average. Our experiments support the hypothesis that plant infection with endosymbionts alters plant volatile profiles, and infected plants initially recruited herbivores but later repelled them. Also, our findings suggest that the endosymbiont may not place negative selection pressure on its host herbivore in this system, but plant flowering phenology appears correlated with psyllid population performance.

  15. Assessment of experimental infection for dogs usingGallus gallus chorioallantoic membranes inoculated withNeospora caninum

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    Alexandre Dias Munhoz

    Full Text Available The aim of this study was to evaluate parasitism kinetics and tissue lesions in the first week of infection by Neospora caninum in dogs fed Gallus gallus chorioallantoic membranes (CMs previously infected in ovo. Five two-month-old pups were used. Each dog was given five CMs that were previously infected with N. caninum via the oral route. Four animals were euthanized in the first week of infection. All four dogs had their stools examined one week prior to and up to the day they were euthanized. The stools of the uneuthanized dog were collected for 30 days. After euthanasia, organ sections were utilized for histopathology, immunohistochemistry, indirect immunofluorescent tissue reactions, PCR and real-time PCR to detect parasites. Necropsy revealed that the small and large intestines, spleen, and lungs were affected. No oocysts orN. caninum DNA were identified in the stool samples. Real-time PCR was the most sensitive technique used to detect the protozoa in tissues, which were identified in 41% of the analyzed samples. Our results indicate that an experimental model using previously infected CMs appears to be a useful model for the study of the host-parasite relationship during the infection's acute phase.

  16. Experimental infection of two South American reservoirs with four distinct strains of Trypanosoma cruzi

    Science.gov (United States)

    Roellig, Dawn M.; McMillan, Katherine; Ellis, Angela E.; Vandeberg, John L.; Champagne, Donald E.; Yabsley, Michael J.

    2010-01-01

    SUMMARY Trypanosoma cruzi (Tc), the causative agent of Chagas disease, is a diverse species with 2 primary genotypes, TcI and TcII, with TcII further subdivided into 5 subtypes (IIa–e). This study evaluated infection dynamics of 4 genetically and geographically diverse T. cruzi strains in 2 South American reservoirs, degus (Octodon degus) and grey short-tailed opossums (Monodelphis domestica). Based on prior suggestions of a genotype-host association, we hypothesized that degus (placental) would more readily become infected with TcII strains while short-tailed opossums (marsupial) would be a more competent reservoir for a TcI strain. Individuals (n = 3) of each species were intraperitoneally inoculated with T. cruzi trypomastigotes of TcIIa [North America (NA)-raccoon (Procyon lotor) origin], TcI [NA-Virginia opossum (Didelphis virginiana)], TcIIb [South America (SA)-human], TcIIe (SA-Triatoma infestans), or both TcI and TcIIa. Parasitaemias in experimentally infected degus peaked earlier (7–14 days post-inoculation (p.i.)) compared with short-tailed opossums (21–84 days p.i.). Additionally, peak parasitaemias were higher in degus; however, the duration of detectable parasitaemias for all strains, except TcIIa, was greater in short-tailed opossums. Infections established in both host species with all genotypes, except for TcIIa, which did not establish a detectable infection in short-tailed opossums. These results indicate that both South American reservoirs support infections with these isolates from North and South America; however, infection dynamics differed with host and parasite strain. PMID:20128943

  17. Comparative Experimental Infection Study in Dogs with Ehrlichia canis, E. chaffeensis, Anaplasma platys and A. phagocytophilum.

    Science.gov (United States)

    Nair, Arathy D S; Cheng, Chuanmin; Ganta, Chanran K; Sanderson, Michael W; Alleman, Arthur R; Munderloh, Ulrike G; Ganta, Roman R

    2016-01-01

    Dogs acquire infections with the Anaplasmataceae family pathogens, E. canis, E. chaffeensis, E. ewingii, A. platys and A. phagocytophilum mostly during summer months when ticks are actively feeding on animals. These pathogens are also identified as causing diseases in people. Despite the long history of tick-borne diseases in dogs, much remains to be defined pertaining to the clinical and pathological outcomes of infections with these pathogens. In the current study, we performed experimental infections in dogs with E. canis, E. chaffeensis, A. platys and A. phagocytophilum. Animals were monitored for 42 days to evaluate infection-specific clinical, hematological and pathological differences. All four pathogens caused systemic persistent infections detectible throughout the 6 weeks of infection assessment. Fever was frequently detected in animals infected with E. canis, E. chaffeensis, and A. platys, but not in dogs infected with A. phagocytophilum. Hematological differences were evident in all four infected groups, although significant overlap existed between the groups. A marked reduction in packed cell volume that correlated with reduced erythrocytes and hemoglobin was observed only in E. canis infected animals. A decline in platelet numbers was common with E. canis, A. platys and A. phagocytophilum infections. Histopathological lesions in lung, liver and spleen were observed in all four groups of infected dogs; infection with E. canis had the highest pathological scores, followed by E. chaffeensis, then A. platys and A. phagocytophilum. All four pathogens induced IgG responses starting on day 7 post infection, which was predominantly comprised of IgG2 subclass antibodies. This is the first detailed investigation comparing the infection progression and host responses in dogs after inoculation with four pathogens belonging to the Anaplasmataceae family. The study revealed a significant overlap in clinical, hematological and pathological changes resulting from the

  18. Evaluation of metaphylactic RNA interference to prevent equine herpesvirus type 1 infection in experimental herpesvirus myeloencephalopathy in horses.

    Science.gov (United States)

    Perkins, Gillian A; Van de Walle, Gerlinde R; Pusterla, Nicola; Erb, Hollis N; Osterrieder, Nikolaus

    2013-02-01

    To evaluate metaphylactic RNA interference to prevent equine herpesvirus type 1 (EHV-1) infection in experimental herpesvirus myeloencephalopathy in horses and to determine whether horses infected with a neuropathogenic strain of the virus that develop equine herpesvirus myeloencephalopathy (EHM) have differences in viremia. 13 seronegative horses. EHV-1 strain Ab4 was administered intranasally on day 0, and small interfering RNAs (siRNAs [EHV-1 specific siRNAs {n = 7} or an irrelevant siRNA {6}]) were administered intranasally 24 hours before and 12, 24, 36, and 48 hours after infection. Physical and neurologic examinations, nasal swab specimens, and blood samples were collected for virus isolation and quantitative PCR assay. Data from the study were combined with data from a previous study of 14 horses. No significant difference was detected in clinical variables, viremia, or detection of EHV-1 in nasal swab specimens of horses treated with the EHV-1 targeted siRNAs (sigB3-siOri2) versus controls. No significant differences in viremia were detected between horses that developed EHM and those that did not. Administration of siRNAs targeted against EHV-1 around the time of EHV-1 infection was not protective with this experimental design. Horses infected with the neuropathogenic EHV-1 strain Ab4 that developed EHM did not have a more pronounced viremia.

  19. Use of quantitative real-time RT-PCR to investigate the correlation between viremia and viral shedding of canine distemper virus, and infection outcomes in experimentally infected dogs.

    Science.gov (United States)

    Sehata, Go; Sato, Hiroaki; Ito, Toshihiro; Imaizumi, Yoshitaka; Noro, Taichi; Oishi, Eiji

    2015-07-01

    We used real-time RT-PCR and virus titration to examine canine distemper virus (CDV) kinetics in peripheral blood and rectal and nasal secretions from 12 experimentally infected dogs. Real-time RT-PCR proved extremely sensitive, and the correlation between the two methods for rectal and nasal (r=0.78, 0.80) samples on the peak day of viral RNA was good. Although the dogs showed diverse symptoms, viral RNA kinetics were similar; the peak of viral RNA in the symptomatic dogs was consistent with the onset of symptoms. These results indicate that real-time RT-PCR is sufficiently sensitive to monitor CDV replication in experimentally infected dogs regardless of the degree of clinical manifestation and suggest that the peak of viral RNA reflects active CDV replication.

  20. Effects of Ichthyophonus hoferi on condition indices and blood chemistry of experimentally infected rainbow trout (Oncorhynchus mykiss).

    Science.gov (United States)

    Rand, T G; Cone, D K

    1990-07-01

    Body condition, hepatosomatic index and blood chemistry of Oncorhynchus mykiss experimentally infected with a tissue dwelling fish pathogenic fungus, Ichthyophonus hoferi, were monitored over a 6 wk period. This was to determine whether the infection constituted a stress manifest by changes in the hypothalamic-pituitary interrenal axis, and especially plasma cortisol levels. Infection caused anaemia and leucopenia but did not change the condition, hepatosomatic indices, or plasma chloride, cholesterol, cortisol, creatinine, glucose, osmolarity, potassium, total protein, sodium and T4. It is suggested that increased cortisol levels may not be a normal component of the stress response of fish to disease caused by invasive infectious agents.

  1. Effects of single or trickle Haemonchus contortus experimental infection on digestibility and host responses of naïve Creole kids reared indoor.

    Science.gov (United States)

    Bambou, J C; Cei, W; Camous, S; Archimède, H; Decherf, A; Philibert, L; Barbier, C; Mandonnet, N; González-García, E

    2013-01-31

    The objective of this study was to compare the effects of the type of Haemonchus contortus experimental infection (trickle infection, TI versus single infection, SI) on feed intake, nutrients digestibility, parasitological and haematological measures, and plasma leptin in Creole kids. The animals were infected over 2 periods (challenge 1 and challenge 2) of 6 weeks each, corresponding respectively to the primary and the secondary infection. Periods prior infection (1 week each) were considered as controls. The primary infection was realized with 35 Creole kids (18.40±3.76 kg BW) housed in individual boxes and fed a hay-based diet. The secondary infection continued with 29 kids (21.90±3.40 kg BW) from the initial 35. A total of 6 kids and 8 kids were slaughtered for measuring nematode burden at the end of the primary and the secondary infection, respectively. Measurements of nutrients digestibility were made at 0, 3 and 5 weeks post-infection for both challenges. Faecal egg count (FEC), blood eosinophilia and packed cell volume (PCV) were monitored weekly. Feed intake (dry matter intake, DMI) and nutrients digestibility were negatively affected by H. contortus infection only during the primary infection. Plasma leptin changed significantly over time (P=0.0002) but was not affected by the infection type. Effect of infection type was observed only on crude protein digestibility during the primary infection, which was lower in the TI group (P<0.01). The overall level of blood eosinophilia was significantly higher in the TI group (P<0.0001) during both challenges. The overall FEC mean was significantly higher in the SI compared with the TI groups, during both challenges (P<0.02). These results were related to the mean female length significantly higher in the SI group compared with the TI group during challenge 1 (P=0.004), and the number of adult nematode significantly lower in the TI group compared with the SI group during the challenge 2 (P=0.05). The results

  2. Sympatric and allopatric experimental infections of the planorbid snail Gyraulus chinensis with miracidia of Euparyphium albuferensis (Trematoda: Echinostomatidae).

    Science.gov (United States)

    Muñoz-Antoli, C; Marín, A; Trelis, M; Toledo, R; Esteban, J-G

    2010-12-01

    An experimental infection with echinostomatid miracidia in sympatric or 'local' vs. allopatric or 'away' snail combinations, as a model to examine parasite compatibility, was carried out. We employed Euparyphium albuferensis miracidia to infect Gyraulus chinensis snails, from three different natural parks: Albufera (Valencia, Spain); the Ebro Delta (Tarragona, Spain) and Coto de Doñana (Huelva, Spain). Insignificant differences between the three snail strains were noted for the infection rate and the rhythm of daily cercarial production. However, a significantly higher total cercarial production per snail, patent period and life span were observed in local snails. The different infection characteristics in the three G. chinensis strains considered reveal that E. albuferensis miracidia demonstrate local adaptation.

  3. IL-18 potentiated whole blood IFN-γ assay can identify cell-mediated immune responses towards Lawsonia intracellularis in experimentally infected pigs

    DEFF Research Database (Denmark)

    Riber, Ulla; Jakobsen, Jeanne Toft; Hvass, Henriette Cordes

    Lawsonia intracellularis is an obligate intracellular bacteria causing proliferative enteropathy (PE) in pigs. The infection causes diarrhoea, retarded growth and sudden death in pigs and is one of the most economically important diseases in the swine industry worldwide. The infection is one...... indications that cell-mediated immune responses (CMI) are important for the protection against infections with L. intracellularis and in mice models IFN-γ has been shown to play a key role in the host defence against experimental infections . In L. intracellularis infected pigs, IFN-γ is only sparsely...

  4. Potential Role of Carvedilol in the Cardiac Immune Response Induced by Experimental Infection with Trypanosoma cruzi

    Directory of Open Access Journals (Sweden)

    Aline Luciano Horta

    2017-01-01

    Full Text Available Trypanosoma cruzi causes a cardiac infection characterized by an inflammatory imbalance that could become the inciting factor of the illness. To this end, we evaluated the role of carvedilol, a beta-blocker with potential immunomodulatory properties, on the immune response in C57BL/6 mice infected with VL-10 strain of T. cruzi in the acute phase. Animals (n=40 were grouped: (i not infected, (ii infected, (iii infected + carvedilol, and (iv not infected + carvedilol. We analyzed parameters related to parasitemia, plasma levels of TNF, IL-10, and CCL2, and cardiac histopathology after the administration of carvedilol for 30 days. We did not observe differences in the maximum peaks of parasitemia in the day of their detection among the groups. The plasma TNF was elevated at 60 days of infection in mice treated or not with carvedilol. However, we observed a decreased CCL2 level and increased IL-10 levels in those infected animals treated with carvedilol, which impacted the reduction of the inflammatory infiltration in cardiac tissue. For this experimental model, carvedilol therapy was not able to alter the levels of circulating parasites but modulates the pattern of CCL2 and IL-10 mediators when the VL10 strain of T. cruzi was used in C57BL6 mice.

  5. Experimental infection in Cavia porcellus by infected Amblyomma ovale nymphs with Rickettsia sp. (Atlantic rainforest strain).

    Science.gov (United States)

    Brustolin, Joice Magali; da Silva Krawczak, Felipe; Alves, Marta Elena Machado; Weiller, Maria Amélia; de Souza, Camila Lopes; Rosa, Fábio Brum; Cadore, Gustavo Cauduro; Dos Anjos Lopes, Sônia Terezinha; Labruna, Marcelo Bahia; Vogel, Fernanda Silveira Flores; de Avila Botton, Sônia; Sangioni, Luís Antônio

    2018-03-01

    This study describes experimental infection of guinea pigs (Cavia porcellus) infested with naturally infected Amblyomma ovale nymphs with Rickettsia sp. (Atlantic rainforest strain), and the capacity of A. ovale nymphs to transmit this bacterium. Twenty-six guinea pigs were divided into the following groups: G1, 10 animals infested with uninfected A. ovale nymphs; G2, 10 animals infested with nymphs infected with Rickettsia sp. (Atlantic rainforest strain); and G3, 6 animals without tick infestation. Blood samples were taken 7, 14, 21, and 28 days post-infestation for serological and hematological tests. For histopathological analysis and rickettsial DNA detection, fragments of the spleen, lung, brain, and liver were harvested after euthanasia. The average feeding period for nymphs was 6.6 days for G1 and 6 days for G2. Hemolymph and PCR assays, performed to detect the causative agent in ticks, indicated that in G1, all ticks were negative, and in G2, all nymphs were positive by PCR and 80% (8/10) was positive by hemolymph tests. The only clinical change was skin scarring at the tick attachment site. Hematological parameters indicated leukopenia and total plasma protein (TPP) increased with decreased platelets in G1. In G2, leukocytosis, neutrophilia, monocytosis, an increase in platelets, and reduced TPP were observed. Only G2 guinea pigs were seroconverted (80%; 8/10). Histopathology tests indicated mild, diffuse hemosiderosis and mild, multifocal, follicular hyperplasia in the spleen. Molecular analysis did not detect Rickettsia sp. DNA in C. porcellus tissues. We demonstrated the capacity of A. ovale nymphs to transmit Rickettsia sp. (Atlantic rainforest strain) to guinea pigs.

  6. Immune responsiveness associated with experimental Encephalitozoon intestinalis infection in immunocompetent rats

    Directory of Open Access Journals (Sweden)

    Omalu ICJ

    2007-01-01

    Full Text Available Purpose: Microsporidial infections have been recognized as an increasingly important infection in immuncompromised patients, particularly those infected with HIV/AIDS. This study was designed to study immune responses associated with experimental Encephalitozoon intestinalis infection in immunocompetent rats. Materials and Methods: Thirty-four Rats in 3 groups, A (Control, B (Intraperitoneal and C (Oral were given injections of 0.5 ml of 2 x 10 6 of purified spores of Encephalitotozoon intestinalis spores and were observed for serum specific IgG for 21 days using both direct and indirect ELISA. Results: In indirect ELISA, specific lgG were detected on days 7, 14 and 21 for the group B rats and on day 21 for group C and in direct ELISA method, specific lgG were detected in-group B rats on days 7 and 21, for group C rats on day 21 only, while in the control rats, specific lgG were not detected. There was no significant difference between the direct and indirect methods (df=1, X 2 , P>0.05. E. intestinalis was observed in stool samples of rats in 1/12 (08.33% on days 14 and 21 in group B, and in 4/10 (33.33%, 3/10 (25.00% and 2/10 (16.67% on days 7, 14 and 21 respectively in group C. In group A, which is the control rats, no microsporidia were observed on days 0, 7, 14 and 21. Conclusions: There were no changes in the T-lymphocyte counts of rats prior to and after inoculation with spores. Extensive lesions were observed along the intestinal walls especially on the middle and lower sections of group C rats only.

  7. Body mass, wing length, and condition of wintering ducks relative to hematozoa infection

    Science.gov (United States)

    Fleskes, Joseph; Ramey, Andrew M.; Reeves, Andrew; Yee, Julie L.

    2017-01-01

    Waterfowl managers lack information regarding factors that may be reducing the positive response of waterfowl body condition to habitat improvements. Protozoan blood parasites (i.e., hematozoa) are commonly found in birds and have been related to reduced body mass, wing length, and body condition. We studied relationships between 12 measures of hematozoa infection and body mass, wing length, and body mass divided by wing length (i.e., body condition index [BCI]) of the five most common duck species (northern pintail [Anas acuta], mallard [A. platyrhynchos], green-winged teal [A. crecca], American wigeon [A. Americana], northern shoveler [A. clypeata]) wintering in the Central Valley of California during October 2006-January 2007. After accounting for variation due to species, age-sex cohort, Central Valley region, and month; wing length, body mass, and BCI were found to be negatively related to infection by Leucocytozoon and by "any hematozoa" but not related to infection by only Plasmodium or Haemoproteus, or coinfections of greater than one genera or parasite haplotype (albeit, few ducks had Plasmodium or Haemoproteus infection or coinfections). Evidence of a negative relationship with infection was stronger for body mass and BCI than for wing length and indicated that the relationships varied among species, age-sex cohorts, regions, and months. Compared to uninfected ducks, hematozoa-infected duck body mass, wing length, and BCI was -1.63% (85% CI = -2.79%- -0.47%), -0.12% (-0.41%- +0.17%), and -1.38% (-2.49%- -0.26%), respectively. Although, seemingly small, the -1.63% difference in body mass represents a large percentage (e.g., 38% for northern pintail) of the observed increase in wintering duck body mass associated with Central Valley habitat improvements. Because infection prevalence and relationship to body condition might change over time due to climate or other factors, tracking hematozoa infection prevalence might be important to inform and accurately

  8. Antibacterial efficacy of ethyl acetate fraction of Psidium guajava leaf aqueous extract on experimental Escherichia coli (O78) infection in chickens.

    Science.gov (United States)

    Geidam, Y A; Ambali, A G; Onyeyili, P A; Tijjani, M B; Gambo, H I; Gulani, I A

    2015-03-01

    This study was desingned to examine the efficacy of ethyl acetate fraction of aqueous extracted Psidium guajava leaves on chicks experimentally-infected with diarrheagenic strain of Escherichia coli O78. A total of 60 ISA brown male chicks were randomly divided into 6 Groups of ten chicks each in separate cages. Group A was not infected and not treated. Groups B, C and D were infected and treated with extracts at a dose of 25, 50 and 100 mg/kg respectively for 10 days. Group E was infected and treated with oxytetracycline while Group F was infected, but left untreated. Chicks from all groups were closely monitored for clinical signs, body weight change and fecal bacterial shedding load during the course of the experiment. Diarrhea, vents pasted with feces, drop in feed intake accompanied by slow weight gain and decreased activity was observed in infected untreated groups. Groups treated with graded doses of the extract experienced a dose-dependent decreased in severity of the clinical signs shown compared to the infected untreated group. Bacterial shedding load was found to be lower in groups treated with the extract and oxytetracycline than those without intervention. Ethyl acetate soluble fraction of leaf extract of Psidium guajava effectively controlled diarrhea and decreased the severity of other clinical signs caused by experimental E. coli infections in chicks.

  9. In situ hybridization for the detection of infectious laryngotracheitis virus in sections of trachea from experimentally infected chickens

    DEFF Research Database (Denmark)

    Nielsen, O.L.; Handberg, Kurt; Jørgensen, Poul Henrik

    1998-01-01

    An in situ hybridization procedure for the detection of infectious laryngotracheitis virus (ILTV) in experimentally infected chickens is described. Formalin-fixed, paraffin-embedded sections of trachea, taken from chickens on days 3-10 post-inoculation (p.i.) with ILTV were hybridized with a mixt......An in situ hybridization procedure for the detection of infectious laryngotracheitis virus (ILTV) in experimentally infected chickens is described. Formalin-fixed, paraffin-embedded sections of trachea, taken from chickens on days 3-10 post-inoculation (p.i.) with ILTV were hybridized...... on day 5 p.i. No hybridization was observed in 3 out of 3 chickens examined on day 10 p.i. ILTV nucleic acid was detected in nuclei of degenerated tracheal epithelial cells and in intranuclear inclusion bodies of syncytia....

  10. Effect of dietary supplementation on resistance to experimental infection with Haemonchus contortus in Creole kids.

    Science.gov (United States)

    Bambou, J C; Archimède, H; Arquet, R; Mahieu, M; Alexandre, G; González-Garcia, E; Mandonnet, N

    2011-06-10

    The aim of the present study was to test the effect of dietary supplementation on resistance to experimental infection with Haemonchus contortus in Creole kids. One trial with three replicates involved a total of 154 female kids that were chosen from three successive cohorts of the Creole flock of INRA-Gardel in 2007. The kids were placed into four treatments according to the amount of concentrate they received: G0 (no concentrate and a quality Dichantium spp. hay ad libitum, HAY), G1 (HAY+100g commercial concentrate d(-1)), G2 (HAY+200 g commercial concentrate d(-1)), G3 (HAY+300 g commercial concentrate d(-1)). The G0-G3 groups were infected with a single dose of 10,000 H. contortus third stage larvae (L(3)) at Day 0 (D0). Each infected group was comprised of one half resistant and one half susceptible genetically indexed kids. The average breeding values on egg excretion at 11 months of age were distant of 0.70, 0.65, 0.61 and 0.61 genetic standard deviations in G0, G1, G2 and G3, respectively. The faecal egg count (FEC), packed cell volume (PCV), eosinophilia (EOSI) and dry matter intake (DMI) indices were monitored weekly until 42 days post-infection. Enzyme-linked immunosorbent assay was carried out on serum samples to determine the level of IgA anti-H. contortus L(3) crude extracts and adult excretion/secretion products (ESP). The 10,000 L(3) dose received by the kids induced a severe infection: 8000 eggs per gram at the FEC peak, a PCV less than 15% and mortality. Interestingly, the supplemented animals in G3 showed a higher level of EOSI but a lower level of IgA anti-L3 and IgA anti-ESP than non-supplemented animals (G0). Resistant and susceptible kids had significantly different FEC variations within the groups. Susceptible kids had a 1.6 times higher egg output than resistant kids in G0. This difference was not found in the supplemented groups. The results of this study showed that supplementary feeding improved resistance of Creole kids to H. contortus

  11. Toxoplasma gondii: infection natural congenital in cattle and an experimental inoculation of gestating cows with oocysts.

    Science.gov (United States)

    Costa, Gustavo Henrique Nogueira; da Costa, Alvimar José; Lopes, Welber Daniel Zanetti; Bresciani, Katia Denise Saraiva; dos Santos, Thais Rabelo; Esper, César Roberto; Santana, Aureo Evangelista

    2011-01-01

    Two studies, of a natural infection and an experimental infection, were performed in order to study congenital transmission of Toxoplasma gondii in cattle. In the first study, 50 fetuses were harvested from gestating cows that were eutanasied at a municipal slaughterhouse in Jaboticabal, São Paulo state, Brazil. In the second study, 11 gestating cows were divided into four groups for inoculation with T. gondii: GI consisted of three cows inoculated with 1.0 × 10(5) oocysts during their first trimester of gestation; GII consisted of three cows inoculated with 1.0 × 10(5) oocysts during their second trimester of gestation; GIII consisted of three cows inoculated with 1.0 × 10(5) oocysts during their last trimester of gestation; and GIV consisted of two control cows, one during its first and the other during its second trimester of gestation. In both studies, the presence of T. gondii was confirmed both indirectly by immunofluorescence assay (IFAT). In the natural infection experiment, 18% (9/50) of the gestating cows were confirmed to have specific antibodies (IFAT--1:64) against T. gondii. The bioassay was able to diagnose the presence of T. gondii in the tissue samples from three calves. In the second experiment, the nine cows from groups I, II and III presented with specific antibodies (IFAT) against T. gondii. In contrast, T. gondii could not be detected by IFAT, histopathological examination or the bioassay in any of the nine calves born to cows experimentally infected with T. gondii oocysts. Based on the results from both studies, we conclude that congenital infection of T. gondii in cattle, while infrequent, does occur naturally. The pathogenicity of the strain of T. gondii may influence the likelihood of this route of transmission. Copyright © 2010 Elsevier Inc. All rights reserved.

  12. Aspects of resistance to experimental infection with Trypanosoma cruzi

    International Nuclear Information System (INIS)

    Dias, Viviane Liotti

    2010-01-01

    Chagas disease, a zoonosis caused by the protozoan Trypanosoma cruzi, has a wide distribution in Latin America and extends from the southern part of the United States to Argentina. A number of 10 million of infected people is estimated and another 25 million exposed to the risk. Although discovered over a century, Chagas disease is still a serious infection that causes great socioeconomic impact, with no effective treatment at the chronic phase and in which, a lack of scientific knowledge can be observed. The main goal of this work was that obtaining and using consomic strain of mice, the resistance could be investigated. Consomic strains were produced by programmed mating, in which the animals were monitored with DNA polymorphic markers, and one of his chromosomes was replaced by his homologue from another strain. As parental, were used, the inbred strains C57BL/6/J Unib with resistant phenotype (donor) and as receiver, the A/JUnib strain, that has a susceptible phenotype. These models were used to produce five consomic strains: for the chromosomes 7 (CSs7), 11 (CSs11), 14 (CSs14), 17 (CSs17) and 19 (CSs19), described by Passos et al. (2003) as important in controlling infection caused by the Y strain of T. cruzi. In experimental testing, the consomics were inoculated intraperitoneally at doses of 10 1 , 10 2 , 10 3 and 10 4 using as control, animals from both parental lines. In all consomics, resistance was higher than that observed in the susceptible parental. In a second protocol, the consomics were mated with scheduled associations and the progenies were challenged with inocula employing increasing doses of trypomastigotes. The resistance observed in this group was also higher than that observed in the parental with susceptible phenotype. The observed results demonstrate that the use of the consomic strains that were produced order to assess the contribution of each chromosome in the resistance, as well as the effects of association between chromosomes are an

  13. Aberrant chlamydial developmental forms in the gastrointestinal tract of pigs spontaneously and experimentally infected with Chlamydia suis.

    Science.gov (United States)

    Pospischil, Andreas; Borel, Nicole; Chowdhury, Emdad H; Guscetti, Franco

    2009-03-16

    The phenomenon of persistence is well known from in vitro studies, where it is associated with the production of aberrant bodies, but its occurrence in vivo is less well documented. The objective of this study was to search for aberrant bodies in intestinal tissues from pigs, describe their ultrastructure, and investigate the suitability of immunohistochemical staining for chlamydial heat shock protein 60 (cHSP60) to detect such forms. Intestinal tissues derived from pigs naturally and experimentally infected with Chlamydia (C.) suis were examined by immunohistochemistry, transmission electron microscopy and immunogold electron microscopy. The chlamydial species involved in the natural infection were determined using an Array Tube Microarray to C. suis and Chlamydophila abortus. Ultrastructurally, aberrant bodies were detected in the gut of both naturally and experimentally infected pigs. Immunogold electron microscopy showed that the aberrant bodies were labeled less strongly than the normal forms by antibodies against LPS and cHSP60 respectively. It was concluded that aberrant bodies occur in vivo in pigs and that the gnotobiotic pig model might be suitable for the study of chlamydial persistence in vivo. The antibody against cHSP60 does not appear to be suitable to specifically detect such forms.

  14. Histopathological and parasitological investigations of ear healthy skin of dogs naturally and experimentally infected with Leishmania (Leishmania) chagasi.

    Science.gov (United States)

    Figueiredo, Maria Marta; Moura, Eliane Perlatto; Costa, Miriam Maria; Ribeiro, Vitor Marcio; Michalick, Marilene Suzan; Tafuri, Washington Luiz; Tafuri, Wagner Luiz

    2010-07-01

    Although 90% of clinical cases of American visceral leishmaniasis (AVL) occur in the northeastern region of Brazil, the incidence of cases in recent years has increased in southeastern states such as Minas Gerais (MG), where the disease has been reported in several cities, including Belo Horizonte, the state capital. Some studies have shown a strong correlation between the incidence of AVL and canine visceral leishmaniasis (CVL) in Belo Horizonte. A study of 108 dogs with parasite Leishmania chagasi detected by immuno-histochemistry in healthy ear skin was obtained from two distinct geographical areas: 55 from a metropolitan area of the municipality (Santa Luzia, MG) and 53 dogs from a central area of Belo Horizonte. In parallel, a group of 10 beagles were experimentally infected with L. chagasi. Considering the clinical aspects of all naturally infected dogs, symptomatic dogs were more frequent than asymptomatic ones, especially animals from the metropolitan area compared with the central area (79.6% and 20.3%, respectively). A chronic exudate was observed in the ear of 51 out of 55 dogs naturally infected from the metropolitan area (92.7%) and 45 out of 53 dogs naturally infected from the central area (84.9%). Importantly, asymptomatic dogs from the central area harbor more parasites in the skin than the asymptomatic ones from the metropolitan area. In addition, a profound difference was noted in the intensity of the inflammatory reaction and parasite load in the skin of experimental infected dogs.

  15. Efficiency of oxytetracycline treatment in rainbow trout experimentally infected with Flavobacterium psychrophilum strains having different in vitro antibiotic susceptibilities

    DEFF Research Database (Denmark)

    Bruun, Morten Sichlau; Madsen, Lone; Dalsgaard, Inger

    2003-01-01

    The medication effect of oxytetracycline on groups of rainbow trout fry experimentally infected with three strains of Flavobacterium psychrophilum was investigated. The infection model was based on intraperitoneal injection of the pathogen and treatment was done using medicated feed resulting...... in 100 mg oxytetracycline/kg fish for 10 days. The three F. psychrophilum strains had different antimicrobial susceptibilities and successful treatment was only obtained in the trial using a strain with a MICOTC of 0.25 mug/ml. No effect of treatment was seen in the group infected with a strain having...

  16. The Leishmania HSP20 Is Antigenic during Natural Infections, but, as DNA Vaccine, It does not Protect BALB/c Mice against Experimental L. amazonensis Infection

    Directory of Open Access Journals (Sweden)

    Ana M. Montalvo-Álvarez

    2008-01-01

    Full Text Available Protozoa of the genus Leishmania are causative agents of leishmaniasis, an important health problem in both human and veterinary medicine. Here, we describe a new heat shock protein (HSP in Leishmania, belonging to the small HSP (sHSP family in kinetoplastids. The protein is highly conserved in different Leishmania species, showing instead significant divergence with sHSP's from other organisms. The humoral response elicited against this protein during Leishmania infection has been investigated in natural infected humans and dogs, and in experimentally infected hamsters. Leishmania HSP20 is a prominent antigen for canine hosts; on the contrary, the protein seems to be a poor antigen for human immune system. Time-course analysis of appearance of anti-HSP20 antibodies in golden hamsters indicated that these antibodies are produced at late stages of the infection, when clinical symptoms of disease are patent. Finally, the protective efficacy of HSP20 was assessed in mice using a DNA vaccine approach prior to challenge with Leishmania amazonensis.

  17. Experimental treatment with sodium stibogluconate of hamsters infected with Leishmania (Leishmania) chagasi and Leishmania (Leishmania) amazonensis Tratamento experimental com stibogluconato de sódio em hamsters infectados com Leishmania (Leishmania) chagasi e Leishmania (Leishmania) amazonensis

    OpenAIRE

    Elizabeth M. de Figueiredo; Jaime Costa e Silva; Reginaldo P. Brazil

    1999-01-01

    The present paper reports the experimental treatment of hamsters infected with Leishmania chagasi and Leishmania amazonensis with sodium stibogluconate (20mg/kg/day x 20 days). Only with L. chagasi did the treatment result in the complete elimination of parasites from the spleen. However, no parasitological cure was achieved in hamsters infected with L. amazonensis.O presente trabalho é um relato do tratamento experimental de hamsters infectado com Leishmania chagasi e Leishmania amazonensis ...

  18. Experimental infection of snakes with Ophidiomyces ophiodiicola causes pathological changes that typify snake fungal disease

    Science.gov (United States)

    Lorch, Jeffrey M.; Lankton, Julia S.; Werner, Katrien; Falendysz, Elizabeth A.; McCurley, Kevin; Blehert, David S.

    2015-01-01

    Snake fungal disease (SFD) is an emerging skin infection of wild snakes in eastern North America. The fungus Ophidiomyces ophiodiicola is frequently associated with the skin lesions that are characteristic of SFD, but a causal relationship between the fungus and the disease has not been established. We experimentally infected captive-bred corn snakes (Pantherophis guttatus) in the laboratory with pure cultures of O. ophiodiicola. All snakes in the infected group (n = 8) developed gross and microscopic lesions identical to those observed in wild snakes with SFD; snakes in the control group (n = 7) did not develop skin infections. Furthermore, the same strain of O. ophiodiicola used to inoculate snakes was recovered from lesions of all animals in the infected group, but no fungi were isolated from individuals in the control group. Monitoring progression of lesions throughout the experiment captured a range of presentations of SFD that have been described in wild snakes. The host response to the infection included marked recruitment of granulocytes to sites of fungal invasion, increased frequency of molting, and abnormal behaviors, such as anorexia and resting in conspicuous areas of enclosures. While these responses may help snakes to fight infection, they could also impact host fitness and may contribute to mortality in wild snakes with chronic O. ophiodiicola infection. This work provides a basis for understanding the pathogenicity of O. ophiodiicola and the ecology of SFD by using a model system that incorporates a host species that is easy to procure and maintain in the laboratory.

  19. Behavioral and hormonal changes associated with the infective dose in experimental taeniasis in golden hamsters (Mesocricetus auratus).

    Science.gov (United States)

    Domínguez-Roldan, Rosa; Hallal-Calleros, Claudia; Sciutto, Edda; Hernández, Marisela; Aguirre-Flores, Virginio; García-Jiménez, Sara; Báez-Saldaña, Armida; Flores-Pérez, Fernando Iván

    2016-07-01

    It has been reported that behavioral changes relate to infection in different parasitoses. However, the relation between the extent of the behavioral changes and the magnitude of the infection has been scarcely studied. The aim of this study was to evaluate the relationship between different doses of infection and the behavioral changes induced in the experimental Taenia pisiformis taeniasis in golden hamsters. Groups of nine hamsters were infected with three or six T. pisiformis metacestodes. The locomotor activity was quantified daily in an open field test during the 21 days after infection; anxiety test was performed in an elevated plus-maze with a dark/light area at 7, 14 and 21 days post-infection, and serum cortisol levels were determined by radioimmunoassay before infection and at day 22 after infection. The challenge itself induced modifications on behavior and cortisol levels in hamsters, with or without successful infection (taenia development). Animals challenged with three metacestodes induced a decrease in locomotor activity and an increase in anxiety in infected animals. A higher and earlier decrease in locomotor activity and increased anxiety levels were observed in hamsters challenged with six cysticerci, which were accompanied by higher levels of sera cortisol at the end of the experiment. At necropsy, 44-55% of hamster became infected with an efficiency of implantation of 22-26%, challenged with three or six cysticerci respectively. The challenge of hamsters with metacestodes, promote behavioral changes in an extent dependent on the magnitude of the challenge, disregarding the effectiveness of the infection. Copyright © 2016 Elsevier Inc. All rights reserved.

  20. Influence of infection by Toxoplasma gondii on purine levels and E-ADA activity in the brain of mice experimentally infected mice.

    Science.gov (United States)

    Tonin, Alexandre A; Da Silva, Aleksandro S; Casali, Emerson A; Silveira, Stephanie S; Moritz, Cesar E J; Camillo, Giovana; Flores, Mariana M; Fighera, Rafael; Thomé, Gustavo R; Morsch, Vera M; Schetinger, Maria Rosa C; Rue, Mario De La; Vogel, Fernanda S F; Lopes, Sonia T A

    2014-07-01

    The aim of this study was to assess the purine levels and E-ADA activity in the brain of mice (BALB/c) experimentally infected with Toxoplasma gondii. In experiment I (n=24) the mice were infected with RH strain of T. gondii, while in experiment II (n=36) they were infected with strain ME-49 of T. gondii. Our results showed that, for RH strain (acute phase), an increase in both periods in the levels of ATP, ADP, AMP, adenosine, hypoxanthine, xanthine (only on day 6 PI) and uric acid (only on day 6 PI). By the other hand, the RH strain led, on days 4 and 6 PI, to a reduction in the concentration of inosine. ME-49, a cystogenic strain, showed some differences in acute and chronic phase, since on day 6 PI the levels of ATP and ADP were increased, while on day 30 these same nucleotides were reduced. On day 60 PI, ME-49 induced a reduction in the levels of ATP, ADP, AMP, adenosine, inosine and xanthine, while uric acid was increased. A decrease of E-ADA activity was observed in brain on days 4 and 6 PI (RH), and 30 PI (ME-49); however on day 60 PI E-ADA activity was increased for infection by ME-49 strain. Therefore, it was possible to conclude that infection with T. gondii changes the purine levels and the activity of E-ADA in brain, which may be associated with neurological signs commonly observed in this disease. Copyright © 2014 Elsevier Inc. All rights reserved.

  1. Vaccine-mediated immune responses to experimental pulmonary Cryptococcus gattii infection in mice.

    Directory of Open Access Journals (Sweden)

    Ashok K Chaturvedi

    Full Text Available Cryptococcus gattii is a fungal pathogen that can cause life-threatening respiratory and disseminated infections in immune-competent and immune-suppressed individuals. Currently, there are no standardized vaccines against cryptococcosis in humans, underlying an urgent need for effective therapies and/or vaccines. In this study, we evaluated the efficacy of intranasal immunization with C. gattii cell wall associated (CW and/or cytoplasmic (CP protein preparations to induce protection against experimental pulmonary C. gattii infection in mice. BALB/c mice immunized with C. gattii CW and/or CP protein preparations exhibited a significant reduction in pulmonary fungal burden and prolonged survival following pulmonary challenge with C. gattii. Protection was associated with significantly increased pro-inflammatory and Th1-type cytokine recall responses, in vitro and increased C. gattii-specific antibody production in immunized mice challenged with C. gattii. A number of immunodominant proteins were identified following immunoblot analysis of C. gattii CW and CP protein preparations using sera from immunized mice. Immunization with a combined CW and CP protein preparation resulted in an early increase in pulmonary T cell infiltrates following challenge with C. gattii. Overall, our studies show that C. gattii CW and CP protein preparations contain antigens that may be included in a subunit vaccine to induce prolonged protection against pulmonary C. gattii infection.

  2. Gag- and env-specific serum antibodies in cats after natural and experimental infection with feline immunodeficiency virus.

    NARCIS (Netherlands)

    G.F. Rimmelzwaan (Guus); C.H.J. Siebelink (Kees); H. Broos; G.A. Drost; K. Weijer (Kees); R. van Herwijnen (Rob); A.D.M.E. Osterhaus (Albert)

    1994-01-01

    textabstractIn order to monitor the antibody response to feline immunodeficiency virus (FIV) in cats, following experimental and natural infection, enzyme-linked immunosorbent assays (ELISAs) were developed using recombinant env and gag proteins and p24-specific monoclonal antibodies. It was shown

  3. Experimental infection of Pacific oyster Crassostrea gigas spat by ostreid herpesvirus 1: demonstration of oyster spat susceptibility

    Directory of Open Access Journals (Sweden)

    Schikorski David

    2011-02-01

    Full Text Available Abstract In 2008 and 2009, acute mortalities occurred in France among Pacific cupped oyster, Crassostrea gigas, spat. Different hypothesis including the implication of environmental factors, toxic algae and/or pathogens have been explored. Diagnostic tests indicated that OsHV-1 including a particular genotype, termed OsHV-1 μVar, was detected in most of samples and especially in moribund oysters with the highlighting of virus particles looking like herpes viruses by TEM examination. In this study, an experimental protocol to reproduce OsHV-1 infection in laboratory conditions was developed. This protocol was based on the intramuscular injection of filtered (0.22 μm tissue homogenates prepared from naturally OsHV-1 infected spat collected on French coasts during mortality outbreaks in 2008. Results of the experimental trials showed that mortalities were induced after injection. Moreover, filtered tissue homogenates induced mortalities whereas the same tissue homogenates exposed to an ultraviolet (UV treatment did not induce any mortality suggesting that oyster spat mortalities require the presence of a UV sensitive agent. Furthermore, analysis of injected oyster spat revealed the detection of high amounts of OsHV-1 DNA by real-time quantitative PCR. Finally, TEM analysis demonstrated the presence of herpes virus particles. The developed protocol allowed to maintain sources of infective virus which can be useful for the development of further studies concerning the transmission and the development of OsHV-1 infection.

  4. The effect of a fenbendazole treatment on cyst excretion and weight gain in calves experimentally infected with Giardia duodenalis.

    Science.gov (United States)

    Geurden, Thomas; Vandenhoute, Els; Pohle, Herbert; Casaert, Stijn; De Wilde, Nathalie; Vercruysse, Jozef; Claerebout, Edwin

    2010-04-19

    A total of 28 Holstein-Friesian calves were experimentally infected with 10(5)Giardia duodenalis cysts. Eleven days later, all animals were allocated into two groups of 14 animals each, based on the average pre-treatment cyst counts. Treatment was randomly assigned to one of the two groups, and all animals in the treatment group received a daily oral dosage of 15mg fenbendazole per kg bodyweight during 3 consecutive days. The calves in the control group received a placebo (water). From 3 days after treatment onwards, cyst excretion was determined three times a week during 4 consecutive weeks. The faecal consistency and general health were recorded on a daily basis, and all animals were weighed prior to treatment and weekly thereafter. At the end of the experimental period, there was a significant (Pfenbendazole treated and untreated calves experimentally infected with G. duodenalis, although additional data need to confirm the need for treatment in natural conditions.

  5. Experimental Mycoplasma gallisepticum infections in captive-reared wild turkeys

    Science.gov (United States)

    Rocke, Tonie E.; Yuill, Thomas M.; Amundson, Terry E.

    1988-01-01

    The effects of Mycoplasma gallisepticum (MG) infections on egg production, fertility, and hatchability were studied in captive-reared wild turkeys (Meleagris gallopavo). Three groups of adult birds, each consisting of four hens and two toms, were exposed to MG by the respiratory route at the beginning of their breeding season. Fourteen control birds received sterile growth medium. Although no mortality of infected or control birds occurred, egg production during the first breeding season after infection was reduced. The mean number of eggs/hen/day produced by infected groups the first breeding season postexposure (PE) was significantly lower than the control value. The mean number of eggs produced daily by the same hens 1 yr later was unaffected by MG infection. The pecentage of fertile eggs produced by infected groups was slightly reduced in both the first and second breeding seasons PE. Hatchability of fertile eggs from infected hens was significantly lower than eggs from control hens. Productivity may be impaired if MG infections occur in free-ranging wild turkey populations.

  6. Lactobacillus paracasei feeding improves the control of secondary experimental meningococcal infection in flu-infected mice.

    Science.gov (United States)

    Belkacem, Nouria; Bourdet-Sicard, Raphaëlle; Taha, Muhamed-Kkeir

    2018-04-10

    The use of probiotics to improve anti-microbial defence, such as for influenza infections, is increasingly recommended. However, no data are available on the effect of probiotics on flu-associated secondary bacterial infections. There is strong evidence of a spatiotemporal association between influenza virus infection and invasive Neisseria meningitidis. We thus investigated the effect of feeding mice Lactobacillus paracasei CNCM I-1518 in a mouse model of sequential influenza-meningococcal infection. We intranasally infected BALB/c mice with a strain of influenza A virus (IAV) H3N2 that was first adapted to mice. Seven days later, a secondary bacterial infection was induced by intranasal administration of bioluminescent N. meningitidis. During the experiment, mice orally received either L. paracasei CNCM I-1518 or PBS as a control. The effect of L. paracasei administration on secondary bacterial infection by N. meningitidis was evaluated. Oral consumption of L. paracasei CNCM I-1518 reduced the weight loss of infected mice and lowered the bioluminescent signal of infecting meningococci. This improvement was associated with higher recruitment of inflammatory myeloid cells, such as interstitial monocytes and dendritic cells, to the lungs. Our data highlight the role of the gut-lung axis. L. paracasei CNCM I-1518 may boost the defence against IAV infection and secondary bacterial infection, which should be further studied and validated in clinical trials.

  7. Experimental study of European bat lyssavirus type-2 infection in Daubenton's bats (Myotis daubentonii).

    Science.gov (United States)

    Johnson, Nicholas; Vos, Ad; Neubert, Larissa; Freuling, Conrad; Mansfield, Karen L; Kaipf, Ingrid; Denzinger, Annette; Hicks, Dan; Núñez, Alex; Franka, Richard; Rupprecht, Charles E; Müller, Thomas; Fooks, Anthony R

    2008-11-01

    European bat lyssavirus type 2 (EBLV-2) can be transmitted from Daubenton's bats to humans and cause rabies. EBLV-2 has been repeatedly isolated from Daubenton's bats in the UK but appears to be present at a low level within the native bat population. This has prompted us to investigate the disease in its natural host under experimental conditions, to assess its virulence, dissemination and likely means of transmission between insectivorous bats. With the exception of direct intracranial inoculation, only one of seven Daubenton's bats inoculated by subdermal inoculation became infected with EBLV-2. Both intramuscular and intranasal inoculation failed to infect the bats. No animal inoculated with EBLV-2 seroconverted during the study period. During infection, virus excretion in saliva (both viral RNA and live virus) was confirmed up to 3 days before the development of rabies. Disease was manifested as a gradual loss of weight prior to the development of paralysis and then death. The highest levels of virus were measured in the brain, with much lower levels of viral genomic RNA detected in the tongue, salivary glands, kidney, lung and heart. These observations are similar to those made in naturally infected Daubenton's bats and this is the first documented report of isolation of EBLV-2 in bat saliva. We conclude that EBLV-2 is most likely transmitted in saliva by a shallow bite.

  8. Efficacy of one dose vaccination against experimental infection with two Mycoplasma hyopneumoniae strains.

    Science.gov (United States)

    Michiels, Annelies; Arsenakis, Ioannis; Boyen, Filip; Krejci, Roman; Haesebrouck, Freddy; Maes, Dominiek

    2017-08-29

    Mycoplasma hyopneumoniae (M. hyopneumoniae) is the primary agent of enzootic pneumonia in pigs. Pigs are often infected with different M. hyopneumoniae strains. This study assessed the efficacy of vaccination against experimental infection with two genetically different M. hyopneumoniae strains in weaned piglets. At 33 days of age (D0), 45 M. hyopneumoniae-free piglets were randomly assigned to three different groups: 1) negative control group (NCG; n = 5): not vaccinated, not infected, 2) positive control group (PCG; n = 20): not vaccinated, infected, and 3) vaccination group (VG; n = 20): single vaccination with an inactivated whole-cell M. hyopneumoniae vaccine (Hyogen®, Ceva) (D1), infected. The PCG and VG were endotracheally inoculated with 7 × 10 7 CCU in 7 ml of the highly virulent M. hyopneumoniae strain F7.2C (D24) and 7 × 10 7 CCU in 7 ml low virulent strain F1.12A (D25). A respiratory disease score (RDS) was assessed from D24 until D53. At D53 (euthanasia), macroscopic lung lesions (MLL) were scored, log copies of M. hyopneumoniae DNA (qPCR) and IL-1 and IL-6-concentrations (ELISA) on bronchoalveolar lavage fluid were determined. The RDS and MLL at euthanasia were respectively 0, 1.20 and 0.55 (P hyopneumoniae strain as the vaccinated pigs coughed significantly less, and showed significantly less lung lesions compared to the non-vaccinated challenged pigs: the vaccinated animals showed a 52.9% lower RDS and 91.0% lower MLL compared to the PCG. In the bronchoalveolar lavage fluid collected at the necropsy of the vaccinated pigs, a significantly lower amount of M. hyopneumoniae-DNA and a significantly lower IL-1 and IL-6 concentration was found compared to the pigs of the PCG.

  9. Experimental infection of Aphanomyces invadans and susceptibility in seven species of tropical fish

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    Seyedeh F. Afzali

    2015-09-01

    Full Text Available Aim: Epizootic ulcerative syndrome (EUS causes by aquatic oomycete fungus, Aphanomyces invadans is a dangerous fish disease of a wide range of fresh and brackish water, wild and farmed fish throughout the world. The objective of the present study was to determine the susceptibility of a number of tropical fish species to the EUS and compare the severity of infection between experimental groups. Materials and Methods: Snakehead, Channa striata (Bloch, 1793; snakeskin gourami, Trichopodus pectoralis (Regan, 1910; koi carp, Cyprinus carpio (Linnaeus, 1758; broadhead catfish, Clarias macrocephalus (Günther, 1864; goldfish, Carassius auratus (Linnaeus, 1758; climbing perch, Anabas testudineus (Bloch, 1792; and Nile tilapia, Oreochromis niloticus (Linnaeus, 1758 were challenged by intramuscular injection using zoospores of Aphanomyces invadans (NJM9701. The infected fish skins and muscles were examined for EUS histopathological characteristics, and the results on the severity of lesions and mortality were analyzed using SPSS program. Results: All zoospore-injected fish were shown to be susceptible to the EUS infection except Nile tilapia. Although, the general histopathological pattern was similar in the zoospore-injected group, but there were some variation in granulomatous reaction, that is the presence or absence of giant cells, and time of mortality were detected. The result of statistical analysis showed that there was a significant difference between species, (c2=145.11 and p<0.01. Conclusion: Gourami, koi carp, and catfish were demonstrated to be highly susceptible while goldfish and climbing perch were found to be moderately susceptible to the EUS infection. These findings suggested that the cellular response of fish to mycotic infection and granulomatous reaction varied in different fish species, which could not be an indicator of susceptibility or resistant to the EUS itself, although it was shown that the granulation rate and the level of

  10. Tupaia belangeri as an experimental animal model for viral infection.

    Science.gov (United States)

    Tsukiyama-Kohara, Kyoko; Kohara, Michinori

    2014-01-01

    Tupaias, or tree shrews, are small mammals that are similar in appearance to squirrels. The morphological and behavioral characteristics of the group have been extensively characterized, and despite previously being classified as primates, recent studies have placed the group in its own family, the Tupaiidae. Genomic analysis has revealed that the genus Tupaia is closer to humans than it is to rodents. In addition, tupaias are susceptible to hepatitis B virus and hepatitis C virus. The only other experimental animal that has been demonstrated to be sensitive to both of these viruses is the chimpanzee, but restrictions on animal testing have meant that experiments using chimpanzees have become almost impossible. Consequently, the development of the tupaia for use as an animal infection model could become a powerful tool for hepatitis virus research and in preclinical studies on drug development.

  11. Biochemical studies in experimentally Escherichia coli infected broiler chicken supplemented with neem (Azadirachta indica leaf extract

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    Vikash Sharma

    2015-11-01

    Full Text Available Aim: An experimental study was conducted on 192-day-old broiler chicks for evaluating the effect of 10% neem leaf extract (NLE supplementationon biochemical parameters in chickens experimentally infected with Escherichia coli O78 at 107 CFU/0.5 ml at 7 days of age. Materials and Methods: The 192-day-old broiler chicks were procured. These chicks were divided into two groups (A and B containing 96 birds each on the 1st day. Diet of all the chicks of Group A was supplemented with 10%NLE in water, whereas chicks of Group B were given feed and water devoid of NLE supplementation throughout the experiment. After rearing for 1 week, chicks of both the groups (A and B were again divided into two subgroups (Group A into A1 and A2 and Group B into B1 and B2 of 54 and 42 birds, respectively. At the age of 7 days all the chicks of groups A1 and B1 were injected with E. coli O78 at 107 CFU/0.5 ml intraperitoneally. Blood samples were collected from six chicks from each group at day 0, 2, 4, 7, 14, 21, 28 days post-infection and serum was separated for biochemical studies. Results: There was a significant increase in serum alanine transaminase (ALT, aspartate transaminase (AST, lactate dehydrogenase (LDH activities, globulin concentration and a decrease in total protein (TP, albumin concentrations, and alkaline phosphatase (ALP activity in both the infected groups. However, the changes in biochemical values, i.e., ALT, AST, LDH, ALP, TP, albumin, and globulin wereof lower magnitude in NLE supplemented group suggesting hepatoprotective and cardioprotective effect of NLE. Conclusions: Fromthe present study, it is reasonable to conclude that significant increase in the value of ALT, AST, LDH, globulin, and significant decrease in the value of ALP, TP, and albumin was of lower magnitude in supplemented infected group (A1 as compared to non-supplemented infected group (B1 suggesting hepatoprotective and cardioprotective effect of NLE.

  12. Experimental infection of Balb/c nude mice with Hepatitis E virus

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    Zhu Jianguo

    2009-06-01

    Full Text Available Abstract Background Several animal species can reportedly act as reservoirs for Hepatitis E virus (HEV, a zoonotic pathogen. HEV and antibody to the virus have been detected in a variety of animals including rodents. Pig and rat models for HEV have been established for HEV, but a nude mouse has not yet been developed. Methods Balb/c nude mice were inoculated with swine HEV, both orally and via intravenous injection to insure infection. Negative control and experimental contact-exposed groups of mice were also included in the study. The liver, spleen, kidney, jejunum, ileum, cecum and colon of each mouse from all three groups were collected for reverse transcription nested polymerase chain reaction (RT-nPCR detection, indirect immunofluorescence observation and histopathologic examination. The sera from nude mice were tested for anti-HEV IgG by enzyme linked immunosorbent assay (ELISA. Activities of liver enzymes, including alanine aminotransferase (ALT, aspartate aminotransferase (AST and alkaline phosphatase (ALP, as well as total bilirubin (TBIL were also measured in the sera of the nude mice. Results HEV antigens and HEV RNA were detected in liver, spleen, kidney, jejunum, ileum and colon both by indirect immunofluorescence and by RT-nPCR in all of the inoculated and in one of the contact-exposed nude mice. Histopathological changes were observed in the liver and spleen of these mice. Infected mice showed increased levels of AST, ALP, and anti-HEV IgG in sera. The livers of contact-exposed mice showed obvious histopathological damage. Conclusion Nude mice could be readily infected by HEV isolated from pigs. The nude mouse may therefore be a useful animal model for studying the pathogenesis of HEV.

  13. Diagnostic performances of two rapid tests for detection of feline leukemia virus antigen in sera of experimentally feline leukemia virus-infected cats

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    Matthew R Krecic

    2017-12-01

    Full Text Available Objectives The objective of this study was to compare the diagnostic sensitivities and specificities of WITNESS FeLV-FIV (Zoetis and SNAP FIV/FeLV Combo Test (IDEXX for the detection of FeLV p27 antigen in the sera of experimentally feline leukemia virus (FeLV-infected cats. Methods Diagnostic sensitivities of WITNESS and SNAP were determined through testing of 47 serum samples collected from cats day 56 post-experimental infection with a virulent FeLV Rickard strain. Successful experimental infection was confirmed based on observation of FeLV antigen and proviral DNA in anti-coagulated (EDTA whole-blood samples by immunofluorescent antibody (IFA test and PCR, respectively. Diagnostic specificities of both tests were determined through testing of sera of 92 laboratory-housed, non-FeLV-exposed specific pathogen-free (SPF cats. Results Forty-one of 47 blood samples were IFA positive, whereas all 47 samples were PCR positive. All 92 non-FeLV-infected SPF cats were IFA and PCR negative. In comparison to IFA as the reference method, both WITNESS and SNAP tests yielded equivalent sensitivities and specificities of 100% and 97.8%, respectively. In comparison to PCR as the reference method, both WITNESS and SNAP tests likewise performed equivalently, with sensitivities and specificities of 91.5% and 100%, respectively. Conclusions and relevance Sensitivity and specificity of WITNESS FeLV-FIV for identifying FeLV p27 antigen in the sera of these experimentally FeLV-infected and non-FeLV-exposed SPF cats equaled those of the SNAP FIV/FeLV Combo Test. However, all positive results, regardless of the point-of-care test used, should be confirmed before making clinical decisions such as segregation from other cats or euthanasia.

  14. Temporal dynamics of 'HoBi'-like pestivirus quasispecies in persistently infected calves generated under experimental conditions.

    Science.gov (United States)

    Weber, Matheus N; Bauermann, Fernando V; Canal, Cláudio W; Bayles, Darrell O; Neill, John D; Ridpath, Julia F

    2017-01-02

    'HoBi'-like virus is an atypical group within the Pestivirus genus that is implicated in economic losses for cattle producers due to both acute and persistent infections. Pestivirus strains exist as quasispecies (swarms of individual viruses) in infected animals and the viral populations making up the quasispecies differ widely in size and diversity in each animal. In the present study the viral quasispecies circulating in persistently infected (PI) calves, generated and maintained under experimental conditions using two different 'HoBi'-like strains, was observed over time. An increase in genetic variability and the development of certain mutations was observed over time. Mutations observed included the loss of a putative N-linked glycosylation site in the E2 region and the change of specific residues in E1/E2. It is hypothesized that these changes may be the results on continued adaption of the pestivirus to individual hosts. This is the first study characterizing variation in the viral swarms of animals persistently infected with HoBi-like viruses over time. Studies of the shifts in PI viral swarms will contribute to our understanding of the host and viral mechanisms that function in the maintenance of pestivirus persistent infections. Published by Elsevier B.V.

  15. Pathogenesis and Immunohistochemical Studies of Caprine Pleuropneumonia in Experimentally Infected Goats

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    Umer Sadique*, Zafar Iqbal Chaudhry1, Muhammad Younus Rana2, Aftab Ahmad Anjum3, Zahoor-Ul-Hassan, Abdul Sajid and Muhammad Mushtaq

    2012-06-01

    Full Text Available This study was designed to evaluate the pathogenesis of caprine pleuropneumonia (CPP in the experimentally inoculated goats with Mycoplasma mycoides subspecies Capri (Mmc. For this purpose, 12 goats (Group B were inoculated with bacterial isolates of Mmc while four goats were kept as untreated control (Group A. Clinical signs of the disease were recorded twice daily. Two goats from group B were sacrificed on weekly basis to demonstrate gross pathological lesions in different organs. Tissue samples from lungs, trachea, liver, heart, kidney, spleen, and small intestines were preserved for histopathological studies. The lungs and lymph nodes were preserved to demonstrate the antigen in tissue by using immuno- histochemical technique. The disease was successfully reproduced in all infected goats with severe manifestation. The clinical signs and gross lesions of the disease were mild at the beginning and became severe at the third and fourth weeks and then progressed to moderate and chronic forms. The histopathological lesions characteristic of CPP were found in all the organs. Antigen of Mmc was detected in tissue sections of lungs and lymph nodes. In conclusion, the disease was efficiently reproduced in experimental animals that showed acute septicemic form with lethal outcome.

  16. Experimental Infection of Snakes with Ophidiomyces ophiodiicola Causes Pathological Changes That Typify Snake Fungal Disease.

    Science.gov (United States)

    Lorch, Jeffrey M; Lankton, Julia; Werner, Katrien; Falendysz, Elizabeth A; McCurley, Kevin; Blehert, David S

    2015-11-17

    Snake fungal disease (SFD) is an emerging skin infection of wild snakes in eastern North America. The fungus Ophidiomyces ophiodiicola is frequently associated with the skin lesions that are characteristic of SFD, but a causal relationship between the fungus and the disease has not been established. We experimentally infected captive-bred corn snakes (Pantherophis guttatus) in the laboratory with pure cultures of O. ophiodiicola. All snakes in the infected group (n = 8) developed gross and microscopic lesions identical to those observed in wild snakes with SFD; snakes in the control group (n = 7) did not develop skin infections. Furthermore, the same strain of O. ophiodiicola used to inoculate snakes was recovered from lesions of all animals in the infected group, but no fungi were isolated from individuals in the control group. Monitoring progression of lesions throughout the experiment captured a range of presentations of SFD that have been described in wild snakes. The host response to the infection included marked recruitment of granulocytes to sites of fungal invasion, increased frequency of molting, and abnormal behaviors, such as anorexia and resting in conspicuous areas of enclosures. While these responses may help snakes to fight infection, they could also impact host fitness and may contribute to mortality in wild snakes with chronic O. ophiodiicola infection. This work provides a basis for understanding the pathogenicity of O. ophiodiicola and the ecology of SFD by using a model system that incorporates a host species that is easy to procure and maintain in the laboratory. Skin infections in snakes, referred to as snake fungal disease (SFD), have been reported with increasing frequency in wild snakes in the eastern United States. While most of these infections are associated with the fungus Ophidiomyces ophiodiicola, there has been no conclusive evidence to implicate this fungus as a primary pathogen. Furthermore, it is not understood why the

  17. Evaluation of Nobuto filter paper strips for the detection of avian influenza virus antibody in waterfowl

    Science.gov (United States)

    Dusek, Robert J.; Hall, Jeffrey S.; Nashold, Sean W.; Teslaa, Joshua L.; Ip, Hon S.

    2011-01-01

    The utility of using Nobuto paper strips for the detection of avian influenza antibodies was examined in mallards (Anas platyrhynchos) experimentally infected with low pathogenic avian influenza viruses. Blood was collected 2 wk after infection and was preserved either as serum or whole blood absorbed onto Nobuto strips. Analysis of samples using a commercially available blocking enzyme-linked immunosorbent assay revealed comparable results (???96% sensitivity for all methods) between sera stored at -30 C and the Nobuto strip preservation method even when the Nobuto strips were stored up to 3 mo at room temperature (RT). Significant differences were detected in the ratio of sample absorbance to negative control absorbance for Nobuto strips stored at RT compared with sera stored at -30 C, although these differences did not affect the ability of the test to reliably detect positive and negative samples. Nobuto strips are a convenient and sensitive alternative to the collection of serum samples when maintaining appropriate storage temperatures is difficult. ?? 2011 American Association of Avian Pathologists.

  18. Cytokine, antibody and proliferative cellular responses elicited by Taenia solium calreticulin upon experimental infection in hamsters.

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    Fela Mendlovic

    Full Text Available Taenia solium causes two diseases in humans, cysticercosis and taeniosis. Tapeworm carriers are the main risk factor for neurocysticercosis. Limited information is available about the immune response elicited by the adult parasite, particularly the induction of Th2 responses, frequently associated to helminth infections. Calreticulin is a ubiquitous, multifunctional protein involved in cellular calcium homeostasis, which has been suggested to play a role in the regulation of immune responses. In this work, we assessed the effect of recombinant T. solium calreticulin (rTsCRT on the cytokine, humoral and cellular responses upon experimental infection in Syrian Golden hamsters (Mesocricetus auratus. Animals were infected with T. solium cysticerci and euthanized at different times after infection. Specific serum antibodies, proliferative responses in mesenteric lymph nodes and spleen cells, as well as cytokines messenger RNA (mRNA were analyzed. The results showed that one third of the infected animals elicited anti-rTsCRT IgG antibodies. Interestingly, mesenteric lymph node (MLN cells from either infected or non-infected animals did not proliferate upon in vitro stimulation with rTsCRT. Additionally, stimulation with a tapeworm crude extract resulted in increased expression of IL-4 and IL-5 mRNA. Upon stimulation, rTsCRT increased the expression levels of IL-10 in spleen and MLN cells from uninfected and infected hamsters. The results showed that rTsCRT favors a Th2-biased immune response characterized by the induction of IL-10 in mucosal and systemic lymphoid organs. Here we provide the first data on the cytokine, antibody and cellular responses to rTsCRT upon in vitro stimulation during taeniasis.

  19. Experimental study of action of autostrains Aerococcus viridans on the model Pseudomonas infection

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    D. O. Stepanskyi

    2017-05-01

    Full Text Available The paper presents the results of a study of the action of Aerococcus autostrains on the model of a chronic blue pus infection. For the study of the action of Aerococcus autosymbiont strains on Pseudomonas aeruginosa, three of the most biochemically and antagonistically active isolates were selected: 1 5m2015 (isolated from mice; 2 3k2015 (isolated from rats; 3 3ch2015 (isolated from humans. Experiments were conducted on 84 white outbred mice weighing 16–17 g, 60 were used as the experimental, and 24 as the control group. In the experimental group of animals, infected wounds were treated by Aerococcus autosymbiont strains once daily (0.2 billion ml–1 till recovery. The drug was administered under the scab with a syringe. In the control animals the wound was treated by isotonic sodium chloride solution (concentration 0.9% with the same route of administration and for the same period of time. It was found that from the very first days of application of Aerococci autosymbiont strains, perifocal inflammation was less severe in most animals in the research group compared with the control group. Starting from the fourth day of usage of Aerococcus autosymbiont strains the number of pseudomonades, contained in secretions from wounds in the experimental group of mice was significantly lower than in the control animals. It was revealed that in case of application of Aerococcus strain (5m2015 isolated from mice, the animals had better indicators of recovery, dynamics of local clinical signs of inflammation and the number of pseudomonades contained in the wound in comparison with other Aerococcus autostrains isolated from rats and humans. The wounds purified from pus and covered with dry scab faster. For example, wounds completely healed with dry scab rejection by the 11th day of observation in 44 of 58 surviving mice (75.9%. In the control group a similar pattern was observed in only 3 of 17 mice (17.6% by that period. The number of Pseudomonas

  20. Influence of experimental distemper infection on the distribution of lead in dogs previously subacutely intoxicated with lead carbonate

    Energy Technology Data Exchange (ETDEWEB)

    White, D.J.; Marshall, A.J.; McLeod, S.

    1975-01-01

    The ability of experimental canine distemper infection to mobilize body lead deposits has been studied in Beagle dogs previously subacutely intoxicated with lead carbonate. For comparative purposes dogs were included which had either received lead only or distemper only or remained undosed. It was found that in dogs predosed with lead, distemper infection resulted in a significant increase in lead levels in blood and urine; this coincided with the peak body temperatures reached on the third day post infection. It was also found that the lead content of the liver and bone of these dogs was considerably higher than that of dogs receiving lead alone; at the same time bone phosphorus showed a marked decrease while bone calcium values remained similar to undosed controls.

  1. DNA immunization against experimental genital herpes simplex virus infection.

    Science.gov (United States)

    Bourne, N; Stanberry, L R; Bernstein, D I; Lew, D

    1996-04-01

    A nucleic acid vaccine, expressing the gene encoding herpes simplex virus (HSV) type 2 glycoprotein D (gD2) under control of the cytomegalovirus immediate-early gene promoter, was used to immunize guinea pigs against genital HSV-2 infection. The vaccine elicited humoral immune responses comparable to those seen after HSV-2 infection. Immunized animals exhibited protection from primary genital HSV-2 disease with little or no development of vesicular skin lesions and significantly reduced HSV-2 replication in the genital tract. After recovery from primary infection, immunized guinea pigs experienced significantly fewer recurrences and had significantly less HSV-2 genomic DNA detected in the sacral dorsal root ganglia compared with control animals. Thus, immunization reduced the burden of latent infection resulting from intravaginal HSV-2 challenge, and a nucleic acid vaccine expressing the HSV-2 gD2 antigen protected guinea pigs against genital herpes, limiting primary infection and reducing the magnitude of latent infection and the frequency of recurrent disease.

  2. Sarcocystis neurona infections in raccoons (Procyon lotor): evidence for natural infection with sarcocysts, transmission of infection to opossums (Didelphis virginiana), and experimental induction of neurologic disease in raccoons.

    Science.gov (United States)

    Dubey, J P; Saville, W J; Stanek, J F; Lindsay, D S; Rosenthal, B M; Oglesbee, M J; Rosypal, A C; Njoku, C J; Stich, R W; Kwok, O C; Shen, S K; Hamir, A N; Reed, S M

    2001-10-24

    Equine protozoal myeloencephalitis (EPM) is a serious neurologic disease of horses in the Americas and Sarcocystis neurona is the most common etiologic agent. The distribution of S. neurona infections follows the geographical distributions of its definitive hosts, opossums (Didelphis virginiana, Didelphis albiventris). Recently, cats and skunks were reported as experimental and armadillos as natural intermediate hosts of S. neurona. In the present report, raccoons (Procyon lotor) were identified as a natural intermediate host of S. neurona. Two laboratory-raised opossums were found to shed S. neurona-like sporocysts after ingesting tongues of naturally-infected raccoons. Interferon-gamma gene knockout (KO) mice fed raccoon-opossum-derived sporocysts developed neurologic signs. S. neurona was identified immunohistochemically in tissues of KO mice fed sporocysts and the parasite was isolated in cell cultures inoculated with infected KO mouse tissues. The DNA obtained from the tongue of a naturally-infected raccoon, brains of KO mice that had neurological signs, and from the organisms recovered in cell cultures inoculated with brains of neurologic KO mice, corresponded to that of S. neurona. Two raccoons fed mature S. neurona sarcocysts did not shed sporocysts in their feces, indicating raccoons are not likely to be its definitive host. Two raccoons fed sporocysts from opossum feces developed clinical illness and S. neurona-associated encephalomyelitis was found in raccoons killed 14 and 22 days after feeding sporocysts; schizonts and merozoites were seen in encephalitic lesions.

  3. Improving Diagnosis and Treatment of Staphylococcus aureus Infections : Experimental Studies

    NARCIS (Netherlands)

    S. van den Berg (Sanne)

    2015-01-01

    markdownabstract__Abstract__ Staphylococcus aureus is an opportunistic pathogen that causes a variety of infections, ranging from mild skin infections like furuncles and impetigo, to severe, lifethreatening infections including endocarditis, osteomyelitis and pneumonia. Invasive infections are

  4. Humoral immunity through immunoglobulin M protects mice from an experimental actinomycetoma infection by Nocardia brasiliensis.

    Science.gov (United States)

    Salinas-Carmona, Mario C; Pérez-Rivera, Isabel

    2004-10-01

    An experimental model of infection with Nocardia brasiliensis, used as an example of a facultative intracellular pathogen, was tested. N. brasiliensis was injected into the rear foot pads of BALB/c mice to establish an infection. Within 30 days, infected animals developed a chronic actinomycetoma infection. Batch cultures of N. brasiliensis were used to purify P61, P38, and P24 antigens; P61 is a catalase, and P38 is a protease with strong caseinolytic activity. Active and passive immunizations of BALB/c mice with these three purified soluble antigens were studied. Protection was demonstrated for actively immunized mice. However, immunity lasted only 30 days. Other groups of immunized mice were bled at different times, and their sera were passively transferred to naive recipients that were then infected with N. brasiliensis. Sera collected 5, 6, and 7 days after donor immunization conferred complete, long-lasting protection. The protective effect of passive immunity decreased when sera were collected 2 weeks after donor immunization. However, neither the early sera (1-, 2-, and 3-day sera) nor the later sera (30- or 45-day sera) prevented the infection. Hyperimmune sera with the highest levels of immunoglobulin G (IgG) to N. brasiliensis antigens did not protect at all. The antigens tested induced two IgM peaks. The first peak was present 3 days after immunization but was not antigen specific and did not transfer protection. The second peak was evident 7 days after immunization, was an IgM response, was antigen specific, and conferred protection. This results clearly demonstrate that IgM antibodies protect the host against a facultative intracellular bacterium.

  5. Molecular identification of Heterakis spumosa obtained from brown rats (Rattus norvegicus) in Japan and its infectivity in experimental mice.

    Science.gov (United States)

    Šnábel, Viliam; Utsuki, Daisuke; Kato, Takehiro; Sunaga, Fujiko; Ooi, Hong-Kean; Gambetta, Barbara; Taira, Kensuke

    2014-09-01

    Heterakis spumosa is a nematode of invasive rodents, mainly affiliated with Rattus spp. of Asian origin. Despite the ecological importance and cosmopolitan distribution, little information is available on the genetic characteristics and infectivity to experimental animals of this roundworm. Heterakis isolates obtained from naturally infected brown rats caught in 2007 in the city of Sagamihara, east central Honshu, Japan, and maintained by laboratory passages were subjected to mitochondrial sequence analysis and experimental infection in mice. Sequencing of the cox1 gene revealed that nucleotides of H. spumosa and previously examined Heterakis isolonche isolates from gallinaceous birds in Japan differed by 11.2-12.2% that conforms to the range expected for interspecific differences. The two H. spumosa isolates differed by a single 138T/C non-synonymous substitution in the 393-bp mt sequence. In a dendrogram, the H. spumosa samples formed a subcluster with members of the nematode superfamily Heterakoidea, H. isolonche and Ascaridia galli. In an experimental infection study, ICR, AKR, B10.BR and C57BL/6 mice strains were inoculated with 200 H. spumosa eggs/head and necropsied at 14 and 90 days post-inoculation (DPI) when the number of worms was recorded. Eggs were initially detected in faeces from 32-35 DPI in ICR, AKR and B10.BR mice and the highest mean number of eggs per gram of faeces (EPG) was 4,800 at 38 DPI, 2,200 at 58 DPI and 800 at 44 and 72 DPI in ICR, AKR and B10.BR mice, respectively. No eggs were observed in faeces of the C57BL/6 mouse strain during the experiment. A similar number of juvenile worms were isolated from all mouse strains at 14 DPI, whereas no adult worms were detected in C57BL/6 mice at 90 DPI.

  6. Avian influenza in shorebirds: experimental infection of ruddy turnstones (Arenaria interpres) with avian influenza virus

    OpenAIRE

    Hall, Jeffrey S.; Krauss, Scott; Franson, J. Christian; TeSlaa, Joshua L.; Nashold, Sean W.; Stallknecht, David E.; Webby, Richard J.; Webster, Robert G.

    2012-01-01

    Please cite this paper as: Hall et al. (2012) Avian influenza in shorebirds: experimental infection of ruddy turnstones (Arenaria interpres) with avian influenza virus. Influenza and Other Respiratory Viruses DOI: 10.1111/j.1750‐2659.2012.00358.x. Background  Low pathogenic avian influenza viruses (LPAIV) have been reported in shorebirds, especially at Delaware Bay, USA, during spring migration. However, data on patterns of virus excretion, minimal infectious doses, and clinical outcome are l...

  7. Circulating and broncho-alveolar interleukin-6 in relation to body temperature in an experimental model of bovine Chlamydia psittaci infection.

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    Annette Prohl

    Full Text Available In rodent models of experimentally induced fever, the important role of interleukin-6 (IL-6 as a circulating endogenous pyrogen is well established. Studies employing larger animal species and real infections are scarce. Therefore, we assessed bioactive IL-6 in peripheral blood and in broncho-alveolar lavage fluid (BALF of calves after intra-bronchial inoculation with vital Chlamydia psittaci (Cp, with inactivated Cp, or with BGM cells. Only calves inoculated with vital Cp developed fever (peak at 2-3 days after challenge and significantly increased IL-6 activity. Controls inoculated with either inactivated Cp or BGM cells also expressed increased bioactive IL-6, but no fever developed. Activity of IL-6 in BALF was significantly higher compared to blood serum. This experimental model of Cp infection revealed no apparent relation between IL-6 in blood and body temperature, but did reveal a relation between IL-6 and other markers of inflammation in BALF. We conclude that a local inflammatory response in the lungs of infected calves caused fever, which developed by mechanisms including other mediators besides IL-6.

  8. Effect of Experimental Coccidiosis Infections on Body Weight Gain ...

    African Journals Online (AJOL)

    Infections with E. tenella in broiler breeder males showed that body weight gains of the uninfected males were significantly greater (p< 0.05) at 5, 7 and 14 days post inoculation (dpi) than those of the infected groups. Sperm productions at 0, 5 and 7 dpi (0=day of inoculation with infected oocysts) for the uninfected controls ...

  9. Detection and localization of rabbit hepatitis e virus and antigen in systemic tissues from experimentally intraperitoneally infected rabbits.

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    Jingjing Mao

    Full Text Available Rabbit hepatitis E virus (HEV is a novel genotype of HEV, and is considered to pose a risk of zoonotic transmission. Research into the systemic distribution of rabbit HEV in rabbits during different periods of infection has rarely been reported. To better understand this virus, we infected rabbits with second-passage rabbit HEV via an intraperitoneal route. After inoculation, the infection showed two types, temporary and constant infection. The detection of HEV RNA in the feces varied with time, and serum antigen correlated with fecal HEV RNA. Viremia only appeared 72 days after inoculation. The rabbits remained antibody negative throughout the experimental period. When HEV was localized, several organs besides the liver were HEV RNA positive. Tissue antigen was observed immunohistochemically in the different cells of various organs, especially in parts of the small intestine and the characteristic rabbit gut-associated lymphoid tissue. These data provide valuable information for future research into the pathogenesis of HEV.

  10. Monitoring Activity for Recognition of Illness in Experimentally Infected Weaned Piglets Using Received Signal Strength Indication ZigBee-based Wireless Acceleration Sensor

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    Sonia Tabasum Ahmed

    2016-01-01

    Full Text Available In this experiment, we proposed and implemented a disease forecasting system using a received signal strength indication ZigBee-based wireless network with a 3-axis acceleration sensor to detect illness at an early stage by monitoring movement of experimentally infected weaned piglets. Twenty seven piglets were divided into control, Salmonella enteritidis (SE infection, and Escherichia coli (EC infection group, and their movements were monitored for five days using wireless sensor nodes on their backs. Data generated showed the 3-axis movement of piglets (X-axis: left and right direction, Y-axis: anteroposterior direction, and Z-axis: up and down direction at five different time periods. Piglets in both infected groups had lower weight gain and feed intake, as well as higher feed conversion ratios than the control group (p<0.05. Infection with SE and EC resulted in reduced body temperature of the piglets at day 2, 4, and 5 (p<0.05. The early morning X-axis movement did not differ between groups; however, the Y-axis movement was higher in the EC group (day 1 and 2, and the Z-axis movement was higher in the EC (day 1 and SE group (day 4 during different experimental periods (p<0.05. The morning X and Y-axis movement did not differ between treatment groups. However, the Z-axis movement was higher in both infected groups at day 1 and lower at day 4 compared to the control (p<0.05. The midday X-axis movement was significantly lower in both infected groups (day 4 and 5 compared to the control (p<0.05, whereas the Y-axis movement did not differ. The Z-axis movement was highest in the SE group at day 1 and 2 and lower at day 4 and 5 (p<0.05. Evening X-axis movement was highest in the control group throughout the experimental period. During day 1 and 2, the Z-axis movement was higher in both of the infected groups; whereas it was lower in the SE group during day 3 and 4 (p<0.05. During day 1 and 2, the night X-axis movement was lower and the Z

  11. Efficacy of a Gal-lectin subunit vaccine against experimental Entamoeba histolytica infection and colitis in baboons (Papio sp.).

    Science.gov (United States)

    Abd Alla, Mohamed D; Wolf, Roman; White, Gary L; Kosanke, Stanley D; Cary, David; Verweij, Jaco J; Zhang, Mie-Jie; Ravdin, Jonathan I

    2012-04-26

    To determine the efficacy of a Gal-lectin based intranasal synthetic peptide vaccine, we developed a new experimental primate model of Entamoeba histolytica intestinal infection. Release of xenic E. histolytica trophozoites (5×10(6)) into the small bowel of baboons (Papio sp.) resulted in a rapid intestinal anti-amebic antibody response and a brief infection; however, release of trophozoites directly into the cecum (5 baboons) elicited a sustained E. histolytica infection, as determined by quantitative fecal PCR, and an ulcerative, inflammatory colitis observed on colonoscopy and histopathology. In three controlled experiments, baboons received four immunizations at seven day intervals of 1600 μg of the vaccine/nostril, with Cholera toxin, 20 μg/nostril as adjuvant; vaccinated (n=6) and control baboons (n=6) baboons were then challenged via colonoscopy with xenic trophozoites (5×10(6)). During 90 days of follow up, 250 of 415 (60.24%) fecal samples in control baboons had a (+) PCR for E. histolytica, compared to only 36 of 423 (8.51%) samples from vaccinated baboons (P<0.001). All 6 vaccinated baboons were free of infection by the 51st day after challenge, 5 of 6 controls positive had (+) fecal PCRs for up to 126 days post-challenge (P=0.019). Inflammatory colitis developed in 4 of 6 control baboons post-challenge, with invasive E. histolytica trophozoites present in 2 of the 4 on histopathology. There was no evidence of inflammatory colitis or parasite invasion in any of the vaccinated baboons; there was a strong inverse correlation between positive ELISA OD value indicating the presence of intestinal anti-peptide IgA antibodies and baboons having a positive fecal PCR CT value, P<0.001. In conclusion, we developed a novel primate model of E. histolytica intestinal infection and demonstrated that a Gal-lectin-based intranasal synthetic peptide vaccine was highly efficacious in preventing experimental E. histolytica infection and colitis in baboons. Copyright

  12. Experimental Pseudomonas anguilliseptica infection in turbot Psetta maxima (L.: a histopathological and immunohistochemical study

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    JL Romalde

    2009-06-01

    Full Text Available Experimental infection with Pseudomonas anguilliseptica was performed both by intraperitoneal (i.p. and bath route on juvenile turbot (Psetta maxima in order to evaluate the pathology induced. Turbot was found to be sensitive to i.p. challenge (1.7x106 CFU/fish but no to bath exposure. The i.p. challenge induced septicaemic infection and mortality. Externally, moribund fish showed distended abdomen and pale areas at day 9. The gross pathological internal signs present were abundant ascitic fluid in the peritoneal cavity, pale and enlarged spleen, pale and friable liver, and congestive and dilated gut with yellowish exudates. On histopathological examination, bacterial invasion was common in all the tissues studied but the most prominent pathological changes were observed in gut, spleen and kidney after 7 day with features of necrosis. The immunohistochemical findings support the widespread localization of the bacteria after the i.p. injection since the P. anguilliseptica was detected in spleen from day 1 post injection, in liver, kidney and gut from day 4, in muscle from day 7 and in brain from day 9. The difficulties in infecting healthy fish by bath challenge can be explained by the opportunistic nature of this pathogen.

  13. Experimental infection with the Toxoplasma gondii ME-49 strain in the Brazilian BR-1 mini pig is a suitable animal model for human toxoplasmosis

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    Farlen José Bebber Miranda

    2015-02-01

    Full Text Available Toxoplasma gondii causes toxoplasmosis, a worldwide disease. Experimentation with pigs is necessary for the development of new therapeutic approaches to human diseases. BR-1 mini pigs were intramuscularly infected with T. gondii with tachyzoites (RH strain or orally infected with cysts (ME-49 strain. Haematology and serum biochemistry were analysed and buffy coat cells were inoculated in mice to determine tachyzoite circulation. No alterations were observed in erythrocyte and platelet values; however, band neutrophils increased seven days after infection with ME-49. Serology of the mice inoculated with pig blood leucocytes revealed circulating ME-49 or RH strain tachyzoites in the pigs' peripheral blood at two and seven or nine days post-infection. The tachyzoites were also directly observed in blood smears from the infected pigs outside and inside leucocytes for longer periods. Alanine-aminotransferase was high at days 21 and 32 in the RH infected pigs. After 90 days, the pigs were euthanised and their tissue samples were processed and inoculated into mice. The mice serology revealed the presence of parasites in the hearts, ileums and mesenteric lymph nodes of the pigs. Additionally, cysts in the mice were only observed after pig heart tissue inoculation. The infected pigs presented similar human outcomes with relatively low pathogenicity and the BR-1 mini pig model infected with ME-49 is suitable to monitor experimental toxoplasmosis.

  14. Experimental Infection of Rhodnius prolixus (Hemiptera, Triatominae with Mycobacterium leprae Indicates Potential for Leprosy Transmission.

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    Arthur da Silva Neumann

    Full Text Available Leprosy is a chronic dermato-neurological disease caused by infection with Mycobacterium leprae. In 2013 almost 200,000 new cases of leprosy were detected around the world. Since the first symptoms take from years to decades to appear, the total number of asymptomatic patients is impossible to predict. Although leprosy is one of the oldest records of human disease, the mechanisms involved with its transmission and epidemiology are still not completely understood. In the present work, we experimentally investigated the hypothesis that the mosquitoes Aedes aegypti and Culex quinquefasciatus and the hemiptera Rhodnius prolixus act as leprosy vectors. By means of real-time PCR quantification of M. leprae 16SrRNA, we found that M. leprae remained viable inside the digestive tract of Rhodnius prolixus for 20 days after oral infection. In contrast, in the gut of both mosquito species tested, we were not able to detect M. leprae RNA after a similar period of time. Inside the kissing bug Rhodnius prolixus digestive tract, M. leprae was initially restricted to the anterior midgut, but gradually moved towards the hindgut, in a time course reminiscent of the life cycle of Trypanosoma cruzi, a well-known pathogen transmitted by this insect. The maintenance of M. leprae infectivity inside the digestive tract of this kissing bug is further supported by successful mice footpad inoculation with feces collected 20 days after infection. We conclude that Rhodnius prolixus defecate infective M. leprae, justifying the evaluation of the presence of M. leprae among sylvatic and domestic kissing bugs in countries endemic for leprosy.

  15. Experimental Infection of Rhodnius prolixus (Hemiptera, Triatominae) with Mycobacterium leprae Indicates Potential for Leprosy Transmission.

    Science.gov (United States)

    Neumann, Arthur da Silva; Dias, Felipe de Almeida; Ferreira, Jéssica da Silva; Fontes, Amanda Nogueira Brum; Rosa, Patricia Sammarco; Macedo, Rafael Enrique; Oliveira, José Henrique; Teixeira, Raquel Lima de Figueiredo; Pessolani, Maria Cristina Vidal; Moraes, Milton Ozório; Suffys, Philip Noel; Oliveira, Pedro L; Sorgine, Marcos Henrique Ferreira; Lara, Flavio Alves

    2016-01-01

    Leprosy is a chronic dermato-neurological disease caused by infection with Mycobacterium leprae. In 2013 almost 200,000 new cases of leprosy were detected around the world. Since the first symptoms take from years to decades to appear, the total number of asymptomatic patients is impossible to predict. Although leprosy is one of the oldest records of human disease, the mechanisms involved with its transmission and epidemiology are still not completely understood. In the present work, we experimentally investigated the hypothesis that the mosquitoes Aedes aegypti and Culex quinquefasciatus and the hemiptera Rhodnius prolixus act as leprosy vectors. By means of real-time PCR quantification of M. leprae 16SrRNA, we found that M. leprae remained viable inside the digestive tract of Rhodnius prolixus for 20 days after oral infection. In contrast, in the gut of both mosquito species tested, we were not able to detect M. leprae RNA after a similar period of time. Inside the kissing bug Rhodnius prolixus digestive tract, M. leprae was initially restricted to the anterior midgut, but gradually moved towards the hindgut, in a time course reminiscent of the life cycle of Trypanosoma cruzi, a well-known pathogen transmitted by this insect. The maintenance of M. leprae infectivity inside the digestive tract of this kissing bug is further supported by successful mice footpad inoculation with feces collected 20 days after infection. We conclude that Rhodnius prolixus defecate infective M. leprae, justifying the evaluation of the presence of M. leprae among sylvatic and domestic kissing bugs in countries endemic for leprosy.

  16. Detection of arboviruses and other micro-organisms in experimentally infected mosquitoes using massively parallel sequencing.

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    Sonja Hall-Mendelin

    Full Text Available Human disease incidence attributed to arbovirus infection is increasing throughout the world, with effective control interventions limited by issues of sustainability, insecticide resistance and the lack of effective vaccines. Several promising control strategies are currently under development, such as the release of mosquitoes trans-infected with virus-blocking Wolbachia bacteria. Implementation of any control program is dependent on effective virus surveillance and a thorough understanding of virus-vector interactions. Massively parallel sequencing has enormous potential for providing comprehensive genomic information that can be used to assess many aspects of arbovirus ecology, as well as to evaluate novel control strategies. To demonstrate proof-of-principle, we analyzed Aedes aegypti or Aedes albopictus experimentally infected with dengue, yellow fever or chikungunya viruses. Random amplification was used to prepare sufficient template for sequencing on the Personal Genome Machine. Viral sequences were present in all infected mosquitoes. In addition, in most cases, we were also able to identify the mosquito species and mosquito micro-organisms, including the bacterial endosymbiont Wolbachia. Importantly, naturally occurring Wolbachia strains could be differentiated from strains that had been trans-infected into the mosquito. The method allowed us to assemble near full-length viral genomes and detect other micro-organisms without prior sequence knowledge, in a single reaction. This is a step toward the application of massively parallel sequencing as an arbovirus surveillance tool. It has the potential to provide insight into virus transmission dynamics, and has applicability to the post-release monitoring of Wolbachia in mosquito populations.

  17. Annual cycle of plasma luteinizing hormone and sex hormones in male and female mallards (Anas platyrhynchos)

    Science.gov (United States)

    Donham, R.S.

    1979-01-01

    Comparisons between 'wild'and 'game farm' mallards (Anas platyrhynchos) were made to assess the differences in the temporal changes of plasma hormones. Seasonal variation in the levels of immunoreactive luteinizing hormone (LH), testosterone, 5 -dihydrotestosterone (DHT), estrone, estradiol-17i?? and progesterone were measured in male and female mallards. In all birds there was a vernal increase in the concentrations of LH and testosterone in plasma which were correlated with the development of the testes and ovaries prior to and during the nesting season. The concentrations of estrogens in the plasma of the females were, in general, slightly higher during the nesting season but were much lower than the levels of testosterone. The highest levels of LH and testosterone in the females coincided precisely with the period of egg laying which occurred approximately one month earlier in game farm females than in wild females. The concentrations of LH and testosterone in the plasma of females decreased rapidly during incubation. In wild males, the decline in levels of these hormones temporally coincided with that of females. In contrast, plasma levels of LH and testosterone of males of the game farm stock remained elevated after the beginning of incubation in females to which they were paired. On the basis of these results and an examination of the literature, it appears that domestication results in: 1) increased reproductive potential through earlier initiation of nesting and by delay of the termination of reproduction until later in the summer; and 2) a decrease in the synchronization of the hormonal events supporting reproduction between the male and female of a pair. Testicular weights and plasma levels of testosterone become higher in game farm and domestic males than in the wild stock but levels of LH are similar.

  18. Efficacy of a 60Co irradiated vaccine for experimentally infected calves with dictyocaulus viviparus

    International Nuclear Information System (INIS)

    Zurita, Edgar; Paredes, Julio; Fernandez, Ardey

    1991-01-01

    Dictyocaulus viviparus larvae in non-infected stage (L.1) were cultured in vitro to their infective stage (L.3) and were irradiated with 40 Krad from 6 0 C o and used as a vaccine. The oral experimental vaccine dose was 1000 L.3/animal. Three groups were formed with 8 calves in each one: group No. 1 and group No. 2 were vaccinated at 10 weeks of age. Four weeks later group No. 1 was infected with non-irradiated 60 L.3/Kg. of animal weight 'challenge dose'. After four weeks of post-vaccination group No. 2 was revaccinated and 4 weeks later it was infected with the 'challenge dose' as the previous group. Eight calves constituted group No. 3, four in each group; they were infected with only the challenge dose respectively. Information data on respiratory and cardiac frequency, temperature, weight, and L.1 count/g. of feces were obtained from each animal three times a week. After five weeks of post-challenge all animals were slaughtered to observe anatomopathologic lessions in the heart and lungs; the number of adult Dictyocaulus viviparus present in the respiratory tract were search 't'. Student test was used for the statistical analysis. The weight increment difference between animals of group No. 1 related control group was 7Kg.; and 11.25 Kg/animal in group No. 2 respectively. The percentage of protection confered by the vaccine to the subjects in group No. 1 relative to the respectivecontrol group, was 83.2; that for the group No. 2 was 88.5 per cent. Post-morten examination revealed severe anatomopathologic lessions in the control groups; only few lessions were observed in group No. 1 and practically none in group No. 2

  19. Cis and trans acting factors involved in human cytomegalovirus experimental and natural latent infection of CD14 (+ monocytes and CD34 (+ cells.

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    Cyprian C Rossetto

    Full Text Available The parameters involved in human cytomegalovirus (HCMV latent infection in CD14 (+ and CD34 (+ cells remain poorly identified. Using next generation sequencing we deduced the transcriptome of HCMV latently infected CD14 (+ and CD34 (+ cells in experimental as well as natural latency settings. The gene expression profile from natural infection in HCMV seropositive donors closely matched experimental latency models, and included two long non-coding RNAs (lncRNAs, RNA4.9 and RNA2.7 as well as the mRNAs encoding replication factors UL84 and UL44. Chromatin immunoprecipitation assays on experimentally infected CD14 (+ monocytes followed by next generation sequencing (ChIP-Seq were employed to demonstrate both UL84 and UL44 proteins interacted with the latent viral genome and overlapped at 5 of the 8 loci identified. RNA4.9 interacts with components of the polycomb repression complex (PRC as well as with the MIE promoter region where the enrichment of the repressive H3K27me3 mark suggests that this lncRNA represses transcription. Formaldehyde Assisted Isolation of Regulatory Elements (FAIRE, which identifies nucleosome-depleted viral DNA, was used to confirm that latent mRNAs were associated with actively transcribed, FAIRE analysis also showed that the terminal repeat (TR region of the latent viral genome is depleted of nucleosomes suggesting that this region may contain an element mediating viral genome maintenance. ChIP assays show that the viral TR region interacts with factors associated with the pre replication complex and a plasmid subclone containing the HCMV TR element persisted in latently infected CD14 (+ monocytes, strongly suggesting that the TR region mediates viral chromosome maintenance.

  20. Efficacy of the amino-acetonitrile derivative, monepantel, against experimental and natural adult stage gastro-intestinal nematode infections in sheep.

    Science.gov (United States)

    Sager, Heinz; Hosking, Barry; Bapst, Béatrice; Stein, Philip; Vanhoff, Kathleen; Kaminsky, Ronald

    2009-01-22

    Multiple drug resistance by nematodes, against anthelmintics has become an important economic problem in sheep farming worldwide. Here we describe the efficacy of monepantel, a developmental molecule from the recently discovered anthelmintic class, the amino-acetonitrile derivatives (AADs). Efficacy was tested against adult stage gastro-intestinal nematodes (GINs) in experimentally and naturally infected sheep at a dose of 2.5mg/kg body weight when administered as an oral solution. Some of the isolates used in experimental infection studies were known to be resistant to the benzimidazoles or levamisole anthelmintics; strains resistant to the macrocyclic lactones were not available for these tests. Worm count-based efficacies of >98% were determined in these studies. As an exception, Oesophagostomum venulosum was only reduced by 88% in one study, albeit with a low worm burden in the untreated controls (geometric mean 15.4 worms). Similar efficacies for monepantel were also confirmed in naturally infected sheep. While the efficacy against most species was >99%, the least susceptible species was identified as Nematodirus spathiger, and although efficacy was 92.4% in one study it was generally >99%. Several animals were infected with Trichuris ovis, which was not eliminated after the treatment. Monepantel demonstrated high activity against a broad range of the important GINs of sheep, which makes this molecule an interesting candidate for use in this species, particularly in regions with problems of anthelmintic resistance. Monepantel was well tolerated by the treated sheep, with no treatment related adverse events documented.

  1. Antimicrobial susceptibility of Brachyspira spp. isolated from commercial laying hens and free-living wild mallards (Anas platyrhynchos).

    Science.gov (United States)

    Jansson, Désirée S; Pringle, Märit

    2011-08-01

    In vitro antimicrobial susceptibility to tylosin, valnemulin, tiamulin, doxycycline, lincomycin and ampicillin was investigated by broth dilution in 48 Brachyspira spp. isolates from commercial laying hens (n=30) and free-living wild mallards (Anas platyrhynchos) (n=18). Presumed pathogens (Brachyspira alvinipulli, Brachyspira intermedia, Brachyspira pilosicoli), commensals (Brachyspira murdochii, Brachyspira innocens, "Brachyspira pulli"), and isolates of undetermined species affiliation were included. The laying hens had not been exposed to therapeutic levels of antimicrobials for at least 50 weeks before sampling, and low levels of environmental antimicrobial exposure were presumed in mallards. No isolates with decreased susceptibility to tylosin, valnemulin, tiamulin or doxycycline were found. Decreased susceptibility to lincomycin (minimum inhibitory concentration 16 µg/ml) was detected in two isolates (Brachyspira sp.) from laying hens. Five isolates showed decreased susceptibility to ampicillin (minimum inhibitory concentration 16 to >32 µg/ml), including two "B. pulli" and one B. alvinipulli from laying hens, and isolates of B. pilosicoli and "B. pulli" from mallards. Decreased susceptibility to ampicillin was associated with β-lactamase activity in four isolates. A new variant of a class D β-lactamase gene designated bla (oxa-192) was identified in a B. pilosicoli isolate of mallard origin. This is the first time the genetic basis for antimicrobial resistance is described in Brachyspira spp. from a free-living wild bird. Isolates displaying decreased susceptibility to ampicillin were accompanied by fully susceptible isolates of the same species or other genotypes within three laying hen flocks. This underlines the need for performing antimicrobial susceptibility tests on single clones/genotypes, and to analyse multiple isolates from the same flock.

  2. Ivermectin: activity against larval Strongylus vulgaris and adult Trichostrongylus axei in experimental infections in ponies.

    Science.gov (United States)

    Lyons, E T; Drudge, J H; Tolliver, S C

    1982-08-01

    Activity of ivermectin, administered IM at the dosage rate of 200 micrograms/kg of body weight, was evaluated in controlled tests against migrating larvae of Strongylus vulgaris and adult Trichostrongylus axei in experimental infections in 6 ponies raised worm-free. Ponies were given 2,190 or 2,400 infective 3rd-stage larvae of S vulgaris at 7 days before treatment and 22,000 or 22,750 infective 3rd-stage larvae of T axei at 42 or 45 days before treatment. Three ponies were given ivermectin plus vehicle, and 3 ponies were given the vehicle only; the ponies were euthanatized 7 or 9 days after treatment. At necropsy, 4th-stage S vulgaris larvae were not recovered from visceral arteries of the 3 ivermectin plus vehicle-treated ponies, but 21 to 40 larvae were recovered from each of the 3 vehicle-treated ponies. Also at necropsy, adult T axei (140 specimens) were recovered from only 1 ot the 3 ivermectin plus vehicle-treated ponies, but 4,610 to 6,410 specimens were found in each of the 3 vehicle-treated ponies. Toxicosis was not observed after treatment.

  3. Experimental Cowpox Virus (CPXV) Infections of Bank Voles: Exceptional Clinical Resistance and Variable Reservoir Competence.

    Science.gov (United States)

    Franke, Annika; Ulrich, Rainer G; Weber, Saskia; Osterrieder, Nikolaus; Keller, Markus; Hoffmann, Donata; Beer, Martin

    2017-12-19

    Cowpox virus (CPXV) is a zoonotic virus and endemic in wild rodent populations in Eurasia. Serological surveys in Europe have reported high prevalence in different vole and mouse species. Here, we report on experimental CPXV infections of bank voles ( Myodes glareolus ) from different evolutionary lineages with a spectrum of CPXV strains. All bank voles, independently of lineage, sex and age, were resistant to clinical signs following CPXV inoculation, and no virus shedding was detected in nasal or buccal swabs. In-contact control animals became only rarely infected. However, depending on the CPXV strain used, inoculated animals seroconverted and viral DNA could be detected preferentially in the upper respiratory tract. The highest antibody titers and virus DNA loads in the lungs were detected after inoculation with two strains from Britain and Finland. We conclude from our experiments that the role of bank voles as an efficient and exclusive CPXV reservoir seems questionable, and that CPXV may be maintained in most regions by other hosts, including other vole species. Further investigations are needed to identify factors that allow and modulate CPXV maintenance in bank voles and other potential reservoirs, which may also influence spill-over infections to accidental hosts.

  4. IL-6 is Upregulated in Late-Stage Disease in Monkeys Experimentally Infected with Trypanosoma brucei rhodesiense

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    Dawn Nyawira Maranga

    2013-01-01

    Full Text Available The management of human African trypanosomiasis (HAT is constrained by lack of simple-to-use diagnostic, staging, and treatment tools. The search for novel biomarkers is, therefore, essential in the fight against HAT. The current study aimed at investigating the potential of IL-6 as an adjunct parameter for HAT stage determination in vervet monkey model. Four adult vervet monkeys (Chlorocebus aethiops were experimentally infected with Trypanosoma brucei rhodesiense and treated subcuratively at 28 days after infection (dpi to induce late stage disease. Three noninfected monkeys formed the control group. Cerebrospinal fluid (CSF and blood samples were obtained at weekly intervals and assessed for various biological parameters. A typical HAT-like infection was observed. The late stage was characterized by significant (P<0.05 elevation of CSF IL-6, white blood cell count, and total protein starting 35 dpi with peak levels of these parameters coinciding with relapse parasitaemia. Brain immunohistochemical staining revealed an increase in brain glial fibrillary acidic protein expression indicative of reactive astrogliosis in infected animals which were euthanized in late-stage disease. The elevation of IL-6 in CSF which accompanied other HAT biomarkers indicates onset of parasite neuroinvasion and show potential for use as an adjunct late-stage disease biomarker in the Rhodesian sleeping sickness.

  5. Avian influenza in shorebirds: experimental infection of ruddy turnstones (Arenaria interpres) with avian influenza virus

    Science.gov (United States)

    Hall, Jeffrey S.; Krauss, Scott; Franson, J. Christian; TeSlaa, Joshua L.; Nashold, Sean W.; Stallknecht, David E.; Webby, Richard J.; Webster, Robert G.

    2013-01-01

    Background: Low pathogenic avian influenza viruses (LPAIV) have been reported in shorebirds, especially at Delaware Bay, USA, during spring migration. However, data on patterns of virus excretion, minimal infectious doses, and clinical outcome are lacking. The ruddy turnstone (Arenaria interpres) is the shorebird species with the highest prevalence of influenza virus at Delaware Bay. Objectives: The primary objective of this study was to experimentally assess the patterns of influenza virus excretion, minimal infectious doses, and clinical outcome in ruddy turnstones. Methods: We experimentally challenged ruddy turnstones using a common LPAIV shorebird isolate, an LPAIV waterfowl isolate, or a highly pathogenic H5N1 avian influenza virus. Cloacal and oral swabs and sera were analyzed from each bird. Results: Most ruddy turnstones had pre-existing antibodies to avian influenza virus, and many were infected at the time of capture. The infectious doses for each challenge virus were similar (103·6–104·16 EID50), regardless of exposure history. All infected birds excreted similar amounts of virus and showed no clinical signs of disease or mortality. Influenza A-specific antibodies remained detectable for at least 2 months after inoculation. Conclusions: These results provide a reference for interpretation of surveillance data, modeling, and predicting the risks of avian influenza transmission and movement in these important hosts.

  6. Experimental infection of octopus vulgaris (Cuvier, 1797) with Photobacterium damsela subsp. piscicida. Immunohistochemical tracking of antigen and tissue responses.

    Science.gov (United States)

    Bakopoulos, Vasileios; White, Daniella; Valsamidis, Michail-Aggelos; Vasilaki, Feli

    2017-03-01

    Adult common octopus individuals were intramuscularly infected with Photobacterium damsela subsp. piscicida in order to investigate if this species is sensitive to this common and important fish pathogen. The fate of the bacterial antigens and the tissue responses of Octopus vulgaris were studied employing immunohistochemical techniques. Strong reaction at the site of injection was evident from day 2 post-infection that continued until day 14. Great numbers of hemocytes that were attracted at the site of infection were involved in phagocytosis of bacteria. Very early in the infection, a transition of cells to fibroblasts and an effort to isolate the infection was observed. During the course of the study, very large necrotic cells were seen at the site of infection, whereas during the later stages hemocytes with phagocytosed bacteria were observed in well-defined pockets inside the muscle tissue. None of the internal organs tested for the presence of the bacterium were positive with the exception of the digestive gland where antigen staining was observed which was not associated with hemocyte infiltration. The high doses of bacterial cells used in this experimental infection and the lack of disease signs from Octopus vulgaris suggest that, under normal conditions, octopus is resistant to Photobacterium damsela subsp. piscicida. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. Experimental intraocular infection of exotic cockerels with field strain of velogenic Newcastle disease virus in Nigeria

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    Samaila Jonathan Badau

    2015-12-01

    Full Text Available Experimental intraocular (conjunctival infection of exotic cockerels with a new field strain of viscerotropic velogenic Newcastle Disease Virus (NDV was conducted to explore the concurrence of some pathological changes with humoral immune responses. After the NDV infection of 4-week-old cockerels, pathologic changes and antibody responses were observed. The clinical signs observed after the artificial inoculation included inappetence, depression, diarrhea, dyspnea, wing and leg paralysis, torticollis and weight loss. Morbidity due to the NDV was 100%, but mortality was 80% by day 18-21 post-infection. Early hyperthermia followed by terminal hypothermia, decreased packed cell volume (PCV, and 231.4 folds peak-antibody response were observed. Necrotic and/or inflammatory lesions were present in the proventriculus, intestine, liver, spleen, kidney and brain. Neurologic and digestive tract perturbations occurred in 10% and 85% of cases, respectively. The disease consistently caused stunted growth, decreased PCV, and necro-inflammatroy lesions concurrent with antibody response, suggesting probable involvement of immune-mediated mechanisms and cell membrane desialylation by viral neuraminidase in the pathogenesis.

  8. Neither hippurate-negative Brachyspira pilosicoli nor Brachyspira pilosicoli type strain caused diarrhoea in early-weaned pigs by experimental infection

    DEFF Research Database (Denmark)

    Fossi, M.; Ahlsten, K.; Pohjanvirta, T.

    2005-01-01

    Fossi M, Ahlsten K, Pohjanvirta T, Anttila M, Kokkonen T, Jensen TK, Boye M, Sukura A, Pelkola K, Pelkonen S: Neither hippurate-negative Brachyspira pilosicoli nor Brachyspira pilosicoli type strain caused diarrhoea in early-weaned pigs by experimental infection. Acta vet. scand. 2005, 46, 257...

  9. Changes in blood sugar levels of rats experimentally infected with Trypanosoma brucei and treated with imidocarb dipropionate and diminazene aceturate

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    Nwoha Rosemary Ijeoma Ogechi

    2016-01-01

    Full Text Available Objective: To determine the effect of Trypanosoma brucei (T. brucei on blood sugar level of infected rats. Methods: The experiment was done with 42 albino rats grouped into 3 groups of 14 members each. Group A was uninfected (control group, Group B was infected with T. brucei and treated with diminazene aceturate, and Group C was infected with T. brucei and treated with imidocarb dipropionate. Blood samples were collected from the media canthus of the experimental rats on Days 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 for the assessment of change in blood sugar levels. The blood sugar levels were determined with a glucometer (Accu-chek active serial No. GN: 10023338. Results: By 4 to 5 days post infection, there was a significant increase (P 0.05 was observed in the groups when compared with the control group till Day 12 of the experiment. Conclusions: T. brucei caused a significant increase in blood sugar of infected rats.

  10. Increased pulmonary secretion of tumor necrosis factor-alpha in calves experimentally infected with bovine respiratory syncytial virus

    DEFF Research Database (Denmark)

    Rontved, C. M.; Tjørnehøj, Kirsten; Viuff, B.

    2000-01-01

    , of which 23 were experimentally infected with BRSV and five were given a mock inoculum. The presence of the cytokine tumor necrosis factor alpha (TNF-alpha) in the BAL fluids was detected and quantified by a capture ELISA. TNF-alpha was detected in 21 of the infected animals. The amount of TNF-alpha...... in the BAL fluid of calves killed post inoculation day (PID) 2 and 4 was at the same very low level as in the uninfected control animals. Large amounts of TNF-alpha were detected on PID 6, maximum levels of TNF-alpha were reached on PID 7, and smaller amounts of TNF-alpha were seen on PID 8. The high levels...... of TNF-alpha appeared on the days where severe lung lesions and clinical signs were obvious and the amounts of BRSV-antigen were at their greatest. Although Pasteurellaceae were isolated from some of the BRSV-infected calves, calves treated with antibiotics before and through the whole period...

  11. Efficacy of sulfonamides and Baycox(®) against Isospora suis in experimental infections of suckling piglets.

    Science.gov (United States)

    Joachim, Anja; Mundt, Hans-Christian

    2011-12-01

    Sulfonamide treatment of piglets against neonatal coccidiosis has frequently been suggested in the literature. In order to evaluate the efficacy of sulfonamides against experimental Isospora suis infections in suckling piglets (oral infection with 1,500 sporulated oocysts of I. suis per piglet on the fourth day of life), two trials were conducted. In trial I, oral sulfadimidine (group Sulfa-Oral) was applied in doses of 100 mg/kg of body weight (BW) 1 day before infection and 75 mg/kg BW daily for the following 5 days, and sulfamethoxypyrimidine (SMP) was applied parenterally in daily doses of 75 mg/kg BW for the same time period. In trial II, SMP was applied parenterally in doses of 75 mg/kg BW (a) from the day of infection daily for 7 days (SMP-Standard), (b) for 2 days starting on the day of infection (SMP-Early), (c) for 3 days starting 2 days post-infection (d.p.i.; SMP-Middle), (d) for 2 days starting 5 d.p.i. (SMP-Late), and (e) every other day from the day of infection until 6 d.p.i. (SMP-Alternating), as well as (f) orally in doses of 75 mg/kg BW from the day of infection for 7 days (SMP-Oral). The sulfonamide-treated groups were compared to a toltrazuril-treated group (single oral treatment with Baycox® 5% suspension, 20 mg/kg BW 2 d.p.i.) and to a water-treated Control group. Each group consisted of seven to nine piglets. The parameters evaluated were oocyst excretion and fecal consistency/diarrhea from 4 to 15 d.p.i. Sulfa-Oral, SMP-Early, and SMP-Late had no significant effect in reduction of oocyst excretion and diarrhea, whereas treatment for 3-7 days with SMP reduced both parasite shedding and diarrhea significantly. Oral treatment with SMP was comparable to parenteral application. Baycox® in a single application had the most pronounced effect and completely suppressed oocyst excretion and diarrhea during the examination period. It could be shown that repeated application of sulfonamides, provided that the appropriate time period after infection

  12. An immunohistochemical study of Flexibacter psychrophilus infection in experimentally and naturally infected rainbow trout (Oncorhynchus mykiss) fry

    DEFF Research Database (Denmark)

    Evensen, O.; Lorenzen, Ellen

    1996-01-01

    An immunohistochemical method is described for the detection of Flexibacter psychrophilus in formalin-fixed, parafiin-wax-embedded fry of rainbow trout. Rabbit antiserum as well as rainbow trout hyperimmune serum were used in the study. The distribution and tissue localization of the bacterium wa...... are typically found during the chronic stage of the disease....... and experimentally infected fry showed that there was a localization of bacteria in the monocyte-macrophage system, in skin lesions, and in the retina and the choroid gland of the eye. The dermal changes included superficial or deep ulcers extending to the subcutaneous tissue or the musculature accompanied...... by inflammatory cell infiltrates in which polymorphonuclear inflammatory cells were shown to contain the bacterium in the cytoplasm by immunostaining. The eye changes were likewise a common finding in chronic cases with severe inflammatory changes in the retina and with numerous bacteria in inflammatory (mainly...

  13. Corneal Opacity in Domestic Ducks Experimentally Infected With H5N1 Highly Pathogenic Avian Influenza Virus.

    Science.gov (United States)

    Yamamoto, Y; Nakamura, K; Yamada, M; Mase, M

    2016-01-01

    Domestic ducks can be a key factor in the regional spread of H5N1 highly pathogenic avian influenza (HPAI) virus in Asia. The authors performed experimental infections to examine the relationship between corneal opacity and H5N1 HPAI virus infection in domestic ducks (Anas platyrhyncha var domestica). A total of 99 domestic ducks, including 3 control birds, were used in the study. In experiment 1, when domestic ducks were inoculated intranasally with 2 H5N1 HPAI viruses, corneal opacity appeared more frequently than neurologic signs and mortality. Corneal ulceration and exophthalmos were rare findings. Histopathologic examinations of the eyes of domestic ducks in experiment 2 revealed that corneal opacity was due to the loss of corneal endothelial cells and subsequent keratitis with edema. Influenza viral antigen was detected in corneal endothelial cells and some other ocular cells by immunohistochemistry. Results suggest that corneal opacity is a characteristic and frequent finding in domestic ducks infected with the H5N1 HPAI virus. Confirming this ocular change may improve the detection rate of infected domestic ducks in the field. © The Author(s) 2015.

  14. Infecção natural por Cryptosporidium sp. em aves domésticas comercializadas em mercados municipais do Estado do Rio de Janeiro Natural infection by Cryptosporidium sp. in domestic fowls sold at local markets

    Directory of Open Access Journals (Sweden)

    Raquel Saucier Gomes

    2009-10-01

    Full Text Available O objetivo do trabalho foi comparar a dinâmica, a ocorrência, a morfometria de oocistos e os períodos patentes de Cryptosporidium sp. em aves domésticas, patos (Anas platyrhynchos, pintos (Gallus gallus e codornas (Coturnix japonica, naturalmente infectadas, provenientes de dois mercados municipais do Estado do Rio de Janeiro, Rio de Janeiro (RJ. Houve diferenças quanto à ocorrência da infecção entre os dois locais e entre pintos e patos, mas não entre codornas. Para a morfometria, foram observadas diferenças estatísticas nas medidas dos diâmetros maior e menor e para o índice morfométrico calculado (P0,05. Na comparação do período de eliminação, patos tiveram um maior período com maiores quantidades de oocistos eliminados. Codornas e pintos apresentaram dinâmica de eliminação semelhante e não houve diferença quanto à concentração de oocistos. Pintos foram mais susceptíveis à infecção seguidos por patos e codornas. Pode-se concluir que a infecção natural por Cryptoporidium sp. foi frequente nas aves estudadas. Patos, pintos e codornas podem ser disseminadores do protozoário em mercados municipais do Rio de Janeiro, RJ. Assim, podem constituir risco de infecção.The objective of the current study was comparing the dynamic and occurrence of Cryptosporidium sp., as well as the morphometry and elimination period of oocysts in naturally infected ducks (Anas platyrhynchos, chickens (Gallus gallus and Japanese quails (Coturnix japonica from two local markets of Rio de Janeiro, RJ. There were significant differences considering the occurrence of infection between the two markets, and also between chickens and ducks, but not among Japanese quails. Also, significant statistical differences were observed in morphometry, considering the major and minor diameters of oocysts and the calculated morphometric index (P0.05. According to the elimination period, ducks eliminated oocysts for a longer period and in a higher number

  15. Detection of H5N1 high-pathogenicity avian influenza virus in meat and tracheal samples from experimentally infected chickens.

    Science.gov (United States)

    Das, Amaresh; Spackman, Erica; Thomas, Colleen; Swayne, David E; Suarez, David L

    2008-03-01

    The Asian H5N1 highly pathogenic avian influenza (HPAI) virus causes a systemic disease with high mortality of poultry and is potentially zoonotic. In both chickens and ducks, the virus has been demonstrated to replicate in both cardiac and skeletal muscle cells. Experimentally, H5N1 HPAI virus has been transmitted to chickens through the consumption of raw infected meat. In this study, we investigated virus replication in cardiac and skeletal muscle and in the trachea of chickens after experimental intranasal inoculation with the H5N1 HPAI virus. The virus was detected in tissues by real-time reverse transcription-polymerase chain reaction (RRT-PCR) and virus isolation, and in the trachea by RRT-PCR and a commercial avian influenza (AI) viral antigen detection test. A modified RNA extraction protocol was developed for rapid detection of the virus in tissues by RRT-PCR. The H5N1 HPAI virus was sporadically detected in meat and the tracheas of infected birds without any clinical sign of disease as early as 6 hr postinfection (PI), and was detected in all samples tested at 24 hr PI and later. No differences in sensitivity were seen between virus isolation and RRT-PCR in meat samples. The AI viral antigen detection test on tracheal swabs was a useful method for identifying infected chickens when they were sick or dead, but was less sensitive in detecting infected birds when they were preclinical. This study provides data indicating that preslaughter tracheal swab testing can identify birds infected with HPAI among the daily mortality and prevent infected flocks from being sent to processing plants. In addition, the modified RNA extraction and RRT-PCR test on meat samples provide a rapid and sensitive method of identifying HPAI virus in illegal contraband or domestic meat samples.

  16. Experimental Model of Tuberculosis in the Domestic Goat after Endobronchial Infection with Mycobacterium caprae ▿

    Science.gov (United States)

    Pérez de Val, Bernat; López-Soria, Sergio; Nofrarías, Miquel; Martín, Maite; Vordermeier, H. Martin; Villarreal-Ramos, Bernardo; Romera, Nadine; Escobar, Manel; Solanes, David; Cardona, Pere-Joan; Domingo, Mariano

    2011-01-01

    Caprine tuberculosis (TB) has increased in recent years, highlighting the need to address the problem the infection poses in goats. Moreover, goats may represent a cheaper alternative for testing of prototype vaccines in large ruminants and humans. With this aim, a Mycobacterium caprae infection model has been developed in goats. Eleven 6-month-old goats were infected by the endobronchial route with 1.5 × 103 CFU, and two other goats were kept as noninfected controls. The animals were monitored for clinical and immunological parameters throughout the experiment. After 14 weeks, the goats were euthanized, and detailed postmortem analysis of lung lesions was performed by multidetector computed tomography (MDCT) and direct observation. The respiratory lymph nodes were also evaluated and cultured for bacteriological analysis. All infected animals were positive in a single intradermal comparative cervical tuberculin (SICCT) test at 12 weeks postinfection (p.i.). Gamma interferon (IFN-γ) antigen-specific responses were detected from 4 weeks p.i. until the end of the experiment. The humoral response to MPB83 was especially strong at 14 weeks p.i. (13 days after SICCT boost). All infected animals presented severe TB lesions in the lungs and associated lymph nodes. M. caprae was recovered from pulmonary lymph nodes in all inoculated goats. MDCT allowed a precise quantitative measure of TB lesions. Lesions in goats induced by M. caprae appeared to be more severe than those induced in cattle by M. bovis over a similar period of time. The present work proposes a reliable new experimental animal model for a better understanding of caprine tuberculosis and future development of vaccine trials in this and other species. PMID:21880849

  17. Peste des Petits Ruminants Virus Tissue Tropism and Pathogenesis in Sheep and Goats following Experimental Infection

    Science.gov (United States)

    Truong, Thang; Boshra, Hani; Embury-Hyatt, Carissa; Nfon, Charles; Gerdts, Volker; Tikoo, Suresh; Babiuk, Lorne A.; Kara, Pravesh; Chetty, Thireshni; Mather, Arshad; Wallace, David B.; Babiuk, Shawn

    2014-01-01

    Peste des petits ruminants (PPR) is a viral disease which primarily affects small ruminants, causing significant economic losses for the livestock industry in developing countries. It is endemic in Saharan and sub-Saharan Africa, the Middle East and the Indian sub-continent. The primary hosts for peste des petits ruminants virus (PPRV) are goats and sheep; however recent models studying the pathology, disease progression and viremia of PPRV have focused primarily on goat models. This study evaluates the tissue tropism and pathogenesis of PPR following experimental infection of sheep and goats using a quantitative time-course study. Upon infection with a virulent strain of PPRV, both sheep and goats developed clinical signs and lesions typical of PPR, although sheep displayed milder clinical disease compared to goats. Tissue tropism of PPRV was evaluated by real-time RT-PCR and immunohistochemistry. Lymph nodes, lymphoid tissue and digestive tract organs were the predominant sites of virus replication. The results presented in this study provide models for the comparative evaluation of PPRV pathogenesis and tissue tropism in both sheep and goats. These models are suitable for the establishment of experimental parameters necessary for the evaluation of vaccines, as well as further studies into PPRV-host interactions. PMID:24498032

  18. Toxicity and hazard of vanadium to mallard ducks (Anas platyrhynchos) and Canada geese (Branta canadensis)

    Science.gov (United States)

    Rattner, Barnett A.; McKernan, Moira A.; Eisenreich, Karen M.; Link, William A.; Olsen, Glenn H.; Hoffman, David J.; Knowles, K.A.; McGowan, Peter C.

    2006-01-01

    A recent Canada goose (Branta canadensis) die-off at a petroleum refinery fly ash pond in Delaware was attributed to vanadium (V) toxicity. Because of the paucity of V toxicity data for wild birds, a series of studies was undertaken using the forms of V believed to have resulted in this incident. In 7-d single oral dose trials with mallard drakes (Anas platyrhynchos), the estimated median lethal dose (LD50) for vanadium pentoxide was 113 mg/kg body weight, while the LD50 for sodium metavanadate was 75.5 mg/kg. Sodium metavanadate was found to be even more potent (LD50 = 37.2 mg/kg) in male Canada geese. The most distinctive histopathological lesion of both forms of V was lympho-granulocytic enteritis with hemorrhage into the intestinal lumen. Vanadium accumulation in liver and kidney was proportional to the administered dose, and predictive analyses based on these data suggest that V concentrations of 10 μg/g dry weight (dw) in liver and 25 μg/g dw in kidney are associated with mortality (>90% confidence that exposure is >LD50) in mallards acutely exposed to sodium metavanadate. Chronic exposure to increasing dietary concentrations of sodium metavanadate (38.5 to 2651 ppm) over 67 d resulted in V accumulation in liver and kidney (25.2 and 13.6 μg/g dw, respectively), mild intestinal hemorrhage, blood chemistry changes, and evidence of hepatic oxidative stress in mallards, although some of these responses may have been confounded by food avoidance and weight loss. Dietary exposure of mallards to 250 ppm sodium metavanadate for 4 wk resulted in modest accumulation of V in liver and kidney (<5 μg/g dw) and mild intestinal hemorrhage. Based on these data and other observations, it is unlikely that chronic low-level dietary exposure to V poses a direct lethal hazard to wildlife. However, point sources, such as the V-laden fly ash pond encountered by geese at the petroleum refinery in Delaware, may pose a significant hazard to water birds.

  19. Evaluation of the therapeutic effect of potassium permanganate at early stages of an experimental acute infection of Flavobacterium columnare in channel catfish (Ictalurus punctatus)

    Science.gov (United States)

    The efficacy of potassium permanganate (KMnO4) against early stages of an experimental acute infection of Flavobacterium columnare in channel catfish (Ictalurus punctatus) was evaluated. Fish were experimentally challenged, by waterborne exposure for 2 h to F. columnare after cutaneous abrasion, an...

  20. Distribution patterns and predilection muscles of Trichinella zimbabwensis larvae in experimentally infected Nile crocodiles (Crocodylus niloticus Laurenti

    Directory of Open Access Journals (Sweden)

    Louis J. La Grange

    2014-02-01

    Full Text Available No controlled studies have been conducted to determine the predilection muscles of Trichinella zimbabwensis larvae in Nile crocodiles (Crocodylus niloticus or the influence of infection intensity on the distribution of the larvae in crocodiles. The distribution of larvae in muscles of naturally infected Nile crocodiles and experimentally infected caimans (Caiman crocodilus and varans (Varanus exanthematicus have been reported in literature. To determine the distribution patterns of T. zimbabwensis larvae and predilection muscles, 15 crocodiles were randomly divided into three cohorts of five animals each, representing high infection (642 larvae/kg of bodyweight average, medium infection (414 larvae/kg of bodyweight average and low infection (134 larvae/kg of bodyweight average cohorts. In the high infection cohort, high percentages of larvae were observed in the triceps muscles (26% and hind limb muscles (13%. In the medium infection cohort, high percentages of larvae were found in the triceps muscles (50%, sternomastoid (18% and hind limb muscles (13%. In the low infection cohort, larvae were mainly found in the intercostal muscles (36%, longissimus complex (27%, forelimb muscles (20% and hind limb muscles (10%. Predilection muscles in the high and medium infection cohorts were similar to those reported in naturally infected crocodiles despite changes in infection intensity. The high infection cohort had significantly higher numbers of larvae in the sternomastoid, triceps, intercostal, longissimus complex, external tibial flexor, longissimus caudalis and caudal femoral muscles (p < 0.05 compared with the medium infection cohort. In comparison with the low infection cohort, the high infection cohort harboured significantly higher numbers of larvae in all muscles (p < 0.05 except for the tongue. The high infection cohort harboured significantly higher numbers of larvae (p < 0.05 in the sternomastoid, triceps, intercostal, longissimus complex

  1. [Five steps to decreasing nosocomial infections in large immature premature infants: A quasi-experimental study].

    Science.gov (United States)

    García González, Ana; Leante Castellanos, José Luis; Fuentes Gutiérrez, Carmen; Lloreda García, José María; Fernández Fructuoso, José Ramón; Gómez Santos, Elisabet; García González, Verónica

    2017-07-01

    An evaluation is made of the impact of a series of five interventions on the incidence of hospital-related infections in a level iii neonatal unit. Quasi-experimental, pre-post intervention study, which included preterm infants weighing 1,500g at birth or delivered at <32 weeks gestation, admitted in the 12 months before and after the measures were implemented (January 2014). The measures consisted of: optimising hand washing, following a protocol for insertion and handling of central intravenous catheters, encouraging breastfeeding; applying a protocol for rational antibiotic use, and establishing a surveillance system for multi-resistant bacteria. The primary endpoint was to assess the incidence of hospital-acquired infections before and after implementing the interventions. Thirty-three matched patients were included in each period. There was an incidence of 8.7 and 2.7 hospital-related infections/1,000 hospital stay days in the pre- and post-intervention periods, respectively (P<.05). Additionally, patients in the treatment group showed a statistically-significant decrease in days on mechanical ventilation, use of blood products, and vasoactive drugs. The strategy, based on implementing five specific measures in a unit with a high rate of hospital-related infections, proved effective in reducing their incidence. This reduction could contribute to lowering the use of mechanical ventilation, blood products, and vasoactive drugs. Copyright © 2016 Asociación Española de Pediatría. Publicado por Elsevier España, S.L.U. All rights reserved.

  2. Assessment of Domestic Goats as Models for Experimental and Natural Infection with the North American Isolate of Rickettsia slovaca.

    Science.gov (United States)

    Lukovsky-Akhsanov, Nicole; Keating, M Kelly; Spivey, Pamela; Lathrop, George W; Powell, Nathaniel; Levin, Michael L

    2016-01-01

    Rickettsia slovaca is a tick-borne human pathogen that is associated with scalp eschars and neck lymphadenopathy known as tick-borne lymphadenopathy (TIBOLA) or Dermacentor-borne necrosis erythema and lymphadenopathy (DEBONEL). Originally, R. slovaca was described in Eastern Europe, but since recognition of its pathogenicity, human cases have been reported throughout Europe. European vertebrate reservoirs of R. slovaca remain unknown, but feral swine and domestic goats have been found infected or seropositive for this pathogen. Recently, a rickettsial pathogen identical to R. slovaca was identified in, and isolated from, the American dog tick, Dermacentor variabilis. In previous experimental studies, this organism was found infectious to guinea pigs and transovarially transmissible in ticks. In this study, domestic goats (Capra hircus) were experimentally inoculated with the North American isolate of this R. slovaca-like agent to assess their reservoir competence-the ability to acquire the pathogens and maintain transmission between infected and uninfected ticks. Goats were susceptible to infection as demonstrated by detection of the pathogen in skin biopsies and multiple internal tissues, but the only clinical sign of illness was transient fever noted in three out of four goats, and reactive lymphoid hyperplasia. On average, less than 5% of uninfected ticks acquired the pathogen while feeding upon infected goats. Although domestic goats are susceptible to the newly described North American isolate of R. slovaca, they are likely to play a minor role in the natural transmission cycle of this pathogen. Our results suggest that goats do not propagate the North American isolate of R. slovaca in peridomestic environments and clinical diagnosis of infection could be difficult due to the brevity and mildness of clinical signs. Further research is needed to elucidate the natural transmission cycle of R. slovaca both in Europe and North America, as well as to identify a

  3. Experimental infection of macaques with a wild water bird-derived highly pathogenic avian influenza virus (H5N1.

    Directory of Open Access Journals (Sweden)

    Tomoko Fujiyuki

    Full Text Available Highly pathogenic avian influenza virus (HPAIV continues to threaten human health. Non-human primate infection models of human influenza are desired. To establish an animal infection model with more natural transmission and to determine the pathogenicity of HPAIV isolated from a wild water bird in primates, we administered a Japanese isolate of HPAIV (A/whooper swan/Hokkaido/1/2008, H5N1 clade 2.3.2.1 to rhesus and cynomolgus monkeys, in droplet form, via the intratracheal route. Infection of the lower and upper respiratory tracts and viral shedding were observed in both macaques. Inoculation of rhesus monkeys with higher doses of the isolate resulted in stronger clinical symptoms of influenza. Our results demonstrate that HPAIV isolated from a water bird in Japan is pathogenic in monkeys by experimental inoculation, and provide a new method for HPAIV infection of non-human primate hosts, a good animal model for investigation of HPAIV pathogenicity.

  4. Immunodiagnosis of systemic aspergillosis. I. Antigenemia detected by radioimmunoassay in experimental infection. [/sup 125/I tracer technique

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    Weiner, M.H.; Coats-Stephen, M.

    1979-01-01

    Because systemic aspergillosis is difficult to diagnose ante mortem, a study to improve immunodiagnosis was undertaken in a rabbit model of disseminated infection. We found that the predominant humoral response of infected animals was directed against four Aspergillus antigens identified by crossed immunoelectrophoresis. One of these antigens, a cell-wall carbohydrate, was purified by gel-filtration chromatography and was used to develop a radiommunoassay. The sensitivity of this assay was increased by testing for serum-bound antigen as well as for free antigen. When the sensitivity of the RIA was evaluated in the animal model, antigenemia was detected in 78% of 51 rabbits with disseminated infection and ante mortem in 86% of 42 rabbits with lethal infection. By contrast, with immunoprecipitin analysis only eight of 51 rabbits were positive for antigen, and six of 51 rabbits were positive for Aspergillus antibody. The specificity of the RIA was also tested. Negative controls for antigen included sera from 76 normal rabbits and sera from 25 rabbits with systemic candidiasis. The Candida control group is pertinent because 48% of these rabbits had specific Candida antigenemia detected by a mannan RIA. This study demonstrates that Aspergillus antigenemia occurs during the course of experimental disseminated aspergillosis and illustrates the potential of an Aspergillus antigen RIA for sensitive, specific immunodiagnosis of human infections.

  5. A novel approach to parasite population genetics: experimental infection reveals geographic differentiation, recombination and host-mediated population structure in Pasteuria ramosa, a bacterial parasite of Daphnia.

    Science.gov (United States)

    Andras, J P; Ebert, D

    2013-02-01

    The population structure of parasites is central to the ecology and evolution of host-parasite systems. Here, we investigate the population genetics of Pasteuria ramosa, a bacterial parasite of Daphnia. We used natural P. ramosa spore banks from the sediments of two geographically well-separated ponds to experimentally infect a panel of Daphnia magna host clones whose resistance phenotypes were previously known. In this way, we were able to assess the population structure of P. ramosa based on geography, host resistance phenotype and host genotype. Overall, genetic diversity of P. ramosa was high, and nearly all infected D. magna hosted more than one parasite haplotype. On the basis of the observation of recombinant haplotypes and relatively low levels of linkage disequilibrium, we conclude that P. ramosa engages in substantial recombination. Isolates were strongly differentiated by pond, indicating that gene flow is spatially restricted. Pasteuria ramosa isolates within one pond were segregated completely based on the resistance phenotype of the host-a result that, to our knowledge, has not been previously reported for a nonhuman parasite. To assess the comparability of experimental infections with natural P. ramosa isolates, we examined the population structure of naturally infected D. magna native to one of the two source ponds. We found that experimental and natural infections of the same host resistance phenotype from the same source pond were indistinguishable, indicating that experimental infections provide a means to representatively sample the diversity of P. ramosa while reducing the sampling bias often associated with studies of parasite epidemics. These results expand our knowledge of this model parasite, provide important context for the large existing body of research on this system and will guide the design of future studies of this host-parasite system. © 2012 Blackwell Publishing Ltd.

  6. Desenvolvimento de um modelo experimental de falha óssea infectada na ulna de coelhos Development of an experimental model of infected bone void in the ulna of rabbits

    Directory of Open Access Journals (Sweden)

    Matheus Lemos Azi

    2012-01-01

    Full Text Available OBJETIVO: Desenvolver um modelo experimental que permita estudar a regeneração de grandes falhas ósseas em condições de infecção. MÉTODO: Falhas ósseas segmentares de 15mm foram criadas cirurgicamente na ulna de 12 coelhos e inoculadas com 5x10(8 unidades formadoras de colônia (UFC de S. aureus. O desbridamento da infecção foi realizado duas semanas após, seguida da aplicação sistêmica de gentamicina por quatro semanas. Os animais foram acompanhados por um período de 12 semanas para avaliação do controle da infecção e da regeneração óssea. RESULTADOS: A regeneração espontânea foi inferior a 25% do defeito na avaliação radiográfica e histológica. CONCLUSÃO: A Falha óssea infectada de 15mm na ulna de coelhos é incapaz de alcançar a regeneração completa sem tratamentos adicionais. Nível de Evidência V, Estudo experimental.OBJECTIVE: Develop a model that allowed the study of bone regeneration in infection conditions. METHOD: A 15 mm defect was surgically created in the rabbit ulna and inoculated with 5x10(8 colony-forming units (CFU of S. aureus. Surgical debridement was performed two weeks after and systemic gentamicin was administered for four weeks. Animals were followed up to 12 weeks to evaluate infection control and bone regeneration. RESULT: Bone regeneration was inferior to 25% of the defect in radiological and histological analysis. CONCLUSION: Infected bone defect of 15 mm in the rabbit ulna was unable to achieve full regeneration without further treatment. Level of Evidence V, Experimental Study.

  7. EXPERIMENTAL INFECTION BY Trypanosoma vivax IN GOATS INFECÇÃO EXPERIMENTAL EM CAPRINOS COM Trypanosoma vivax

    Directory of Open Access Journals (Sweden)

    Francisco David Nascimento Sousa

    2008-10-01

    Full Text Available

    Four goats were infected intravenously with 1.0 mL of cattle blood containing about 1.25 x 105 Trypanosoma vivax derived from spontaneous outbreak in cattle at Catolé do Rocha city, Paraíba, Brazil. Other four goats were used as controls. Parasitemia and body temperature were determined daily for 40 days. Animals were weighted each 7 days, and blood samples for blood cells counts were collected each 5 days. It was obtained a sample of liquor from each animal before death; cerebrospinal fluid samples were submitted to biochemical and cytological evaluations, density determination and parasite detection. A positive correlation was found between body temperature and parasitemia in infected animals. These animals presented anemia, leukopenia, hypoglycemia, decreased serum levels of total proteins and cholesterol, and nervous symptoms. Examination of cerebrospinal fluid resulted in decrease of glucose levels and increase in lactate dehydrogenase, cell counts and presence of the parasite. At necropsy it was found pale carcass, generalized infartation of lymphonodes, pulmonary edema, and liquid accumulation of pericardium. Histological changes were characterized by interstitial pneumonia, miocarditis, cardiac fibrosis, meningitis, and encephalitis. All observed changes confirm patogenicity of T. vivax.

    KEY WORDS: Experimental infection, trypanosomiasis, patogenicity.

    Quatro caprinos foram infectados experimentalmente por via intravenosa com 1,0 ml de sangue contendo aproximadamente 1,25 x 105 tripanossomas/ml, utilizando-se um isolado de Trypanosoma vivax de bovinos infectados naturalmente no município de Catolé do Rocha, Paraíba. A parasitemia e a temperatura foram determinadas diariamente durante quarenta dias. A cada cinco dias realizaram-se coletas de sangue para hemograma e análise bioquímica sérica. Antes do

  8. Highly (H5N1 and low (H7N2 pathogenic avian influenza virus infection in falcons via nasochoanal route and ingestion of experimentally infected prey.

    Directory of Open Access Journals (Sweden)

    Kateri Bertran

    Full Text Available An experimental infection with highly pathogenic avian influenza (HPAI and low pathogenic avian influenza (LPAI viruses was carried out on falcons in order to examine the effects of these viruses in terms of pathogenesis, viral distribution in tissues and viral shedding. The distribution pattern of influenza virus receptors was also assessed. Captive-reared gyr-saker (Falco rusticolus x Falco cherrug hybrid falcons were challenged with a HPAI H5N1 virus (A/Great crested grebe/Basque Country/06.03249/2006 or a LPAI H7N2 virus (A/Anas plathyrhynchos/Spain/1877/2009, both via the nasochoanal route and by ingestion of previously infected specific pathogen free chicks. Infected falcons exhibited similar infection dynamics despite the different routes of exposure, demonstrating the effectiveness of in vivo feeding route. H5N1 infected falcons died, or were euthanized, between 5-7 days post-infection (dpi after showing acute severe neurological signs. Presence of viral antigen in several tissues was confirmed by immunohistochemistry and real time RT-PCR (RRT-PCR, which were generally associated with significant microscopical lesions, mostly in the brain. Neither clinical signs, nor histopathological findings were observed in any of the H7N2 LPAI infected falcons, although all of them had seroconverted by 11 dpi. Avian receptors were strongly present in the upper respiratory tract of the falcons, in accordance with the consistent oral viral shedding detected by RRT-PCR in both H5N1 HPAI and H7N2 LPAI infected falcons. The present study demonstrates that gyr-saker hybrid falcons are highly susceptible to H5N1 HPAI virus infection, as previously observed, and that they may play a major role in the spreading of both HPAI and LPAI viruses. For the first time in raptors, natural infection by feeding on infected prey was successfully reproduced. The use of avian prey species in falconry husbandry and wildlife rehabilitation facilities could put valuable birds

  9. Highly (H5N1) and low (H7N2) pathogenic avian influenza virus infection in falcons via nasochoanal route and ingestion of experimentally infected prey.

    Science.gov (United States)

    Bertran, Kateri; Busquets, Núria; Abad, Francesc Xavier; García de la Fuente, Jorge; Solanes, David; Cordón, Iván; Costa, Taiana; Dolz, Roser; Majó, Natàlia

    2012-01-01

    An experimental infection with highly pathogenic avian influenza (HPAI) and low pathogenic avian influenza (LPAI) viruses was carried out on falcons in order to examine the effects of these viruses in terms of pathogenesis, viral distribution in tissues and viral shedding. The distribution pattern of influenza virus receptors was also assessed. Captive-reared gyr-saker (Falco rusticolus x Falco cherrug) hybrid falcons were challenged with a HPAI H5N1 virus (A/Great crested grebe/Basque Country/06.03249/2006) or a LPAI H7N2 virus (A/Anas plathyrhynchos/Spain/1877/2009), both via the nasochoanal route and by ingestion of previously infected specific pathogen free chicks. Infected falcons exhibited similar infection dynamics despite the different routes of exposure, demonstrating the effectiveness of in vivo feeding route. H5N1 infected falcons died, or were euthanized, between 5-7 days post-infection (dpi) after showing acute severe neurological signs. Presence of viral antigen in several tissues was confirmed by immunohistochemistry and real time RT-PCR (RRT-PCR), which were generally associated with significant microscopical lesions, mostly in the brain. Neither clinical signs, nor histopathological findings were observed in any of the H7N2 LPAI infected falcons, although all of them had seroconverted by 11 dpi. Avian receptors were strongly present in the upper respiratory tract of the falcons, in accordance with the consistent oral viral shedding detected by RRT-PCR in both H5N1 HPAI and H7N2 LPAI infected falcons. The present study demonstrates that gyr-saker hybrid falcons are highly susceptible to H5N1 HPAI virus infection, as previously observed, and that they may play a major role in the spreading of both HPAI and LPAI viruses. For the first time in raptors, natural infection by feeding on infected prey was successfully reproduced. The use of avian prey species in falconry husbandry and wildlife rehabilitation facilities could put valuable birds of prey and

  10. Comparative haematological changes in experimentally infected ...

    African Journals Online (AJOL)

    STORAGESEVER

    2008-07-04

    Jul 4, 2008 ... However, disease such as animal trypanosomiasis possess a great risk to their ... The severity of the infection is influenced by a number of factors .... agrees with a similar work in which a significant fall in packed cell volume ... Heat production, body temperature and body posture in West. African dwarf goats ...

  11. [Experimental study of the effects of impulse-electric discharge on chemotaxis and cytoadhesion of urinary infection pathogens].

    Science.gov (United States)

    Kuderinov, S K; Azizov, I S; Turgunov, E M; Shambilova, N A

    2006-01-01

    The aim of the experimental study was to evaluate effects of impulse-electric discharge in liquid on chemotaxis and cytoadhesion of urinary infection pathogens. Chemotaxis was determined in respect to the lung, liver, spleen, kidney, ureter, urinary bladder, urethra of white mice by S. Likholetov's modified method. Cytoadhesion was assessed by V. Brilis. The experiments show that the impulse-electric discharge holds promise for urological practice.

  12. Cholinesterase as inflammatory markers in a experimental infection by Trypanosoma evansi in rabbits

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    Márcio M. Costa

    2012-12-01

    Full Text Available The aim of this study is to evaluate the role of cholinesterases as an inflammatory marker in acute and chronic infection by Trypanosoma evansi in rabbits experimentally infected. Twelve adult female New Zealand rabbits were used and divided into two groups with 6 animals each: control group (rabbits 1-6 and infected group (rabbits 7-12. Infected group received intraperitoneally 0.5 mL of blood from a rat containing 108 parasites per animal. Blood samples used for cholinesterases evaluation were collected on days 0, 2, 7, 12, 27, 42, 57, 87, 102 and 118 days post-inoculation (PI. Increased activity (P0.05 was observed in the encephalic structures. The increased activities of AChE and BChE probably have a pro-inflammatory purpose, attempting to reduce the concentration of acetylcholine, a neurotransmitter which has an anti-inflammatory property. Therefore, cholinesterase may be inflammatory markers in infection with T. evansi in rabbits.O objetivo do presente estudo é avaliar o papel das colinesterases como marcadores inflamatórios nas fases aguda e crônica da infecção por T. evansi em coelhos infectados experimentalmente. Foram utilizados 12 coelhos adultos, fêmeas, da raça Nova Zelândia, divididos em dois grupos: um grupo controle, com seis animais (coelhos 1-6, e um grupo infectado, com seis animais (coelhos 7-12. Os animais pertencentes ao grupo infectados receberam, pela via intraperitoneal, 0,5 mL de sangue de rato contendo 108 tripanossomas por animal. Amostras do sangue utilizado para avaliação das colinesterases foram coletadas nos dias 0, 2, 7, 12, 27, 42, 57, 87, 102 e 118 pós-inoculação (PI. Aumento (P0,05 foi observada nas estruturas encefálicas. O aumento de atividade da AChE e BChE provavelmente tenha finalidade pró-inflamatória, a fim de reduzir as concentrações de acetilcolina, neurotransmissor que apresenta propriedade anti-inflamatória. Portanto, as colinesterases podem ser marcadores inflamatórios na infec

  13. Histopathological changes in the kidneys of vertebrate hosts infected naturally and experimentally withParatanaisia bragai (Trematoda, Digenea

    Directory of Open Access Journals (Sweden)

    Vanessa Barreto Xavier

    Full Text Available Paratanaisia bragai is a trematode parasite that reaches sexual maturity in the kidney collecting ducts of domesticated and wild fowl and whose intermediate hosts are the snails Subulina octona and Leptinaria unilamellata. There are some discrepancies in descriptions of the pathology of this parasite in bird kidneys. Therefore, the purpose of this study was to analyze the kidneys of rock pigeons (Columba livia naturally infected and of chickens (Gallus gallus experimentally infected with Paratanaisia bragai, by means of macroscopic observation and by light and scanning electron microscopy. Both bird species showed significantly dilated collecting ducts. In addition, lymphocyte infiltration was observed in the kidneys of C. livia and metaplasia in the epithelial lining of the kidney collecting ducts of G. gallus.

  14. Histomorphological study of the parathyroid gland in female Kuttanad ducks (Anas platyrhynchos domesticus

    Directory of Open Access Journals (Sweden)

    Firdous Ahmad Dar

    2013-11-01

    Full Text Available Aim: The present work was targeted to form the baseline data of normal morphological and histological picture of parathyroid gland in female Kuttanad ducks.Materials and Methods: A Histomorphological study of the parathyroid gland was carried out in twelve adult female Kuttanad ducks (Anas platyrhynchos domesticus of 20 weeks of age. Birds reared semintensively were procured from Kerala Veterinary and Animal Sciences University Poultry and Duck Farm and sacrificed humanely. Glands were collected and gross parameters were recorded. The glands were fixed in 10 percent neutral buffered formalin. The small sized glands were processed as such by routine histological methods, paraffin blocks were prepared and sectioned to a thickness of 5µ. The tissues were stained by Haematoxylin and Eosin (H&E for routine histological studies and Gomori's rapid one step trichrome method for connective tissue fibres. Micrometric parameters were recorded using ocular micrometer. Results: Parathyroid glands in Kuttanad ducks lay just caudal to the division of the innominate artery into the subclavian and common carotid arteries. Parathyroids were oval to spherical in shape, yellow in colour and smaller than thyroid gland of the representative sides. The arterial blood supply was from common carotid artery and blood from gland was drained directly into jugular vein. Although it lied close to the thyroid, thymus and ultimobranchial gland, parathyroid tissue did not merge to any of the above mentioned three glands. Parenchyma was composed irregular anatomizing cords of cells supplied by connective tissue stroma penetrated by blood capillaries. Parenchyma was predominantly made of lightly stained cell, the chief cell. The nuclei were round and contain one or two nucleoli. Oxyphil cells present in parathyroid glands of other mammals were not seen in the present study. Conclusion: Histomorphological features or characteristics of Parathyroid gland in Kuttanad duck were

  15. Effects of Non-Susceptible Hosts on the Infection with Trypanosoma cruzi of the Vector Triatoma infestans: an Experimental Model

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    Vázquez Diego P

    1999-01-01

    Full Text Available We tested experimentally the effects of the presence of non-susceptible hosts on the infection with Trypanosoma cruzi of the vector Triatoma infestans. The experiment consisted in two treatments: with chickens, including two chickens (non-susceptible hosts and two infected guinea pigs (susceptible hosts, and without chickens, including only two infected guinea pigs. The hosts were held unrestrained in individual metal cages inside a closed tulle chamber. A total of 200 uninfected T. infestans third instar nymphs were liberated in each replica, collected on day 14, and examined for infection and blood meal sources on day 32-36. The additional presence of chickens relative to infected guinea pigs: (a significantly modified the spatial distribution of bugs; (b increased significantly the likelihoods of having a detectable blood meal on any host and molting to the next instar; (c did not affect the bugs' probability of death by predation; and (d decreased significantly the overall percentage of T. infestans infected with T. cruzi. The bugs collected from inside or close to the guinea pigs' cages showed a higher infection rate (71-88% than those collected from the chickens' cages (22-32%. Mixed blood meals on chickens and guinea pigs were detected in 12-21% of bugs. Although the presence of chickens would decrease the overall percentage of infected bugs in short term experiments, the high rate of host change of T. infestans would make this difference fade out if longer exposure times had been provided.

  16. Evaluation of tiamulin and lincomycin for the treatment of broiler breeders experimentally infected with the intestinal spirochaete Brachyspira pilosicoli.

    Science.gov (United States)

    Stephens, C P; Hampson, D J

    2002-06-01

    Brachyspira pilosicoli strain CPSp1 isolated from a chicken in a broiler breeder flock in Queensland was used to experimentally infect 30 individually caged 22-week-old Cobb 500 broiler breeder hens. Another 10 birds were sham-inoculated with sterile broth. All birds failed to become colonized. At 29 weeks of age, all birds were transferred to a diet containing 50 parts/10(6) zinc bacitracin (ZnB) and were re-challenged with the same B. pilosicoli strain at 32 weeks of age, weekly for 5 weeks. The majority of the inoculated birds then became colonized, confirming previous findings that ZnB can increase susceptibility to colonization with B. pilosicoli. The control group remained uninfected. Infected groups tended to have an increased faecal water content and faecal staining of eggshells. Ten birds were then treated by crop tube with 25 mg/kg body weight tiamulin for 5 days, and 10 birds with 20 mg/kg body weight lincomycin for 5 days. Both treatments removed the infection, while untreated birds remained infected. The results support previous observations that ZnB at 50 parts/10(6) in the diet increases the susceptibility of birds to B. pilosicoli infection, and demonstrated the usefulness of both tiamulin and lincomycin for treatment of infection with B. pilosicoli in adult birds.

  17. Aeromonas caviae alters the cytosolic and mitochondrial creatine kinase activities in experimentally infected silver catfish: Impairment on renal bioenergetics.

    Science.gov (United States)

    Baldissera, Matheus D; Souza, Carine F; Júnior, Guerino B; Verdi, Camila Marina; Moreira, Karen L S; da Rocha, Maria Izabel U M; da Veiga, Marcelo L; Santos, Roberto C V; Vizzotto, Bruno S; Baldisserotto, Bernardo

    2017-09-01

    Cytosolic and mitochondrial creatine kinases (CK), through the creatine kinase-phosphocreatine (CK/PCr) system, provide a temporal and spatial energy buffer to maintain cellular energy homeostasis. However, the effects of bacterial infections on the kidney remain poorly understood and are limited only to histopathological analyses. Thus, the aim of this study was to investigate the involvement of cytosolic and mitochondrial CK activities in renal energetic homeostasis in silver catfish experimentally infected with Aeromonas caviae. Cytosolic CK activity decreased in infected animals, while mitochondrial CK activity increased compared to uninfected animals. Moreover, the activity of the sodium-potassium pump (Na + , K + -ATPase) decreased in infected animals compared to uninfected animals. Based on this evidence, it can be concluded that the inhibition of cytosolic CK activity by A. caviae causes an impairment on renal energy homeostasis through the depletion of adenosine triphosphate (ATP) levels. This contributes to the inhibition of Na + , K + -ATPase activity, although the mitochondrial CK activity acted in an attempt to restore the cytosolic ATP levels through a feedback mechanism. In summary, A. caviae infection causes a severe energetic imbalance in infected silver catfish, which may contribute to disease pathogenesis. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Infecções experimentaes na Leishmaniose visceral americana Experimental infections in american visceral leishmaniasis

    Directory of Open Access Journals (Sweden)

    Aristides Marques da Cunha

    1938-01-01

    sôro-agglutinação, conforme mostramos em trabalho anterior, não permite a separação das especies do genero Leishmania, pois todas ellas, quando recentemente isoladas, possuem identica constituição antigenica, que se modifica depois, pela conservação longo tempo em cultura. É esse facto, que deu logar ás conclusões contradictorias a que chegaram os autores que se ocuparam do assumpto bem como os primeiros resultados que obtivemos. Deante de todos esses factos, nos julgamos autorizados a concluir como já fizemos anteriormente, que o agente da Leishmaniose visceral americana é identico á Leishmania infantum. Ao terminar, queremos deixar consignados nossos agradecimentos ao Dr. E. chagas, por ter posto a nossa disposição as culturas de Leishmania por elle isoladas, tornando possivel deste modo, a execução do presente trabalho.With cultures isolated from cases of american visceral leishmaniasis we succeeded in obtaining experimental infections in hamsters (Cricetus cricetus, rhesus monkeys (Macaca mullata and dogs. Hamsters were infected with strains obtained from man and dogs, the intraperitoneal way having been always employed. When cultures recently isolated are used, infection is obtained practically in 100% of the animals inoculated. The first negative results obtained by us may be explained by the use of cultures isolated some time before (about 7 months 0 and which had lost already their virulence. In some cases external lesions are observed represented by alterations of the skin and swelling of the paws. The skin lesions are observed on the ventral surface and consist in depilation, erythema and exudation. The skin thus affected shows to be extremely friable, rupturing at the movements of the animal when hold. On post-mortem examination, besides the lesions pointed out, the animals present enlargement of the spleen. The parasites are very numerous in the spleen, liver, bone marrow, etc. The changed skin shows considerable hypertrophy of the

  19. Humoral immune response of horses experimentally infected with Trypanosoma evansi/ Resposta imune humoral de eqüinos infectados experimentalmente com Trypanosoma evansi

    Directory of Open Access Journals (Sweden)

    Lúcia Padilha Cury Thomaz de Aquino

    2001-05-01

    Full Text Available Six adult horses were experimentally infected with Trypanosoma evansi (106 parasites. Three other adult horses served as negative control. Serum samples of the experimentally infected horses with T. evansi and non-infected controls horses were obtained before inoculation, and daily thereafter until 14 days post infection (DPI. After that time the serum samples were obtained weekly. Sera of the infected and non-infected control horses was tested by indirect fluorescent antibody test (IFAT and enzyme-linked immunosorbent assay (ELISA for the detection of antibodies against T. evansi. Both ELISA and IFAT detected trypanosomal antibodies shortly after infection and showed progressive increases in antibodies levels during early stages of infection. The responses started on the eighth and eleventh DPI. Maximum IFAT and ELISA values were reached after four weeks of infection and were maintained at this level until the end of the period of study.Seis eqüinos foram inoculados com 106 tripomastigota sangüícolas de Trypanosoma evansi. Três outros animais foram mantidos como testemunhas. Amostras de soro sangüíneo foram obtidas de todos os animais, antes da inoculação, e diariamente até o 14º dia pós inoculação (DPI; após este período uma vez por semana. Pesquisa de anticorpos anti- T. evansi, foram realizadas através da reação de imunofluorescência indireta (RIFI e do ensaio de imunoabsorção enzimática (ELISA. A resposta imune humoral, detectada através da RIFI e do ELISA, iniciou-se, em média, a partir do oitavo DPI, alcançando títulos máximos após quatro semanas de evolução, e os titulos de anticorpos anti- T. evansi mantiveram-se elevadas até o término das observações.

  20. Ketoconazole modulates the infectivity of Ichthyophonus sp. (Mesomycetozoa) in vivo in experimentally injected European sea bass

    OpenAIRE

    Hontoria, Francisco; González, Mª Ángeles; Sitjà-Bobadilla, Ariadna; Palenzuela, Oswaldo

    2013-01-01

    In vitro studies have confirmed the inhibitory effect of the azol-derivative ketoconazole (KZ) on the growth of Ichthyophonus, an important pathogen causing epizootics in wild and cultured fish. We evaluated the effect of KZ in vivo in European sea bass Dicentrarchus labrax experimentally infected with the same Ichthyophonus isolate. Liposomes were used to vehiculate different doses of KZ to increase the effect on Ichthyophonus and lower the toxicity of the drug, and KZ toxicity was assessed ...

  1. Brazilian avian metapneumovirus subtypes A and B: experimental infection of broilers and evaluation of vaccine efficacy

    OpenAIRE

    Márcia B. dos Santos; Matheus C. Martini; Helena L. Ferreira; Luciana H.A. da Silva; Paulo A. Fellipe; Fernando R. Spilki; Clarice W. Arns

    2012-01-01

    Santos M.B., Martini M.C., Ferreira H.L., Silva L.H.A., Fellipe P.A., Spilki F.R. & Arns C.W. 2012. Brazilian avian metapneumovirus subtypes A and B: experimental infection of broilers and evaluation of vaccine efficacy. Pesquisa Veterinaria Brasileira 32(12):1257-1262. Laboratorio de Virologia, Instituto de Biologia, Universidade Estadual de Campinas, Rua Monteiro Lobato s/n, Cx. Postal 6109, Campinas, SP 13083-970, Brazil. E-mail: Avian metapneumovirus (aMPV) is a respirator...

  2. Immunologic and hematologic responses in ponies with experimentally induced Strongylus vulgaris infection.

    Science.gov (United States)

    Bailey, M; Martin, S C; Lloyd, S

    1989-08-01

    Immunologic and hematologic responses were examined in 4 ponies with experimentally induced Strongylus vulgaris infection and in 5 helminth-free ponies. Two ponies were inoculated with 200 larvae and 2 were inoculated with 700 larvae of S vulgaris and then were reinoculated with the same numbers of larvae 34 weeks later. Initial response of the ponies inoculated with S vulgaris was S vulgaris antigen-induced lymphocyte response that developed 1.5 to 3 weeks after inoculation and did not persist. Development of antigen-reactive lymphocytes was followed sequentially by a biphasic complement-fixing antibody response, then biphasic eosinophilia. Antibody titer to S vulgaris antigen was higher in ponies inoculated with 700 larvae, compared with that in ponies given 200 larvae of S vulgaris. Also, the second peak in antibody titer and in absolute number of eosinophils was observed earlier in ponies inoculated with 700 larvae, compared with ponies inoculated with 200 S vulgaris larvae, and subsided before or from about 24 weeks after inoculation. The prepatent period for S vulgaris infection was 24 to 25 weeks. After reinoculation with S vulgaris, a degree of increased lymphocyte responsiveness was apparent but, by 17 weeks after reinoculation, only the primary peak in the absolute number of eosinophils indicated an anamnestic response. Essentially, antibody was not detectable after reinoculation.

  3. No evidence of horizontal infection in horses kept in close contact with dogs experimentally infected with canine influenza A virus (H3N8

    Directory of Open Access Journals (Sweden)

    Yamanaka Takashi

    2012-04-01

    Full Text Available Abstract Background Since equine influenza A virus (H3N8 was transmitted to dogs in the United States in 2004, the causative virus, which is called canine influenza A virus (CIV, has become widespread in dogs. To date, it has remained unclear whether or not CIV-infected dogs could transmit CIV to horses. To address this, we tested whether or not close contact between horses and dogs experimentally infected with CIV would result in its interspecies transmission. Methods Three pairs of animals consisting of a dog inoculated with CIV (108.3 egg infectious dose50/dog and a healthy horse were kept together in individual stalls for 15 consecutive days. During the study, all the dogs and horses were clinically observed. Virus titres in nasal swab extracts and serological responses were also evaluated. In addition, all the animals were subjected to a gross pathological examination after euthanasia. Results All three dogs inoculated with CIV exhibited clinical signs including, pyrexia, cough, nasal discharge, virus shedding and seroconversion. Gross pathology revealed lung consolidations in all the dogs, and Streptococcus equi subsp. zooepidemicus was isolated from the lesions. Meanwhile, none of the paired horses showed any clinical signs, virus shedding or seroconversion. Moreover, gross pathology revealed no lesions in the respiratory tracts including the lungs of the horses. Conclusions These findings may indicate that a single dog infected with CIV is not sufficient to constitute a source of CIV infection in horses.

  4. The nutritional status affects the complete blood count of goats experimentally infected with Haemonchus contortus.

    Science.gov (United States)

    Cériac, S; Jayles, C; Arquet, R; Feuillet, D; Félicité, Y; Archimède, H; Bambou, J-C

    2017-11-09

    Gastrointestinal nematode (GIN) remains the most important pathogenic constraint of small ruminant production worldwide. The improvement of the host immune response against GIN though breeding for improved animal resistance, vaccination and nutritional supplementation appear as very promising methods. The objective of this study was to investigate the effect of four nutritional status differing in protein and energy levels (Hay: 5.1 MJ/Kg of dry matter (DM) and 7.6% of crude protein (CP), Ban: 8.3 MJ/Kg of DM and 7.5% of CP, Soy: 7.6 MJ/Kg of DM and 17.3% of CP, BS: 12.7 MJ/Kg of DM and 7.4% of CP) on the haematological disturbances due to Haemonchus contortus infection in Creole kid goats. No significant effect of the nutritional status was observed for faecal egg count (FEC) but the experimental infection induced haematological disturbances whose intensity and lengthening were dependent on the nutritional status. A transient marked regenerative macrocytic hypochromic anaemia as revealed by a decrease of packed cell volume (PCV), red blood cells (RBC) and hemoglobin and an increase of reticulocytes was observed in all infected groups except Hay. In this latter, the anaemia settled until the end of the experiment. Furthermore, H. contortus induced a thrombocytopenia significantly more pronounced in the group under the lowest nutritional status in term of protein (Hay and Ban). A principal component analysis revealed that the variables that discriminated the nutritional status were the average daily gain (ADG) and the PCV, considered as measures of the level of resilience to H. contortus infection. Moreover, the variables that discriminated infected and non-infected animals were mostly related to the biology of RBC (i.e. size and hemoglobin content) and they were correlated with FEC. The severity and the lengthening of the regenerative anaemia and the thrombocytopenia induced by H. contortus have been affected by the nutritional status. The protein enriched

  5. Studies on the Leucocytic Response to Experimental Infection with ...

    African Journals Online (AJOL)

    Also, neutrophil numbers declined significantly (P < 0.05) in red fronted gazelles infected either singly with Trypanosoma brucei or concurrently with both parasites while those infected singly with Haemonchus contortus experienced a significant (P <0.05) rise in neutrophil counts which became evident from day 30 post ...

  6. Experimental in vitro and in vivo systems for studying the innate immune response during dengue virus infections.

    Science.gov (United States)

    Kitab, Bouchra; Kohara, Michinori; Tsukiyama-Kohara, Kyoko

    2018-03-08

    Dengue is the most prevalent arboviral disease in humans and leads to significant morbidity and socioeconomic burden in tropical and subtropical areas. Dengue is caused by infection with any of the four closely related serotypes of dengue virus (DENV1-4) and usually manifests as a mild febrile illness, but may develop into fatal dengue hemorrhagic fever and shock syndrome. There are no specific antiviral therapies against dengue because understanding of DENV biology is limited. A tetravalent chimeric dengue vaccine, Dengvaxia, has finally been licensed for use, but its efficacy was significantly lower against DENV-2 infections and in dengue-naïve individuals. The identification of mechanisms underlying the interactions between DENV and immune responses will help to determine efficient therapeutic and preventive options. It has been well established how the innate immune system responds to DENV infection and how DENV overcomes innate antiviral defenses, however further progress in this field remains hampered by the absence of appropriate experimental dengue models. Herein, we review the available in vitro and in vivo approaches to study the innate immune responses to DENV.

  7. E-ADA activity in erythrocytes of lambs experimentally infected with Haemonchus contortus and its possible functional correlations with anemia.

    Science.gov (United States)

    Da Silva, Aleksandro S; Schafer, Andressa S; Aires, Adelina R; Tonin, Alexandre A; Pimentel, Victor C; Oliveira, Camila B; Zanini, Daniela; Schetinger, Maria R C; Lopes, Sonia T A; Leal, Marta L R

    2013-12-01

    The aim of this study was to evaluate the ecto-adenosine deaminase (E-ADA) activity in erythrocytes of lambs experimentally infected with Haemonchus contortus, correlating it with the degrees of anemia of the experimental animals. A total of 14 healthy lambs, with negative fecal exam for parasites, were to carry out the present study. They were divided into two groups, composed by seven animals: Group A represented the healthy animals (uninfected), while in Group B the animals were infected with 15,000 larvae of H. contortus. Blood was drawn on the days 15, 45 and 75 post-infection (PI) in order to perform the hematological analysis, as well as the mensuration of E-ADA activity in erythrocytes. Parasitological stool exam were performed on the same days mentioned above to follow up the evolution of the infection, as well to determine the number of eggs per gram of feces (EPG). On day 15PI, the animals presented negative EPG and there was not significant (P>0.05) difference between groups in relation to E-ADA activity and hematologic parameters. Animals in Group B had positive EPG for helminths on days 45 and 75 PI, accompanied by varying degrees of anemia, when compared to Group A. At the same periods E-ADA activity was significantly (PADA in erythrocytes and hematocrit on days 45 (r = -0.76) and 75 (r = -0.85)PI. Based on these results and in the scientific literature, it is possible to conclude that the E-ADA may participate on mechanisms related with the pathogenesis and host response against anemia caused by H. contortus. Copyright © 2013 Elsevier Ltd. All rights reserved.

  8. Effect of photodynamic therapy (PDT) on Enterococcus faecalis biofilm in experimental primary and secondary endodontic infections.

    Science.gov (United States)

    Tennert, Christian; Feldmann, Katharina; Haamann, Edwina; Al-Ahmad, Ali; Follo, Marie; Wrbas, Karl-Thomas; Hellwig, Elmar; Altenburger, Markus J

    2014-11-04

    To determine the antibacterial effect of photodynamic Therapy on Enterococcus faecalis (E. faecalis) biofilms in experimentally infected human root canals in primary infections and endodontic retreatments. One hundred and sixty single-rooted extracted teeth with one root canal were prepared using ProTaper instruments. Seventy specimens were left without root canal filling and autoclaved. The root canals of another 70 specimens were filled with Thermafil and AH Plus and the root canal fillings were removed after 24 hours using ProTaper D files and plasma sterilized. The specimens were infected with a clinical isolate of E. faecalis for 72 hours. Samples were taken using sterile paper points to determine the presence of E. faecalis in the root canals. The specimens were randomly divided into groups according to their treatment with 20 teeth each and a control. In the PDT group the teeth were treated using PDT, consisting of the photosensitizer toluidine blue and the PDT light source at 635 nm. In the NaOCl (sodium hypochlorite) group the root canals were rinsed with 10 mL of 3% NaOCl. In the NaOCl-PDT group the root canals were rinsed with 10 mL of 3% of sodium hypochlorite and then treated with PDT. Samples were taken after treatments using sterile paper points. Additionally, remaining root canal filling material was recovered from the root canal walls. Survival fractions of the samples were calculated by counting colony-forming units. A one-way analysis of variance (ANOVA) was applied to the data to assess the effect of different treatment techniques. Antimicrobial treatment of root canals caused a significant reduction of bacterial load in all groups. NaOCl irrigation eliminated E. faecalis most effectively. PDT alone was less effective compared to NaOCl irrigation and the combination of NaOCl irrigation and PDT. CFU levels recovered from the filling material after NaOCl irrigation of the root canals were 10fold higher compared to PDT and the combination of Na

  9. Humoral immune responses of experimentally Eimeria ninakholyakimovae-infected goat kids.

    Science.gov (United States)

    Matos, Lorena; Muñoz, María Del Carmen; Molina, José Manuel; Ferrer, Otilia; Rodríguez, Francisco; Pérez, Davinia; López, Adassa María; Martín, Sergio; Hermosilla, Carlos; Taubert, Anja; Ruiz, Antonio

    2017-04-01

    Although cellular immune reactions seem to be crucial for protective immune responses in Eimeria spp. infections, there are also evidences on an active involvement of the humoral counterpart. In the present study, we have analyzed the humoral response of goat kids subjected to primary and challenge infections with Eimeria ninakholyakimovae. Specific levels of IgG and IgM in serum samples and IgA in the ileal mucus were estimated. In infected kids, significantly increased levels of IgG were observed from 3 weeks post infection onwards in addition to an enhancement of specific IgM and secretory IgA levels. A wide range of peptides of sporulated oocyst antigen (SOA) was recognized by specific IgG as determined by immunoblotting. However, no correlations were found between immunoglobulin levels and OPG counts after challenge infection. Overall, these data indicate a significant specific humoral response of E. ninakohlyakimovae-infected goat kids that does not seem to convey immunoprotection. Further studies should be addressed to clarify if the lack of correlation might be associated to the type of antigen used for the immunoenzimatic assays, the age of the animals or other factors. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. Chicken line-dependent mortality after experimental infection with three type IIxIII recombinant Toxoplasma gondii clones.

    Science.gov (United States)

    Schares, G; Herrmann, D C; Maksimov, P; Matzkeit, B; Conraths, F J; Moré, G; Preisinger, R; Weigend, S

    2017-09-01

    Three genetically different clones of Toxoplasma gondii, also different in mouse virulence, were studied by experimental infection in chickens. For the experiments, four chicken lines were used, which differed in phylogenetic origin and performance level: two white egg layer lines, one with high laying performance (WLA), one with low (R11) and two brown layer lines, also displaying high (BLA) and low (L68) egg number. Chickens were intraperitoneally infected with three different T. gondii isolates representing type IIxIII recombinant clones, i.e. showing both, type II- and type III-specific alleles. These clones (K119/2 2C10, B136/1 B6H6, K119/2 A7) had exhibited virulence differences in a mouse model. In chickens, a significantly higher mortality was observed in white layer lines, but not in brown layer lines, suggesting that differences in the phylogenetic background may influence the susceptibility of chickens for toxoplasmosis. In addition, antibody (IgY) levels varied in surviving chickens at 31 days post infection. While low to intermediate antibody levels were observed in white layers, intermediate to high levels were measured in brown layers. Infection with a T. gondii clone showing low chicken virulence resulted in higher antibody levels in all chicken lines compared to infection with T. gondii clones of intermediate or high chicken virulence. This was in agreement with the parasite load as determined by real-time PCR. Overall, results show that progeny resulting from natural sexual recombination of T. gondii clonal lineages, may differ in their virulence for mice and chickens. Copyright © 2016 Elsevier Inc. All rights reserved.

  11. Unveiling the oxidative metabolism of Achatina fulica (Mollusca: Gastropoda) experimentally infected to Angiostrongylus cantonensis (Nematoda: Metastrongylidae).

    Science.gov (United States)

    Tunholi-Alves, Vinícius Menezes; Tunholi, Victor Menezes; Garcia, Juberlan; Mota, Esther Maria; Castro, Rosane Nora; Pontes, Emerson Guedes; Pinheiro, Jairo

    2018-06-01

    For the first time, alterations in the oxidative metabolism of Achatina fulica experimentally infected with different parasite loads of Angiostrongylus cantonensis were determined. For this, the hemolymph activities of lactate dehydrogenase (LDH) and hexokinase and the glucose concentrations in the hemolymph, as well as the polysaccharide reserves in the digestive gland and cephalopedal mass, were assessed. Additionally, the contents of some carboxylic acids in the hemolymph of infected and uninfected snails were determined by high-performance liquid chromatography (HPLC), permitting a better understanding of the alterations related to the host's oxidative metabolism. As the main results, activation of oxidative pathways, such as the glycolytic pathway, was demonstrated in response to the increase in the activity of hexokinase. This tendency was confirmed by the decrease in the contents of glucose in the hemolymph of parasitized snails, indicating that the infection by A. cantonensis alters the host's metabolism, and that these changes are strongly influenced by the parasite load. This metabolic scenario was accompanied by activation of the anaerobic fermentative metabolism, indicated not only by an increase in the activity of (LDH), but also by a reduction of the content of pyruvic acid and accumulation of lactic acid in the hemolymph of parasitized snails. In this circumstance, maintenance of the host's redox balance occurs through activation of the fermentative pathways, and LDH plays a central role in this process. Together, the results indicate that A. cantonensis infection induces activation of the anaerobic metabolism of A. fulica, characterized not only by the accumulation of lactic acid, but also by a reduction in the pyruvic acid and oxalic acid contents in the hemolymph of the infected snails.

  12. Evaluation of 99mTc-UBI 29-41 scintigraphy for specific detection of experimental Staphylococcus aureus prosthetic joint infections

    International Nuclear Information System (INIS)

    Sarda-Mantel, Laure; Meulemans, Alain; Vrigneaud, Jean-Marc; Raguin, Olivier; Lebtahi, Rachida; Guludec, Dominique Le; Saleh-Mghir, Azzam; Welling, Mick M.; Hervatin, Florence; Martet, Genevieve; Chau, Francoise

    2007-01-01

    99m Tc-UBI 29-41 (UBI), an antimicrobial peptide, specifically targets bacteria. We tested the ability of UBI to discriminate between infected and uninfected prosthetic joints using a rabbit model previously validated. Left knee arthroplasty was performed on 20 New Zealand rabbits, then 10 7 cfu of S. aureus (n = 12) or sterile saline (n = 8) was injected into the joint. On days 9 and 20 after surgery, planar UBI scintigraphy was performed in six infected and four uninfected rabbits, 1 h and 4 h p.i. (150 MBq), on a gamma camera. Operated-to-normal knee activity ratio (ONKR) was calculated on each scintigram. Then, after sacrifice, tissue samples of both knees were counted in a gamma counter. One rabbit injected with sterile saline had cutaneous infection at sacrifice and was excluded from analysis. ONKR was higher in infected than in uninfected animals 4 h p.i. 20 days after surgery: 1.75 ± 0.48 vs 1.13 ± 0.11, p = 0.04. From 1 h to 4 h p.i., ONKR increased in 9/12 infected and 0/7 uninfected animals. According to UBI uptake intensity and kinetics, scintigraphy was truly positive in all infected cases on day 9 and in four of six infected cases on day 20. It was truly negative in two of three sterile inflamed prosthetic knees on day 9, and in all cases on day 20. Biodistribution studies revealed increased UBI uptake in periprosthetic tissues in all animals 9 days after surgery, and only in infected animals on day 20. In this experimental study, 99m Tc-UBI 29-41 scintigraphy permitted the early detection of acute prosthetic joint infection, and exclusion of infection in chronic sterile prosthetic joint inflammation. (orig.)

  13. Pseudomonas aeruginosa Biofilm Infections

    DEFF Research Database (Denmark)

    Rybtke, Morten; Hultqvist, Louise Dahl; Givskov, Michael

    2015-01-01

    Studies of biopsies from infectious sites, explanted tissue and medical devises have provided evidence that biofilms are the underlying cause of a variety of tissue-associated and implant-associated recalcitrant human infections. With a need for novel anti-biofilm treatment strategies, research...... in biofilm infection microbiology, biofilm formation mechanisms and biofilm-associated antimicrobial tolerance has become an important area in microbiology. Substantial knowledge about biofilm formation mechanisms, biofilm-associated antimicrobial tolerance and immune evasion mechanisms has been obtained...... through work with biofilms grown in in vitro experimental setups, and the relevance of this information in the context of chronic infections is being investigated by the use of animal models of infection. Because our current in vitro experimental setups and animal models have limitations, new advanced...

  14. Experimental infection in cattle: kinetics of production of IgM and IgG against bovine cysticercosis and inflammatory response

    Directory of Open Access Journals (Sweden)

    Rafaella Paola Meneguete dos Guimarães-Peixoto

    2015-04-01

    Full Text Available Bovine cysticercosis is a zoonosis that affects humans in their adult form (taeniasis and its larval is found inserted in the musculature of infected cattle (cysticerci. It is still not entirely clear how animal immune response against infection occurs, being the comprehension of this process necessary for the enhancement of diagnostic capacity and disease prevention. This work aimed to evaluate the evolution of the immune response in experimentally infected cattle, compared with findings in cell response by optical microscopy. Nine animals were infected at a rate of 120,000 eggs of Taenia saginata. Five of the animals were similar in the kinetics of antibody production against cysticerci, with maximal levels of IgG and IgM. The other four animals showed an immune response different from the majority, with two of them showing delayed response to infection by cysticerci while the others apparently did not have initial contact with antigens secreted by cysticerci. Regarding the cellular response, it was found that, in lesions of viable cysticerci, inflammatory cells predominated, whereas in nonviable cysticerci there were tissue repair cells in the most part, being possible to notice that the amount of migratory calcareous corpuscles are related to the death stage of the parasite. These findings are important for the understanding immune response of cattle infected with cysticercosis.

  15. The nonstructural proteins of Nipah virus play a key role in pathogenicity in experimentally infected animals.

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    Misako Yoneda

    Full Text Available Nipah virus (NiV P gene encodes P protein and three accessory proteins (V, C and W. It has been reported that all four P gene products have IFN antagonist activity when the proteins were transiently expressed. However, the role of those accessory proteins in natural infection with NiV remains unknown. We generated recombinant NiVs lacking V, C or W protein, rNiV(V-, rNiV(C-, and rNiV(W-, respectively, to analyze the functions of these proteins in infected cells and the implications in in vivo pathogenicity. All the recombinants grew well in cell culture, although the maximum titers of rNiV(V- and rNiV(C- were lower than the other recombinants. The rNiV(V-, rNiV(C- and rNiV(W- suppressed the IFN response as well as the parental rNiV, thereby indicating that the lack of each accessory protein does not significantly affect the inhibition of IFN signaling in infected cells. In experimentally infected golden hamsters, rNiV(V- and rNiV(C- but not the rNiV(W- virus showed a significant reduction in virulence. These results suggest that V and C proteins play key roles in NiV pathogenicity, and the roles are independent of their IFN-antagonist activity. This is the first report that identifies the molecular determinants of NiV in pathogenicity in vivo.

  16. Experimental Trypanosoma evansi infection in donkeys: hematological, biochemical and histopathological changes Infecção experimental em jumentos com Trypanosoma evansi: alterações hematológicas, bioquímicas e histopatológicas

    Directory of Open Access Journals (Sweden)

    F.A. Cadioli

    2006-10-01

    Full Text Available Five adult donkeys were experimentally infected with Brazilian strain of Trypanosoma evansi originally isolated from a naturally infected dog to study the hematological biochemical and histopathological alterations during the evolution of the disease. The course of the experimental infection was followed up to 145 days. Hematological analyses of the infected donkeys revealed a marked decline in hemoglobin, packed-cell volume, and erythrocyte count. Anemia was observed after successive peaks of parasitemia. Biochemical analyses showed increased levels of icterus index, serum globulins and decreased serum albumin and glucose values. All infected donkeys revealed enlargement of spleen and its white pulp, enlargement of mediastinal lymph nodes and lungs congestion. The main histopathological features consisted of meningoencephalitis. Demyelination in some areas of the cerebellum pediculus and neuropil vacuolization were observed. This study showed that donkeys infected with a Brazilian strain of T. evansi developed a chronic disease.Cinco jumentos, adultos foram infectados experimentalmente com cepa brasileira de Trypanosoma evansi, isolada de um cão naturalmente infectado, com o intuito de observar as alterações hematológicas, bioquímicas e histopatológicas durante a evolução da enfermidade. O curso da infecção experimental foi de 145 dias. Análise hematológica dos jumentos infectados revelou declínio nos valores de hemoglobina, hematócrito e contagem total de eritrócitos. Notou-se anemia após sucessivos picos de parasitemia. Análise bioquímica indicou aumento dos níveis de índice ictérico, globulinas séricas e diminuição dos valores séricos de albumina e glicose. Todos os jumentos infectados apresentaram aumento do baço e de sua polpa branca, aumento de linfonodos mediastínicos e congestão pulmonar. Meningoencefalite foi o principal achado histopatológico. Em algumas áreas do pedículo cerebelar foram observadas

  17. Distribution of sialic acid receptors and influenza A virus of avian and swine origin in experimentally infected pigs

    Directory of Open Access Journals (Sweden)

    Viuff Birgitte M

    2011-09-01

    Full Text Available Abstract Background Pigs are considered susceptible to influenza A virus infections from different host origins because earlier studies have shown that they have receptors for both avian (sialic acid-alpha-2,3-terminal saccharides (SA-alpha-2,3 and swine/human (SA-alpha-2,6 influenza viruses in the upper respiratory tract. Furthermore, experimental and natural infections in pigs have been reported with influenza A virus from avian and human sources. Methods This study investigated the receptor distribution in the entire respiratory tract of pigs using specific lectins Maackia Amurensis (MAA I, and II, and Sambucus Nigra (SNA. Furthermore, the predilection sites of swine influenza virus (SIV subtypes H1N1 and H1N2 as well as avian influenza virus (AIV subtype H4N6 were investigated in the respiratory tract of experimentally infected pigs using immunohistochemical methods. Results SIV antigen was widely distributed in bronchi, but was also present in epithelial cells of the nose, trachea, bronchioles, and alveolar type I and II epithelial cells in severely affected animals. AIV was found in the lower respiratory tract, especially in alveolar type II epithelial cells and occasionally in bronchiolar epithelial cells. SA-alpha-2,6 was the predominant receptor in all areas of the respiratory tract with an average of 80-100% lining at the epithelial cells. On the contrary, the SA-alpha-2,3 was not present (0% at epithelial cells of nose, trachea, and most bronchi, but was found in small amounts in bronchioles, and in alveoli reaching an average of 20-40% at the epithelial cells. Interestingly, the receptor expression of both SA-alpha-2,3 and 2,6 was markedly diminished in influenza infected areas compared to non-infected areas. Conclusions A difference in predilection sites between SIV and AIV virus was found, and this difference was in accordance with the distribution of the SA-alpha-2,6 and SA-alpha-2,3 receptor, respectively. The results indicated

  18. Experimental Oral Herpes Simplex Virus-1 (HSV-1 Co-infection in Simian Immunodeficiency Virus (SIV-Infected Rhesus Macaques

    Directory of Open Access Journals (Sweden)

    Meropi Aravantinou

    2017-12-01

    Full Text Available Herpes simplex virus 1 and 2 (HSV-1/2 similarly initiate infection in mucosal epithelia and establish lifelong neuronal latency. Anogenital HSV-2 infection augments the risk for sexual human immunodeficiency virus (HIV transmission and is associated with higher HIV viral loads. However, whether oral HSV-1 infection contributes to oral HIV susceptibility, viremia, or oral complications of HIV infection is unknown. Appropriate non-human primate (NHP models would facilitate this investigation, yet there are no published studies of HSV-1/SIV co-infection in NHPs. Thus, we performed a pilot study for an oral HSV-1 infection model in SIV-infected rhesus macaques to describe the feasibility of the modeling and resultant immunological changes. Three SIV-infected, clinically healthy macaques became HSV-1-infected by inoculation with 4 × 108 pfu HSV-1 McKrae on buccal, tongue, gingiva, and tonsils after gentle abrasion. HSV-1 DNA was shed in oral swabs for up to 21 days, and shedding recurred in association with intra-oral lesions after periods of no shedding during 56 days of follow up. HSV-1 DNA was detected in explant cultures of trigeminal ganglia collected at euthanasia on day 56. In the macaque with lowest baseline SIV viremia, SIV plasma RNA increased following HSV-1 infection. One macaque exhibited an acute pro-inflammatory response, and all three animals experienced T cell activation and mobilization in blood. However, T cell and antibody responses to HSV-1 were low and atypical. Through rigorous assessesments, this study finds that the virulent HSV-1 strain McKrae resulted in a low level HSV-1 infection that elicited modest immune responses and transiently modulated SIV infection.

  19. Gastrointestinal trichostrongylosis can predispose ewes to clinical mastitis after experimental mammary infection.

    Science.gov (United States)

    Mavrogianni, V S; Papadopoulos, E; Gougoulis, D A; Gallidis, E; Ptochos, S; Fragkou, I A; Orfanou, D C; Fthenakis, G C

    2017-10-15

    Objective was to study, in an experimental model, the possible role of gastrointestinal nematode infection in predisposing ewes to mastitis during the lactation period. Twenty-four ewes (A or B [n=12]), free from nematode and trematode helminths, were used. Group A animals received 5000 third-stage larvae of a trichostrongylid helminth cocktail and group B ewes were unparasitised controls. Animals in group A developed gastrointestinal trichostrongylosis confirmed by >500epg in faecal samples; mean epg of group B ewes were Ewes were challenged by deposition of Mannheimia haemolytica into the teat duct. In group A, 7 ewes developed clinical and 5 subclinical mastitis; no ewe in group B developed clinical mastitis, but only subclinical (12 ewes) (P=0.002). M. haemolytica was isolated from 132/132 and 121/132 udder samples from group A or B, respectively (Pewes that developed clinical mastitis than in others which did not (0.709 and 0.162 versus 0.662 and 0.136, respectively; Pewes with subclinical mastitis (in group A or B), inducible-lymphoid-follicles were observed in the teat, which were not observed in ewes with clinical disease. Total pathology scores summed over all days were 127 and 73 for group A or B ewes, respectively (maximum possible 192; Pewes that developed clinical mastitis. It is concluded that, in view of bacterial challenge, gastrointestinal trichostrongylosis and particularly Teladorsagia infection, might lead to clinical mastitis, through various pathogenetic pathways. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. Is Salvage of Recently Infected Breast Implant After Breast Augmentation or Reconstruction Possible? An Experimental Study.

    Science.gov (United States)

    Castus, P; Heymans, O; Melin, P; Renwart, L; Henrist, C; Hayton, E; Mordon, S; Leclère, F M

    2018-04-01

    The reinsertion of an infected implant when peri-prosthetic infection occurs early after breast augmentation or breast reconstruction remains controversial. In this experimental study, the authors tried to remove bacteria, and their biofilm, from the colonized surface of breast prostheses, without damaging their integrity. A total of 112 shell samples of silicone breast prostheses, smooth (SPSS) and textured (TPSS), were colonized by S. epidermidis (SE) or S. aureus (SA) strains, all able to produce biofilms. After 15 days, all the samples were removed from the contaminated culture broth and constituted 4 groups of 20 contaminated samples: SPSS/SE (group I), SPSS/SA (group II), TPSS/SE (group III), TPSS/SE (group IV). In another group-group SEM-, 16 colonized samples were used for documentation with scanning electron microscopy (SEM). The remaining 16 samples were used to test the limits of detection of the sterility test. All samples of groups I-IV and 8 samples of group SEM were « washed » with a smooth brush in a povidone-iodine bath and rinsed with saline solution. A subset of the washed samples was sent for SEM and the others were immersed in sterile broth and were incubated at 35 °C for 3 weeks (groups I-IV). Fifteen days after contamination, all the samples in groups I-IV were colonized. In the SEM group, SEM images attested to the presence of bacteria in biofilm attached to the shells. After cleaning, SEM did not reveal any bacteria and there was no visible alteration in the outer structure of the shell. Sterility tests performed after decontamination in groups I-IV remained negative for all the samples. Breast prostheses recently contaminated with Staphylococci, frequently involved in peri-prosthetic breast implant infection and capable of producing biofilms, can be efficiently decontaminated by the procedure used in this study. Our decontamination procedure did not alter the surface structure of the prostheses. This decontamination procedure

  1. FSL-1, a bacterial-derived toll-like receptor 2/6 agonist, enhances resistance to experimental HSV-2 infection

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    Pyles Richard B

    2009-11-01

    Full Text Available Abstract Background Herpes simplex virus type 2 (HSV-2 is a leading cause of genital ulceration that can predispose individuals to an increased risk of acquiring other sexually transmitted infections. There are no approved HSV-2 vaccines and current suppressive therapies require daily compound administration that does not prevent all recurrences. A promising experimental strategy is the use of toll-like receptor (TLR agonists to induce an innate immune response that provides resistance to HSV-2 infection. Previous studies showed that anti-herpetic activity varied based on origin of the agonists and activation of different TLR indicating that activity likely occurs through elaboration of a specific innate immune response. To test the hypothesis, we evaluated the ability of a bacterial-derived TLR2/6 agonist (FSL-1 to increase resistance to experimental genital HSV-2 infection. Methods Vaginal application of FSL-1 at selected doses and times was evaluated to identify potential increased resistance to genital HSV-2 infection in the mouse model. The FSL-1 induced cytokine profile was quantified using kinetically collected vaginal lavages. Additionally, cytokine elaboration and organ weights were evaluated after single or multiple FSL-1 doses to establish a preliminary safety profile. Human vaginal EC cultures were used to confirm the mouse model outcomes. Results The results showed that vaginally-applied FSL-1 created an environment resistant to a 25-fold higher HSV-2 challenge dose. Mechanistically, vaginal FSL-1 application led to transient elaboration of cytokines linked to anti-herpetic innate immune responses. No gross local or peripheral immunotoxicity was observed even after multiple dosing. FSL-1 also created an anti-herpetic environment in cultures of human vaginal epithelial cells (EC. Conclusion The results showed, for the first time, that the bacterial-derived TLR2/6 agonist FSL-1 induced significant resistance to HSV-2 infection when

  2. Experimental canine distemper infection as a means of demonstrating latent effects of subacute lead intoxication

    Energy Technology Data Exchange (ETDEWEB)

    White, D.J.; McLeod, S.

    1976-01-01

    Observations on the response of the body to experimental infection with distemper virus in dogs previously dosed subacutely with lead have demonstrated a latent effect of lead on several body systems. Effects which indicated a relationship to earlier treatment with lead included evidence for stimulation of haemoglobin synthesis, changes to red blood cells resulting in increased destruction, increased vulnerability of the parenchymatous cells of the liver to damage, reduction in the weight of the skeleton and thyroid, an increase in weight of the thymus and brain and histopathological changes in the thymus. 21 references, 2 figures, 1 table.

  3. Adaptation of Lymnaea fuscus and Radix balthica to Fasciola hepatica through the experimental infection of several successive snail generations

    Science.gov (United States)

    2014-01-01

    Background High prevalence of Fasciola hepatica infection (>70%) was noted during several outbreaks before the 2000s in several French farms where Galba truncatula is lacking. Other lymnaeids such as Lymnaea fuscus, L. glabra and/or Radix balthica are living in meadows around these farms but only juvenile snails can sustain complete larval development of F. hepatica while older snails were resistant. The low prevalence of infection (<20%) and limited cercarial production (<50 cercariae per infected snail) noted with these juveniles could not explain the high values noted in these cattle herds. As paramphistomosis due to Calicophoron daubneyi was not still noted in these farms, the existence of another mode of infection was hypothesized. Experimental infection of several successive generations of L. glabra, originating from eggs laid by their parents already infected with this parasite resulted in a progressive increase in prevalence of snail infection and the number of shed cercariae. The aim of this paper was to determine if this mode of snail infection was specific to L. glabra, or it might occur in other lymnaeid species such as L. fuscus and R. balthica. Methods Five successive generations of L. fuscus and R. balthica were subjected to individual bimiracidial infections in the laboratory. Resulting rediae and cercariae in the first four generations were counted after snail dissection at day 50 p.e. (20°C), while the dynamics of cercarial shedding was followed in the F5 generation. Results In the first experiment, prevalence and intensity of F. hepatica infection in snails progressively increased from the F1 (R. balthica) or F2 (L. fuscus) generation. In the second experiment, the prevalence of F. hepatica infection and the number of shed cercariae were significantly lower in L. fuscus and R. balthica (without significant differences between both lymnaeids) than in G. truncatula. Conclusion The F. hepatica infection of several successive snail generations

  4. The Haemophilus ducreyi trimeric autotransporter adhesin DsrA protects against an experimental infection in the swine model of chancroid.

    Science.gov (United States)

    Fusco, William G; Choudhary, Neelima R; Routh, Patty A; Ventevogel, Melissa S; Smith, Valerie A; Koch, Gary G; Almond, Glen W; Orndorff, Paul E; Sempowski, Gregory D; Leduc, Isabelle

    2014-06-24

    Adherence of pathogens to cellular targets is required to initiate most infections. Defining strategies that interfere with adhesion is therefore important for the development of preventative measures against infectious diseases. As an adhesin to host extracellular matrix proteins and human keratinocytes, the trimeric autotransporter adhesin DsrA, a proven virulence factor of the Gram-negative bacterium Haemophilus ducreyi, is a potential target for vaccine development. A recombinant form of the N-terminal passenger domain of DsrA from H. ducreyi class I strain 35000HP, termed rNT-DsrAI, was tested as a vaccine immunogen in the experimental swine model of H. ducreyi infection. Viable homologous H. ducreyi was not recovered from any animal receiving four doses of rNT-DsrAI administered with Freund's adjuvant at two-week intervals. Control pigs receiving adjuvant only were all infected. All animals receiving the rNT-DsrAI vaccine developed antibody endpoint titers between 3.5 and 5 logs. All rNT-DsrAI antisera bound the surface of the two H. ducreyi strains used to challenge immunized pigs. Purified anti-rNT-DsrAI IgG partially blocked binding of fibrinogen at the surface of viable H. ducreyi. Overall, immunization with the passenger domain of the trimeric autotransporter adhesin DsrA accelerated clearance of H. ducreyi in experimental lesions, possibly by interfering with fibrinogen binding. Copyright © 2014 Elsevier Ltd. All rights reserved.

  5. Dynamics of Pathological and Virological Findings During Experimental Calpox Virus Infection of Common Marmosets (Callithrix jacchus

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    Anne Schmitt

    2017-11-01

    Full Text Available Experimental intranasal infection of marmosets (Callithrix jacchus with calpox virus results in fatal disease. Route and dose used for viral inoculation of the test animals mimics the natural transmission of smallpox, thus representing a suitable model to study pathogenesis and to evaluate new vaccines against orthopoxvirus infection. However, the pathogenic mechanisms leading to death are still unclear. Therefore, our study aimed at investigating the kinetics of pathological alterations to clarify the pathogenesis in calpox virus infection. Following intranasal inoculation with two different viral doses, common marmosets were sacrificed on days 3, 5, 7, 10 and 12 post inoculation. Collected tissue was screened using histopathology, immunohistochemistry, transmission electron microscopy, and virological assays. Our data suggest that primary replication took place in nasal and bronchial epithelia followed by secondary replication in submandibular lymph nodes and spleen. Parallel to viremia at day 7, virus was detectable in many organs, mainly located in epithelial cells and macrophages, as well as in endothelial cells. Based on the onset of clinical signs, the histological and ultrastructural lesions and the immunohistochemical distribution pattern of the virus, the incubation period was defined to last 11 days, which resembles human smallpox. In conclusion, the data indicate that the calpox model is highly suitable for studying orthopoxvirus-induced disease.

  6. Pharmacokinetic/Pharmacodynamic Profiles of Tiamulin in an Experimental Intratracheal Infection Model of Mycoplasma gallisepticum.

    Science.gov (United States)

    Xiao, Xia; Sun, Jian; Yang, Tao; Fang, Xi; Cheng, Jie; Xiong, Yan Q; Liu, Ya-Hong

    2016-01-01

    Mycoplasma gallisepticum is the most important pathogen in poultry among four pathogenic Mycoplasma species. Tiamulin is a pleuromutilin antibiotic that shows a great activity against M. gallisepticum and has been approved for use in veterinary medicine particularly for poultry. However, the pharmacokinetic/pharmacodynamics (PK/PD) profiles of tiamulin against M. gallisepticum are not well understood. Therefore, in the current studies, we investigated the in vivo PK/PD profiles of tiamulin using a well-established experimental intratracheal infection model of M. gallisepticum. The efficacy of tiamulin against M. gallisepticum was studied in 8-day-old chickens after intramuscular (i.m.) administration at 10 doses between 0-80 mg/kg. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) was used to evaluate the PK parameters of tiamulin following i.m. administration at doses of 5, 40, and 80 mg/kg in Mycoplasma gallisepticum-infected neutropenic chickens. Real-time PCR (RT-PCR) was used for quantitative detection of M. gallisepticum. The MIC of tiamulin against M. gallisepticum strain S6 was 0.03 μg/mL. The PK/PD index, AUC24h/MIC, correlated well with the in vivo antibacterial efficacy. The in vivo data suggest that animal dosage regimens should supply AUC24h/MIC of tiamulin of 382.68 h for 2 log10 ccu equivalents M. gallisepticum reduction. To attain that goal, the administered dose is expected to be 45 mg/kg b.w. for treatment of M. gallisepticum infection with an MIC90 of 0.03 μg/mL.

  7. Pharmacokinetic/Pharmacodynamic Profiles of Tiamulin in an Experimental Intratracheal Infection Model of Mycoplasma gallisepticum

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    Xia Xiao

    2016-09-01

    Full Text Available Mycoplasma gallisepticum is the most important pathogen in poultry among four pathogenic Mycoplasma species. Tiamulin is a pleuromutilin antibiotic that shows a great activity against M. gallisepticum and has been approved for use in veterinary medicine particularly for poultry. However, the Pharmacokinetic/Pharmacodynamics (PK/PD profiles of tiamulin against M. gallisepticum are not well understood. Therefore, in the current studies, we investigated the in vivo PK/PD profiles of tiamulin using a well-established experimental intratracheal infection model of M. gallisepticum. The efficacy of tiamulin against M. gallisepticum was studied in 8-day-old chickens after intramuscular (i.m. administration at 10 doses between 0-80 mg/kg. Liquid chromatography-tandem mass spectrometry (LC-MS/MS was used to evaluate the PK parameters of tiamulin following i.m. administration at doses of 5, 40 and 80 mg/kg in Mycoplasma gallisepticum infected neutropenic chickens. Real time PCR (RT-PCR was used for quantitative detection of M. gallisepticum. The MIC of tiamulin against M. gallisepticum strain S6 was 0.03 μg/mL. The PK/PD index, AUC24h/MIC, correlated well with the in vivo antibacterial efficacy. The in vivo data suggest that animal dosage regimens should supply AUC24h/MIC of tiamulin of 382.68 h for 2 log10 ccu equivalents M. gallisepticum reduction. To attain that goal, the administered dose is expected to be 45 mg/kg b.w. for treatment of M. gallisepticum infection with an MIC90 of 0.03 μg/mL.

  8. Cranial joint histology in the mallard duck (Anas platyrhynchos): new insights on avian cranial kinesis.

    Science.gov (United States)

    Bailleul, Alida M; Witmer, Lawrence M; Holliday, Casey M

    2017-03-01

    The evolution of avian cranial kinesis is a phenomenon in part responsible for the remarkable diversity of avian feeding adaptations observable today. Although osteological, developmental and behavioral features of the feeding system are frequently studied, comparatively little is known about cranial joint skeletal tissue composition and morphology from a microscopic perspective. These data are key to understanding the developmental, biomechanical and evolutionary underpinnings of kinesis. Therefore, here we investigated joint microstructure in juvenile and adult mallard ducks (Anas platyrhynchos; Anseriformes). Ducks belong to a diverse clade of galloanseriform birds, have derived adaptations for herbivory and kinesis, and are model organisms in developmental biology. Thus, new insights into their cranial functional morphology will refine our understanding of avian cranial evolution. A total of five specimens (two ducklings and three adults) were histologically sampled, and two additional specimens (a duckling and an adult) were subjected to micro-computed tomographic scanning. Five intracranial joints were sampled: the jaw joint (quadrate-articular); otic joint (quadrate-squamosal); palatobasal joint (parasphenoid-pterygoid); the mandibular symphysis (dentary-dentary); and the craniofacial hinge (a complex flexion zone involving four different pairs of skeletal elements). In both the ducklings and adults, the jaw, otic and palatobasal joints are all synovial, with a synovial cavity and articular cartilage on each surface (i.e. bichondral joints) ensheathed in a fibrous capsule. The craniofacial hinge begins as an ensemble of patent sutures in the duckling, but in the adult it becomes more complex: laterally it is synovial; whereas medially, it is synostosed by a bridge of chondroid bone. We hypothesize that it is chondroid bone that provides some of the flexible properties of this joint. The heavily innervated mandibular symphysis is already fused in the

  9. An experimental in-vivo canine model for adult shunt infection

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    Procop Gary

    2008-10-01

    Full Text Available Abstract Background Detailed human studies of the mechanisms and development of shunt infection in real time are not possible, and we have developed a canine hydrocephalus model to overcome this. The intention of this pilot study was to show that the canine hydrocephalus model could be shunted using conventional "human" shunts, and that a shunt infection could be established so that further studies could then be planned. Methods Hydrocephalus was induced in seven dogs (Canis familiaris by fourth ventricle obstruction. Four weeks later they were shunted using a Hakim Precision valve. Four of the dogs received shunts whose ventricular catheter had been inoculated with Staphylococcus epidermidis, and three were uninoculated controls. Four weeks after shunting the dogs were sacrificed and necropsy was performed. Removed shunts and tissue samples were examined microbiologically and isolates were subjected to detailed identification and genomic comparison. Results All the dogs remained well after shunting. Examination of removed shunt components revealed S. epidermidis in the brain and throughout the shunt system in the four inoculated animals, but in two of these Staphylococcus intermedius was also found. S. intermedius was also isolated from all three "negative" controls. There were slight differences between S. intermedius strains suggesting endogenous infection rather than cross- infection from a point source. Conclusion Shunt infection was established in the canine model, and had the experiment been extended beyond four weeks the typical microbiological, pathological and clinical features might have appeared. The occurrence of unplanned shunt infections in control animals due to canine normal skin flora reflects human clinical experience and underlines the usual source of bacteria causing shunt infection.

  10. The porcine acute phase protein response to acute clinical and subclinical experimental infection with Streptococcus suis

    DEFF Research Database (Denmark)

    Sørensen, Nanna Skall; Tegtmeier, C.; Andresen, Lars Ole

    2006-01-01

    The pig acute phase protein (APP) response to experimental Streptococcus suis (S. suis) infection was mapped by the measurement of the positive APPs C-reactive protein (CRP), serum amyloid A (SAA), haptoglobin (Hp) and major acute phase protein (pig-MAP) and the negative APPs albumin...... and apolipoprotein (Apo) A-I. The aim was to elucidate the differences in the acute phase behaviour of the individual APPs during a typical bacterial septicaemic, infection. Pigs were inoculated subcutaneously with live S. suis serotype 2 and blood was sampled before and on various days post inoculation (p...... the experiment with maximum levels around 10 times the day 0-levels, and pig-MAP was elevated on days 1-12 p.i. with peak levels of around seven times the day 0-levels. Apo A-I was decreased from days 1 to 8 and showed minimum levels of about 40% of day 0-levels around 1-2 days p.i. No clear pattern of changes...

  11. Growth performance of broilers in experimental Reovirus infections

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    Sudhakar P. Awandkar

    Full Text Available Background: The avian reoviruses have emerged to induce various manifestations in chickens. They are associated with disease conditions including malabsorption syndrome, tenosynovitis etc. Reoviruses are an important cause of suboptimum performance in broilers, resulting in poor growth performance. Poultry industry in India is facing a catastrophe due to such infections which go unnoticed in field due to masking of the symptoms by secondary infections and commonly observed nutritional disorders. Aim: To investigate the effect of reovirus infection on overall performance of broiler birds. Material and Methods: The broiler birds were challenged with homologous strains of malabsorption syndrome and tenosynovitis syndrome of reovirus. The growth performance was recorded. Results and conclusion: The growth performance and immune response to NDV did not differ in the birds challenged with tenosynovitis syndrome strain of reo virus as compared to un challenged birds. However, poor live body weight, feed intake, FCR, PE and BPEI and better serum NDV titres were found in chicks challenged with malabsorption syndrome strain of reovirus as compared to the chicks from control group. [Vet World 2012; 5(11.000: 685-689

  12. Neural Damage in Experimental Trypanosoma brucei gambiense Infection: The Suprachiasmatic Nucleus

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    Chiara Tesoriero

    2018-02-01

    Full Text Available Trypanosoma brucei (T. b. gambiense is the parasite subspecies responsible for most reported cases of human African trypanosomiasis (HAT or sleeping sickness. This severe infection leads to characteristic disruption of the sleep-wake cycle, recalling attention on the circadian timing system. Most animal models of the disease have been hitherto based on infection of laboratory rodents with the T. b. brucei subspecies, which is not infectious to humans. In these animal models, functional, rather than structural, alterations of the master circadian pacemaker, the hypothalamic suprachiasmatic nucleus (SCN, have been reported. Information on the SCN after infection with the human pathogenic T. b. gambiense is instead lacking. The present study was aimed at the examination of the SCN after T. b. gambiense infection of a susceptible rodent, the multimammate mouse, Mastomys natalensis, compared with T. b. brucei infection of the same host species. The animals were examined at 4 and 8 weeks post-infection, when parasites (T. b. gambiense or T. b. brucei were detected in the brain parenchyma, indicating that the disease was in the encephalitic stage. Neuron and astrocyte changes were examined with Nissl staining, immunophenotyping and quantitative analyses. Interestingly, significant neuronal loss (about 30% reduction was documented in the SCN during the progression of T. b. gambiense infection. No significant neuronal density changes were found in the SCN of T. b. brucei-infected animals. Neuronal cell counts in the hippocampal dentate gyrus of T. b. gambiense-infected M. natalensis did not point out significant changes, indicating that no widespread neuron loss had occurred in the brain. Marked activation of astrocytes was detected in the SCN after both T. b. gambiense and T. b. brucei infections. Altogether the findings reveal that neurons of the biological clock are highly susceptible to the infection caused by human pathogenic African trypanosomes

  13. Comparative Response of the West African Dwarf Goats to Experimental Infections with Red Sokoto and West African Dwarf Goat Isolates of Haemonchus contortus

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    Lucas Atehmengo Ngongeh

    2015-01-01

    Full Text Available Response of the West African Dwarf (WAD goats to two different isolates of Haemonchus contortus, the Red Sokoto (RS goat isolate (RSHc and the WAD goat isolate (WADHc (isolated from WAD goats, was studied by experimental infections of 4–6-month-old male WAD goat kids. Group 1 and Group 2 goats were each infected with 4500 infective larvae (L3 of RSHc and WADHc, respectively. Group 3 animals served as uninfected control. Prepatent period (PPP, faecal egg counts (FEC, worm burden (WB, body weight (BW, packed cell volume (PCV, and body condition score (BCS were determined. WAD goats infected with RSHc isolate and the ones infected with WADHc isolate had mean PPP of 19.63±0.26 and 19.50±0.19, respectively. Goats infected with WADHc isolate had significantly higher FEC (P=0.004 and WB (P=0.001. BW were significantly higher (P=0.004 both in the controls and in Group 2 goats infected with WADHc isolate than in Group 1 goats infected with the RSHc isolate. BCS of animals in both infected groups dropped significantly (P=0.001. There was a significant drop in PCV (P=0.004 of both infected groups in comparison. Both isolates of H. contortus were pathogenic to the host.

  14. Comparative Response of the West African Dwarf Goats to Experimental Infections with Red Sokoto and West African Dwarf Goat Isolates of Haemonchus contortus.

    Science.gov (United States)

    Ngongeh, Lucas Atehmengo; Onyeabor, Amaechi

    2015-01-01

    Response of the West African Dwarf (WAD) goats to two different isolates of Haemonchus contortus, the Red Sokoto (RS) goat isolate (RSHc) and the WAD goat isolate (WADHc) (isolated from WAD goats), was studied by experimental infections of 4-6-month-old male WAD goat kids. Group 1 and Group 2 goats were each infected with 4500 infective larvae (L3) of RSHc and WADHc, respectively. Group 3 animals served as uninfected control. Prepatent period (PPP), faecal egg counts (FEC), worm burden (WB), body weight (BW), packed cell volume (PCV), and body condition score (BCS) were determined. WAD goats infected with RSHc isolate and the ones infected with WADHc isolate had mean PPP of 19.63 ± 0.26 and 19.50 ± 0.19, respectively. Goats infected with WADHc isolate had significantly higher FEC (P = 0.004) and WB (P = 0.001). BW were significantly higher (P = 0.004) both in the controls and in Group 2 goats infected with WADHc isolate than in Group 1 goats infected with the RSHc isolate. BCS of animals in both infected groups dropped significantly (P = 0.001). There was a significant drop in PCV (P = 0.004) of both infected groups in comparison. Both isolates of H. contortus were pathogenic to the host.

  15. Effect of overwintering on the frequency of flies infected by the rhabdovirus sigma in experimental populations of Drosophila melanogaster.

    Science.gov (United States)

    Fleuriet, A

    1981-01-01

    Artificial overwintering, assuming that adulthood is the overwintering stage, has been performed on six experimental populations of Drosophila melanogaster. In five of them, the frequency of flies infected by the hereditary Rhabdovirus sigma is always in the first spring generation than it was in the last generation of the preceding fall. This result might indicate a higher sensitivity of infected flies to winter conditions, but other interpretations, connected with the genes for resistance to the virus might be considered. In one of the six populations, no effect was detected after any of the three successive winters. It appears therefore that the genetic background of the flies or/and of the propagated virus intervenes in the response to overwintering.

  16. Anorexia in rats infected with the nematode, Nippostrongylus brasiliensis: experimental manipulations.

    Science.gov (United States)

    Mercer, J G; Mitchell, P I; Moar, K M; Bissett, A; Geissler, S; Bruce, K; Chappell, L H

    2000-06-01

    Nippostrongylus brasiliensis induces a biphasic anorexia in laboratory rats, the first phase coincident with lung invasion (ca day 2) and the second when the worms mature in the intestine (ca day 8). Using the anthelminthic, mebendazole (MBZ), N. brasiliensis infections of the rat were eliminated between the first and second anorexic episodes. This intervention prevented the expression of the second phase of anorexia. Rats exposed to a second infection with N. brasiliensis, 3 weeks after the primary infection, exhibited only a first phase anorexic response which was not influenced by MBZ termination of the primary infection. The lower cumulative food intake and weight gain of all infected rats after 8 days of infection were accompanied by elevated plasma insulin and, in some individuals, by elevated plasma leptin, compared with uninfected controls and previously-infected MBZ-treated rats. Messenger RNA levels for neuropeptide Y were higher in the hypothalamic arcuate nucleus of 8-day infected rats than in recovering MBZ-treated animals. Inoculation of rats with heat-killed N. brasiliensis larvae failed to induce anorexia and did not alter the severity of biphasic anorexia on subsequent injection of viable larvae. The first anorexic episode is therefore dependent upon viable migrating larvae. The second phase of anorexia clearly requires the continuing presence of the parasite beyond the lung phase. Viable migrating larvae are also required to confer 'resistance' to reinfection.

  17. Aspects of resistance to experimental infection with Trypanosoma cruzi; Aspectos da resistencia a infecao experimental com Trypanosoma cruzi

    Energy Technology Data Exchange (ETDEWEB)

    Dias, Viviane Liotti

    2010-07-01

    Chagas disease, a zoonosis caused by the protozoan Trypanosoma cruzi, has a wide distribution in Latin America and extends from the southern part of the United States to Argentina. A number of 10 million of infected people is estimated and another 25 million exposed to the risk. Although discovered over a century, Chagas disease is still a serious infection that causes great socioeconomic impact, with no effective treatment at the chronic phase and in which, a lack of scientific knowledge can be observed. The main goal of this work was that obtaining and using consomic strain of mice, the resistance could be investigated. Consomic strains were produced by programmed mating, in which the animals were monitored with DNA polymorphic markers, and one of his chromosomes was replaced by his homologue from another strain. As parental, were used, the inbred strains C57BL/6/J Unib with resistant phenotype (donor) and as receiver, the A/JUnib strain, that has a susceptible phenotype. These models were used to produce five consomic strains: for the chromosomes 7 (CSs7), 11 (CSs11), 14 (CSs14), 17 (CSs17) and 19 (CSs19), described by Passos et al. (2003) as important in controlling infection caused by the Y strain of T. cruzi. In experimental testing, the consomics were inoculated intraperitoneally at doses of 10{sup 1}, 10{sup 2}, 10{sup 3} and 10{sup 4} using as control, animals from both parental lines. In all consomics, resistance was higher than that observed in the susceptible parental. In a second protocol, the consomics were mated with scheduled associations and the progenies were challenged with inocula employing increasing doses of trypomastigotes. The resistance observed in this group was also higher than that observed in the parental with susceptible phenotype. The observed results demonstrate that the use of the consomic strains that were produced order to assess the contribution of each chromosome in the resistance, as well as the effects of association between

  18. Ketoconazole modulates the infectivity of Ichthyophonus sp. (Mesomycetozoa) in vivo in experimentally injected European sea bass.

    Science.gov (United States)

    Hontoria, Francisco; González, Ma Angeles; Sitjà-Bobadilla, Ariadna; Palenzuela, Oswaldo; Alvarez-Pellitero, Pilar

    2013-09-03

    In vitro studies have confirmed the inhibitory effect of the azol-derivative ketoconazole (KZ) on the growth of Ichthyophonus, an important pathogen causing epizootics in wild and cultured fish. We evaluated the effect of KZ in vivo in European sea bass Dicentrarchus labrax experimentally infected with the same Ichthyophonus isolate. Liposomes were used to vehiculate different doses of KZ to increase the effect on Ichthyophonus and lower the toxicity of the drug, and KZ toxicity was assessed in cultured sea bass juveniles. We also studied the effect of liposome-vehiculated KZ included in medicated food on ichthyophoniasis. KZ causes clear toxic effects in D. labrax juveniles at doses >80 mg kg-1, apparent in the reduced survival of fish and histological alterations to livers, kidneys and spleens. Fish injected with Ichthyophonus and treated with KZ dosages of ≤80 mg kg-1 d-1 presented lower ichthyophoniasis prevalence, fewer organs infected per fish, and fewer spores in the affected organs than the untreated fish. KZ seems to delay the onset of infection, but cannot stop further progression once established. However, this behaviour is not clearly reflected in the biometric and haematological data collected from these fish. We hypothesise that KZ's delaying effect would increase, if lower infective doses (more similar to natural situations) were used. The drug administration vehicle (liposomes vs. emulsions) did not affect the results. Our data confirm the potential utility of KZ in treating ichthyophoniasis and reveal its low toxicity for sea bass. Nevertheless, the optimal dose and appropriate application protocol remain to be determined.

  19. Relative disease susceptibility and clostridial toxin antibody responses in three commercial broiler lines co-infected with Clostridium perfringens and Eimeria maxima using an experimental model of necrotic enteritis

    Science.gov (United States)

    Necrotic enteritis is an enteric disease of poultry resulting from infection by Clostridium perfringens with co-infection by Eimeria spp. constituting a major risk factor for disease pathogenesis. This study compared three commercial broiler chicken lines using an experimental model of necrotic ente...

  20. Time course of gene expression profiling in the liver of experimental mice infected with Echinococcus multilocularis.

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    Renyong Lin

    Full Text Available BACKGROUND: Alveolar echinococcosis (AE is a severe chronic parasitic disease which behaves like a slow-growing liver cancer. Clinical observations suggest that the parasite, Echinococcus multilocularis (E. multilocularis influences liver homeostasis and hepatic cell metabolism. However, this has never been analyzed during the time course of infection in the common model of secondary echinococcosis in experimental mice. METHODOLOGY/PRINCIPAL FINDINGS: Gene expression profiles were assessed using DNA microarray analysis, 1, 2, 3 and 6 months after injection of E. multilocularis metacestode in the liver of susceptible mice. Data were collected at different time points to monitor the dynamic behavior of gene expression. 557 differentially expressed genes were identified at one or more time points, including 351 up-regulated and 228 down-regulated genes. Time-course analysis indicated, at the initial stage of E. multilocularis infection (month 1-2, that most of up-regulated pathways were related to immune processes and cell trafficking such as chemokine-, mitogen-activated protein kinase (MAPK signaling, and down-regulated pathways were related to xenobiotic metabolism; at the middle stage (month 3, MAPK signaling pathway was maintained and peroxisome proliferator-activated receptor (PPAR signaling pathway emerged; at the late stage (month 6, most of up-regulated pathways were related to PPAR signaling pathway, complement and coagulation cascades, while down-regulated pathways were related to metabolism of xenobiotics by cytochrome P450. Quantitative RT-PCR analysis of a random selection of 19 genes confirmed the reliability of the microarray data. Immunohistochemistry analysis showed that proliferating cell nuclear antigen (PCNA was increased in the liver of E. multilocularis infected mice from 2 months to 6 months. CONCLUSIONS: E. multilocularis metacestode definitely exerts a deep influence on liver homeostasis, by modifying a number of gene

  1. Experimental Chagas' disease in dogs

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    Marta de Lana

    1992-03-01

    Full Text Available This paper describes the development of experimental Chagas' disease in 64 out-bred young dogs. Twenty-nine animals were inoculated with the Be-62 and 35 with Be-78 Trypanosoma cruzi strains. Twenty-six were infected with blood trypomastigotes by different inoculation routes and 38 with metacyclic trypomastigotes from the vector via the conjunctival route. Twenty of the 26 dogs infected with blood trypomastigotes were autopsied during the acute phase. Eleven died spontaneously and nine were sacrificed. Six remained alive until they died suddenly (two or were autopsied (four. Twelve of the 38 dogs infected with metacyclic trypomastigotes evolved naturally to the chronic phase and remained alive for 24-48 months. The parasitemia, clinical aspects and serology (IgM and IgG as well as electrocardiogram, hemogram and heart anatomo-histopathologic patterns of acute and chronic cardiac forms of Chagas' disease as seen in human infections, were reproduced. The most important finding is the reproductibility of diffuse fibrosing chronic chagasic cardiopathy in all dogs infected with Be-78 T. cruzi strain autopsied between the 90th and 864th days of infection. Thus, the dog can be considered as a suitable experimental model to study Chagas' disease according to the requisites of the World Health Organization (1984. Futhermore the animal is easily obtained and easy to handle and maintain in experimental laboratory conditions.

  2. Evaluation of {sup 99m}Tc-UBI 29-41 scintigraphy for specific detection of experimental Staphylococcus aureus prosthetic joint infections

    Energy Technology Data Exchange (ETDEWEB)

    Sarda-Mantel, Laure; Meulemans, Alain; Vrigneaud, Jean-Marc; Raguin, Olivier; Lebtahi, Rachida; Guludec, Dominique Le [Universite Denis Diderot-Paris 7, UMR S773, Paris (France); Service de Medecine Nucleaire, AP-HP, Groupe Hospitalier Bichat-Beaujon, Paris (France); INSERM, U773, Paris (France); Saleh-Mghir, Azzam [Universite Versailles-St-Quentin, EA 3647, Garches (France); Welling, Mick M. [Leiden University Medical Center (LUCM), Department of Radiology, Section of Nuclear Medicine, Leiden (Netherlands); Hervatin, Florence [Universite Denis Diderot-Paris 7, UMR S773, Paris (France); CEA, DSV/DRM/SHFJ, Orsay (France); Martet, Genevieve [Universite Denis Diderot-Paris 7, UMR S773, Paris (France); INSERM, U773, Paris (France); Chau, Francoise [Universite Denis Diderot-Paris 7, UMR S773, Paris (France); Universite Denis Diderot Paris 7, EA 3964, Paris (France)

    2007-08-15

    {sup 99m}Tc-UBI 29-41 (UBI), an antimicrobial peptide, specifically targets bacteria. We tested the ability of UBI to discriminate between infected and uninfected prosthetic joints using a rabbit model previously validated. Left knee arthroplasty was performed on 20 New Zealand rabbits, then 10{sup 7} cfu of S. aureus (n = 12) or sterile saline (n = 8) was injected into the joint. On days 9 and 20 after surgery, planar UBI scintigraphy was performed in six infected and four uninfected rabbits, 1 h and 4 h p.i. (150 MBq), on a gamma camera. Operated-to-normal knee activity ratio (ONKR) was calculated on each scintigram. Then, after sacrifice, tissue samples of both knees were counted in a gamma counter. One rabbit injected with sterile saline had cutaneous infection at sacrifice and was excluded from analysis. ONKR was higher in infected than in uninfected animals 4 h p.i. 20 days after surgery: 1.75 {+-} 0.48 vs 1.13 {+-} 0.11, p = 0.04. From 1 h to 4 h p.i., ONKR increased in 9/12 infected and 0/7 uninfected animals. According to UBI uptake intensity and kinetics, scintigraphy was truly positive in all infected cases on day 9 and in four of six infected cases on day 20. It was truly negative in two of three sterile inflamed prosthetic knees on day 9, and in all cases on day 20. Biodistribution studies revealed increased UBI uptake in periprosthetic tissues in all animals 9 days after surgery, and only in infected animals on day 20. In this experimental study, {sup 99m}Tc-UBI 29-41 scintigraphy permitted the early detection of acute prosthetic joint infection, and exclusion of infection in chronic sterile prosthetic joint inflammation. (orig.)

  3. EXPERIMENTAL AND CLINICAL STUDY OF PHENOTYPIC FEATURES OF S. EPIDERMIDIS STRAINS AND THEIR ROLE IN THE EMERGENCE AND DEVELOPMENT OF IMPLANT-ASSOCIATED INFECTION AFTER ORTHOPAEDIC SURGERY

    Directory of Open Access Journals (Sweden)

    S. A. Bozhkova

    2014-01-01

    Full Text Available S. epidermidis is one of the most common cause of implant-associated infections. Infections due to S. epidermidis rarely develops into life-threatening, however, its prevalence and the difficulties in treating constitute a serious financial burden to the health care system. This study is based on the investigation of phenotypic features (ability to biofilm formation and resistance to antibiotics of S. epidermidis strains isolated from patients with deep surgical site infection after implantation of orthopaedic devices, and on the investigation of the dynamics of clinical and morphological changes during the development of implant-associated infection due to S. epidermidis based on in vivo experimental models. Multidrug-resistance was found in 23% MSSE isolates and 97,3% - MRSE. Vancomycin, linezolid and fosfomycin were the most active in relation to these pathogens. About 40% of the tested isolates were strong biofilm-producing strains. 43,2% of MRSE strains and only 21,4% of MSSE isolates demonstrated strong biofilm production. The proposed experimental model shows that intra-operative infection of implant by multidrug-resistant clinical MRSE strain led to the development of osteomyelitis in rats for 4 weeks after surgery, in spite of the revision operation and installation of antimicrobial cement spacer in the area of bone defect. Thus, S. epidermidis is a clinically significant aetiological factor with high risk of development of infections after major orthopaedic surgery.

  4. Purinergic signaling modulates the cerebral inflammatory response in experimentally infected fish with Streptococcus agalactiae: an attempt to improve the immune response.

    Science.gov (United States)

    Souza, Carine F; Baldissera, Matheus D; Bottari, Nathiele B; Moreira, Karen L S; da Rocha, Maria Izabel U M; da Veiga, Marcelo L; Santos, Roberto C V; Baldisserotto, Bernardo

    2018-06-01

    Appropriate control of the immune response is a critical determinant of fish health, and the purinergic cascade has an important role in the immune and inflammatory responses. This cascade regulates the levels of adenosine triphosphate (ATP), adenosine diphosphate, adenosine monophosphate and adenosine (Ado), molecules involved in physiological or pathological events as inflammatory and anti-inflammatory mediators. Thus, the aim of this study was to evaluate whether purinergic signaling, through the activities of nucleoside triphosphate diphosphohydrolase (NTPDase), 5'-nucleotidase, and adenosine deaminase (ADA), is capable of modulating the cerebral immune and inflammatory responses in silver catfish that is experimentally infected with Streptococcus agalactiae. Cerebral NTPDase (with ATP as substrate) and 5'-nucleotidase activities increased, while ADA activity decreased in silver catfish that is experimentally infected with S. agalactiae, compared to the control group. Moreover, the cerebral levels of ATP and Ado increased in infected animals compared to the uninfected control group. Brain histopathology in infected animals revealed inflammatory demyelination (the presence of occasional bubbly collections), increased cellular density in the area near to pia-mater and intercellular edema. Based on this evidence, the modulation of the purinergic cascade by the enzymes NTPDase, 5'-nucleotidase, and ADA exerts an anti-inflammatory profile due to the regulation of ATP and Ado levels. This suggests involvement of purinergic enzymes on streptococcosis pathogenesis, through regulating cerebral ATP and Ado levels, molecules known to participate in physiological or pathological events as inflammatory and anti-inflammatory mediators, respectively. In summary, the modulation of the cerebral purinergic cascade exerts an anti-inflammatory profile in an attempt to reduce inflammatory damage.

  5. Effectiveness of netilmicin and tobramycin against Pseudomonas aeruginosa in vitro and in an experimental tissue infection in mice.

    Science.gov (United States)

    Moffie, B G; Hoogeterp, J J; Lim, T; Douwes-Idema, A E; Mattie, H

    1993-03-01

    The activity of netilmicin and tobramycin against Pseudomonas aeruginosa was assessed in vitro in the presence of constant and exponentially declining concentrations, and in mice in an experimental thigh infection. The activity in vitro at constant concentrations was expressed as the maximal killing rate (ER) during 3 h of exposure. On the basis of the quantitative relation between E(R) and the drug concentration, the numbers of cfu expected at consecutive times, at constant as well as at declining concentrations, were predicted. The relationship between observed numbers and predicted values of ERt were similar under both conditions for both drugs. On the same basis the numbers of cfu expected in the experimental thigh infection were predicted. There was indeed a significant linear relationship between observed numbers of cfu in homogenized muscle and the values predicted on the basis of the pharmacokinetics of the aminoglycosides, but the slope of this relationship was only 0.22. There was no difference in this respect between the two antibiotics. It is concluded that the efficacy of netilmicin and tobramycin against P. aeruginosa is considerably less in vivo than in vitro, but the relation is about the same for the two drugs; therefore the slightly higher activity of tobramycin in vitro is relevant in the in-vivo situation.

  6. Acute phase response in two consecutive experimentally induced E. coli intramammary infections in dairy cows

    Directory of Open Access Journals (Sweden)

    Saatsi Johanna

    2008-06-01

    Full Text Available Abstract Background Acute phase proteins haptoglobin (Hp, serum amyloid A (SAA and lipopolysaccharide binding protein (LBP have suggested to be suitable inflammatory markers for bovine mastitis. The aim of the study was to investigate acute phase markers along with clinical parameters in two consecutive intramammary challenges with Escherichia coli and to evaluate the possible carry-over effect when same animals are used in an experimental model. Methods Mastitis was induced with a dose of 1500 cfu of E. coli in one quarter of six cows and inoculation repeated in another quarter after an interval of 14 days. Concentrations of acute phase proteins haptoglobin (Hp, serum amyloid A (SAA and lipopolysaccharide binding protein (LBP were determined in serum and milk. Results In both challenges all cows became infected and developed clinical mastitis within 12 hours of inoculation. Clinical disease and acute phase response was generally milder in the second challenge. Concentrations of SAA in milk started to increase 12 hours after inoculation and peaked at 60 hours after the first challenge and at 44 hours after the second challenge. Concentrations of SAA in serum increased more slowly and peaked at the same times as in milk; concentrations in serum were about one third of those in milk. Hp started to increase in milk similarly and peaked at 36–44 hours. In serum, the concentration of Hp peaked at 60–68 hours and was twice as high as in milk. LBP concentrations in milk and serum started to increase after 12 hours and peaked at 36 hours, being higher in milk. The concentrations of acute phase proteins in serum and milk in the E. coli infection model were much higher than those recorded in experiments using Gram-positive pathogens, indicating the severe inflammation induced by E. coli. Conclusion Acute phase proteins would be useful parameters as mastitis indicators and to assess the severity of mastitis. If repeated experimental intramammary

  7. The challenge of using experimental infectivity data in risk assessment for Ebola virus: why ecology may be important.

    Science.gov (United States)

    Gale, P; Simons, R R L; Horigan, V; Snary, E L; Fooks, A R; Drew, T W

    2016-01-01

    Analysis of published data shows that experimental passaging of Zaire ebolavirus (EBOV) in guinea pigs changes the risk of infection per plaque-forming unit (PFU), increasing infectivity to some species while decreasing infectivity to others. Thus, a PFU of monkey-adapted EBOV is 10(7) -fold more lethal to mice than a PFU adapted to guinea pigs. The first conclusion is that the infectivity of EBOV to humans may depend on the identity of the donor species itself and, on the basis of limited epidemiological data, the question is raised as to whether bat-adapted EBOV is less infectious to humans than nonhuman primate (NHP)-adapted EBOV. Wildlife species such as bats, duikers and NHPs are naturally infected by EBOV through different species giving rise to EBOV with different wildlife species-passage histories (heritages). Based on the ecology of these wildlife species, three broad 'types' of EBOV-infected bushmeat are postulated reflecting differences in the number of passages within a given species, and hence the degree of adaptation of the EBOV present. The second conclusion is that the prior species-transmission chain may affect the infectivity to humans per PFU for EBOV from individuals of the same species. This is supported by the finding that the related Marburg marburgvirus requires ten passages in mice to fully adapt. It is even possible that the evolutionary trajectory of EBOV could vary in individuals of the same species giving rise to variants which are more or less virulent to humans and that the probability of a given trajectory is related to the heritage. Overall the ecology of the donor species (e.g. dog or bushmeat species) at the level of the individual animal itself may determine the risk of infection per PFU to humans reflecting the heritage of the virus and may contribute to the sporadic nature of EBOV outbreaks. © 2015 Crown copyright. © 2015 Society for Applied Microbiology.

  8. Experimental infection of ponies with Sarcocystis fayeri and differentiation from Sarcocystis neurona infections in horses.

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    Saville, W J A; Dubey, J P; Oglesbee, M J; Sofaly, C D; Marsh, A E; Elitsur, E; Vianna, M C; Lindsay, D S; Reed, S M

    2004-12-01

    Sarcocystis neurona and Sarcocystis fayeri infections are common in horses in the Americas. Their antemortem diagnosis is important because the former causes a neurological disorder in horses, whereas the latter is considered nonpathogenic. There is a concern that equine antibodies to S. fayeri might react with S. neurona antigens in diagnostic tests. In this study, 4 ponies without demonstrable serum antibodies to S. neurona by Western immunoblot were used. Three ponies were fed 1 x 10(5) to 1 x 10(7) sporocysts of S. fayeri obtained from dogs that were fed naturally infected horse muscles. All ponies remained asymptomatic until the termination of the experiment, day 79 postinoculation (PI). All serum samples collected were negative for antibodies to S. neurona using the Western blot at the initial screening, just before inoculation with S. fayeri (day 2) and weekly until day 79 PI. Cerebrospinal fluid samples from each pony were negative for S. neurona antibodies. Using the S. neurona agglutination test, antibodies to S. neurona were not detected in 1:25 dilution of sera from any samples, except that from pony no. 4 on day 28; this pony had received 1 X 10(7) sporocysts. Using indirect immunofluorescence antibody tests (IFATs), 7 serum samples were found to be positive for S. neurona antibodies from 1:25 to 1:400 dilutions. Sarcocystis fayeri sarcocysts were found in striated muscles of all inoculated ponies, with heaviest infections in the tongue. All sarcocysts examined histologically appeared to contain only microcytes. Ultrastructurally, S. fayeri sarcocysts could be differentiated from S. neurona sarcocysts by the microtubules (mt) in villar protrusions on sarcocyst walls; in S. fayeri the mt extended from the villar tips to the pellicle of zoites, whereas in S. neurona the mt were restricted to the middle of the cyst wall. Results indicate that horses with S. fayeri infections may be misdiagnosed as being S. neurona infected using IFAT, and further research

  9. Lassa virus infection in experimentally infected marmosets: liver pathology and immunophenotypic alterations in target tissues.

    Science.gov (United States)

    Carrion, Ricardo; Brasky, Kathleen; Mansfield, Keith; Johnson, Curtis; Gonzales, Monica; Ticer, Anysha; Lukashevich, Igor; Tardif, Suzette; Patterson, Jean

    2007-06-01

    Lassa virus causes thousands of deaths annually in western Africa and is considered a potential biological weapon. In an attempt to develop a small nonhuman primate model of Lassa fever, common marmosets were subcutaneously inoculated with Lassa virus strain Josiah. This inoculation resulted in a systemic disease with clinical and morphological features mirroring those in fatal human Lassa infection: fever, weight loss, high viremia and viral RNA load in tissues, elevated liver enzymes, and severe morbidity between days 15 and 20. The most prominent histopathology findings included multifocal hepatic necrosis with mild inflammation and hepatocyte proliferation, lymphoid depletion, and interstitial nephritis. Cellular aggregates in regions of hepatocellular necrosis were largely composed of HAM56-positive macrophages, devoid of CD3-positive and CD20-positive cells, and characterized by marked reductions in the intensity of HLA-DP, DQ, DR staining. A marked reduction in the major histocompatibility complex class II expression was also observed in the lymph nodes. Immunophenotypic alterations in spleen included reductions in overall numbers of CD20-positive and CD3-positive cells and the disruption of lymphoid follicular architecture. These findings identify the common marmoset as an appropriate model of human Lassa fever and present the first experimental evidence that replication of Lassa virus in tissues is associated with alterations that would be expected to impair adaptive immunity.

  10. Effects of experimental Trypanosoma evansi infection on pregnancy in Yankasa ewes.

    Science.gov (United States)

    Adeyeye, A A; Ate, I U; Lawal, A I; Adamu, S

    2016-03-15

    Twenty pregnant Yankasa ewes were assigned to three groups to determine the effect of Trypanosoma evansi infection on pregnancy. Groups A and B comprising seven ewes each were infected with approximately 1.0 × 10(6) cells of T evansi per ewe through venepuncture at the second and third trimesters of pregnancy, respectively. Group C comprising six ewes served as uninfected control. There was slight pyrexia in the infected groups (groups A and B) but was absent in group C. The mean body weight, glucose concentration, and packed cell volume of ewes in group A were not significantly different from those in group C throughout the study. There was also no significant difference in mean glucose concentration between groups B and C. However, in group B, mean body weight was significantly (P ewes in group A was significantly (P ewes in group B decreased significantly (P ewes in the infected groups (groups A and B) compared with those in group C. However, there were significant (P ewes in group B compared with ewes in groups A and C. Mice inoculation with blood from infected ewes postpartum was parasitemic 18 to 25 days pi, for ewes in group B, whereas none of the mice in groups A and C were parasitemic. Lambs born from the infected groups (groups A and B) were also aparasitemic for 40 days postpartum. It was therefore concluded that the T evansi isolate used caused mild trypanosomosis when infected at third trimester, whereas ewes infected at second trimester were resistant. Copyright © 2016 Elsevier Inc. All rights reserved.

  11. Aspects of Toxoplasma Infection on the Reproductive System of Experimentally Infected Rams (Ovis Aries

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    Welber Daniel Zanetti Lopes

    2009-01-01

    Full Text Available Eight reproductive rams with no prior reproductive disease were distributed into three groups of infection with T. gondii: GI, 3 rams, 2.0×105 P strain oocysts; GII, 3 rams, 1.0×106 RH strain tachyzoites; GIII, 2 control rams. Clinical parameters were measured and serological evaluations (IIF were performed. Presence of the parasite in the semen was investigated by PCR and bioassay techniques. The rams presented clinical alterations (hyperthermia and apathy related to toxoplasmosis in both groups infected with Toxoplasma gondii. All the inoculated rams responded to antigenic stimulus, producing antibodies against T. gondii from postinoculation day 5 onwards. In ovine groups I and II, the greatest titers observed were 1 : 4096 and 1 : 8192, respectively. In semen samples collected from these two groups, the presence of T. gondii was detected by bioassay and PCR. This coccidian was isolated (bioassay and PCR in tissue pools (testicles, epididymis, seminal vesicle, and prostrate from two rams infected presenting oocysts and in one presenting tachyzoites.

  12. Clinical and Histopathological Evaluation of Terbinafine Treatment in Cats Experimentally Infected with Microsporum canis

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    T. Kotnik

    2006-01-01

    Full Text Available The efficacy of terbinafine hydrochloride (Lamisil©, Novartis in the treatment of 27 M. canis infected cats was followed. Treatment was started on the 17th day post inoculation (p.i., when successful experimental infection was proved. Nine cats were treated with low-dose terbinafine 10-20 mg/kg QD (LD group, nine cats were treated with high-dose terbinafine 30-40 mg/kg QD (HD group and nine were left untreated as a control group (C group. The efficacy of the treatment was evaluated using Wood's lamp examination, fungal culture and histopathology. All cats were positive 14 days p.i. Sixty days p.i. 8 cats from the LD group, 9 from the C group and 2 cats from the HD group had fungi in the tissue. Ninety days p.i. the HD group was free of fungi in the skin and other tests became negative on the 120th day p.i. Statistically significant differences were found between the HD group and both of the other groups (p M. canis yielded an inflammatory reaction of a mononuclear and neutrophil type in the cat skin. Hyperplastic interstitial dermatitis was a predominant tissue reaction although other types were also present during the study.

  13. Human rhinovirus in experimental infection after peroral Lactobacillus rhamnosus GG consumption, a pilot study.

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    Tapiovaara, Laura; Kumpu, Minna; Mäkivuokko, Harri; Waris, Matti; Korpela, Riitta; Pitkäranta, Anne; Winther, Birgit

    2016-08-01

    Data has emerged on possible beneficial effects of probiotics in respiratory tract viral infections, but it is unclear if the promising positive effects evidenced are due to a reduced viral load during infections. The aims of this work were to investigate the effect of peroral probiotic Lactobacillus rhamnosus GG (American Type Culture Collection [ATCC], Accession No. 53103) consumption on human rhinovirus (HRV) load in nasopharyngeal lavage samples in experimental HRV infection, and to correlate viral load to clinical symptoms. Intranasal HRV A39 inoculation was performed on 59 adults, who had consumed juice enriched with live or heat-inactivated L. rhamnosus GG or control juice for 3 weeks prior to inoculation in a randomized, controlled, pilot trial setting. Nasopharyngeal lavage samples and symptom data were analyzed on day 0 before inoculation, and on days 2 and 5. Samples were subjected to quantitative HRV detection by polymerase chain reaction (PCR). Before inoculation 9 of 59 (15%) samples presented with another HRV strain than the studied A39. There was a tendency toward the lowest HRV loads in the L. rhamnosus GG groups and the highest in placebo group (log10 copies/mL, 95% confidence interval [CI], 6.20 [5.18 to 7.40] in live, 6.30 [4.91 to 7.08] in inactivated L. rhamnosus GG, and 7.25 [5.81 to 7.52] in placebo group, p = 0.57 in day 2) in the wild-type excluded population. The HRV load positively correlated with the symptom scores on days 2 and 5 (correlation coefficient 0.61 [p rhamnosus GG when compared to placebo. HRV load positively correlated with the total symptom scores. © 2016 ARS-AAOA, LLC.

  14. Avian metapneumovirus subtype B experimental infection and tissue distribution in chickens, sparrows, and pigeons.

    Science.gov (United States)

    Gharaibeh, S; Shamoun, M

    2012-07-01

    Avian metapneumovirus (aMPV) is a respiratory virus that infects a range of avian hosts, including chickens and turkeys. Migratory and local wild birds are implicated in aMPV spread among farms, countries, and seasonal outbreaks of the disease. A subtype B aMPV isolate from commercial chicken flocks suffering from respiratory disease was experimentally inoculated oculonasally into 7-week old chickens, young pigeons, and sparrows. Chickens showed minimal tracheal rales, whereas pigeons and sparrows were asymptomatic. Shedding of aMPV was detected by reverse transcription polymerase chain reaction on homogenates from nasal turbinates. At 5 days postinfection, 5 of 5 chickens, 2 of 5 pigeons, and 1 of 5 sparrows were positive; at 10 or 15 days, none were positive. At 2 and 5 days, aMPV antigens were localized at the ciliated boarder of respiratory epithelium in nasal cavity and trachea of chickens, as well as to the conjunctival epithelium. Pigeons had detectable viral antigens in only the trachea at 2 and 5 days; sparrow tissues did not show any positive staining. At the end of the experiment, at 21 days postinfection, 14 of 15 inoculated chickens seroconverted against aMPV, but none of the inoculated pigeons or sparrows did. The authors believe that pigeons and sparrows have the ability to transmit the virus between chicken farms, although they do not consider pigeons and sparrows as natural hosts for aMPV, given that they failed to seroconvert. In conclusion, pigeons and sparrows are partially susceptible to aMPV infection, probably acting more as mechanical vectors because infection is only temporary and short-lived.

  15. Preclinical deposition of pathological prion protein in muscle of experimentally infected primates.

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    Susanne Krasemann

    Full Text Available Prion diseases are transmissible fatal neurodegenerative disorders affecting humans and animals. A central step in disease progression is the accumulation of a misfolded form (PrP(Sc of the host encoded prion protein (PrP(C in neuronal and non-neuronal tissues. The involvement of peripheral tissues in preclinical states increases the risk of accidental transmission. On the other hand, detection of PrP(Sc in non-neuronal easy-accessible compartments such as muscle may offer a novel diagnostic tool. Primate models have proven invaluable to investigate prion diseases. We have studied the deposition of PrP(Sc in muscle and central nervous system of rhesus monkeys challenged with sporadic Creutzfeldt-Jakob disease (sCJD, variant CJD (vCJD and bovine spongiform encephalopathy (BSE in preclinical and clinical stage using biochemical and morphological methods. Here, we show the preclinical presence of PrP(Sc in muscle and central nervous system of rhesus monkeys experimentally infected with vCJD.

  16. EXPERIMENTAL CHALLENGE STUDY OF FV3-LIKE RANAVIRUS INFECTION IN PREVIOUSLY FV3-LIKE RANAVIRUS INFECTED EASTERN BOX TURTLES (TERRAPENE CAROLINA CAROLINA) TO ASSESS INFECTION AND SURVIVAL.

    Science.gov (United States)

    Hausmann, Jennifer C; Wack, Allison N; Allender, Matthew C; Cranfield, Mike R; Murphy, Kevin J; Barrett, Kevin; Romero, Jennell L; Wellehan, James F X; Blum, Stella A; Zink, M Christine; Bronson, Ellen

    2015-12-01

    The Maryland Zoo in Baltimore experienced an outbreak of Frog virus-3 (FV3)-like ranavirus during the summer of 2011, during which 14 of 27 (52%) of its captive eastern box turtles (Terrapene carolina carolina) survived. To assess survival, immunity, and viral shedding, an experimental challenge study was performed in which the surviving, previously infected turtles were reinfected with the outbreak strain of FV3-like ranavirus. Seven turtles were inoculated with virus intramuscularly and four control turtles received saline intramuscularly. The turtles were monitored for 8 wk with blood and oral swabs collected for quantitative polymerase chain reaction (qPCR). During that time, one of seven (14%) inoculated turtles and none of the controls (0%) died; there was no significant difference in survival. Clinical signs of the inoculated turtles, except for the turtle that died, were mild compared to the original outbreak. Quantitative PCR for FV3-like ranavirus on blood and oral swabs was positive for all inoculated turtles and negative for all controls. The turtle that died had intracytoplasmic inclusion bodies in multiple organs. Three inoculated and two control turtles were euthanized at the end of the study. No inclusion bodies were present in any of the organs. Quantitative PCR detected FV3-like ranavirus in the spleen of a control turtle, which suggested persistence of the virus. The surviving five turtles were qPCR-negative for FV3-like ranavirus from blood and oral swabs after brumation. Quantitative PCR for Terrapene herpesvirus 1 found no association between ranavirus infection and herpesvirus loads. In conclusion, previously infected eastern box turtles can be reinfected with the same strain of FV3-like ranavirus and show mild to no clinical signs but can shed the virus from the oral cavity.

  17. Transcriptional Profiling Identifies Location-Specific and Breed-Specific Differentially Expressed Genes in Embryonic Myogenesis in Anas Platyrhynchos.

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    Rong-Ping Zhang

    Full Text Available Skeletal muscle growth and development are highly orchestrated processes involving significant changes in gene expressions. Differences in the location-specific and breed-specific genes and pathways involved have important implications for meat productions and meat quality. Here, RNA-Seq was performed to identify differences in the muscle deposition between two muscle locations and two duck breeds for functional genomics studies. To achieve those goals, skeletal muscle samples were collected from the leg muscle (LM and the pectoral muscle (PM of two genetically different duck breeds, Heiwu duck (H and Peking duck (P, at embryonic 15 days. Functional genomics studies were performed in two experiments: Experiment 1 directly compared the location-specific genes between PM and LM, and Experiment 2 compared the two breeds (H and P at the same developmental stage (embryonic 15 days. Almost 13 million clean reads were generated using Illumina technology (Novogene, Beijing, China on each library, and more than 70% of the reads mapped to the Peking duck (Anas platyrhynchos genome. A total of 168 genes were differentially expressed between the two locations analyzed in Experiment 1, whereas only 8 genes were differentially expressed when comparing the same location between two breeds in Experiment 2. Gene Ontology (GO and the Kyoto Encyclopedia of Genes and Genomes pathways (KEGG were used to functionally annotate DEGs (differentially expression genes. The DEGs identified in Experiment 1 were mainly involved in focal adhesion, the PI3K-Akt signaling pathway and ECM-receptor interaction pathways (corrected P-value<0.05. In Experiment 2, the DEGs were associated with only the ribosome signaling pathway (corrected P-value<0.05. In addition, quantitative real-time PCR was used to confirm 15 of the differentially expressed genes originally detected by RNA-Seq. A comparative transcript analysis of the leg and pectoral muscles of two duck breeds not only

  18. Experimental infection of the bat tick Carios fonsecai (Acari: Ixodidae with the rabies virus

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    Silvana Regina Favoretto

    2013-12-01

    Full Text Available Introduction This study assessed the viability of the rabies virus in the argasid tick Carios fonsecai following experimental infection. Methods The mouse inoculation test (MIT, fluorescent antibody test (FAT and polymerase chain reaction (PCR were used. The rabies virus was administered to ticks via the intra-coelomic route, and the ticks were sacrificed at different time points. Results The inoculated ticks were negative for rabies according to the MIT. Ticks macerated with rabies virus were positive according to the MIT and FAT. All of the tick lots tested by PCR were positive. Conclusions The rabies virus became unviable shortly after its inoculation into tick bodies. Ticks are not likely to play an important role in the epidemiology of rabies.

  19. An ultrasonic study of experimental infected hydronephrosis in rabbit

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    Choi, Byung Ihn; Yu, Yun Jeong; Han, Man Chung; Kim, Chu Wan

    1983-01-01

    Ultrasonography of rabbit kidney was performed after induction of infected hydronephrosis to evaluate the sequential sonographic changes in 15 rabbits. Infected hydronephrosis was induced by ligation of the distal ureter and ureteral inoculation of Escherichia coli. Ultrasonography was performed daily during the first two weeks and weekly during the following 4 weeks after induction of infected hydronephrosis. The results are as follows: 1. The earliest abnormal ultrasonographic findings was appearance of internal echoes in dependent portion of the pelvis, which appeared within 4 days after inoculation in all cases. 2. Degree of internal echoes within the pelvis increased progressively with lapse of time and the entire pelvis was filled with internal echoes within 2 weeks after inoculation in all cases. 3. Echogenecity of internal echoes within the pelvis was similar to that of renal parenchyma in the first week after inoculation, however was weaker than that of renal parenchyma 2 weeks after inoculation in all cases

  20. Infecção experimental em cabritos pelo vírus da artrite encefalite Caprine arthritis encephalitis virus experimental infection in new-born kids

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    M.I.M.C. Guedes

    2001-02-01

    Full Text Available Vinte e quatro caprinos de uma semana de idade, soronegativos pela imunodifusão em gel de agar para artrite encefalite caprina (AEC, foram utilizados para estudo de infecção experimental pelo vírus da AEC. Dezesseis animais foram inoculados com lentivirus caprino, amostra Cork, oito pela via intravenosa e oito por instilação nasal. Oito animais serviram como controle, inoculados pelas vias intranasal ou intravenosa com 1ml de meio de cultura de células não infectadas. Os animais foram sacrificados aos 2, 6, 12 e 20 dias pós-inoculação (PI, e colhidas amostras do sistema nervoso central, articulações, tonsilas, linfonodos, pulmões, rins, timo, baço e intestinos delgado e grosso para histopatologia e imunoistoquímica. Um animal inoculado com o vírus da AEC pela via intranasal e sacrificado aos 20 dias PI apresentou imunomarcação positiva em um macrófago alveolar. Concluiu-se que a via aerógena é uma provável rota de infecção pelo vírus da AEC.The caprine arthritis encephalitis virus (CAEV experimental infection was studied in 24 one-week-old seronegative kids. Sixteen kids were inoculated with CAEV-Cork, with 10(6 TCID50/ml concentration, being eight inoculated intravenously, and eight intranasally. Eight animals were used as controls, being four inoculated intravenously, and four intranasally with non-infected cell culture medium. Since the day of the inoculation, clinical evaluation was performed daily, until the day of the sacrifice. Blood samples were taken for serological tests. The animals were killed in pairs at 2, 6, 12 and 20 days post-inoculation (PI and tissues samples of central nervous system, joints, tonsils, lymphonodes, lungs, kidneys, thymus, spleen, small and large intestine were collected for histopathological and immunohistochemical studies. One animal CAEV inoculated intranasally and killed at 20 days PI showed immunohistochemical positive reaction in an alveolar macrophage. It was concluded that

  1. High concentration of human lactoferrin in milk of rhLf-transgenic cows relieves signs of bovine experimental Staphylococcus chromogenes intramammary infection.

    Science.gov (United States)

    Simojoki, Heli; Hyvönen, Paula; Orro, Toomas; Pyörälä, Satu

    2010-08-15

    Six transgenic cows producing recombinant human lactoferrin (rhLf) in their milk and five normal cows at the same lactation stage were experimentally infected with Staphylococcus chromogenes to study the effect of a high concentration of lactoferrin in milk. Coagulase-negative staphylococci such as S. chromogenes have become very common as agents causing mild or subclinical mastitis. All transgenic cows became infected but showed no clinical signs, unlike the control cows, which developed mild clinical mastitis. Transgenic cows eliminated bacteria faster from the quarters than did the controls. Local clinical signs were milder, and the inflammatory reaction assessed by NAGase activity in the milk and by the concentration of milk amyloid A was lower in the transgenic cows. The mild response probably reflected the rapid elimination of bacteria. The milk concentration of rhLf remained constant throughout the study period, but the total concentration of bovine lactoferrin in the milk peaked in both groups at 46h post-challenge. Three cows, all in the control group, exhibited systemic acute phase response as increased concentrations of serum amyloid A in the blood circulation. Transgenic cows with a high concentration of human lactoferrin in their milk seemed to be protected from clinical disease and from prolonged inflammatory reaction, but not from experimental intramammary infection induced by S. chromogenes. Copyright 2010 Elsevier B.V. All rights reserved.

  2. Involvement of cholinergic and adenosinergic systems on the branchial immune response of experimentally infected silver catfish with Streptococcus agalactiae.

    Science.gov (United States)

    Baldissera, M D; Souza, C F; Doleski, P H; Moreira, K L S; da Veiga, M L; da Rocha, M I U M; Santos, R C V; Baldisserotto, B

    2018-01-01

    It has been recognized that the cholinergic and adenosinergic systems have an essential role in immune and inflammatory responses during bacterial fish pathogens, such as the enzymes acetylcholinesterase (AChE) and adenosine deaminase (ADA), which are responsible for catalysis of the anti-inflammatory molecules acetylcholine (ACh) and adenosine (Ado) respectively. Thus, the aim of this study was to investigate the involvement of the cholinergic and adenosinergic systems on the immune response and inflammatory process in gills of experimentally infected Rhamdia quelen with Streptococcus agalactiae. Acetylcholinesterase activity decreased, while ACh levels increased in gills of infected animals compared to uninfected animals. On the other hand, a significant increase in ADA activity with a concomitant decrease in Ado levels was observed in infected animals compared to uninfected animals. Based on this evidence, we concluded that infection by S. agalactiae in silver catfish alters the cholinergic and adenosinergic systems, suggesting the involvement of AChE and ADA activities on immune and inflammatory responses, regulating the ACh and Ado levels. In summary, the downregulation of AChE activity exerts an anti-inflammatory profile in an attempt to reduce or prevent the tissue damage, while the upregulation of ADA activity exerts a pro-inflammatory profile, contributing to disease pathophysiology. © 2017 John Wiley & Sons Ltd.

  3. The potential of methylethylpiridinol in treatment of bacterial infections caused by Klebsiella pneumoniae (experimental study

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    V. M. Brykhanov

    2016-01-01

    Full Text Available Aim. Investigated the activity of methylethylpiridinol (6-methyl-2-ethyl-pyridin-3-ol hydrochloride in the comprehensive treatment of the experimental bacterial infection caused by Klebsiella pneumoniae.Materials and methods. The study was conducted on clinical isolates of Klebsiella pneumoniae. At the first stage of the study (in vitro studied the effect of methylethylpiridinol in concentrations 0,25–4 mM on the growth of the strain and the activity of the sublethal concentrations of antibiotics – gentamicin, ciprofloxacin, tetracycline, ceftazidime. In the second stage of the study (in vivo in rats Wistar simulated bacterial peritonitis by intraperitoneal injection of a suspension of Klebsiella pneumoniae and investigated the effect of methylethylpiridinol (80 mg/kg on the effectiveness of antibiotic therapy with gentamicin (30 mg/kg, ciprofloxacin (50 mg/kg, ceftazidime (120 mg/kg or tetracycline (80 mg/kg. The animal blood plasma was determined ceruloplasmin concentration (marker of the intensity of infectious-inflammatory process and thiobarbiturate-jet products, erythrocytes – the concentration of reduced glutathione, catalase and glutathione peroxidase.Results. It is found that a methylethylpiridinol inhibits the development of periodic bacterial cultures, but exhibits a pronounced antagonism with respect to gentamicin. Antioxidant slightly increases the activity of ciprofloxacin and tetracycline. The bacteriostatic effect of antioxidant reduces the action of ceftazidime in vitro. In conditions of chemotherapy by using of gentamicin and ciprofloxacin additional injection of methylethylpiridinol leads to the preservation of ceruloplasmin level to the level of non-treated animals without showing the antioxidant effect. Ceftazidime exhibits antioxidant effect, reduces the introduction of methylethylpiridinol. The antioxidant properties of methylethylpiridinol did not appear in the application of

  4. Histopathology of red-sore disease (aeromonas hydrophila) in naturally and experimentally infected largemouth bass micropterus salmoides(lacepede)

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    Huizinga, H W [Illinois State Univ., Normal; Esch, G W; Hazen, T C

    1979-01-01

    The histopathology of red-sore disease, caused by the gram-negative bacterium, Aeromonas hydrophila, is described for largemouth bass, Micropterus salmoides. Externally, lesions range from those affecting a few scales (pin-point), to those associated with extensive chronic ulcerations; there is focal hemorrhage, oedema and dermal necrosis which exposes underlying muscles producing infiltration of mononuclear and granulocytic inflammatory cells. Internally, the liver and kidneys are foci for toxic products produced by A. hydrophila with, in the most severe cases, complete destruction of the structural integrity of both organs. Pathological changes were not serious in either the spleen or heart, even in cases with massive damage in the liver and kidney. Internal and external lesions were similar in both natural and experimentally induced infections. The pathobiology of red-sore disease in bass was postulated to be linked to elevated water temperature stimulating increased metabolism, decreased body condition and stress, leading to the increased production of corticosteroids and the concommitant rise in susceptibility to infection.

  5. Angiostrongylus costaricensis and experimental infection of Sarasinula marginata II: elimination routes

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    Mendonça Cristiane Lafeta Gomes Furtado

    2003-01-01

    Full Text Available Angiostrongylus costaricensis intermediate hosts are terrestrial mollusks mostly belonging to the Veronicellidae family. In the present investigation we focused on the mechanisms of larval expulsion from Sarasinula marginata infected with A. costaricensis. Twenty-five mollusks were individually infected with 5000 L1 and sacrificed at 30 min and 1, 2, 4, 6, and 8 h post-infection and at days 1, 2, 4, 5, 6, 8, 10, 11, 12, 14, 15, 16, 20, 21, 22, 25, 26, 28, and 30 post-infection; the mollusks were then fixed and stained. Diverse organs involved throughout the course of the migratory routes of larvae from oral penetration on were specified and the mechanisms of larval access to the fibromuscular layer through the kidney, rectum, and vascular system were defined. The elimination of L3, derived from oral and/or cutaneous infections, appears to depend on granulomas located close to the excretory ducts of mucous cells.

  6. Different infective forms trigger distinct immune response in experimental Chagas disease.

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    Paula Melo de Abreu Vieira

    Full Text Available Although metacyclic and blood trypomastigotes are completely functional in relation to parasite-host interaction and/or target cell invasion, they differ in the molecules present on the surface. Thus, aspects related to the variability that the forms of T. cruzi interacts with host cells may lead to fundamental implications on the immune response against this parasite and, consequently, the clinical evolution of Chagas disease. We have shown that BT infected mice presented higher levels of parasitemia during all the acute phase of infection. Moreover, the infection with either MT or BT forms resulted in increased levels of total leukocytes, monocytes and lymphocytes, specifically later for MT and earlier for BT. The infection with BT forms presented earlier production of proinflammatory cytokine TNF-α and later of IFN-γ by both T cells subpopulations. This event was accompanied by an early cardiac inflammation with an exacerbation of this process at the end of the acute phase. On the other hand, infection with MT forms result in an early production of IFN-γ, with subsequent control in the production of this cytokine by IL-10, which provided to these animals an immunomodulatory profile in the end of the acute phase. These results are in agreement with what was found for cardiac inflammation where animals infected with MT forms showed intense cardiac inflammation later at infection, with a decrease in the same at the end of this phase. In summary, our findings emphasize the importance of taking into account the inoculums source of T. cruzi, since vectorial or transfusional routes of T. cruzi infection may trigger distinct parasite-host interactions during the acute phase that may influence relevant biological aspects of chronic Chagas disease.

  7. E-NTPDase and E-ADA activities in lymphocytes associated with the immune response of rats experimentally infected with Toxoplasma gondii.

    Science.gov (United States)

    Tonin, Alexandre A; Da Silva, Aleksandro S; Ruchel, Jader B; Rezer, João F P; Camillo, Giovana; Faccio, Luciana; França, Raqueli T; Leal, Daniela B R; Duarte, Marta M M F; Vogel, Fernada F; de la Rue, Mario L; Lopes, Sonia T A

    2013-10-01

    An investigation of E-NTPDase and E-ADA activities in lymphocytes from rats experimentally infected with Toxoplasma gondii was carried out in this study. For this purpose, twenty four adult male Wistar rats were divided in two groups/four subgroups (A1 and A2; B1 and B2-6 animal/each group), with "A" as uninfected and "B" inoculated with T. gondii (RH strain). Sampling was performed on days 5 and 10 post-infection (p.i.), with evaluation of hemogram, immunoglobulins (IgM and IgG) and activity of E-NTPDase and E-ADA in lymphocytes. Enzymes essays showed ATP hydrolysis increased on days 5 (PADA activity on lymphocytes was also increased in both evaluated periods (PADA increased activities observed on lymphocytes, it is possible to suggest their involvement in an anti-inflammatory response, consisting of a modulatory response, preventing excessive tissue damage caused by the infection with Toxoplasma gondii. Copyright © 2013 Elsevier Inc. All rights reserved.

  8. Dexamethasone treatment induces susceptibility of outbred Webster mice to experimental infection with Besnoitia darlingi isolated from opossums (Didelphis virginiana).

    Science.gov (United States)

    Elsheikha, Hany M; Rosenthal, Benjamin M; Mansfield, Linda S

    2005-04-01

    The Sarcocystidae comprise a diverse, monophyletic apicomplexan parasite family, most of whose members form intracellular cysts in their intermediate hosts. The extent of pathology associated with such cyst formation can range widely. We currently lack experimental animal models for many of these infections. Here we explored dexamethasone treatment as a means to render outbred mice susceptible to Besnoitia darlingi infection and demonstrated that this approach allows viable parasites to be subsequently isolated from these mice and maintained in tissue culture. Besnoitia bradyzoites recovered from crushed cysts derived from naturally infected opossums (Didelphis virginiana) replicated and reproduced the development of besnoitiosis in mice treated with dexamethasone (0.5 mg/ml drinking water) daily for 12 days post infection (DPI). Isolates recovered from the peritoneal exudates of these mice were viable and were maintained in long-term tissue cultures. In contrast, control mice given saline without dexamethasone and challenged with similar bradyzoites remained clinically normal for up to 70 DPI. An additional group of mice challenged with the same inoculum of bradyzoites and given dexamethasone at the same concentration and treated with sulfadiazine (1 mg/ml drinking water) daily for 12 DPI also remained normal for up to 70 DPI. Severe disease developed more rapidly in dexamethasone-treated mice inoculated with culture-derived B. darlingi tachyzoites than in those inoculated with cyst-derived bradyzoites. B. darlingi tachyzoite-infected, untreated control mice developed signs of illness at 18 DPI. In contrast, mice treated with sulfadiazine showed no clinical signs up to 50 DPI. Although dexamethasone treatment was required to establish B. darlingi infection in outbred mice inoculated with opossum-derived B. darlingi bradyzoites, no such treatment was required for mice inoculated with culture-derived B. darlingi tachyzoites. Finally, sulfadiazine was highly

  9. Experimental infection of a North American raptor, American kestrel (Falco sparverius), with highly pathogenic avian influenza virus (H5N1)

    Science.gov (United States)

    Hall, Jeffrey S.; Ip, Hon S.; Franson, J.C.; Meteyer, C.; Nashold, Sean W.; Teslaa, Joshua L.; French, J.; Redig, P.; Brand, C.

    2009-01-01

    Several species of wild raptors have been found in Eurasia infected with highly pathogenic avian influenza virus (HPAIV) subtype H5N1. Should HPAIV (H5N1) reach North America in migratory birds, species of raptors are at risk not only from environmental exposure, but also from consuming infected birds and carcasses. In this study we used American kestrels as a representative species of a North American raptor to examine the effects of HPAIV (H5N1) infection in terms of dose response, viral shedding, pathology, and survival. Our data showed that kestrels are highly susceptible to HPAIV (H5N1). All birds typically died or were euthanized due to severe neurologic disease within 4-5 days of inoculation and shed significant amounts of virus both orally and cloacally, regardless of dose administered. The most consistent microscopic lesions were necrosis in the brain and pancreas. This is the first experimental study of HPAIV infection in a North American raptor and highlights the potential risks to birds of prey if HPAIV (H5N1) is introduced into North America.

  10. Efficacy of linezolid, teicoplanin, and vancomycin in prevention of an experimental polytetrafluoroethylene graft infection model caused by methicillin-resistant Staphylococcus aureus.

    Science.gov (United States)

    Mese, Bulent; Bozoglan, Orhan; Elveren, Serdal; Eroglu, Erdinc; Gul, Mustafa; Celik, Ahmet; Ciralik, Harun; Yildirimdemir, Halil Ibrahim; Yasim, Alptekin

    2015-03-27

    The aim of this study was to evaluate the effectiveness of linezolid, teicoplanin, and vancomycin in prevention of prosthetic vascular graft infections in a vascular graft infection model. Fifty rats were divided into 5 groups. A polytetrafluoroethylene graft was implanted on the back of each rat. Methicillin-resistant Staphylococcus aureus (MRSA) strain was inoculated into all rats except Group 1. Group 2 was not given any treatment, Group 3 received linezolid, Group 4 received vancomycin, and Group 5 received teicoplanin. The grafts were removed for microbiological and histological examinations on the 7th day. In addition, C-reactive protein and prealbumin levels and leukocyte counts in obtained blood specimens were determined. Group 1 did not have infection. Group 2 had bacteria 5.7 × 10(4) CFU/cm(2). Group 3 and Group 4 had less bacterial growth. Group 5 had no bacterial growth. The number of bacteria was significantly higher in Group 2 than in the other experimental groups and the control group (pprevention of prosthetic vascular graft infections.

  11. Experimental infection of broiler chicks with Salmonella Typhimurium from pigeon (Columba livia

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    Átilla Holanda de Albuquerque

    2016-08-01

    Full Text Available Several cases of animal and human salmonellosis caused by the Salmonella serotype Typhimurium have been reported. In animals, subclinical infection favors pathogen dissemination through feces. In this context, the domestic pigeon (Columba livia with an asymptomatic condition may play an important role in the transmission of salmonellosis, through the elimination of contaminated feces in commercial aviaries or in poultry feed facilities, causing economic losses to the poultry industry and presenting a risk to public health. This study aimed to evaluate the mortality, clinical signs and the presence of Salmonella Typhimurium in the feces and organs of chicks previously inoculated with bacteria isolated from a pigeon. One-day-old chicks were distributed in two experimental groups (G1 and G2 of 32 birds each, and a control group of six birds. Two inocula of 0.4 and 0.7 mL with 105 and 106 colony forming units were used in G1 and G2 birds, respectively. At 1, 4, 7 and 14 days post-inoculation (dpi fecal samples were pooled from each cage and individual cloacal swabs were collected. At 14 dpi, all chicks were euthanized and samples were collected from the liver, spleen, lung, cecum and intestine for microbiological analysis. Mortality was only observed among G2 birds (6.25%. Most birds presented clinical signs of diarrhea at 4 dpi and no symptom as observed at 14 dpi. The results from cloacal swabs demonstrated bacterial elimination in 68.8% and 53.1% of G2 and G1 birds, respectively at 1 dpi. Additionally, fecal samples had elevated bacterial shedding in all four periods of observation , with a higher excretion at 4 dpi (62.5% for both groups. Among G2 birds, 74.2% were positive for the pathogen in the intestine; G1 birds presented the lowest rate of lung infection (29%, and both groups had more than 50% positivity for liver and caeca. The results revealed that infected chicks with a Salmonella Typhimurium strains isolated from pigeons may host the

  12. Larval recovery of Toxocara cati in experimentally infected Rattus norvegicus and analysis of the rat as potential reservoir for this ascarid

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    Sérgio V Santos

    2009-09-01

    Full Text Available Toxocara cati is a common feline parasite transmitted by the ingestion of embryonated eggs, by the transmammary route or by predation of paratenic hosts harbouring third-stage larvae in their bodies. In the present study, the larval distribution of T. cati in tissues and organs of Rattus norvegicus experimentally infected with 300 embryonated eggs was analysed. Third-stage larvae were recovered from livers, lungs, kidneys, eyes, brains and carcasses of infected rats, following tissue digestion with HCl 0.5% for 24 h at 37°C. Some differences from the known larval distribution of Toxocara canisin the same rodent species were found.

  13. Experimental infection with different bacterial strains in larvae and juvenile Litopenaeus vannamei reared in Santa Catarina State, Brazil - doi: 10.4025/actascibiolsci.v32i3.5471 Experimental infection with different bacterial strains in larvae and juvenile Litopenaeus vannamei reared in Santa Catarina State, Brazil - doi: 10.4025/actascibiolsci.v32i3.5471

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    Adolfo Jatoba

    2010-09-01

    Full Text Available This study evaluated the pathogenic characteristics of bacteria isolated from Litopenaeus vannamei during an outbreak at the Laboratory of Marine Shrimp, UFSC, Santa Catarina State, Brazil. Their virulence potential in larvae and juvenile shrimp and the effects on the total haemocyte count, phenoloxidase activity and serum agglutinate titre were examined after experimental infection. Bacterial strains were isolated from larvae and adult shrimps, identified by the AP120E biochemical system as: two strains of Vibrio alginolyticus, three of Aeromonas salmonicida and one of Pasteurella multocida sp. and Pasteurella sp. All the bacterial strains isolated in this study caused mortality in shrimp. One strain of V. alginolyticus was responsible for 97.3 and 88.7% mortality in larvae and juvenil shrimps, respectively. The shrimp immunological system was influenced by experimental infection with V. alginolyticus. Decrease in the total haemocyte count and increase in the phenoloxidase activity and the serum agglutinate titre (p V. alginolyticus isolated from larvae and juvenile reared marine shrimp.This study evaluated the pathogenic characteristics of bacteria isolated from Litopenaeus vannamei during an outbreak at the Laboratory of Marine Shrimp, UFSC, Santa Catarina State, Brazil. Their virulence potential in larvae and juvenile shrimp and the effects on the total haemocyte count, phenoloxidase activity and serum agglutinate titre were examined after experimental infection. Bacterial strains were isolated from larvae and adult shrimps, identified by the AP120E biochemical system as: two strains of Vibrio alginolyticus, three of Aeromonas salmonicida and one of Pasteurella multocida sp. and Pasteurella sp. All the bacterial strains isolated in this study caused mortality in shrimp. One strain of V. alginolyticus was responsible for 97.3 and 88.7% mortality in larvae and juvenil shrimps, respectively. The shrimp immunological system was influenced by

  14. Ultrastructural study on experimental infection of rotavirus in a murine heterologous model

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    Selma Majerowicz

    1994-09-01

    Full Text Available Viral replication, histopathological and ultrastructural changes were observed for a period of nine days in the small intestine of suckling mice infected with a simian rotavirus (SA11. Samples taken from duodenum, jejunun and ileum were prepared for light microscopy, transmission and scanning electron microscopy analysis. Histopathologic effect could be detected within 8 hr post-infection, when only a few altered cells were observed. Damage was extensive after 16 hr post-infection, showing swollen enterocytes and reduced and irregularly oriented microvilli at intestinal villi tips. Virus particles were detected at 16 and 48 hr post-infection, budding from the viroplasm into the rough endoplasmic reticulum cisternae in ileum enterocytes. Clear evidence of viral replication, observed by electron microscopy was not described before in heterologous murine models. Regeneration of the intestinal villi began at the third day post-infection. Despite some differences observed in clinical symptoms and microscopic analysis of homologous and heterologous rotavirus infections, we concluded that mechanisms of heterologous rotavirus infection in mice follow similar patterns to those observed in the homologous models.

  15. Immunoglobulin subclass in experimental murine Toxocara cati infection

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    Kusnoto

    2017-11-01

    Full Text Available Aim: The aim of this study was to detect specific immunoglobulin (Ig that could be used to determine monoclonal antibody in conjugate-making an effort for the indirect enzyme-linked immunosorbent assay (ELISA diagnostic kit of toxocariasis in human. Materials and Methods: The study was conducted to assess the Ig profile, based on ELISA-isotyping, in mice infected with second stage larvae eggs of Toxocara cati. The optical density values of anti-T. cati mice serum IgG subclasses were analyzed by applying ANOVA factorial. Results: The specific IgG subclass in mice infected with T. cati mice was found to be IgG2β. Conclusion: Subclass of IgG, especially IgG2β, can provide leads about the use of the monoclonal antibody in conjugate making an effort for the indirect ELISA diagnostic kit.

  16. Influence of Multiple Infection and Relatedness on Virulence: Disease Dynamics in an Experimental Plant Population and Its Castrating Parasite

    Science.gov (United States)

    Buono, Lorenza; López-Villavicencio, Manuela; Shykoff, Jacqui A.; Snirc, Alodie; Giraud, Tatiana

    2014-01-01

    The level of parasite virulence, i.e., the decrease in host's fitness due to a pathogen, is expected to depend on several parameters, such as the type of the disease (e.g., castrating or host-killing) and the prevalence of multiple infections. Although these parameters have been extensively studied theoretically, few empirical data are available to validate theoretical predictions. Using the anther smut castrating disease on Silene latifolia caused by Microbotryum lychnidis-dioicae, we studied the dynamics of multiple infections and of different components of virulence (host death, non-recovery and percentage of castrated stems) during the entire lifespan of the host in an experimental population. We monitored the number of fungal genotypes within plants and their relatedness across five years, using microsatellite markers, as well as the rates of recovery and host death in the population. The mean relatedness among genotypes within plants remained at a high level throughout the entire host lifespan despite the dynamics of the disease, with recurrent new infections. Recovery was lower for plants with multiple infections compared to plants infected by a single genotype. As expected for castrating parasites, M. lychnidis-dioicae did not increase host mortality. Mortality varied across years but was generally lower for plants that had been diseased the preceding year. This is one of the few studies to have empirically verified theoretical expectations for castrating parasites, and to show particularly i) that castrated hosts live longer, suggesting that parasites can redirect resources normally used in reproduction to increase host lifespan, lengthening their transmission phase, and ii) that multiple infections increase virulence, here in terms of non-recovery and host castration. PMID:24892951

  17. [Genotyping and evaluation of infection dynamics in a Colombian isolate of Leptospira santarosai in hamster as an experimental model].

    Science.gov (United States)

    Agudelo-Flórez, Piedad; Durango, Harold; Aranzazu, Diego; Rodas, Juan David; Travi, Bruno

    2014-01-01

    Is necessary to develop models for the study of leptospirosis. To genotype a Colombian strain of Leptospira isolated from a human with Weil´s syndrome and to evaluate its infection dynamics in the hamster experimental model. Genotyping was performed by amplification and sequence analysis of the rrs 16S and lipL32 genes. The median lethal dose was determined in intraperitoneally inoculated hamsters. The patterns of clinical chemistry, the duration of leptospiremia, leptospiruria and pathological findings were studied and compared in the same animal model infected with L. interrogans (Fiocruz L1-130). Molecular typing revealed that the isolate corresponded to the pathogenic species L. santarosai, which was recovered from hamsters´ kidneys and lungs and detected by lipL32 PCR from day 3 post-infection in these organs. There was a marked increase of C-reactive protein in animals at day 5 post-infection (3.25 mg/dl; normal value: 0.3 mg/dl) with decreases by day 18 (2.60 mg/dl: normal value: 0.8 mg/dl). Biomarkers of urea showed changes consistent with possible renal acute failure (day 5 post-infection: 49.01 mg/dl and day 18 post-infection: 53.71 mg/dl). Histopathological changes included interstitial pneumonia with varying degrees of hemorrhage and interstitial nephritis. The pathogenic species L. santarosai was identified in Colombia. Its pathogenicity as determined by tropism to lung and kidney was comparable to that of L. interrogans Fiocruz L1-130, well known for its virulence and pulmonar tropism. The biological aspects studied here had never before been evaluated in an autochthonous isolate.

  18. Pathogenesis and immune response in Atlantic salmon (Salmo salar L.) parr experimentally infected with salmon pancreas disease virus (SPDV).

    Science.gov (United States)

    Desvignes, L; Quentel, C; Lamour, F; le, Ven A

    2002-01-01

    Atlantic salmon parr were injected intraperitoneally with salmon pancreas disease virus (SPDV) grown on CHSE-214 cells. The viraemia, the histopathological changes in target organs and some immune parameters were taken at intervals up to 30 days post-infection (dpi). The earliest kind of lesion was necrosis of exocrine pancreas, appearing as soon as 2 dpi. It progressed towards complete tissue breakdown at 9 dpi before resolving gradually. Concurrent to this necrosis, a strong inflammatory response was in evidence from 9 dpi in the pancreatic area for a majority of fish. A necrosis of the myocardial cells of the ventricle occurred in infected fish mainly at 16 dpi and it faded thereafter. The monitoring of the plasma viral load showed a rapid haematogenous spreading of SPDV, peaking at 4 dpi, but also the absence of a secondary viraemia. No interferon (IFN) was detected following the infection of parr with SPDV, probably owing to an IFN activity in Atlantic salmon below the detection level of the technique. Neutralising antibodies against SPDV were in evidence from 16 dpi and they showed a time-related increasing titre and prevalence. The phagocytic activity in head-kidney leucocytes was always significantly higher in the infected fish than in the control fish, being particularly high by 9 dpi. Lysozyme and complement levels were both increased and they peaked significantly in the infected fish at 9 and 16 dpi respectively. These results demonstrated that an experimental infection of Atlantic salmon parr with SPDV provoked a stimulation of both specific and non-specific immunity with regards to the viraemia and the histopathology.

  19. Understanding Experimental LCMV Infection of Mice: The Role of Mathematical Models

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    Gennady Bocharov

    2015-01-01

    Full Text Available Virus infections represent complex biological systems governed by multiple-level regulatory processes of virus replication and host immune responses. Understanding of the infection means an ability to predict the systems behaviour under various conditions. Such predictions can only rely upon quantitative mathematical models. The model formulations should be tightly linked to a fundamental step called “coordinatization” (Hermann Weyl, that is, the definition of observables, parameters, and structures that enable the link with a biological phenotype. In this review, we analyse the mathematical modelling approaches to LCMV infection in mice that resulted in quantification of some fundamental parameters of the CTL-mediated virus control including the rates of T cell turnover, infected target cell elimination, and precursor frequencies. We show how the modelling approaches can be implemented to address diverse aspects of immune system functioning under normal conditions and in response to LCMV and, importantly, make quantitative predictions of the outcomes of immune system perturbations. This may highlight the notion that data-driven applications of meaningful mathematical models in infection biology remain a challenge.

  20. ITIH4 (inter-alpha-trypsin inhibitor heavy chain 4) is a new acute-phase protein isolated from cattle during experimental infection

    DEFF Research Database (Denmark)

    Pineiro, M.; Andres, M.; Iturralde, M.

    2004-01-01

    We have isolated from calf serum a protein with an apparent M, of 120,000. The protein was detected by using antibodies against major acute-phase protein in pigs with acute inflammation. The amino acid sequence of an internal fragment revealed that this protein is the bovine counterpart of ITIH4......, and Peptostreptococcus indolicus to induce an acute-phase reaction. All animals developed moderate to severe clinical mastitis and exhibited remarkable increases in ITIH4 concentration in serum (from 3 to 12 times the initial values, peaking at 48 to 72 h after infection) that correlated with the severity of the disease....... Animals with experimental infections with bovine respiratory syncytial virus (BRSV) also showed increases in ITIH4 concentration (from two- to fivefold), which peaked at around 7 to 8 days after inoculation. Generally, no response was seen after a second infection of the same animals with the virus...

  1. Experimental infection of laying hens with Salmonella enterica serovar Gallinarum Infecção experimental com Salmonella enterica serovar Gallinarum em poedeiras comerciais

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    Gláucia Helaine de Oliveira

    2005-03-01

    Full Text Available Experimental infections were set up in commercial laying birds, comprising a white relatively resistant line and a red susceptible line infecting with Salmonella enterica serovar Gallinarum. The major findings were that in susceptible birds clinical disease occurred in a dose-dependent manner. Faecal excretion occurred in susceptible birds almost up to death but also occurred in the more resistant line and in birds, which were convalescing. Removal of birds, which had died from the disease, from the environment, reduced the resultant mortality/morbidity and may be regarded as a useful measure for control.Infecções experimentais por Salmonella enterica serovar Gallinarum foram realizadas em aves de postura comercial, incluindo uma linhagem branca resistente e uma linhagem vermelha susceptível ao desenvolvimento da enfermidade clínica. As aves de linhagem susceptível apresentaram doença clínica dependente da dose administrada. Excreção fecal foi observada em aves da linhagem susceptível próximo ao momento da morte e, eventualmente, em aves da linhagem resistente e aves convalescentes. A remoção das aves mortas do meio ambiente reduziu a taxa de mortalidade/morbidade, procedimento este que pode ser utilizado como medida de controle.

  2. Experimental infection of highly pathogenic avian influenza virus H5N1 in black-headed gulls (Chroicocephalus ridibundus).

    Science.gov (United States)

    Ramis, Antonio; van Amerongen, Geert; van de Bildt, Marco; Leijten, Loneke; Vanderstichel, Raphael; Osterhaus, Albert; Kuiken, Thijs

    2014-08-19

    Historically, highly pathogenic avian influenza viruses (HPAIV) rarely resulted in infection or clinical disease in wild birds. However, since 2002, disease and mortality from natural HPAIV H5N1 infection have been observed in wild birds including gulls. We performed an experimental HPAIV H5N1 infection of black-headed gulls (Chroicocephalus ridibundus) to determine their susceptibility to infection and disease from this virus, pattern of viral shedding, clinical signs, pathological changes and viral tissue distribution. We inoculated sixteen black-headed gulls with 1 × 10(4) median tissue culture infectious dose HPAIV H5N1 (A/turkey/Turkey/1/2005) intratracheally and intraesophageally. Birds were monitored daily until 12 days post inoculation (dpi). Oropharyngeal and cloacal swabs were collected daily to detect viral shedding. Necropsies from birds were performed at 2, 4, 5, 6, 7, and 12 dpi. Sampling from selected tissues was done for histopathology, immunohistochemical detection of viral antigen, PCR, and viral isolation. Our study shows that all inoculated birds were productively infected, developed systemic disease, and had a high morbidity and mortality rate. Virus was detected mainly in the respiratory tract on the first days after inoculation, and then concentrated more in pancreas and central nervous system from 4 dpi onwards. Birds shed infectious virus until 7 dpi from the pharynx and 6 dpi from the cloaca. We conclude that black-headed gulls are highly susceptible to disease with a high mortality rate and are thus more likely to act as sentinel species for the presence of the virus than as long-distance carriers of the virus to new geographical areas.

  3. Assessment of PCR in the detection of Leishmania spp in experimentally infected individual phlebotomine sandflies (Diptera: Psychodidae: Phlebotominae

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    MICHALSKY Érika M.

    2002-01-01

    Full Text Available DNA amplification by the polymerase chain reaction (PCR was applied in the investigation of the presence of Leishmania (Kinetoplastida: Trypanosomatidae parasites in single phlebotomine sandflies. Three phlebotomine/parasite pairs were used: Lutzomyia longipalpis/Leishmania chagasi, Lutzomyia migonei/Leishmania amazonensis and Lutzomyia migonei/Leishmania braziliensis, all of them incriminated in the transmission of visceral or cutaneous leishmaniasis. DNA extraction was performed with whole insects, with no need of previous digestive tract dissection or pooling specimens. The presence of either mouse blood in the digestive tract of the sandflies or the digestive tract itself did not interfere in the PCR. Infection by as few as 10 Leishmania sp. per individual were sufficient for DNA amplification with genus-specific primers. Using primers for L. braziliensis and L. mexicana complexes, respectively, it was possible to discriminate between L. braziliensis and L. amazonensis in experimentally infected vectors (L. migonei.

  4. Genital tract lesions in sexually mature Göttingen minipigs during the initial stages of experimental vaginal infection with Chlamydia trachomatis serovar D.

    Science.gov (United States)

    Erneholm, Karin; Lorenzen, Emma; Bøje, Sarah; Olsen, Anja Weinreich; Andersen, Peter; Cassidy, Joseph P; Follmann, Frank; Jensen, Henrik E; Agerholm, Jørgen S

    2016-09-10

    Chlamydia is one of the most common sexually transmitted diseases in humans worldwide, causing chronic lesions in the reproductive tract. Due to its often asymptomatic course, there is limited knowledge about the initial changes in the genital tract following infection. This study employs a novel sexually mature minipig model to investigate the initial histopathological changes following vaginal infection with Chlamydia trachomatis serovar D. A vaginal inoculation resulted in an infection primarily affecting the lower genital tract. The histopathological changes were characterized by a subepithelial inflammation consisting of neutrophils and mononuclear cells, followed by an increase in the number of plasma cells within the sub-epithelial stroma of the vagina. Detection of Chlamydia was associated with expression of cyclooxygenase-2 and interleukin-8 by superficial epithelial cells. The infection was self-limiting, with a duration of 7 days. Neutrophils, plasma cells and IL-8 have been linked with Chlamydia genital infection of unknown duration in human patients. In this study, we observe a similar pattern of local immune response/inflammation following experimental inoculation suggesting this porcine model shows promise as a model for translational chlamydia research.

  5. Trypanosoma cruzi in marsupial didelphids (Philander frenata and Didelhis marsupialis: differences in the humoral immune response in natural and experimental infections

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    Legey Ana Paula

    2003-01-01

    Full Text Available Philander frenata and Didelphis marsupialis harbor parasitism by Trypanosoma cruzi without developing any apparent disease and on the contrary to D. marsupialis, P. frenata maintains parasitism by T. cruzi II subpopulations. Here we compared the humoral immune response of the two didelphids naturally and experimentally infected with T. cruzi II group, employing SDS-PAGE/Western blot techniques and by an Indirect immunofluorescence assay. We also studied the histopathological pattern of naturally and experimentally infected P. frenata with T. cruzi. P. frenata sera recognized more antigens than D. marsupialis, and the recognition pattern did not show any change over the course of the follow up of both didelphid species. Polypeptides of 66 and 90kDa were the most prominent antigens recognized by both species in the soluble and enriched membrane fractions. P. frenata recognized intensely also a 45kDa antigen. Our findings indicate that: 1 there were no quantitative or qualitative differences in the patent or subpatent phases in the recognition pattern of P. frenata; 2 the significant differences in the recognition pattern of parasitic antigens by P. frenata and D. marsupialis sera suggest that they probably "learned" to live in harmony with T. cruzi by different strategies; 3 although P. frenata do not display apparent disease, tissular lesions tended to be more severe than has been described in D. marsupialis; and 4 Both didelphids probably acquired infection by T. cruzi after their evolutionary divergence.

  6. Evaluation of tulathromycin for the treatment of pneumonia following experimental infection of swine with Mycoplasma hyopneumoniae.

    Science.gov (United States)

    McKelvie, Jo; Morgan, Jeremy H; Nanjiani, Ian A; Sherington, John; Rowan, Tim G; Sunderland, Simon J

    2005-01-01

    Tulathromycin was evaluated in the treatment of pneumonia in weaned pigs inoculated intranasally with Mycoplasma hyopneumoniae. Five days postchallenge, the pigs were randomized to treatment with a single IM administration of saline, a single IM administration of tulathromycin (2.5 mg/kg; day 0), or three IM administrations of enrofloxacin (5.0 mg/kg; days 0, 1, 2). Pigs were necropsied on day 12 or 13. Unchallenged controls remained healthy with no lung pathology. Compared with saline, coughing, mean lung lesion score, and proportional lung weight were significantly reduced and weight gain was significantly greater for tulathromycin-treated pigs (P pigs (P treatment of pneumonia following experimental infection with M. hyopneumoniae.

  7. Performance of the ELISA test for the diagnosis of cysticercosis using experimentally and naturally cattle infected with metacestode of Taenia saginata

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    Rafaella Paola Meneguete dos Guimarães-Peixoto

    2015-04-01

    Full Text Available The bovine taeniasis-cysticercosis complex can be defined as a set of pathological changes caused by the adult form of Taenia saginata in humans and their larval form in animals (Cysticercus bovis. Data on the occurrence of bovine cysticercosis comes from the records of veterinary inspection of meat in slaughterhouses under fiscalization, where some positive cases may go unnoticed, especially in moderate infections. So, it is relevant the use of serological tests that have greater sensitivity than the post-mortem routine exams. Studies have shown the possible application of the ELISA test as a tool for epidemiological studies of the parasitosis and in the identification of animals with cysts. The aim of this study is to determine the detection threshold of the indirect ELISA test, using experimentally and naturally infected animals in detecting cases of cysticercosis. The sensitivity of the test to naturally infected animals using a cut-off 1 and 2 added with 2 standart-deviation (SD was of 12% and 24.4%, respectively. However, when using the cut-off of 1 and 2 added with 3 SD, the test sensitivity dropped, represented by 14.4% and 1.99% of the test sensitivity. As for the samples from experimentally infected animals, using the cut-off 1 and 2 added with 2 SD the sensitivity was 55.9% and 92.5%; and adding 3 SD the values found were 31.2% and 86%, respectively. The specificity of the test in all situations tested was 100%. It is important to take into account the right choice of control sera used in the ELISA test, whereas, according to its application, it is necessary to increase the sensitivity or specificity.

  8. Role of the chemokine receptors CCR1, CCR2 and CCR4 in the pathogenesis of experimental dengue infection in mice.

    Directory of Open Access Journals (Sweden)

    Rodrigo Guabiraba

    Full Text Available Dengue virus (DENV, a mosquito-borne flavivirus, is a public health problem in many tropical countries. Recent clinical data have shown an association between levels of different chemokines in plasma and severity of dengue. We evaluated the role of CC chemokine receptors CCR1, CCR2 and CCR4 in an experimental model of DENV-2 infection in mice. Infection of mice induced evident clinical disease and tissue damage, including thrombocytopenia, hemoconcentration, lymphopenia, increased levels of transaminases and pro-inflammatory cytokines, and lethality in WT mice. Importantly, infected WT mice presented increased levels of chemokines CCL2/JE, CCL3/MIP-1α and CCL5/RANTES in spleen and liver. CCR1⁻/⁻ mice had a mild phenotype with disease presentation and lethality similar to those of WT mice. In CCR2⁻/⁻ mice, lethality, liver damage, levels of IL-6 and IFN-γ, and leukocyte activation were attenuated. However, thrombocytopenia, hemoconcentration and systemic TNF-α levels were similar to infected WT mice. Infection enhanced levels of CCL17/TARC, a CCR4 ligand. In CCR4⁻/⁻ mice, lethality, tissue injury and systemic inflammation were markedly decreased. Despite differences in disease presentation in CCR-deficient mice, there was no significant difference in viral load. In conclusion, activation of chemokine receptors has discrete roles in the pathogenesis of dengue infection. These studies suggest that the chemokine storm that follows severe primary dengue infection associates mostly to development of disease rather than protection.

  9. Infecção experimental pelo Encephalitozoon cuniculi em camundongos imunossuprimidos com dexametasona Experimental Encephalitozoon cuniculi infection in dexamethasone-immunosuppressed mice

    Directory of Open Access Journals (Sweden)

    Maria Anete Lallo

    2002-10-01

    study was to develop pharmacologically immunosuppressed animals as a model of the natural occurring E. cuniculi infection. METHODS: Distint groups of adult Balb-C mice were immunosuppressed with different doses of dexamethasone (Dx, 3 or 5 mg/kg/day, intraperitoneal route - IP and inoculated with E. cuniculi spores by IP route intraperitoneally. Control groups (inoculated animals but non-immunosuppressed and non- inoculated animals but immunosuppressed were also used. The spores of E. cuniculi were previously cultivated in MDCK cells. The animals were sacrificed and necropsied at 7, 14, 21, 28 and 35 days post-inoculation. Tissue fragments were collected and processed for light microscopy studies, using Gram-chromotrope and hematoxylin-eosin staining techniques. RESULTS: In all immunosupressed and inoculated inoculated immunosuppressed mice,specially in those that received 5 mg/kg/day of dexamethasone, the most prominent necropsy findings were hepatomegaly and splenomegaly. The experimental inoculation resulted in a disseminated non-lethal infection, characterized by granulomatous lesions in several organs (liver, lungs, kidneys, gut and brain but notably in the hepatic tissue. Spores of E. cuniculi were only seen in few animals treated with 5 mg/kg/day of Dx at 35 days post-infection. CONCLUSIONS: Microsporidiosis in Dx-immunosuppressed mice provides a useful model for studies of the microsporidial infection, resembling that one naturally occurring in immunodeficient individuals with AIDS.

  10. Impact of the post-weaning nutritional history on the response to an experimental Haemonchus contortus infection in Creole goats and Black Belly sheep.

    Science.gov (United States)

    Ceï, W; Salah, N; Paut, C; Dumoulin, P-J; Arquet, R; Félicité, Y; Alexandre, G; Archimède, H; Bambou, J-C

    2016-03-15

    In small ruminants, the response against gastrointestinal nematode (GIN) infections is influenced not only by the host genotype and the physiological stage but also by environmental factors, particularly the nutritional status at the time of infection. In this study we evaluated the long-term effect and the interaction between the host species and the nutritional history on the response to GIN infection in two animal models differing in their phenotypic growth and their level of GIN resistance: Black Belly sheep and Creole goats. Lambs and kids were subjected to three distinct nutritional conditions at weaning: low dietary conditions (100% of the theoretical energy requirement for maintenance, corresponding to 548v. 484KJ/Kg BW(0.75) for lambs and kids respectively and 6% of crude protein, CP), medium dietary conditions (150% of the theoretical energy requirement for maintenance and 13% CP) and high dietary conditions (200% of the theoretical energy requirement for maintenance and 20% CP). This 3-months period was followed by a 1-month period on the medium dietary conditions for all the animals before an experimental Haemonchus contortus infection. We monitored the impact of the nutritional history (nutritional condition after weaning), on the intensity of the GIN infection by measuring individual faecal egg counts (FEC), growth rate (ADG), blood eosinophil counts and other pathophysiological parameters. The FEC, growth rate and blood eosinophil counts were significantly affected by the nutritional history in lambs but not in kids. The lowest FEC was found for lambs placed in high dietary conditions, however during the same period body weight loss was observed in this group. In low dietary conditions, kids were more resistant than lambs and the ADG was higher in lambs. However, the anaemia and the level of serum pepsinogen, marker of the abomasal mucosa integrity, were higher in kids. Our data suggest that the impact of the post-weaning nutritional history on the

  11. Streptococcus agalactiae impairs cerebral bioenergetics in experimentally infected silver catfish.

    Science.gov (United States)

    Baldissera, Matheus D; Souza, Carine F; Parmeggiani, Belisa S; Santos, Roberto C V; Leipnitz, Guilhian; Moreira, Karen L S; da Rocha, Maria Izabel U M; da Veiga, Marcelo L; Baldisserotto, Bernardo

    2017-10-01

    It is becoming evident that bacterial infectious diseases affect brain energy metabolism, where alterations of enzymatic complexes of the mitochondrial respiratory chain and creatine kinase (CK) lead to an impairment of cerebral bioenergetics which contribute to disease pathogenesis in the central nervous system (CNS). Based on this evidence, the aim of this study was to evaluate whether alterations in the activity of complex IV of the respiratory chain and CK contribute to impairment of cerebral bioenergetics during Streptococcus agalactiae infection in silver catfish (Rhamdia quelen). The activity of complex IV of the respiratory chain in brain increased, while the CK activity decreased in infected animals compared to uninfected animals. Brain histopathology revealed inflammatory demyelination, gliosis of the brain and intercellular edema in infected animals. Based on this evidence, S. agalactiae infection causes an impairment in cerebral bioenergetics through the augmentation of complex IV activity, which may be considered an adaptive response to maintain proper functioning of the electron respiratory chain, as well as to ensure ongoing electron flow through the electron transport chain. Moreover, inhibition of cerebral CK activity contributes to lower availability of ATP, contributing to impairment of cerebral energy homeostasis. In summary, these alterations contribute to disease pathogenesis linked to the CNS. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Replication and clearance of respiratory syncytial virus - Apoptosis is an important pathway of virus clearance after experimental infection with bovine respiratory syncytial virus

    DEFF Research Database (Denmark)

    Viuff, B.; Tjørnehøj, Kirsten; Larsen, Lars Erik

    2002-01-01

    and clearance in a natural target animal. Replication of BRSV was demonstrated in the luminal part of the respiratory epithelial cells and replication in the upper respiratory tract preceded the replication in the lower respiratory tract. Virus excreted to the lumen of the respiratory tract was cleared...... and the infections with human respiratory syncytial. virus and BRSV have similar clinical, pathological, and epidemiological characteristics. In this study we used experimental BRSV infection in calves as a model of respiratory syncytial virus infection to demonstrate important aspects of viral replication......Human respiratory syncytial virus is an important cause of severe respiratory disease in young children, the elderly, and in immunocompromised adults. Similarly, bovine respiratory syncytial virus (BRSV) is causing severe, sometimes fatal, respiratory disease in calves. Both viruses are pneumovirus...

  13. Experimental infection of a North American raptor, American Kestrel (Falco sparverius, with highly pathogenic avian influenza virus (H5N1.

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    Jeffrey S Hall

    2009-10-01

    Full Text Available Several species of wild raptors have been found in Eurasia infected with highly pathogenic avian influenza virus (HPAIV subtype H5N1. Should HPAIV (H5N1 reach North America in migratory birds, species of raptors are at risk not only from environmental exposure, but also from consuming infected birds and carcasses. In this study we used American kestrels as a representative species of a North American raptor to examine the effects of HPAIV (H5N1 infection in terms of dose response, viral shedding, pathology, and survival. Our data showed that kestrels are highly susceptible to HPAIV (H5N1. All birds typically died or were euthanized due to severe neurologic disease within 4-5 days of inoculation and shed significant amounts of virus both orally and cloacally, regardless of dose administered. The most consistent microscopic lesions were necrosis in the brain and pancreas. This is the first experimental study of HPAIV infection in a North American raptor and highlights the potential risks to birds of prey if HPAIV (H5N1 is introduced into North America.

  14. Freeze-tolerance of Trichinella muscle larvae in experimentally infected wild boars

    DEFF Research Database (Denmark)

    Lacour, Sandrine A.; Heckmann, Aurelie; Mace, Pauline

    2013-01-01

    served as negative controls. All wild boars were sacrificed 24 wpi. Muscle samples of 70 g were stored at -21 degrees C for 19,30 and 56h, and for 1-8 weeks. Larvae were recovered by artificial digestion. Their mobilities were recorded using Saisam (R) image analysis software and their infectivities were......Freeze-tolerance of encapsulated Trichinella muscle larvae (ML) is mainly determined by Trichinella species, but is also influenced by host species, the age of the infection and the storage time and temperature of the infected meat. Moreover, the freeze-tolerance of the encapsulated species appears...... to be correlated to the development of thick capsule walls which increases with age. An extended infection period and the muscle composition in some hosts (e.g. herbivores) may provide freeze-avoiding matrices due to high carbohydrate contents. The present experiment compares freeze-tolerance of Trichinella...

  15. Experimental infection of Ethiopian highland sheep by different ...

    African Journals Online (AJOL)

    adult worm population and the egg excretion positively and significantly correlated together, whereas they were .... Figure 1: Nematode egg excretion from sheep infected with different doses of H. contortus L3. Total worm burden .... further drop in haematological parameters until the end of the experiment. Eosinophils are ...

  16. Immuno-pathological studies on broiler chicken experimentally infected with Escherichia coli and supplemented with neem (Azadirachta indica leaf extract

    Directory of Open Access Journals (Sweden)

    Vikash Sharma

    2016-07-01

    Full Text Available Aim: The present study was conducted to evaluate the effects of neem leaf extract (NLE supplementation on immunological response and pathology of different lymphoid organs in experimentally Escherichia coli challenged broiler chickens. Materials and Methods: For this study, we procured 192-day-old broiler chicks from local hatchery and divided them into Groups A and Group B containing 96 birds each on the first day. Chicks of Group A were supplemented with 10% NLE in water, whereas chicks of Group B were not supplemented with NLE throughout the experiment. At 7th day of age, chicks of Group A were divided into A1 and A2 and Group B into B1 and B2 with 54 and 42 chicks, respectively, and chicks of Groups A1 and B1 were injected with E. coli O78 at 107 colony-forming units/0.5 ml intraperitoneally. Six chicks from each group were sacrificed at 0, 2, 4, 7, 14, 21, and 28 days post infection; blood was collected and thorough post-mortem examination was conducted. Tissue pieces of spleen and bursa of Fabricius were collected in 10% buffered formalin for histopathological examination. Serum was separated for immunological studies. Result: E. coli specific antibody titer was significantly higher in Group A1 in comparison to Group B1. Delayed-type hypersensitivity response against 2,4 dinirochlorobenzene (DNCB antigen was significantly higher in Group A1 as compared to Group B1. Pathological studies revealed that E. coli infection caused depletion of lymphocytes in bursa of Fabricius and spleen. Severity of lesions in Group A1 was significantly lower in comparison to Group B1. Conclusion: 10% NLE supplementation enhanced the humoral as well as cellular immune responses attributed to its immunomodulatory property in experimentally E. coli infected broiler chicken.

  17. Immuno-pathological studies on broiler chicken experimentally infected with Escherichia coli and supplemented with neem (Azadirachta indica) leaf extract.

    Science.gov (United States)

    Sharma, Vikash; Jakhar, K K; Dahiya, Swati

    2016-07-01

    The present study was conducted to evaluate the effects of neem leaf extract (NLE) supplementation on immunological response and pathology of different lymphoid organs in experimentally Escherichia coli challenged broiler chickens. For this study, we procured 192-day-old broiler chicks from local hatchery and divided them into Groups A and Group B containing 96 birds each on the first day. Chicks of Group A were supplemented with 10% NLE in water, whereas chicks of Group B were not supplemented with NLE throughout the experiment. At 7(th) day of age, chicks of Group A were divided into A1 and A2 and Group B into B1 and B2 with 54 and 42 chicks, respectively, and chicks of Groups A1 and B1 were injected with E. coli O78 at 10(7) colony-forming units/0.5 ml intraperitoneally. Six chicks from each group were sacrificed at 0, 2, 4, 7, 14, 21, and 28 days post infection; blood was collected and thorough post-mortem examination was conducted. Tissue pieces of spleen and bursa of Fabricius were collected in 10% buffered formalin for histopathological examination. Serum was separated for immunological studies. E. coli specific antibody titer was significantly higher in Group A1 in comparison to Group B1. Delayed-type hypersensitivity response against 2,4 dinirochlorobenzene (DNCB) antigen was significantly higher in Group A1 as compared to Group B1. Pathological studies revealed that E. coli infection caused depletion of lymphocytes in bursa of Fabricius and spleen. Severity of lesions in Group A1 was significantly lower in comparison to Group B1. 10% NLE supplementation enhanced the humoral as well as cellular immune responses attributed to its immunomodulatory property in experimentally E. coli infected broiler chicken.

  18. Ultrastructural study of liver and lead tissue concentrations in young mallard ducks (Anas platyrhynchos) after ingestion of single lead shot.

    Science.gov (United States)

    Pineau, Alain; Fauconneau, Bernard; Plouzeau, Eric; Fernandez, Béatrice; Quellard, Nathalie; Levillain, Pierre; Guillard, Olivier

    2017-01-01

    Lead (Pb) represents a serious threat to wildlife and ecosystems. The aim of this study was to examine the subcellular effects of dietary Pb pellet ingestion on mallard (Anas platyrhynchos) livers. After ingestion of a single Pb shot (LS4 size class: 0.177 ± 0.03 g) in 41 mallard ducks (22 males and 19 females) versus 10 controls (5 males and 5 females), all 7-week old, a morphologic study was conducted by TEM (transmission electron microscopy) of liver at the subcellular level. The results in treated mallards showed at a magnification of 2500 X that hepatic parenchyma was altered as evidenced by intralysosomal electron-dense deposits, which are compatible with Pb deposits. Further, at a higher magnification (15,000 X) in both genders, deterioration of mitochondria was observed in which the crests and, to a lesser extent, outer membrane were lysed. While the rough endoplasmic reticulum was fragmented, intracytoplasmic electron-dense material compatible with Pb deposits was maximally visible, thereby underscoring the deeply destructive effect of this metal on the subcellular architecture of the liver. In addition, applying an optimized and validated method in a clean room using electrothermal atomic absorption spectrophotometer (ETAAS) with Zeeman background correction, the objective was to improve and refine certain indispensable measurements pertaining to Pb impregnation in tissues other than liver such as kidneys, bones, and feathers of mallards. Data demonstrated show that compared with controls, Pb accumulation increases significantly, not only in the liver (3-fold), but also in the bones and the feathers (14-fold). No significant difference was noted between males and females. Bearing in mind the marked subcellular toxicity attributed to Pb, this study reinforces present-day arguments advocating limitation of game consumption.

  19. A consensus approach to vertebrate de novo transcriptome assembly from RNA-seq data: Assembly of the duck (Anas platyrhynchos transcriptome.

    Directory of Open Access Journals (Sweden)

    Joanna eMoreton

    2014-06-01

    Full Text Available For vertebrate organisms where a reference genome is not available, de novo transcriptome assembly enables a cost effective insight into the identification of tissue specific or differentially expressed genes and variation of the coding part of the genome. However, since there are a number of different tools and parameters that can be used to reconstruct transcripts, it is difficult to determine an optimal method. Here we suggest a pipeline based on (1 assessing the performance of three different assembly tools (2 using both single and multiple k-mer approaches (3 examining the influence of the number of reads used in the assembly (4 merging assemblies from different tools. We use an example dataset from the vertebrate Anas platyrhynchos domestica (Pekin duck. We find that taking a subset of data enables a robust assembly to be produced by multiple methods without the need for very high memory capacity. The use of reads mapped back to transcripts (RMBT and CEGMA (Core Eukaryotic Genes Mapping Approach provides useful metrics to determine the completeness of assembly obtained. For this dataset the use of multiple k-mers in the assembly generated a more complete assembly as measured by greater number of RMBT and CEGMA score. Merged single k-mer assemblies are generally smaller but consist of longer transcripts, suggesting an assembly consisting of fewer fragmented transcripts. We suggest that the use of a subset of reads during assembly allows the relatively rapid investigation of assembly characteristics and can guide the user to the most appropriate transcriptome for particular downstream use. Transcriptomes generated by the compared assembly methods and the final merged assembly are freely available for download at http://dx.doi.org/10.6084/m9.figshare.1032613.

  20. Salmonella Enteritidis experimental infection in chickens: Effects of ...

    African Journals Online (AJOL)

    STORAGESEVER

    2008-10-20

    Oct 20, 2008 ... challenge dose of Salmonella Enteritidis on detection of specific immunoglobulin G (IgG) ... Two groups of specific-pathogen-free chickens were infected ... Since chickens may be exposed to variable quantities ... A second group of 8 hens was orally .... where presence of serum antibodies by most birds that.

  1. Food additives and Hymenolepis nana infection: an experimental study.

    Science.gov (United States)

    El-Nouby, Kholoud A; Hamouda, Hala E; Abd El Azeem, Mona A; El-Ebiary, Ahmad A

    2009-12-01

    The effect of sodium benzoate (SB) on the pathogenesis of Hymenolepis nana (H. nana) and its neurological manifestations was studied in the present work. One hundred and thirty five mice were classified into three groups. GI: received SB alone. GII: received SB before & after infection with H. nana and GIII: infected with H. nana. All groups were subjected to parasitological, histopathological, immunohistochemical and biochemical assays. The results revealed a significant decrease in IL-4 serum level with a significant increase in gamma amino butyric acid (GABA) and decrease in zinc brain levels in GI, while GII showed non significant increase in IL-4 level that resulted in a highly significant increase in the mean number of cysticercoids and adult worms with delayed expulsion as compared to GIII. This was reflected on histopathological and immunohistochemical changes in the brain. Also, there was a highly significant increase in GABA and decrease in zinc brain levels in GII to the degree that induced behavioral changes. This emphasizes the possible synergistic effect of SB on the neurological manifestations of H. nana and could, in part, explain the increased incidence of behavioral changes in children exposed to high doses of SB and unfortunately have H. nana infection.

  2. Comparison of parasitological and productive traits of Criollo lambs native to the central Mexican Plateau and Suffolk lambs experimentally infected with Haemonchus contortus.

    Science.gov (United States)

    Alba-Hurtado, F; Romero-Escobedo, E; Muñoz-Guzmán, M A; Torres-Hernández, G; Becerril-Pérez, C M

    2010-09-20

    The study compares the parasitological and productive traits of Criollo lambs native to the central Mexican Plateau (CNCMP) and Suffolk (SU) lambs experimentally infected with Haemonchus contortus. CNCMP lambs (n=20) and SU lambs (n=15) were infected with L3 of H. contortus while five lambs of each genotype were kept as controls. Fecal egg count (FEC), packed cell volume (PCV), blood eosinophil number (BEN), ocular mucous membrane color (as measured by the FAMACHA index), changes in body condition score (BCS) and cumulative live weight gain (CLWG) were measured weekly during a 20-week period. On week 20, all animals were euthanized and the number of adult worms (AW) in the abomasum was counted. Infected SU lambs had higher (p<0.05) FEC and AW mean values compared to CNCMP lambs, which had a higher mean BEN count (p<0.05). Infected lambs had lower PCV values than controls, regardless of genotype, and had a negative correlation (r=-0.84, p<0.05) with the FAMACHA index. BCS tended to decline for infected SU lambs and increased slightly for infected CNCMP lambs. CLWG differed in all groups (p<0.05); infected SU lambs gained 12.1+/-1.9kg, infected CNCMP lambs gained 18.8+/-0.7kg, control SU lambs gained 34.6+/-1.6kg, and control CNCMP lambs gained 26.9+/-0.8kg. In conclusion, CNCMP lambs had a smaller worm burden, a better ability to maintain their productive traits, and were less affected by infection with Haemonchus contortus.

  3. Infective larvae of five Onchocerca species from experimentally infected Simulium species in an area of zoonotic onchocerciasis in Japan

    Directory of Open Access Journals (Sweden)

    Fukuda M.

    2008-06-01

    Full Text Available Microfilariae of five Onchocerca species, O. dewittei japonica (the causative agent of zoonotic onchocerciasis in Oita, Kyushu, Japan from wild boar (Sus scrofa, O. skrjabini and O. eberhardi from sika deer (Cervus nippon, O. lienalis from cattle, and an as yet unnamed Onchocerca sp. from wild boar, were injected intrathoracically into newly-emerged black flies of several species from Oita to search the potential vector(s of these parasites and identify their infective larvae. Development of O. dewittei japonica microfilariae to the infective larvae occurred in Simulium aokii, S. arakawae, S. bidentatum, S. japonicum, S. quinquestriatum, and S. rufibasis while development of infective larvae of O. skrjabini, O. eberhardi, and the unnamed Onchocerca sp. was observed in S. aokii, S. arakawae, and S. bidentatum. Development of O. lienalis microfilaria to infective larvae occurred in S. arakawae. Based on the morphology of infective larvae obtained, we proposed a key of identification of Onchocerca infective larvae found in Oita. We also reconsider the identification of three types of infective larvae previously recovered from Simulium species captured at cattle sheds: the large type I larvae that may be an undescribed species; the small type III identified as O. lienalis may include O. skrjabini too; the intermediary type II that may be O. gutturosa, or O. dewittei japonica, or the unnamed Onchocerca sp. of wild boar.

  4. Schmallenberg virus experimental infection of sheep

    DEFF Research Database (Denmark)

    Wernike, Kerstin; Hoffmann, Bernd; Bréard, Emmanuel

    2013-01-01

    production and diarrhoea for a few days. However, the knowledge about clinical signs and pathogenesis in adult sheep is limited.In the present study, adult sheep of European domestic breeds were inoculated with SBV either as cell culture grown virus or as virus with no history of passage in cell cultures...... 3–5 days by real-time RT-PCR. In total, 13 out of 30 inoculated sheep became RNAemic, with the highest viral load in animals inoculated with virus from low cell culture passaged or the animal passaged material. Contact animals remained negative throughout the study. One RNAemic sheep showed...... results in subclinical infection, transient RNAemia and a specific antibody response. Maintenance of viral RNA in the lymphoreticular system is observed for an extended period....

  5. Assessment of probiotics supplementation via feed or water on the growth performance, intestinal morphology and microflora of chickens after experimental infection with Eimeria acervulina, Eimeria maxima and Eimeria tenella.

    Science.gov (United States)

    Giannenas, I; Tsalie, E; Triantafillou, E; Hessenberger, S; Teichmann, K; Mohnl, M; Tontis, D

    2014-01-01

    In this study, the effect of probiotic supplementation via drinking water or feed on the performance of broiler chickens experimentally infected with sporulated oocysts of Eimeria acervulina (5 × 10(4)), Eimeria maxima and Eimeria tenella (2 × 10(4) each one) at 14 days of age was evaluated. Two hundred and forty 1-day-old Ross 308 male chicks were separated into eight equal groups with three replicates. Two of the groups, one infected with mixed Eimeria oocysts and the other not, were given a basal diet and served as controls. The remaining groups were also challenged with mixed Eimeria species and received the basal diet and either water supplemented with probiotic (three groups) or probiotic via feed (two groups); the probiotic used consisted of Enterococcus faecium #589, Bifidobacterium animalis #503 and Lactobacillus salivarius #505 at a ratio of 6:3:1. Probiotic supplementation was applied either via drinking water in different inclusion rates (groups W1, W2 and W3) or via feed using uncoated (group FN) or coated strains (group FC). The last group was given the basal diet supplemented with the anticoccidial lasalocid at 75 mg/kg. Each experimental group was given the corresponding diet or drinking water from day 1 to day 42 of age. Throughout the experimental period of 42 days, body weight and feed intake were recorded weekly and feed conversion ratios were calculated. Seven days after infection, the infected control group presented the lowest weight gain values, while probiotics supplied via feed supported growth to a comparable level with that of the lasalocid group. Probiotic groups presented lesion score values and oocyst numbers that were lower than in control infected birds but higher than in the lasalocid group. In the duodenum, jejunum and ileum, the highest villous height values were presented by probiotic groups. In conclusion, a mixture of probiotic substances gave considerable improvement in both growth performance and intestinal health in

  6. First study about the development of adult Echinococcus canadensis G6 genotype of goat origin in experimentally infected dogs.

    Science.gov (United States)

    Soriano, Silvia Viviana; Debiaggi, María Florencia; Pierangeli, Nora Beatriz; Pianciola, Luis Alfredo; Bergagna, Héctor Fabián Jesús; Lazzarini, Lorena Evelina; Mazzeo, Melina Leonor; Basualdo, Juan Angel

    2016-09-15

    Echinococcus granulosus sensu lato (E. granulosus sl) must be considered as a species complex, comprising Echinococcus granulosus sensu stricto (E. granulosus ss, genotypes G1-G3), Echinococcus equinus (G4), Echinococcus ortleppi (G5) and Echinococcus canadensis (G6-G10) although the species status of E. canadensis is still controversial. These genotypes closely match the intermediate hosts associated strains described in earlier times among which E. canadensis G6 corresponds to the camel strain. As there are no studies concerning the development of adult stages of the G6 genotype from non-camel origin, the aims of the present study were: to characterize for the first time the development of E. canadensis G6 in dogs experimentally infected with protoscoleces derived from goats, to describe the resultant adult morphology, to evaluate the growth of their rostellar hooks from larval to adult stages and to determine the prepatent period of the strobilar stage of E. canadensis G6 derived from goats. The development of the strobilar stage of E. canadensis G6 genotype of goat origin was examined by studying the growth (variation of the total worm length) and segmentation in experimentally infected dogs at 14, 25, 35 and 56days post infection. A morphological characterization of 35-day-old worms as well as of larval and adult rostellar hooks was also carried out by conventional optical microscopic observations and/or by scanning electron microscopy. The prepatent period of the strobilar stage was assessed by microscopic examination of faeces from 2 infected dogs. Our results were compared with published data from the camel and other strains. The roles of the host, genotype and species in morphological and developmental features as well as the taxonomic position of E. canadensis G6 were discussed. The prepatent period of E. canadensis G6 genotype of goat origin was determined as at least, 41days. The obtained results contribute to increase the knowledge about the biology

  7. Comparative Pathology of Hepatitis A Virus and Hepatitis E Virus Infection.

    Science.gov (United States)

    Cullen, John M; Lemon, Stanley M

    2018-04-30

    Hepatitis A virus (HAV) and hepatitis E virus (HEV) cause acute, self-limiting hepatic infections that are usually spread by the fecal-oral route in humans. Naturally occurring and experimental infections are possible in a variety of nonhuman primates and, in the case of HEV, a number of other species. Many advances in understanding the pathogenesis of these viruses have come from studies in experimental animals. In general, animals infected with these viruses recapitulate the histologic lesions seen in infected humans, but typically with less severe clinical and histopathological manifestations. This review describes the histopathologic changes associated with HAV and HEV infection in humans and experimental animals. Copyright © 2018 Cold Spring Harbor Laboratory Press; all rights reserved.

  8. Safety and efficacy of the bumped kinase inhibitor BKI-1553 in pregnant sheep experimentally infected with Neospora caninum tachyzoites

    Directory of Open Access Journals (Sweden)

    Roberto Sánchez-Sánchez

    2018-04-01

    Full Text Available Neospora caninum is one of the main causes of abortion in cattle, and recent studies have highlighted its relevance as an abortifacient in small ruminants. Vaccines or drugs for the control of neosporosis are lacking. Bumped kinase inhibitors (BKIs, which are ATP-competitive inhibitors of calcium dependent protein kinase 1 (CDPK1, were shown to be highly efficacious against several apicomplexan parasites in vitro and in laboratory animal models. We here present the pharmacokinetics, safety and efficacy of BKI-1553 in pregnant ewes and foetuses using a pregnant sheep model of N. caninum infection. BKI-1553 showed exposure in pregnant ewes with trough concentrations of approximately 4 μM, and of 1  μM in foetuses. Subcutaneous BKI-1553 administration increased rectal temperatures shortly after treatment, and resulted in dermal nodules triggering a slight monocytosis after repeated doses at short intervals. BKI-1553 treatment decreased fever in infected pregnant ewes already after two applications, resulted in a 37–50% reduction in foetal mortality, and modulated immune responses; IFNγ levels were increased early after infection and IgG levels were reduced subsequently. N. caninum was abundantly found in placental tissues; however, parasite detection in foetal brain tissue decreased from 94% in the infected/untreated group to 69–71% in the treated groups. In summary, BKI-1553 confers partial protection against abortion in a ruminant experimental model of N. caninum infection during pregnancy. In addition, reduced parasite detection, parasite load and lesions in foetal brains were observed. Keywords: Neospora caninum, Sheep, Pregnancy, Treatment, Protein kinase inhibitor, BKI-1553

  9. Distribution of sialic acid receptors and influenza A viruses of avian and swine origin and in experimentally infected pigs

    DEFF Research Database (Denmark)

    Trebbien, Ramona; Larsen, Lars Erik; Viuff, Birgitte M.

    2011-01-01

    Background: Pigs are considered susceptible to influenza A virus infections from different host origins because earlier studies have shown that they have receptors for both avian (sialic acid-alpha-2,3-terminal saccharides (SAalpha- 2,3)) and swine/human (SA-alpha-2,6) influenza viruses...... in the upper respiratory tract. Furthermore, experimental and natural infections in pigs have been reported with influenza A virus from avian and human sources. Methods: This study investigated the receptor distribution in the entire respiratory tract of pigs using specific lectins Maackia Amurensis (MAA) I...... and AIV virus was found, and this difference was in accordance with the distribution of the SA-alpha-2,6 and SA-alpha-2,3 receptor, respectively. The results indicated that the distribution of influenza A virus receptors in pigs are similar to that of humans and therefore challenge the theory that the pig...

  10. Dengue virus detection by using reverse transcription-polymerase chain reaction in saliva and progeny of experimentally infected Aedes albopictus from Brazil

    Directory of Open Access Journals (Sweden)

    Márcia Gonçalves de Castro

    2004-12-01

    Full Text Available Oral susceptibility and vertical transmission of dengue virus type 2 (DENV-2 in an Aedes albopictus sample from Rio de Janeiro was estimated. The infection (36.7% and transmission (83.3% rates for Ae. albopictus were higher than those of an Ae. aegypti colony used as control, 32.8 and 60%, respectively. Fourth instar larvae and females descendants of 48.5 and 39.1% of experimentally infected Ae. albopictus showed to harbor the virus. The oral susceptibility and the high capacity to assure vertical transmission exhibited by Ae. albopictus from Brazil reinforce that this species may play a role in the maintenance of the virus in nature and be a threat for dengue control in the country.

  11. Studies on the pathogenesis of Aleutian disease of mink. X. demonstration of immune complexes by the /sup 125/I-C 1 q binding test after experimental infection

    Energy Technology Data Exchange (ETDEWEB)

    Mueller-Peddinghaus, R [Kali-Chemie Pharma G.m.b.H., Hannover (Germany, F.R.). Abt. fuer Experimentelle Pathologie; Meyer zu Schwabedissen, H [Medizinische Hochschule Hannover (Germany, F.R.). Abt. fuer Klinische Immunologie und Bluttransfusionswesen; Kalden, J R [Erlangen-Nuernberg Univ., Erlangen (Germany, F.R.). Inst. und Poliklinik fuer Klinische Immunologie; Trautwein, G; Ueberschaer, S [Tieraerztliche Hochschule Hannover (Germany, F.R.). Inst. fuer Pathologie

    1980-01-01

    Aleutian disease (AD) of mink most closely resembles systemic lupus erythematosus (SLE) in man; both are immune complex disease. In experimental AD serum immune complexes are determined by the /sup 125/J-C 1 q-binding test using human C 1 q. Mink (n = 12) infected intraperitoneally with Aleutian disease virus (ADV), grown in fetal mink kidney cells, developed during the course of infection a mean of /sup 125/I-C 1 q serum binding equivalent to 3.62 +- 1.68 mg./ml. aggr. HGG. (aggregated human immunoglobulin). Sera of mink (n = 8) which were infected with ADV grown in L-cells showed a less marked /sup 125/I-C 1 q binding with a mean equivalent to 2.52 +- 1.43 mg./ml. aggr. HGG. In contrast control animals (n = 8) treated with non-ADV-infected mink epidermal fibroblasts or Eagle's minimal essential medium substituted with fetal calf serum only bound /sup 125/I-C 1 q equivalent to 1.02 +- 0.99 mg./ml. aggr. HGG. In mink infected with ADV propagated in fetal mink kidney cells a constant increase in the /sup 125/I-C 1 q serum binding occurred from the 4th to the 7th and 13th week after ADV infection. Mink which were infected with ADV propagated in mouse L-cells exhibited a different pattern of the /sup 125/I-C 1 q serum binding capacity with a sharp increase from the 4th to the 7th week, followed by a decline towards the 13th week post infection. The serum /sup 125/I-C 1 q binding capacity of all experimental animal groups exhibited at different times of the experiment a significant correlation with the presence of hypergammaglobulinaemia and raised ADV-antibody titers. From the data obtained it appears that the /sup 125/I-C 1 q binding test, utilizing human C 1 q, is a suitable method for the detection of circulating serum immune complexes in mink during the course of ADV-infection.

  12. Studies on Ancylostomiasis: 1.An Experimental Study on Hookworm Infection and Anemia

    International Nuclear Information System (INIS)

    Lee, Mun Ho; Kim, Dong Jip; Lee, Jang Kyu; Seo, Byong Sul; Lee, Soon Hyung

    1967-01-01

    In view of its prevalence in the Far East area, a more detailed knowledge on the hookworm infection is one of the very important medical problem. The present study was aimed to determine the infectivity of the artificially hatched ancylosotma duodenale larvae in man after its oral administration, evaluate the clinical symptomatology of such infection, determine the date of first appearance of ova in the stool, calculate the blood loss per worm per day, assess the relation-ships between the ova count, infectivity (worm load), blood loss and severity of anemia. An erythrokinetic study was also done to analyse the characteristics of hookworm anemia by means of 59 Fe and 51 Cr.

  13. Effects of Reproductive Hormones on Experimental Vaginal Candidiasis

    Science.gov (United States)

    Fidel, Paul L.; Cutright, Jessica; Steele, Chad

    2000-01-01

    Vulvovaginal candidiasis (VVC) is an opportunistic mucosal infection caused by Candida albicans that affects large numbers of otherwise healthy women of childbearing age. Acute episodes of VVC often occur during pregnancy and during the luteal phase of the menstrual cycle, when levels of progesterone and estrogen are elevated. Although estrogen-dependent experimental rodent models of C. albicans vaginal infection are used for many applications, the role of reproductive hormones and/or their limits in the acquisition of vaginal candidiasis remain unclear. This study examined the effects of estrogen and progesterone on several aspects of an experimental infection together with relative cell-mediated immune responses. Results showed that while decreasing estrogen concentrations eventually influenced infection-induced vaginal titers of C. albicans and rates of infection in inoculated animals, the experimental infection could not be achieved in mice treated with various concentrations of progesterone alone. Furthermore, progesterone had no effect on (i) the induction and persistence of the infection in the presence of estrogen, (ii) delayed-type hypersensitivity in primary-infected mice, or (iii) the partial protection from a secondary vaginal infection under pseudoestrus conditions. Other results with estrogen showed that a persistent infection could be established with a wide range of C. albicans inocula under supraphysiologic and near-physiologic (at estrus) concentrations of estrogen and that vaginal fungus titers or rates of infection were similar if pseudoestrus was initiated several days before or after inoculation. However, the pseudoestrus state had to be maintained for the infection to persist. Finally, estrogen was found to reduce the ability of vaginal epithelial cells to inhibit the growth of C. albicans. These results suggest that estrogen, but not progesterone, is an important factor in hormone-associated susceptibility to C. albicans vaginitis. PMID

  14. Novo processo para triagem de medicamentos na infecção experimental pelo Trypanosoma cruzi Proposal of a new process for screening of drugs in experimental infection with Trypanosoma cruzi

    Directory of Open Access Journals (Sweden)

    Rubens Campos

    1991-08-01

    Full Text Available É proposto processo para a triagem da capacidade terapêutica de medicamentos na infecção experimental pelo Trypanosoma cruzi. O método tem base no emprego de triatomíneos parasitados que se alimentam, decorridos períodos diferentes para haver compatibilização com níveis sangüíneos, em camundongos aos quais foi administrado o fármaco sob apreciação; assim, o tubo digestivo do hemíptero participará como estrutura propícia à avaliação. Em observação inicial, ocorreu utilização do benzonidazol, que se mostrou apenas parcialmente ativo, pelo menos de acordo com a maneira de execução do novo procedimento.We propose a screening process for detection of therapeutic activity of drugs against experimental infection with Trypanosoma cruzi. It is based on the use of infected tryatominae that are fed on mice which have received the study drug. Blood meals are made at different time schedule in order to adapt with serum drug levels. The digestive tube of the hemyptera will, thus, work as a suitable structure for examination. In a initial observation, benzonidazole was used, and was shown to be only partially active at least in the conditions of this new procedure.

  15. Experimental alveolitis in rats: microbiological, acute phase response and histometric characterization of delayed alveolar healing.

    Science.gov (United States)

    Rodrigues, Moacyr Tadeu Vicente; Cardoso, Camila Lopes; Carvalho, Paulo Sérgio Perri de; Cestari, Tânia Mary; Feres, Magda; Garlet, Gustavo Pompermaier; Ferreira, Osny

    2011-01-01

    The pathogenesis of alveolitis is not well known and therefore experimental situations that mimic some features of this disease should be developed. In this study, the evolution of the experimentally induced infection in rat sockets is characterized, which leads to clinical signs of suppurative alveolitis with remarkable wound healing disturbs. Non-infected (Group I) and experimentally infected sockets in Rattus novergicus (Group II) were histometrically evaluated regarding the kinetics of alveolar healing. In addition, the characterization of the present bacteria in inoculation material and the serum levels of C-reactive protein (CRP) were performed. The detected species were Capnocytophaga ochracea, Fusobacterium nucleatum ss nucleatum, Prevotella melaninogenica, Streptococcus anginosus, Treponema socranskii and Streptococcus sanguis. All experimentally infected rats developed suppurative alveolitis, showing higher levels of CRP in comparison to those non-infected ones. Furthermore, infected rats presented a significant delayed wound healing as measured by the histometric analysis (higher persistent polymorphonuclear infiltrate and lower density of newly formed bone). These findings indicate that rat sockets with experimentally induced infection produced higher levels of serum CRP, showing the potential of disseminated infection and a disturb in the alveolar repair process in an interesting experimental model for alveolitis studies.

  16. EXPERIMENTAL-INFECTION IN MICE WITH BACILLUS-LICHENIFORMIS

    DEFF Research Database (Denmark)

    Agerholm, J.S.; Jensen, H.E.; Jensen, N.E.

    1995-01-01

    The pathogenicity of Bacillus licheniformis was assessed in normal and immunodepressed BALB/c mice. The animals were challenged intravenously with 4 x 10(7) colony forming units of B, licheniformis (ATCC 14580) and both normal and immunodepressed mice were susceptible. However, the infection...... was more severe in the immunosuppressed animals. In normal mice, lesions were restricted to the liver and kidneys, while lesions also occurred in other organs of immunodepressed mice. By crossed immunoelectrophoresis it was shown that antigens of B. licheniformis are potent immunogens, and the bacteria...

  17. Congenital Toxoplasmosis in Chronically Infected and Subsequently Challenged Ewes.

    Science.gov (United States)

    Dos Santos, Thaís Rabelo; Faria, Gabriela da Silva Magalhães; Guerreiro, Bruna Martins; Dal Pietro, Nathalia Helena Pereira da Silva; Lopes, Welber Daniel Zanetti; da Silva, Helenara Machado; Garcia, João Luis; Luvizotto, Maria Cecília Rui; Bresciani, Katia Denise Saraiva; da Costa, Alvimar José

    2016-01-01

    This experiment studied congenital transmission in sheep experimentally infected with oocysts of Toxoplasma gondii and reinfected at one of three stages of pregnancy. Twenty ewes were experimentally infected with T. gondii strain ME49 (day 0). After the T. gondii infection became chronic (IFAT≤512), the ewes were allocated with rams for coverage. After the diagnosis of pregnancy, these ewes were allocated into four experimental groups (n = 5): I-reinfected with T. gondii on the 40th day of gestation (DG); II-reinfected on DG 80; III-reinfected on DG 120; and IV-saline solution on DG 120 (not reinfected). Five ewes (IFATewes produced lambs serologically positive for T. gondii. The results of the mouse bioassay, immunohistochemistry and PCR assays revealed the presence of T. gondii in all 20 sheep and their lambs. The congenital transmission of T. gondii was associated with fetal loss and abnormalities in persistently infected sheep and in ewes infected and subsequently reinfected by this protozoan. Therefore, congenital T. gondii infection was common when ewes were chronically infected prior to pregnancy, with or without reinfection during at various stages of gestation.

  18. Somatic cell count and milk neutrophil viability of dairy heifers with specific CXCR1 genotypes following experimental intramammary infection with Staphylococcus chromogenes originating from milk.

    Science.gov (United States)

    Verbeke, Joren; Piccart, Kristine; Piepers, Sofie; Van Poucke, Mario; Peelman, Luc; De Visscher, Anneleen; De Vliegher, Sarne

    2015-06-01

    Previous observational studies suggest an association between polymorphism c.980A>G in the CXCR1 gene, encoding the chemokine (C-X-C motif) receptor 1, and the innate immunity and infection status of the mammary gland. Mammary glands of eight Holstein heifers were experimentally infected with a Staphylococcus chromogenes isolate originating from a chronic intramammary infection (IMI) to study differences between CXCR1 genotypes c.980AG and c.980GG. Quarters from heifers with genotypes c.980AG and c.980GG developed subclinical mastitis but showed differences in the early response at 6-18 h post challenge. Bacterial count at 18 h post challenge tended to be higher in quarters from c.980AG heifers compared to c.980GG heifers. Somatic cell count (SCC) was higher at 6 h post challenge and tended to be higher at 9 h post challenge in c.980AG heifers compared to c.980GG heifers. Milk production decreased similarly. Milk neutrophils of c.980AG heifers showed more apoptosis at 9 h post challenge and tended to show more necrosis at 6, 9 and 12 h post challenge than c.980GG heifers. Differences were less pronounced in the later stage (>18 h) of infection. The results demonstrate that CXCR1 polymorphism can influence SCC and milk neutrophil viability following experimental IMI. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. An evaluation of the impact of aloe vera and licorice extracts on the course of experimental pigeon paramyxovirus type 1 infection in pigeons.

    Science.gov (United States)

    Dziewulska, D; Stenzel, T; Smialek, M; Tykalowski, B; Koncicki, A

    2018-02-01

    The progressive decrease in the efficiency of synthetic drugs has prompted research into phytogenic feed additives with potentially immunomodulatory and anti-infective properties. Complex diseases with a mixed etiology, including viral, pose a growing problem in domestic pigeons. The aim of this study was to determine the effectiveness of various doses of aloe vera and licorice extracts on the course of experimental PPMV-1 infection in pigeons. The experiment was performed on pigeons divided into 5 groups, including one control group and 4 experimental groups, which were orally administered aloe vera or licorice extracts at 300 or 500 mg/kg BW for 7 d after experimental inoculation with PPMV-1. On d 4, 7, and 14 after inoculation, cloacal swabs and samples of organs were collected from 4 birds in each group. The samples were analyzed to determine the copy number of PPMV-1 RNA by TaqMan qPCR. The results indicate that licorice and aloe vera extracts inhibited PPMV-1 replication by decreasing viral RNA copy numbers in the examined organs. The most inhibitory effect was observed in pigeons receiving aloe vera extract at 300 mg/kg BW, for which PPMV-1 RNA copy numbers were approximately 7-fold lower (brain), 9-fold lower (kidneys), and 14-fold lower (liver) than in the control group. The results of this study point to the potentially antiviral effects of aloe vera and licorice extracts in pigeons infected with PPMV-1. To the best of our knowledge, this is the first study to investigate the antiviral properties of aloe vera and licorice extracts in domestic pigeons. © The Author 2017. Published by Oxford University Press on behalf of Poultry Science Association.

  20. Immune gene expression in the spleen of chickens experimentally infected with Ascaridia galli

    DEFF Research Database (Denmark)

    Dalgaard, Tina S.; Skovgaard, Kerstin; Norup, Liselotte R.

    2015-01-01

    Ascaridia galli is a gastrointestinal nematode infecting chickens. Chickens kept in alternative rearing systems or at free-range experience increased risk for infection with resulting high prevalences. A. gall infection causes reduced weight gain, decreased egg production and in severe cases incr...

  1. Consecutive natural influenza a virus infections in sentinel mallards in the evident absence of subtype-specific hemagglutination inhibiting antibodies.

    Science.gov (United States)

    Globig, A; Fereidouni, S R; Harder, T C; Grund, C; Beer, M; Mettenleiter, T C; Starick, E

    2013-10-01

    Dabbling ducks, particularly Mallards (Anas platyrhynchos) have been frequently and consistently reported to play a pivotal role as a reservoir of low pathogenic avian influenza viruses (AIV). From October 2006 to November 2008, hand-raised Mallard ducks kept at a pond in an avifaunistically rich area of Southern Germany served as sentinel birds in the AIV surveillance programme in Germany. The pond was regularly visited by several species of dabbling ducks. A flock of sentinel birds, consisting of the same 16 individual birds during the whole study period, was regularly tested virologically and serologically for AIV infections. Swab samples were screened by RT-qPCR and, if positive, virus was isolated in embryonated chicken eggs. Serum samples were tested by the use of competitive ELISA and hemagglutinin inhibition (HI) assay. Sequences of full-length hemagglutinin (HA) and neuraminidase (NA) genes were phylogenetically analysed. Four episodes of infections with Eurasian-type AIV occurred in August (H6N8), October/November (H3N2, H2N3) 2007, in January (H3N2) and September (H3N8) 2008. The HA and NA genes of the H3N2 viruses of October 2007 and January 2008 were almost identical rendering the possibility of a re-introduction of that virus from the environment of the sentinel flock highly likely. The HA of the H3N8 virus of September 2008 belonged to a different cluster. As a correlate of the humoral immune response, titres of nucleocapsid protein-specific antibodies fluctuated in correlation with the course of AIV infection episodes. However, no specific systemic response of hemagglutination inhibiting antibodies could be demonstrated even if homologous viral antigens were used. Besides being useful as early indicators for the circulation of influenza viruses in a specific region, the sentinel ducks also contributed to gaining insights into the ecobiology of AIV infection in aquatic wild birds. © 2012 Blackwell Verlag GmbH.

  2. Female partner preferences enhance offspring ability to survive an infection.

    Science.gov (United States)

    Raveh, Shirley; Sutalo, Sanja; Thonhauser, Kerstin E; Thoß, Michaela; Hettyey, Attila; Winkelser, Friederike; Penn, Dustin J

    2014-01-23

    It is often suggested that mate choice enhances offspring immune resistance to infectious diseases. To test this hypothesis, we conducted a study with wild-derived house mice (Mus musculus musculus) in which females were experimentally mated either with their preferred or non-preferred male, and their offspring were infected with a mouse pathogen, Salmonella enterica (serovar Typhimurium). We found that offspring sired by preferred males were significantly more likely to survive the experimental infection compared to those sired by non-preferred males. We found no significant differences in the pathogen clearance or infection dynamics between the infected mice, suggesting that offspring from preferred males were better able to cope with infection and had improved tolerance rather than immune resistance. Our results provide the first direct experimental evidence within a single study that partner preferences enhance offspring resistance to infectious diseases.

  3. The dynamic influence of the DRB1*1101 allele on the resistance of sheep to experimental Teladorsagia circumcincta infection

    Directory of Open Access Journals (Sweden)

    Hassan Musa

    2011-03-01

    Full Text Available Abstract Suffolk sheep carrying the DRB1*1101 (previously referred to as-DRB1*0203 or G2 allele have been reported to show increased resistance to natural Teladorsagia circumcincta infection compared to non-carriers. The objective of this study was to compare the biochemical and physiological responses of DRB1*1101 carrier and non-carrier twin lambs to an experimental infection with 3 × 104 L3 Teladorsagia circumcincta. The variables studied included worm burden, faecal egg count, abomasal mast cells, IgA, IgE, IgG1 plus IgG2 and haematological parameters at 0, 3, 7, 21 and 35 days post infection (dpi, and duodenal smooth muscle contractility at 0 and 35 dpi. DRB1*1101 carrier lambs had significantly lower worm burden, higher mast cell and plasma platelet counts than the DRB1*1101 non-carriers (P DRB1*1101 non-carrier lambs had a significantly higher plasma lymphocyte count, and produced greater duodenal contractile force relative to the carrier lambs (P DRB1*1101 is acquired rather than innate, depends on worm expulsion rather than fecundity and is dependent on mucosal mast cell proliferation, platelet activation, and IgA and IgE antibody responses.

  4. Cellular composition of granulomatous lesions in gut-associated lymphoid tissues of goats during the first year after experimental infection with Mycobacterium avium subsp. paratuberculosis.

    Science.gov (United States)

    Krüger, C; Köhler, H; Liebler-Tenorio, E M

    2015-01-15

    Mycobacterium avium subsp. paratuberculosis (MAP) causes lesions in naturally and experimentally infected ruminants which greatly differ in severity, cellular composition and number of mycobacteria. Morphologically distinct lesions are already found during the clinically inapparent phase of infection. The complex local host response and number of MAP were characterized at the initial sites of lesions, organized gut-associated lymphoid tissue, in experimentally infected goats. Tissues were collected at 3, 6, 9 and 12 month post-inoculation (mpi) from goat kids that had orally received 10 times 10mg of bacterial wet mass of MAP (JII-1961). The cellular composition of lesions in Peyer's patches in the jejunum and next to the ileocecal valve was evaluated in 21 MAP-inoculated goats, where lesions were compared with unaltered tissue of six control goats. CD68+, CD4+, CD8+, γδ T lymphocytes, B lymphocytes and plasma cells, MHC class II+ and CD25+ cells were demonstrated by immunohistochemistry in serial cryostat sections. At 3 mpi, extensive granulomatous infiltrates predominated, consisting of numerous epitheloid cells admixed with many CD4 and γδ T lymphocytes. Only single MAP were detected. This indicates a strong cellular immune reaction able to control MAP infection. γδ T lymphocytes were markedly increased in this type of lesion which may reflect their important role early in the pathogenesis of paratuberculosis. At 9 and 12 mpi, divergent lesions were observed which may reflect different outcomes of host-pathogen interactions. In five goats, minimal granulomatous lesions were surrounded by extensive lymphoplasmacytic infiltrates and no MAP were detected by immunohistochemistry. This was interpreted as effective host response that was able to eliminate MAP locally. In three goats, decreased numbers of lymphocytes, but extensive granulomatous infiltrates with numerous epitheloid cells containing increased numbers of mycobacteria were seen. This shift of the

  5. Infection studies with two highly pathogenic avian influenza strains (Vietnamese and Indonesian) in Pekin ducks (Anas platyrhynchos), with particular reference to clinical disease, tissue tropism and viral shedding.

    Science.gov (United States)

    Bingham, John; Green, Diane J; Lowther, Sue; Klippel, Jessica; Burggraaf, Simon; Anderson, Danielle E; Wibawa, Hendra; Hoa, Dong Manh; Long, Ngo Thanh; Vu, Pham Phong; Middleton, Deborah J; Daniels, Peter W

    2009-08-01

    Pekin ducks were infected by the mucosal route (oral, nasal, ocular) with one of two strains of Eurasian lineage H5N1 highly pathogenic avian influenza virus: A/Muscovy duck/Vietnam/453/2004 and A/duck/Indramayu/BBVW/109/2006 (from Indonesia). Ducks were killed humanely on days 1, 2, 3, 5 and 7 after challenge, or whenever morbidity was severe enough to justify euthanasia. Morbidity was recorded by observation of clinical signs and cloacal temperatures; the disease was characterized by histopathology; tissue tropism was studied by immunohistochemistry and virus titration on tissue samples; and viral shedding patterns were determined by virus isolation and titration of oral and cloacal swabs. The Vietnamese strain caused severe morbidity with fever and depression; the Indonesian strain caused only transient fever. Both viruses had a predilection for a similar range of tissue types, but the quantity of tissue antigen and tissue virus titres were considerably higher with the Vietnamese strain. The Vietnamese strain caused severe myocarditis and skeletal myositis; both strains caused non-suppurative encephalitis and a range of other inflammatory reactions of varying severity. The principal epithelial tissue infected was that of the air sacs, but antigen was not abundant. Epithelium of the turbinates, trachea and bronchi had only rare infection with virus. Virus was shed from both the oral and cloacal routes; it was first detected 24 h after challenge and persisted until day 5 after challenge. The higher prevalence of virus from swabs from ducks infected with the Vietnamese strain indicates that this strain may be more adapted to ducks than the Indonesia strain.

  6. A comparative evaluation of feathers, oropharyngeal swabs, and cloacal swabs for the detection of H5N1 highly pathogenic avian influenza virus infection in experimentally infected chickens and ducks.

    Science.gov (United States)

    Nuradji, Harimurti; Bingham, John; Lowther, Sue; Wibawa, Hendra; Colling, Axel; Long, Ngo Thanh; Meers, Joanne

    2015-11-01

    Oropharyngeal and cloacal swabs have been widely used for the detection of H5N1 highly pathogenic avian Influenza A virus (HPAI virus) in birds. Previous studies have shown that the feather calamus is a site of H5N1 virus replication and therefore has potential for diagnosis of avian influenza. However, studies characterizing the value of feathers for this purpose are not available, to our knowledge; herein we present a study investigating feathers for detection of H5N1 virus. Ducks and chickens were experimentally infected with H5N1 HPAI virus belonging to 1 of 3 clades (Indonesian clades 2.1.1 and 2.1.3, Vietnamese clade 1). Different types of feathers and oropharyngeal and cloacal swab samples were compared by virus isolation. In chickens, virus was detected from all sample types: oral and cloacal swabs, and immature pectorosternal, flight, and tail feathers. During clinical disease, the viral titers were higher in feathers than swabs. In ducks, the proportion of virus-positive samples was variable depending on viral strain and time from challenge; cloacal swabs and mature pectorosternal feathers were clearly inferior to oral swabs and immature pectorosternal, tail, and flight feathers. In ducks infected with Indonesian strains, in which most birds did not develop clinical signs, all sampling methods gave intermittent positive results; 3-23% of immature pectorosternal feathers were positive during the acute infection period; oropharyngeal swabs had slightly higher positivity during early infection, while feathers performed better during late infection. Our results indicate that immature feathers are an alternative sample for the diagnosis of HPAI in chickens and ducks. © 2015 The Author(s).

  7. Putative biomarkers for evaluating antibiotic treatment: an experimental model of porcine Actinobacillus pleuropneumoniae infection

    DEFF Research Database (Denmark)

    Lauritzen, B.; Lykkesfeldt, J.; Skaanild, M.T.

    2003-01-01

    Biomarkers of infection were screened for their possible role as evaluators of antibiotic treatment in an aerosol infection model of porcine pneumonia caused by Actinobacillus pleuropneumoniae (Ap). Following infection of 12 pigs, clinical signs of pneumonia developed within 20 h, whereafter...... antibiotic treatment of acute Ap-infection ill pigs. The present model provides a valuable tool in the evaluation of antibiotic treatments, offering the advantage of clinical and pathological examinations combined with the use of biochemical infection markers....... recovered clinically within 24h after treatment, whereas tiamulin-treated animals remained clinically ill until the end of the study, 48 h after treatment. A similar Picture was seen for the biomarkers of infection. During the infection period, plasma C-reactive protein (CRP), interleukin-6 and haptoglobin...

  8. Nanoparticle-mediated drug delivery to treat infections in the female reproductive tract: evaluation of experimental systems and the potential for mathematical modeling.

    Science.gov (United States)

    Sims, Lee B; Frieboes, Hermann B; Steinbach-Rankins, Jill M

    2018-01-01

    A variety of drug-delivery platforms have been employed to deliver therapeutic agents across cervicovaginal mucus (CVM) and the vaginal mucosa, offering the capability to increase the longevity and retention of active agents to treat infections of the female reproductive tract (FRT). Nanoparticles (NPs) have been shown to improve retention, diffusion, and cell-specific targeting via specific surface modifications, relative to other delivery platforms. In particular, polymeric NPs represent a promising option that has shown improved distribution through the CVM. These NPs are typically fabricated from nontoxic, non-inflammatory, US Food and Drug Administration-approved polymers that improve biocompatibility. This review summarizes recent experimental studies that have evaluated NP transport in the FRT, and highlights research areas that more thoroughly and efficiently inform polymeric NP design, including mathematical modeling. An overview of the in vitro, ex vivo, and in vivo NP studies conducted to date - whereby transport parameters are determined, extrapolated, and validated - is presented first. The impact of different NP design features on transport through the FRT is summarized, and gaps that exist due to the limitations of iterative experimentation alone are identified. The potential of mathematical modeling to complement the characterization and evaluation of diffusion and transport of delivery vehicles and active agents through the CVM and mucosa is discussed. Lastly, potential advancements combining experimental and mathematical knowledge are suggested to inform next-generation NP designs, such that infections in the FRT may be more effectively treated.

  9. Early and Late Pathogenic Events of Newborn Mice Encephalitis Experimentally Induced by Itacaiunas and Curionópolis Bracorhabdoviruses Infection

    Science.gov (United States)

    Diniz, José Antonio Picanço; dos Santos, Zaire Alves; Braga, Marcio Augusto Galvão; Dias, Ádila Liliane Barros; da Silva, Daisy Elaine Andrade; Medeiros, Daniele Barbosa de Almeida; Barros, Vera Lucia Reis de Souza; Chiang, Jannifer Oliveira; Zoghbi, Kendra Eyllen de Freitas; Quaresma, Juarez Antônio Simões; Takiya, Christina Maeda; Moura Neto, Vivaldo; de Souza, Wanderley; Vasconcelos, Pedro Fernando da Costa; Diniz, Cristovam Wanderley Picanço

    2008-01-01

    In previous reports we proposed a new genus for Rhabdoviridae and described neurotropic preference and gross neuropathology in newborn albino Swiss mice after Curionopolis and Itacaiunas infections. In the present report a time-course study of experimental encephalitis induced by Itacaiunas and Curionopolis virus was conducted both in vivo and in vitro to investigate cellular targets and the sequence of neuroinvasion. We also investigate, after intranasal inoculation, clinical signs, histopathology and apoptosis in correlation with viral immunolabeling at different time points. Curionopolis and Itacaiunas viral antigens were first detected in the parenchyma of olfactory pathways at 2 and 3 days post-inoculation (dpi) and the first clinical signs were observed at 4 and 8 dpi, respectively. After Curionopolis infection, the mortality rate was 100% between 5 and 6 dpi, and 35% between 8 and 15 dpi after Itacaiunas infection. We identified CNS mice cell types both in vivo and in vitro and the temporal sequence of neuroanatomical olfactory areas infected by Itacaiunas and Curionopolis virus. Distinct virulences were reflected in the neuropathological changes including TUNEL immunolabeling and cytopathic effects, more intense and precocious after intracerebral or in vitro inoculations of Curionopolis than after Itacaiunas virus. In vitro studies revealed neuronal but not astrocyte or microglial cytopathic effects at 2 dpi, with monolayer destruction occurring at 5 and 7 dpi with Curionopolis and Itacaiunas virus, respectively. Ultrastructural changes included virus budding associated with interstitial and perivascular edema, endothelial hypertrophy, a reduced and/or collapsed small vessel luminal area, thickening of the capillary basement membrane, and presence of phagocytosed apoptotic bodies. Glial cells with viral budding similar to oligodendrocytes were infected with Itacaiunas virus but not with Curionopolis virus. Thus, Curionopolis and Itacaiunas viruses share

  10. Early and late pathogenic events of newborn mice encephalitis experimentally induced by itacaiunas and curionópolis bracorhabdoviruses infection.

    Directory of Open Access Journals (Sweden)

    José Antonio Picanço Diniz

    Full Text Available In previous reports we proposed a new genus for Rhabdoviridae and described neurotropic preference and gross neuropathology in newborn albino Swiss mice after Curionopolis and Itacaiunas infections. In the present report a time-course study of experimental encephalitis induced by Itacaiunas and Curionopolis virus was conducted both in vivo and in vitro to investigate cellular targets and the sequence of neuroinvasion. We also investigate, after intranasal inoculation, clinical signs, histopathology and apoptosis in correlation with viral immunolabeling at different time points. Curionopolis and Itacaiunas viral antigens were first detected in the parenchyma of olfactory pathways at 2 and 3 days post-inoculation (dpi and the first clinical signs were observed at 4 and 8 dpi, respectively. After Curionopolis infection, the mortality rate was 100% between 5 and 6 dpi, and 35% between 8 and 15 dpi after Itacaiunas infection. We identified CNS mice cell types both in vivo and in vitro and the temporal sequence of neuroanatomical olfactory areas infected by Itacaiunas and Curionopolis virus. Distinct virulences were reflected in the neuropathological changes including TUNEL immunolabeling and cytopathic effects, more intense and precocious after intracerebral or in vitro inoculations of Curionopolis than after Itacaiunas virus. In vitro studies revealed neuronal but not astrocyte or microglial cytopathic effects at 2 dpi, with monolayer destruction occurring at 5 and 7 dpi with Curionopolis and Itacaiunas virus, respectively. Ultrastructural changes included virus budding associated with interstitial and perivascular edema, endothelial hypertrophy, a reduced and/or collapsed small vessel luminal area, thickening of the capillary basement membrane, and presence of phagocytosed apoptotic bodies. Glial cells with viral budding similar to oligodendrocytes were infected with Itacaiunas virus but not with Curionopolis virus. Thus, Curionopolis and

  11. Immune responses of a chimaeric protein vaccine containing Mycoplasma hyopneumoniae antigens and LTB against experimental M. hyopneumoniae infection in pigs.

    Science.gov (United States)

    Marchioro, Silvana B; Sácristan, Rubén Del Pozo; Michiels, Annelies; Haesebrouck, Freddy; Conceição, Fabricio R; Dellagostin, Odir A; Maes, Dominiek

    2014-08-06

    A recombinant chimaeric protein containing three Mycoplasma hyopneumoniae antigens (C-terminal portion of P97, heat shock protein P42, and NrdF) fused to an adjuvant, the B subunit of heat-labile enterotoxin of Escherichia coli (LTB), was used to immunize pigs against enzootic pneumonia. The systemic and local immune responses, as well as the efficacy of the chimaeric protein in inducing protection against experimental M. hyopneumoniae infection were evaluated. In total, 60 male piglets, purchased from a M. hyopneumoniae-free herd, at 4 weeks of age were randomly allocated to six different experimental groups of 10 animals each: recombinant chimaeric protein by intramuscular (IM) (1) or intranasal (IN) (2) administration, commercial bacterin by IM administration (3), and the adjuvant LTB by IM (4, control group A) or IN (5, control group B) administration. All groups were immunized at 24 and 38 days of age and challenged at 52 days of age. The sixth group that was not challenged was used as the negative control (IN [n=5] or IM [n=5] administration of the LTB adjuvant). Compared with the non-challenged group, administration of the chimaeric protein induced significant (Phyopneumoniae infection in pigs. This lack of effectiveness points towards the need for further studies to improve the efficacy of this subunit-based vaccine approach. Copyright © 2014 Elsevier Ltd. All rights reserved.

  12. Lack of prion transmission by sexual or parental routes in experimentally infected hamsters.

    Science.gov (United States)

    Morales, Rodrigo; Pritzkow, Sandra; Hu, Ping Ping; Duran-Aniotz, Claudia; Soto, Claudio

    2013-01-01

    Prion diseases are a group of neurodegenerative disorders affecting humans as well as captive and wild animals. The mechanisms and routes governing the natural spread of prions are not completely understood and several hypotheses have been proposed. In this study, we analyzed the effect of gender in prion incubation period, as well as the possibility of prion transmission by sexual and parental contact using 263K infected hamsters as a model. Our results show that males have significantly longer incubation periods compared with females when exposed to the same quantity of infectious material. Importantly, no evidence of sexual or parental prion transmission was found, even 500 d after sexual contact or birth, respectively. Western blotting and PMCA were unable to detect sub-clinical levels of PrP(Sc) in experimental subjects, suggesting a complete absence of prion transmission by these routes. Our results show that sexual and parental transmission of prions does not occur in this model. It remains to be studied whether this conclusion is valid also for other prion strains and species.

  13. Experimental Infection of the Mayan Cichlid Cichlasoma urophthalmus with the Oomycete Aphanomyces invadans.

    Science.gov (United States)

    Aguirre-Ayala, Daniel; Vidal-Martínez, Víctor Manuel

    2015-08-01

    This study aimed to determine the susceptibility of the Mayan cichlid Cichlasoma urophthalmus to infection with the fungus Aphanomyces invadans (also known as epizootic ulcerative syndrome [EUS]). A total of 27 C. urophthalmus were exposed to the original A. Invadans 2006/86/EC strain by intramuscularly injecting the fish with 25,000 zoospores/ml or exposing the fish to a suspension of 25,000 zoospores/ml in 6-L aquaria for 30 days. To assess the infectious capacity of A. invadans, 3 golden barbs (Puntius semifasciolatus) were infected intramuscularly with 200,000 zoospores/ml. A second experiment using 100 C. urophthalmus was performed for 60 days with 50 fish in each treatment group. A polymerase chain reaction (PCR)-based diagnostic method was used; muscle and gills were the target tissues. In the first experiment, none of the exposed C. urophthalmus developed skin lesions related to A. invadans infection. However, PCR analysis revealed that infection had occurred. For the intramuscular treatment, there were significant differences between the controls and the muscle samples (Fisher's exact test; P 0.05). All golden barbs became infected, as indicated by PCR, and developed skin lesions typical of A. invadans infection. We concluded that C. urophthalmus was infected with A. invadans but was an asymptomatic carrier because skin lesions did not develop. In the second experiment, all fish were negative, suggesting that the fish had cleared the infection by the end of the experiment.

  14. Differential Disease Susceptibilities in Experimentally Reptarenavirus-Infected Boa Constrictors and Ball Pythons

    Science.gov (United States)

    Sanchez-Migallon Guzman, David; Garcia, Valentina E.; Layton, Marylee L.; Hoon-Hanks, Laura L.; Boback, Scott M.; Keel, M. Kevin; Drazenovich, Tracy

    2017-01-01

    ABSTRACT Inclusion body disease (IBD) is an infectious disease originally described in captive snakes. It has traditionally been diagnosed by the presence of large eosinophilic cytoplasmic inclusions and is associated with neurological, gastrointestinal, and lymphoproliferative disorders. Previously, we identified and established a culture system for a novel lineage of arenaviruses isolated from boa constrictors diagnosed with IBD. Although ample circumstantial evidence suggested that these viruses, now known as reptarenaviruses, cause IBD, there has been no formal demonstration of disease causality since their discovery. We therefore conducted a long-term challenge experiment to test the hypothesis that reptarenaviruses cause IBD. We infected boa constrictors and ball pythons by cardiac injection of purified virus. We monitored the progression of viral growth in tissues, blood, and environmental samples. Infection produced dramatically different disease outcomes in snakes of the two species. Ball pythons infected with Golden Gate virus (GoGV) and with another reptarenavirus displayed severe neurological signs within 2 months, and viral replication was detected only in central nervous system tissues. In contrast, GoGV-infected boa constrictors remained free of clinical signs for 2 years, despite high viral loads and the accumulation of large intracellular inclusions in multiple tissues, including the brain. Inflammation was associated with infection in ball pythons but not in boa constrictors. Thus, reptarenavirus infection produces inclusions and inclusion body disease, although inclusions per se are neither necessarily associated with nor required for disease. Although the natural distribution of reptarenaviruses has yet to be described, the different outcomes of infection may reflect differences in geographical origin. IMPORTANCE New DNA sequencing technologies have made it easier than ever to identify the sequences of microorganisms in diseased tissues, i

  15. Revisiting host preference in the Mycobacterium tuberculosis complex: experimental infection shows M. tuberculosis H37Rv to be avirulent in cattle.

    Directory of Open Access Journals (Sweden)

    Adam O Whelan

    Full Text Available Experiments in the late 19th century sought to define the host specificity of the causative agents of tuberculosis in mammals. Mycobacterium tuberculosis, the human tubercle bacillus, was independently shown by Smith, Koch, and von Behring to be avirulent in cattle. This finding was erroneously used by Koch to argue the converse, namely that Mycobacterium bovis, the agent of bovine tuberculosis, was avirulent for man, a view that was subsequently discredited. However, reports in the literature of M. tuberculosis isolation from cattle with tuberculoid lesions suggests that the virulence of M. tuberculosis for cattle needs to be readdressed. We used an experimental bovine infection model to test the virulence of well-characterized strains of M. tuberculosis and M. bovis in cattle, choosing the genome-sequenced strains M. tuberculosis H37Rv and M. bovis 2122/97. Cattle were infected with approximately 10(6 CFU of M. tuberculosis H37Rv or M. bovis 2122/97, and sacrificed 17 weeks post-infection. IFN-gamma and tuberculin skin tests indicated that both M. bovis 2122 and M. tuberculosis H37Rv were equally infective and triggered strong cell-mediated immune responses, albeit with some indication of differential antigen-specific responses. Postmortem examination revealed that while M. bovis 2122/97-infected animals all showed clear pathology indicative of bovine tuberculosis, the M. tuberculosis-infected animals showed no pathology. Culturing of infected tissues revealed that M. tuberculosis was able to persist in the majority of animals, albeit at relatively low bacillary loads. In revisiting the early work on host preference across the M. tuberculosis complex, we have shown M. tuberculosis H37Rv is avirulent for cattle, and propose that the immune status of the animal, or genotype of the infecting bacillus, may have significant bearing on the virulence of a strain for cattle. This work will serve as a baseline for future studies into the genetic basis

  16. Experimental single and trickle infections of cattle with Taenia saginata: Studies of immunodiagnosis

    DEFF Research Database (Denmark)

    Bøgh, H.O.; Grønvold, J.; Maeda, G.E.

    1996-01-01

    Two groups of 12 calves were given either a single infection dose of 30,000 Taenia saginata eggs (group A) or trickle infected with 12 x 2500 T saginata eggs (group B). The calves were killed 16, 22 or 54 weeks after infection and the numbers of viable and dead parasites were counted by slicing...

  17. Feline immunodeficiency virus (FIV) infection in the cat as a model for HIV infection in man: FIV induced impairment of immune function.

    NARCIS (Netherlands)

    C.H.J. Siebelink (Kees); I-H. Chu (I-Hai); G.F. Rimmelzwaan (Guus); K. Weijer (Kees); R. van Herwijnen (Rob); P. Knell (Peter); H.F. Egberink (Herman); M.L. Bosch (Marnix); A.D.M.E. Osterhaus (Albert)

    1990-01-01

    textabstractTo assess the value of feline immunodeficiency virus (FIV) infection as a model for human immunodeficiency virus (HIV) infection in man, we studied the impairment of certain immunological functions following natural or experimental FIV infection. Proliferative responses of peripheral

  18. Experimental infection with epizootic haematopoietic necrosis virus (EHNV of rainbow trout (Oncorhynchus mykiss Walbaum and European perch (Perca fluviatilis L.

    Directory of Open Access Journals (Sweden)

    Borzym Ewa

    2015-12-01

    Full Text Available The aim of this study was the determination of the susceptibility of Polish farmed redfin perch (Perca fluviatilis L. and rainbow trout (Oncorhynchus mykiss Walbaum to experimental infection with haematopoietic necrosis virus (EHNV. A bath challenge model was tested at two temperature ranges: 13-15°C and 20-22°C. After 7 d, the first clinical signs and mortality were observed in fish kept at these temperatures. Significantly more mortality cases were reported in the redfin perch population, reaching a maximum of 24% compared with 12% in the rainbow trout group at 20-22°C. EHNV was reisolated from redfin perch and rainbow trout tissue in cell culture and the infection was confirmed by a molecular method and histopathology during the duration of the experiment. This study revealed that fish from Polish farms can be susceptible to EHNV even at lower temperatures.

  19. Studies on experimental infection of rabbits with irradiated metacercariae of Fasciola giganticas Cobbold, 1885

    International Nuclear Information System (INIS)

    Subramanian, G.; Srivastava, V.K.; Verma, J.C.

    1976-01-01

    Worm burden, gross pathology and serological response of rabbits infected with gamma irradiated metacercariae of Fasciola gigantica has been studied with a view to prepare a vaccine against the pathogen. Infection with metacercariae irradiated at 2 or 3 kr caused reduced worm burden and gross pathology and produced antibody titres comparable to the titres in rabbits infected with normal cysts. Infection with metacercariae irradiated at 4 kr resulted in total absence of worm burden and caused no rise of antibody titre in the sera of rabbits. In every case after infection, worm burden was progressively eliminated over long duration. The pathogenicity was comparatively severe in rabbits infected with normal cysts. (M.G.B.)

  20. Field and experimental symptomless infections support wandering donkeys as healthy carriers of Trypanosoma vivax in the Brazilian Semiarid, a region of outbreaks of high mortality in cattle and sheep.

    Science.gov (United States)

    Rodrigues, Carla M F; Batista, Jael S; Lima, Joseney M; Freitas, Francisco J C; Barros, Isabella O; Garcia, Herakles A; Rodrigues, Adriana C; Camargo, Erney P; Teixeira, Marta M G

    2015-10-28

    The Brazilian Semiarid is the home of the largest herd of donkeys in South America and of outbreaks of Trypanosoma vivax infection of high mortality in dairy cattle and sheep. For a comprehensive understanding of the underlying mechanisms of these outbreaks and epidemiological role of donkeys, we surveyed for T. vivax in wandering donkeys and follow the experimental infection of donkeys and sheep with a highly virulent isolate from the Semiarid. Blood samples from 180 randomly selected wandering donkeys from the Brazilian Semiarid region were employed for PCV and parasitemia assessments and tested using the T. vivax-specific TviCATL-PCR assay. PCR-amplifed Cathepsin L (CATL) sequences were employed for genotyping and phylogenetic analysis. Four wandering donkeys were experimentally infected with a T. vivax isolate obtained during an outbreak of high mortality in the Semiarid; the control group consisted of two non-inoculated donkeys. We detected T. vivax in 30 of 180 wandering donkeys (16.6 %) using TviCATL-PCR. The prevalence was higher during the dry (15.5 %) than the wet season (1.1 %) and more females (23.1 %) than males (8.9 %) were infected. All the PCR-positive donkeys lacked patent parasitemia and showed normal values of body condition score (BCS) and packed cell volume (PCV). To evaluate the probable tolerance of donkeys to T. vivax, we inoculated five donkeys with a highly virulent isolate (TviBrRp) from the Semiarid. All inoculated donkeys became PCR-positive, but their parasitemia was always subpatent. A control goat inoculated with TviBrRp showed increasing parasitemia concurrently with fever, declining PCV, tachycardia, mucous membrane pallor, enlarged lymph nodes and anorexia. None of these signs were observed in donkeys. However, T. vivax from wandering donkeys shared identical or highly similar genotypes (identified by Cathepsin L sequences) with isolates from cattle and sheep outbreaks of acute disease in the Semiarid. This is the first

  1. Effects of experimental Trypanosoma congolense infection on sperm morphology in Yankasa rams

    Directory of Open Access Journals (Sweden)

    Oluyinka O. Okubanjo

    2015-10-01

    Full Text Available The objective of the study was to determine the effect of T. congolense on the sperm morphology of Yankasa rams (YKR. Nine YKR aged 24-30 months-old were assigned into two groups of 6 infected and 3 uninfected control and were monitored for 7 weeks. The infected group of YKR was each inoculated with 1 x 106 T. congolense through the jugular vein, while the control group remained uninfected. The entire infected group developed trypanosomosis post infection (pi characterized by sperm morphological abnormalities in the semen. There were significant (P<0.001 increases in the mean percentage of acrosomal, head, middle piece and tail abnormalities. Proximal and distal droplets as well detached heads were also significantly (P<0.001 increased post infection (pi. Acrosomal abnormalities, distal droplet and tail abnormalities increased from week 1 pi till the end of the study, while head abnormalities and detached heads increased from week 2 pi. Middle piece abnormalities and proximal droplets increased from week 3 and 4 pi till the end of the study respectively. The high incidence of morphological defects caused by T. congolense is capable of causing infertility from the first week pi thereby making the rams unfit for breeding at the end of the study.

  2. EXPERIMENTAL INFECTION WITH Toxocara cati IN PIGS: MIGRATORY PATTERN AND PATHOLOGICAL RESPONSE IN EARLY PHASE

    Directory of Open Access Journals (Sweden)

    Irma Estela Sommerfelt

    2014-07-01

    Full Text Available Experimental inoculations of approximately 100,000 infective Toxocara cati larval eggs were done in twelve pigs. The T. cati eggs used for inoculation were collected from cat's feces. Another group of three pigs served as an uninfected control. Groups of infected pigs were euthanized at seven, 14, 21, and 28 days post-inoculation (dpi. Tissue samples were taken for digestion and histopathology changes in early phase. The number of larvae recovered from the lungs peaked at seven and 14 dpi and were also present at 21, and 28 dpi. Larvae of T. cati were present in the lymph nodes of the small and large intestine at seven, 14, and 28 dpi and at seven, 14, 21, and 28 dpi respectively. In other studied tissues, no larvae or less than one larva per gram was detected. The pathological response observed in the liver and lungs at seven and 14 dpi, showed white spots on the liver surface and areas of consolidation were observed in the lungs. The lungs showed an inflammatory reaction with larvae in center at 28 dpi. In the liver we observed periportal and perilobular hepatitis. The lymph nodes of the intestines displayed eosinophil lymphadenitis with reactive centers containing parasitic forms in some of them. The granulomatous reaction was not observed in any tissues. The role of the other examined tissues had less significance. The relevance of this parasite as an etiological agent that leads to disease in paratenic hosts is evident.

  3. Virological and clinico-pathological features of orf virus infection in experimentally infected rabbits and mice.

    Science.gov (United States)

    Cargnelutti, J F; Masuda, E K; Martins, M; Diel, D G; Rock, D L; Weiblen, R; Flores, E F

    2011-01-01

    Many aspects of the biology of orf virus (ORFV) infection remain poorly understood and attempts to establish animal models have yielded conflicting and non-reproducible results. We herein describe the characterization of ORFV infection and disease in rabbits and mice. A protocol of intradermal inoculation was employed to inoculate 10(8.5)TCID₅₀/mL of ORFV strain IA-82 in the skin of ears, of the back and labial commissures. All inoculated rabbits presented a clinical course characterized by erythema, macules, papules/vesicles or pustules that eventually dried originating scabs. Local signs started around days 3 and 4 post-inoculation (pi) and lasted 3-10 days. Virus was recovered from lesions between days 2 and 14pi. Histological examination of lesions revealed focal proliferative dermatitis with ballooning degeneration and eosinophilic intracytoplasmic inclusion bodies in keratinocytes, histological hallmarks of contagious ecthyma in sheep. A similar, albeit milder clinical course occurred in 5/10 inoculated mice; virus was recovered from lesions from three animals. Inoculated lambs - used as controls - developed severe lesions of contagious ecthyma. VN tests performed at day 28pi failed to detect neutralizing antibodies in all inoculated animals. In contrast, convalescent rabbit sera were positive by ELISA at dilutions from 100 to 400. These results show that rabbits are susceptible to ORFV infection and thus may be used to study selected aspects of ORFV biology. Copyright © 2010 Elsevier Ltd. All rights reserved.

  4. Experimental infection with highly pathogenic H5N8 avian influenza viruses in the Mandarin duck (Aix galericulata) and domestic pigeon (Columba livia domestica).

    Science.gov (United States)

    Kwon, Jung-Hoon; Noh, Yun Kyung; Lee, Dong-Hun; Yuk, Seong-Su; Erdene-Ochir, Tseren-Ochir; Noh, Jin-Yong; Hong, Woo-Tack; Jeong, Jei-Hyun; Jeong, Sol; Gwon, Gyeong-Bin; Song, Chang-Seon; Nahm, Sang-Soep

    2017-05-01

    Wild birds play a major role in the evolution, maintenance, and dissemination of highly pathogenic avian influenza viruses (HPAIV). Sub-clinical infection with HPAI in resident wild birds could be a source of dissemination of HPAIV and continuous outbreaks. In this study, the pathogenicity and infectivity of two strains of H5N8 clade 2.3.4.4 virus were evaluated in the Mandarin duck (Aix galericulata) and domestic pigeon (Columba livia domestica). None of the birds experimentally infected with H5N8 viruses showed clinical signs or mortality. The H5N8 viruses efficiently replicated in the virus-inoculated Mandarin ducks and transmitted to co-housed Mandarin ducks. Although relatively high levels of viral shedding were noted in pigeons, viral shedding was not detected in some of the pigeons and the shedding period was relatively short. Furthermore, the infection was not transmitted to co-housed pigeons. Immunohistochemical examination revealed the presence of HPAIV in multiple organs of the infected birds. Histopathological evaluation showed the presence of inflammatory responses primarily in HPAIV-positive organs. Our results indicate that Mandarin ducks and pigeons can be infected with H5N8 HPAIV without exhibiting clinical signs; thus, they may be potential healthy reservoirs of the H5N8 HPAIV. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. Activity and milk compositional changes following experimentally induced Streptococcus uberis bovine mastitis.

    Science.gov (United States)

    Kester, H J; Sorter, D E; Hogan, J S

    2015-02-01

    Milk constituents and physical activity of cows experimentally infected with Streptococcus uberis mastitis were compared with those of uninfected cows. Twelve late-lactation Holsteins cows were paired based on milk production and parity. One cow in each pair was experimentally infected in the right front mammary gland with Strep. uberis. The remaining cow in each pair served as an uninfected control. Real-time analyses of milk constituents provided fat, protein, and lactose percentages at each milking. Pedometers were placed on the left front leg of all cows and activity was measured. Intramammary infections with Strep. uberis reduced milk yield in experimental cows by approximately 1.6kg/d in the first week after challenge compared with control cows. Lactose percentage in milk was reduced on d 3, 4, 5, and 6 after challenge in treatment cows compared with controls. Percentages of fat and protein in milk did not differ between infected and uninfected cows the week after infections were induced. Total steps per day were reduced and minutes resting per day were increased the week after experimental challenge in infected cows compared with control cows. The number of resting bouts did not differ between infected and uninfected cows. Changes in percentage of lactose in milk and animal activity caused by experimentally induced Strep. uberis mastitis were detected by the automated milk analyzer and pedometer systems. Copyright © 2015 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  6. Comparative experimental infection of Listeria monocytogenes and Listeria ivanovii in bovine trophoblasts.

    Science.gov (United States)

    Rocha, Cláudia E; Mol, Juliana P S; Garcia, Luize N N; Costa, Luciana F; Santos, Renato L; Paixão, Tatiane A

    2017-01-01

    Listeria monocytogenes is a Gram-positive, facultative intracellular and invasive bacterium that has tropism to the placenta, and causes fetal morbidity and mortality in several mammalian species. While infection with L. monocytogenes and L. ivanovii are known as important causes of abortion and reproductive failure in cattle, the pathogenesis of maternal-fetal listeriosis in this species is poorly known. This study used the bovine chorioallantoic membrane explant model to investigate the kinetics of L. monocytogenes, L. ivanovii, and L. innocua infections in bovine trophoblastic cells for up to 8 h post infection. L. monocytogenes and L. ivanovii were able to invade and multiply in trophoblastic cells without causing cell death or inducing expression of pro-inflammatory genes. Although L. innocua was unable to multiply in bovine trophoblastic cells, it induced transcription of the pro-inflammatory mediator CXCL6. This study demonstrated for the first time the susceptibility of bovine trophoblastic cells to L. monocytogenes and L. ivanovii infection.

  7. Brain infection following experimental Staphylococcus aureus sepsis in pigs

    DEFF Research Database (Denmark)

    Astrup, Lærke Boye; Iburg, Tine Moesgaard; Nielsen, Ole Lerberg

    2010-01-01

    Introduction: Sepsis is a major problem in humans and both the incidence and mortality is increasing. Multiple microabcesses can be found in the brain of septic patients. Staphylococcus aureus is one of the most common causes of sepsis and brain abscesses. S. aureus is also a frequent cause...... of spontaneous porcine pyemia including endocarditis and associated brain lesions. We present a porcine model of haematogenous S. aureus induced brain infection. Materials and Methods: Twelve pigs received an intravenous injection of S. aureus of 108 CFU/kg body weight once at 0h or twice at 0h and 12h. Four...... pigs were kept as controls. The pigs were euthanized in groups of four at either 6, 12, 24 or 48 h post infection. The brain was collected from all the animals and examined histologically. Results: All the inoculated pigs developed sepsis and 7 out of 12 animals had microabscesses in the prosencephalon...

  8. Superinfection occurs in Anaplasma phagocytophilum infected sheep irrespective of infection phase and protection status

    Directory of Open Access Journals (Sweden)

    Bergström Karin

    2009-10-01

    Full Text Available Abstract Background Anaplasma phagocytophilum infection in domestic ruminants is widespread in the coastal areas of southern Norway. The bacteria may persist in mammalian hosts. Several genetic variants of A. phagocytophilum exist. In the present study, we investigate whether superinfection occurs in the acute and persistent phase of the infection. Methods Five-month-old lambs of the Norwegian Dala breed were experimentally infected with two 16S rRNA gene variants of A. phagocytophilum, i.e. A. phagocytophilum variant 1 (GenBank accession number M73220 and variant 2 (GenBank acc. no. AF336220. Eighteen lambs were used, two lambs in each group. Eight groups were experimentally inoculated with either variant 1 or 2 on day 0. Six of these groups were then challenged with the other variant on either days 7, 42 or 84, respectively. One group was left uninfected. The occurrence of A. phagocytophilum in blood samples was determined using semi-nested PCR analysis and gene sequencing. Specific antibodies were measured by an indirect immunofluorescence antibody assay (IFA. Results A. phagocytophilum variant 1 and 2 differed significantly with regards to clinical reaction and cross-immunity in infected lambs. Both variants were found in the blood after challenge. However, variant 1 was detected most frequently. Conclusion The present experiment indicates that superinfection of different genotypes occurs during the acute as well as the persistent phase of an A. phagocytophilum infection, even in lambs protected against the challenged infection.

  9. Freeze-tolerance of Trichinella muscle larvae in experimentally infected wild boars.

    Science.gov (United States)

    Lacour, Sandrine A; Heckmann, Aurélie; Macé, Pauline; Grasset-Chevillot, Aurélie; Zanella, Gina; Vallée, Isabelle; Kapel, Christian M O; Boireau, Pascal

    2013-05-20

    Freeze-tolerance of encapsulated Trichinella muscle larvae (ML) is mainly determined by Trichinella species, but is also influenced by host species, the age of the infection and the storage time and temperature of the infected meat. Moreover, the freeze-tolerance of the encapsulated species appears to be correlated to the development of thick capsule walls which increases with age. An extended infection period and the muscle composition in some hosts (e.g. herbivores) may provide freeze-avoiding matrices due to high carbohydrate contents. The present experiment compares freeze-tolerance of Trichinella spiralis and Trichinella britovi ML in wild boar meat 24 weeks post inoculation (wpi). Three groups of four wild boars were infected with 200, 2000 or 20,000 ML of T. britovi (ISS 1575), respectively. Additionally, three wild boars were inoculated with 20,000 ML of T. spiralis (ISS 004) and two animals served as negative controls. All wild boars were sacrificed 24 wpi. Muscle samples of 70 g were stored at -21°C for 19, 30 and 56 h, and for 1-8 weeks. Larvae were recovered by artificial digestion. Their mobilities were recorded using Saisam(®) image analysis software and their infectivities were evaluated using mouse bioassays. Samples frozen for 19, 30 and 56 h allowed recovery of mobile ML, but samples frozen for 1 or 2 weeks did not. Correspondingly, only T. spiralis and T. britovi larvae isolated from wild boar meat frozen for 19, 30 and 56 h established in mice. This study showed that freezing at -21°C for 1 week inactivated T. spiralis and T. britovi ML encapsulated in wild boar meat for 24 weeks. Copyright © 2013 Elsevier B.V. All rights reserved.

  10. Increases In Plasma Urea And Creatinine In Experimental ...

    African Journals Online (AJOL)

    Alterations in both plasma urea and creatinine levels were monitored over a period of twenty eight (28) days in experimentally infected rabbits. A total of 15 animals were randomly divided into three groups of n=5. The groups were control (group I), infected and treated (group II) and infected but untreated (group III) ...

  11. Progression of experimental chronic Aleutian mink disease virus infection

    DEFF Research Database (Denmark)

    Jensen, Trine Hammer; Chriél, Mariann; Hansen, Mette Sif

    2016-01-01

    Aleutian mink disease virus (AMDV) is found world-wide and has a major impact on mink health and welfare by decreasing reproduction and fur quality. In the majority of mink, the infection is subclinical and the diagnosis must be confirmed by serology or polymerase chain reaction (PCR). Increased ...

  12. Efficacy of different instrumentation techniques on reducing Enterococcus faecalis infection in experimentally infected root canals

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    Ebru Özsezer Demiryürek

    2014-03-01

    Conclusion: This study indicates that instruments with a greater taper play an important role in maximizing the effectiveness of mechanical preparation. However, since using mechanical instrumentation alone is insufficient to completely eliminate root canal infection, the use of complementary antibacterial compounds is necessary.

  13. The effect of fermentable carbohydrates on experimental swine dysentery and whip worm infections in pigs

    DEFF Research Database (Denmark)

    Thomsen, Lisbeth E.; Knudsen, Knud Erik Bach; Jensen, Tim Kåre

    2007-01-01

    ingredients were composed. Both diets were based on triticale and barley and supplemented with either rape seed cake (Diet 1) or dried chicory root and sweet lupins (Diet 2). The study had a three-factorial design, with eight groups of pigs receiving Diet I or Diet 2, +/- B. hyodysenteriae, and +/- T suis......An experiment was conducted to study the effect of diets with contrasting fermentability in the large intestine on experimental infections with Brachyspira hyodysenteriae, the causative agent of swine dysentery, and the whip worm, Trichuris suis, in pigs. Two diets with organically grown....... Pigs fed Diet 2 and challenged with B. hyodysenteriae did not develop swine dysentery and B. hyodysenteriae was not demonstrated in any of the pigs during the study. In contrast, 94% of the B. hyodysenteriae challenged pigs fed Diet I showed clinical symptoms of swine dysentery and all the pigs were...

  14. Serological responses and immunity to superinfection with avian malaria in experimentally-infected Hawaii Amakihi

    Science.gov (United States)

    Atkinson, Carter T.; Dusek, Robert J.; Lease, Julie K.

    2001-01-01

    Six of seven Hawaii Amakihi (Hemignathus virens) with chronic malarial infections had no increases in peripheral parasitemia, declines in food consumption, or loss of body weight when rechallenged with the homologous isolate of Plasmodium relictum 61 to 62 days after initial infection. Five uninfected control amakihi exposed at the same time to infective mosquito bites developed acute infections with high parasitemias. Reductions in food consumption and loss of body weight occurred in all control birds and three of these individuals eventually died. When surviving birds were rechallenged >2 yr later with either the same parasite isolate or an isolate of P. relictum collected on the island of Kauai, all individuals were immune to superinfection. Chronically infected birds developed antibodies to a common suite of malarial antigens ranging in size from 22 to 170 kDa that were detectable as early as 8 days post infection on immunoblots of SDS-polyacrylamide gels. Antibodies to this suite of malarial antigens persisted as long as 1,248 days after initial infection and were consistently detectable at times when parasites were not easily found by microscopy on Giemsa-stained blood smears. The immunoblotting method that is described here appears to be an effective technique for identifying birds with chronic, low-intensity malarial infections when circulating parasites are not easily detectable by microscopy. Hawaiian honeycreepers that are capable of recovering from acute infections develop concomitant immunity to superinfection, making them functionally immune in areas where malaria transmission has become endemic.

  15. TNF-α is involved in the abnormal thymocyte migration during experimental Trypanosoma cruzi infection and favors the export of immature cells.

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    Ana Rosa Pérez

    Full Text Available Previous studies revealed a significant production of inflammatory cytokines together with severe thymic atrophy and thymocyte migratory disturbances during experimental Chagas disease. Migratory activity of thymocytes and mature T cells seem to be finely tuned by cytokines, chemokines and extracellular matrix (ECM components. Systemic TNF-α is enhanced during infection and appears to be crucial in the response against the parasite. However, it also seems to be involved in disease pathology, since it is implicated in the arrival of T cells to effector sites, including the myocardium. Herein, we analyzed the role of TNF-α in the migratory activity of thymocytes in Trypanosoma cruzi (T. cruzi acutely-infected mice. We found increased expression and deposition of TNF-α in the thymus of infected animals compared to controls, accompanied by increased co-localization of fibronectin, a cell migration-related ECM molecule, whose contents in the thymus of infected mice is also augmented. In-vivo studies showed an enhanced export of thymocytes in T. cruzi-infected mice, as ascertained by intrathymic injection of FITC alone or in combination with TNF-α. The increase of immature CD4(+CD8(+ T cells in secondary lymphoid organs was even more clear-cut when TNF-α was co-injected with FITC. Ex-vivo transmigration assays also revealed higher number of migrating cells when TNF-α was added onto fibronectin lattices, with higher input of all thymocyte subsets, including immature CD4(+CD8(+. Infected animals also exhibit enhanced levels of expression of both mRNA TNF-α receptors in the CD4(+CD8(+ subpopulation. Our findings suggest that in T. cruzi acute infection, when TNF-α is complexed with fibronectin, it favours the altered migration of thymocytes, promoting the release of mature and immature T cells to different compartments of the immune system. Conceptually, this work reinforces the notion that thymocyte migration is a multivectorial biological event

  16. Toxicity of polybrominated diphenyl ethers (de-71) in chicken (Gallus gallus), mallard (Anas platyrhynchos), and American kestrel (Falco sparverius) embryos and hatchlings

    Science.gov (United States)

    McKernan, M.A.; Rattner, B.A.; Hale, R.C.; Ottinger, M.A.

    2009-01-01

    Embryonic survival, pipping and hatching success, and sublethal biochemical, endocrine, and histological endpoints were examined in hatchling chickens (Gallus gallus), mallards (Anas platyrhynchos), and American kestrels (Falco sparverius) following air cell administration of a pentabrominated diphenyl ether (penta-BDE; DE-71) mixture (0.01-20 mu g/g egg) or polychlorinated biphenyl (PCB) congener 126 (3,3', 4,4', 5-pentachlorobiphenyl; 0.002 mu g/g egg). The penta-BDE decreased pipping and hatching success at concentrations of 10 and 20 mu g/g egg in kestrels but had no effect on survival endpoints in chickens or mallards. Sublethal effects in hatchling chickens included ethoxyresorufin-O-dealkylase (EROD) induction and histological changes in the bursa, but these responses were not observed in other species. Polychlorinated biphenyl congener 126 (positive control) reduced survival endpoints in chicken and kestrel embryos and caused sublethal effects (EROD induction, reduced bursal mass and follicle size) in chickens. Mallards were clearly less sensitive than the other species to administered penta-BDE and PCB 126. In a second experiment, the absorption of penta-BDE (11.1 mu g/g egg, air cell administered during early development) into the contents of chicken and kestrel eggs was determined at various intervals (24 h postinjection, midincubation, and pipping). By pipping, 29% of the penta-BDE administered dose was present in the egg contents in chickens, and 18% of the administered dose was present in kestrel egg contents. Based on uptake in kestrels, the lowest-observed-effect level on pipping and hatching success may be as low as 1.8 mu g total penta-BDE/g egg, which approaches concentrations detected in eggs of free-ranging birds. Because some penta-BDE congeners are still increasing in the environment, the toxic effects observed in the present study are cause for concern in wildlife.

  17. Experimental induction of struvite uroliths in miniature schnauzer and beagle dogs.

    Science.gov (United States)

    Klausner, J S; Osborne, C A; O'Leary, T P; Muscoplat, C M; Griffith, D P

    1980-09-01

    Urease positive staphylococcal urinary tract infection was experimentally induced in 13 dogs. Eight dogs developed cystic and/or urethral struvite calculi in 2 to 8 weeks. No abnormalities in systemic cell mediated immunity were detected in dogs before or after the establishment of the urinary tract infection. Miniature schnauzers whose ancestors had developed stones seemed to be no more susceptible to experimental urinary tract infection and stone formation than miniature schnauzers or beagles whose ancestors did not develop stones.

  18. Pelacakan Secara Imunohistokimiawi Antigen Virus pada Ayam yang Diinfeksi dengan Virus Penyakit Tetelo (IMMUNOHISTOCHEMICAL DETECTION OF VIRAL ANTIGEN IN TISSUE OF CHICKENS EXPERIMENTALLY INFECTED WITH NEWCASTLE DISEASE VIRUS

    Directory of Open Access Journals (Sweden)

    Anak Agung Ayu Mirah Adi

    2013-07-01

    Full Text Available In order to study the distribution of Newcastle disease virus (NDV following infection, chickenswere experimentally infected with visceretropic velogenic NDV isolate. Monoclonal antibodies (mAbsagainst the NDV LaSota vaccine strain were then produced to detect viral antigen in the infectedorgans. The mAbs were firstly tested for their specificity by enzyme linked immunosorbent assay(ELISA using NDV and normal allantoic fluids as antigens. Eight mAbs specific against NDVwere isolated and two mAbs were used for immunodetection of NDV antigen in chicken’s tissues.By immunohistochemistry labeled streptavidin-biotin (LSAB staining NDV–antigen was detectedin paraffin embedded tissues of NDV-infected chickens. NDV antigen was not detected in noninfected chickens. In the infected chickens, high intensity of NDV antigen was detected in thelymphoid tissues, lung and intestine. The NDV antigen with a lesser intensity was detected in thebrain, trachea, liver and myocardium. This study shows that although viscerotropic velogenicNDV isolate can infect almost all organs, the main target of infection are lung, intestine andlymphoids tissues

  19. Experimental infection in Notodiaptomus sp. (Crustacea: Calanoida with larvae of Camallanus sp. (Nematoda: Camallanidae Infecção experimental em Notodiaptomus sp. (Crustacea: Calanoida com larvas de Camallanus sp. (Nematoda: Camallanidae

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    M.L. Martins

    2007-04-01

    Full Text Available This trial registered the experimental infection viability with nematode larvae Camallanus sp. in Notodiaptomus sp., a crustacean, which can be an intermediate host. Adult females of nematode were dissected from the intestines of Xiphophorus maculatus (Osteichthyes: Poeciliidae, at a fish farm in the State of São Paulo. Females were slightly compressed for larvae release, collected with Pasteur pipette and separated on Petri dishes with 9ml filtered water at 28.1ºC, from zooplankton culture. Treatments consisted of Petri dishes with 60 and 105 copepods, in which 120, 150 and 210 larvae of nematode were added in four replications. Twenty-four and 36h after exposition to the larvae, the copepods were fixed in 70% alcohol to record the amount of fixed larvae. Twenty four hours after exposition, 60 copepods group with 120 larvae showed significantly higher prevalence (46.5% when compared to 105 copepods and 120 larvae (33.2%. Thus, these answers suggested that 120 larvae were enough for a successful infectivity. Experimental infection was available and so, it was used as a pattern to life cycle studies of camallanid nematodes and hosts susceptibility tests.A viabilidade da infecção experimental com larvas do nematóide Camallanus sp. em Notodiaptomus sp., crustáceo com potencial para hospedeiro intermediário foi avaliada. Fêmeas adultas do nematóide foram extraídas de Xiphophorus maculatus (Osteichthyes: Poeciliidae, provenientes de piscicultura de peixes ornamentais no estado de São Paulo. As fêmeas foram ligeiramente pressionadas para liberar as larvas, coletadas com pipeta Pasteur e separadas em placas de Petri contendo 9ml de água filtrada a 28,1ºC do próprio cultivo de zooplâncton. Os tratamentos consistiram de placas contendo 60 e 105 copépodes onde se adicionou 120, 150 e 210 larvas de nematóides em quatro repetições. Nos tempos de 24 e 36h após a exposição às larvas, os copépodes foram fixados em álcool 70% para

  20. Experimental infection of pregnant goats with bovine viral diarrhea virus (BVDV)1 or 2

    Science.gov (United States)

    Infections with bovine viral diarrhea virus (BVDV) of the genus pestivirus, family Flaviviridae, are not limited to cattle but occur in various artiodactyls. Persistently infected (PI) cattle are the main source of BVDV. Persistent infections also occur in heterologous hosts such as sheep and deer. ...

  1. Comparison of humoral response in sheep to Fasciola hepatica and Fasciola gigantica experimental infection

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    Zhang W.

    2004-06-01

    Full Text Available Humoral response of sheep to F. gigantica was compared with the well known humoral response to F. hepatica, in order to explain the difference of susceptibility of sheep to these two parasites. In this work, a lesser susceptibility of sheep to F. gigantica than to F. hepatica infection was confirmed. Humoral response to F. hepatica infection is similar to that previously described by several authors. IgG level of F. gigantica infected sheep increased from week 2 post-infection (2WPI and displayed a peak at 13WPI. F. gigantica excretory-secretory products (FgESP analyzed by SDS-PAGE showed at least 31 bands from 12.0 to 127.6 kDa in FgESP. Western blot indicated that F. gigantica infected sheep sera recognized, in FgESP, at least 30 antigens from 7.8 to 119.2 kDa of which 12 major bands recognized after OWPI. In FhESP and FgESP, F. hepatica infected sheep serum reacted only with the lower molecular mass antigens, while F. gigantica infected sheep serum reacted with the lower and the higher molecular mass antigens. These differences of antigenic recognition might be associated with the difference of susceptibility of sheep. Further investigation must be done to study the mechanism of resistance between the sheep infected with F. hepatica or F. gigantica.

  2. Block effect on HCV infection by HMGB1 released from virus-infected cells: An insight from mathematical modeling

    Science.gov (United States)

    Wang, Wei; Ma, Wanbiao

    2018-06-01

    The nuclear protein high-mobility group box 1 (HMGB1) can have an active role in deoxyribonucleic acid (DNA) organization and the regulation of transcription. Based on the new findings from a recent experimental study, the blocking effect on HCV infection by HMGB1 released from virus-infected cells is investigated using a diffusive model for viral infection dynamics. In the model, the diffusion of the virus depends not only on its concentration gradient, but also on the concentration of HMGB1. The basic reproduction number, threshold dynamics, stability properties of the steady states, travelling wave solutions, and spreading speed for the proposed model are studied. We show that the HMGB1-induced blocking of HCV infection slows the spread of virus compared with random diffusion only. Numerically, it is shown that a high concentration of HMGB1 can block the spread of virus and this confirms, not only qualitatively but also quantitatively, the experimental result.

  3. Immune response in rainbow trout against infection with Flavobacterium psychrophilum

    DEFF Research Database (Denmark)

    Henriksen, Maya Maria Mihályi; Kania, Per; Madsen, Lone

    farmers control the disease with antibiotics. The pathogen has a limited ability to cause disease in an experimental setting without applying a stressor. A bath-model using 150mg/L H2O2 for 60 minutes as a stressor was used on 1.4g rainbow trout fry in four experimental groups: 1) no H2O2/no bath...... infection, 2) H2O2/no bath infection, 3) no H2O2/ bath infection and 4) H2O2/ bath infection. Bath infections were carried out in 107 CFU/ml F. psychrophilum bath solution and control groups were bathed in sterile medium. Samples from all internal organs, head and skin were taken before pathogen exposure...

  4. Experimental mixed infection of Leishmania (Leishmania) amazonensis and Leishmania (L.) infantum in hamsters (Mesocricetus auratus).

    Science.gov (United States)

    DE Lima Celeste, Jordanna Luíza; Venuto Moura, Ana Paula; França-Silva, João Carlos; Matos DE Sousa, Gabriela; Oliveira Silva, Soraia; Norma Melo, Maria; Luiz Tafuri, Wagner; Carvalho Souza, Carolina; Monteiro DE Andrade, Hélida

    2017-08-01

    In South America, visceral leishmaniasis is frequently caused by Leishmania infantum and, at an unknown frequency, by Leishmania amazonensis. Therefore, mixed infections with these organisms are possible. Mixed infections might affect the clinical course, immune response, diagnosis, treatment and epidemiology of the disease. Here we describe the clinical course of mixed infections with L. amazonensis and L. infantum in a hamster model. We show that mixed infections are associated with more severe clinical disease than infection with L. amazonensis or L. infantum alone. In spleens with mixed infections, L. infantum outcompeted L. amazonensis in the tissue, but not in culture from tissue. We found increased levels of IgG in animals infected with L. infantum. Although more than 30 bands were revealed in a Western blot, the highest immunogenicity was observed with proteins having molecular masses of 95 and 90 kDa, whereas proteins with molecular masses of lower than 50 kDa were reactive frequently with serum from hamsters infected with L. amazonensis, and proteins with molecular masses of 80 and 70 kDa were reactive only with serum from hamsters infected with L. infantum. This finding has important implications regarding the biology of Leishmania and humoral immune responses to infections with these organisms.

  5. ORNITHOLOGICAL OBSERVATIONS ON THE VÂLCELE BASIN DURING FEBRUARY 2013 – JANUARY 2014

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    Adrian Mestecăneanu

    2014-06-01

    Full Text Available In this paper are showed the results of the researches performed during February 2013 – January 2014 on the avifauna from the Vâlcele Basin. The