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Sample records for experimentally infected avian

  1. Pathogenicity of avian malaria in experimentally-infected Hawaii Amakihi

    Science.gov (United States)

    Atkinson, Carter T.; Dusek, Robert J.; Woods, K.L.; Iko, W.M.

    2000-01-01

    The introduction of avian malaria (Plasmodium relictum) and mosquitoes (Culex quinquefasciatus) to the Hawaiian Islands (USA) is believed to have played a major role in the decline and extinction of native Hawaiian honeycreepers (Drepanidinae). This introduced disease is thought to be one of the primary factors limiting recovery of honeycreepers at elevations below 1,200 m where native forest habitats are still relatively intact. One of the few remaining species of honeycreepers with a wide elevational distribution is the Hawaii Amakihi (Hernignathus virens). We measured morbidity and mortality in experimentally-infected Hawaii Amakihi that were captured in a high elevation, xeric habitat that is above the current range of the mosquito vector. Mortality among amakihi exposed to a single infective mosquito bite was 65% (13/20). All infected birds had significant declines in food consumption and a corresponding loss in body weight over the 60 day course of the experiment. Gross and microscopic lesions in birds that succumbed to malaria included enlargement and discoloration of the spleen and liver and parasitemias as high as 50% of circulating erythrocytes. Mortality in experimentally-infected amakihi was similar to that observed in Apapane (Himnatione sanguinea) and lower than that observed in Iiwi (Vestiaria coccinea) infected under similar conditions with the same parasite isolate. We conclude that the current elevational and geographic distribution of Hawaiian honeycreepers is determined by relative susceptibility to avian malaria.

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

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    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.

  3. Avian toxoplasmosis: experimental infection of chicken and pigeon.

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    Biancifiori, F; Rondini, C; Grelloni, V; Frescura, T

    1986-01-01

    Two groups of 13 new-laying hens each were infected by crop-route with 5000 and 50,000 infective oocysts of T. gondii. Four groups of 5 pigeons each were inoculated by crop-route with 50, 500, 1000 and 5000 infective oocysts. To each group of infected birds suitable controls were added. Hens from the experiment with 5000 infective oocysts were apparently resistant to the infection and they had no clinical signs in the succeeding 40 days p.i. Hens from the experiment with 50,000 infective oocysts showed an egg-drop and mortality in embryonated eggs, especially during the first 2 weeks p.i. Isolation of the parasite was unsuccessfully attempted from 720 embryonated eggs, produced by infected groups, and tested on various days p.i. and at different stages of infection. The parasite was isolated from the brain, heart, liver, spleen and lung of infected birds 7 and 15 days p.i.; 40 days p.i. it was evident only in brain and heart. IgG onset and mean course were monitored by ELISA and high titers were reached by both groups. Pigeons from groups 500, 1000 and 5000 developed rapidly progressive clinical signs as diarrhea, trembling, incoordination, torticollis and death. They had enlargement of liver and spleen and focal necrosis, nodular features in the crop. Pigeons from expt 50 had no clinical signs in spite of the presence of the parasite in their organs for over 45 days p.i. Parasite was isolated from brain, heart, liver, spleen, lung, kidney, crop and muscles from all infected groups. Histopathological and ultrastructural features revealed the presence of multiplying tachizoites even within cells of the crop. Seroconversion, as monitored by ELISA, was recorded in all infected groups although high ELISA-titres were never reached. One of the negative controls from expt 5000 developed specific antibodies but the parasite was not isolated from its organs.

  4. 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

  5. Experimental infection of hamsters with avian paramyxovirus serotypes 1 to 9

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    Samuel Arthur S

    2011-02-01

    Full Text Available Abstract Avian paramyxoviruses (APMVs are frequently isolated from domestic and wild birds throughout the world and are separated into nine serotypes (APMV-1 to -9. Only in the case of APMV-1, the infection of non-avian species has been investigated. The APMVs presently are being considered as human vaccine vectors. In this study, we evaluated the replication and pathogenicity of all nine APMV serotypes in hamsters. The hamsters were inoculated intranasally with each virus and monitored for clinical disease, pathology, histopathology, virus replication, and seroconversion. On the basis of one or more of these criteria, each of the APMV serotypes was found to replicate in hamsters. The APMVs produced mild or inapparent clinical signs in hamsters except for APMV-9, which produced moderate disease. Gross lesions were observed over the pulmonary surface of hamsters infected with APMV-2 & -3, which showed petechial and ecchymotic hemorrhages, respectively. Replication of all of the APMVs except APMV-5 was confirmed in the nasal turbinates and lungs, indicating a tropism for the respiratory tract. Histologically, the infection resulted in lung lesions consistent with bronchointerstitial pneumonia of varying severity and nasal turbinates with blunting or loss of cilia of the epithelium lining the nasal septa. The majority of APMV-infected hamsters exhibited transient histological lesions that self resolved by 14 days post infection (dpi. All of the hamsters infected with the APMVs produced serotype-specific HI or neutralizing antibodies, confirming virus replication. Taken together, these results demonstrate that all nine known APMV serotypes are capable of replicating in hamsters with minimal disease and pathology.

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

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    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

  7. Avian Influenza A Virus Infections in Humans

    Science.gov (United States)

    ... Pandemic Other Avian Influenza A Virus Infections in Humans Language: English (US) Español Recommend on Facebook Tweet ... A Viruses Avian Influenza A Virus Infections in Humans Although avian influenza A viruses usually do not ...

  8. Adaptive Heterosubtypic Immunity to Low Pathogenic Avian Influenza Viruses in Experimentally Infected Mallards.

    Science.gov (United States)

    Segovia, Karen M; Stallknecht, David E; Kapczynski, Darrell R; Stabler, Lisa; Berghaus, Roy D; Fotjik, Alinde; Latorre-Margalef, Neus; França, Monique S

    2017-01-01

    Mallards are widely recognized as reservoirs for Influenza A viruses (IAV); however, host factors that might prompt seasonality and trends in subtype diversity of IAV such as adaptive heterosubtypic immunity (HSI) are not well understood. To investigate this, we inoculated mallards with a prevailing H3N8 low pathogenic avian influenza virus (LPAIV) subtype in waterfowl to determine if prior infection with this virus would be protective against heterosubtypic infections with the H4N6, H10N7 and H14N5 LPAIV subtypes after one, two and three months, respectively. Also, we investigated the effect of cumulative immunity after sequential inoculation of mallards with these viruses in one-month intervals. Humoral immunity was assessed by microneutralization assays using a subset of representative LPAIV subtypes as antigens. Our results indicate that prior inoculation with the H3N8 virus confers partial protective immunity against subsequent heterosubtypic infections with the robustness of HSI related to the phylogenetic similarity of the HA protein of the strains used. Furthermore, induced HSI was boosted and followed by repeated exposure to more than one LPAIV subtype. Our findings provide further information on the contributions of HSI and its role in the dynamics of IAV subtype diversity in mallards.

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

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    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

  10. Survival of Highly Pathogenic Avian Influenza H5N1 Virus in Tissues Derived from Experimentally Infected Chickens.

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    Yamamoto, Yu; Nakamura, Kikuyasu; Mase, Masaji

    2017-08-15

    Eurasian lineage highly pathogenic avian influenza (HPAI) H5N1 virus has been a severe threat to the poultry industry since its emergence in 1996. The carcass or tissues derived from infected birds may present the risk of the virus spreading to humans, animals, and the surrounding environment. In this study, we investigated the survival of the virus in feather, muscle, and liver tissues collected from six chickens (Gallus gallus) experimentally infected with HPAI H5N1 virus. The tissues were stored at +4°C or +20°C, and viral isolation was performed at different times for 360 days. The maximum periods for viral survival were observed in samples stored at +4°C in all tissue types and were 240 days in feather tissues, 160 days in muscle, and 20 days in liver. The viral infectivity at +20°C was maintained for a maximum of 30 days in the feather tissues, 20 days in muscle, and 3 days in liver. The viral inactivation rates partly overlapped in the feather and muscle tissues at the two temperatures. The virus was inactivated rapidly in the liver. Our experimental results indicate that the tissue type and temperature can greatly influence the survival of HPAI H5N1 virus in the tissues of infected chickens.IMPORTANCE Highly pathogenic avian influenza virus of the H5N1 subtype can cause massive losses of poultry, and people need to handle a large number of chicken carcasses contaminated with the virus at outbreak sites. This study evaluated how long the virus can keep its infectivity in the three types of tissues derived from chickens infected with the virus. Our experimental results indicate that the virus can survive in tissues for a specific period of time depending on the tissue type and temperature. Our results are valuable for better understanding of viral ecology in the environment and for reducing the risk of the virus spreading via bird tissues contaminated with the virus. Copyright © 2017 American Society for Microbiology.

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

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    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.

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

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    Márcia B. dos Santos

    2012-12-01

    Full Text Available Avian metapneumovirus (aMPV is a respiratory pathogen associated with the swollen head syndrome (SHS in chickens. In Brazil, live aMPV vaccines are currently used, but subtypes A and, mainly subtype B (aMPV/A and aMPV/B are still circulating. This study was conducted to characterize two Brazilian aMPV isolates (A and B subtypes of chicken origin. A challenge trial to explore the replication ability of the Brazilian subtypes A and B in chickens was performed. Subsequently, virological protection provided from an aMPV/B vaccine against the same isolates was analyzed. Upon challenge experiment, it was shown by virus isolation and real time PCR that aMPV/B could be detected longer and in higher amounts than aMPV/A. For the protection study, 18 one-day-old chicks were vaccinated and challenged at 21 days of age. Using virus isolation and real time PCR, no aMPV/A was detected in the vaccinated chickens, whereas one vaccinated chicken challenged with the aMPV/B isolate was positive. The results showed that aMPV/B vaccine provided a complete heterologous virological protection, although homologous protection was not complete in one chicken. Although only one aMPV/B positive chicken was detected after homologous vaccination, replication in vaccinated animals might allow the emergence of escape mutants.

  13. Avian Influenza infection in Human

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    Mohan. M

    2008-08-01

    Full Text Available Outbreaks caused by the H5N1 strain are presently of the greatest concern for human health. In assessing risks to human health, it is important to know exactly which avian virus strains are causing the outbreaks in birds.All available evidence points to an increased risk of transmission to humans when outbreaks of highly pathogenic avian H5N1 influenza are widespread in poultry. There is mounting evidence that this strain has a unique capacity to jump the species barrier and cause severe disease, with high mortality, in humans. There is no evidence, to date that efficient human to human transmission of H5N1 strain has occurred and very often. Efficient transmission among humans is a key property of pandemic strains and a property that the avian H5N1 and H9N2 viruses apparently lacked. The biological and molecular basis for effective aerosol transmission among humans is not known. The virus can improve its transmissibility among humans via two principal mechanisms. The first is a “reassortment” event, in which genetic material is exchanged between human and avian viruses during co-infection of a human or pig.Reassortment could result in a fully transmissible pandemic virus, announced by a sudden surge of cases with explosive spread. The second mechanism is a more gradual process of adaptive mutation, whereby the capability of the virus to bind to human cells increases during subsequent infections of humans. Adaptive mutation, expressed initially as small clusters of human cases with some evidence of human-to-human transmission, would probably give the world some time to take defensive action, if detected sufficiently early. As the number of human infections grows, the risk increases that a new virus subtype could emerge, triggering an influenza pandemic. Humans as well as swine must now be considered a potential mixing vessel for the generation of such a virus. This link between widespread infection in poultry and increased risk of human

  14. Wildlife disease and conservation in Hawaii: pathogenicity of avian malaria (Plasmodium relictum) in experimentally infected Iiwi (Vestiaria coccinea)

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    Atkinson, C.T.; Woods, K.L.; Dusek, Robert J.; Sileo, L.S.; Iko, W.M.

    1995-01-01

    Native Hawaiian forest birds are facing a major extinction crisis with more than 75% of species recorded in historical times either extinct or endangered. Reasons for this catastrophe include habitat destruction, competition with non-native species, and introduction of predators and avian diseases. We tested susceptibility of Iiwi (Vestiaria coccinea), a declining native species, and Nutmeg Mannikins (Lonchura punctulata), a common non-native species, to an isolate of Plasmodium relictum from the island of Hawaii. Food consumption, weight, and parasitaemia were monitored in juvenile Iiwi that were infected by either single (low-dose) or multiple (high-dose) mosquito bites. Mortality in both groups was significantly higher than in uninfected controls, reaching 100% of high-dose birds and 90% of low-dose birds. Significant declines in food consumption and a corresponding loss of body weight occurred in malaria-infected birds. Both sex and body weight had significant effects on survival time, with males more susceptible than females and birds with low initial weights more susceptible than those with higher initial weights. Gross and microscopic lesions in malaria fatalities included massive enlargement of the spleen and liver, hyperplasia of the reticuloendothelial system with extensive deposition of malarial pigment, and overwhelming anaemia in which over 30% of the circulating erythrocytes were parasitized. Nutmeg Mannikins, by contrast, were completely refractory to infection. Our findings support previous studies documenting high susceptibility of native Hawaiian forest birds to avian malaria. This disease continues to threaten remaining high elevation populations of endangered native birds.

  15. Comparison of the efficacy of four antimicrobial treatment schemes against experimental Ornithobacterium rhinotracheale infection in turkey poults pre-infected with avian pneumovirus.

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    Marien, Maja; Nauwynck, Hans; Duchateau, Luc; Martel, An; Chiers, Koen; Devriese, Luc; Froyman, Robrecht; Decostere, Annemie

    2006-06-01

    The clinical efficacy of drinking-water administration of enrofloxacin for 3 and 5 days, amoxicillin for 5 days and florfenicol for 5 days for the treatment of respiratory disease induced by an experimental Ornithobacterium rhinotracheale infection in turkeys pre-infected with avian pneumovirus (APV) was assessed based on clinical, bacteriological and histopathological examinations. Experimental groups of 15 susceptible 3-week-old turkeys were each inoculated oculonasally with APV subtype A and 3 days later with susceptible O. rhinotracheale bacteria. Antimicrobial treatment started 1 day after O. rhinotracheale inoculation. After infection, the birds were examined and scored for clinical signs, swabbed daily and weighed at different times. Five birds were euthanized and examined for macroscopic lesions at necropsy at 5 days post bacterial inoculation, and the remainder at 15 days post bacterial inoculation. Samples of the turbinates, trachea, lungs, air sacs, heart and pericardium were collected for bacteriological and/or histological examination. Recovery from respiratory disease caused by an APV/O. rhinotracheale dual infection was most successful after enrofloxacin treatment, irrespective of treatment duration, followed by florfenicol. Amoxicillin treatment was not efficacious. Clinical signs and the number of O. rhinotracheale organisms re-isolated from the trachea and the different respiratory organs were significantly reduced by enrofloxacin treatment for 3 and 5 days. O. rhinotracheale bacteria were not re-isolated from the tracheas of the birds treated with enrofloxacin except for one bird in the 5-day group, as early as 1 day after medication onset. In the group treated with enrofloxacin for 5 days, O. rhinotracheale organisms with a higher minimal inhibitory concentration value (x8) were isolated starting 2 days following treatment onset, initially from a single turkey and subsequently from the other animals.

  16. 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 up......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...... 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...

  17. 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.

  18. Experimental infection of a North American raptor, American kestrel (Falco sparverius), with highly pathogenic avian influenza virus (H5N1)

    Science.gov (United States)

    Hall, J.S.; Ip, H.S.; Franson, J.C.; Meteyer, C.; Nashold, S.; Teslaa, J.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.

  19. Histopathological and immunohistochemical study of exocrine and endocrine pancreatic lesions in avian influenza A experimentally infected turkeys showing evidence of pancreatic regeneration.

    Science.gov (United States)

    Cavicchioli, Laura; Zappulli, Valentina; Beffagna, Giorgia; Caliari, Diego; Zanetti, Rossella; Nordio, Laura; Mainenti, Marta; Frezza, Federica; Bonfante, Francesco; Patrono, Livia Victoria; Capua, Ilaria; Terregino, Calogero

    2015-01-01

    In order to investigate the pancreatic lesions caused by the infection with either H7N1 or H7N3 low-pathogenicity avian influenza viruses, 28 experimentally infected turkeys were submitted for histopathology, immunohistochemistry, haematobiochemistry and real-time reverse transcriptase polymerase chain reaction after different days post-infection (DPI). The localization of viral antigen and the measurement of insulin and glucagon expression in the pancreas were assessed to verify the progression from pancreatitis to metabolic disorders, such as diabetes. At the early infection phase (4-7 DPI), a severe acute necrotizing pancreatitis was recognized. During the intermediate phase (8-17 DPI), a mixed acute/chronic change associated with regenerative ductular proliferation was observed. A loss of pancreatic islets was detected in most severe cases and viral antigen was found in the pancreas of 11/28 turkeys (4-10 DPI) with the most severe histological damage. In turkeys euthanized at 39 DPI (late phase), a chronic fibrosing pancreatitis was observed with the reestablishment of both the exocrine and the endocrine pancreas. Insulin and glucagon expression manifested a progressive decrease with subsequent ductular positivity. Haematobiochemistry revealed increased lipasemia in the first week post-infection and hyperglycaemia in the second, with a progressive normalization within 21 DPI. This study allowed the identification of progressive virus-associated exocrine and endocrine pancreatic damage, suggesting that influenza virus might be responsible for metabolic derangements. Moreover, it highlighted a remarkable post-damage hyperplastic and reparative process from a presumptive common exocrine/endocrine precursor. This potential regeneration deserves further investigation for its relevance in a therapeutic perspective to replace lost and non-functional cells in diabetes mellitus.

  20. Avian Influenza Infection in Humans

    African Journals Online (AJOL)

    Pulmonology Unit, Department of Medicine,. University College Hospital, Ibadan. INTRODUCTION _ ... saliva, nasal secretions and faeces. Susceptible birds become infected when they have contact with con- .... ing and immunofluorescence[l4, 1 5]. Laboratory tests are required for specific identification of avian. influenza.

  1. Experimentally infected domestic ducks show efficient transmission of Indonesian H5N1 highly pathogenic avian influenza virus, but lack persistent viral shedding.

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    Hendra Wibawa

    Full Text Available Ducks are important maintenance hosts for avian influenza, including H5N1 highly pathogenic avian influenza viruses. A previous study indicated that persistence of H5N1 viruses in ducks after the development of humoral immunity may drive viral evolution following immune selection. As H5N1 HPAI is endemic in Indonesia, this mechanism may be important in understanding H5N1 evolution in that region. To determine the capability of domestic ducks to maintain prolonged shedding of Indonesian clade 2.1 H5N1 virus, two groups of Pekin ducks were inoculated through the eyes, nostrils and oropharynx and viral shedding and transmission investigated. Inoculated ducks (n = 15, which were mostly asymptomatic, shed infectious virus from the oral route from 1 to 8 days post inoculation, and from the cloacal route from 2-8 dpi. Viral ribonucleic acid was detected from 1-15 days post inoculation from the oral route and 1-24 days post inoculation from the cloacal route (cycle threshold <40. Most ducks seroconverted in a range of serological tests by 15 days post inoculation. Virus was efficiently transmitted during acute infection (5 inoculation-infected to all 5 contact ducks. However, no evidence for transmission, as determined by seroconversion and viral shedding, was found between an inoculation-infected group (n = 10 and contact ducks (n = 9 when the two groups only had contact after 10 days post inoculation. Clinical disease was more frequent and more severe in contact-infected (2 of 5 than inoculation-infected ducks (1 of 15. We conclude that Indonesian clade 2.1 H5N1 highly pathogenic avian influenza virus does not persist in individual ducks after acute infection.

  2. Common avian infection plagued the tyrant dinosaurs.

    Directory of Open Access Journals (Sweden)

    Ewan D S Wolff

    Full Text Available BACKGROUND: Tyrannosaurus rex and other tyrannosaurid fossils often display multiple, smooth-edged full-thickness erosive lesions on the mandible, either unilaterally or bilaterally. The cause of these lesions in the Tyrannosaurus rex specimen FMNH PR2081 (known informally by the name 'Sue' has previously been attributed to actinomycosis, a bacterial bone infection, or bite wounds from other tyrannosaurids. METHODOLOGY/PRINCIPAL FINDINGS: We conducted an extensive survey of tyrannosaurid specimens and identified ten individuals with full-thickness erosive lesions. These lesions were described, measured and photographed for comparison with one another. We also conducted an extensive survey of related archosaurs for similar lesions. We show here that these lesions are consistent with those caused by an avian parasitic infection called trichomonosis, which causes similar abnormalities on the mandible of modern birds, in particular raptors. CONCLUSIONS/SIGNIFICANCE: This finding represents the first evidence for the ancient evolutionary origin of an avian transmissible disease in non-avian theropod dinosaurs. It also provides a valuable insight into the palaeobiology of these now extinct animals. Based on the frequency with which these lesions occur, we hypothesize that tyrannosaurids were commonly infected by a Trichomonas gallinae-like protozoan. For tyrannosaurid populations, the only non-avian dinosaur group that show trichomonosis-type lesions, it is likely that the disease became endemic and spread as a result of antagonistic intraspecific behavior, consumption of prey infected by a Trichomonas gallinae-like protozoan and possibly even cannibalism. The severity of trichomonosis-related lesions in specimens such as Tyrannosaurus rex FMNH PR2081 and Tyrannosaurus rex MOR 980, strongly suggests that these animals died as a direct result of this disease, mostly likely through starvation.

  3. Common Avian Infection Plagued the Tyrant Dinosaurs

    Science.gov (United States)

    Wolff, Ewan D. S.; Salisbury, Steven W.; Horner, John R.; Varricchio, David J.

    2009-01-01

    Background Tyrannosaurus rex and other tyrannosaurid fossils often display multiple, smooth-edged full-thickness erosive lesions on the mandible, either unilaterally or bilaterally. The cause of these lesions in the Tyrannosaurus rex specimen FMNH PR2081 (known informally by the name ‘Sue’) has previously been attributed to actinomycosis, a bacterial bone infection, or bite wounds from other tyrannosaurids. Methodology/Principal Findings We conducted an extensive survey of tyrannosaurid specimens and identified ten individuals with full-thickness erosive lesions. These lesions were described, measured and photographed for comparison with one another. We also conducted an extensive survey of related archosaurs for similar lesions. We show here that these lesions are consistent with those caused by an avian parasitic infection called trichomonosis, which causes similar abnormalities on the mandible of modern birds, in particular raptors. Conclusions/Significance This finding represents the first evidence for the ancient evolutionary origin of an avian transmissible disease in non-avian theropod dinosaurs. It also provides a valuable insight into the palaeobiology of these now extinct animals. Based on the frequency with which these lesions occur, we hypothesize that tyrannosaurids were commonly infected by a Trichomonas gallinae-like protozoan. For tyrannosaurid populations, the only non-avian dinosaur group that show trichomonosis-type lesions, it is likely that the disease became endemic and spread as a result of antagonistic intraspecific behavior, consumption of prey infected by a Trichomonas gallinae-like protozoan and possibly even cannibalism. The severity of trichomonosis-related lesions in specimens such as Tyrannosaurus rex FMNH PR2081 and Tyrannosaurus rex MOR 980, strongly suggests that these animals died as a direct result of this disease, mostly likely through starvation. PMID:19789646

  4. Experimental infection with low and high pathogenicity H7N3 Chilean avian influenza viruses in Chiloe wigeon (Anas sibilatrix) and cinnamon teal (Anas cyanoptera).

    Science.gov (United States)

    Sá e Silva, Mariana; Mathieu-Benson, Christian; Kwon, Yong-Kuk; Pantin-Jackwood, Mary; Swayne, David E

    2011-09-01

    Two different wild duck species common in Chile and neighboring countries, Chiloe wigeon (Anas sibilatrix) and cinnamon teal (Anas cyanoptera), were intranasally inoculated with 10(6) mean embryo infective dose (EID50) of the H7N3 low pathogenicity (LP) avian influenza virus (AIV) (A/chicken/Chile/176822/02) or high pathogenicity (HP) AIV (A/chicken/Chile/ 184240-1/02), in order to study the infectivity and pathobiology of these viruses. None of the virus-inoculated ducks had clinical signs or died, but most seroconverted by 14 days postinoculation (DPI), indicating a productive virus infection. Both LPAIV and HPAIV were isolated from oral swabs from two of six Chiloe wigeons and from oral and/or cloacal swabs from all five of the cinnamon teal at 2 DPI. Both LPAIV and HPAIV were efficiently transmitted to cinnamon teal contacts but not to Chiloe wigeon contacts. This study demonstrates that the cinnamon teal and Chiloe wigeons were susceptible to infection with both Chilean H7N3 LPAIV and HPAIV, but only the cinnamon teal showed contact transmission of the virus between birds, suggesting that the cinnamon teal has the potential to be a reservoir for these viruses, especially the LPAIV, as was demonstrated in 2001 with isolation of a genetically related H7N3 LPAIV strain in a cinnamon teal in Bolivia. However, the definitive source of the H7N3 Chilean LPAIV still remains unknown.

  5. Infection of Avian Pox Virus in Oriental Turtle-Doves

    Directory of Open Access Journals (Sweden)

    Kyung-Yeon Eo1, Young-Hoan Kim2, Kwang-Hyun Cho3, Jong-Sik Jang4, Tae-Hwan Kim5, Dongmi Kwak5 and Oh-Deog Kwon5*

    2011-10-01

    Full Text Available Three Oriental Turtle-doves (Streptopelia orientalis exhibiting lethargy, dyspnea, poor physical condition, and poor flight endurance, were rescued and referred to the Animal Health Center, Seoul Zoo, Korea. The doves had wart-like lesions on the legs and head. All of them died the following day after arrival, with the exception of one that survived for 6 days. Diphtheritic membranes on the tongue and oral mucosa were apparent at necropsy. Avian pox virus infection was suspected based on the proliferative skin lesions and oral diphtheritic lesions. Infection of the avian pox virus was confirmed by PCR using primers specific to the 4b core protein gene of avian pox virus. All cases were diagnosed with avian pox virus infection. This is believed to be the first description on natural infection of avian pox in Oriental Turtle-doves in Korea.

  6. Experimental induced avian E. coli salpingitis

    DEFF Research Database (Denmark)

    Olsen, Rikke Heidemann; Thøfner, Ida; Pors, Susanne Elisabeth

    2016-01-01

    Several types of Escherichia coli have been associated with extra-intestinal infections in poultry, however, they may vary significantly in their virulence potential. The aim of the present study was to investigate the virulence of five strains of E. coli obtained from different disease......) had a distinct ability to cause disease. Results of the study shows major differences in virulence of different strains of E. coli in ascending infections; however, there was no indication of tissue-specific adaptation, since strains obtained from lesions unrelated to the reproductive system were...... fully capable of causing experimental infection. In conclusion, the study provides evidence for the clinical outcome of infection with E. coli in poultry is largely influenced by the specific strain as well as individual host factors....

  7. Plasmodium spp.: an experimental study on vertebrate host susceptibility to avian malaria.

    Science.gov (United States)

    Dimitrov, Dimitar; Palinauskas, Vaidas; Iezhova, Tatjana A; Bernotienė, Rasa; Ilgūnas, Mikas; Bukauskaitė, Dovile; Zehtindjiev, Pavel; Ilieva, Mihaela; Shapoval, Anatoly P; Bolshakov, Casimir V; Markovets, Mikhail Yu; Bensch, Staffan; Valkiūnas, Gediminas

    2015-01-01

    The interest in experimental studies on avian malaria caused by Plasmodium species has increased recently due to the need of direct information about host-parasite interactions. Numerous important issues (host susceptibility, development of infection, the resistance and tolerance to avian malaria) can be answered using experimental infections. However, specificity of genetically different lineages of malaria parasites and their isolates is largely unknown. This study reviews recent experimental studies and offers additional data about susceptibility of birds to several widespread cytochrome b (cyt b) lineages of Plasmodium species belonging to four subgenera. We exposed two domesticated avian hosts (canaries Serinus canaria and ducklings Anas platyrhynchos) and also 16 species of common wild European birds to malaria infections by intramuscular injection of infected blood and then tested them by microscopic examination and PCR-based methods. Our study confirms former field and experimental observations about low specificity and wide host-range of Plasmodium relictum (lineages SGS1 and GRW11) and P. circumflexum (lineage TURDUS1) belonging to the subgenera Haemamoeba and Giovannolaia, respectively. However, the specificity of different lineages and isolates of the same parasite lineage differed between species of exposed hosts. Several tested Novyella lineages were species specific, with a few cases of successful development in experimentally exposed birds. The majority of reported cases of mortality and high parasitaemia were observed during parasite co-infections. Canaries were susceptible mainly for the species of Haemamoeba and Giovannolaia, but were refractory to the majority of Novyella isolates. Ducklings were susceptible to three malaria infections (SGS1, TURDUS1 and COLL4), but parasitaemia was light (<0.01%) and transient in all exposed birds. This study provides novel information about susceptibility of avian hosts to a wide array of malaria parasite

  8. 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

    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...... 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......, the mortality of the mallards ranged from nil to 100%, which suggests that Muscovy ducks are more susceptible to HPAIV H5N1 infection in terms of disease development and mortality. It was also found that higher virus titers developed in vital organs of Muscovy ducks compared to mallards, particularly...

  9. A method to preserve low parasitaemia Plasmodium-infected avian blood for host and vector infectivity assays.

    Science.gov (United States)

    Carlson, Jenny S; Giannitti, Federico; Valkiūnas, Gediminas; Tell, Lisa A; Snipes, Joy; Wright, Stan; Cornel, Anthony J

    2016-03-11

    Avian malaria vector competence studies are needed to understand more succinctly complex avian parasite-vector-relations. The lack of vector competence trials may be attributed to the difficulty of obtaining gametocytes for the majority of Plasmodium species and lineages. To conduct avian malaria infectivity assays for those Plasmodium spp. and lineages that are refractory to in vitro cultivation, it is necessary to obtain and preserve for short periods sufficient viable merozoites to infect naïve donor birds to be used as gametocyte donors to infect mosquitoes. Currently, there is only one described method for long-term storage of Plasmodium spp.-infected wild avian blood and it is reliable at a parasitaemia of at least 1%. However, most naturally infected wild-caught birds have a parasitaemia of much less that 1%. To address this problem, a method for short-term storage of infected wild avian blood with low parasitaemia (even ≤ 0.0005%) has been explored and validated. To obtain viable infective merozoites, blood was collected from wild birds using a syringe containing the anticoagulant and the red blood cell preservative citrate phosphate dextrose adenine solution (CPDA). Each blood sample was stored at 4 °C for up to 48 h providing sufficient time to determine the species and parasitaemia of Plasmodium spp. in the blood by morphological examination before injecting into donor canaries. Plasmodium spp.--infected blood was inoculated intravenously into canaries and once infection was established, Culex stigmatosoma, Cx. pipiens and Cx. quinquefasciatus mosquitoes were then allowed to feed on the infected canaries to validate the efficacy of this method for mosquito vector competence assays. Storage of Plasmodium spp.--infected donor blood at 4 °C yielded viable parasites for 48 h. All five experimentally-infected canaries developed clinical signs and were infectious. Pathologic examination of three canaries that later died revealed splenic lesions typical of

  10. Experimental induction and oral transmission of avian AA amyloidosis in vaccinated white hens.

    Science.gov (United States)

    Murakami, Tomoaki; Muhammad, Naeem; Inoshima, Yasuo; Yanai, Tokuma; Goryo, Masanobu; Ishiguro, Naotaka

    2013-06-01

    Avian AA amyloidosis is commonly observed in adult birds afflicted with bacterial infections or chronic inflammatory disorders. Experimental AA amyloidosis in birds can be induced by repeated inflammatory stimulation, such as injection with casein or vaccination with oil-emulsified bacterins. However, the transmission of amyloidosis among avian species has not been studied well to date. In the present study, we confirm the potential induction of avian AA amyloidosis by inoculation of Salmonella enteritidis (SE) vaccine or Mycoplasma gallisepticum vaccine. To determine the transmission of chicken AA amyloidosis among white hens, we induced experimental AA amyloidosis in vaccinated chickens by intravenous or oral administration of chicken AA fibrils. Amyloid deposits were observed in chickens injected with SE and inoculated with chicken AA fibrils intravenously (21/26: 81%) and orally (8/12: 67%). These results suggest that chicken AA amyloidosis can be induced by vaccinations, and may be transmitted among like species by oral administration.

  11. Reduced experimental infectivity and transmissibility of intercontinental H5 (H5N8 and H5N2) compared to Eurasian H5N1 highly pathogenic avian influenza viruses for chickens, turkeys, and Japanese quail

    Science.gov (United States)

    H5N1 high pathogenicity avian influenza (HPAI) virus (HPAIV) emerged in 1996 in Guangdong China and has since spread to infect and cause deaths in wild birds, poultry and humans in over 63 countries in Asia, Europe and Africa; and more recently a reassortant H5N8 clade 2.3.4.4 HPAI virus has spread ...

  12. 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.

  13. Avian bornavirus in the urine of infected birds

    Directory of Open Access Journals (Sweden)

    Villalobos AR

    2012-06-01

    Full Text Available J Jill Heatley,1 Alice R Villalobos21Zoological Medicine, 2Department of Nutrition & Food Science, Texas A&M University, College of Veterinary Medicine and Biomedical Sciences, College Station, TX, USAAbstract: Avian bornavirus (ABV causes proventricular dilatation disease in multiple avian species. In severe clinical disease, the virus, while primarily neurotropic, can be detected in many organs, including the kidneys. We postulated that ABV could be shed by the kidneys and found in the urine of infected birds. Immunohistochemical staining demonstrated viral N and P proteins of ABV within the renal tubules. We adapted a nonsurgical method of urine collection for use in parrots known to be shedding ABV in their droppings. We obtained urine without feces, and results were compared with swabs of fresh voided feces. Reverse transcription–polymerase chain reaction assay performed on these paired samples from five birds indicated that ABV was shed in quantity in the urine of infected birds, and a single sample was urine-positive and fecal-negative. We suggest that urine sampling may be a superior sample for detection of birds shedding ABV, and advocate that additional birds, known to be shedding or infected with ABV, should be investigated via this method.Keywords: avian bornavirus, Psittaciformes, parrot, urine, proventricular dilatation disease

  14. Decreased egg production in laying hens associated with infection with genotype 3 avian hepatitis E virus strain from China.

    Science.gov (United States)

    Zhao, Qin; Liu, Baoyuan; Sun, Yani; Du, Taofeng; Chen, Yiyang; Wang, Xinjie; Li, Huixia; Nan, Yuchen; Zhang, Gaiping; Zhou, En-Min

    2017-05-01

    To determine the relationship between decreased egg production and avian HEV infection, thirty healthy 23-week-old Hy-Line Variety Brown layer hens were randomly divided into 3 groups with 10 hens per group. Next, a genotype 3 avian HEV strain from China was used to inoculate laying hens via oronasal or intravenous routes using a 50% chicken infectious dose of 500. All hens were necropsied at 14 weeks postinoculation (wpi). Fecal virus shedding, viremia, seroconversion, serum alanine aminotransferase (ALT) increases and liver lesions showed that after intravenous (i.v.) and oronasal inoculation, the laying hens were successfully infected. Compared with the uninoculated group, the i.v. and oronasally inoculated groups exhibited egg production decreases at 1wpi and 2wpi, reaching peak production at 3wpi and 8wpi, respectively. In both groups, decreased production was evident for 12 weeks and overall decreases ranged from 10% to 30%. In addition, in the 7 field layer farms exhibiting decreased egg production, vaccination regimens had been completed against Newcastle disease, infectious bronchitis, avian influenza H9N2 and H5N1 and egg drop syndrome virus. However, circulating avian HEV was confirmed on these farms using tests to detect avian HEV IgG antibodies and RNA. Therefore, the experimental and field data indicate that avian HEV infection acting alone could account for observed decreases in egg production in laying hens. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Avian Influenza infections in nonmigrant land birds in Andean Peru.

    Science.gov (United States)

    Williams, Richard A J; Segovia-Hinostroza, Karen; Ghersi, Bruno M; Gonzaga, Victor; Peterson, A Townsend; Montgomery, Joel M

    2012-10-01

    As part of ongoing surveillance for avian influenza viruses (AIV) in Peruvian birds, in June 2008, we sampled 600 land birds of 177 species, using real-time reverse-transcription PCR. We addressed the assumption that AIV prevalence is low or nil among land birds, a hypodiesis that was not supported by the results-rather, we found AIV infections at relatively high prevalences in birds of the orders Apodiformes (hummingbirds) and Passeriformes (songbirds). Surveillance programs for monitoring spread and identification of AIV should thus not focus solely on water birds.

  16. Zoonotic infection with Chlamydia psittaci at an avian refuge centre.

    Science.gov (United States)

    Kalmar, Isabelle D; Dicxk, Veerle; Dossche, Liesbeth; Vanrompay, Daisy

    2014-02-01

    This paper reports the zoonotic transmission of Chlamydia psittaci at a wild bird refuge centre resulting in the infection of members of the staff. Pharyngeal swabs were culture positive in 26% (11/42) of the sampled birds, and molecular characterisation of isolates revealed genotypes A, B, D, and E/B. The finding reflects multiple distinct infections and highlights the endemic nature of this pathogen in avian wildlife. Two clinically normal birds being prepared for release were found to be excreting C. psittaci genotype B or E/B and viable genotype B was detected in pharyngeal swabs from 30% (3/10) of the human workers tested. The findings suggest there should be enhanced surveillance and control measures in place in bird rehabilitation centres in order to minimise the risk of both zoonoses and of re-introduction of infection back into wildlife populations. Copyright © 2013 Elsevier Ltd. All rights reserved.

  17. Human Infection with Avian Influenza A(H7N9) Virus - China

    Science.gov (United States)

    ... response operations Diseases Biorisk reduction Disease outbreak news Human infection with avian influenza A(H7N9) virus – ... Region (SAR) notified WHO of a laboratory-confirmed human infection with avian influenza A(H7N9) virus and ...

  18. Experimental Infections of Wild Birds with West Nile Virus

    Directory of Open Access Journals (Sweden)

    Elisa Pérez-Ramírez

    2014-02-01

    Full Text Available Avian models of West Nile virus (WNV disease have become pivotal in the study of infection pathogenesis and transmission, despite the intrinsic constraints that represents this type of experimental research that needs to be conducted in biosecurity level 3 (BSL3 facilities. This review summarizes the main achievements of WNV experimental research carried out in wild birds, highlighting advantages and limitations of this model. Viral and host factors that determine the infection outcome are analyzed in detail, as well as recent discoveries about avian immunity, viral transmission, and persistence achieved through experimental research. Studies of laboratory infections in the natural host will help to understand variations in susceptibility and reservoir competence among bird species, as well as in the epidemiological patterns found in different affected areas.

  19. Experimental Infections of Wild Birds with West Nile Virus

    Science.gov (United States)

    Pérez-Ramírez, Elisa; Llorente, Francisco; Jiménez-Clavero, Miguel Ángel

    2014-01-01

    Avian models of West Nile virus (WNV) disease have become pivotal in the study of infection pathogenesis and transmission, despite the intrinsic constraints that represents this type of experimental research that needs to be conducted in biosecurity level 3 (BSL3) facilities. This review summarizes the main achievements of WNV experimental research carried out in wild birds, highlighting advantages and limitations of this model. Viral and host factors that determine the infection outcome are analyzed in detail, as well as recent discoveries about avian immunity, viral transmission, and persistence achieved through experimental research. Studies of laboratory infections in the natural host will help to understand variations in susceptibility and reservoir competence among bird species, as well as in the epidemiological patterns found in different affected areas. PMID:24531334

  20. Experimental vaccinations for avian influenza virus including DIVA approaches

    Science.gov (United States)

    Avian influenza (AI) is a viral disease of poultry that remains an economic threat to commercial poultry throughout the world by negatively impacting animal health and trade. Strategies to control avian influenza (AI) virus are developed to prevent, manage or eradicate the virus from the country, re...

  1. Avian influenza virus directly infects human natural killer cells and inhibits cell activity.

    Science.gov (United States)

    Mao, Huawei; Liu, Yinping; Sia, Sin Fun; Peiris, J S Malik; Lau, Yu-Lung; Tu, Wenwei

    2017-04-01

    Natural killer (NK) cell is a key component of innate immunity and plays an important role in host defense against virus infection by directly destroying infected cells. Influenza is a respiratory disease transmitted in the early phase of virus infection. Evasion of host innate immunity including NK cells is critical for the virus to expand and establish a successful acute infection. Previously, we showed that human influenza H1N1 virus infects NK cells and induces cell apoptosis, as well as inhibits NK cell activity. In this study, we further demonstrated that avian influenza virus also directly targeted NK cells as an immunoevasion strategy. The avian virus infected human NK cells and induced cell apoptosis. In addition, avian influenza virion and HA protein inhibited NK cell cytotoxicity. This novel strategy has obvious advantages for avian influenza virus, allowing the virus sufficient time to expand and subsequent spread before the onset of the specific immune response. Our findings provide an important clue for the immunopathogenesis of avian influenza, and also suggest that direct targeting NK cells may be a common strategy used by both human and avian influenza viruses to evade NK cell immunity.

  2. Description of the first cryptic avian malaria parasite, Plasmodium homocircumflexum n. sp., with experimental data on its virulence and development in avian hosts and mosquitoes.

    Science.gov (United States)

    Palinauskas, Vaidas; Žiegytė, Rita; Ilgūnas, Mikas; Iezhova, Tatjana A; Bernotienė, Rasa; Bolshakov, Casimir; Valkiūnas, Gediminas

    2015-01-01

    For over 100 years studies on avian haemosporidian parasite species have relied on similarities in their morphology to establish a species concept. Some exceptional cases have also included information about the life cycle and sporogonic development. More than 50 avian Plasmodium spp. have now been described. However, PCR-based studies show a much broader diversity of haemosporidian parasites, indicating the possible existence of a diverse group of cryptic species. In the present study, using both similarity and phylogenetic species definition concepts, we believe that we report the first characterised cryptic speciation case of an avian Plasmodium parasite. We used sequence information on the mitochondrial cytochrome b gene and constructed phylogenies of identified Plasmodium spp. to define their position in the phylogenetic tree. After analysis of blood stages, the morphology of the parasite was shown to be identical to Plasmodium circumflexum. However, the geographic distribution of the new parasite, the phylogenetic information, as well as patterns of development of infection, indicate that this parasite differs from P. circumflexum. Plasmodium homocircumflexum n. sp. was described based on information about genetic differences from described lineages, phylogenetic position and biological characters. This parasite develops parasitemia in experimentally infected birds - the domestic canary Serinus canaria domestica, siskin Carduelis spinus and crossbill Loxia curvirostra. Anaemia caused by high parasitemia, as well as cerebral paralysis caused by exoerythrocytic stages in the brain, are the main reasons for mortality. Exoerythrocytic stages also form in other organs (heart, kidneys, liver, lungs, spleen, intestines and pectoral muscles). DNA amplification was unsuccessful from faecal samples of heavily infected birds. The sporogonic development initiates, but is abortive, at the oocyst stage in two common European mosquito species, Culex pipiens pipiens (forms

  3. Infections with Avian Pathogenic and Fecal Escherichia coli Strains Display Similar Lung Histopathology and Macrophage Apoptosis

    Science.gov (United States)

    Horn, Fabiana; Corrêa, André Mendes Ribeiro; Barbieri, Nicolle Lima; Glodde, Susanne; Weyrauch, Karl Dietrich; Kaspers, Bernd; Driemeier, David; Ewers, Christa; Wieler, Lothar H.

    2012-01-01

    The purpose of this study was to compare histopathological changes in the lungs of chickens infected with avian pathogenic (APEC) and avian fecal (Afecal) Escherichia coli strains, and to analyze how the interaction of the bacteria with avian macrophages relates to the outcome of the infection. Chickens were infected intratracheally with three APEC strains, MT78, IMT5155, and UEL17, and one non-pathogenic Afecal strain, IMT5104. The pathogenicity of the strains was assessed by isolating bacteria from lungs, kidneys, and spleens at 24 h post-infection (p.i.). Lungs were examined for histopathological changes at 12, 18, and 24 h p.i. Serial lung sections were stained with hematoxylin and eosin (HE), terminal deoxynucleotidyl dUTP nick end labeling (TUNEL) for detection of apoptotic cells, and an anti-O2 antibody for detection of MT78 and IMT5155. UEL17 and IMT5104 did not cause systemic infections and the extents of lung colonization were two orders of magnitude lower than for the septicemic strains MT78 and IMT5155, yet all four strains caused the same extent of inflammation in the lungs. The inflammation was localized; there were some congested areas next to unaffected areas. Only the inflamed regions became labeled with anti-O2 antibody. TUNEL labeling revealed the presence of apoptotic cells at 12 h p.i in the inflamed regions only, and before any necrotic foci could be seen. The TUNEL-positive cells were very likely dying heterophils, as evidenced by the purulent inflammation. Some of the dying cells observed in avian lungs in situ may also be macrophages, since all four avian E. coli induced caspase 3/7 activation in monolayers of HD11 avian macrophages. In summary, both pathogenic and non-pathogenic fecal strains of avian E. coli produce focal infections in the avian lung, and these are accompanied by inflammation and cell death in the infected areas. PMID:22848424

  4. Serologic evidence of avian influenza virus infections among Nigerian agricultural workers.

    Science.gov (United States)

    Okoye, John; Eze, Didacus; Krueger, Whitney S; Heil, Gary L; Friary, John A; Gray, Gregory C

    2013-04-01

    Nigeria has had multiple incursions of highly pathogenic avian influenza A (HPAI) H5N1 virus into its poultry population since 2006. This study aimed to determine if Nigerians exposed to poultry had evidence of avian influenza virus transmission to man. Between 2008 and 2010, 316 adult farmers and open market workers and 54 age-group matched, non-animal exposed controls were enrolled in a prospective, population-based study of zoonotic influenza transmission in four towns in southeastern Nigeria. Questionnaire data and sera obtained at the time of enrollment were examined for evidence of previous infection with 10 avian influenza virus strains. Serologic studies on sera collected at the time of enrollment showed modest evidence of previous infection with three avian-origin influenza viruses (H5N1, H5N2, and H11N1) and one avian-like H9N2 influenza virus, with eight (2.4%) of animal-exposed subjects and two (3.7%) unexposed subjects having elevated microneutralization assay antibody titer levels (ranging from 1:10 to 1:80). Statistical analyses did not identify specific risk factors associated with the elevated antibody titers observed for these zoonotic influenza viruses. These data suggested only occasional virus transmission to humans in areas thought to have been enzootic for avian influenza virus. Prospective data from this cohort will help the authors to better understand the occurrence of zoonotic infections due to avian influenza viruses in Nigeria. Copyright © 2013 Wiley Periodicals, Inc.

  5. Ascorbic acid inhibits replication and infectivity of avian RNA tumor virus

    Energy Technology Data Exchange (ETDEWEB)

    BISSELL, MINA J; HATIE, CARROLL; FARSON, DEBORAH A.; SCHWARZ, RICHARD I.; SOO, WHAI-JEN

    1980-04-01

    Ascorbic acid, at nontoxic concentrations, causes a substantial reduction in the ability of avian tumor viruses to replicate in both primary avian tendon cells and chicken embryo fibroblasts. The virus-infected cultures appear to be less transformed in the presence of ascorbic acid by the criteria of morphology, reduced glucose uptake, and increased collagen synthesis. The vitamin does not act by altering the susceptibility of the cells to initial infection and transformation, but instead appears to interfere with the spread of infection through a reduction in virus replication and virus infectivity. The effect is reversible and requires the continuous presence of the vitamin in the culture medium.

  6. Evidence for Avian H9N2 Influenza Virus Infections among Rural Villagers in Cambodia

    Science.gov (United States)

    Blair, Patrick J.; Putnam, Shannon D.; Krueger, Whitney S.; Chum, Channimol; Wierzba, Thomas F.; Heil, Gary L.; Yasuda, Chadwick Y.; Williams, Maya; Kasper, Matthew R.; Friary, John A.; Capuano, Ana W.; Saphonn, Vonthanak; Peiris, Malik; Shao, Hongxia; Perez, Daniel R.; Gray, Gregory C.

    2013-01-01

    Background Southeast Asia remains a critical region for the emergence of novel and/or zoonotic influenza, underscoring the importance of extensive sampling in rural areas where early transmission is most likely to occur. Methods In 2008, 800 adult participants from eight sites were enrolled in a prospective population-based study of avian influenza (AI) virus transmission where highly pathogenic avian influenza (HPAI) H5N1 virus had been reported in humans and poultry from 2006 to 2008. From their enrollment sera and questionnaires, we report risk factor findings for serologic evidence of previous infection with 18 AI virus strains. Results Serologic assays revealed no evidence of previous infection with 13 different low-pathogenic AI viruses or with HPAI avian-like A/Cambodia/R0404050/2007(H5N1). However, 21 participants had elevated antibodies against avian-like A/Hong Kong/1073/1999(H9N2), validated with a monoclonal antibody blocking ELISA assay specific for avian H9. Conclusions Although cross-reaction from antibodies against human influenza viruses cannot be completely excluded, the study data suggest that a number of participants were previously infected with the avian-like A/Hong Kong/1073/1999(H9N2) virus, likely due to as yet unidentified environmental exposures. Prospective data from this cohort will help us better understand the serology of zoonotic influenza infection in a rural cohort in SE Asia. PMID:23537819

  7. Little evidence of subclinical avian influenza virus infections among rural villagers in Cambodia.

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    Gregory C Gray

    Full Text Available In 2008, 800 adults living within rural Kampong Cham Province, Cambodia were enrolled in a prospective cohort study of zoonotic influenza transmission. After enrollment, participants were contacted weekly for 24 months to identify acute influenza-like illnesses (ILI. Follow-up sera were collected at 12 and 24 months. A transmission substudy was also conducted among the family contacts of cohort members reporting ILI who were influenza A positive. Samples were assessed using serological or molecular techniques looking for evidence of infection with human and avian influenza viruses. Over 24 months, 438 ILI investigations among 284 cohort members were conducted. One cohort member was hospitalized with a H5N1 highly pathogenic avian influenza (HPAI virus infection and withdrew from the study. Ninety-seven ILI cases (22.1% were identified as influenza A virus infections by real-time RT-PCR; none yielded evidence for AIV. During the 2 years of follow-up, 21 participants (3.0% had detectable antibody titers (≥ 1:10 against the studied AIVs: 1 against an avian-like A/Migratory duck/Hong Kong/MPS180/2003(H4N6, 3 against an avian-like A/Teal/Hong Kong/w312/97(H6N1, 9 (3 of which had detectible antibody titers at both 12- and 24-month follow-up against an avian-like A/Hong Kong/1073/1999(H9N2, 6 (1 detected at both 12- and 24-month follow-up against an avian-like A/Duck/Memphis/546/74(H11N9, and 2 against an avian-like A/Duck/Alberta/60/76(H12N5. With the exception of the one hospitalized cohort member with H5N1 infection, no other symptomatic avian influenza infections were detected among the cohort. Serological evidence for subclinical infections was sparse with only one subject showing a 4-fold rise in microneutralization titer over time against AvH12N5. In summary, despite conducting this closely monitored cohort study in a region enzootic for H5N1 HPAI, we were unable to detect subclinical avian influenza infections, suggesting either that these

  8. Experimental evidence for evolved tolerance to avian malaria in a wild population of low elevation Hawai`i `Amakihi (Hemignathus virens)

    Science.gov (United States)

    Atkinson, Carter T.; Saili, Katerine S.; Utzurrum, Ruth B.; Jarvi, Susan I.

    2013-01-01

    Introduced vector-borne diseases, particularly avian malaria (Plasmodium relictum) and avian pox virus (Avipoxvirus spp.), continue to play significant roles in the decline and extinction of native forest birds in the Hawaiian Islands. Hawaiian honeycreepers are particularly susceptible to avian malaria and have survived into this century largely because of persistence of high elevation refugia on Kaua‘i, Maui, and Hawai‘i Islands, where transmission is limited by cool temperatures. The long term stability of these refugia is increasingly threatened by warming trends associated with global climate change. Since cost effective and practical methods of vector control in many of these remote, rugged areas are lacking, adaptation through processes of natural selection may be the best long-term hope for recovery of many of these species. We document emergence of tolerance rather than resistance to avian malaria in a recent, rapidly expanding low elevation population of Hawai‘i ‘Amakihi (Hemignathus virens) on the island of Hawai‘i. Experimentally infected low elevation birds had lower mortality, lower reticulocyte counts during recovery from acute infection, lower weight loss, and no declines in food consumption relative to experimentally infected high elevation Hawai‘i ‘Amakihi in spite of similar intensities of infection. Emergence of this population provides an exceptional opportunity for determining physiological mechanisms and genetic markers associated with malaria tolerance that can be used to evaluate whether other, more threatened species have the capacity to adapt to this disease.

  9. Genome Wide Host Gene Expression Analysis in Chicken Lungs Infected with Avian Influenza Viruses.

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    Pradip B Ranaware

    Full Text Available The molecular pathogenesis of avian influenza infection varies greatly with individual bird species and virus strain. The molecular pathogenesis of the highly pathogenic avian influenza virus (HPAIV or the low pathogenic avian influenza virus (LPAIV infection in avian species remains poorly understood. Thus, global immune response of chickens infected with HPAI H5N1 (A/duck/India/02CA10/2011 and LPAI H9N2 (A/duck/India/249800/2010 viruses was studied using microarray to identify crucial host genetic components responsive to these infection. HPAI H5N1 virus induced excessive expression of type I IFNs (IFNA and IFNG, cytokines (IL1B, IL18, IL22, IL13, and IL12B, chemokines (CCL4, CCL19, CCL10, and CX3CL1 and IFN stimulated genes (OASL, MX1, RSAD2, IFITM5, IFIT5, GBP 1, and EIF2AK in lung tissues. This dysregulation of host innate immune genes may be the critical determinant of the severity and the outcome of the influenza infection in chickens. In contrast, the expression levels of most of these genes was not induced in the lungs of LPAI H9N2 virus infected chickens. This study indicated the relationship between host immune genes and their roles in pathogenesis of HPAIV infection in chickens.

  10. Transmission dynamics of low pathogenicity avian influenza infections in Turkey flocks.

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    Arianna Comin

    Full Text Available Low pathogenicity avian influenza (LPAI viruses of H5 and H7 subtypes have the potential to mutate into highly pathogenic strains (HPAI, which can threaten human health and cause huge economic losses. The current knowledge on the mechanisms of mutation from LPAI to HPAI is insufficient for predicting which H5 or H7 strains will mutate into an HPAI strain, and since the molecular changes necessary for the change in virulence seemingly occur at random, the probability of mutation depends on the number of virus replicates, which is associated with the number of birds that acquire infection. We estimated the transmission dynamics of LPAI viruses in turkeys using serosurveillance data from past epidemics in Italy. We fitted the proportions of birds infected in 36 flocks into a hierarchical model to estimate the basic reproduction number (R(0 and possible variations in R(0 among flocks caused by differences among farms. We also estimated the distributions of the latent and infectious periods, using experimental infection data with outbreak strains. These were then combined with the R(0 to simulate LPAI outbreaks and characterise the resulting dynamics. The estimated mean within-flock R(0 in the population of infected flocks was 5.5, indicating that an infectious bird would infect an average of more than five susceptible birds. The results also indicate that the presence of seropositive birds does not necessarily mean that the virus has already been cleared and the flock is no longer infective, so that seropositive flocks may still constitute a risk of infection for other flocks. In light of these results, the enforcement of appropriate restrictions, the culling of seropositive flocks, or pre-emptive slaughtering may be useful. The model and parameter estimates presented in this paper provide the first complete picture of LPAI dynamics in turkey flocks and could be used for designing a suitable surveillance program.

  11. Experimental Infection of Sheep using Infective Larvae (L3 ...

    African Journals Online (AJOL)

    Experimental Infection of Sheep using Infective Larvae (L3) harvested from the Faeces of Naturally Infected Swayne's Hartebeest ( Alcelaphus buselaphus swaynei ) at Senkele Swayne's Hartebeest Sanctuary, Ethiopia.

  12. Reproduction of hemangioma by infection with subgroup J avian leukosis virus: the vertical transmission is more hazardous than the horizontal way

    OpenAIRE

    Lin, Yan; Xia, Jing; Zhao, Yang; Wang, Fuyan; Yu, Songcheng; Zou, Nianli; Wen, Xintian; Cao, Sanjie; Huang, Yong

    2013-01-01

    Background Clinical cases of hemangioma associated with subgroup J avian leukosis virus (ALV-J) have been reported in commercial chicken layer flocks since 2006. We attempted to reproduce hemangioma through experimental infection with ALV-J to evaluate viral pathogenicity in layer birds and their progenies. Results Body weight and indexes for immune organs of chickens infected with ALV-J strain SCDY1 were lower than those in controls. Proliferation of lymphocytes was observed in many tissues,...

  13. Infections with avian pathogenic and fecal Escherichia coli strains display similar lung histopathology and macrophage apoptosis.

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    Fabiana Horn

    Full Text Available The purpose of this study was to compare histopathological changes in the lungs of chickens infected with avian pathogenic (APEC and avian fecal (A(fecal Escherichia coli strains, and to analyze how the interaction of the bacteria with avian macrophages relates to the outcome of the infection. Chickens were infected intratracheally with three APEC strains, MT78, IMT5155, and UEL17, and one non-pathogenic A(fecal strain, IMT5104. The pathogenicity of the strains was assessed by isolating bacteria from lungs, kidneys, and spleens at 24 h post-infection (p.i.. Lungs were examined for histopathological changes at 12, 18, and 24 h p.i. Serial lung sections were stained with hematoxylin and eosin (HE, terminal deoxynucleotidyl dUTP nick end labeling (TUNEL for detection of apoptotic cells, and an anti-O2 antibody for detection of MT78 and IMT5155. UEL17 and IMT5104 did not cause systemic infections and the extents of lung colonization were two orders of magnitude lower than for the septicemic strains MT78 and IMT5155, yet all four strains caused the same extent of inflammation in the lungs. The inflammation was localized; there were some congested areas next to unaffected areas. Only the inflamed regions became labeled with anti-O2 antibody. TUNEL labeling revealed the presence of apoptotic cells at 12 h p.i in the inflamed regions only, and before any necrotic foci could be seen. The TUNEL-positive cells were very likely dying heterophils, as evidenced by the purulent inflammation. Some of the dying cells observed in avian lungs in situ may also be macrophages, since all four avian E. coli induced caspase 3/7 activation in monolayers of HD11 avian macrophages. In summary, both pathogenic and non-pathogenic fecal strains of avian E. coli produce focal infections in the avian lung, and these are accompanied by inflammation and cell death in the infected areas.

  14. Experimental challenge and pathology of highly pathogenic avian influenza virus H5N1 in dunlin (Calidris alpina), an intercontinental migrant shorebird species

    Science.gov (United States)

    Hall, Jeffrey S.; Franson, J. Christian; Gill, Robert E.; Meteyer, Carol U.; TeSlaa, Joshua L.; Nashold, Sean W.; Dusek, Robert J.; Ip, Hon S.

    2011-01-01

    Background Shorebirds (Charadriiformes) are considered one of the primary reservoirs of avian influenza. Because these species are highly migratory, there is concern that infected shorebirds may be a mechanism by which highly pathogenic avian influenza virus (HPAIV) H5N1 could be introduced into North America from Asia. Large numbers of dunlin (Calidris alpina) migrate from wintering areas in central and eastern Asia, where HPAIV H5N1 is endemic, across the Bering Sea to breeding areas in Alaska. Low pathogenic avian influenza virus has been previously detected in dunlin, and thus, dunlin represent a potential risk to transport HPAIV to North America. To date no experimental challenge studies have been performed in shorebirds.

  15. Infectivity and transmissibility of highly pathogenic avian influenza viruses in mallards

    Science.gov (United States)

    Wild aquatic birds have been associated with the intercontinental spread of H5 subtype highly pathogenic avian influenza (HPAI) viruses, but wild waterfowl have not been implicated in the spread of other HPAI viruses. In a previous study we demonstrated that many H5 and H7 HPAI viruses could infect...

  16. Filter-feeding bivalves can remove avian influenza viruses from water and reduce infectivity

    Science.gov (United States)

    Avian influenza (AI) viruses are transmitted within wild aquatic bird populations through an indirect fecal-oral route involving fecal-contaminated water. In this study, the influence of filter-feeding bivalves, Corbicula fluminea, on the infectivity of AI virus in water was examined. A single cla...

  17. Transcription factor regulation and cytokine expression following in vitro infection of primary chicken cell culture with low pathogenic avian influenza virus

    Science.gov (United States)

    Avian influenza virus (AIV) induced proinflammatory cytokine expression is believed to contribute to the disease pathogenesis following infection. However, there is limited information on the avian immune response to infection with low pathogenic avian influenza virus (LPAIV). To gain a better under...

  18. Avian host-selection by Culex pipiens in experimental trials.

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    Jennifer E Simpson

    Full Text Available Evidence from field studies suggests that Culex pipiens, the primary mosquito vector of West Nile virus (WNV in the northeastern and north central United States, feeds preferentially on American robins (Turdus migratorius. To determine the contribution of innate preferences to observed preference patterns in the field, we conducted host preference trials with a known number of adult female C. pipiens in outdoor cages comparing the relative attractiveness of American robins with two common sympatric bird species, European starling, Sternus vulgaris and house sparrow, Passer domesticus. Host seeking C. pipiens were three times more likely to enter robin-baited traps when with the alternate host was a European starling (n = 4 trials; OR = 3.06; CI [1.42-6.46] and almost twice more likely when the alternative was a house sparrow (n = 8 trials; OR = 1.80; CI = [1.22-2.90]. There was no difference in the probability of trap entry when two robins were offered (n = 8 trials. Logistic regression analysis determined that the age, sex and weight of the birds, the date of the trial, starting-time, temperature, humidity, wind-speed and age of the mosquitoes had no effect on the probability of a choosing a robin over an alternate bird. Findings indicate that preferential feeding by C. pipiens mosquitoes on certain avian hosts is likely to be inherent, and we discuss the implications innate host preferences may have on enzootic WNV transmission.

  19. Avian Plasmodium infection in field-collected mosquitoes during 2012-2013 in Tarlac, Philippines.

    Science.gov (United States)

    Chen, Tien-Huang; Aure, Wilfredo E; Cruz, Estrella Irlandez; Malbas, Fedelino F; Teng, Hwa-Jen; Lu, Liang-Chen; Kim, Kyeong Soon; Tsuda, Yoshio; Shu, Pei-Yun

    2015-12-01

    Global warming threatens to increase the spread and prevalence of mosquito-transmitted diseases. Certain pathogens may be carried by migratory birds and transmitted to local mosquito populations. Mosquitoes were collected in the northern Philippines during bird migration seasons to detect avian malaria parasites as well as for the identification of potential vector species and the estimation of infections among local mosquito populations. We used the nested PCR to detect the avian malaria species. Culex vishnui (47.6%) was the most abundant species collected and Cx. tritaeniorhynchus (13.8%) was the second most abundant. Avian Plasmodium parasites were found in eight mosquito species, for which the infection rates were between 0.5% and 6.2%. The six Plasmodium genetic lineages found in this study included P. juxtanucleare -GALLUS02, Tacy7 (Donana04), CXBIT01, Plasmodium species LIN2 New Zealand, and two unclassified lineages. The potential mosquito vectors for avian Plasmodium parasites in the Philippines were Cq. crassipes, Cx. fuscocephala, Cx. quinquefasciatus, Cx. sitiens, Cx. vishnui, and Ma. Uniformis; two major genetic lineages, P. juxtanucleare and Tacy7, were identified. © 2015 The Society for Vector Ecology.

  20. Bloodmeal analysis reveals avian Plasmodium infections and broad host preferences of Culicoides (Diptera: Ceratopogonidae vectors.

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    Diego Santiago-Alarcon

    Full Text Available Changing environmental conditions and human encroachment on natural habitats bring human populations closer to novel sources of parasites, which might then develop into new emerging diseases. Diseases transmitted by host generalist vectors are of special interest due to their capacity to move pathogens into novel hosts. We hypothesize that humans using forests for recreation are exposed to a broad range of parasites from wild animals and their vectors. A corollary of this is that new vector-host, parasite-host, and vector-parasite associations could eventually develop. Thus, we expect to observe atypical vector-host associations. Using molecular bloodmeal analysis via amplification of the mtDNA COI gene we identified the vertebrate hosts of Culicoides (Diptera: Ceratopogonidae species in a sub-urban forest of Southwestern Germany. Bloodmeals were also checked for haemosporidian infections by amplifying a fragment of the mtDNA cyt b gene. We identified a total of 20 Culicoides species, thirteen of which fed on humans. From 105 screened bloodmeals we obtained high quality sequences for 77 samples, 73 (94.8% originated from humans, two from livestock (Bos taurus and Equus caballus, and two from wild birds (Sylvia atricapilla and Turdus merula. We found that four Culicoides species previously assumed to feed exclusively on either birds (C. kibunensis or domestic mammals (C. chiopterus, C. deltus, C. scoticus fed also on humans. A total of six Culicoides abdomens were infected with avian haemosporidian parasites (Plasmodium or Haemoproteus, four of those abdomens contained blood derived from humans. Our results suggest that parasites of wild animals may be transferred to humans through infectious bites of Culicoides vectors. Further, we show that Culicoides vectors believed to be a specialist on specific vertebrate groups can have plastic feeding preferences, and that Culicoides are susceptible to infection by Plasmodium parasites, though vector

  1. The chicken as a natural model for extraintestinal infections caused by avian pathogenic Escherichia coli (APEC).

    Science.gov (United States)

    Antão, Esther-Maria; Glodde, Susanne; Li, Ganwu; Sharifi, Reza; Homeier, Timo; Laturnus, Claudia; Diehl, Ines; Bethe, Astrid; Philipp, Hans-C; Preisinger, Rudolf; Wieler, Lothar H; Ewers, Christa

    2008-01-01

    E. coli infections in avian species have become an economic threat to the poultry industry worldwide. Several factors have been associated with the virulence of E. coli in avian hosts, but no specific virulence gene has been identified as being entirely responsible for the pathogenicity of avian pathogenic E. coli (APEC). Needless to say, the chicken would serve as the best model organism for unravelling the pathogenic mechanisms of APEC, an extraintestinal pathogen. Five-week-old white leghorn SPF chickens were infected intra-tracheally with a well characterized APEC field strain IMT5155 (O2:K1:H5) using different doses corresponding to the respective models of infection established, that is, the lung colonization model allowing re-isolation of bacteria only from the lung but not from other internal organs, and the systemic infection model. These two models represent the crucial steps in the pathogenesis of APEC infections, including the colonization of the lung epithelium and the spread of bacteria throughout the bloodstream. The read-out system includes a clinical score, pathomorphological changes and bacterial load determination. The lung colonization model has been established and described for the first time in this study, in addition to a comprehensive account of a systemic infection model which enables the study of severe extraintestinal pathogenic E. coli (ExPEC) infections. These in vivo models enable the application of various molecular approaches to study host-pathogen interactions more closely. The most important application of such genetic manipulation techniques is the identification of genes required for extraintestinal virulence, as well as host genes involved in immunity in vivo. The knowledge obtained from these studies serves the dual purpose of shedding light on the nature of virulence itself, as well as providing a route for rational attenuation of the pathogen for vaccine construction, a measure by which extraintestinal infections, including

  2. Avian pox infection in a free-living crested serpent eagle (Spilornis cheela) in southern Taiwan.

    Science.gov (United States)

    Chen, C C; Pei, K J C; Lee, F R; Tzeng, M P; Chang, T C

    2011-03-01

    Avian pox viruses (APVs) have been reported to cause infection in diverse avian species worldwide. Herein we report the first case of APV infection in a free-living bird, a subadult crested serpent eagle (Spilornis cheela), in Taiwan. In addition to the typical wart-like lesions distributed on the cere, eyelid, and face, there were also yellowish nodules below the tongue and on the hard palate. Phylogenetic analysis of the 4b core protein gene showed that the APV is very close to that found in white-tailed sea eagle (Haliaeetus albicilla) in Japan recently. Because both cases are located on the same major flyway for migratory birds, the impact of this virus with regard to the wild and migratory raptor species along the East Asian-Australasian Flyway and West Pacific Flyway requires immediate investigation.

  3. Identification of New World Quails Susceptible to Infection with Avian Leukosis Virus Subgroup J.

    Science.gov (United States)

    Plachý, Jiří; Reinišová, Markéta; Kučerová, Dana; Šenigl, Filip; Stepanets, Volodymyr; Hron, Tomáš; Trejbalová, Kateřina; Elleder, Daniel; Hejnar, Jiří

    2017-02-01

    The J subgroup of avian leukosis virus (ALV-J) infects domestic chickens, jungle fowl, and turkeys. This virus enters the host cell through a receptor encoded by the tvj locus and identified as Na+/H+ exchanger 1. The resistance to avian leukosis virus subgroup J in a great majority of galliform species has been explained by deletions or substitutions of the critical tryptophan 38 in the first extracellular loop of Na+/H+ exchanger 1. Because there are concerns of transspecies virus transmission, we studied natural polymorphisms and susceptibility/resistance in wild galliforms and found the presence of tryptophan 38 in four species of New World quails. The embryo fibroblasts of New World quails are susceptible to infection with avian leukosis virus subgroup J, and the cloned Na+/H+ exchanger 1 confers susceptibility on the otherwise resistant host. New World quails are also susceptible to new avian leukosis virus subgroup J variants but resistant to subgroups A and B and weakly susceptible to subgroups C and D of avian sarcoma/leukosis virus due to obvious defects of the respective receptors. Our results suggest that the avian leukosis virus subgroup J could be transmitted to New World quails and establish a natural reservoir of circulating virus with a potential for further evolution. Since its spread in broiler chickens in China and Southeast Asia in 2000, ALV-J remains a major enzootic challenge for the poultry industry. Although the virus diversifies rapidly in the poultry, its spillover and circulation in wild bird species has been prevented by the resistance of most species to ALV-J. It is, nevertheless, important to understand the evolution of the virus and its potential host range in wild birds. Because resistance to avian retroviruses is due particularly to receptor incompatibility, we studied Na+/H+ exchanger 1, the receptor for ALV-J. In New World quails, we found a receptor compatible with virus entry, and we confirmed the susceptibilities of four New

  4. Expression of Immune-Related Genes of Ducks Infected with Avian Pathogenic Escherichia coli (APEC).

    Science.gov (United States)

    Li, Rong; Li, Ning; Zhang, Jinzhou; Wang, Yao; Liu, Jiyuan; Cai, Yumei; Chai, Tongjie; Wei, Liangmeng

    2016-01-01

    Avian pathogenic Escherichia coli (APEC) can cause severe disease in ducks, characterized by perihepatitis, pericarditis, and airsacculitis. Although the studies of bacteria isolation and methods of detection have been reported, host immune responses to APEC infection remain unclear. In response, we systemically examined the expression of immune-related genes and bacteria distribution in APEC-infected ducks. Results demonstrated that APEC can quickly replicate in the liver, spleen, and brain, with the highest bacteria content at 2 days post infection. The expression of toll-like receptors (TLRs), avian β-defensins (AvBDs) and major histocompatibility complex (MHC) were tested in the liver, spleen, and brain of infected ducks. TLR2, TLR4, TLR5, and TLR15 showed different expression patterns, which indicated that they all responded to APEC infection. The expression of AvBD2 was upregulated in all tested tissues during the 3 days of testing, whereas the expression of AvBD4, AvBD5, AvBD7, and AvBD9 were downregulated, and though MHC-I was upregulated on all test days, MHC-II was dramatically downregulated. Overall, our results suggest that APEC can replicate in various tissues in a short time, and the activation of host immune responses begins at onset of infection. These findings thus clarify duck immune responses to APEC infection and offer insights into its pathogenesis.

  5. Expression of Immune-Related Genes of Ducks Infected with Avian Pathogenic Escherichia coli (APEC

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    Rong eLi

    2016-05-01

    Full Text Available Avian pathogenic Escherichia coli (APEC can cause severe disease in ducks, characterized by perihepatitis, pericarditis and airsacculitis. Although the studies of bacteria isolation and methods of detection have been reported, host immune responses to APEC infection remain unclear. In response, we systemically examined the expression of immune-related genes and bacteria distribution in APEC-infected ducks. Results demonstrated that APEC can quickly replicate in the liver, spleen and brain, with the highest bacteria content at 2 day post infection. The expression of Toll-like receptors (TLRs, avian β-defensins (AvBDs and major histocompatibility complex (MHC were tested in the liver, spleen and brain of infected ducks. TLR2, TLR4, TLR5 and TLR15 showed different expression patterns, which indicated that they all responded to APEC infection. The expression of AvBD2 was upregulated in all tested tissues during the 3 days of testing, whereas the expression of AvBD4, AvBD5, AvBD7 and AvBD9 were downregulated, and though MHC-I was upregulated on all test days, MHC-II was dramatically downregulated. Overall, our results suggest that APEC can replicate in various tissues in a short time, and the activation of host immune responses begins at onset of infection. These findings thus clarify duck immune responses to APEC infection and offer insights into its pathogenesis.

  6. Experimental Trichomonas infection: Morphological aspects

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    E. N. Shumkova

    2016-01-01

    Full Text Available Background. Growth tendency the asymptomatic forms of an urogenital trichomoniasis, frequency of complications from reproductive organs, uncertainty of many aspects of the violations of a spermatogenesis influencing reproductive function all this proves need of search of the urogenital trichomoniasis adequate experimental model. Lack of the corresponding experimental model is limited by our opportunities for carrying out the standardized, controlled researches on studying of transmission, pathogenesis, the immune answer, therapy and development of vaccines at a triсhomonas infection.Objective is studying action of Trichomonas vaginalis on a spermatogenny epithelium the mature of individuals of guinea pigs in the conditions of sharp and chronic experience.Materials and methods. Experiments are made on the “Reproductive System (Guinea Pigs + Trichomonas vaginalis” modeling the natural course of an infection. In experiment 2 groups of animals: 1st (n = 8 – experimental, 2nd (n = 8 – control were formed. Against the background of the reduction of the immune status (hydrocortisone 125 mg/kg intramuscularly 1 time in day during 2 days the animals of the 1st group were injected intraurethral suspension containing 1 × 106 Trichomonas on 0.5 ml of culture medium, the animals of the 2nd group – 0.5 ml of medium. Under the condition of the acute experiment the animals were sacrificed on day 9 (the middle of the cycle of spermatogenesis – I experienced group and on day 30 (full spermatogenic cycle – II experimental group. The control animals were slaughtered in the same period. The material for histological study was prepared by the traditional way.Results. In an experimental model of “Reproductive system (guinea pigs + T. vaginalis”, staging and degree of disturbance of spermatogenesis, depending on the duration of trichomonas infection were shown. So, in acute experience morphological changes correspond to changes in the

  7. Studies on avian malaria in vectors and hosts of encephalitis in Kern County, California. I. Infections in avian hosts

    Science.gov (United States)

    Herman, C.M.; Reeves, W.C.; McClure, H.E.; French, E.M.; Hammon, W.M.

    1954-01-01

    ranged from 64 to 100 per cent in the house finch and 17 to 68 per cent in the English sparrow in different areas and years. Marked differences were found in the prevalence rates in different summer months, years and areas. It is believed these differences reflect variation in a number of environmental factors. This study indicates the extensive distribution of Plasmodium infection in a wide range of wild avian hosts. The observations are of possible importance in epidemiological studies of other arthropod-borne diseases such as the viral encephalitides for which these birds serve as hosts.

  8. Method matters: Experimental evidence for shorter avian sperm in faecal compared to abdominal massage samples.

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    Antje Girndt

    Full Text Available Birds are model organisms in sperm biology. Previous work in zebra finches, suggested that sperm sampled from males' faeces and ejaculates do not differ in size. Here, we tested this assumption in a captive population of house sparrows, Passer domesticus. We compared sperm length in samples from three collection techniques: female dummy, faecal and abdominal massage samples. We found that sperm were significantly shorter in faecal than abdominal massage samples, which was explained by shorter heads and midpieces, but not flagella. This result might indicate that faecal sampled sperm could be less mature than sperm collected by abdominal massage. The female dummy method resulted in an insufficient number of experimental ejaculates because most males ignored it. In light of these results, we recommend using abdominal massage as a preferred method for avian sperm sampling. Where avian sperm cannot be collected by abdominal massage alone, we advise controlling for sperm sampling protocol statistically.

  9. Effects of avian cholera on survival of Lesser Snow geese Anser caerulescens: An experimental approach

    Science.gov (United States)

    Samuel, Michael D.; Takekawa, John Y.; Baranyuk, Vasily V.; Orthmeyer, Dennis L.

    1999-01-01

    Avian cholera, caused by the bacterium Pasteurella multocida, is one of the most important diseases affecting waterfowl in North America but little is known about the epizootiology of this disease or its impacts on annual survival rates. We ringed Lesser Snow Geese Anser caerulescens nesting at Wrangel Island, Russia and Banks Island, Canada with metal rings and individually coded plastic neck-collars or radio-transmitters to determine survival, movement and cause of death. We vaccinated half of the neck-collared and radiotagged geese to provide protection from avian cholera for up to one year following ringing and thus experimentally determine the impacts of this disease on survival. We found that vaccination did not reduce short-term survival of the experimental birds, compared with control geese. Neck-collared geese vaccinated in 1993 at Wrangel Island had higher survival during winter 1993–94 than control birds. In contrast, we found similar survival during winter 1994–95 between vaccinated and control geese neck-collared in 1994 at Wrangel and Banks Islands. Survival of radiotagged geese on wintering areas during 1994–95 was consistent with the vaccination versus control results for neck-collared geese during the same winter. However, we found that radiotagged geese that were vaccinated had better survival than control geese during winter 1995–96. We believe that harvest and avian cholera are the two principal causes of mortality for Lesser Snow Geese wintering in the Pacific Flyway and that avian cholera may be one of the factors affecting these populations.

  10. In ovo and in vitro susceptibility of American alligators (Alligator mississippiensis) to avian influenza virus infection.

    Science.gov (United States)

    Temple, Bradley L; Finger, John W; Jones, Cheryl A; Gabbard, Jon D; Jelesijevic, Tomislav; Uhl, Elizabeth W; Hogan, Robert J; Glenn, Travis C; Tompkins, S Mark

    2015-01-01

    Avian influenza has emerged as one of the most ubiquitous viruses within our biosphere. Wild aquatic birds are believed to be the primary reservoir of all influenza viruses; however, the spillover of H5N1 highly pathogenic avian influenza (HPAI) and the recent swine-origin pandemic H1N1 viruses have sparked increased interest in identifying and understanding which and how many species can be infected. Moreover, novel influenza virus sequences were recently isolated from New World bats. Crocodilians have a slow rate of molecular evolution and are the sister group to birds; thus they are a logical reptilian group to explore susceptibility to influenza virus infection and they provide a link between birds and mammals. A primary American alligator (Alligator mississippiensis) cell line, and embryos, were infected with four, low pathogenic avian influenza (LPAI) strains to assess susceptibility to infection. Embryonated alligator eggs supported virus replication, as evidenced by the influenza virus M gene and infectious virus detected in allantoic fluid and by virus antigen staining in embryo tissues. Primary alligator cells were also inoculated with the LPAI viruses and showed susceptibility based upon antigen staining; however, the requirement for trypsin to support replication in cell culture limited replication. To assess influenza virus replication in culture, primary alligator cells were inoculated with H1N1 human influenza or H5N1 HPAI viruses that replicate independent of trypsin. Both viruses replicated efficiently in culture, even at the 30 C temperature preferred by the alligator cells. This research demonstrates the ability of wild-type influenza viruses to infect and replicate within two crocodilian substrates and suggests the need for further research to assess crocodilians as a species potentially susceptible to influenza virus infection.

  11. Avian influenza H9N2 subtype in Poland--characterization of the isolates and evidence of concomitant infections.

    Science.gov (United States)

    Smietanka, Krzysztof; Minta, Zenon; Swiętoń, Edyta; Olszewska, Monika; Jóźwiak, Michał; Domańska-Blicharz, Katarzyna; Wyrostek, Krzysztof; Tomczyk, Grzegorz; Pikuła, Anna

    2014-01-01

    In April/May 2013, four outbreaks of avian influenza virus (AIV) infections caused by H9N2 subtype were diagnosed in Poland in fattening turkey flocks exhibiting a drop in feed and water intake, depression, respiratory signs and mortality. The subsequent serological survey carried out on samples collected between June 2012 and September 2013 from 92 poultry flocks detected positive sera in two additional meat turkey flocks located in the same province. The analysis of amino acids in the haemagglutinin and neuraminidase glycoproteins revealed that the detected H9N2 viruses possessed molecular profiles suggestive of low pathogenicity, avian-like SAα2,3 receptor specificity and adaptation to domestic poultry. Phylogenetic studies showed that these H9N2 AIVs grouped within the Eurasian clade of wild bird-origin AIVs and had no relationship with H9N2 AIV circulating in poultry in the Middle East and Far East Asia over the past decade. Experimentally infected SPF chickens with the index-case H9N2 virus remained healthy throughout the experiment. On the other hand, ten 3-week-old commercial turkeys infected via the oculonasal route showed respiratory signs and mortality (2/10 birds). Additional diagnostic tests demonstrated the consistent presence of DNA/RNA of Ornithobacterium rhinotracheale, Bordetella avium and, less frequently, of astro-, rota-, reo-, parvo- and adenoviruses in turkeys both from field outbreaks and laboratory experiment. Although no microbiological culture was performed, we speculate that these secondary pathogens could play a role in the pathogenicity of the current H9N2 infections.

  12. Diverse uses of feathers with emphasis on diagnosis of avian viral infections and vaccine virus monitoring

    Directory of Open Access Journals (Sweden)

    I Davidson

    2009-09-01

    Full Text Available The large amounts of feathers produced by the poultry industry, that is considered as a waste was explored for possible uses in various industries, such as meals for animals, biofuels, biodegradable plastic materials, combating water pollution and more. That review mentions these uses, but concentrate on the utilization of feathers for the diagnosis of viral infections and for monitoring vaccine viruses in chickens after vaccination. The viral diseases in which diagnosis using nucleic acids extracted from the feather shafts was described are, Marek's disease virus, circoviruses, chicken anemia virus, fowlpox virus, avian retroviruses, avian influenza virus and infectious laryngotracheitis virus. In two cases, of Marek's disease virus and of infectious laryngotracheitis virus, the differentiation of vaccine and wild-type viruses from feather shafts was made possible, thus allowing for monitoring the vaccination efficacy. The present review demonstrates also the stability of DNA viruses in feather shafts, and the possible evaluation of environmental dissemination of pathogens. When viruses are transmitted vertically, like in the cases of the retrovirus REV, a teratogenic effect on the development of feathers of the day-old newly hatched chick might occur in the case of avian influenza and the chicken anemia virus, which might indicate on a viral infection.

  13. Differential lung NK cell responses in avian influenza virus infected chickens correlate with pathogenicity.

    Science.gov (United States)

    Jansen, Christine A; de Geus, Eveline D; van Haarlem, Daphne A; van de Haar, Peter M; Löndt, Brandon Z; Graham, Simon P; Göbel, Thomas W; van Eden, Willem; Brookes, Sharon M; Vervelde, Lonneke

    2013-01-01

    Infection of chickens with low pathogenicity avian influenza (LPAI) virus results in mild clinical signs while infection with highly pathogenic avian influenza (HPAI) viruses causes death of the birds within 36-48 hours. Since natural killer (NK) cells have been shown to play an important role in influenza-specific immunity, we hypothesise that NK cells are involved in this difference in pathogenicity. To investigate this, the role of chicken NK-cells in LPAI virus infection was studied. Next activation of lung NK cells upon HPAI virus infection was analysed. Infection with a H9N2 LPAI virus resulted in the presence of viral RNA in the lungs which coincided with enhanced activation of lung NK cells. The presence of H5N1 viruses, measured by detection of viral RNA, did not induce activation of lung NK cells. This suggests that decreased NK-cell activation may be one of the mechanisms associated with the enhanced pathogenicity of H5N1 viruses.

  14. Virus-neutralizing antibody response of mice to consecutive infection with human and avian influenza A viruses.

    Science.gov (United States)

    Janulíková, J; Stropkovská, A; Bobišová, Z; Košík, I; Mucha, V; Kostolanský, F; Varečková, E

    2015-06-01

    In this work we simulated in a mouse model a naturally occurring situation of humans, who overcame an infection with epidemic strains of influenza A, and were subsequently exposed to avian influenza A viruses (IAV). The antibody response to avian IAV in mice previously infected with human IAV was analyzed. We used two avian IAV (A/Duck/Czechoslovakia/1956 (H4N6) and the attenuated virus rA/Viet Nam/1203-2004 (H5N1)) as well as two human IAV isolates (virus A/Mississippi/1/1985 (H3N2) of medium virulence and A/Puerto Rico/8/1934 (H1N1) of high virulence). Two repeated doses of IAV of H4 or of H5 virus elicited virus-specific neutralizing antibodies in mice. Exposure of animals previously infected with human IAV (of H3 or H1 subtype) to IAV of H4 subtype led to the production of antibodies neutralizing H4 virus in a level comparable with the level of antibodies against the human IAV used for primary infection. In contrast, no measurable levels of virus-neutralizing (VN) antibodies specific to H5 virus were detected in mice infected with H5 virus following a previous infection with human IAV. In both cases the secondary infection with avian IAV led to a significant increase of the titer of VN antibodies specific to the corresponding human virus used for primary infection. Moreover, cross-reactive HA2-specific antibodies were also induced by sequential infection. By virtue of these results we suggest that the differences in the ability of avian IAV to induce specific antibodies inhibiting virus replication after previous infection of mice with human viruses can have an impact on the interspecies transmission and spread of avian IAV in the human population.

  15. Minor differences in body condition and immune status between avian influenza virus infected and non-infected mallards: a sign of co-evolution?

    NARCIS (Netherlands)

    Van Dijk, J.G.B.; Fouchier, R.A.M; Klaassen, M.R.J.; Matson, K.D.

    2015-01-01

    Wildlife pathogens can alter host fitness. Low pathogenic avian influenza virus (LPAIV) infection is thought to have negligible impacts on wild birds; however, effects of infection in free-living birds are largely unstudied. We investigated the extent to which LPAIV infection and shedding were

  16. Draft Genome Sequences of Four Salmonella enterica subsp. enterica Serovar Enteritidis Strains Implicated in Infections of Avian and Human Hosts

    KAUST Repository

    An, Ran

    2018-01-24

    Salmonella enterica subsp. enterica serovar Enteritidis is a wide-host-range pathogen. Occasionally, it is involved in invasive infections, leading to a high mortality rate. Here, we present the draft genome sequences of four S Enteritidis strains obtained from human and avian hosts that had been involved in bacteremia, gastroenteritis, and primary infections.

  17. Avian Adenoviruses Infections with Special Attention to Inclusion Body Hepatitis/ Hydropericardium Syndrome and Egg Drop Syndrome

    Directory of Open Access Journals (Sweden)

    Hafez Mohamed Hafez*

    2011-04-01

    Full Text Available The first avian adenovirus (AAV associated with clinical disease was isolated from an outbreak of respiratory disease in quail in 1950 (Olson, 1950. Since that time, AAVs have been found in all types and breeds of chickens and from a variety of other avian species. The infections may be asymptomatic or associated with several clinical and pathological conditions. Vertical transmission via the egg is the most common way of transmission. Also horizontal transmission through faeces, contaminated egg trays, crates and trucks play a role in the infection route. Studies have demonstrated the presence of antibodies in healthy poultry, and viruses have been isolated from normal birds. Avian adenoviruses in chickens are the etiological agents of 2 diseases known as inclusion body hepatitis (IBH and hydropericardium syndrome (HP. In some cases each condition is observed separately, however, recently the 2 conditions have frequently been observed as a single entity; therefore, the name hepatitis hydropericardium has been widely used to describe the pathologic condition. The syndrome is an acute disease of young chickens associated with anemia, haemorrhagic disorders, hydropericardium and high mortality. Egg-Drop-Syndrome (EDS is caused also by an adenovirus. The disease is characterised by a severe drop in egg production as well as the production of shell-less, thin-shelled, discoloured or misshapen eggs in apparently healthy birds. Ducks and geese are the natural host of the EDS virus. It was first described in chickens in the 1970s and spread to several countries world wide. The birds usually do not show any other signs of disease, and mortality is not expected. There is no specific treatment of the AAV infections. Active immunization by vaccination using an inactivated is wide spread.

  18. Proteomic analysis of Ascaridia galli. Identification of immunoreactive proteins in naturally and experimentally infected hens.

    Science.gov (United States)

    González-Miguel, Javier; Marcos-Atxutegi, Cristina; de Castello, Roberta Bottari; Carpani, Sara; Morchón, Rodrigo; Simón, Fernando

    2013-09-23

    Ascaridia galli, intestinal parasite of domestic fowl, is responsible of economic losses in avian exploitations. However, molecular mechanisms that govern avian ascaridiasis remain largely unknown. The aim of the present work was to identify proteins of A. galli recognized by the immune system of naturally and experimentally infected hens, using two-dimensional electrophoresis (2-DE) and mass spectrometry (MS). Sixteen immunoreactive proteins of A. galli were identified. These proteins are mainly related to different metabolic processes, cell motility and binding activities. The timing evolution of this recognition pattern was studied using serum samples from experimentally infected hens, allowing us to observe an early recognition of many of these antigens. Many of them were isoforms from lipid and plasminogen-binding proteins. Moreover, plasminogen-binding activity has been related in other parasites with the facilitation of intra-organic migration, which represents an important fact in avian ascaridiasis. This work represents the first proteomic study of A. galli and could contribute to explain some aspects of parasite/host relationships of avian ascaridiasis. Copyright © 2013 Elsevier B.V. All rights reserved.

  19. Experimental Ascaris suum infection in Yankasa lambs ...

    African Journals Online (AJOL)

    The effects of experimental Ascaris suum infection in Yankasa lambs were investigated. Twenty four (24) Yankasa lambs aged 6-8 months were purchased and randomly divided into two groups (1 and 2). The lambs in group 1, consisting of 16 animals, were orally infected with 1500 infective A. suum eggs daily for seven ...

  20. Avian pathogenic Escherichia coli (APEC) infection alters bone marrow transcriptome in chickens.

    Science.gov (United States)

    Sun, Hongyan; Liu, Peng; Nolan, Lisa K; Lamont, Susan J

    2015-09-15

    Avian pathogenic Escherichia coli (APEC) is a major cause of disease impacting animal health. The bone marrow is the reservoir of immature immune cells; however, it has not been examined to date for gene expression related to developmental changes (cell differentiation, maturation, programming) after APEC infection. Here, we study gene expression in the bone marrow between infected and non-infected animals, and between infected animals with mild (resistant) versus severe (susceptible) pathology, at two times post-infection. We sequenced 24 bone marrow RNA libraries generated from the six different treatment groups with four replicates each, and obtained an average of 22 million single-end, 100-bp reads per library. Genes were detected as differentially expressed (DE) between APEC treatments (mild pathology, severe pathology, and mock-challenged) at a given time point, or DE between 1 and 5 days post-infection (dpi) within the same treatment group. Results demonstrate that many immune cells, genes and related pathways are key contributors to the different responses to APEC infection between susceptible and resistant birds and between susceptible and non-challenged birds, at both times post-infection. In susceptible birds, lymphocyte differentiation, proliferation, and maturation were greatly impaired, while the innate and adaptive immune responses, including dendritic cells, monocytes and killer cell activity, TLR- and NOD-like receptor signaling, as well as T helper cells and many cytokine activities, were markedly enhanced. The resistant birds' immune system, however, was similar to that of non-challenged birds. The DE genes in the immune cells and identified signaling models are representative of activation and resolution of infection in susceptible birds at both post-infection days. These novel results characterizing transcriptomic response to APEC infection reveal that there is combinatorial activity of multiple genes controlling myeloid cells, and B and T cell

  1. Generation of influenza virus from avian cells infected by Salmonella carrying the viral genome.

    Science.gov (United States)

    Zhang, Xiangmin; Kong, Wei; Wanda, Soo-Young; Xin, Wei; Alamuri, Praveen; Curtiss, Roy

    2015-01-01

    Domestic poultry serve as intermediates for transmission of influenza A virus from the wild aquatic bird reservoir to humans, resulting in influenza outbreaks in poultry and potential epidemics/pandemics among human beings. To combat emerging avian influenza virus, an inexpensive, heat-stable, and orally administered influenza vaccine would be useful to vaccinate large commercial poultry flocks and even migratory birds. Our hypothesized vaccine is a recombinant attenuated bacterial strain able to mediate production of attenuated influenza virus in vivo to induce protective immunity against influenza. Here we report the feasibility and technical limitations toward such an ideal vaccine based on our exploratory study. Five 8-unit plasmids carrying a chloramphenicol resistance gene or free of an antibiotic resistance marker were constructed. Influenza virus was successfully generated in avian cells transfected by each of the plasmids. The Salmonella carrier was engineered to allow stable maintenance and conditional release of the 8-unit plasmid into the avian cells for recovery of influenza virus. Influenza A virus up to 10⁷ 50% tissue culture infective doses (TCID50)/ml were recovered from 11 out of 26 co-cultures of chicken embryonic fibroblasts (CEF) and Madin-Darby canine kidney (MDCK) cells upon infection by the recombinant Salmonella carrying the 8-unit plasmid. Our data prove that a bacterial carrier can mediate generation of influenza virus by delivering its DNA cargoes into permissive host cells. Although we have made progress in developing this Salmonella influenza virus vaccine delivery system, further improvements are necessary to achieve efficient virus production, especially in vivo.

  2. Generation of influenza virus from avian cells infected by Salmonella carrying the viral genome.

    Directory of Open Access Journals (Sweden)

    Xiangmin Zhang

    Full Text Available Domestic poultry serve as intermediates for transmission of influenza A virus from the wild aquatic bird reservoir to humans, resulting in influenza outbreaks in poultry and potential epidemics/pandemics among human beings. To combat emerging avian influenza virus, an inexpensive, heat-stable, and orally administered influenza vaccine would be useful to vaccinate large commercial poultry flocks and even migratory birds. Our hypothesized vaccine is a recombinant attenuated bacterial strain able to mediate production of attenuated influenza virus in vivo to induce protective immunity against influenza. Here we report the feasibility and technical limitations toward such an ideal vaccine based on our exploratory study. Five 8-unit plasmids carrying a chloramphenicol resistance gene or free of an antibiotic resistance marker were constructed. Influenza virus was successfully generated in avian cells transfected by each of the plasmids. The Salmonella carrier was engineered to allow stable maintenance and conditional release of the 8-unit plasmid into the avian cells for recovery of influenza virus. Influenza A virus up to 10⁷ 50% tissue culture infective doses (TCID50/ml were recovered from 11 out of 26 co-cultures of chicken embryonic fibroblasts (CEF and Madin-Darby canine kidney (MDCK cells upon infection by the recombinant Salmonella carrying the 8-unit plasmid. Our data prove that a bacterial carrier can mediate generation of influenza virus by delivering its DNA cargoes into permissive host cells. Although we have made progress in developing this Salmonella influenza virus vaccine delivery system, further improvements are necessary to achieve efficient virus production, especially in vivo.

  3. Immune reaction and survivability of salmonella typhimurium and salmonella infantis after infection of primary avian macrophages.

    Directory of Open Access Journals (Sweden)

    Maria Braukmann

    Full Text Available Salmonella serovars are differentially able to infect chickens. The underlying causes are not yet fully understood. Aim of the present study was to elucidate the importance of Salmonella Pathogenicity Island 1 and 2 (SPI-1 and -2 for the virulence of two non-host-specific, but in-vivo differently invasive, Salmonella serovars in conjunction with the immune reaction of the host. Primary avian splenic macrophages were inoculated with Salmonella enterica sub-species enterica serovar (S. Typhimurium and S. Infantis. The number and viability of intracellular bacteria and transcription of SPI-1 and -2 genes by the pathogens, as well as transcription of immune-related proteins, surface antigen expression and nitric oxide production by the macrophages, were compared at different times post inoculation. After infection, both of the Salmonella serovars were found inside the primary macrophages. Invasion-associated SPI-1 genes were significantly higher transcribed in S. Infantis- than S. Typhimurium-infected macrophages. The macrophages counteracted the S. Infantis and S. Typhimurium infection with elevated mRNA expression of inducible nitric oxide synthase (iNOS, interleukin (IL-12, IL-18 and lipopolysaccharide-induced tumor necrosis factor alpha factor (LITAF as well as with an increased synthesis of nitric oxide. Despite these host cell attacks, S. Typhimurium was better able than S. Infantis to survive within the macrophages and transcribed higher rates of the SPI-2 genes spiC, ssaV, sifA, and sseA. The results showed similar immune reactions of primary macrophages after infection with both of the Salmonella strains. The more rapid and stronger transcription of SPI-2-related genes by intracellular S. Typhimurium compared to S. Infantis might be responsible for its better survival in avian primary macrophages.

  4. Pathological alterations in respiratory system during co-infection with low pathogenic avian influenza virus (H9N2 and Escherichia coli in broiler chickens

    Directory of Open Access Journals (Sweden)

    Jaleel Shahid

    2017-09-01

    Full Text Available Introduction: Despite the advancements in the field, there is a lack of data when it comes to co-infections in poultry. Therefore, this study was designed to address this issue. Material and Methods: Broiler birds were experimentally infected with E. coli (O78 and low pathogenic avian influenza (LPAI strain, alone or in combination. The experimental groups were negative control. Results: The infected birds showed most severe clinical signs in E. coli+LPAI group along with a significant decrease in weight and enhanced macroscopic and microscopic pathological lesions. The survival rate was 60%, 84%, and 100% in birds inoculated with E. coli+LPAI, E. coli, and LPAI virus alone, respectively. The results showed that experimental co-infection with E. coli and H9N2 strain of LPAI virus increased the severity of clinical signs, mortality rate, and gross lesions. The HI titre against LPAI virus infection in the co-infected group was significantly higher than the HI titre of LPAI group, which may indicate that E. coli may promote propagation of H9N2 LPAI virus by alteration of immune response. Conclusion: The present study revealed that co-infection with E. coli and H9N2 LPAI virus caused more serious synergistic pathogenic effects and indicates the role of both pathogens as complicating factors in poultry infections.

  5. Taishan Pinus massoniana pollen polysaccharide inhibits subgroup J avian leucosis virus infection by directly blocking virus infection and improving immunity.

    Science.gov (United States)

    Yu, Cuilian; Wei, Kai; Liu, Liping; Yang, Shifa; Hu, Liping; Zhao, Peng; Meng, Xiuyan; Shao, Mingxu; Wang, Chuanwen; Zhu, Lijun; Zhang, Hao; Li, Yang; Zhu, Ruiliang

    2017-03-13

    Subgroup J avian leucosis virus (ALV-J) generally causes neoplastic diseases, immunosuppression and subsequently increases susceptibility to secondary infection in birds. The spread of ALV-J mainly depends on congenital infection and horizontal contact. Although ALV-J infection causes enormous losses yearly in the poultry industry worldwide, effective measures to control ALV-J remain lacking. In this study, we demonstrated that Taishan Pinus massoniana pollen polysaccharide (TPPPS), a natural polysaccharide extracted from Taishan Pinus massoniana pollen, can significantly inhibit ALV-J replication in vitro by blocking viral adsorption to host cells. Electron microscopy and blocking ELISA tests revealed that TPPPS possibly blocks viral adsorption to host cells by interacting with the glycoprotein 85 protein of ALV-J. Furthermore, we artificially established a congenitally ALV-J-infected chicken model to examine the anti-viral effects of TPPPS in vivo. TPPPS significantly inhibited viral shedding and viral loads in immune organs and largely eliminated the immunosuppression caused by congenital ALV-J infection. Additionally, pre-administration of TPPPS obviously reduced the size and delayed the occurrence of tumors induced by acute oncogenic ALV-J infection. This study revealed the prominent effects and feasible mechanisms of TPPPS in inhibiting ALV-J infection, thereby providing a novel prospect to control ALV-J spread.

  6. Mortality and pathology in birds due to Plasmodium (Giovannolaia) homocircumflexum infection, with emphasis on the exoerythrocytic development of avian malaria parasites.

    Science.gov (United States)

    Ilgūnas, Mikas; Bukauskaitė, Dovilė; Palinauskas, Vaidas; Iezhova, Tatjana A; Dinhopl, Nora; Nedorost, Nora; Weissenbacher-Lang, Christiane; Weissenböck, Herbert; Valkiūnas, Gediminas

    2016-05-04

    Species of avian malaria parasites (Plasmodium) are widespread, but their virulence has been insufficiently investigated, particularly in wild birds. During avian malaria, several cycles of tissue merogony occur, and many Plasmodium spp. produce secondary exoerythrocytic meronts (phanerozoites), which are induced by merozoites developing in erythrocytic meronts. Phanerozoites markedly damage organs, but remain insufficiently investigated in the majority of described Plasmodium spp. Avian malaria parasite Plasmodium (Giovannolaia) homocircumflexum (lineage pCOLL4) is virulent and produces phanerozoites in domestic canaries Serinus canaria, but its pathogenicity in wild birds remains unknown. The aim of this study was to investigate the pathology caused by this infection in species of common European birds. One individual of Eurasian siskin Carduelis spinus, common crossbill Loxia curvirostra and common starling Sturnus vulgaris were exposed to P. homocircumflexum infection by intramuscular sub-inoculation of infected blood. The birds were maintained in captivity and parasitaemia was monitored until their death due to malaria. Brain, heart, lungs, liver, spleen, kidney, and a piece of breast muscle were examined using histology and chromogenic in situ hybridization (ISH) methods. All exposed birds developed malaria infection, survived the peak of parasitaemia, but suddenly died between 30 and 38 days post exposure when parasitaemia markedly decreased. Numerous phanerozoites were visible in histological sections of all organs and were particularly easily visualized after ISH processing. Blockage of brain capillaries with phanerozoites may have led to cerebral ischaemia, causing cerebral paralysis and is most likely the main reason of sudden death of all infected individuals. Inflammatory response was not visible around the brain, heart and muscle phanerozoites, and it was mild in parenchymal organs. The endothelial damage likely causes dysfunction and failure of

  7. Factors influencing the severity of Escherichia coli and avian adenovirus group II infections in chickens.

    Science.gov (United States)

    Gross, W B; Domermuth, C H

    1988-01-01

    Chickens from lines selectively bred for either a high (HH) or low (LL) antibody response to sheep erythrocytes were challenged intravenously with avian adenovirus group II (AA). Spleen size was determined 6 days later. In some experiments the responses of chickens to AA and Escherichia coli infections were compared. The level of corticosterone in the feed (15 mg/kg) which resulted in the lowest incidence of pericarditis in response to E. coli resulted in the greatest incidence of large spleens in response to AA infection. Incidence of enlarged spleens in response to AA infection was increased in fasted chickens and reduced in socialized LL-line chickens. Among ignored chickens harshly treated for 2 weeks before challenge, LL-line chickens had a higher incidence of enlarged spleens than HH-line chickens. Socialized HH-line chickens subjected to social stress 1 day before challenge had more severely affected spleens than socialized LL-line chickens. The HL cross was more severely affected by AA than the LH cross but was less severely affected by E. coli. Antibody responsiveness to sheep erythrocytes did not affect the severity of AA infection. Factors that increased the severity of AA infection seemed to result in a decreased severity of E. coli infection.

  8. Radiological description about the globally first case of human infected avian influenza virus (H10N8 induced pneumonia

    Directory of Open Access Journals (Sweden)

    Jian He

    2016-03-01

    Full Text Available Human infected avian influenza (H10N8 is an acute infectious respiratory tract infection caused by JX346-H10N8. The reported case in this paper is the globally first case report about radiological description of human infected avian influenza (H10N8 virus related pneumonia. The patient showed an epidemiological history of contacts to living poultries and the incubation period lasted for 4 days. The condition was clinically characterized by fever, cough, chest distress and obvious hypoxia. CT scan demonstrated the lungs with large flake of hyper-intense consolidation, confined patch of ground glass opacity, dilated bronchi, predominantly dorsal thickening of the interlobular septum, and other types of lesions related to interstitial pulmonary edema. Meanwhile, accompanying interlobar effusion, infrapulmonary effusion and pleural effusion were demonstrated in a small quantity by CT scan. Human infected avian influenza (H10N8 related pneumonia should be differentiated from pneumonia induced by human infected avian influenza viruses H5N1 and H7N9. No characteristic key points for radiological differentiation have been found. And its definitive diagnosis should be based on the etiological examination.

  9. A national study of individuals who handle migratory birds for evidence of avian and swine-origin influenza virus infections.

    Science.gov (United States)

    Shafir, Shira C; Fuller, Trevon; Smith, Thomas B; Rimoin, Anne W

    2012-08-01

    Persons with occupational or recreational exposure to migratory birds may be at risk for infection with highly pathogenic avian influenza and other avian influenza viruses since wild birds are the natural reservoir of influenza A. Additionally, bird handlers may host avian and swine-origin influenza (pH1N1) virus co-infections, which generate reassortant viruses with high pathogenicity in mammals. We assessed the prevalence of avian and swine influenza viruses in US-based bird handlers and estimated their exposure to different orders of wild birds including waterfowl (Anseriformes), songbirds (Passeriformes), and shorebirds (Charadriiformes). Cross-sectional serologic survey accompanied by a questionnaire to estimate behavioral risk factors. This is first survey of US-based bird handlers who also work at international sites. 401 participants were recruited and tested over the course of 3 years. One participant with occupational exposure to migratory birds had evidence of past infections with a H5N2 virus antigenically related to A/Nopi/MN/07/462960-02, which is the first case of this influenza subtype in a human host associated with exposure to wild rather than domestic birds. We detected no avian and swine-origin influenza virus co-infections. The exposure of bird handlers to songbirds was four times greater than to shorebirds or waterfowl. Though rare, the transmission of avian influenza viruses from migratory birds to US-based bird handlers has potentially significant public health and economic consequences. Copyright © 2012 Elsevier B.V. All rights reserved.

  10. Virus-specific antibodies interfere with avian influenza infection in peripheral blood mononuclear leukocytes from young or aged chickens

    Science.gov (United States)

    Avian influenza virus (AIV) infection was examined in peripheral blood mononuclear leukocyte cultures (PBMC) that were collected from 1-day-old chicks or from 52-week-old chickens. Virus-specific antibodies were incubated with AIV to model maternal antibody interference in vitro. Interferon-alpha (I...

  11. Adjuvant efficacy of mOMV against avian influenza virus infection in mice.

    Science.gov (United States)

    Lee, Byeong-Jae; Lee, Sang-Ho; Song, Min-Suk; Pascua, Philippe Noriel Q; Kwon, Hyeok-il; Park, Su-Jin; Kim, Eun-Ha; Decano, Arun; Kim, Se Mi; Lim, Gyo Jin; Kim, Doo-Jin; Chang, Kyu-Tae; Kim, Sang-Hyun; Choi, Young Ki

    2013-10-01

    Highly pathogenic avian influenza H5N1 viruses are found chiefly in birds and have caused severe disease and death in infected humans. Development of influenza vaccines capable of inducing heterosubtypic immunity against a broad range of influenza viruses is the best option for the preparedness, since vaccination remains the principal method in controlling influenza viral infections. Here, a mOMV-adjuvanted recombinant H5N2 (rH5N2) whole virus antigen vaccine with A/Environment/Korea/W149/06(H5N1)-derived H5 HA and A/Chicken/Korea/ma116/04(H9N2)-derived N2 NA in the backbone of A/Puerto Rico/8/34(H1N1) was prepared and generated by reverse genetics. Groups of mice were vaccinated by a prime-boost regime with the rH5N2 vaccine (1.75 μg of HA with/without 10 μg mOMV or aluminum hydroxide adjuvant for comparison). At two weeks post-immunizations, vaccinated mice were challenged with lethal doses of 10(3.5) EID50/ml of H5N1 or H9N2 avian influenza viruses, and were monitored for 15 days. Both mOMV- and alum-adjuvant vaccine groups had high survival rates after H5N1 infection and low levels of body weight changes compared to control groups. Interestingly, the mOMV-adjuvanted group induced better cross-reactive antibody responses serologically and promoted cross-protectivity against H5N1 and H9N2 virus challenges. Our results suggest that mOMV could be used as a vaccine adjuvant in the development of effective vaccines used to control influenza A virus transmission.

  12. ECOLOGICAL DETERMINANTS OF AVIAN INFLUENZA VIRUS, WEST NILE VIRUS, AND AVIAN PARAMYXOVIRUS INFECTION AND ANTIBODY STATUS IN BLUE-WINGED TEAL (ANAS DISCORS) IN THE CANADIAN PRAIRIES.

    Science.gov (United States)

    Nallar, Rodolfo; Papp, Zsuzsanna; Leighton, Frederick A; Epp, Tasha; Pasick, John; Berhane, Yohannes; Lindsay, Robbin; Soos, Catherine

    2016-01-01

    The Canadian prairies are one of the most important breeding and staging areas for migratory waterfowl in North America. Hundreds of thousands of waterfowl of numerous species from multiple flyways converge in and disperse from this region annually; therefore this region may be a key area for potential intra- and interspecific spread of infectious pathogens among migratory waterfowl in the Americas. Using Blue-winged Teal (Anas discors, BWTE), which have the most extensive migratory range among waterfowl species, we investigated ecologic risk factors for infection and antibody status to avian influenza virus (AIV), West Nile virus (WNV), and avian paramyxovirus-1 (APMV-1) in the three prairie provinces (Alberta, Saskatchewan, and Manitoba) prior to fall migration. We used generalized linear models to examine infection or evidence of exposure in relation to host (age, sex, body condition, exposure to other infections), spatiotemporal (year, province), population-level (local population densities of BWTE, total waterfowl densities), and environmental (local pond densities) factors. The probability of AIV infection in BWTE was associated with host factors (e.g., age and antibody status), population-level factors (e.g., local BWTE population density), and year. An interaction between age and AIV antibody status showed that hatch year birds with antibodies to AIV were more likely to be infected, suggesting an antibody response to an active infection. Infection with AIV was positively associated with local BWTE density, supporting the hypothesis of density-dependent transmission. The presence of antibodies to WNV and APMV-1 was positively associated with age and varied among years. Furthermore, the probability of being WNV antibody positive was positively associated with pond density rather than host population density, likely because ponds provide suitable breeding habitat for mosquitoes, the primary vectors for transmission. Our findings highlight the importance of

  13. PMWS: Experimental model and co-infections

    DEFF Research Database (Denmark)

    Allan, G. M.; McNeilly, F.; Ellis, J

    2004-01-01

    and pneumonia and typical histological lesions include lymphocytic depletion and multinucleated giant cell formation in lymph nodes, degeneration and necrosis of hepatocytes, and multifocal lymphohistocytic interstitial pneumonia. This communication will review the results of experimental infections...

  14. Human and avian extraintestinal pathogenic Escherichia coli: infections, zoonotic risks, and antibiotic resistance trends.

    Science.gov (United States)

    Mellata, Melha

    2013-11-01

    Extraintestinal pathogenic Escherichia coli (ExPEC) constitutes ongoing health concerns for women, newborns, elderly, and immunocompromised individuals due to increased numbers of urinary tract infections (UTIs), newborn meningitis, abdominal sepsis, and septicemia. E. coli remains the leading cause of UTIs, with recent investigations reporting the emergence of E. coli as the predominant cause of nosocomial and neonatal sepsis infections. This shift from the traditional Gram-positive bacterial causes of nosocomial and neonatal sepsis infections could be attributed to the use of intrapartum chemoprophylaxis against Gram-positive bacteria and the appearance of antibiotic (ATB) resistance in E. coli. While ExPEC strains cause significant healthcare concerns, these bacteria also infect chickens and cause the poultry industry economic losses due to costs of containment, mortality, and disposal of carcasses. To circumvent ExPEC-related costs, ATBs are commonly used in the poultry industry to prevent/treat microbial infections and promote growth and performance. In an unfortunate linkage, chicken products are suspected to be a source of foodborne ExPEC infections and ATB resistance in humans. Therefore, the emergence of multidrug resistance (MDR) (resistance to three or more classes of antimicrobial agents) among avian E. coli has created major economic and health concerns, affecting both human healthcare and poultry industries. Increased numbers of immunocompromised individuals, including the elderly, coupled with MDR among ExPEC strains, will continue to challenge the treatment of ExPEC infections and likely lead to increased treatment costs. With ongoing complications due to emerging ATB resistance, novel treatment strategies are necessary to control ExPEC infections. Recognizing and treating the zoonotic risk posed by ExPEC would greatly enhance food safety and positively impact human health.

  15. Comparative haematological changes in experimentally infected ...

    African Journals Online (AJOL)

    A comparative study of haematological changes in Savannah brown goats experimentally infected with Trypanosoma brucei and Trypanosoma vivax was carried out using thirty (30) goats aged between 20 and 48 months and average weight of 13.00 kg. The parameters determined before and after infection included ...

  16. 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, ...

  17. Shedding light on avian influenza H4N6 infection in mallards: modes of transmission and implications for surveillance.

    Directory of Open Access Journals (Sweden)

    Kaci K VanDalen

    Full Text Available BACKGROUND: Wild mallards (Anas platyrhychos are considered one of the primary reservoir species for avian influenza viruses (AIV. Because AIV circulating in wild birds pose an indirect threat to agriculture and human health, understanding the ecology of AIV and developing risk assessments and surveillance systems for prevention of disease is critical. METHODOLOGY/PRINCIPAL FINDINGS: In this study, mallards were experimentally infected with an H4N6 subtype of AIV by oral inoculation or contact with an H4N6 contaminated water source. Cloacal swabs, oropharyngeal swabs, fecal samples, and water samples were collected daily and tested by real-time RT-PCR (RRT-PCR for estimation of viral shedding. Fecal samples had significantly higher virus concentrations than oropharyngeal or cloacal swabs and 6 month old ducks shed significantly more viral RNA than 3 month old ducks regardless of sample type. Use of a water source contaminated by AIV infected mallards, was sufficient to transmit virus to naïve mallards, which shed AIV at higher or similar levels as orally-inoculated ducks. CONCLUSIONS: Bodies of water could serve as a transmission pathway for AIV in waterfowl. For AIV surveillance purposes, water samples and fecal samples appear to be excellent alternatives or additions to cloacal and oropharyngeal swabbing. Furthermore, duck age (even within hatch-year birds may be important when interpreting viral shedding results from experimental infections or surveillance. Differential shedding among hatch-year mallards could affect prevalence estimates, modeling of AIV spread, and subsequent risk assessments.

  18. Avian pox virus infection in a common barn owl (Tyto alba in southern Brazil

    Directory of Open Access Journals (Sweden)

    Gilberto D. Vargas

    2011-07-01

    Full Text Available A young common barn owl (Tyto alba was referred to the Núcleo de Reabilitação da Fauna Silvestre (Nurfs, Federal University of Pelotas (UFPel, after been found in a barn of a brick factory in the urban area of Pelotas, Rio Grande do Sul, Brazil. The bird was apathic, weak and with crusty lesions in the featherless areas (eyes, beak, legs, and died soon after arrival at Nurfs. Necropsy and histopathological examination of the lesions were carried out. The hyperplasia and hypertrophy of the cutaneous lesions, several eosinophilic intracyto-plasmic inclusion bodies in epithelial cells (Bollinger bodies, as well as particles characteristic of poxvirus, observed by electronic microscopy, confirmed the infection by avian poxvirus, what highlights the importance of Tyto alba as carrier of the virus in the wild.

  19. The innate immunity of guinea pigs against highly pathogenic avian influenza virus infection.

    Science.gov (United States)

    Zhang, Kun; Xu, Wei Wei; Zhang, Zhaowei; Liu, Jing; Li, Jing; Sun, Lijuan; Sun, Weiyang; Jiao, Peirong; Sang, Xiaoyu; Ren, Zhiguang; Yu, Zhijun; Li, Yuanguo; Feng, Na; Wang, Tiecheng; Wang, Hualei; Yang, Songtao; Zhao, Yongkun; Zhang, Xuemei; Wilker, Peter R; Liu, WenJun; Liao, Ming; Chen, Hualan; Gao, Yuwei; Xia, Xianzhu

    2017-05-02

    H5N1 avian influenza viruses are a major pandemic concern. In contrast to the highly virulent phenotype of H5N1 in humans and many animal models, guinea pigs do not typically display signs of severe disease in response to H5N1 virus infection. Here, proteomic and transcriptional profiling were applied to identify host factors that account for the observed attenuation of A/Tiger/Harbin/01/2002 (H5N1) virulence in guinea pigs. RIG-I and numerous interferon stimulated genes were among host proteins with altered expression in guinea pig lungs during H5N1 infection. Overexpression of RIG-I or the RIG-I adaptor protein MAVS in guinea pig cell lines inhibited H5N1 replication. Endogenous GBP-1 expression was required for RIG-I mediated inhibition of viral replication upstream of the activity of MAVS. Furthermore, we show that guinea pig complement is involved in viral clearance, the regulation of inflammation, and cellular apoptosis during influenza virus infection of guinea pigs. This work uncovers features of the guinea pig innate immune response to influenza that may render guinea pigs resistant to highly pathogenic influenza viruses.

  20. Identification of Avian Pathogenic Escherichia coli Genes That Are Induced In Vivo during Infection in Chickens

    Science.gov (United States)

    Lebeer, Sarah; Gwakisa, Paul Simon; Goddeeris, Bruno Maria

    2012-01-01

    Avian pathogenic Escherichia coli (APEC) is associated with extraintestinal infections in poultry causing a variety of diseases collectively known as colibacillosis. The host and bacterial factors influencing and/or responsible for carriage and systemic translocation of APEC inside the host are poorly understood. Identification of such factors could help in the understanding of its pathogenesis and in the subsequent development of control strategies. Recombination-based in vivo expression technology (RIVET) was used to identify APEC genes specifically expressed during infection in chickens. A total of 21 clones with in vivo-induced promoters were isolated from chicken livers and spleens, indicative of systemic infection. DNA sequencing of the cloned fragments revealed that 12 of the genes were conserved E. coli genes (metH, lysA, pntA, purL, serS, ybjE, ycdK [rutC], wcaJ, gspL, sdsR, ylbE, and yjiY), 6 of the genes were phage related/associated, and 3 genes were pathogen specific (tkt1, irp2, and eitD). These genes are involved in various cellular functions, such as metabolism, cell envelope and integrity, transport systems, and virulence. Others were phage related or have yet-unknown functions. PMID:22344666

  1. Non-Human Primates Harbor Diverse Mammalian and Avian Astroviruses Including Those Associated with Human Infections.

    Directory of Open Access Journals (Sweden)

    Erik A Karlsson

    Full Text Available Astroviruses (AstVs are positive sense, single-stranded RNA viruses transmitted to a wide range of hosts via the fecal-oral route. The number of AstV-infected animal hosts has rapidly expanded in recent years with many more likely to be discovered because of the advances in viral surveillance and next generation sequencing. Yet no study to date has identified human AstV genotypes in animals, although diverse AstV genotypes similar to animal-origin viruses have been found in children with diarrhea and in one instance of encephalitis. Here we provide important new evidence that non-human primates (NHP can harbor a wide variety of mammalian and avian AstV genotypes, including those only associated with human infection. Serological analyses confirmed that >25% of the NHP tested had antibodies to human AstVs. Further, we identified a recombinant AstV with parental relationships to known human AstVs. Phylogenetic analysis suggests AstVs in NHP are on average evolutionarily much closer to AstVs from other animals than are AstVs from bats, a frequently proposed reservoir. Our studies not only demonstrate that human astroviruses can be detected in NHP but also suggest that NHP are unique in their ability to support diverse AstV genotypes, further challenging the paradigm that astrovirus infection is species-specific.

  2. Avian malaria in Hawaiian forest birds: Infection and population impacts across species and elevations

    Science.gov (United States)

    Samuel, Michael D.; Woodworth, Bethany L.; Atkinson, Carter T.; Hart, P. J.; LaPointe, Dennis

    2015-01-01

    Wildlife diseases can present significant threats to ecological systems and biological diversity, as well as domestic animal and human health. However, determining the dynamics of wildlife diseases and understanding the impact on host populations is a significant challenge. In Hawai‘i, there is ample circumstantial evidence that introduced avian malaria (Plasmodium relictum) has played an important role in the decline and extinction of many native forest birds. However, few studies have attempted to estimate disease transmission and mortality, survival, and individual species impacts in this distinctive ecosystem. We combined multi-state capture-recapture (longitudinal) models with cumulative age-prevalence (cross-sectional) models to evaluate these patterns in Apapane, Hawai‘i Amakihi, and Iiwi in low-, mid-, and high-elevation forests on the island of Hawai‘i based on four longitudinal studies of 3–7 years in length. We found species-specific patterns of malaria prevalence, transmission, and mortality rates that varied among elevations, likely in response to ecological factors that drive mosquito abundance. Malaria infection was highest at low elevations, moderate at mid elevations, and limited in high-elevation forests. Infection rates were highest for Iiwi and Apapane, likely contributing to the absence of these species in low-elevation forests. Adult malaria fatality rates were highest for Iiwi, intermediate for Amakihi at mid and high elevations, and lower for Apapane; low-elevation Amakihi had the lowest malaria fatality, providing strong evidence of malaria tolerance in this low-elevation population. Our study indicates that hatch-year birds may have greater malaria infection and/or fatality rates than adults. Our study also found that mosquitoes prefer feeding on Amakihi rather than Apapane, but Apapane are likely a more important reservoir for malaria transmission to mosquitoes. Our approach, based on host abundance and infection rates, may be an

  3. An experimental Schistosoma mattheei infection in man.

    Science.gov (United States)

    Wolmarans, C T; de Kock, K N; van der Walt, M P

    1990-12-01

    Certain aspects of the immune response of a male experimentally infected with 3-day old cercariae of a pure field strain of Schistosoma matheei were investigated. Among others, aspects such as the reaction of eosinophils, neutrophils and blood platelets after infection, were included in the study. The involvement of IgG and the cross reaction between these antibodies and S. haematobium and S. mansoni were also investigated. The phenomenon that the cercariae were, 3 days after shedding, still capable of penetrating the skin causing an inflammatory response was studied. The results lend some support to the surmise that a pure S. mattheei infection in humans is incapable of any egg production.

  4. Influence of body condition on influenza a virus infection in mallard ducks: Experimental infection data

    Science.gov (United States)

    Arsnoe, D.M.; Ip, Hon S.; Owen, J.C.

    2011-01-01

    Migrating waterfowl are implicated in the global spread of influenza A viruses (IAVs), and mallards (Anas platyrhynchos) are considered a particularly important IAV reservoir. Prevalence of IAV infection in waterfowl peaks during autumn pre-migration staging and then declines as birds reach wintering areas. Migration is energetically costly and birds often experience declines in body condition that may suppress immune function. We assessed how body condition affects susceptibility to infection, viral shedding and antibody production in wild-caught and captive-bred juvenile mallards challenged with low pathogenic avian influenza virus (LPAIV) H5N9. Wild mallards (n = 30) were separated into three experimental groups; each manipulated through food availability to a different condition level (-20%, -10%, and normal ??5% original body condition), and captive-bred mallards (n = 10) were maintained at normal condition. We found that wild mallards in normal condition were more susceptible to LPAIV infection, shed higher peak viral loads and shed viral RNA more frequently compared to birds in poor condition. Antibody production did not differ according to condition. We found that wild mallards did not differ from captive-bred mallards in viral intensity and duration of infection, but they did exhibit lower antibody titers and greater variation in viral load. Our findings suggest that reduced body condition negatively influences waterfowl host competence to LPAIV infection. This observation is contradictory to the recently proposed condition-dependent hypothesis, according to which birds in reduced condition would be more susceptible to IAV infection. The mechanisms responsible for reducing host competency among birds in poor condition remain unknown. Our research indicates body condition may influence the maintenance and spread of LPAIV by migrating waterfowl. ?? 2011 Arsnoe et al.

  5. Selection of reference genes for gene expression analysis by real-time qPCR in avian cells infected with infectious bronchitis virus.

    Science.gov (United States)

    Batra, Ambalika; Maier, Helena J; Fife, Mark S

    2017-04-01

    Infectious bronchitis virus (IBV) causes infectious bronchitis in poultry, a respiratory disease that is a source of major economic loss to the poultry industry. Detection and the study of the molecular pathogenesis of the virus often involve the use of real-time quantitative PCR assays (qPCR). To account for error within the experiments, the levels of target gene transcription are normalized to that of suitable reference genes. Despite publication of the MIQE (Minimum Information for Publication of Quantitative Real-Time PCR Experiments) guidelines in 2009, single un-tested reference genes are often used for normalization of qPCR assays in avian research studies. Here, we use the geNorm algorithm to identify suitable reference genes in different avian cell types during infection with apathogenic and pathogenic strains of IBV. We discuss the importance of selecting an appropriate experimental sample subset for geNorm analysis, and show the effect that this selection can have on resultant reference gene selection. The effects of inappropriate normalization on the transcription pattern of a cellular signalling gene, AKT1, and the interferon-inducible, MX1, were studied. We identify the possibility of the misinterpretation of qPCR data when an inappropriate normalization strategy is employed. This is most notable when measuring the transcription of AKT1, where changes are minimal during infection.

  6. Investigations on the protective role of passively transferred antibodies against avian Metapneumovirus (aMPV) infection in turkeys

    OpenAIRE

    Rubbenstroth, Dennis; Rautenschlein, Silke

    2009-01-01

    Abstract The Avian Metapneumovirus (aMPV) is the causative agent of an acute respiratory disease in turkeys, which causes considerable economic losses to the poultry industry. Currently attenuated live and inactivated vaccines are widely used to control the disease, but vaccine breaks are frequently observed. For improvement of current vaccination strategies it is necessary to gain enhanced knowledge of the immune mechanisms against aMPV infection. Field observations suggest, that ...

  7. Experimental Proteus mirabilis Burn Surface Infection

    Science.gov (United States)

    1982-02-01

    mirabilis Burn Surface Infection Albert T. McManus, PhD; Charles G. McLeod, Jr, DVM; Arthur D. Mason, Jr, MD * We established a human burn Isolate of...William J1. Northam. Peter A. lDorsaneo, and Paulette langlinais MS. model may be useful in evaluation of experimental antibi - prov ided technical support

  8. 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...

  9. Experimental Ascaris suum infection in Yankasa lambs ...

    African Journals Online (AJOL)

    aliyu.jibril

    2017-04-11

    Apr 11, 2017 ... Experimental Ascaris suum infection in Yankasa lambs: Parasitological and pathological observations. I Isah. 1. *, JO Ajanusi. 1. , NP Chiezey. 2. , LB Tekdek. 3. & B Mohammed. 4. 1. Department of Veterinary Parasitology and Entomology, Faculty of Veterinary Medicine,. Ahmadu Bello University, Zaria, ...

  10. Avian research on U.S. Forest Service Experimental Forests and Ranges: Emergent themes, opportunities, and challenges

    Science.gov (United States)

    Stoleson, Scott H.; King, D.I.; Tomosy, M.

    2011-01-01

    Since 1908, U.S. Forest Service Experimental Forests and Ranges have been dedicated to long-term interdisciplinary research on a variety of ecological and management questions. They encompass a wide diversity of life zones and ecoregions, and provide access to research infrastructure, opportunities for controlled manipulations, and integration with other types of long-term data. These features have facilitated important advances in a number of areas of avian research, including furthering our understanding of population dynamics, the effects of forest management on birds, avian responses to disturbances such as fire and hurricanes, and other aspects of avian ecology and conservation. However, despite these contributions, this invaluable resource has been underutilized by ornithologists. Most of the Experimental Forests and Ranges have had no ornithological work done on them. We encourage the ornithological community, especially graduate students and new faculty, to take advantage of this largely untapped potential for long-term work, linkage with long-term data sets, multiple disciplines, and active forest management. ?? 2010 Elsevier B.V.

  11. Effects of Cyclosporin A induced T-lymphocyte depletion on the course of avian Metapneumovirus (aMPV) infection in turkeys

    DEFF Research Database (Denmark)

    Rubbenstroth, Dennis; Dalgaard, Tina S; Kothlow, Sonja

    2010-01-01

    The avian Metapneumovirus (aMPV) causes an economically important acute respiratory disease in turkeys (turkey rhinotracheitis, TRT).While antibodies were shownto be insufficient for protection against a MPV-infection, the role of T-lymphocytes in the control of aMPV-infection is not clear...... to untreated controls (P infection...

  12. Clostridium difficile Infection in Production Animals and Avian Species: A Review.

    Science.gov (United States)

    Moono, Peter; Foster, Niki F; Hampson, David J; Knight, Daniel R; Bloomfield, Lauren E; Riley, Thomas V

    2016-12-01

    Clostridium difficile is the leading cause of antibiotic-associated diarrhea and colitis in hospitalized humans. Recently, C. difficile infection (CDI) has been increasingly recognized as a cause of neonatal enteritis in food animals such as pigs, resulting in stunted growth, delays in weaning, and mortality, as well as colitis in large birds such as ostriches. C. difficile is a strictly anaerobic spore-forming bacterium, which produces two toxins A (TcdA) and B (TcdB) as its main virulence factors. The majority of strains isolated from animals produce an additional binary toxin (C. difficile transferase) that is associated with increased virulence. C. difficile is ubiquitous in the environment and has a wide host range. This review summarizes the epidemiology, clinical presentations, risk factors, and laboratory diagnosis of CDI in animals. Increased awareness by veterinarians and animal owners of the significance of clinical disease caused by C. difficile in livestock and avians is needed. Finally, this review provides an overview on methods for controlling environmental contamination and potential therapeutics available.

  13. Evaluating surveillance strategies for the early detection of low pathogenicity avian influenza infections.

    Directory of Open Access Journals (Sweden)

    Arianna Comin

    Full Text Available In recent years, the early detection of low pathogenicity avian influenza (LPAI viruses in poultry has become increasingly important, given their potential to mutate into highly pathogenic viruses. However, evaluations of LPAI surveillance have mainly focused on prevalence and not on the ability to act as an early warning system. We used a simulation model based on data from Italian LPAI epidemics in turkeys to evaluate different surveillance strategies in terms of their performance as early warning systems. The strategies differed in terms of sample size, sampling frequency, diagnostic tests, and whether or not active surveillance (i.e., routine laboratory testing of farms was performed, and were also tested under different epidemiological scenarios. We compared surveillance strategies by simulating within-farm outbreaks. The output measures were the proportion of infected farms that are detected and the farm reproduction number (R(h. The first one provides an indication of the sensitivity of the surveillance system to detect within-farm infections, whereas R(h reflects the effectiveness of outbreak detection (i.e., if detection occurs soon enough to bring an epidemic under control. Increasing the sampling frequency was the most effective means of improving the timeliness of detection (i.e., it occurs earlier, whereas increasing the sample size increased the likelihood of detection. Surveillance was only effective in preventing an epidemic if actions were taken within two days of sampling. The strategies were not affected by the quality of the diagnostic test, although performing both serological and virological assays increased the sensitivity of active surveillance. Early detection of LPAI outbreaks in turkeys can be achieved by increasing the sampling frequency for active surveillance, though very frequent sampling may not be sustainable in the long term. We suggest that, when no LPAI virus is circulating yet and there is a low risk of virus

  14. Predicting Avian Influenza Co-Infection with H5N1 and H9N2 in Northern Egypt

    Directory of Open Access Journals (Sweden)

    Sean G. Young

    2016-09-01

    Full Text Available Human outbreaks with avian influenza have been, so far, constrained by poor viral adaptation to non-avian hosts. This could be overcome via co-infection, whereby two strains share genetic material, allowing new hybrid strains to emerge. Identifying areas where co-infection is most likely can help target spaces for increased surveillance. Ecological niche modeling using remotely-sensed data can be used for this purpose. H5N1 and H9N2 influenza subtypes are endemic in Egyptian poultry. From 2006 to 2015, over 20,000 poultry and wild birds were tested at farms and live bird markets. Using ecological niche modeling we identified environmental, behavioral, and population characteristics of H5N1 and H9N2 niches within Egypt. Niches differed markedly by subtype. The subtype niches were combined to model co-infection potential with known occurrences used for validation. The distance to live bird markets was a strong predictor of co-infection. Using only single-subtype influenza outbreaks and publicly available ecological data, we identified areas of co-infection potential with high accuracy (area under the receiver operating characteristic (ROC curve (AUC 0.991.

  15. Proteomic analysis of chicken embryonic trachea and kidney tissues after infection in ovo by avian infectious bronchitis coronavirus

    Directory of Open Access Journals (Sweden)

    Kong Xiangang

    2011-03-01

    Full Text Available Abstract Background Avian infectious bronchitis (IB is one of the most serious diseases of economic importance in chickens; it is caused by the avian infectious coronavirus (IBV. Information remains limited about the comparative protein expression profiles of chicken embryonic tissues in response to IBV infection in ovo. In this study, we analyzed the changes of protein expression in trachea and kidney tissues from chicken embryos, following IBV infection in ovo, using two-dimensional gel electrophoresis (2-DE coupled with matrix-assisted laser desorption/ionization time-of-flight tandem mass spectrometry (MALDI-TOF-TOF MS. Results 17 differentially expressed proteins from tracheal tissues and 19 differentially expressed proteins from kidney tissues were identified. These proteins mostly related to the cytoskeleton, binding of calcium ions, the stress response, anti-oxidative, and macromolecular metabolism. Some of these altered proteins were confirmed further at the mRNA level using real-time RT-PCR. Moreover, western blotting analysis further confirmed the changes of annexin A5 and HSPB1 during IBV infection. Conclusions To the best of our knowledge, we have performed the first analysis of the proteomic changes in chicken embryonic trachea and kidney tissues during IBV infection in ovo. The data obtained should facilitate a better understanding of the pathogenesis of IBV infection.

  16. Experimental Campylobacter Jejuni Infection in Humans

    Science.gov (United States)

    1988-03-01

    Blaser MJI Black RE. Duncan DJ, Amer I. Campylobacter Clements ML, Robins-Brone R, Lim Y-L. Duration of jejuni -specific serum antibodies are elevated in...SUBTITLE 5 FUNDING •4UMBERS Experimental Campylobacter jejuni Infection 86PP6826 in Humans 61102A 30161102BS13 AB6. AUTHOR(S)DA328 Robert E. Black...SUPPLEMENTARY NOTES Contract Title: Studies of the Outer Membrane Proteins of Campylobacter Jejuni for Vaccine Development ൔa• DISTRIBUTION

  17. Nonlinear hierarchical modeling of experimental infection data.

    Science.gov (United States)

    Singleton, Michael D; Breheny, Patrick J

    2016-08-01

    In this paper, we propose a nonlinear hierarchical model (NLHM) for analyzing longitudinal experimental infection (EI) data. The NLHM offers several improvements over commonly used alternatives such as repeated measures analysis of variance (RM-ANOVA) and the linear mixed model (LMM). It enables comparison of relevant biological properties of the course of infection including peak intensity, duration and time to peak, rather than simply comparing mean responses at each observation time. We illustrate the practical benefits of this model and the insights it yields using data from experimental infection studies on equine arteritis virus. Finally, we demonstrate via simulation studies that the NLHM substantially reduces bias and improves the power to detect differences in relevant features of the infection response between two populations. For example, to detect a 20% difference in response duration between two groups (n=15) in which the peak time and peak intensity were identical, the RM-ANOVA test had a power of just 11%, and LMM a power of just 12%. By comparison, the nonlinear model we propose had a power of 58% in the same scenario, while controlling the Type I error rate better than the other two methods. Copyright © 2016 Elsevier B.V. All rights reserved.

  18. Avian lipocalin expression in chickens following Escherichia coli infection and inhibition of avian pathogenic Escherichia coli growth by Ex-FABP.

    Science.gov (United States)

    Garénaux, Amélie; Houle, Sébastien; Folch, Benjamin; Dallaire, Geneviève; Truesdell, Mélanie; Lépine, François; Doucet, Nicolas; Dozois, Charles M

    2013-03-15

    Avian pathogenic Escherichia coli (APEC) causes respiratory disease and sepsis in poultry. To persist in its host, E. coli requires essential nutrients including iron. Since iron is limited in extra-intestinal tissues, E. coli produces siderophores, small molecules with high affinity for ferric iron, to sequester this essential nutrient. To counter bacterial siderophore systems, mammalian hosts secrete siderocalin (also called lipocalin 2 or NGAL), which binds ferric-siderophore complexes rendering them unavailable to bacteria. In humans and mice, siderocalin is known to play a role in primary defense against bacterial infections. In poultry, 4 proteins display homology to the human NGAL (CALβ, CALγ, Ggal-C8GC and Ex-FABP). The function and expression of the genes coding for these 4 proteins during infection by APEC is still unknown. Expression levels of these genes were determined by quantitative RT-PCR using RNA extracted from lungs, livers and spleens of healthy 3-week-old chickens and chickens infected with APEC. The gene coding for Ex-FABP was overexpressed in all organs tested. It was significantly more overexpressed in the lungs and liver than in the spleen (37.3 and 27.3 times versus 11.5 times, respectively). The genes coding for Calβ and Calγ were also found significantly overexpressed in the liver (27 and 8.2 times, respectively). To confirm the function of Ex-FABP as a siderocalin, the gene coding for this protein was cloned in an expression vector and the protein was purified. In vitro growth inhibition of E. coli strains by Ex-FABP was assayed in parallel with growth inhibition caused by human siderocalin. Purified Ex-FABP inhibited growth of E. coli K-12, which only produces the siderophore enterobactin. However, E. coli strains producing pathogen-associated siderophores including salmochelins (glucosylated enterobactin), aerobactin and yersiniabactin grew normally in the presence of Ex-FABP. These results indicate that Ex-FABP is an avian

  19. Strategies for differentiating infection in vaccinated animals (DIVA) for foot-and-mouth disease, classical swine fever and avian influenza

    DEFF Research Database (Denmark)

    Uttenthal, Åse; Parida, Satya; Rasmussen, Thomas Bruun

    2010-01-01

    The prophylactic use of vaccines against exotic viral infections in production animals is undertaken exclusively in regions where the disease concerned is endemic. In such areas, the infection pressure is very high and so, to assure optimal protection, the most efficient vaccines are used. However......, in areas considered to be free from these diseases and in which there is the possibility of only limited outbreaks, the use of Differentiation of Infected from Vaccinated Animals (DIVA) or marker vaccines allows for vaccination while still retaining the possibility of serological surveillance...... for the presence of infection. This literature review describes the current knowledge on the use of DIVA diagnostic strategies for three important transboundary animal diseases: foot-and-mouth disease in cloven-hoofed animals, classical swine fever in pigs and avian influenza in poultry....

  20. Seroevidence for a High Prevalence of Subclinical Infection With Avian Influenza A(H5N1) Virus Among Workers in a Live-Poultry Market in Indonesia.

    Science.gov (United States)

    Shimizu, Kazufumi; Wulandari, Laksmi; Poetranto, Emmanuel D; Setyoningrum, Retno A; Yudhawati, Resti; Sholikhah, Amelia; Nastri, Aldise M; Poetranto, Anna L; Candra, Adithya Y R; Puruhito, Edith F; Takahara, Yusuke; Yamagishi, Yoshiaki; Yamaoka, Masaoki; Hotta, Hak; Ustumi, Takako; Lusida, Maria I; Soetjipto; Shimizu, Yohko K; Soegiarto, Gatot; Mori, Yasuko

    2016-12-15

     In Indonesia, highly pathogenic avian influenza A(H5N1) virus has become endemic in poultry and has caused sporadic deadly infections in human. Since 2012, we have conducted fixed-point surveillance of avian influenza viruses at a live-poultry market in East Java, Indonesia. In this study, we examined the seroprevalence of avian influenza A(H5N1) virus infection among market workers.  Sera were collected from 101 workers in early 2014 and examined for antibody activity against avian A(H5N1) Eurasian lineage virus by a hemagglutination-inhibition (HI) assay.  By the HI assay, 84% of the sera tested positive for antibody activity against the avian virus. Further analysis revealed that the average HI titer in 2014 was 2.9-fold higher than in 2012 and that seroconversion occurred in 44% of paired sera (11 of 25) between 2012 and 2014. A medical history survey was performed in 2016; responses to questionnaires indicated that none of workers had had severe acute respiratory illness during 2013.  This study provides evidence of a high prevalence of avian A(H5N1) virus infection in 2013 among workers at a live-poultry market. However, because no instances of hospitalizations were reported, we can conclude the virus did not manifest any clinical symptoms in workers. © The Author 2016. Published by Oxford University Press for the Infectious Diseases Society of America.

  1. Impact of highly pathogenic avian influenza virus strain on generation and transmission of bioaerosols during simulated slaughter of infected chickens and ducks

    Science.gov (United States)

    Human infections with H5N1 highly pathogenic avian influenza (HPAI) virus occur following exposure to H5N1 virus-infected poultry, often during home slaughter or live-poultry market slaughter processes. Using bioaerosol samplers, we demonstrated that infectious H5N1 airborne particles were produced ...

  2. Synthetic virus-like particles prepared via protein corona formation enable effective vaccination in an avian model of coronavirus infection.

    Science.gov (United States)

    Chen, Hui-Wen; Huang, Chen-Yu; Lin, Shu-Yi; Fang, Zih-Syun; Hsu, Chen-Hsuan; Lin, Jung-Chen; Chen, Yuan-I; Yao, Bing-Yu; Hu, Che-Ming J

    2016-11-01

    The ongoing battle against current and rising viral infectious threats has prompted increasing effort in the development of vaccine technology. A major thrust in vaccine research focuses on developing formulations with virus-like features towards enhancing antigen presentation and immune processing. Herein, a facile approach to formulate synthetic virus-like particles (sVLPs) is demonstrated by exploiting the phenomenon of protein corona formation induced by the high-energy surfaces of synthetic nanoparticles. Using an avian coronavirus spike protein as a model antigen, sVLPs were prepared by incubating 100 nm gold nanoparticles in a solution containing an optimized concentration of viral proteins. Following removal of free proteins, antigen-laden particles were recovered and showed morphological semblance to natural viral particles under nanoparticle tracking analysis and transmission electron microscopy. As compared to inoculation with free proteins, vaccination with the sVLPs showed enhanced lymphatic antigen delivery, stronger antibody titers, increased splenic T-cell response, and reduced infection-associated symptoms in an avian model of coronavirus infection. Comparison to a commercial whole inactivated virus vaccine also showed evidence of superior antiviral protection by the sVLPs. The study demonstrates a simple yet robust method in bridging viral antigens with synthetic nanoparticles for improved vaccine application; it has practical implications in the management of human viral infections as well as in animal agriculture. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. CD36 deficiency attenuates experimental mycobacterial infection

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    Min-Oo Gundula

    2010-10-01

    Full Text Available Abstract Background Members of the CD36 scavenger receptor family have been implicated as sensors of microbial products that mediate phagocytosis and inflammation in response to a broad range of pathogens. We investigated the role of CD36 in host response to mycobacterial infection. Methods Experimental Mycobacterium bovis Bacillus Calmette-Guérin (BCG infection in Cd36+/+ and Cd36-/- mice, and in vitro co-cultivation of M. tuberculosis, BCG and M. marinum with Cd36+/+ and Cd36-/-murine macrophages. Results Using an in vivo model of BCG infection in Cd36+/+ and Cd36-/- mice, we found that mycobacterial burden in liver and spleen is reduced (83% lower peak splenic colony forming units, p Cd36-/- animals. Intracellular growth of all three mycobacterial species was reduced in Cd36-/- relative to wild type Cd36+/+ macrophages in vitro. This difference was not attributable to alterations in mycobacterial uptake, macrophage viability, rate of macrophage apoptosis, production of reactive oxygen and/or nitrogen species, TNF or interleukin-10. Using an in vitro model designed to recapitulate cellular events implicated in mycobacterial infection and dissemination in vivo (i.e., phagocytosis of apoptotic macrophages containing mycobacteria, we demonstrated reduced recovery of viable mycobacteria within Cd36-/- macrophages. Conclusions Together, these data indicate that CD36 deficiency confers resistance to mycobacterial infection. This observation is best explained by reduced intracellular survival of mycobacteria in the Cd36-/- macrophage and a role for CD36 in the cellular events involved in granuloma formation that promote early bacterial expansion and dissemination.

  4. Rhinovirus genome evolution during experimental human infection.

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    Samuel Cordey

    Full Text Available Human rhinoviruses (HRVs evolve rapidly due in part to their error-prone RNA polymerase. Knowledge of the diversity of HRV populations emerging during the course of a natural infection is essential and represents a basis for the design of future potential vaccines and antiviral drugs. To evaluate HRV evolution in humans, nasal wash samples were collected daily for five days from 15 immunocompetent volunteers experimentally infected with a reference stock of HRV-39. In parallel, HeLa-OH cells were inoculated to compare HRV evolution in vitro. Nasal wash in vivo assessed by real-time PCR showed a viral load that peaked at 48-72 h. Ultra-deep sequencing was used to compare the low-frequency mutation populations present in the HRV-39 inoculum in two human subjects and one HeLa-OH supernatant collected 5 days post-infection. The analysis revealed hypervariable mutation locations in VP2, VP3, VP1, 2C and 3C genes and conserved regions in VP4, 2A, 2B, 3A, 3B and 3D genes. These results were confirmed by classical sequencing of additional samples, both from inoculated volunteers and independent cell infections, and suggest that HRV inter-host transmission is not associated with a strong bottleneck effect. A specific analysis of the VP1 capsid gene of 15 human cases confirmed the high mutation incidence in this capsid region, but not in the antiviral drug-binding pocket. We could also estimate a mutation frequency in vivo of 3.4x10(-4 mutations/nucleotides and 3.1x10(-4 over the entire ORF and VP1 gene, respectively. In vivo, HRV generate new variants rapidly during the course of an acute infection due to mutations that accumulate in hot spot regions located at the capsid level, as well as in 2C and 3C genes.

  5. Experimental vaccines against potentially pandemic and highly pathogenic avian influenza viruses

    OpenAIRE

    Mooney, Alaina J; Tompkins, S Mark

    2013-01-01

    Influenza A viruses continue to emerge and re-emerge, causing outbreaks, epidemics and occasionally pandemics. While the influenza vaccines licensed for public use are generally effective against seasonal influenza, issues arise with production, immunogenicity, and efficacy in the case of vaccines against pandemic and emerging influenza viruses, and highly pathogenic avian influenza virus in particular. Thus, there is need of improved influenza vaccines and vaccination strategies. This review...

  6. Detection of infectious laryngotracheitis virus by real-time PCR in naturally and experimentally infected chickens.

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    Yan Zhao

    Full Text Available Infectious laryngotracheitis (ILT is an acute, highly contagious upper-respiratory infectious disease of chickens. In this study, a real-time PCR method was developed for fast and accurate detection and quantitation of ILTV DNA of chickens experimentally infected with ILTV strain LJS09 and naturally infected chickens. The detection lower limit of the assay was 10 copies of DNA. There were no cross reactions with the DNA and RNA of infectious bursal disease virus, chicken anemia virus, reticuloendotheliosis virus, avian reovirus, Newcastle disease virus, and Marek's disease virus. The real-time PCR was reproducible as the coefficients of variation of reproducibility of the intra-assay and the inter-assay were less than 2%. The real-time PCR was used to detect the levels of the ILTV DNA in the tissues of specific pathogen free (SPF chickens infected with ILTV at different times post infection. ILTV DNA was detected by real-time PCR in the heart, liver, spleen, lung, kidney, larynx, tongue, thymus, glandular stomach, duodenum, pancreatic gland, small intestine, large intestine, cecum, cecal tonsil, bursa of Fabricius, and brain of chickens in the infection group and the contact-exposure group. The sensitivity, specificity, and reproducibility of the ILTV real-time PCR assay revealed its suitability for detection and quantitation of ILTV in the samples from clinically and experimentally ILTV infected chickens.

  7. Avian influenza.

    Science.gov (United States)

    Zeitlin, Gary A; Maslow, Melanie J

    2006-03-01

    The current epidemic of H5N1 highly pathogenic avian influenza in Southeast Asia raises serious concerns that genetic reassortment will result in the next influenza pandemic. There have been 164 confirmed cases of human infection with avian influenza since 1996. In 2004 alone, there were 45 cases of human H5N1 in Vietnam and Thailand, with a mortality rate over 70%. In addition to the potential public health hazard, the current zoonotic epidemic has caused severe economic losses. Efforts must be concentrated on early detection of bird outbreaks with aggressive culling, quarantines, and disinfection. To prepare for and prevent increased human cases, it is essential to improve detection methods and stockpile effective antivirals. Novel therapeutic modalities, including short, interfering RNAs and new vaccine strategies that use plasmid-based genetic systems offer promise, should a pandemic occur.

  8. The Induction of Protective Immunity against Experimental Eimeria tenella Infection using Serum Exosomes

    Science.gov (United States)

    Avian coccidiosis is caused by Eimeria, a unicellular, apicomplexan protist which primarily infects intestinal epithelia resulting in nutrition malabsorption and reduced growth of commercial poultry. Vaccination of chickens with exosomes isolated from antigen presenting cells and containing parasit...

  9. Antibody and inflammatory responses in laying hens with experimental primary infections of Ascaridia galli.

    Science.gov (United States)

    Marcos-Atxutegi, C; Gandolfi, B; Arangüena, T; Sepúlveda, R; Arévalo, M; Simón, F

    2009-04-06

    Ascaridia galli, an intestinal nematode that affects hens and other domestic and wild birds, causes economic losses in avian exploitations. The present work shows that A. galli stimulates a strong antibody response as well as an intense inflammatory reaction, in the intestinal mucous of experimentally infected Lohmann Brown laying hens. IgG antibodies against soluble extracts of A. galli embrionated eggs and adult worms, were detected in both blood and yolks eggs from infected hens during a period of 105 days after the infection. This indicates that hens transfer to their offspring a part of the IgG antibodies produced when they become infected. The antigens responsible for the stimulation of specific IgG were molecules of 30-34, 44-54 and 58-90 kDa, while in the yolk eggs of infected hens a reactivity directed against antigens of molecular weight (M(w)) lower than 50 kDa was detected. Histology revealed traumatic lesions with leukocyte infiltration, and inflammation of the intestinal wall of the infected hens after 105 days of initial infection. The possible influence of the immune and inflammatory response on the population dynamics of the parasite is discussed.

  10. A cross-sectional serological survey of the Dutch commercial poultry population for the presence of Low Pathogenic Avian Influenza virus infection

    NARCIS (Netherlands)

    Wit, de J.J.; Koch, G.; Fabri, T.H.F.; Elbers, A.R.W.

    2004-01-01

    After the discovery of poultry infected with highly pathogenic avian influenza (HPAI) virus of subtype H7N7 in the central area of the Netherlands on 28 February 2003, the hypothesis was put forward that an outbreak of the low pathogenic (LP) variant of H7N7 had preceded, unnoticed, the occurrence

  11. First natural infection by Ascocotyle (Phagicola longa Ransom (Digenea, Heterophyidae in an avian host, Ardea cocoi Linnaeus (Aves, Ciconiiformes, Ardeidae in Brazil

    Directory of Open Access Journals (Sweden)

    Luciano Antunes Barros

    2002-03-01

    Full Text Available The first case of a natural avian infection caused by the digenetic trematode Ascocotyle (Phagicola longa Ransom, 1920 in Brazil, is reported from the ardeid bird Ardea cocoi Linnaeus, 1766. This represents a new host record and data on clinical and pathological findings are also reported.

  12. Highly pathogenic avian influenza virus H5N1 infection in a long-distance migrant shorebird under migratory and non-migratory states

    NARCIS (Netherlands)

    Reperant, Leslie A.; Bildt, Marco W.G. van de; Amerongen, Geert van; Buehler, Deborah; Osterhaus, Albert D.M.E.; Jenni-Eiermann, Susi; Piersma, Theunis; Kuiken, Thijs

    2011-01-01

    Corticosterone regulates physiological changes preparing wild birds for migration. It also modulates the immune system and may lead to increased susceptibility to infection, with implications for the spread of pathogens, including highly pathogenic avian influenza virus (HPAIV) H5N1. The red knot

  13. Highly pathogenic avian influenza virus H5N1 infection in a long-distance migrant shorebird under migratory and non-migratory states

    NARCIS (Netherlands)

    L.A. Reperant (Leslie); M.W.G. van de Bildt (Marco); G. van Amerongen (Geert); D.M. Buehler (Debbie); A.D.M.E. Osterhaus (Albert); S. Jenni-Eiermann (Susi); T. Piersma (Theunis); T. Kuiken (Thijs)

    2011-01-01

    textabstractCorticosterone regulates physiological changes preparing wild birds for migration. It also modulates the immune system and may lead to increased susceptibility to infection, with implications for the spread of pathogens, including highly pathogenic avian influenza virus (HPAIV) H5N1. The

  14. Avian response to timber harvesting applied experimentally to manage Cerulean Warbler breeding populations

    Science.gov (United States)

    Sheehan, James; Wood, Petra Bohall; Buehler, David A.; Keyser, Patrick D.; Larkin, Jeffrey L.; Rodewald, Amanda D.; Wigley, T. Bently; Boves, Than J.; George, Gregory A.; Bakermans, Marja H.; Beachy, Tiffany A.; Evans, Andrea; McDermott, Molly E.; Newell, Felicity L.; Perkins, Kelly A.; White, Matthew

    2014-01-01

    Timber harvesting has been proposed as a management tool to enhance breeding habitat for the Cerulean Warbler (Setophaga cerulea), a declining Neotropical–Nearctic migratory songbird that nests in the canopy of mature eastern deciduous forests. To evaluate how this single-species management focus might fit within an ecologically based management approach for multiple forest birds, we performed a manipulative experiment using four treatments (three intensities of timber harvests and an unharvested control) at each of seven study areas within the core Cerulean Warbler breeding range. We collected pre-harvest (one year) and post-harvest (four years) data on the territory density of Cerulean Warblers and six additional focal species, avian community relative abundance, and several key habitat variables. We evaluated the avian and habitat responses across the 3–32 m2 ha−1 residual basal area (RBA) range of the treatments. Cerulean Warbler territory density peaked with medium RBA (∼16 m2 ha−1). In contrast, territory densities of the other focal species were negatively related to RBA (e.g., Hooded Warbler [Setophaga citrina]), were positively related to RBA (e.g., Ovenbird [Seiurus aurocapilla]), or were not sensitive to this measure (Scarlet Tanager [Piranga olivacea]). Some species (e.g., Hooded Warbler) increased with time post-treatment and were likely tied to a developing understory, whereas declines (e.g., Ovenbird) were immediate. Relative abundance responses of additional species were consistent with the territory density responses of the focal species. Across the RBA gradient, greatest separation in the avian community was between early successional forest species (e.g., Yellow-breasted Chat [Icteria virens]) and closed-canopy mature forest species (e.g., Ovenbird), with the Cerulean Warbler and other species located intermediate to these two extremes. Overall, our results suggest that harvests within 10–20 m2 ha−1 RBA yield the largest

  15. Infectious bronchitis corona virus establishes productive infection in avian macrophages interfering with selected antimicrobial functions.

    Science.gov (United States)

    Amarasinghe, Aruna; Abdul-Cader, Mohamed Sarjoon; Nazir, Sadiya; De Silva Senapathi, Upasama; van der Meer, Frank; Cork, Susan Catherine; Gomis, Susantha; Abdul-Careem, Mohamed Faizal

    2017-01-01

    Infectious bronchitis virus (IBV) causes respiratory disease leading to loss of egg and meat production in chickens. Although it is known that macrophage numbers are elevated in the respiratory tract of IBV infected chickens, the role played by macrophages in IBV infection, particularly as a target cell for viral replication, is unknown. In this study, first, we investigated the ability of IBV to establish productive replication in macrophages in lungs and trachea in vivo and in macrophage cell cultures in vitro using two pathogenic IBV strains. Using a double immunofluorescent technique, we observed that both IBV Massachusetts-type 41 (M41) and Connecticut A5968 (Conn A5968) strains replicate in avian macrophages at a low level in vivo. This in vivo observation was substantiated by demonstrating IBV antigens in macrophages following in vitro IBV infection. Further, IBV productive infection in macrophages was confirmed by demonstrating corona viral particles in macrophages and IBV ribonucleic acid (RNA) in culture supernatants. Evaluation of the functions of macrophages following infection of macrophages with IBV M41 and Conn A5968 strains revealed that the production of antimicrobial molecule, nitric oxide (NO) is inhibited. It was also noted that replication of IBV M41 and Conn A5968 strains in macrophages does not interfere with the induction of type 1 IFN activity by macrophages. In conclusion, both M41 and Con A5968 IBV strains infect macrophages in vivo and in vitro resulting productive replications. During the replication of IBV in macrophages, their ability to produce NO can be affected without affecting the ability to induce type 1 IFN activity. Further studies are warranted to uncover the significance of macrophage infection of IBV in the pathogenesis of IBV infection in chickens.

  16. Infectious bronchitis corona virus establishes productive infection in avian macrophages interfering with selected antimicrobial functions.

    Directory of Open Access Journals (Sweden)

    Aruna Amarasinghe

    Full Text Available Infectious bronchitis virus (IBV causes respiratory disease leading to loss of egg and meat production in chickens. Although it is known that macrophage numbers are elevated in the respiratory tract of IBV infected chickens, the role played by macrophages in IBV infection, particularly as a target cell for viral replication, is unknown. In this study, first, we investigated the ability of IBV to establish productive replication in macrophages in lungs and trachea in vivo and in macrophage cell cultures in vitro using two pathogenic IBV strains. Using a double immunofluorescent technique, we observed that both IBV Massachusetts-type 41 (M41 and Connecticut A5968 (Conn A5968 strains replicate in avian macrophages at a low level in vivo. This in vivo observation was substantiated by demonstrating IBV antigens in macrophages following in vitro IBV infection. Further, IBV productive infection in macrophages was confirmed by demonstrating corona viral particles in macrophages and IBV ribonucleic acid (RNA in culture supernatants. Evaluation of the functions of macrophages following infection of macrophages with IBV M41 and Conn A5968 strains revealed that the production of antimicrobial molecule, nitric oxide (NO is inhibited. It was also noted that replication of IBV M41 and Conn A5968 strains in macrophages does not interfere with the induction of type 1 IFN activity by macrophages. In conclusion, both M41 and Con A5968 IBV strains infect macrophages in vivo and in vitro resulting productive replications. During the replication of IBV in macrophages, their ability to produce NO can be affected without affecting the ability to induce type 1 IFN activity. Further studies are warranted to uncover the significance of macrophage infection of IBV in the pathogenesis of IBV infection in chickens.

  17. Experimental analysis of the auditory detection process on avian point counts

    Science.gov (United States)

    Simons, T.R.; Alldredge, M.W.; Pollock, K.H.; Wettroth, J.M.

    2007-01-01

    We have developed a system for simulating the conditions of avian surveys in which birds are identified by sound. The system uses a laptop computer to control a set of amplified MP3 players placed at known locations around a survey point. The system can realistically simulate a known population of songbirds under a range of factors that affect detection probabilities. The goals of our research are to describe the sources and range of variability affecting point-count estimates and to find applications of sampling theory and methodologies that produce practical improvements in the quality of bird-census data. Initial experiments in an open field showed that, on average, observers tend to undercount birds on unlimited-radius counts, though the proportion of birds counted by individual observers ranged from 81% to 132% of the actual total. In contrast to the unlimited-radius counts, when data were truncated at a 50-m radius around the point, observers overestimated the total population by 17% to 122%. Results also illustrate how detection distances decline and identification errors increase with increasing levels of ambient noise. Overall, the proportion of birds heard by observers decreased by 28 ± 4.7% under breezy conditions, 41 ± 5.2% with the presence of additional background birds, and 42 ± 3.4% with the addition of 10 dB of white noise. These findings illustrate some of the inherent difficulties in interpreting avian abundance estimates based on auditory detections, and why estimates that do not account for variations in detection probability will not withstand critical scrutiny.

  18. The first case of H5N1 avian influenza infection in a human with complications of adult respiratory distress syndrome and Reye's syndrome.

    Science.gov (United States)

    Ku, A S; Chan, L T

    1999-04-01

    Avian influenza virus was not known to cause systemic infection in humans before. We report a 3-year-old boy with good past health who developed pneumonia caused by H5N1 avian influenza A virus (A/Hong Kong/156/97). The virus was isolated from a tracheal aspirate. There were complications of Reye's syndrome, adult respiratory distress syndrome, and multiple organ system failure. He had a history of receiving aspirin. His adult respiratory distress syndrome did not respond to endotracheal surfactant replacement therapy. He died 6 days after admission. Clinicians should be alert to the importance of a new human influenza strain.

  19. Comparison of argentinean saint louis encephalitis virus non-epidemic and epidemic strain infections in an avian model.

    Directory of Open Access Journals (Sweden)

    Luis Adrián Diaz

    2011-05-01

    Full Text Available St. Louis encephalitis virus (SLEV, Flavivirus, Flaviviridae is an emerging mosquito-borne pathogen in South America, with human SLEV encephalitis cases reported in Argentina and Brazil. Genotype III strains of SLEV were isolated from Culex quinquefasciatus mosquitoes in Cordoba, Argentina in 2005, during the largest SLEV outbreak ever reported in South America. The present study tested the hypothesis that the recent, epidemic SLEV strain exhibits greater virulence in birds as compared with a non-epidemic genotype III strain isolated from mosquitoes in Santa Fe Province 27 years earlier. The observed differences in infection parameters between adult House sparrows (Passer domesticus that were needle-inoculated with either the epidemic or historic SLEV strain were not statistically significant. However, only the House sparrows that were infected with the epidemic strain achieved infectious-level viremia titers sufficient to infect Cx. spp. mosquitoes vectors. Furthermore, the vertebrate reservoir competence index values indicated an approximately 3-fold increase in amplification potential of House sparrows infected with the epidemic strain when pre-existing flavivirus-reactive antibodies were present, suggesting the possibility that antibody-dependent enhancement may increase the risk of avian-amplified transmission of SLEV in South America.

  20. Avian influenza

    Directory of Open Access Journals (Sweden)

    Tjandra Y. Aditama

    2006-06-01

    Full Text Available Avian influenza, or “bird flu”, is a contagious disease of animals which crossed the species barrier to infect humans and gave a quite impact on public health in the world since 2004, especially due to the threat of pandemic situation. Until 1st March 2006, laboratory-confirmed human cases have been reported in seven countries: Cambodia, Indonesia, Thailand, Viet Nam, China, Iraq and Turkey with a total of 174 cases and 94 dead (54.02%. Indonesia has 27 cases, 20 were dead (74.07%. AI cases in Indonesia are more in male (62.5% and all have a symptom of fever. An influenza pandemic is a rare but recurrent event. An influenza pandemic happens when a new subtype emerges that has not previously circulated in humans. For this reason, avian H5N1 is a strain with pandemic potential, since it might ultimately adapt into a strain that is contagious among humans. Impact of the pandemic could include high rates of illness and worker absenteeism are expected, and these will contribute to social and economic disruption. Historically, the number of deaths during a pandemic has varied greatly. Death rates are largely determined by four factors: the number of people who become infected, the virulence of the virus, the underlying characteristics and vulnerability of affected populations, and the effectiveness of preventive measures. Accurate predictions of mortality cannot be made before the pandemic virus emerges and begins to spread. (Med J Indones 2006; 15:125-8Keywords: Avian Influenza, Pandemic

  1. Epidemiology of Salmonella typhimurium O:4-12 infection in Norway: evidence of transmission from an avian wildlife reservoir.

    Science.gov (United States)

    Kapperud, G; Stenwig, H; Lassen, J

    1998-04-15

    In 1987, a nationwide outbreak of Salmonella typhimurium O:4-12 infection traced to contaminated chocolate bars occurred in Norway. In the 5 years after the outbreak, elevated numbers of sporadic cases caused by the epidemic strain of Salmonella were detected, followed by a decline in subsequent years. To characterize the epidemiology of this infection, the authors analyzed information concerning all sporadic cases reported in Norway from 1966 to 1996. Of the 153 patients infected by the outbreak strain, 43% were less than 5 years of age, and only three persons had acquired the infection abroad. In contrast, 46% of the cases attributable to other S. typhimurium O:4-12 variants and 90% of the total number of Salmonella infections were related to foreign travel. A distinct seasonality was observed: 76% of the cases appeared between January and April. At the same time of year, the epidemic strain was regularly encountered as the etiologic agent of fatal salmonellosis among wild passerine birds, suggesting an epidemiologic link between the avian and human cases. The strain was rarely isolated from other sources. From 1990 to 1992, the authors conducted a prospective case-control study of sporadic indigenous infections to identify risk factors and obtain guidance for preventive efforts. Forty-one case-patients, each matched by age, sex, and geographic area with two population controls, were enrolled. In conditional logistic regression analysis, the following environmental factors were independently related to an increased risk of infection: drinking untreated water, having direct contact with wild birds or their droppings, and eating snow, sand, or soil. Cases were also more likely than controls to report having antecedent or concurrent medical disorders. Forty-six percent of the study patients were hospitalized for their salmonellosis.

  2. Serological evidence of avian encephalomyelitis virus and Pasteurella multocida infections in free-range indigenous chickens in Southern Mozambique.

    Science.gov (United States)

    Taunde, Paula; Timbe, Palmira; Lucas, Ana Felicidade; Tchamo, Cesaltina; Chilundo, Abel; Dos Anjos, Filomena; Costa, Rosa; Bila, Custodio Gabriel

    2017-06-01

    A total of 398 serum samples from free-range indigenous chickens originating from four villages in Southern Mozambique were tested for the presence of avian encephalomyelitis virus (AEV) and Pasteurella multocida (PM) antibodies through commercial enzyme-linked immunosorbent assay (ELISA) kits. AEV and PM antibodies were detected in all villages surveyed. The proportion of positive samples was very high: 59.5% (95% confidence interval (CI) 51.7-67.7%) for AEV and 71.5% (95% CI 67.7-77.3%) for PM. Our findings revealed that these pathogens are widespread among free-range indigenous chickens in the studied villages and may represent a threat in the transmission of AEV and PM to wild, broiler or layer chickens in the region. Further research is warranted on epidemiology of circulating strains and impact of infection on the poultry industry.

  3. A Case Report of Avian Polyomavirus Infection in a Blue Fronted Parrot (Amazona aestiva Associated with Anemia

    Directory of Open Access Journals (Sweden)

    Natalia Azevedo Philadelpho

    2015-01-01

    Full Text Available An adult Blue Fronted Amazon parrot (A. aestiva presenting with emesis, apathy, undigested seed in feces, and severe anemia was treated for approximately 2 months. Upon radiographic examination, an enlarged kidney was the only alteration. PCR for avian Bornavirus, Circovirus, and Polyomavirus was performed for the feces and blood. The results were positive for APV in both samples and negative for the other viruses. After 6 months, the feces from the same animal were negative for APV. Because the animal was positive for APV in both the feces and the blood, it is likely that these clinical symptoms were due to Polyomavirus infection. Severe anemia is an unusual clinical sign of Polyomavirus, and this study aims to identify novel differential diagnostic criteria for the disease.

  4. Protection from avian influenza H5N1 virus infection with antibody-impregnated filters

    Directory of Open Access Journals (Sweden)

    Tsukamoto Masaya

    2011-02-01

    Full Text Available Abstract There is worldwide concern over the possibility of a new influenza pandemic originating from the highly pathogenic avian H5N1 influenza viruses. We herein demonstrate that functional air filters impregnated with ostrich antibodies against the hemagglutinin of the H5N1 virus protect chickens from death by H5N1 transmission. These results suggest that the use of ostrich antibody-impregnated filters might be a powerful way to prevent the transmission of H5N1.

  5. Differentially expressed genes in a flock of Chinese local-breed chickens infected with a subgroup J avian leukosis virus using suppression subtractive hybridization

    OpenAIRE

    Guiping Zhao; Maiqing Zheng; Jilan Chen; Jie Wen; Chunmei Wu; Wenjuan Li; Libo Liu; Yuan Zhang

    2010-01-01

    Avian leukosis virus subgroup J (ALV-J) is a new type of virus that mainly induces myeloid leukosis (ML) in chickens. To further elucidate the pathogenesis of ALV-J infection and tumor development, expression profiles from the bone marrow tissue of 15 infected and 18 non-infected birds from a local-breed poultry-farm under naturally infected conditions, were analyzed by suppression-subtractive hybridization. The birds were diagnosed as ML+ (or ML-) by specific ALV-J detection methods, involvi...

  6. The pathology observed in experimental Fasciola gigantica infected ...

    African Journals Online (AJOL)

    Pathological lesions were observed in four Fasciola gigantica infected Yankasa sheep that died at the 10th, 11th and 12th week post-infection in an experimental infection at the Reproduction unit of the National Animal production Research institute, Shika-Zaria, Nigeria. The experiment involved twelve Yankasa sheep that ...

  7. PLASMODIUM BERGHEI: CYCLICAL TRANSMISSIONS BY EXPERIMENTALLY INFECTED ANOPHELES QUADRIMACULATUS.

    Science.gov (United States)

    YOELI, M; MOST, H; BONE, G

    1964-06-26

    A number of strains of Plasmodium berghei were isolated from sporozoites of Anopheles dureni. Laboratory-bred Anopheles quadrimaculatus fed on carriers of the newly isolated strains showed overwhelming midgut infections and moderate or mild salivary gland infections. Successive cyclic transmissions by the bite of experimentally infected A. quadrimaculatus in laboratorybred tree rats (Thamnomys surdaster) were carried out.

  8. Temporal changes in the expression of avian β-defensins in the chicken vagina during sexual maturation and Salmonella infection.

    Science.gov (United States)

    Anastasiadou, Maria; Avdi, Melpomeni; Theodoridis, Alexandros; Michailidis, Georgios

    2013-06-01

    Avian β-defensins (AvβDs) constitute a family of antimicrobial peptides that are critical to innate immunity in chickens, providing protection against microbial pathogens including Salmonella Enteritidis (SE). As apart from the digestive tract another main route of SE colonization in birds is via infection of the oviduct and specifically of the vagina, the aim of this study was to investigate the expression of the complete family of AvβDs, in the chicken vagina in vivo, to determine whether sexual maturation affects their mRNA abundance and to investigate whether SE infection alters the vaginal AvβDs expression. Expression analysis revealed that 11 members of the AvβD family were expressed in the chicken vagina. Quantitative real-time PCR analysis revealed that the mRNA abundance of five AvβDs was up regulated and of one AvβD was down regulated with respect to sexual maturation. In addition SE infection resulted in a significant induction of AvβD5, 7, 10, 11, 12 and 14 in the vagina of sexually mature birds, and in a significant induction of AvβD5 and 11 in the vagina of aged birds. These findings provide strong evidence to suggest that an AvβD-mediated immune response mechanism exists in the chicken vagina providing protection against bacterial pathogens including Salmonella species.

  9. Global and Quantitative Proteomic Analysis of Dogs Infected by Avian-like H3N2 Canine Influenza Virus

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    Shuo eSu

    2015-04-01

    Full Text Available Canine influenza virus A (H3N2 is a newly emerged etiological agent for respiratory infections in dogs. The mechanism of interspecies transmission from avian to canine species and the development of diseases in this new host remain to be explored. To investigate this, we conducted a differential proteomics study in two-month old beagles inoculated intranasally with 106 TCID50 of A/canine/Guangdong/01/2006 (H3N2 virus. Lung sections excised at 12 hours post-inoculation (hpi, 4 days, and 7 days post-inoculation (dpi were processed for global and quantitative analysis of differentially expressed proteins. A total of 17,796 proteins were identified at different time points. About 1.6% was differentially expressed between normal and infected samples. Of these, 23, 27 and 136 polypeptides were up-regulated, and 14, 18 and 123 polypeptides were down-regulated, at 12 hpi, 4 dpi, and 7 dpi, respectively. Vann diagram analysis indicated that 17 proteins were up-regulated and one was down-regulated at all three time points. Selected proteins were validated by real-time PCR and by Western blot. Our results show that apoptosis and cytoskeleton-associated proteins expression was suppressed, whereas interferon-induced proteins plus other innate immunity proteins were induced after the infection. Understanding of the interactions between virus and the host will provide insights into the basis of interspecies transmission, adaptation, and virus pathogenicity.

  10. Microwave or autoclave treatments destroy the infectivity of infectious bronchitis virus and avian pneumovirus but allow detection by reverse transcriptase-polymerase chain reaction.

    Science.gov (United States)

    Elhafi, G; Naylor, C J; Savage, C E; Jones, R C

    2004-06-01

    A method is described for enabling safe transit of denatured virus samples for polymerase chain reaction (PCR) identification without the risk of unwanted viable viruses. Cotton swabs dipped in avian infectious bronchitis virus (IBV) or avian pneumovirus (APV) were allowed to dry. Newcastle disease virus and avian influenza viruses were used as controls. Autoclaving and microwave treatment for as little as 20 sec destroyed the infectivity of all four viruses. However, both IBV and APV could be detected by reverse transcriptase (RT)-PCR after autoclaving and as long as 5 min microwave treatment (Newcastle disease virus and avian influenza viruses were not tested). Double microwave treatment of IBV and APV with an interval of 2 to 7 days between was tested. After the second treatment, RT-PCR products were readily detected in all samples. Swabs from the tracheas and cloacas of chicks infected with IBV shown to contain infectious virus were microwaved. Swabs from both sources were positive by RT-PCR. Microwave treatment appears to be a satisfactory method of inactivating virus while preserving nucleic acid for PCR identification.

  11. Experimental pandemic (H1N1) 2009 virus infection of cats

    NARCIS (Netherlands)

    J.M.A. van den Brand (Judith); K.J. Stittelaar (Koert); G. van Amerongen (Geert); M.W.G. van de Bildt (Marco); L.M.E. Leijten (Lonneke); T. Kuiken (Thijs); A.D.M.E. Osterhaus (Albert)

    2010-01-01

    textabstractTo demonstrate that pandemic (H1N1) 2009 virus may cause respiratory disease in cats, we intratracheally infected cats. Diffuse alveolar damage developed. Seroconversion of sentinel cats indicated cat-to-cat virus transmission. Unlike in cats infected with highly pathogenic avian

  12. Complete Genomic and Lysis-Cassette Characterization of the Novel Phage, KBNP1315, which Infects Avian Pathogenic Escherichia coli (APEC).

    Science.gov (United States)

    Lee, Jung Seok; Jang, Ho Bin; Kim, Ki Sei; Kim, Tae Hwan; Im, Se Pyeong; Kim, Si Won; Lazarte, Jassy Mary S; Kim, Jae Sung; Jung, Tae Sung

    2015-01-01

    Avian pathogenic Escherichia coli (APEC) is a major pathogen that causes avian colibacillosis and is associated with severe economic losses in the chicken-farming industry. Here, bacteriophage KBNP1315, infecting APEC strain KBP1315, was genomically and functionally characterized. The evolutionary relationships of KBNP1315 were analyzed at the genomic level using gene (protein)-sharing networks, the Markov clustering (MCL) algorithm, and comparative genomics. Our network analysis showed that KBNP1315 was connected to 30 members of the Autographivirinae subfamily, which comprises the SP6-, T7-, P60-, phiKMV-, GAP227- and KP34-related groups. Network decomposition suggested that KBNP1315 belongs to the SP6-like phages, but our comparison of putative encoded proteins revealed that key proteins of KBNP1315, including the tail spike protein and endolysin, had relative low levels of amino acid sequence similarity with other members of the SP6-like phages. Thus KBNP1315 may only be distantly related to the SP6-like phages, and (based on the difference in endolysin) its lysis mechanism may differ from theirs. To characterize the lytic functions of the holin and endolysin proteins from KBNP1315, we expressed these proteins individually or simultaneously in E. coli BL21 (DE3) competent cell. Interestingly, the expressed endolysin was secreted into the periplasm and caused a high degree of host cell lysis that was dose-dependently delayed/blocked by NaN3-mediated inhibition of the SecA pathway. The expressed holin triggered only a moderate inhibition of cell growth, whereas coexpression of holin and endolysin enhanced the lytic effect of endolysin. Together, these results revealed that KBNP1315 appears to use a pin-holin/signal-arrest-release (SAR) endolysin pathway to trigger host cell lysis.

  13. Complete Genomic and Lysis-Cassette Characterization of the Novel Phage, KBNP1315, which Infects Avian Pathogenic Escherichia coli (APEC.

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    Jung Seok Lee

    Full Text Available Avian pathogenic Escherichia coli (APEC is a major pathogen that causes avian colibacillosis and is associated with severe economic losses in the chicken-farming industry. Here, bacteriophage KBNP1315, infecting APEC strain KBP1315, was genomically and functionally characterized. The evolutionary relationships of KBNP1315 were analyzed at the genomic level using gene (protein-sharing networks, the Markov clustering (MCL algorithm, and comparative genomics. Our network analysis showed that KBNP1315 was connected to 30 members of the Autographivirinae subfamily, which comprises the SP6-, T7-, P60-, phiKMV-, GAP227- and KP34-related groups. Network decomposition suggested that KBNP1315 belongs to the SP6-like phages, but our comparison of putative encoded proteins revealed that key proteins of KBNP1315, including the tail spike protein and endolysin, had relative low levels of amino acid sequence similarity with other members of the SP6-like phages. Thus KBNP1315 may only be distantly related to the SP6-like phages, and (based on the difference in endolysin its lysis mechanism may differ from theirs. To characterize the lytic functions of the holin and endolysin proteins from KBNP1315, we expressed these proteins individually or simultaneously in E. coli BL21 (DE3 competent cell. Interestingly, the expressed endolysin was secreted into the periplasm and caused a high degree of host cell lysis that was dose-dependently delayed/blocked by NaN3-mediated inhibition of the SecA pathway. The expressed holin triggered only a moderate inhibition of cell growth, whereas coexpression of holin and endolysin enhanced the lytic effect of endolysin. Together, these results revealed that KBNP1315 appears to use a pin-holin/signal-arrest-release (SAR endolysin pathway to trigger host cell lysis.

  14. Increased avian diversity is associated with lower incidence of human West Nile infection: observation of the dilution effect.

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    John P Swaddle

    Full Text Available Recent infectious disease models illustrate a suite of mechanisms that can result in lower incidence of disease in areas of higher disease host diversity--the 'dilution effect'. These models are particularly applicable to human zoonoses, which are infectious diseases of wildlife that spill over into human populations. As many recent emerging infectious diseases are zoonoses, the mechanisms that underlie the 'dilution effect' are potentially widely applicable and could contribute greatly to our understanding of a suite of diseases. The dilution effect has largely been observed in the context of Lyme disease and the predictions of the underlying models have rarely been examined for other infectious diseases on a broad geographic scale. Here, we explored whether the dilution effect can be observed in the relationship between the incidence of human West Nile virus (WNV infection and bird (host diversity in the eastern US. We constructed a novel geospatial contrasts analysis that compares the small differences in avian diversity of neighboring US counties (where one county reported human cases of WNV and the other reported no cases with associated between-county differences in human disease. We also controlled for confounding factors of climate, regional variation in mosquito vector type, urbanization, and human socioeconomic factors that are all likely to affect human disease incidence. We found there is lower incidence of human WNV in eastern US counties that have greater avian (viral host diversity. This pattern exists when examining diversity-disease relationships both before WNV reached the US (in 1998 and once the epidemic was underway (in 2002. The robust disease-diversity relationships confirm that the dilution effect can be observed in another emerging infectious disease and illustrate an important ecosystem service provided by biodiversity, further supporting the growing view that protecting biodiversity should be considered in public

  15. Host behaviour and physiology underpin individual variation in avian influenza virus infection in migratory Bewick's swans

    NARCIS (Netherlands)

    Hoye, B.J.; Fouchier, R.A.M; Klaassen, M.R.J.

    2012-01-01

    Individual variation in infection modulates both the dynamics of pathogens and their impact on host populations. It is therefore crucial to identify differential patterns of infection and understand the mechanisms responsible. Yet our understanding of infection heterogeneity in wildlife is limited,

  16. Field Investigation on the Prevalence of Avian Influenza Virus Infection in Some Localities in Saudi Arabia

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    Abdullah N. Alkhalaf

    2010-07-01

    Full Text Available The objective of this study was to find out prevalence and types of avian influenza virus (AIV among broilers, native chickens, ducks and pigeons in Saudi Arabia. Field investigation was carried out in four localities including Al-Qassim, Hail, Al-Jouf and Northern Border regions. Serum sample, tracheal and cloacal swabs were collected from broilers (n=1561, layers (n=988, ducks (n=329 and pigeons (n=450 from these localities and tested for three different avian influenza viruses (H9, H5 and H3 using Enzyme linked immunosorbent (ELISA test, hamagglutination inhibition (HI test and polymerase chain reaction (PCR. All tested samples were negative for H5 and H3 viruses. In contrast, all positive results were found to be for H9 AI virus using PCR, ELISA and HI test. Chicken sera tested by ELISA for AIV revealed the highest positive samples in Northern Border regions (45.71%, followed by Al-Jouf (29.65%, Al-Qassim (23.98% and Hial (20.94% with non-significant difference (χ2=5.983; P=0.112. HI test carried out on duck sera revealed 35.90% prevalence of antibodies against AIV. PCR amplification resulted in 34.28 and 21.36% positive samples in ducks and chickens, respectively. The highest (45.71% PCR positive chicken samples were from Northern Border regions, followed by Al-Jouf (24.13%, Al-Qassim (19.30% and Hail (16.69% with significant difference (χ2=7.620; P=0.055. All tested pigeons samples were negative for the three virus serotypes included in the study.

  17. A cross-sectional serological survey of the Dutch commercial poultry population for the presence of low pathogenic avian influenza virus infections.

    Science.gov (United States)

    de Wit, J J; Koch, G; Fabri, T H F; Elbers, A R W

    2004-12-01

    After the discovery of poultry infected with highly pathogenic avian influenza (HPAI) virus of subtype H7N7 in the central area of The Netherlands on 28 February 2003, the hypothesis was put forward that an outbreak of the low pathogenic (LP) variant of H7N7 had preceded, unnoticed, the occurrence of the HPAI virus. Consequently, a cross-sectional serological survey of the Dutch poultry population was executed in the second week of March 2003. The basic requirements set were detection of a 5% prevalence of flocks exposed to LPAI virus with 95% confidence within the production type stratification level within each province in The Netherlands. Because of supposed higher risk of avian influenza infections in ducks, turkeys and free-range poultry, all the commercial flocks of these production types present in The Netherlands were sampled. The serological screening of 28018 sera from 1193 randomly selected poultry farms, located outside surveillance zones showed that LPAI H7 virus infections had occurred on three neighbouring farms all located in the southwest of The Netherlands. No antibodies against the neuraminidase N7 subtype were detected in the sera of these farms, indicating that the subtype was different from the HPAI H7N7 subtype that caused the avian influenza epidemic in 2003. In addition, evidence of infections with non-H5 or non-H7 subtypes of influenza A virus were obtained in two other farms located in the northeast and the southeast of The Netherlands. It was concluded that the HPAI subtype H7N7 outbreak was most likely not preceded by a significant circulation of a LPAI subtype H7N7 virus. Based on the Dutch experience, recommendations are made to detect avian influenza infections faster in the future.

  18. Little evidence of avian or equine influenza virus infection among a cohort of Mongolian adults with animal exposures, 2010-2011.

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    Nyamdavaa Khurelbaatar

    Full Text Available Avian (AIV and equine influenza virus (EIV have been repeatedly shown to circulate among Mongolia's migrating birds or domestic horses. In 2009, 439 Mongolian adults, many with occupational exposure to animals, were enrolled in a prospective cohort study of zoonotic influenza transmission. Sera were drawn upon enrollment and again at 12 and 24 months. Participants were contacted monthly for 24 months and queried regarding episodes of acute influenza-like illnesses (ILI. Cohort members confirmed to have acute influenza A infections, permitted respiratory swab collections which were studied with rRT-PCR for influenza A. Serologic assays were performed against equine, avian, and human influenza viruses. Over the 2 yrs of follow-up, 100 ILI investigations in the cohort were conducted. Thirty-six ILI cases (36% were identified as influenza A infections by rRT-PCR; none yielded evidence for AIV or EIV. Serological examination of 12 mo and 24 mo annual sera revealed 37 participants had detectable antibody titers (≥1∶10 against studied viruses during the course of study follow-up: 21 against A/Equine/Mongolia/01/2008(H3N8; 4 against an avian A/Teal/Hong Kong/w3129(H6N1, 11 against an avian-like A/Hong Kong/1073/1999(H9N2, and 1 against an avian A/Migrating duck/Hong Kong/MPD268/2007(H10N4 virus. However, all such titers were <1∶80 and none were statistically associated with avian or horse exposures. A number of subjects had evidence of seroconversion to zoonotic viruses, but the 4-fold titer changes were again not associated with avian or horse exposures. As elevated antibodies against seasonal influenza viruses were high during the study period, it seems likely that cross-reacting antibodies against seasonal human influenza viruses were a cause of the low-level seroreactivity against AIV or EIV. Despite the presence of AIV and EIV circulating among wild birds and horses in Mongolia, there was little evidence of AIV or EIV infection in this

  19. Evaluation of an experimental irradiated oocyst vaccine to protect broiler chicks against avian coccidiosis.

    Science.gov (United States)

    Fetterer, Raymond H; Jenkins, Mark C; Miska, Katarzyna B; Barfield, Ruth C

    2014-09-01

    The current study investigates the use of irradiated oocysts to protect broiler chicks, raised on litter, from infection with multiple species of Eimeria. In order to determine the optimum radiation dose for each Eimeria species, 1-day-old chicks were immunized with oocysts of Eimeria maxima, Eimeria acervulina, or Eimeria tenella exposed to gamma radiation ranging from 0-500 Gy. The litter oocyst counts at 7 days postimmunization, and the effect on weight gain following a challenge infection, decreased with an optimum dose between 150-200 Gy. Based on this finding, broiler chicks were immunized with a mixture of E. maxima, E. acervulina, and E tenella that had been exposed to 150 or 200 Gy. This resulted in more than a 100-fold reduction in litter oocyst counts and significant protection from a challenge infection, as measured by improved weight gain and feed conversion ratio (FCR). Immunization of birds with oocysts receiving 200 Gy was less effective in providing protection from a challenge infection. An additional formulation of vaccines containing two different oocyst doses of the three species that had been irradiated with 150 Gy were evaluated in their ability to attenuate oocyst output and convey protection to challenge. Results were similar with both high and low numbers of irradiated oocysts. Immunized chicks shed less oocysts at 7 days postimmunization and were protected from negative effects of challenge infection as measured by FCR, changes in weight gain, lesion scores, and measurement of body composition. However, the level of protection was somewhat less than that achieved by immunization with nonirradiated oocysts. The overall conclusion is that an irradiated oocyst vaccine developed in this study can effectively protect chicks that are raised on litter from challenge infection with multiple species of Eimeria, comparable to vaccines with virulent or precocious strains.

  20. Deep sequencing-based transcriptome analysis of chicken spleen in response to avian pathogenic Escherichia coli (APEC) infection.

    Science.gov (United States)

    Nie, Qinghua; Sandford, Erin E; Zhang, Xiquan; Nolan, Lisa K; Lamont, Susan J

    2012-01-01

    Avian pathogenic Escherichia coli (APEC) leads to economic losses in poultry production and is also a threat to human health. The goal of this study was to characterize the chicken spleen transcriptome and to identify candidate genes for response and resistance to APEC infection using Solexa sequencing. We obtained 14422935, 14104324, and 14954692 Solexa read pairs for non-challenged (NC), challenged-mild pathology (MD), and challenged-severe pathology (SV), respectively. A total of 148197 contigs and 98461 unigenes were assembled, of which 134949 contigs and 91890 unigenes match the chicken genome. In total, 12272 annotated unigenes take part in biological processes (11664), cellular components (11927), and molecular functions (11963). Summing three specific contrasts, 13650 significantly differentially expressed unigenes were found in NC Vs. MD (6844), NC Vs. SV (7764), and MD Vs. SV (2320). Some unigenes (e.g. CD148, CD45 and LCK) were involved in crucial pathways, such as the T cell receptor (TCR) signaling pathway and microbial metabolism in diverse environments. This study facilitates understanding of the genetic architecture of the chicken spleen transcriptome, and has identified candidate genes for host response to APEC infection.

  1. Deep sequencing-based transcriptome analysis of chicken spleen in response to avian pathogenic Escherichia coli (APEC infection.

    Directory of Open Access Journals (Sweden)

    Qinghua Nie

    Full Text Available Avian pathogenic Escherichia coli (APEC leads to economic losses in poultry production and is also a threat to human health. The goal of this study was to characterize the chicken spleen transcriptome and to identify candidate genes for response and resistance to APEC infection using Solexa sequencing. We obtained 14422935, 14104324, and 14954692 Solexa read pairs for non-challenged (NC, challenged-mild pathology (MD, and challenged-severe pathology (SV, respectively. A total of 148197 contigs and 98461 unigenes were assembled, of which 134949 contigs and 91890 unigenes match the chicken genome. In total, 12272 annotated unigenes take part in biological processes (11664, cellular components (11927, and molecular functions (11963. Summing three specific contrasts, 13650 significantly differentially expressed unigenes were found in NC Vs. MD (6844, NC Vs. SV (7764, and MD Vs. SV (2320. Some unigenes (e.g. CD148, CD45 and LCK were involved in crucial pathways, such as the T cell receptor (TCR signaling pathway and microbial metabolism in diverse environments. This study facilitates understanding of the genetic architecture of the chicken spleen transcriptome, and has identified candidate genes for host response to APEC infection.

  2. The dynamics of avian influenza in western Arctic snow geese: implications for annual and migratory infection patterns

    Science.gov (United States)

    Samuel, Michael D.; Hall, Jeffrey S.; Brown, Justin D.; Goldberg, Diana R.; Ip, Hon S.; Baranyuk, Vasily V.

    2015-01-01

    Wild water birds are the natural reservoir for low-pathogenic avian influenza viruses (AIV). However, our ability to investigate the epizootiology of AIV in these migratory populations is challenging, and despite intensive worldwide surveillance, remains poorly understood. We conducted a cross-sectional, retrospective analysis in Pacific Flyway lesser snow geese Chen caerulescens to investigate AIV serology and infection patterns. We collected nearly 3,000 sera samples from snow geese at 2 breeding colonies in Russia and Canada during 1993-1996 and swab samples from > 4,000 birds at wintering and migration areas in the United States during 2006-2011. We found seroprevalence and annual seroconversion varied considerably among years. Seroconversion and infection rates also differed between snow goose breeding colonies and wintering areas, suggesting that AIV exposure in this gregarious waterfowl species is likely occurring during several phases (migration, wintering and potentially breeding areas) of the annual cycle. We estimated AIV antibody persistence was longer (14 months) in female geese compared to males (6 months). This relatively long period of AIV antibody persistence suggests that subtype-specific serology may be an effective tool for detection of exposure to subtypes associated with highly-pathogenic AIV. Our study provides further evidence of high seroprevalence in Arctic goose populations, and estimates of annual AIV seroconversion and antibody persistence for North American waterfowl. We suggest future AIV studies include serology to help elucidate the epizootiological dynamics of AIV in wild bird populations.

  3. Understanding the ecological drivers of avian influenza virus infection in wildfowl: a continental-scale study across Africa

    Science.gov (United States)

    Gaidet, N.; Caron, A.; Cappelle, J.; Cumming, G. S.; Balança, G.; Hammoumi, S.; Cattoli, G.; Abolnik, C.; Servan de Almeida, R.; Gil, P.; Fereidouni, S. R.; Grosbois, V.; Tran, A.; Mundava, J.; Fofana, B.; Ould El Mamy, A. B.; Ndlovu, M.; Mondain-Monval, J. Y.; Triplet, P.; Hagemeijer, W.; Karesh, W. B.; Newman, S. H.; Dodman, T.

    2012-01-01

    Despite considerable effort for surveillance of wild birds for avian influenza viruses (AIVs), empirical investigations of ecological drivers of AIV prevalence in wild birds are still scarce. Here we used a continental-scale dataset, collected in tropical wetlands of 15 African countries, to test the relative roles of a range of ecological factors on patterns of AIV prevalence in wildfowl. Seasonal and geographical variations in prevalence were positively related to the local density of the wildfowl community and to the wintering period of Eurasian migratory birds in Africa. The predominant influence of wildfowl density with no influence of climatic conditions suggests, in contrast to temperate regions, a predominant role for inter-individual transmission rather than transmission via long-lived virus persisting in the environment. Higher prevalences were found in Anas species than in non-Anas species even when we account for differences in their foraging behaviour (primarily dabbling or not) or their geographical origin (Eurasian or Afro-tropical), suggesting the existence of intrinsic differences between wildfowl taxonomic groups in receptivity to infection. Birds were found infected as often in oropharyngeal as in cloacal samples, but rarely for both types of sample concurrently, indicating that both respiratory and digestive tracts may be important for AIV replication. PMID:21920984

  4. Lethal infection by a novel reassortant H5N1 avian influenza A virus in a zoo-housed tiger.

    Science.gov (United States)

    He, Shang; Shi, Jianzhong; Qi, Xian; Huang, Guoqing; Chen, Hualan; Lu, Chengping

    2015-01-01

    In early 2013, a Bengal tiger (Panthera tigris) in a zoo died of respiratory distress. All specimens from the tiger were positive for HPAI H5N1, which were detected by real-time PCR, including nose swab, throat swab, tracheal swab, heart, liver, spleen, lung, kidney, aquae pericardii and cerebrospinal fluid. One stain of virus, A/Tiger/JS/1/2013, was isolated from the lung sample. Pathogenicity experiments showed that the isolate was able to replicate and cause death in mice. Phylogenetic analysis indicated that HA and NA of A/Tiger/JS/1/2013 clustered with A/duck/Vietnam/OIE-2202/2012 (H5N1), which belongs to clade 2.3.2.1. Interestingly, the gene segment PB2 shared 98% homology with A/wild duck/Korea/CSM-28/20/2010 (H4N6), which suggested that A/Tiger/JS/1/2013 is a novel reassortant H5N1 subtype virus. Immunohistochemical analysis also confirmed that the tiger was infected by this new reassortant HPAI H5N1 virus. Overall, our results showed that this Bengal tiger was infected by a novel reassortant H5N1, suggesting that the H5N1 virus can successfully cross species barriers from avian to mammal through reassortment. Copyright © 2014 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

  5. Avian anemia's

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    Raukar Jelena

    2005-01-01

    Full Text Available This paper deals with avian anemia's classified by MCHC/MCV and with types of anemia's. Father hematological and immunological research is needed to secure information on hematological parameters in different avian species at their earliest age. Anemia is a common clinical finding in birds because the avian erythrocyte half - life is much shorter than the mammalian. Therefore anemia should be determined as soon as possible. Researchers should standardize hematological parameters for every single avian species.

  6. Vertical transmission of avian leukosis virus subgroup J (ALV-J) from hens infected through artificial insemination with ALV-J infected semen.

    Science.gov (United States)

    Li, Yang; Cui, Shuai; Li, Weihua; Wang, Yixin; Cui, Zhizhong; Zhao, Peng; Chang, Shuang

    2017-06-29

    Avian leukosis virus (ALV) is one of the main causes of tumour development within the poultry industry in China. The subgroup J avian leukosis viruses (ALV-J), which induce erythroblastosis and myelocytomatosis, have the greatest pathogenicity and transmission ability within this class of viruses. ALV can be transmitted both horizontally and vertically; however, the effects of ALV infection in chickens-especially roosters-during the propagation, on future generations is not clear. Knowing the role of the cock in the transmission of ALV from generation to generation might contribute to the eradication programs for ALV. The results showed that two hens inseminated with ALV-J-positive semen developed temporary antibody responses to ALV-J at 4-5 weeks post insemination. The p27 antigen was detected in cloacal swabs of six hens, and in 3 of 26 egg albumens at 1-6 weeks after insemination. Moreover, no viremia was detected at 6 weeks after insemination even when virus isolation had been conducted six times at weekly intervals for each of the 12 females. However, ALV-J was isolated from 1 of their 34 progeny chicks at 1 week of age, and its gp85 had 98.4%-99.2% sequence identity with the gp85 of ALV-J isolated from semen samples of the six cocks. Our findings indicated that females that were late horizontally infected with ALV-J by artificial insemination might transmit the virus to progeny through eggs, which amounts to vertical transmission.

  7. Analysis of the crow lung transcriptome in response to infection with highly pathogenic H5N1 avian influenza virus.

    Science.gov (United States)

    Vijayakumar, Periyasamy; Mishra, Anamika; Ranaware, Pradip B; Kolte, Atul P; Kulkarni, Diwakar D; Burt, David W; Raut, Ashwin Ashok

    2015-03-15

    The highly pathogenic avian influenza (HPAI) H5N1 virus, currently circulating in Asia, causes severe disease in domestic poultry as well as wild birds like crow. However, the molecular pathogenesis of HPAIV infection in crows and other wild birds is not well known. Thus, as a step to explore it, a comprehensive global gene expression analysis was performed on crow lungs, infected with HPAI H5N1 crow isolate (A/Crow/India/11TI11/2011) using high throughput next generation sequencing (NGS) (GS FLX Titanium XLR70). The reference genome of crow is not available, so RNA seq analysis was performed on the basis of a de novo assembled transcriptome. The RNA seq result shows, 4052 genes were expressed uniquely in noninfected, 6277 genes were expressed uniquely in HPAIV infected sample and of the 6814 genes expressed in both samples, 2279 genes were significantly differentially expressed. Our transcriptome profile data allows for the ability to understand the molecular mechanism behind the recent lethal HPAIV outbreak in crows which was, until recently, thought to cause lethal infections only in gallinaceous birds such as chickens, but not in wild birds. The pattern of differentially expressed genes suggest that this isolate of H5N1 virus evades the host innate immune response by attenuating interferon (IFN)-inducible signalling possibly by down regulating the signalling from type I IFN (IFNAR1 and IFNAR2) and type II IFN receptors, upregulation of the signalling inhibitors suppressor of cytokine signalling 1 (SOCS1) and SOCS3 and altering the expression of toll-like receptors (TLRs). This may be the reason for disease and mortality in crows. Copyright © 2015. Published by Elsevier B.V.

  8. Avian influenza

    Science.gov (United States)

    Bird flu; H5N1; H5N2; H5N8; H7N9; Avian influenza A (HPAI) H5 ... The first avian influenza in humans was reported in Hong Kong in 1997. It was called avian influenza (H5N1). The outbreak was linked ...

  9. Experimental Infections Of Domestic Rabbits ( Oryctolagus cuniculus ...

    African Journals Online (AJOL)

    Nigerian Journal of Animal Production ... Comparative study of single infections of domestic rabbits (Oryctolagus cuniculus) with Nigerian isolates of Trypanosoma brucei (Gboko strain), and Trypanosoma congolense (Binchi ... Eighteen rabbits of 10-14 weeks old weighing between 600-1200 grams were used for the study.

  10. Experimental Infection of Sheep using Infective Lar- vae (L3 ...

    African Journals Online (AJOL)

    Vet. J., 2014, 18 (2), 71-81 ther research is recommended to determine the impact of multiple-species habitat ... to be reservoir hosts of helminth infections than wild species (Cook et al., 1979;. Richardson and Demarias .... coincidentally there was also a positive relationship, Regression statistics. (R²=0.6696) between total ...

  11. Avian influenza surveillance and diagnosis

    Science.gov (United States)

    Rapid detection and accurate identification of low (LPAI) and high pathogenicity avian influenza (HPAI) is critical to controlling infections and disease in poultry. Test selection and algorithms for the detection and diagnosis of avian influenza virus (AIV) in poultry may vary somewhat among differ...

  12. Parasitological and molecular diagnosis in experimental Strongyloides venezuelensis infection.

    Science.gov (United States)

    Paula, Fabiana Martins; Sitta, Renata Barnabé; Malta, Fernanda Mello; Gottardi, Maiara; Corral, Marcelo Andreetta; Gryschek, Ronaldo César Borges; Chieffi, Pedro Paulo

    2013-01-01

    Strongyloides venezuelensis is a parasitic nematode of rats which is frequently used as a model to study human and animal strongyloidiasis. The aim of this study was to evaluate the correlation between parasitological and molecular diagnosis in Strongyloides venezuelensis infection. PCR assays were used to detect S. venezuelensis DNA in fecal samples obtained from experimentally infected Rattus norvegicus. The results showed a higher sensitivity of the PCR assay in detecting the infection compared to parasitological methods.

  13. 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

  14. Changes in microbiota during experimental human Rhinovirus infection

    NARCIS (Netherlands)

    Hofstra, J. J.; Matamoros, S.; van de Pol, M. A.; de Wever, B.; Tanck, M. W.; Wendt-Knol, H.; Deijs, M.; van der Hoek, L.; Wolthers, K. C.; Molenkamp, R.; Visser, C. E.; Sterk, P. J.; Lutter, R.; de Jong, M. D.

    2015-01-01

    Human Rhinovirus (HRV) is responsible for the majority of common colds and is frequently accompanied by secondary bacterial infections through poorly understood mechanisms. We investigated the effects of experimental human HRV serotype 16 infection on the upper respiratory tract microbiota. Six

  15. Experimental manipulation of avian social structure reveals segregation is carried over across contexts.

    Science.gov (United States)

    Firth, Josh A; Sheldon, Ben C

    2015-03-07

    Our current understanding of animal social networks is largely based on observations or experiments that do not directly manipulate associations between individuals. Consequently, evidence relating to the causal processes underlying such networks is limited. By imposing specified rules controlling individual access to feeding stations, we directly manipulated the foraging social network of a wild bird community, thus demonstrating how external factors can shape social structure. We show that experimentally imposed constraints were carried over into patterns of association at unrestricted, ephemeral food patches, as well as at nesting sites during breeding territory prospecting. Hence, different social contexts can be causally linked, and constraints at one level may have consequences that extend into other aspects of sociality. Finally, the imposed assortment was lost following the cessation of the experimental manipulation, indicating the potential for previously perturbed social networks of wild animals to recover from segregation driven by external constraints.

  16. Detection of reticuloendotheliosis virus by immunohistochemistry and in situ hybridization in experimentally infected Japanese quail embryos and archived formalin-fixed and paraffin-embedded tumours

    National Research Council Canada - National Science Library

    Santos, Vitor L. S. L; Williams, Susan M; Zavala, Guillermo; Barbosa, Taylor; Zhang, Jian; Cheng, Sunny; Shivaprasad, H. L; Hafner, Scott; Fadly, Aly; Santos, Renato L; Brown, Corrie C

    2008-01-01

    .... Histopathological changes in REV infection are not sufficient to differentiate it from avian lymphoid leukosis and Marek's disease, and currently there are no available in situ diagnostic methods...

  17. Low viral doses are sufficient to infect cottontail rabbits with avian influenza A virus.

    Science.gov (United States)

    Root, J Jeffrey; Shriner, Susan A; Ellis, Jeremy W; VanDalen, Kaci K; Sullivan, Heather J

    2017-11-01

    Influenza A viruses (IAVs) have been reported in wild lagomorphs in environments where they share resources with waterfowl. Recent studies have conclusively shown that a North American lagomorph, cottontail rabbits (Sylvilagus sp.), become infected following exposure to IAVs and can shed significant quantities of virus. However, the minimum infectious dose and the efficiency of various routes of infection have not been evaluated. Thirty-six cottontail rabbits were used in a dose response study assessing both the oral and nasal routes of infection. The nasal route of infection proved to be the most efficient, as all cottontail rabbits shed viral RNA following inoculation with doses as low as 102 EID50. The oral route of infection was less efficient, but still produced infection rates of ≥ 50% at relatively low doses (i.e., 103 and 104 EID50). These results suggest that cottontail rabbits are highly susceptible to IAVs at low exposure doses that have been routinely observed in environments contaminated by waterfowl. Furthermore, this study supports earlier observations that cottontail rabbits may pose a biosecurity risk to poultry operations, as a virus-contaminated water source or contaminated environment, even at low viral titers, could be sufficient to initiate viral replication in cottontail rabbits.

  18. Tropism and Infectivity of Influenza Virus, Including Highly Pathogenic Avian H5N1 Virus, in Ferret Tracheal Differentiated Primary Epithelial Cell Cultures

    Science.gov (United States)

    Zeng, Hui; Goldsmith, Cynthia S.; Maines, Taronna R.; Belser, Jessica A.; Gustin, Kortney M.; Pekosz, Andrew; Zaki, Sherif R.; Katz, Jacqueline M.

    2013-01-01

    Tropism and adaptation of influenza viruses to new hosts is partly dependent on the distribution of the sialic acid (SA) receptors to which the viral hemagglutinin (HA) binds. Ferrets have been established as a valuable in vivo model of influenza virus pathogenesis and transmission because of similarities to humans in the distribution of HA receptors and in clinical signs of infection. In this study, we developed a ferret tracheal differentiated primary epithelial cell culture model that consisted of a layered epithelium structure with ciliated and nonciliated cells on its apical surface. We found that human-like (α2,6-linked) receptors predominated on ciliated cells, whereas avian-like (α2,3-linked) receptors, which were less abundant, were presented on nonciliated cells. When we compared the tropism and infectivity of three human (H1 and H3) and two avian (H1 and H5) influenza viruses, we observed that the human influenza viruses primarily infected ciliated cells and replicated efficiently, whereas a highly pathogenic avian H5N1 virus (A/Vietnam/1203/2004) replicated efficiently within nonciliated cells despite a low initial infection rate. Furthermore, compared to other influenza viruses tested, VN/1203 virus replicated more efficiently in cells isolated from the lower trachea and at a higher temperature (37°C) compared to a lower temperature (33°C). VN/1203 virus infection also induced higher levels of immune mediator genes and cell death, and virus was recovered from the basolateral side of the cell monolayer. This ferret tracheal differentiated primary epithelial cell culture system provides a valuable in vitro model for studying cellular tropism, infectivity, and the pathogenesis of influenza viruses. PMID:23255802

  19. Ecology and conservation biology of avian malaria

    National Research Council Canada - National Science Library

    LaPointe, Dennis A; Atkinson, Carter T; Samuel, Michael D

    2012-01-01

    .... Although vector habitat and avian communities determine the geographic distribution of disease, climate drives transmission patterns ranging from continuous high infection in warm lowland forests...

  20. Protective effects of pidotimod against experimental bacterial infections in mice.

    Science.gov (United States)

    Coppi, G; Falcone, A; Manzardo, S

    1994-12-01

    Pidotimod ((R)-3-[(S)-(5-oxo-2-pyrrolidinyl) carbonyl]-thiazolidine-4-carboxylic acid, PGT/1A, CAS 121808-62-6) protected mice against experimental bacterial infections in different experimental models. In all tests the drug's effect was measured as protection from death. The activity of pidotimod was evident and statistically significant after 5 administrations before the bacterial challenges. Pidotimod was active against many bacterial species infections, its active dosages ranging from 0.01 to 100 mg/kg i.p. x 5 times. Pidotimod showed against some bacterial infections a protection similar or better than those of bestatin, N-acetylmuramyl-L-Ala-D-isoGlu-OH and tuftsin. It showed high protection against bacterial infections in cyclophosphamide-immunodepressed mice. Finally, pidotimod showed an additive or synergic activity in combination with beta-lactam antibiotics (cefotaxime, ampicillin) against bacterial infections in mice.

  1. Avian necrotic enteritis: experimental models, host immunity, pathogenesis, risk factors, and vaccine development.

    Science.gov (United States)

    Lee, K W; Lillehoj, H S; Jeong, W; Jeoung, H Y; An, D J

    2011-07-01

    The increasing trends of legislative restrictions and voluntary removal of antibiotic growth promoters worldwide has already affected, and will continue to affect, poultry production and animal health. Necrotic enteritis (NE) is being considered among the most important infectious diseases in the current poultry production system globally, with an estimated annual economic loss of more than $2 billion, largely attributable to medical treatments and impaired growth performance. Thus, there is an urgent need to develop rational, alternative, and integrated management strategies not only to control NE, but also to prevent it. In both humans and many warm-blooded animals and birds, NE is caused by Clostridium perfringens, a gram-positive, anaerobic, spore-forming bacterium. To accomplish these goals, better understanding of host- and environmentally related factors on the development of NE and potential vaccination strategies against C. perfringens infection will be necessary. Furthermore, a reliable and reproducible NE disease model is needed for characterization of C. perfringens pathogenesis and host protective immunity. This review summarizes recent developments in NE disease models, pathogenesis, host immunity, risk factors, and vaccine development for C. perfringens-associated NE in poultry.

  2. Theorical and experimental model for carbon-13 turnover in mammalian and avian tissues

    OpenAIRE

    Ducatti Carlos; Carrijo Alfredo Sampaio; Pezzato Antônio Celso; Mancera Paulo Fernando de Arruda

    2002-01-01

    A diferença entre fontes alimentares da ordem de 14‰, originárias de plantas com ciclos fotossintéticos Carbono-3 (C3) e Carbono-4 (C4) e seus subprodutos, abre novas perspectivas para o estudo do metabolismo do carbono em aves e animais de pequeno porte. Os autores propõem um modelo teórico e experimental capaz de exprimir os resultados de enriquecimento relativo, delta per mil (delta‰) da razão 13C/12C versus tempo em diferentes tecidos. Utilizou-se a equação y(t) = (y0 -- q/k) e-kt + q/k o...

  3. Avian And Other Zoonotic Influenza

    Science.gov (United States)

    ... sheets Fact files Questions & answers Features Multimedia Contacts Influenza (Avian and other zoonotic) Fact sheet Reviewed January ... known to infect or cause illness in people. Influenza type A viruses are of most significance to ...

  4. Avian anemia's

    OpenAIRE

    Raukar Jelena

    2005-01-01

    This paper deals with avian anemia's classified by MCHC/MCV and with types of anemia's. Father hematological and immunological research is needed to secure information on hematological parameters in different avian species at their earliest age. Anemia is a common clinical finding in birds because the avian erythrocyte half - life is much shorter than the mammalian. Therefore anemia should be determined as soon as possible. Researchers should standardize hematologica...

  5. Experimental rhinovirus infection in COPD: implications for antiviral therapies.

    Science.gov (United States)

    Gunawardana, Natasha; Finney, Lydia; Johnston, Sebastian L; Mallia, Patrick

    2014-02-01

    Chronic obstructive pulmonary disease (COPD) is a major public health problem and will be one of the leading global causes of mortality over the coming decades. Much of the morbidity, mortality and health care costs of COPD are attributable to acute exacerbations, the commonest causes of which are respiratory infections. Respiratory viruses are frequently detected in COPD exacerbations but direct proof of a causative relationship has been lacking. We have developed a model of COPD exacerbation using experimental rhinovirus infection in COPD patients and this has established a causative relationship between virus infection and exacerbations. In addition it has determined some of the molecular mechanisms linking virus infections to COPD exacerbations and identified potential new therapeutic targets. This new data should stimulate research into the role of antiviral agents as potential treatments for COPD exacerbations. Testing of antiviral agents has been hampered by the lack of a small animal model for rhinovirus infection and experimental rhinovirus infection in healthy volunteers has been used to test treatments for the common cold. Experimental rhinovirus infection in COPD subjects offers the prospect of a model that can be used to evaluate the effects of new treatments for virus-induced COPD exacerbations, and provide essential data that can be used in making decisions regarding large scale clinical trials. Copyright © 2014 Elsevier B.V. All rights reserved.

  6. [Avian pathogenic Escherichia coli (APEC)].

    Science.gov (United States)

    Ewers, Christa; Janssen, Traute; Wieler, Lothar H

    2003-01-01

    and the resistance to the bactericidal effects of serum, predominantly conferred by the increased serum survival (iss)--protein, enables APEC to multiply quickly in their hosts. Iss is regarded a specific genetic marker for avian pathogenic E. colistrains. A critical review of the literature published so far on APEC reveals, that these pathotypes are not defined appropriately. This findings urge investigations on the population structure of APEC, enabling the establishment of appropriate diagnostic tools and avoiding the obsolete use of serotyping for APEC diagnosis. So far more than 20 APEC strains have been investigated in animal experiments, explaining contrary published results. Thus, the lack of knowledge in pathogenicity and in immunity of APEC infections urges further experimental studies. As APEC share not only identical serotypes with human pathogens but also specific virulence factors, their zoonotic potential is under consideration.

  7. Global Emerging Infection Surveillance and Response (GEIS)- Avian Influenza Pandemic Influenza (AI/PI) Program

    Science.gov (United States)

    2010-10-01

    specimens and Brucellosis in 0.2%. All brucella positive samples came from a hospital that serves the nomadic population. Leptospirosis and Dengue have...those that have the potential to be exploited as biothreat. Limited epidemiological data, blood and nasal pharyngeal swabs are collected from patients...Silvanos Mukunzi, Denis Mwala and David C. Schnabel. Human parainfluenza virus infections in kenya: epidemiologic aspects. Africa Influenza

  8. Origin and characteristics of internal genes affect infectivity of the novel avian-origin influenza A (H7N9) virus.

    Science.gov (United States)

    Feng, Yan; Mao, Haiyan; Xu, Changping; Jiang, Jianmin; Chen, Yin; Yan, Juying; Gao, Jian; Li, Zhen; Xia, Shichang; Lu, Yiyu

    2013-01-01

    Human infection with a novel avian-origin influenza A (H7N9) virus occurred continuously in China during the first half of 2013, with high infectivity and pathogenicity to humans. In this study, we investigated the origin of internal genes of the novel H7N9 virus and analyzed the relationship between internal genes and infectivity of the virus. We tested the environmental specimens using real-time RT-PCR assays and isolated five H9N2 viruses from specimens that were positive for both H7 and H9. Results of recombination and phylogeny analysis, performed based on the entire sequences of 221 influenza viruses, showed that one of the Zhejiang avian H9N2 isolates, A/environment/Zhejiang/16/2013, shared the highest identities on the internal genes with the novel H7N9 virus A/Anhui/1/2013, ranging from 98.98% to 100%. Zhejiang avian H9N2 isolates were all reassortant viruses, by acquiring NS gene from A/chicken/Dawang/1/2011-like viruses and other five internal genes from A/brambling/Beijing/16/2012-like viruses. Compared to A/Anhui/1/2013 (H7N9), the homology on the NS gene was 99.16% with A/chicken/Dawang/1/2011, whereas only 94.27-97.61% with A/bramnling/Beijing/16/2012-like viruses. Analysis on the relationship between internal genes and the infectivity of novel H7N9 viruses were performed by comparing amino acid sequences with the HPAI H5N1 viruses, the H9N2 and the earlier H7N9 avian influenza viruses. There were nine amino acids on the internal genes found to be possibly associated with the infectivity of the novel H7N9 viruses. These findings indicate that the internal genes, sharing the highest similarities with A/environment/Zhejiang/16/2013-like (H9N2) viruses, may affect the infectivity of the novel H7N9 viruses.

  9. Kinetic Characterization of PB1-F2-Mediated Immunopathology during Highly Pathogenic Avian H5N1 Influenza Virus Infection

    Science.gov (United States)

    Leymarie, Olivier; Jouvion, Grégory; Hervé, Pierre-Louis; Chevalier, Christophe; Lorin, Valérie; Lecardonnel, Jérôme; Da Costa, Bruno; Delmas, Bernard

    2013-01-01

    The PB1-F2 protein encoded by influenza A viruses can contribute to virulence, a feature that is dependent of its sequence polymorphism. Whereas PB1-F2 from some H1N1 viruses were shown to exacerbate the inflammatory response within the airways, the contribution of PB1-F2 to highly pathogenic avian influenza virus (HPAIV) virulence in mammals remains poorly described. Using a H5N1 HPAIV strain isolated from duck and its PB1-F2 knocked-out mutant, we characterized the dynamics of PB1-F2-associated host response in a murine model of lethal pneumonia. The mean time of death was 10 days for the two viruses, allowing us to perform global transcriptomic analyses and detailed histological investigations of the infected lungs at multiple time points. At day 2 post-infection (pi), while no histopathological lesion was observed, PB1-F2 expression resulted in a significant inhibition of cellular pathways involved in macrophage activation and in a transcriptomic signature suggesting that it promotes damage to the epithelial barrier. At day 4 pi, the gene profile associated with PB1-F2 expression revealed dysfunctions in NK cells activity. At day 8 pi, PB1-F2 expression was strongly associated with increased transcription of genes encoding chemokines and cytokines implicated in the recruitment of granulocytes, as well as expression of a number of genes encoding enzymes expressed by neutrophils. These transcriptomic data were fully supported by the histopathological analysis of the mice lungs which evidenced more severe inflammatory lesions and enhanced recruitment of neutrophils in the context of PB1-F2 expression, and thus provided a functional corroboration to the insight obtained in this work. In summary, our study shows that PB1-F2 of H5N1 HPAIV markedly influences the expression of the host transcriptome in a different way than its H1N1 counterparts: H5N1 PB1-F2 first delays the initial immune response but increases the pulmonary inflammatory response during the late

  10. Avian influenza viruses that cause highly virulent infections in humans exhibit distinct replicative properties in contrast to human H1N1 viruses

    Science.gov (United States)

    Simon, Philippe F.; de La Vega, Marc-Antoine; Paradis, Éric; Mendoza, Emelissa; Coombs, Kevin M.; Kobasa, Darwyn; Beauchemin, Catherine A. A.

    2016-04-01

    Avian influenza viruses present an emerging epidemiological concern as some strains of H5N1 avian influenza can cause severe infections in humans with lethality rates of up to 60%. These have been in circulation since 1997 and recently a novel H7N9-subtyped virus has been causing epizootics in China with lethality rates around 20%. To better understand the replication kinetics of these viruses, we combined several extensive viral kinetics experiments with mathematical modelling of in vitro infections in human A549 cells. We extracted fundamental replication parameters revealing that, while both the H5N1 and H7N9 viruses replicate faster and to higher titers than two low-pathogenicity H1N1 strains, they accomplish this via different mechanisms. While the H7N9 virions exhibit a faster rate of infection, the H5N1 virions are produced at a higher rate. Of the two H1N1 strains studied, the 2009 pandemic H1N1 strain exhibits the longest eclipse phase, possibly indicative of a less effective neuraminidase activity, but causes infection more rapidly than the seasonal strain. This explains, in part, the pandemic strain’s generally slower growth kinetics and permissiveness to accept mutations causing neuraminidase inhibitor resistance without significant loss in fitness. Our results highlight differential growth properties of H1N1, H5N1 and H7N9 influenza viruses.

  11. Protocatechuic acid, a novel active substance against avian influenza virus H9N2 infection.

    Directory of Open Access Journals (Sweden)

    Changbo Ou

    Full Text Available Influenza virus H9N2 subtype has triggered co-infection with other infectious agents, resulting in huge economical losses in the poultry industry. Our current study aims to evaluate the antiviral activity of protocatechuic acid (PCA against a virulent H9N2 strain in a mouse model. 120 BALB/c mice were divided into one control group, one untreated group, one 50 mg/kg amantadine hydrochloride-treated group and three PCA groups treated 12 hours post-inoculation with 40, 20 or 10 mg/kg PCA for 7 days. All the infected animals were inoculated intranasally with 0.2 ml of a A/Chicken/Hebei/4/2008(H9N2 inoculum. A significant body weight loss was found in the 20 mg/kg and 40 mg/kg PCA-treated and amantadine groups as compared to the control group. The 14 day survivals were 94.4%, 100% and 95% in the PCA-treated groups and 94.4% in the amantadine hydrochloride group, compared to less than 60% in the untreated group. Virus loads were less in the PCA-treated groups compared to the amantadine-treated or the untreated groups. Neutrophil cells in BALF were significantly decreased while IFN-γ, IL-2, TNF-α and IL-6 decreased significantly at days 7 in the PCA-treated groups compared to the untreated group. Furthermore, a significantly decreased CD4+/CD8+ ratio and an increased proportion of CD19 cells were observed in the PCA-treated groups and amantadine-treated group compared to the untreated group. Mice administered with PCA exhibited a higher survival rate and greater viral clearance associated with an inhibition of inflammatory cytokines and activation of CD8+ T cell subsets. PCA is a promising novel agent against bird flu infection in the poultry industry.

  12. Clinical characteristics of 26 human cases of highly pathogenic avian influenza A (H5N1 virus infection in China.

    Directory of Open Access Journals (Sweden)

    Hongjie Yu

    Full Text Available BACKGROUND: While human cases of highly pathogenic avian influenza A (H5N1 virus infection continue to increase globally, available clinical data on H5N1 cases are limited. We conducted a retrospective study of 26 confirmed human H5N1 cases identified through surveillance in China from October 2005 through April 2008. METHODOLOGY/PRINCIPAL FINDINGS: Data were collected from hospital medical records of H5N1 cases and analyzed. The median age was 29 years (range 6-62 and 58% were female. Many H5N1 cases reported fever (92% and cough (58% at illness onset, and had lower respiratory findings of tachypnea and dyspnea at admission. All cases progressed rapidly to bilateral pneumonia. Clinical complications included acute respiratory distress syndrome (ARDS, 81%, cardiac failure (50%, elevated aminotransaminases (43%, and renal dysfunction (17%. Fatal cases had a lower median nadir platelet count (64.5 x 10(9 cells/L vs 93.0 x 10(9 cells/L, p = 0.02, higher median peak lactic dehydrogenase (LDH level (1982.5 U/L vs 1230.0 U/L, p = 0.001, higher percentage of ARDS (94% [n = 16] vs 56% [n = 5], p = 0.034 and more frequent cardiac failure (71% [n = 12] vs 11% [n = 1], p = 0.011 than nonfatal cases. A higher proportion of patients who received antiviral drugs survived compared to untreated (67% [8/12] vs 7% [1/14], p = 0.003. CONCLUSIONS/SIGNIFICANCE: The clinical course of Chinese H5N1 cases is characterized by fever and cough initially, with rapid progression to lower respiratory disease. Decreased platelet count, elevated LDH level, ARDS and cardiac failure were associated with fatal outcomes. Clinical management of H5N1 cases should be standardized in China to include early antiviral treatment for suspected H5N1 cases.

  13. [Avian influenza virus infection in people occupied in poultry fields in Guangzhou city].

    Science.gov (United States)

    Liu, Yang; Lu, En-jie; Wang, Yu-lin; Di, Biao; Li, Tie-gang; Zhou, Yong; Yang, Li-li; Xu, Xiao-yin; Fu, Chuan-xi; Wang, Ming

    2009-11-01

    To conduct serological investigation on H5N1/H9N2/H7N7 infection among people occupied in poultry fields. Serum samples were collected from people working in live poultry and none-poultry retailing food markets, poultry wholesaling, large-scale poultry breading factories and in small-scale farms, wide birds breeding, swine slaughtering houses and from normal population. Antibodies of H5, H9 and H7 with hemagglutination inhibition and neutralization tests were tested and analyzed. Logistic regression and chi(2) test were used. Among 2881 samples, 4 were positive to H5-Ab (0.14%), 146 were positive to H9-Ab (5.07%) and the prevalence of H9 among people from live poultry retailing (14.96%) was the highest. Prevalence rates of H9 were as follows: 8.90% in people working in the large-scale poultry breading factories, 6.69% in the live poultry wholesaling business, 3.75% in the wide birds breeding, 2.40% in the swine slaughtering, 2.21% in the non-poultry retailing, 1.77% in the rural poultry farmers and 2.30% in normal population. None was positive to H7-Ab among 1926 poultry workers. The H5 prevalence among people was much lower than expected, but the H9 prevalence was higher. None of the populations tested was found positive to H7-Ab. There was a higher risk of AIV infection in live poultry retailing, wholesaling and large-scale breading businesses, with the risk of live poultry retailing the highest. The longer the service length was, the higher the risk existed.

  14. 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...

  15. Administration of Poly[di(sodium carboxylatoethylphenoxy)phosphazene] (PCEP) and Avian Beta Defensin as Adjuvants in Inactivated Inclusion Body Hepatitis Virus and its Hexon Protein-Based Experimental Vaccine Formulations in Chickens.

    Science.gov (United States)

    Dar, Arshud; Tipu, Masroor; Townsend, Hugh; Potter, Andy; Gerdts, Volker; Tikoo, Suresh

    2015-12-01

    Inclusion body hepatitis (IBH) is one of the major infectious diseases adversely affecting the poultry industry of the United States and Canada. Currently, no effective and safe vaccine is available for the control of IBH virus (IBHV) infection in chickens. However, based on the excellent safety and immunogenic profiles of experimental veterinary vaccines developed with the use of new generation adjuvants, we hypothesized that characterization of vaccine formulations containing inactivated IBHV or its capsid protein hexon as antigens, along with poly[di(sodium carboxylatoethylphenoxy)phosphazene] (PCEP) and avian beta defensin 2 (ABD2) as vaccine adjuvants, will be helpful in development of an effective and safe vaccine formulation for IBH. Our data demonstrated that experimental administration of vaccine formulations containing inactivated IBHV and a mixture of PCEP with or without ABD2 as an adjuvant induced significantly higher antibody responses compared with other vaccine formulations, while hexon protein-based vaccine formulations showed relatively lower levels of antibody responses. Thus, a vaccine formulation containing inactivated IBHV with PCEP or a mixture of PCEP and ABD2 (with a reduced dosage of PCEP) as an adjuvant may serve as a potential vaccine candidate. However, in order to overcome the risks associated with whole virus inactivated vaccines, characterization of additional viral capsid proteins, including fiber protein and penton of IBHV along with hexon protein in combination with more new generation adjuvants, will be helpful in further improvements of vaccines against IBHV infection.

  16. Deciphering alternative splicing and nonsense-mediated decay modulate expression in primary lymphoid tissues of birds infected with avian pathogenic E. coli (APEC).

    Science.gov (United States)

    Sun, Hongyan

    2017-03-07

    Avian pathogenic E. coli (APEC) can lead to a loss in millions of dollars in poultry annually because of mortality and produce contamination. Studies have verified that many immune-related genes undergo changes in alternative splicing (AS), along with nonsense mediated decay (NMD), to regulate the immune system under different conditions. Therefore, the splicing profiles of primary lymphoid tissues with systemic APEC infection need to be comprehensively examined. Gene expression in RNAseq data were obtained for three different immune tissues (bone marrow, thymus, and bursa) from three phenotype birds (non-challenged, resistant, and susceptible birds) at two time points. Alternative 5' splice sites and exon skipping/inclusion were identified as the major alternative splicing events in avian primary immune organs under systemic APEC infection. In this study, we detected hundreds of differentially-expressed-transcript-containing genes (DETs) between different phenotype birds at 5 days post-infection (dpi). DETs, PSAP and STT3A, with NMD have important functions under systemic APEC infection. DETs, CDC45, CDK1, RAG2, POLR1B, PSAP, and DNASE1L3, from the same transcription start sites (TSS) indicate that cell death, cell cycle, cellular function, and maintenance were predominant in host under systemic APEC. With the use of RNAseq technology and bioinformatics tools, this study provides a portrait of the AS event and NMD in primary lymphoid tissues, which play critical roles in host homeostasis under systemic APEC infection. According to this study, AS plays a pivotal regulatory role in the immune response in chicken under systemic APEC infection via either NMD or alternative TSSs. This study elucidates the regulatory role of AS for the immune complex under systemic APEC infection.

  17. Demographic and Spatiotemporal Patterns of Avian Influenza Infection at the Continental Scale, and in Relation to Annual Life Cycle of a Migratory Host.

    Directory of Open Access Journals (Sweden)

    Rodolfo Nallar

    Full Text Available Since the spread of highly pathogenic avian influenza (HPAI H5N1 in the eastern hemisphere, numerous surveillance programs and studies have been undertaken to detect the occurrence, distribution, or spread of avian influenza viruses (AIV in wild bird populations worldwide. To identify demographic determinants and spatiotemporal patterns of AIV infection in long distance migratory waterfowl in North America, we fitted generalized linear models with binominal distribution to analyze results from 13,574 blue-winged teal (Anas discors, BWTE sampled in 2007 to 2010 year round during AIV surveillance programs in Canada and the United States. Our analyses revealed that during late summer staging (July-August and fall migration (September-October, hatch year (HY birds were more likely to be infected than after hatch year (AHY birds, however there was no difference between age categories for the remainder of the year (winter, spring migration, and breeding period, likely due to maturing immune systems and newly acquired immunity of HY birds. Probability of infection increased non-linearly with latitude, and was highest in late summer prior to fall migration when densities of birds and the proportion of susceptible HY birds in the population are highest. Birds in the Central and Mississippi flyways were more likely to be infected compared to those in the Atlantic flyway. Seasonal cycles and spatial variation of AIV infection were largely driven by the dynamics of AIV infection in HY birds, which had more prominent cycles and spatial variation in infection compared to AHY birds. Our results demonstrate demographic as well as seasonal, latitudinal and flyway trends across Canada and the US, while illustrating the importance of migratory host life cycle and age in driving cyclical patterns of prevalence.

  18. Quantification of bird-to-bird and bird-to-human infections during 2013 novel H7N9 avian influenza outbreak in China.

    Science.gov (United States)

    Hsieh, Ying-Hen; Wu, Jianhong; Fang, Jian; Yang, Yong; Lou, Jie

    2014-01-01

    From February to May, 2013, 132 human avian influenza H7N9 cases were identified in China resulting in 37 deaths. We developed a novel, simple and effective compartmental modeling framework for transmissions among (wild and domestic) birds as well as from birds to human, to infer important epidemiological quantifiers, such as basic reproduction number for bird epidemic, bird-to-human infection rate and turning points of the epidemics, for the epidemic via human H7N9 case onset data and to acquire useful information regarding the bird-to-human transmission dynamics. Estimated basic reproduction number for infections among birds is 4.10 and the mean daily number of human infections per infected bird is 3.16*10-5 [3.08*10-5, 3.23*10-5]. The turning point of 2013 H7N9 epidemic is pinpointed at April 16 for bird infections and at April 9 for bird-to-human transmissions. Our result reveals very low level of bird-to-human infections, thus indicating minimal risk of widespread bird-to-human infections of H7N9 virus during the outbreak. Moreover, the turning point of the human epidemic, pinpointed at shortly after the implementation of full-scale control and intervention measures initiated in early April, further highlights the impact of timely actions on ending the outbreak. This is the first study where both the bird and human components of an avian influenza epidemic can be quantified using only the human case data.

  19. Demographic and spatiotemporal patterns of avian influenza infection at the continental scale, and in relation to annual life cycle of a migratory host

    Science.gov (United States)

    Nallar, Rodolfo; Papp, Zsuzsanna; Epp, Tasha; Leighton, Frederick A.; Swafford, Seth R.; DeLiberto, Thomas J.; Dusek, Robert J.; Ip, Hon S.; Hall, Jeffrey S.; Berhane, Yohannes; Gibbs, Samantha E.J.; Soos, Catherine

    2015-01-01

    Since the spread of highly pathogenic avian influenza (HPAI) H5N1 in the eastern hemisphere, numerous surveillance programs and studies have been undertaken to detect the occurrence, distribution, or spread of avian influenza viruses (AIV) in wild bird populations worldwide. To identify demographic determinants and spatiotemporal patterns of AIV infection in long distance migratory waterfowl in North America, we fitted generalized linear models with binominal distribution to analyze results from 13,574 blue-winged teal (Anas discors, BWTE) sampled in 2007 to 2010 year round during AIV surveillance programs in Canada and the United States. Our analyses revealed that during late summer staging (July-August) and fall migration (September-October), hatch year (HY) birds were more likely to be infected than after hatch year (AHY) birds, however there was no difference between age categories for the remainder of the year (winter, spring migration, and breeding period), likely due to maturing immune systems and newly acquired immunity of HY birds. Probability of infection increased non-linearly with latitude, and was highest in late summer prior to fall migration when densities of birds and the proportion of susceptible HY birds in the population are highest. Birds in the Central and Mississippi flyways were more likely to be infected compared to those in the Atlantic flyway. Seasonal cycles and spatial variation of AIV infection were largely driven by the dynamics of AIV infection in HY birds, which had more prominent cycles and spatial variation in infection compared to AHY birds. Our results demonstrate demographic as well as seasonal, latitudinal and flyway trends across Canada and the US, while illustrating the importance of migratory host life cycle and age in driving cyclical patterns of prevalence.

  20. Expression pattern of NLRP3 and its related cytokines in the lung and brain of avian influenza virus H9N2 infected BALB/c mice.

    Science.gov (United States)

    Yu, Meng; Zhang, Kaizhao; Qi, Wenbao; Huang, Zhiqiang; Ye, Jinhui; Ma, Yongjiang; Liao, Ming; Ning, Zhangyong

    2014-12-30

    H9N2 avian influenza virus (AIV) becomes the focus for its ability of transmission to mammals and as a donor to provide internal genes to form the new epidemic lethal influenza viruses. Residue 627 in PB2 has been proven the virulence factor of H9N2 avian influenza virus in mice, but the detailed data for inflammation difference between H9N2 virus strains with site 627 mutation is still unclear. The inflammasome NLRP3 is recently reported as the cellular machinery responsible for activation of inflammatory processes and plays an important role during the development of inflammation caused by influenza virus infection. In this study, we investigated the expression pattern of NLRP3 and its related cytokines of IL-1β and TNF-α in BALB/c mice infected by H9N2 AIV strains with only a site 627 difference at both mRNA and protein levels at different time points. The results showed that the expression level of NLRP3, IL-1β and TNF-α changed in the lung and brain of BALB/c mice after infection by VK627 and rVK627E. The immunohistological results showed that the positive cells of NLRP3, IL-1β and TNF-α altered the positive levels of original cells in tissues and infiltrated inflammatory cells which caused by H9N2 infection. Our results provided the basic data at differences in expression pattern of NLRP3 and its related cytokines in BALB/c mice infected by H9N2 influenza viruses with only a site 627 difference. This implied that NLRP3 inflammasome plays a role in host response to influenza virus infection and determines the outcome of clinical manifestation and pathological injury. This will explain the variable of pathological presentation in tissues and enhance research on inflammation process of the AIV H9N2 infection.

  1. Experimental Theileria lestoquardi infection in sheep: Biochemical and hematological changes.

    Science.gov (United States)

    Yaghfoori, Saeed; Mohri, Mehrdad; Razmi, Gholamreza

    2017-09-01

    Malignant theileriosis (Theileria lestoquardi infection) is a hemoparasitic tick-borne disease that affects both wild and domestic small ruminants. The aim of this study was to evaluate biochemical and hematological characteristics of sheep after being experimentally infected by T. lestoquardi. T. lestoquardi infection was induced in seven Baluchi sheep of six-to-eight months old via experimentally-infected Hyalomma anatolicum adult ticks. Biochemical and hematological parameters were measured twice a week during the three weeks' post infection. Twenty-three biochemical analytes and seven hematological ones were measured. After three to four days infection, body temperature rose above 40(°)C. Maximum and minimum parasitaemia were 3.3% and 0.28%, respectively. Piroplasms and schizont were seen on average from days 7.2 and 4 post infection, respectively. The concentrations and activities of Alb, HDL, ALT, T3, T4, Ca, Fe, Mg, iP, WBC, RBC, PCV, Hb, Plt, neutrophil and lymphocytes significantly decreased (P≤0.05) during experimental infection. However, concentrations and activities of BT, GGT, Glu, BUN, Crea, FIB and Cu significantly increased (P≤0.05). There was no significant change in the serum amounts of Chol, LDL, TG, VLDL and Zn. The observed hypoalbuminemia and increase of FIB concentrations referred to pro-inflammatory cytokines production. Moreover, the raising of GGT activity indicates liver damage, cholestatic disorders or schizont infiltration. The disease stress and corticosteroids are suspected to cause the Glu concentration increase. The present study is aimed at improving the knowledge of malignant theileriosis. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. Nocardia brasiliensis: from microbe to human and experimental infections.

    Science.gov (United States)

    Salinas-Carmona, M C

    2000-09-01

    Nocardia brasiliensis is a Gram-positive bacterium that lives as a saprophyte in soil. In this article the physical properties, chemical composition and taxonomic position of this species is reviewed. Human infections and an experimental model of actinomycetoma in BALB/c mice as well as the host-immune response is described.

  3. Cutaneous and diphtheritic avian poxvirus infection in a nestling Southern Giant Petrel (Macronectes giganteus) from Antarctica

    Science.gov (United States)

    Shearn-Bochsler, Valerie; Green, David Earl; Converse, K.A.; Docherty, D.E.; Thiel, T.; Geisz, H.N.; Fraser, William R.; Patterson-Fraser, Donna L.

    2008-01-01

    The Southern giant petrel (Macronectes giganteus) is declining over much of its range and currently is listed as vulnerable to extinction by the International Union for the Conservation of Nature (IUCN). Island-specific breeding colonies near Palmer Station, Antarctica, have been monitored for over 30 years, and because this population continues to increase, it is critically important to conservation. In austral summer 2004, six diseased giant petrel chicks were observed in four of these colonies. Diseased chicks were 6a??9 weeks old and had multiple proliferative nodules on their bills and skin. One severely affected chick was found dead on the nest and was salvaged for necropsy. Histopathological examination of nodules from the dead chick revealed epithelial cell hyperplasia and hypertrophy with numerous eosinophilic intracytoplasmic inclusions (B??llinger bodies). A poxvirus was isolated from multiple nodules. Poxviral infection has not been reported in this species, and the reason for its emergence and its potential impact on the population are not yet known.

  4. Avian Haemosporidian blood parasite infections at a migration hotspot in Eilat, Israel

    Directory of Open Access Journals (Sweden)

    Paperna Ilan

    2016-06-01

    Full Text Available Haemosporidian blood parasites are frequent amongst passerines. Though they often do not cause detectable consequences to host health, however, their presence or absence and also their prevalence across host populations may potentially carry meaningful information about the health, stress, body condition and viability of bird individuals or populations. The study of migratory birds captured in Eilat, Israel, allowed us to evaluate the prevalence of blood parasite infections in a wide range of both migrant and resident species in spring (N = 1,950 and autumn (N = 538 of 2004 and 2005. According to blood film microscopy, Haemoproteus spp. and Leucocytozoon spp. were more prevalent in the spring than in the autumn (0.289, 0.082 vs. 0.132, 0.033, respectively, whilst Plasmodium spp. exhibited a slight opposite trend (0.034, 0.056. All other parasites (such as trypanosomes, microfilaria and haemococcidians were rare. During the spring seasons, prevalences were significantly higher in migrant than in resident species, whilst this difference was only marginally significant in the autumn. Given that Eilat is a migration hotspot for several Palearctic passerine species, the present descriptive study may hopefully serve to set the baseline values for future long-term epidemiological monitoring.

  5. 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.

  6. DNA microarray-mediated transcriptional profiling of avian pathogenic Escherichia coli O2 strain E058 during its infection of chicken.

    Science.gov (United States)

    Gao, Qingqing; Xia, Le; Liu, Juanhua; Wang, Xiaobo; Gao, Song; Liu, Xiufan

    2016-11-01

    Avian pathogenic Escherichia coli (APEC) cause typical extraintestinal infections in poultry, including acute fatal septicemia, subacute pericarditis, and airsacculitis. These bacteria most often infect chickens, turkeys, ducks, and other avian species, and therefore pose a significant economic burden on the poultry industry worldwide. Few studies have analyzed the genome-wide transcriptional profile of APEC during infection in vivo. In this study, we examined the genome-wide transcriptional response of APEC O2 strain E058 in an in vivo chicken infection model to better understand the factors necessary for APEC colonization, growth, and survival in vivo. An Affymetrix multigenome DNA microarray, which contains most of the genomic open reading frames of E. coli K-12 strain MG1655, uropathogenic E. coli strain CFT073, and E. coli O157:H7 strain EDL 933, was used to profile the gene expression in APEC E058. We identified the in vivo transcriptional response of APEC E058 bacteria collected directly from the blood of infected chickens. Significant differences in expression levels were detected between the in vivo expression profile and the in vitro expression profile in LB medium. The genes highly expressed during infection were involved in metabolism, iron acquisition or transport, virulence, response to stress, and biological regulation. The reliability of the microarray data was confirmed by performing quantitative real-time PCR on 12 representative genes. Moreover, several significantly upregulated genes, including yjiY, sodA, phoB and spy, were selected to study their role in APEC pathogenesis. The data will help to better understand the mechanisms of APEC pathogenesis. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. A detailed epidemiological and clinical description of 6 human cases of avian-origin influenza A (H7N9 virus infection in Shanghai.

    Directory of Open Access Journals (Sweden)

    Jindong Shi

    Full Text Available BACKGROUND: The world's first reported patient infected with avian influenza H7N9 was treated at the Fifth People's Hospital of Shanghai. Shortly thereafter, several other cases emerged in the local area. Here, we describe the detailed epidemiological and clinical data of 6 cases of avian influenza H7N9. METHODS AND FINDINGS: We analyzed the epidemiologic and clinical data from clustered patients infected with H7N9 in the Minhang District of Shanghai during a 2-week period. Of the 6 patients, 2 were from a single family. In addition, 3 patients had a history of contact with poultry; however, all 6 patients lived in the proximity of 2 food markets where the H7N9 virus was detected in chickens and pigeons. The main symptoms were fever, cough, and hemoptysis. At onset, a decreased lymphocyte count and elevated creatine kinase, lactate dehydrogenase, procalcitonin, and C-reactive protein levels were observed. As the disease progressed, most patients developed dyspnea and hypoxemia. Imaging studies revealed lung consolidation and multiple ground-glass opacities in the early stage, rapidly extending bilaterally. All patients were treated with oseltamivir tablets beginning on days 3-8 after onset. The main complications were as follows: acute respiratory distress syndrome (ARDS; 83.3%, secondary bacterial infection (66.7%, pleural effusion (50%, left ventricular failure (33.3%, neuropsychiatric symptoms (33.3%, and rhabdomyolysis (16.7%. Of the 6 patients, 4 died of ARDS, with 2 patients recovering from the infection. CONCLUSIONS: An outbreak of H7N9 infection occurred in the Minhang District of Shanghai that easily progressed to acute respiratory distress syndrome. Two cases showed family aggregation, which led us to identify the H7N9 virus and indicated that human transmission may be involved in the spread of this infection.

  8. Ocular pathological changes in hamsters experimentally infected with Schistosoma mansoni.

    Science.gov (United States)

    Ismail, H I H; Ashour, D S; Abou Rayia, D M; Ali, A L

    2016-11-01

    Ocular lesions have been reported in patients with schistosomiasis; however, the problem with studying schistosomal infection of the human eye is that biopsies are almost impossible to take, and histopathological examination of suspicious lesions can only be undertaken post-mortem or after enucleation. This work aimed to study the possible effects and pathogenesis of schistosomiasis on the eye. This study involved 55 hamsters; five hamsters remained non-infected and the remaining 50 hamsters were infected with Schistosoma mansoni cercariae. Infected hamsters were sacrificed on weeks 8, 12, 16 and 20 post-infection (pi). Eye sections were prepared and stained for histopathological and immunohistochemical studies. Histopathological changes detected in hamsters infected after 16 and 20 weeks included looseness and oedema of the innermost retinal layers together with hyperplastic polypoid growth. Neither eggs nor granulomata were detected in eye sections throughout the experimental period. Deposition of S. mansoni antigen was revealed in 35% of infected hamsters. Later, on weeks 16 and 20 pi, moderate subepithelial conjuctival deposits and marked subchoroidal and scleral deposition were detected. In conclusion, the deposition of schistosomal antigen and immune complexes may play a pivotal role in the ocular changes that occur in schistosomiasis, even in the absence of detectable Schistosoma eggs. Schistosomiasis should be suspected in cases with unexplained ophthalmological findings, especially in endemic areas.

  9. Differentially expressed genes in a flock of Chinese local-breed chickens infected with a subgroup J avian leukosis virus using suppression subtractive hybridization

    Directory of Open Access Journals (Sweden)

    Guiping Zhao

    2010-01-01

    Full Text Available Avian leukosis virus subgroup J (ALV-J is a new type of virus that mainly induces myeloid leukosis (ML in chickens. To further elucidate the pathogenesis of ALV-J infection and tumor development, expression profiles from the bone marrow tissue of 15 infected and 18 non-infected birds from a local-breed poultry-farm under naturally infected conditions, were analyzed by suppression-subtractive hybridization. The birds were diagnosed as ML+ (or ML- by specific ALV-J detection methods, involving serological tests for antigens and antibodies, and RT-PCR to detect viral RNA. A total of 59 partial gene sequences were revealed by differential screening of 496 forward and 384 reverse subtracted cDNA clones. Of these, 22 identified genes, including 8 up-regulated and 14 down-regulated, were related to immune functions, these genes being, MHC B-G antigen, translationally-controlled tumor protein (TPT1/TPTC, transferrin and ferritin, hemoglobin and Carbonic anhydrase. Four of the down-regulated genes were selected for further analysis, in view of their predicted roles in infection and immunity by real-time qRT-PCR, using RNA collected from the same birds as those used for SSH. The four genes were expressed at significantly lower levels (p < 0.001 in ALV-J infected birds than in non-infected ones.

  10. Differentially expressed genes in a flock of Chinese local-breed chickens infected with a subgroup J avian leukosis virus using suppression subtractive hybridization.

    Science.gov (United States)

    Zhao, Guiping; Zheng, Maiqing; Chen, Jilan; Wen, Jie; Wu, Chunmei; Li, Wenjuan; Liu, Libo; Zhang, Yuan

    2010-01-01

    Avian leukosis virus subgroup J (ALV-J) is a new type of virus that mainly induces myeloid leukosis (ML) in chickens. To further elucidate the pathogenesis of ALV-J infection and tumor development, expression profiles from the bone marrow tissue of 15 infected and 18 non-infected birds from a local-breed poultry-farm under naturally infected conditions, were analyzed by suppression-subtractive hybridization. The birds were diagnosed as ML+ (or ML-) by specific ALV-J detection methods, involving serological tests for antigens and antibodies, and RT-PCR to detect viral RNA. A total of 59 partial gene sequences were revealed by differential screening of 496 forward and 384 reverse subtracted cDNA clones. Of these, 22 identified genes, including 8 up-regulated and 14 down-regulated, were related to immune functions, these genes being, MHC B-G antigen, translationally-controlled tumor protein (TPT1/TPTC), transferrin and ferritin, hemoglobin and Carbonic anhydrase. Four of the down-regulated genes were selected for further analysis, in view of their predicted roles in infection and immunity by real-time qRT-PCR, using RNA collected from the same birds as those used for SSH. The four genes were expressed at significantly lower levels (p < 0.001) in ALV-J infected birds than in non-infected ones.

  11. Experimental model for Porphyromonas gingivalis infection in animals.

    Science.gov (United States)

    Eke, P I; Rotimi, V O; Laughon, B E

    1996-03-01

    A virulence model suitable for studying the dynamics of Porphyromonas gingivalis infection, including the pathogenicity of P. gingivalis in experimentally induced infections of multiple organs was developed using mouse and hamster. Virulence of P. gingivalis strains was expressed contrastingly in subcutaneous (sc) infection in the Murine abscess model (MAM) and the Hamsters abscess model (HAM). Subcutaneous infection in the MAM was characterized by a gravity abscess, spreading from the primary site of inoculation downwards, frequently erupting as a secondary lesion. In contract, s.c. P. gingivalis infection in HAM was characterized as a palpable localized abscess at the primary site of inoculation. When the Semi-Solid Agar (SSA) was added to the mono-culture of P. gingivalis, reproducibility of infection in both models was enhanced. P. gingivalis culture supplemented with haemin, or combined with oral Actinomyces viscosus had its virulence overtly enhanced and often fatal in the MAM. Menadione, Eh reducing agents and mixture with the Streptococcus or A. neaslundii did not potentiate virulence in either mode. Transtracheal challenge of the lungs of hamster with P. gingivalis initiated an early pneumonitis and later sequelae of necrosis and abscess formation. Also, abscess was induced by direct inoculation of P. gingivalis in the muscles, liver and testes, but did not induce intra-abdominal abscesses. In conclusion, the HAM applied with the SSA procedure caused a localized P. gingivalis tissue infection with practical advantages for quantitative and qualitative studies of P. gingivalis infections. This study also demonstrates the pathogenic potential of P. gingivalis by reproducing similar infections in multiple anatomical sites.

  12. Avian Influenza

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This is a letter from a professor at Clemson University about waterfowl that had been tested for avian influenza at Santee National Wildlife Refuge

  13. Weak negative associations between avian influenza virus infection and movement behaviour in a key host species, the mallard Anas platyrhynchos

    NARCIS (Netherlands)

    J.G.B. Dijk (Jacintha); E. Kleyheeg (Erik); M.B. Soons (Merel B.); B.A. Nolet (Bart); R.A.M. Fouchier (Ron); M. Klaassen (Marcel)

    2015-01-01

    textabstractAnimal movements may contribute to the spread of pathogens. In the case of avian influenza virus, [migratory] birds have been suggested to play a role in the spread of some highly pathogenic strains (e.g. H5N1, H5N8), as well as their low pathogenic precursors which circulate naturally

  14. Mild Respiratory Illness Among Young Children Caused by Highly Pathogenic Avian Influenza A (H5N1) Virus Infection in Dhaka, Bangladesh, 2011.

    Science.gov (United States)

    Chakraborty, Apurba; Rahman, Mahmudur; Hossain, M Jahangir; Khan, Salah Uddin; Haider, M Sabbir; Sultana, Rebeca; Ali Rimi, Nadia; Islam, M Saiful; Haider, Najmul; Islam, Ausraful; Sultana Shanta, Ireen; Sultana, Tahmina; Al Mamun, Abdullah; Homaira, Nusrat; Goswami, Doli; Nahar, Kamrun; Alamgir, A S M; Rahman, Mustafizur; Mahbuba Jamil, Khondokar; Azziz-Baumgartner, Eduardo; Simpson, Natosha; Shu, Bo; Lindstrom, Stephen; Gerloff, Nancy; Davis, C Todd; Katz, Jaqueline M; Mikolon, Andrea; Uyeki, Timothy M; Luby, Stephen P; Sturm-Ramirez, Katharine

    2017-09-15

    In March 2011, a multidisciplinary team investigated 2 human cases of highly pathogenic avian influenza A(H5N1) virus infection, detected through population-based active surveillance for influenza in Bangladesh, to assess transmission and contain further spread. We collected clinical and exposure history of the case patients and monitored persons coming within 1 m of a case patient during their infectious period. Nasopharyngeal wash specimens from case patients and contacts were tested with real-time reverse-transcription polymerase chain reaction, and virus culture and isolates were characterized. Serum samples were tested with microneutralization and hemagglutination inhibition assays. We tested poultry, wild bird, and environmental samples from case patient households and surrounding areas for influenza viruses. Two previously healthy case patients, aged 13 and 31 months, had influenzalike illness and fully recovered. They had contact with poultry 7 and 10 days before illness onset, respectively. None of their 57 contacts were subsequently ill. Clade 2.2.2.1 highly pathogenic avian influenza H5N1 viruses were isolated from the case patients and from chicken fecal samples collected at the live bird markets near the patients' dwellings. Identification of H5N1 cases through population-based surveillance suggests possible additional undetected cases throughout Bangladesh and highlights the importance of surveillance for mild respiratory illness among populations frequently exposed to infected poultry.

  15. Identification of differentially expressed miRNAs in chicken lung and trachea with avian influenza virus infection by a deep sequencing approach

    Directory of Open Access Journals (Sweden)

    Chen Rui

    2009-11-01

    Full Text Available Abstract Background MicroRNAs (miRNAs play critical roles in a wide spectrum of biological processes and have been shown to be important effectors in the intricate host-pathogen interaction networks. Avian influenza virus (AIV not only causes significant economic losses in poultry production, but also is of great concern to human health. The objective of this study was to identify miRNAs associated with AIV infections in chickens. Results Total RNAs were isolated from lung and trachea of low pathogenic H5N3 infected and non-infected SPF chickens at 4 days post-infection. A total of 278,398 and 340,726 reads were obtained from lung and trachea, respectively. And 377 miRNAs were detected in lungs and 149 in tracheae from a total of 474 distinct chicken miRNAs available at the miRBase, respectively. Seventy-three and thirty-six miRNAs were differentially expressed between infected and non-infected chickens in lungs and tracheae, respectively. There were more miRNAs highly expressed in non-infected tissues than in infected tissues. Interestingly, some of these differentially expressed miRNAs, including miR-146, have been previously reported to be associated with immune-related signal pathways in mammals. Conclusion To our knowledge, this is the first study on miRNA gene expression in AIV infected chickens using a deep sequencing approach. During AIV infection, many host miRNAs were differentially regulated, supporting the hypothesis that certain miRNAs might be essential in the host-pathogen interactions. Elucidation of the mechanism of these miRNAs on the regulation of host-AIV interaction will lead to the development of new control strategies to prevent or treat AIV infections in poultry.

  16. Clinical and pathologic responses of American crows (Corvus brachyrhynchos) and fish crows (C ossifragus) to experimental West Nile virus infection.

    Science.gov (United States)

    Nemeth, N M; Thomsen, B V; Spraker, T R; Benson, J M; Bosco-Lauth, A M; Oesterle, P T; Bright, J M; Muth, J P; Campbell, T W; Gidlewski, T L; Bowen, R A

    2011-11-01

    West Nile virus (WNV)-associated disease has a range of clinical manifestations among avian taxa, the reasons for which are not known. Species susceptibility varies within the avian family Corvidae, with estimated mortality rates ranging from 50 to 100%. We examined and compared virologic, immunologic, pathologic, and clinical responses in 2 corvid species, the American crow (Corvus brachyrhynchos) and the fish crow (C ossifragus), following experimental WNV inoculation. Unlike fish crows, which remained clinically normal throughout the study, American crows succumbed to WNV infection subsequent to dehydration, electrolyte and pH imbalances, and delayed or depressed humoral immune responses concurrent with marked, widespread virus replication. Viral titers were approximately 3,000 times greater in blood and 30,000 to 50,000 times greater in other tissues (eg, pancreas and small intestine) in American crows versus fish crows. Histologic lesion patterns and antigen deposition supported the differing clinical outcomes, with greater severity and distribution of lesions and WNV antigen in American crows. Both crow species had multiorgan necrosis and inflammation, although lesions were more frequent, severe, and widespread in American crows, in which the most commonly affected tissues were small intestine, spleen, and liver. American crows also had inflammation of vessels and nerves in multiple tissues, including heart, kidney, and the gastrointestinal tract. WNV antigen was most commonly observed within monocytes, macrophages, and other cells of the reticuloendothelial system of affected tissues. Collectively, the data support that WNV-infected American crows experience uncontrolled systemic infection leading to multiorgan failure and rapid death.

  17. Experimental Babesia gibsoni infection in coyotes (Canis latrans).

    Science.gov (United States)

    Evers, Holly V; Kocan, A Alan; Reichard, Mason V; Meinkoth, James H

    2003-10-01

    Four 5 mo old captive raised coyotes (Canis latrans) were experimentally inoculated with approximately 1 x 10(6) Babesia gibsoni organisms. Parasites were detected 1 wk post-inoculation in all coyotes with maximum parasitemia of 8-11% occurring at 34 wk. Parasitemias remained at or above 1% for at least 12 wk and were still detectable 20 wk post-inoculation. All experimentally infected coyotes developed pale mucous membranes, splenomegaly, and a positive heme reaction in urine while one coyote exhibited mild depression and inappetence. Infected coyotes also developed a regenerative anemia, thrombocytopenia, and neutropenia. The mild clinical signs coupled with the high level and long duration of parasitemia indicate that coyotes could serve as reservoirs for B. gibsoni. Entrance of this foreign parasite into the United States suggests the need for strict quarantines and thorough health and blood film examinations for imported animals.

  18. The avian-origin H3N2 canine influenza virus has limited replication in swine

    Science.gov (United States)

    A genetically and antigenically distinct H3N2 canine influenza of avian-origin was detected in March of 2015 in Chicago, Illinois. A subsequent outbreak was reported with over 1,000 dogs in the Midwest affected. The potential for canine-to-swine transmission was unknown. Experimental infection in pi...

  19. RT-PCR-ELISA as a tool for diagnosis of low-pathogenicity avian influenza

    DEFF Research Database (Denmark)

    Dybkær, Karen; Munch, Mette; Handberg, Kurt

    2003-01-01

    A one-tube reverse transcriptase/polymerase chain reaction coupled with an enzyme-linked immunosorbent assay (RT-PCR-ELISA) was developed for the rapid detection of avian influenza virus (AIV) in clinical specimens. A total of 419 swab pools were analyzed from chickens experimentally infected...

  20. Gastritis induced by Helicobacter pylori infection in experimental rats.

    Science.gov (United States)

    Elseweidy, Mohamed M; Taha, Mona M; Younis, Nahla N; Ibrahim, Khadiga S; Hamouda, Hamdi A; Eldosouky, Mohamed A; Soliman, Hala

    2010-10-01

    Gastritis, an inflammation of gastric mucosa, may be due to many pathological factors and infection, such as with Helicobacter pylori. The use of experimental models of gastritis is important to evaluate the biochemical changes and study chemotherapeutic intervention. In a previous study we demonstrated an acute gastritis model induced by iodoacetamide. Our objective in this study was to evaluate a new gastritis model induced by H. pylori infection in experimental rats in terms of certain biomarkers in serum and mucosal tissues in addition to histopathological examination. Gastritis was induced in 20 albino Wistar rats by H. pylori isolated from antral biopsy taken from a 49-year-old male patient endoscopically diagnosed as having H. pylori infection. Another ten rats were used as controls. Serum gastrin, pepsinogen I activity, interleukin-6 (IL-6) and gastric mucosal myeloperoxidase (MPO) activity and prostaglandin E(2) (PGE(2)) were measured. Immunostaining for inducible nitric oxide synthase (iNOS), nitrotyrosine and DNA fragmentation were used to further evaluate H. pylori-induced gastritis. Serum gastrin, IL-6, mucosal MPO activity, and PGE(2) demonstrated significant increases joined with a decreased serum pepsinogen I activity (P gastritis models demonstrated massive oxidative stress and pronounced injury in mucosal tissue. Since our model in rats reflected the clinical picture of H. pylori infection, it can be considered as a consistent model to study chemotherapeutic intervention for this type of gastritis.

  1. Mono- and combined antimicrobial agents efficiency in experimental wound infection

    Directory of Open Access Journals (Sweden)

    Наталія Ігорівна Філімонова

    2015-10-01

    Full Text Available Modern problems of antibiotic therapy are shown by wide range of side effects, both on organism and microbiological levels: the spread of allergies, toxic for organ systems reactions, dysbiosis development, and resistant pathogens formation and dissemination. Therefore the necessity of search for new effective drugs with significant antimicrobial activity applied for the wounds treatment arises. Development of combined remedies on the background of different origin antimicrobial agents’ derivatives is one of the fight directions against infectious diseases in the skin pathology. Recently among the existing antimicrobial agents one should focus on antiseptic drugs, due to degenerative and dysfunctional effect on microbial cell.Aim of research. The comparison of mono- and combined antimicrobial agents chemotherapeutic efficiency in the treatment of localized purulent infection under experimental conditions.Metods. The study of chemotherapeutic efficiency was carried out on the model of localized purulent Staphylococcus infection on albino mice weighting 14 – 16 g. S.aureus ATCC 25923 strains were used as infectious agents. The contamination was performed subcutaneously to the right side of mice’s skin after depilation. The animals were randomly divided into 4 groups: the 1st group – infected mice without treatment (control; the 2nd group – infected mice treated with a ciprofloxacin; the 3rd group – infected mice treated with a Ciprofloxacin and Decamethoxin combination; the 4th group – infected mice treated with a combined drug on the base of mutual prodrugs (Hexamethylenetetramine and Phenyl salicylate.Results. The efficiency of mono- and combined antimicrobial agents under experimental Staphylococcus wound infection conditions was studied. It was found that localized purulent staph center was formed more slowly in comparison with control and mono preparation use (2nd group of animals. The average index of skin lesions in comparison

  2. Avian pathogenic Escherichia coli (APEC).

    Science.gov (United States)

    Dho-Moulin, M; Fairbrother, J M

    1999-01-01

    Avian pathogenic Escherichia coli (APEC) cause aerosacculitis, polyserositis, septicemia and other mainly extraintestinal diseases in chickens, turkeys and other avian species. APEC are found in the intestinal microflora of healthy birds and most of the diseases associated with them are secondary to environmental and host predisposing factors. APEC isolates commonly belong to certain serogroups, O1, O2 and O78, and to a restricted number of clones. Several experimental models have been developed, permitting a more reliable evaluation of the pathogenicity of E. coli for chickens and turkeys. Hence, virulence factors identified on APEC are adhesins such as the F1 and P fimbriae, and curli, the aerobactin iron sequestering system, K1 capsule, temperature-sensitive hemagglutinin (Tsh), resistance to the bactericidal effects of serum and cytotoxic effects. Experimental infection studies have shown that the air-exchange regions of the lung and the airsacs are important sites of entry of E. coli into the bloodstream of birds during the initial stages of infection and that resistance to phagocytosis may be an important mechanism in the development of the disease. They have also demonstrated that F1 fimbriae are expressed in the respiratory tract, whereas P fimbriae are expressed in the internal organs of infected chickens. The role of these fimbrial adhesins in the development of disease is not yet, however, fully understood. The more recent use of genetic approaches for the identification of new virulence factors will greatly enhance our knowledge of APEC pathogenic mechanisms. Diagnosis of APEC infections is based on the clinical picture, lesions and isolation of E. coli. This may be strengthened by serotyping and identification of virulence factors using immunological or molecular methods such as DNA probes and PCR. Approaches for the prevention and control of APEC infections include the control of environmental contamination and environmental parameters such as

  3. 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.

  4. Up-regulation of Mcl-1 and Bak by coronavirus infection of human, avian and animal cells modulates apoptosis and viral replication.

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    Yanxin Zhong

    Full Text Available Virus-induced apoptosis and viral mechanisms that regulate this cell death program are key issues in understanding virus-host interactions and viral pathogenesis. Like many other human and animal viruses, coronavirus infection of mammalian cells induces apoptosis. In this study, the global gene expression profiles are first determined in IBV-infected Vero cells at 24 hours post-infection by Affymetrix array, using avian coronavirus infectious bronchitis virus (IBV as a model system. It reveals an up-regulation at the transcriptional level of both pro-apoptotic Bak and pro-survival myeloid cell leukemia-1 (Mcl-1. These results were further confirmed both in vivo and in vitro, in IBV-infected embryonated chicken eggs, chicken fibroblast cells and mammalian cells at transcriptional and translational levels, respectively. Interestingly, the onset of apoptosis occurred earlier in IBV-infected mammalian cells silenced with short interfering RNA targeting Mcl-1 (siMcl-1, and was delayed in cells silenced with siBak. IBV progeny production and release were increased in infected Mcl-1 knockdown cells compared to similarly infected control cells, while the contrary was observed in infected Bak knockdown cells. Furthermore, IBV infection-induced up-regulation of GADD153 regulated the expression of Mcl-1. Inhibition of the mitogen-activated protein/extracellular signal-regulated kinase (MEK/ERK and phosphoinositide 3-kinase (PI3K/Akt signaling pathways by chemical inhibitors and knockdown of GADD153 by siRNA demonstrated the involvement of ER-stress response in regulation of IBV-induced Mcl-1 expression. These results illustrate the sophisticated regulatory strategies evolved by a coronavirus to modulate both virus-induced apoptosis and viral replication during its replication cycle.

  5. Up-regulation of Mcl-1 and Bak by coronavirus infection of human, avian and animal cells modulates apoptosis and viral replication.

    Science.gov (United States)

    Zhong, Yanxin; Liao, Ying; Fang, Shouguo; Tam, James P; Liu, Ding Xiang

    2012-01-01

    Virus-induced apoptosis and viral mechanisms that regulate this cell death program are key issues in understanding virus-host interactions and viral pathogenesis. Like many other human and animal viruses, coronavirus infection of mammalian cells induces apoptosis. In this study, the global gene expression profiles are first determined in IBV-infected Vero cells at 24 hours post-infection by Affymetrix array, using avian coronavirus infectious bronchitis virus (IBV) as a model system. It reveals an up-regulation at the transcriptional level of both pro-apoptotic Bak and pro-survival myeloid cell leukemia-1 (Mcl-1). These results were further confirmed both in vivo and in vitro, in IBV-infected embryonated chicken eggs, chicken fibroblast cells and mammalian cells at transcriptional and translational levels, respectively. Interestingly, the onset of apoptosis occurred earlier in IBV-infected mammalian cells silenced with short interfering RNA targeting Mcl-1 (siMcl-1), and was delayed in cells silenced with siBak. IBV progeny production and release were increased in infected Mcl-1 knockdown cells compared to similarly infected control cells, while the contrary was observed in infected Bak knockdown cells. Furthermore, IBV infection-induced up-regulation of GADD153 regulated the expression of Mcl-1. Inhibition of the mitogen-activated protein/extracellular signal-regulated kinase (MEK/ERK) and phosphoinositide 3-kinase (PI3K/Akt) signaling pathways by chemical inhibitors and knockdown of GADD153 by siRNA demonstrated the involvement of ER-stress response in regulation of IBV-induced Mcl-1 expression. These results illustrate the sophisticated regulatory strategies evolved by a coronavirus to modulate both virus-induced apoptosis and viral replication during its replication cycle.

  6. Multivalent HA DNA vaccination protects against highly pathogenic H5N1 avian influenza infection in chickens and mice.

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    Srinivas Rao

    Full Text Available Sustained outbreaks of highly pathogenic avian influenza (HPAI H5N1 in avian species increase the risk of reassortment and adaptation to humans. The ability to contain its spread in chickens would reduce this threat and help maintain the capacity for egg-based vaccine production. While vaccines offer the potential to control avian disease, a major concern of current vaccines is their potency and inability to protect against evolving avian influenza viruses.The ability of DNA vaccines encoding hemagglutinin (HA proteins from different HPAI H5N1 serotypes was evaluated for its ability to elicit neutralizing antibodies and to protect against homologous and heterologous HPAI H5N1 strain challenge in mice and chickens after DNA immunization by needle and syringe or with a pressure injection device. These vaccines elicited antibodies that neutralized multiple strains of HPAI H5N1 when given in combinations containing up to 10 HAs. The response was dose-dependent, and breadth was determined by the choice of the influenza virus HA in the vaccine. Monovalent and trivalent HA vaccines were tested first in mice and conferred protection against lethal H5N1 A/Vietnam/1203/2004 challenge 68 weeks after vaccination. In chickens, protection was observed against heterologous strains of HPAI H5N1 after vaccination with a trivalent H5 serotype DNA vaccine with doses as low as 5 microg DNA given twice either by intramuscular needle injection or with a needle-free device.DNA vaccines offer a generic approach to influenza virus immunization applicable to multiple animal species. In addition, the ability to substitute plasmids encoding different strains enables rapid adaptation of the vaccine to newly evolving field isolates.

  7. The irp2 and fyuA genes in High Pathogenicity Islands are involved in the pathogenesis of infections caused by avian pathogenic Escherichia coli (APEC).

    Science.gov (United States)

    Tu, Jian; Xue, Ting; Qi, Kezong; Shao, Ying; Huang, Boyan; Wang, Xueyan; Zhou, Xiuhong

    2016-01-01

    Avian pathogenic Escherichia coli (APEC) is a major bacterial infectious disease that may lead to local or systemic infections in chickens with clinical manifestations. The irp2-fyuA gene cluster has been confirmed to be the main genes involved in the synthesis of HPI. The objective of this study was to determine the influence of the irp2 and fyuA genes in the high pathogenicity island (HPI) of avian pathogenic Escherichia coli (APEC) on its pathogenicity by knocking out these genes. The ΔAE17 (lacking irp2) and ΔΔAE17 (lacking irp2 and fyuA) strains of APEC were constructed. The ΔAE17 and ΔΔAE17 strains showed significantly impaired capacity to adhere onto DF-1 cells. The LD50 results indicated that the virulence of the ΔAE17 and ΔΔAE17 strains was decreased in comparison with that of the AE17 strain. We concluded that the knock-out of the core HPI genes weakened APEC adhesion onto DF-1 cells, inhibited transcription of virulence genes, and reduced pathogenicity in chicks. The effects of genetic deletion of irp2 and fyuA on APEC were more severe than those produced by deletion of irp2 only, indicating that irp2 and fyuA co-regulate APEC pathogenicity.

  8. Prior infection of chickens with H1N1 or H1N2 avian influenza elicits partial heterologous protection against highly pathogenic H5N1.

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    Charles Nfon

    Full Text Available There is a critical need to have vaccines that can protect against emerging pandemic influenza viruses. Commonly used influenza vaccines are killed whole virus that protect against homologous and not heterologous virus. Using chickens we have explored the possibility of using live low pathogenic avian influenza (LPAI A/goose/AB/223/2005 H1N1 or A/WBS/MB/325/2006 H1N2 to induce immunity against heterologous highly pathogenic avian influenza (HPAI A/chicken/Vietnam/14/2005 H5N1. H1N1 and H1N2 replicated in chickens but did not cause clinical disease. Following infection, chickens developed nucleoprotein and H1 specific antibodies, and reduced H5N1 plaque size in vitro in the absence of H5 neutralizing antibodies at 21 days post infection (DPI. In addition, heterologous cell mediated immunity (CMI was demonstrated by antigen-specific proliferation and IFN-γ secretion in PBMCs re-stimulated with H5N1 antigen. Following H5N1 challenge of both pre-infected and naïve controls chickens housed together, all naïve chickens developed acute disease and died while H1N1 or H1N2 pre-infected chickens had reduced clinical disease and 70-80% survived. H1N1 or H1N2 pre-infected chickens were also challenged with H5N1 and naïve chickens placed in the same room one day later. All pre-infected birds were protected from H5N1 challenge but shed infectious virus to naïve contact chickens. However, disease onset, severity and mortality was reduced and delayed in the naïve contacts compared to directly inoculated naïve controls. These results indicate that prior infection with LPAI virus can generate heterologous protection against HPAI H5N1 in the absence of specific H5 antibody.

  9. Effects of praziquantel on experimental Schistosoma bovis infection in goats.

    Science.gov (United States)

    Johansen, M V; Monrad, J; Christensen, N O

    1996-03-01

    The effect of praziquantel against experimental Schistosoma bovis infection in West African Dwarf goats was investigated. Thirty goats were exposed to 2000 cercariae each and 15 of those received a praziquantel treatment (60 mg kg-1) 13 weeks post-infection. One day, 1 week and 4 weeks post-treatment representative goats from each group were killed and worms were recovered by perfusion. For comparison, parasite-free control animals were monitored, some of which were given praziquantel. Every second week during the study, faecal samples were collected. The cure rate was 100% 1 day, 99.4% 1 week and 95.7% 4 weeks post-treatment. Tissue egg counts were significantly reduced (P < 0.001) 4 weeks post-treatment in all parts of the intestines, but not in the liver. Faecal egg counts were reduced by 84.1% 1 week and by 98.3% 3 weeks after treatment, the reduction being highly significant both 1 week 3 weeks after treatment (P < 0.001). Overall strong correlations between the number of worm pairs, tissue egg counts and the final faecal egg count were observed, indicating that the faecal egg counts during infection and following treatment can be used as a guideline for the pathology associated with the infection.

  10. Circulating levels of cyclooxygenase metabolites in experimental Trypanosoma cruzi infections

    Directory of Open Access Journals (Sweden)

    Rita L. Cardoni

    2004-01-01

    Full Text Available TRYPANOSOMA cruzi induces inflammatory reactions in several tissues. The production of prostaglandin F2α, 6-keto-prostaglandin F1α and thromboxane B2, known to regulate the immune response and to participate in inflammatory reactions, was studied in mice experimentally infected with T. cruzi. The generation of nitric oxide (NO, which could be regulated by cyclooxygenase metabolites, was also evaluated. In the acute infection the extension of inflammatory infiltrates in skeletal muscle as well as the circulating levels of cyclooxygenase metabolites and NO were higher in resistant C3H mice than in susceptible BALB/c mice. In addition, the spontaneous release of NO by spleen cells increased earlier in the C3H mouse strain. In the chronic infections, the tissue inflammatory reaction was still prominent in both groups of mice, but a moderate increase of thromboxane B2 concentration and in NO released by spleen cells was observed only in C3H mice. This comparative study shows that these mediators could be mainly related to protective mechanisms in the acute phase, but seem not to be involved in its maintenance in the chronic T. cruzi infections.

  11. Avian Flu Epidemic 2003: Public health consequences. Executive summary

    NARCIS (Netherlands)

    Bosman A; Mulder YM; Leeuw JRJ de; Meijer A; Du Ry van Beest Holle M; Kamst RA; Velden PG van der; Conyn-van Spaendonck MAE; Koopmans MPG; Ruijten MWMM; Instituut voor Psychotrauma; CIE; MGO; LIS

    2004-01-01

    Executive summary Avian flu epidemic 2003: public health consequences.Risk factors, health, well-being, health care needs and preventive measures during the H7N7 avian flu outbreak control in the Netherlands.An estimated thousand people, possibly more have been infected with avian flu during the

  12. Experimental rhinovirus infection in human volunteers exposed to ozone

    Energy Technology Data Exchange (ETDEWEB)

    Henderson, F.W.; Dubovi, E.J.; Harder, S.; Seal, E. Jr.; Graham, D.

    1988-05-01

    We studied 24 young adult male volunteers experimentally inoculated with type 39 rhinovirus to determine whether the course of viral infection was modified by exposure to moderate levels of ozone (0.3 ppm for 6 h per day) over the 5 days after virus inoculation. No differences in rhinovirus titers in nasal secretions, recruitment of neutrophils into nasal secretions, levels of interferon in nasal lavage fluid, in vitro lymphocyte proliferative responses to rhinovirus antigen, or levels of convalescent serum neutralizing antibody to type 39 rhinovirus were demonstrated in relation to ozone exposure. The level and pattern of ozone exposure used in this experiment had no demonstrable adverse effects on the immune responses necessary to limit and terminate rhinovirus infection of the upper respiratory tract.

  13. Experimental rhinovirus infection in human volunteers exposed to ozone.

    Science.gov (United States)

    Henderson, F W; Dubovi, E J; Harder, S; Seal, E; Graham, D

    1988-05-01

    We studied 24 young adult male volunteers experimentally inoculated with type 39 rhinovirus to determine whether the course of viral infection was modified by exposure to moderate levels of ozone (0.3 ppm for 6 h per day) over the 5 days after virus inoculation. No differences in rhinovirus titers in nasal secretions, recruitment of neutrophils into nasal secretions, levels of interferon in nasal lavage fluid, in vitro lymphocyte proliferative responses to rhinovirus antigen, or levels of convalescent serum neutralizing antibody to type 39 rhinovirus were demonstrated in relation to ozone exposure. The level and pattern of ozone exposure used in this experiment had no demonstrable adverse effects on the immune responses necessary to limit and terminate rhinovirus infection of the upper respiratory tract.

  14. Highly pathogenic or low pathogenic avian influenza virus subtype H7N1 infection in chicken lungs: small differences in general acute responses.

    NARCIS (Netherlands)

    Rebel, J.M.J.; Peeters, B.P.H.; Fijten, H.P.D.; Post, J.; Cornelissen, J.B.W.J.; Vervelde, L.

    2011-01-01

    Avian influenza virus can be divided into two groups, highly pathogenic avian influenza virus (HPAI) and low pathogenic avian influenza virus (LPAI) based on their difference in virulence. To investigate if the difference in clinical outcome between LPAI and HPAI in chickens is due to immunological

  15. Vaccine-induced protection from egg production losses in commercial turkey breeder hens following experimental challenge with a triple-reassortant H3N2 avian influenza virus.

    Science.gov (United States)

    Kapczynski, Darrell R; Gonder, Eric; Liljebjelke, Karen; Lippert, Ron; Petkov, Daniel; Tilley, Becky

    2009-03-01

    Infections of avian influenza virus (AIV) in turkey breeder hens can cause a decrease in both egg production and quality, resulting in significant production losses. In North Carolina in 2003, a triple-reassortant H3N2 AIV containing human, swine, and avian gene segments was isolated from turkey breeder hens (A/turkey/NC/16108/03). This viral subtype was subsequently isolated from both turkeys and swine in Ohio in 2004, and in Minnesota in 2005, and was responsible for significant losses in turkey production. The objective of this study was to determine if currently available commercial, inactivated avian influenza H3 subtype oil-emulsion vaccines would protect laying turkey hens from egg production losses following challenge with the 2003 H3N2 field virus isolate from North Carolina. Laying turkey hens were vaccinated in the field with two injections of either a commercial monovalent (A/duck/Minnesota/79/79 [H3N4]) or autogenous bivalent (A/turkey/North Carolina/05 (H3N2)-A/turkey/North Carolina/88 [H1N1]) vaccine, at 26 and 30 wk of age, and subsequently challenged under BSL 3-Ag conditions at 32 wk of age. Vaccine-induced efficacy was determined as protection from a 50% decrease in egg production and from a decrease in egg quality within 21 days postchallenge. Results indicate that, following a natural route of challenge (eye drop and intranasal), birds vaccinated with the 2005 North Carolina H3N2 subtype were significantly protected from the drop in egg production observed in both the H3N4 vaccinated and sham-vaccinated hens. The results demonstrate that groups receiving vaccines containing either H3 subtype had a decreased number of unsettable eggs, increased hemagglutination inhibition titers following challenge, and decreased virus isolations from cloacal swabs as compared to the sham-vaccinated group. Phylogenetic analysis of the nucleotide sequence of the HA1 gene segment from the three H3 viruses used in these studies indicated that the two North Carolina

  16. Protective efficacy of passive immunization with monoclonal antibodies in animal models of H5N1 highly pathogenic avian influenza virus infection.

    Directory of Open Access Journals (Sweden)

    Yasushi Itoh

    2014-06-01

    Full Text Available Highly pathogenic avian influenza (HPAI viruses of the H5N1 subtype often cause severe pneumonia and multiple organ failure in humans, with reported case fatality rates of more than 60%. To develop a clinical antibody therapy, we generated a human-mouse chimeric monoclonal antibody (MAb ch61 that showed strong neutralizing activity against H5N1 HPAI viruses isolated from humans and evaluated its protective potential in mouse and nonhuman primate models of H5N1 HPAI virus infections. Passive immunization with MAb ch61 one day before or after challenge with a lethal dose of the virus completely protected mice, and partial protection was achieved when mice were treated 3 days after the challenge. In a cynomolgus macaque model, reduced viral loads and partial protection against lethal infection were observed in macaques treated with MAb ch61 intravenously one and three days after challenge. Protective effects were also noted in macaques under immunosuppression. Though mutant viruses escaping from neutralization by MAb ch61 were recovered from macaques treated with this MAb alone, combined treatment with MAb ch61 and peramivir reduced the emergence of escape mutants. Our results indicate that antibody therapy might be beneficial in reducing viral loads and delaying disease progression during H5N1 HPAI virus infection in clinical cases and combined treatment with other antiviral compounds should improve the protective effects of antibody therapy against H5N1 HPAI virus infection.

  17. Discrepancy in the diagnosis of avian Borna disease virus infection of Psittaciformes by protein analysis of feather calami and enzyme-linked immunosorbent assay of plasma antibodies.

    Science.gov (United States)

    McHugh, Josephine M; de Kloet, Siwo R

    2015-03-01

    The present study compares diagnosis of avian Borna disease virus (ABV) infection of psittacine birds by Western blot of bornaviral proteins in dried feather stems with the detection of anti-bornaviral protein antibodies to bornaviral proteins in plasma by enzyme-linked immunosorbent assay (ELISA). The detection of ABV proteins P40 and P24 in feather calami by Western blotting was possible even after storage of the dried feathers for several years at ambient temperature. Serological identification of anti-bornaviral antibodies may fail (e.g., in young birds, hatched from infected parents), whereas bornaviral P40 and P24 proteins were detected in feather stems. This failure can last at least 10 months after the birds are hatched. In some older birds (>5 years), ABV protein was only detectable in the brain, but not in some peripheral tissues, suggesting that the immune system had succeeded in removing the infecting ABV from tissues outside the brain. These results show that a combination of feather stem analysis for the presence of bornaviral proteins by Western blot combined with serological detection of anti-bornaviral antibodies by ELISA is the most reliable procedure for the detection of a bornaviral infection. © 2015 The Author(s).

  18. Isolation of a novel thermophilic Campylobacter from cases of spotty liver disease in laying hens and experimental reproduction of infection and microscopic pathology.

    Science.gov (United States)

    Crawshaw, Tim R; Chanter, Jeremy I; Young, Stuart C L; Cawthraw, Shaun; Whatmore, Adrian M; Koylass, Mark S; Vidal, Ana B; Salguero, Francisco J; Irvine, Richard M

    2015-09-30

    The condition known as spotty liver disease or spotty liver syndrome can cause significant mortality in free range laying hen flocks. It has been described in Europe and Australia but the aetiology has not been established. There are similarities between spotty liver disease and avian vibrionic hepatitis, a condition which was reported in the 1950s. A Vibrio-like organism was suspected to be the cause of avian vibrionic hepatitis, although this organism was never fully characterised. We report the isolation of a novel Campylobacter from five separate outbreaks of spotty liver disease. The conditions required for culture, the growth characteristics, electron microscopical morphology and results of the phenotypic tests used in the identification of this novel Campylobacter sp. are described. The novel Campylobacter is slow growing and fastidious and does not grow on media routinely used for isolating Campylobacter sp. The morphology is typical for a Campylobacter sp. and phenotypic tests and a duplex real time PCR test differentiate the novel Campylobacter from other members of the genus. 16S rRNA analysis of 19 isolates showed an identical sequence which appears to represent a hitherto unknown sub lineage within the genus Campylobacter. Experimental intraperitoneal infection of four week old SPF chickens produced microscopic liver pathology indistinguishable from natural disease and the novel Campylobacter was recovered from the experimentally infected chicks. The isolates described appear to be a possible causal organism for spotty liver disease. Crown Copyright © 2015. Published by Elsevier B.V. All rights reserved.

  19. Histopathological changes in sheep experimentally infected with Babesia ovis.

    Science.gov (United States)

    Habela, M A; Reina, D; Navarrete, I; Redondo, E; Hernández, S

    1991-01-01

    Histopathological study was made of 12 Merino sheep - five splenectomized and seven intact - experimentally infected with Babesia ovis. Non-purulent encephalitis; initially exudative and subsequently interstitial pneumonia; pericarditis, myocarditis and haemorrhagic endocarditis; centrilobular necrotic hepatitis; hyperplasia of the lymphoreticular system; necrosis and vascular changes in adrenal glands were observed. The kidney was the most severely affected organ, exhibiting acute tubular necrosis typical of kidney shock syndrome. The lesions observed were suggestive of hypovolemic shock culminating in haemorrhagic diathesis owing to consumptive coagulopathy. Additionally, the massive release of catabolites from lysis and necrosis apparently produced endotoxic shock.

  20. Karyotype analysis of the acute fibrosarcoma from chickens infected with subgroup J avian leukosis virus associated with v-src oncogene.

    Science.gov (United States)

    Dong, Xuan; Ju, Sidi; Chen, Junxia; Meng, Fanfeng; Sun, Peng; Li, Yang; Wang, Xin; Wang, Yixin; Liu, Juan; Chang, Shuang; Zhao, Peng; Cui, Zhizhong

    2016-01-01

    To understand the cytogenetic characteristics of acute fibrosarcoma in chickens infected with the subgroup J avian leukosis virus associated with the v-src oncogene, we performed a karyotype analysis of fibrosarcoma cell cultures. Twenty-nine of 50 qualified cell culture spreads demonstrated polyploidy of some macrochromosomes, 21 of which were trisomic for chromosome 7, and others were trisomic for chromosomes 3, 4, 5 (sex chromosome w), and 10. In addition, one of them was trisomic for both chromosome 7 and the sex chromosome 5 (w). In contrast, no aneuploidy was found for 10 macrochromosomes of 12 spreads of normal chicken embryo fibroblast cells, although aneuploidy for some microchromosomes was demonstrated in five of the 12 spreads. The cytogenetic mosaicism or polymorphism of the aneuploidy in the acute fibrosarcoma described in this study suggests that the analysed cells are polyclonal.

  1. Use of a tetanus toxoid marker to allow differentiation of infected from vaccinated poultry without affecting the efficacy of a H5N1 avian influenza virus vaccine.

    Science.gov (United States)

    James-Berry, C M; Middleton, D; Mansfield, J P; Fenwick, S G; Ellis, T M

    2010-10-30

    Tetanus toxoid (TT) was assessed as a positive marker for avian influenza (AI) virus vaccination in chickens, in a vaccination and challenge study. Chickens were vaccinated twice with inactivated AI H5N2 virus vaccine, and then challenged three weeks later with highly pathogenic AI H5N1 virus. Vaccinated chickens were compared with other groups that were either sham-vaccinated or vaccinated with virus with the TT marker. All sham-vaccinated chickens died by 36 hours postinfection, whereas all vaccinated chickens, with or without the TT marker, were protected from morbidity and mortality following exposure to the challenge virus. Serological testing for H5-specific antibodies identified anamnestic responses to H5 in some of the vaccinated birds, indicating active virus infection.

  2. Emergence and establishment of Usutu virus infection in wild and captive avian species in and around Zurich, Switzerland--genomic and pathologic comparison to other central European outbreaks.

    Science.gov (United States)

    Steinmetz, Hanspeter W; Bakonyi, Tamás; Weissenböck, Herbert; Hatt, Jean-Michel; Eulenberger, Ulrike; Robert, Nadia; Hoop, Richard; Nowotny, Norbert

    2011-03-24

    In late summer 2006 considerable mortality in wild and captive Passeriformes and Strigiformes was observed in Zurich, Switzerland. All animals were found in a range of 2 km(2). Observed clinical signs involved depression, ruffled plumage, incoordination, seizures and peracute death. Nutritional status was generally moderate to poor in wild birds, and variable in captive animals. Necropsy showed marked splenomegaly, a mild hepatomegaly, and pulmonary hyperemia in most animals. Histopathologic lesions were very discrete and consisted mainly of neuronal necrosis, leucocytolysis in and around the brain blood vessels, and miliary liver necrosis. The diagnosis Usutu virus (USUV) infection was established by USUV-specific immunohistochemistry and reverse transcription-polymerase chain reaction. Partial nucleotide sequence comparisons revealed>99% identity between the viruses that emerged in Zurich in 2006, in Vienna in 2001, and in Budapest in 2005. Since 2008 a significantly lower mortality was observed in wild Passeriformes, but USUV infection was confirmed for the first time beyond Zurich city limits. Indoor housing and regular treatment against ectoparasites are likely to have prevented acute USUV disease in captive Strigiformes. USUV is a mosquito-borne flavivirus causing fatalities in various avian species. After the initial European outbreaks in Austria in 2001 it appears that the virus has extended its range in Central Europe and has established a transmission cycle between local bird and mosquito species. Further episodes of increased avian mortality in the forthcoming years, with impact on wild and captive bird populations, predominantly Passeriformes and Strigiformes, can be anticipated. Furthermore, the possibility of broader dispersal of USUV in Europe during the next mosquito seasons must be considered and an increased mortality in Passeriformes and Strigiformes must be expected until protective "flock immunity" is established. Collections of valuable and

  3. Activation of type I and III interferon signalling pathways occurs in lung epithelial cells infected with low pathogenic avian influenza viruses.

    Directory of Open Access Journals (Sweden)

    Richard Sutejo

    Full Text Available The host response to the low pathogenic avian influenza (LPAI H5N2, H5N3 and H9N2 viruses were examined in A549, MDCK, and CEF cells using a systems-based approach. The H5N2 and H5N3 viruses replicated efficiently in A549 and MDCK cells, while the H9N2 virus replicated least efficiently in these cell types. However, all LPAI viruses exhibited similar and higher replication efficiencies in CEF cells. A comparison of the host responses of these viruses and the H1N1/WSN virus and low passage pH1N1 clinical isolates was performed in A549 cells. The H9N2 and H5N2 virus subtypes exhibited a robust induction of Type I and Type III interferon (IFN expression, sustained STAT1 activation from between 3 and 6 hpi, which correlated with large increases in IFN-stimulated gene (ISG expression by 10 hpi. In contrast, cells infected with the pH1N1 or H1N1/WSN virus showed only small increases in Type III IFN signalling, low levels of ISG expression, and down-regulated expression of the IFN type I receptor. JNK activation and increased expression of the pro-apoptotic XAF1 protein was observed in A549 cells infected with all viruses except the H1N1/WSN virus, while MAPK p38 activation was only observed in cells infected with the pH1N1 and the H5 virus subtypes. No IFN expression and low ISG expression levels were generally observed in CEF cells infected with either AIV, while increased IFN and ISG expression was observed in response to the H1N1/WSN infection. These data suggest differences in the replication characteristics and antivirus signalling responses both among the different LPAI viruses, and between these viruses and the H1N1 viruses examined. These virus-specific differences in host cell signalling highlight the importance of examining the host response to avian influenza viruses that have not been extensively adapted to mammalian tissue culture.

  4. The Pathology of Experimental Rhoodococcus equi infection in foals

    Directory of Open Access Journals (Sweden)

    Karima Al-Salihi

    2013-03-01

    Full Text Available The pathology of experimental Rhodococcus equi (R. equi infection in 2-8 weeks-old-foal is studied. For this purpose, twenty foals were divided into three groups, and given R. equi intratracheally (1st group, through gastric route (2nd group and through umbilicus by contamination (3rd group. A control group of foals were given a Phosphate buffered Saline (PBS. Pulmonary and intestinal lesions were seen in foals of all infected groups. Grossly, there were multiple, variable-sized abscesses diffusely scattered throughout the lung parenchyma, in addition to the presence of different stages of pneumonia with variable-sized areas of consolidation and emphysema. Intestinal lesions were evident as engorgement of mesenteric blood vessels, subserosal hemorrhages seen along the intestinal tract especially the small intestine, in addition to enlargement of lymph nodes (mesenteric, bronchial and mediastinal. Some lymph nodes were edematous, have circular foci of caseous necrosis and some of them were filled with yellowish, thick creamy pus. The microscopic lesions were basically similar in all foals of the experimental groups, but varied depending on the time of death or euthanasia and included: acute pulmonary congestion, acute suppurative broncho-pneumonia, chronic pyogranulomatous pneumonia, and emphysematous and atelectatic area. There were focal necrosis of the pulmonary parenchyma and numerous bacterial colonies seen free or as aggregates within the cytoplasm of many histiocytes. Also, there were focal interstitial thickening of the alveolar septae. The pleura and interlobular septae were thickened due to cellular infiltration.

  5. Neospora caninum infection in birds: experimental infections in chicken and embryonated eggs.

    Science.gov (United States)

    Furuta, P I; Mineo, T W P; Carrasco, A O T; Godoy, G S; Pinto, A A; Machado, R Z

    2007-12-01

    Neospora caninum causes economical impact in cattle-raising farms since it is implicated as the major cause of bovine abortions. Although infection by the parasite has been widely described in mammals, the role of birds in its life-cycle is still obscure. Therefore, this work aimed to evaluate the infection by N. caninum in different chicken models. Experimental infections were conducted in 7-day-old chicks, laying hens and embryonated eggs, where samples were analysed for parasite burden, IgG antibodies and lesions promoted. Chickens demonstrated an asymptomatic infection, although with seroconversion and systemic replication of the parasite. In laying hens, no signs of vertical transmission were observed. However, embryonated eggs inoculated by the allantoic cavity route demonstrated susceptibility to infection, with mortality rates around 50% independent of the inoculum dose. Additionally, dogs became infected after ingestion of different amounts of inoculated eggs, producing either oocysts or specific IgG antibodies. The results herein presented demonstrate that chickens may be intermediate hosts of N. caninum and that embryonated eggs could be a useful model to study the parasite's biology.

  6. 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

  7. Modulation of the innate immune-related genes expression in H9N2 avian influenza virus-infected chicken macrophage-like cells (HD11) in response to Escherichia coli LPS stimulation.

    Science.gov (United States)

    Qi, Xuefeng; Liu, Caihong; Li, Ruiqiao; Zhang, Huizhu; Xu, Xingang; Wang, Jingyu

    2017-04-01

    Macrophages play important roles in mediating virus-induced innate immune responses and are thought to be involved in the pathogenesis of bacterial superinfections. The innate immune response initiated by both low pathogenicity AIV and bacterial superinfection in their avian host is not fully understood. We therefore determine the transcripts of innate immune-related genes following avian H9N2 AIV virus infection and E. coli LPS co-stimulation of avian macrophage-like cell line HD11 cells. More pronounced expression of pro-inflammatory cytokines (IL-6 and IL-1β) as well as the inflammatory chemokines (CXCLi1 and CXCLi2) was observed in virus infected plus LPS treated HD11 cells compared to H9N2 virus solely infected control. For two superinfection groups, the levels of genes examined in a prior H9N2 virus infection before secondary LPS treatment group were significantly higher as compared with simultaneous virus infection plus LPS stimulation group. Interestingly, similar high levels of IL-6 gene were observed between LPS sole stimulation group and two superinfection groups. Moreover, IL-10 and TGF-β3 mRNA levels in both superinfection groups were moderately upregulated compared to sole LPS stimulation group or virus alone infection group. Although TLR4 and MDA5 levels in virus alone infection group were significantly lower compared to that in both superinfection groups, TLR4 upregulation respond more rapid to virus sole infection compared to LPS plus virus superinfection. Collectively, innate immune-related genes respond more pronounced in LPS stimulation plus H9N2 virus infection HD11 cells compared to sole virus infection or LPS alone stimulation control cells. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. Multimeric recombinant M2e protein-based ELISA: a significant improvement in differentiating avian influenza infected chickens from vaccinated ones.

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    Farshid Hadifar

    Full Text Available Killed avian influenza virus (AIV vaccines have been used to control H5N1 infections in countries where the virus is endemic. Distinguishing vaccinated from naturally infected birds (DIVA in such situations however, has become a major challenge. Recently, we introduced the recombinant ectodomain of the M2 protein (M2e of H5N1 subtype as a novel tool for an ELISA based DIVA test. Despite being antigenic in natural infection the monomer form of the M2e used in ELISA had limited antigenicity and consequently poor diagnostic capability. To address this shortcoming, we evaluated the use of four tandem copies of M2e (tM2e for increased efficiency of M2e antibody detection. The tM2e gene of H5N1 strain from Indonesia (A/Indonesia/CDC540/2006 was cloned into a pMAL- p4x expression vector and expressed in E.coli as a recombinant tM2e-MBP or M2e-MBP proteins. Both of these, M2e and tM2e antigens reacted with sera obtained from chickens following live H5N1 infection but not with sera from vaccinated birds. A significantly stronger M2e antibody reaction was observed with the tM2e compared to M2e antigen. Western blotting also supported the superiority of tM2e over M2e in detection of specific M2e antibodies against live H5N1 infection. Results from this study demonstrate that M2e tetramer is a better antigen than single M2e and could be more suitable for an ELISA based DIVA test.

  9. The effect of infectious bursal disease virus induced immunosuppression on vaccination against highly pathogenic avian influenza virus

    Science.gov (United States)

    Poor efficacy of avian influenza virus (AIV) vaccines in chickens has been documented in the field in spite of good results in experimental settings. Although the causes are multi-factorial and complex, one contributing factor may be prior infection with immunosuppressive viruses. In an effort to ...

  10. An overview on avian influenza

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    Nelson Rodrigo da Silva Martins

    2012-06-01

    Full Text Available Avian influenza (AI is considered an exotic disease in the Brazilian poultry industry, according to the National Avian Health Program (PNSA, with permanent monitoring of domestic, exotic and native avian species. Brazil presents privileged environmental conditions of reduced risk. In addition, all commercial poultry and conservation holdings are registered in state or national inventories and geographically located (GPS for health control. Poultry health standards are adopted for the conformity to the international market, mostly for the intensified poultry destined for exportation, but also for companion exotic and native conservation facilities. Guidelines for monitoring and the diagnosis of AI are published by the PNSA and follow the standards proposed by the international health code (World Organization for Animal Health, Organization International des Epizooties - OIE and insure the free of status for avian influenza virus (AIV of LPAIV-low pathogenicity AIV and HPAIV-high pathogenicity AIV. In addition, the infections by mesogenic and velogenic Newcastle disease virus, Mycoplasma gallisepticum, M. synoviae and M. meleagridis, Salmonella enteric subspecies enterica serovar Gallinarum biovars Gallinarum and Pullorum are eradicated from reproduction. Controlled infections by S.enterica subspecies enterica serovars Enteritidis and Typhimurium are monitored for breeders. The vaccination of chickens in ovo or at hatch against Marek's disease is mandatory. Broiler production is an indoor activity, confinement which insures biosecurity, with safe distances from the potential AIV reservoir avian species. Worldwide HPAIV H5N1 notifications to the OIE, in March 2011, included 51 countries.

  11. Electromagnetic radiation influence on clinical course of experimental wound infection

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    Pronina Е.А.

    2010-09-01

    Full Text Available The article gives close attention to the study of electromagnetic radiation influence (EMR at the frequency of molecular spectrum absorption and radiation (MSAR of nitric oxide (150 GHz and atmospheric oxygen (129 GHz on the clinical course of experimental wound infection caused by antibiotic-sensitive and antibiotic-resistant strains of Pseudomonas aeruginosa. The panoramic spectrometric measuring complex, developed in Saratov Scientific Research Institute of Measuring Equipment was used while carrying out the research. Electromagnetic vibrations of extremely high frequencies were stimulated in this complex imitating the atmospheric oxygen and nitric oxide absorption and radiation molecular spectrum structure. The experiments proved the fact that exposure to radiation at the frequency of molecular spectrum absorption and radiation (MSAR of nitric oxide and atmospheric oxygen had positive impact on the course of traumatic process

  12. A biologically conjugated polysaccharide vaccine delivered by attenuated Salmonella Typhimurium provides protection against challenge of avian pathogenic Escherichia coli O1 infection.

    Science.gov (United States)

    Han, Yue; Liu, Qing; Yi, Jie; Liang, Kang; Wei, Yunan; Kong, Qingke

    2017-11-30

    Avian pathogenic Escherichia coli (APEC) causes avian airsacculitis and colibacillosis, resulting in significant economic loss to the poultry industry. O1, O2 and O78 are the three predominant serotypes. O-antigen of lipopolysaccharide is serotype determinant and highly immunogenic, and O-antigen polysaccharide-based vaccines have great potential for preventing bacterial infections. In this study, we utilized a novel yeast/bacterial shuttle vector pSS26 to clone the 10.8 kb operon synthesizing APEC O1 O-antigen polysaccharide. The resulting plasmid was introduced into attenuated Salmonella vaccines to deliver this O-antigen polysaccharide. O1 O-antigen was stably synthesized in attenuated Salmonella Typhimurium, demonstrated by slide agglutination, silver staining and western blot. Our results also showed that APEC O1 O-antigen produced in the Salmonella vaccines was attached to bacterial cell surfaces, and the presence of heterologous O-antigen did not alter the resistance to surface-acting agents. Furthermore, birds immunized orally or intramuscularly provided protection against the virulent O1 APEC challenge. Salmonella vaccines carrying APEC O1 O-antigen gene cluster also induced high IgG and IgA immune responses against lipopolysaccharide from the APEC O1 strain. The use of our novel shuttle vector facilitates cloning of large DNA fragments, and this strategy could pave the way for production of Salmonella-vectored vaccines against prevalent APEC serotypes. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  13. Assessing cyber-user awareness of an emerging infectious disease: evidence from human infections with avian influenza A H7N9 in Zhejiang, China.

    Science.gov (United States)

    Liu, Biyao; Wang, Zhen; Qi, Xiaohua; Zhang, Xingqin; Chen, Huiping

    2015-11-01

    The aim of this study was to assess cyber-user awareness of human infections with avian influenza A H7N9 in Zhejiang, China. Daily Baidu index values were compared for different keywords, different periods (epidemic and non-epidemic), different levels of epidemic publicity (whether new cases were publicized), and different cities (divided into high, medium, low, and zero groups according to the number of cases). Furthermore, the correlation between the daily Baidu index values and the daily number of new cases was analyzed. Three epidemic periods (periods A/C/E) and three non-epidemic periods (periods B/D/F) were identified from April 2013 to May 2015 according to the curves of daily new cases. Each epidemic period was followed by a non-epidemic period. Baidu index values using 'H7N9' as a keyword were higher than the values using the keyword '' (avian influenza in Chinese) in earlier periods, but the situation reversed in later periods. Index values for 'H7N9' in the epidemic periods were higher than in the non-epidemic periods. In the first epidemic period (period A), the Baidu index values for 'H7N9' showed no difference between the different levels of epidemic publicity and had no correlation with the daily number of new cases. The index values in cities without reported cases showed no difference from the values recorded in the medium and low groups. However, a difference and a correlation were found in a later epidemic period. The Baidu index would be a useful tool for assessing cyber-user awareness of an emerging infectious disease. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  14. Changing Geographic Patterns and Risk Factors for Avian Influenza A(H7N9) Infections in Humans, China.

    Science.gov (United States)

    Artois, Jean; Jiang, Hui; Wang, Xiling; Qin, Ying; Pearcy, Morgan; Lai, Shengjie; Shi, Yujing; Zhang, Juanjuan; Peng, Zhibin; Zheng, Jiandong; He, Yangni; Dhingra, Madhur S; von Dobschuetz, Sophie; Guo, Fusheng; Martin, Vincent; Kalpravidh, Wantanee; Claes, Filip; Robinson, Timothy; Hay, Simon I; Xiao, Xiangming; Feng, Luzhao; Gilbert, Marius; Yu, Hongjie

    2018-01-01

    The fifth epidemic wave of avian influenza A(H7N9) virus in China during 2016-2017 demonstrated a geographic range expansion and caused more human cases than any previous wave. The factors that may explain the recent range expansion and surge in incidence remain unknown. We investigated the effect of anthropogenic, poultry, and wetland variables on all epidemic waves. Poultry predictor variables became much more important in the last 2 epidemic waves than they were previously, supporting the assumption of much wider H7N9 transmission in the chicken reservoir. We show that the future range expansion of H7N9 to northern China may increase the risk of H7N9 epidemic peaks coinciding in time and space with those of seasonal influenza, leading to a higher risk of reassortments than before, although the risk is still low so far.

  15. Mercury Reduces Avian Reproductive Success and Imposes Selection: An Experimental Study with Adult- or Lifetime-Exposure in Zebra Finch

    Science.gov (United States)

    Varian-Ramos, Claire W.; Swaddle, John P.; Cristol, Daniel A.

    2014-01-01

    Mercury is a global pollutant that biomagnifies in food webs, placing wildlife at risk of reduced reproductive fitness and survival. Songbirds are the most diverse branch of the avian evolutionary tree; many are suffering persistent and serious population declines and we know that songbirds are frequently exposed to mercury pollution. Our objective was to determine the effects of environmentally relevant doses of mercury on reproductive success of songbirds exposed throughout their lives or only as adults. The two modes of exposure simulated philopatric species versus dispersive species, and are particularly relevant because of the heightened mercury-sensitivity of developing nervous systems. We performed a dosing study with dietary methylmercury in a model songbird species, the zebra finch (Taeniopygia guttata), at doses from 0.3 – 2.4 parts per million. Birds were exposed to mercury either as adults only or throughout their lives. All doses of mercury reduced reproductive success, with the lowest dose reducing the number of independent offspring produced in one year by 16% and the highest dose, representing approximately half the lethal dose for this species, causing a 50% reduction. While mercury did not affect clutch size or survivorship, it had the most consistent effect on the proportion of chicks that fledged from the nest, regardless of mode of exposure. Among birds exposed as adults, mercury caused a steep increase in the latency to re-nest after loss of a clutch. Birds exposed for their entire lifetimes, which were necessarily the offspring of dosed parents, had up to 50% lower reproductive success than adult-exposed birds at low doses of methylmercury, but increased reproductive success at high doses, suggesting selection for mercury tolerance at the highest level of exposure. Our results indicate that mercury levels in prey items at contaminated sites pose a significant threat to populations of songbirds through reduced reproductive success. PMID

  16. Long-term avian research at the San Joaquin Experimental Range: recommendations for monitoring and managing oak woodlands

    Science.gov (United States)

    Kathryn L. Purcell

    2011-01-01

    Experimental forests and ranges are living laboratories that provide opportunities for conducting scientific research and transferring research results to partners and stakeholders. They are invaluable for their long-term data and capacity to foster collaborative, interdisciplinary research. The San Joaquin Experimental Range (SJER) was established to develop...

  17. Physician's knowledge, attitudes, and practices regarding seasonal influenza, pandemic influenza, and highly pathogenic avian influenza A (H5N1) virus infections of humans in Indonesia.

    Science.gov (United States)

    Mangiri, Amalya; Iuliano, A Danielle; Wahyuningrum, Yunita; Praptiningsih, Catharina Y; Lafond, Kathryn E; Storms, Aaron D; Samaan, Gina; Ariawan, Iwan; Soeharno, Nugroho; Kreslake, Jennifer M; Storey, J Douglas; Uyeki, Timothy M

    2017-01-01

    Indonesia has reported highest number of fatal human cases of highly pathogenic avian influenza (HPAI) A (H5N1) virus infection worldwide since 2005. There are limited data available on seasonal and pandemic influenza in Indonesia. During 2012, we conducted a survey of clinicians in two districts in western Java, Indonesia, to assess knowledge, attitudes, and practices (KAP) of clinical diagnosis, testing, and treatment of patients with seasonal influenza, pandemic influenza, or HPAI H5N1 virus infections. Overall, a very low percentage of physician participants reported ever diagnosing hospitalized patients with seasonal, pandemic, or HPAI H5N1 influenza. Use of influenza testing was low in outpatients and hospitalized patients, and use of antiviral treatment was very low for clinically diagnosed influenza patients. Further research is needed to explore health system barriers for influenza diagnostic testing and availability of antivirals for treatment of influenza in Indonesia. © 2016 The Authors. Influenza and Other Respiratory Viruses Published by John Wiley & Sons Ltd.

  18. Co-infection of Avian Leukosis Virus and Salmonella pullorum with the Preliminary Eradication in Breeders of Chinese Local “ShouGuang” Chickens

    Directory of Open Access Journals (Sweden)

    Jian Qiang Huang, Jing Kai Xin, Cui Mao, Feng Zhong and Jia Qian Chai*

    2013-11-01

    Full Text Available The study was designed to investigate the infection status and to finish the preliminary eradication of avian leukosis virus (ALV and Salmonella pullorum (SP in breeders of Chinese local “ShouGuang” chickens. ALV antigen and antibody was tested via ELISA, and SP antibody was detected by serum plate agglutination test (SPAT. The etiology and pathology was also studied. The ALV-P27 antigen, ALV-A/B and SP antibody positive chickens were eliminated in turn, and then the negative were retained as the breeder flocks. The results showed that the positive rate of antigen to ALV-P27, antibody to ALV-A/B, ALV-J and SP was 57.8, 6.7, 0 and 17.8% in this breeder farm, respectively. The co-infection of ALV and SP was confirmed and the positive rate of both SP and ALV-P27 or ALV-A/B was 10 and 1%, respectively. There were obvious tumor nodules and lymphoid tumor cells in the comb, liver and spleen of the co-infected chickens. The degenerative and atrophic ovarian follicles, inflammatory cell infiltration in muscle biopsies were also found. The elimination rate of ALV-p27, ALV-A/B and SP positive chickens was 55.4, 13 and 6.1%, respectively. The final amount of the breeder conservation was 309 chickens. In conclusion, the co-infection of ALV-B and SP was found and more emphasis should be given on its prevention; the preliminary eradication of “ShouGuang” breeder chickens was finished.

  19. The threshold of a stochastic avian-human influenza epidemic model with psychological effect

    Science.gov (United States)

    Zhang, Fengrong; Zhang, Xinhong

    2018-02-01

    In this paper, a stochastic avian-human influenza epidemic model with psychological effect in human population and saturation effect within avian population is investigated. This model describes the transmission of avian influenza among avian population and human population in random environments. For stochastic avian-only system, persistence in the mean and extinction of the infected avian population are studied. For the avian-human influenza epidemic system, sufficient conditions for the existence of an ergodic stationary distribution are obtained. Furthermore, a threshold of this stochastic model which determines the outcome of the disease is obtained. Finally, numerical simulations are given to support the theoretical results.

  20. A modeling study of human infections with avian influenza A H7N9 virus in mainland China

    Directory of Open Access Journals (Sweden)

    Zhifei Liu

    2015-12-01

    Conclusions: Screening and culling infected poultry is a critical measure for preventing human H7N9 infections in the long term. This model may provide important insights for decision-making on a national intervention strategy for the long-term control of the H7N9 virus epidemic.

  1. Experimental infection and co-infection of dogs with Anaplasma platys and Ehrlichia canis: hematologic, serologic and molecular findings

    Directory of Open Access Journals (Sweden)

    Diniz PPVP

    2010-04-01

    Full Text Available Abstract Background Rhipicephalus sanguineus is a ubiquitous tick responsible for transmitting Ehrlichia canis and most likely Anaplasma platys to dogs, as either single or co-infections. The objective of this study was to assess the effects of either simultaneous or sequential experimental infections with E. canis and A. platys on hematological and serological parameters, duration of infection, and efficacy of doxycycline therapy in dogs infected with one or both organisms. Six dogs per group were either uninfected, A. platys infected, E. canis infected, A. platys and E. canis co-infected, A. platys infected and E. canis challenged or E. canis infected and A. platys challenged at day 112 post-infection (PI. Doxycycline treatment was initiated at 211 days PI, followed by dexamethasone immunosuppression beginning 410 days PI. Results Initially, transient decreases in hematocrit occurred in all groups infected with E. canis, but the mean hematocrit was significantly lower in the A. platys and E. canis co-infected group. All dogs except the controls developed marked thrombocytopenia after initial infection followed by gradually increased platelet counts by 112 days PI in groups with the single infections, while platelet counts remained significantly lower in the A. platys and E. canis co-infected group. Both sequential and simultaneous infections of A. platys and E. canis produced an enhanced humoral immune response to A. platys when compared to infection with A. platys alone. Likewise, co-infection with E. canis and A. platys resulted in a more persistent A. platys infection compared to dogs infected with A. platys only, but nearly all A. platys infected dogs became A. platys PCR negative prior to doxycycline treatment. E. canis infected dogs, whether single or co-infected, remained thrombocytopenic and E. canis PCR positive in blood for 420 days. When treated with doxycycline, all E. canis infected dogs became E. canis PCR negative and the

  2. No evidence of infection or exposure to Highly Pathogenic Avian Influenzas in peridomestic wildlife on an affected poultry facility

    Science.gov (United States)

    Grear, Daniel A.; Dusek, Robert J.; Walsh, Daniel P.; Hall, Jeffrey S.

    2017-01-01

    We evaluated the potential transmission of avian influenza viruses (AIV) in wildlife species in three settings in association with an outbreak at a poultry facility: 1) small birds and small mammals on a poultry facility that was affected with highly pathogenic AIV (HPAIV) in April 2015; 2) small birds and small mammals on a nearby poultry facility that was unaffected by HPAIV; and 3) small birds, small mammals, and waterfowl in a nearby natural area. We live-captured small birds and small mammals and collected samples from hunter-harvested waterfowl to test for active viral shedding and evidence of exposure (serum antibody) to AIV and the H5N2 HPAIV that affected the poultry facility. We detected no evidence of shedding or specific antibody to AIV in small mammals and small birds 5 mo after depopulation of the poultry. We detected viral shedding and exposure to AIV in waterfowl and estimated approximately 15% viral shedding and 60% antibody prevalence. In waterfowl, we did not detect shedding or exposure to the HPAIV that affected the poultry facility. We also conducted camera trapping around poultry carcass depopulation composting barns and found regular visitation by four species of medium-sized mammals. We provide preliminary data suggesting that peridomestic wildlife were not an important factor in the transmission of AIV during the poultry outbreak, nor did small birds and mammals in natural wetland settings show wide evidence of AIV shedding or exposure, despite the opportunity for exposure.

  3. Experimental infection of Hawai'i 'Amakihi (hemignathus virens) with West Nile virus and competence of a co-occurring vector, culex quinquefasciatus: potential impacts on endemic Hawaiian avifauna.

    Science.gov (United States)

    Lapointe, Dennis; Hofmeister, Erik K.; Atkinson, C.T.; Porter, R.E.; Dusek, Robert J.

    2009-01-01

    Introduced mosquito-borne avian disease is a major limiting factor in the recovery and restoration of native Hawaiian forest birds. Annual epizootics of avian pox (Avipoxvirus) and avian malaria (Plasmodium relictum) likely led to the extinction of some species and continue to impact populations of susceptible Hawaiian honeycreepers (Drepanidinae). The introduction of a novel pathogen, such as West Nile virus (WNV), could result in further population declines and extinctions. During September and October 2004, we infected Hawai'i' Amakihi (Hemignathus virens) with a North American isolate of WNV by needle inoculation and mosquito bite to observe susceptibility, mortality, and illness in this endemic passerine, and to determine the vector competence of the co-occurring, introduced mosquito Culex quinquefasciatus. All experimentally infected Hawai'i ;Amakihi became viremic, with a mean titer >10(5) plaque-forming units (PFU)/ml, and they experienced clinical signs ranging from anorexia and lethargy to ataxia. The fatality rate among needle-inoculated Hawai'i' Amakihi (n=16) was 31.3%, but mortality in free-ranging birds is likely to increase due to predation, starvation, thermal stress, and concomitant infections of avian malaria and pox. Surviving Hawai'i' Amakihi seem to clear WNV from the peripheral blood by 7-10 days postinfection (DPI), and neutralizing antibodies were detected from 9 to 46 DPI. In transmission trials, Hawaiian Cx. quinquefasciatus proved to be a competent vector and Hawai'i Amakihi an adequate amplification host of WNV, suggesting that epizootic WNV could readily become an additional limiting factor of some native Hawaiian bird populations.

  4. Storage of gastrointestinal nematode infective larvae for species preservation and experimental infections.

    Science.gov (United States)

    Chylinski, C; Cortet, J; Sallé, G; Jacquiet, P; Cabaret, J

    2015-02-01

    Techniques to preserve the infective third-stage larvae (L3) of gastrointestinal nematodes are of considerable interest to preserve rare species and to maintain a stable source for routine experimental infections. This study compares the relative pros and cons of the two most common techniques, cryopreservation and refrigeration by comparing how they influence consequent infection outcome parameters in terms of life-history traits and fitness as a function of time using the gastrointestinal nematode of sheep Haemonchus contortus as a study species. Establishment capacity was found to be significantly reduced in cryopreserved stocks of L3 compared to refrigerated stocks, but this was followed by significant increases in their fecundity. Refrigeration did not affect L3 stocks consequent fitness by 16 months (the maximum examined) although they did incur a significant reduction in establishment, followed once again by an augmentation in fecundity. The study highlights potential areas for bias in comparing studies using L3 larvae maintained for different periods of time under different techniques.

  5. Dissemination of Salmonella enteritidis by experimentally-infected pigeons

    Directory of Open Access Journals (Sweden)

    ÁH Albuquerque

    2013-09-01

    Full Text Available Two groups of domestic pigeons (Columba livia were experimentally infected orally with doses of 9.5 x10(7 and 9.5 x10(9 CFU/mL (group A and B, respectively of a Salmonella Enteritidis (SE strain isolated from chickens. None of the used doses caused mortality of the inoculated birds; however, the pathogen was successfully recovered from the liver and spleen of group B birds on day 7 post-inoculation (dpi. Pathogen shedding, as evaluated through cloacal swabs, occurred in both groups until the 14th day of observation (p <0.05. Among all fecal samples collected from group B (n=4, three different birds shed the pathogen in their feces, out of which two were positive on 3 dpi and one on 7 dpi. The same number of fecal samples was evaluated in group A and only one bird shed the pathogen, on 7 and 14 dpi. The concentration of the microorganism in the feces was lower in group A than any sample from Group B. Salmonella Enteritidis isolated from chickens, when inoculated in pigeons, may be recovered from feces, cloacal swabs and organs, and these birds may contaminate poultry causing economic losses as well as posing a risk to the public health.

  6. Haematological changes in Nile tilapia experimentally infected with Enterococcus sp.

    Directory of Open Access Journals (Sweden)

    ML. Martins

    Full Text Available This study evaluated the haematological changes in Nile tilapia experimentally infected with 1 x 10³ and 1 x 10(6 colony-forming units (CFU/mL of Enterococcus sp. in the swim bladder. The experiment consisted of four treatments in triplicates: non-injected fish (NI; fish injected with 1 mL of sterile saline solution 0.65% (SAL; fish injected with 1 x 10³ and 1 x 10(6 CFU/mL of Enterococcus diluted in 1 mL sterile saline. Twenty-four hours after injection, the fish were anesthetized and the blood collected. The haematological tests included red blood cell (RBC and white blood cell (WBC counts, hematocrit, number of total thrombocytes, and differential counting of WBC. Fish injected with 1 x 10(6 CFU/mL of Enterococcus showed a higher number of thrombocytes than the other treatments. White blood cell and lymphocyte numbers increased significantly in fish injected with 1 x 10(6 CFU/mL of Enterococcus when compared to non-injected control. There was significant increase in the number of neutrophils in saline injected fish and reduced number of monocytes after injections with 1 x 10(6 CFU/mL of Enterococcus. Hematocrit increased in fish injected with 1 x 10³ and 1 x 10(6 CFU/mL of Enterococcus.

  7. Pathology of experimental Escherichia coli infection in mice: a ...

    African Journals Online (AJOL)

    . Mice were sacrificed after 72hrs and the glands examined bacteriological and histologically. Positive bacteriological and histological results were required for a diagnosis of infection. The infective dose fifty (ID50) for the nine stereotypes ...

  8. Drug susceptibility testing of Mycobacterium Avium subsp. Avium isolates from naturally infected domestic pigeons to avian tuberculosis

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    Kaveh Parvandar

    2016-01-01

    Conclusion: We suggest drug susceptibility testing for more nontuberculous mycobateria, particularly M. avium complex isolated from infected birds and humans, as well as molecular basics of drug sensitivity in order to detect resistance genes of pathogenic M. avium subsp. avium.

  9. Genetic resistance to experimental Cooperia oncophora infections in calves

    NARCIS (Netherlands)

    Albers, G.A.A.

    1981-01-01

    The variation in resistance of cattle to gastro-intestinal nematode infection was investigated in three experiments. Bull calves, aged three months and reared under uniform conditions, were artificially infected with infective larvae of Cooperia oncophora, a moderately

  10. Performance of commercially available serological diagnostic tests to detect Leishmania infantum infection on experimentally infected dogs.

    Science.gov (United States)

    Rodríguez-Cortés, Alhelí; Ojeda, Ana; Todolí, Felicitat; Alberola, Jordi

    2013-01-31

    Leishmania infantum (syn. Leishmania chagasi) is the etiological agent of a widespread serious zoonotic disease that affects both humans and dogs. Prevalence and incidence of the canine infection are important parameters to determine the risk and the ways to control this reemergent zoonosis. Unfortunately, there is not a gold standard test for Leishmania infection. Our aim was to assess the operative validity of commercial tests used to detect antibodies to Leishmania in serum samples from experimental infections. Three ELISA tests (LEISCAN(®) Leishmania ELISA Test, INGEZIM(®) LEISHMANIA, and INGEZIM(®) LEISHMANIA VET), three immunochromatographic tests (INGEZIM(®) LEISHMACROM, SNAP(®) Leishmania, and WITNESS(®) Leishmania), and one IFAT were evaluated. LEISCAN(®) Leishmania ELISA test achieved the highest sensitivity and accuracy (both 0.98). Specificity was 1 for all tests except for IFAT. All tests but IFAT obtained a positive predictive value of 1, while the maximum negative predictive value was achieved by LEISCAN(®) Leishmania ELISA Test (0.93). The best positive likelihood ratio was obtained by INGEZIM(®) LEISHMANIA VET (30.26), while the best negative likelihood ratio was obtained by LEISCAN(®) Leishmania ELISA Test (0.02). The highest diagnostic odds ratio was achieved by LEISCAN(®) Leishmania ELISA Test (729.00). The largest area under the ROC curve was obtained by LEISCAN(®) Leishmania ELISA Test (0.981). Quantitative ELISA based tests performmed better than qualitative tests ("Rapid Tests"), and the test best suited to detect Leishmania in infected dogs and to provide clinically useful information was LEISCAN(®) Leishmania ELISA Test. This and other results point also to the need of revising the status of IFAT as a gold standard for the diagnosis of leishmaniasis. Copyright © 2012 Elsevier B.V. All rights reserved.

  11. 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...

  12. Human infections with the emerging avian influenza A H7N9 virus from wet market poultry: clinical analysis and characterisation of viral genome.

    Science.gov (United States)

    Chen, Yu; Liang, Weifeng; Yang, Shigui; Wu, Nanping; Gao, Hainv; Sheng, Jifang; Yao, Hangping; Wo, Jianer; Fang, Qiang; Cui, Dawei; Li, Yongcheng; Yao, Xing; Zhang, Yuntao; Wu, Haibo; Zheng, Shufa; Diao, Hongyan; Xia, Shichang; Zhang, Yanjun; Chan, Kwok-Hung; Tsoi, Hoi-Wah; Teng, Jade Lee-Lee; Song, Wenjun; Wang, Pui; Lau, Siu-Ying; Zheng, Min; Chan, Jasper Fuk-Woo; To, Kelvin Kai-Wang; Chen, Honglin; Li, Lanjuan; Yuen, Kwok-Yung

    2013-06-01

    Human infection with avian influenza A H7N9 virus emerged in eastern China in February, 2013, and has been associated with exposure to poultry. We report the clinical and microbiological features of patients infected with influenza A H7N9 virus and compare genomic features of the human virus with those of the virus in market poultry in Zhejiang, China. Between March 7 and April 8, 2013, we included hospital inpatients if they had new-onset respiratory symptoms, unexplained radiographic infiltrate, and laboratory-confirmed H7N9 virus infection. We recorded histories and results of haematological, biochemical, radiological, and microbiological investigations. We took throat and sputum samples, used RT-PCR to detect M, H7, and N9 genes, and cultured samples in Madin-Darby canine kidney cells. We tested for co-infections and monitored serum concentrations of six cytokines and chemokines. We collected cloacal swabs from 86 birds from epidemiologically linked wet markets and inoculated embryonated chicken eggs with the samples. We identified and subtyped isolates by RT-PCR sequencing. RNA extraction, complementary DNA synthesis, and PCR sequencing were done for one human and one chicken isolate. We characterised and phylogenetically analysed the eight gene segments of the viruses in the patient's and the chicken's isolates, and constructed phylogenetic trees of H, N, PB2, and NS genes. We identified four patients (mean age 56 years), all of whom had contact with poultry 3-8 days before disease onset. They presented with fever and rapidly progressive pneumonia that did not respond to antibiotics. Patients were leucopenic and lymphopenic, and had impaired liver or renal function, substantially increased serum cytokine or chemokine concentrations, and disseminated intravascular coagulation with disease progression. Two patients died. Sputum specimens were more likely to test positive for the H7N9 virus than were samples from throat swabs. The viral isolate from the patient

  13. Experimental infection of horses with West Nile virus.

    Science.gov (United States)

    Bunning, Michel L; Bowen, Richard A; Cropp, C Bruce; Sullivan, Kevin G; Davis, Brent S; Komar, Nicholas; Godsey, Marvin S; Baker, Dale; Hettler, Danielle L; Holmes, Derek A; Biggerstaff, Brad J; Mitchell, Carl J

    2002-04-01

    A total of 12 horses of different breeds and ages were infected with West Nile virus (WNV) via the bites of infected Aedes albopictus mosquitoes. Half the horses were infected with a viral isolate from the brain of a horse (BC787), and half were infected with an isolate from crow brain (NY99-6625); both were NY99 isolates. Postinfection, uninfected female Ae. albopictus fed on eight of the infected horses. In the first trial, Nt antibody titers reached >1:320, 1:20, 1:160, and 1:80 for horses 1 to 4, respectively. In the second trial, the seven horses with subclinical infections developed Nt antibody titers >1:10 between days 7 and 11 post infection. The highest viremia level in horses fed upon by the recipient mosquitoes was approximately 460 Vero cell PFU/mL. All mosquitoes that fed upon viremic horses were negative for the virus. Horses infected with the NY99 strain of WNV develop low viremia levels of short duration; therefore, infected horses are unlikely to serve as important amplifying hosts for WNV in nature.

  14. Molecular pathology analyses of two fatal human infections of avian influenza A(H7N9) virus.

    Science.gov (United States)

    Feng, Yanling; Hu, Lvyin; Lu, Shuihua; Chen, Qingguo; Zheng, Ye; Zeng, Dong; Zhang, Jun; Zhang, Anli; Chen, Liang; Hu, Yunwen; Zhang, Zhiyong

    2015-01-01

    To investigate the histopathological manifestations of two fatal cases of H7N9 influenza A virus infection. Pulmonary and hepatic specimens from two fatal cases of H7N9 influenza virus infection were examined using H&E staining. Additionally, in situ hybridisation was performed with probes (ViewRNA) targeting H7N9 RNA and IP-10, interleukin (IL)-6 mRNA. The distribution of surfactant protein A (SP-A), surfactant protein B (SP-B), CD3, CD4, CD8, CD68 and C4d were determined with immunohistochemistry.  Apart from the typical diffuse alveolar damage and hyaline membrane observed in severe influenza infection, we detected H7N9 RNA and massive intrapulmonary production of IP-10 and IL-6 mRNA using in situ hybridisation. Hyperplasia of type II pneumocytes was observed by H&E staining and immunohistochemistry. Proliferating macrophages and clustered neutrophils in the infected lungs were observed, whereas T lymphocytes, especially CD4T helper cells, were markedly depleted. No obvious complement deposition was found in lung tissues.  Our findings suggest that H7N9 influenza virus induced an immunological response towards overt pulmonary inflammation and systemic lymphopenia which led to intense alveolar damage and respiratory failure. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  15. The role of IL-12 in experimental Trypanosoma cruzi infection

    Directory of Open Access Journals (Sweden)

    J.S. Silva

    1998-01-01

    Full Text Available Host resistance to Trypanosoma cruzi infection is dependent on both natural and acquired immune responses. During the early acute phase of infection in mice, natural killer (NK cell-derived IFN-g is involved in controlling intracellular parasite replication, mainly through the induction of nitric oxide biosynthesis by activated macrophages. We have shown that IL-12, a powerful inducer of IFN-g production by NK cells, is synthesized soon after trypomastigote-macrophage interaction. The role of IL-12 in the control of T. cruzi infection in vivo was determined by treating infected mice with anti-IL-12 monoclonal antibody (mAb and analyzing both parasitemia and mortality during the acute phase of infection. The anti-IL-12 mAb-treated mice had higher levels of parasitemia and mortality compared to control mice. Also, treatment of infected mice with mAb specific for IFN-g or TNF-a inhibited the protective effect of exogenous IL-12. On the other hand, TGF-ß and IL-10 produced by infected macrophages inhibited the induction and effects of IL-12. Therefore, while IL-12, TNF-a and IFN-g correlate with resistance to T. cruzi infection, TGF-ß and IL-10 promote susceptibility. These results provide support for a role of innate immunity in the control of T. cruzi infection. In addition to its protective role, IL-12 may also be involved in the modulation of T. cruzi-induced myocarditis, since treatment of infected mice with IL-12 or anti-IL-12 mAb leads to an enhanced or decreased inflammatory infiltrate in the heart, respectively. Understanding the role of the cytokines produced during the acute phase of T. cruzi infection and their involvement in protection and pathogenesis would be essential to devise new vaccines or therapies.

  16. Avian malaria in New Zealand.

    Science.gov (United States)

    Schoener, E R; Banda, M; Howe, L; Castro, I C; Alley, M R

    2014-07-01

    Avian malaria parasites of the genus Plasmodium have the ability to cause morbidity and mortality in naïve hosts, and their impact on the native biodiversity is potentially serious. Over the last decade, avian malaria has aroused increasing interest as an emerging disease in New Zealand with some endemic avian species, such as the endangered mohua (Mohua ochrocephala), thought to be particularly susceptible. To date, avian malaria parasites have been found in 35 different bird species in New Zealand and have been diagnosed as causing death in threatened species such as dotterel (Charadrius obscurus), South Island saddleback (Philesturnus carunculatus carunculatus), mohua, hihi (Notiomystis cincta) and two species of kiwi (Apteryx spp.). Introduced blackbirds (Turdus merula) have been found to be carriers of at least three strains of Plasmodium spp. and because they are very commonly infected, they are likely sources of infection for many of New Zealand's endemic birds. The spread and abundance of introduced and endemic mosquitoes as the result of climate change is also likely to be an important factor in the high prevalence of infection in some regions and at certain times of the year. Although still limited, there is a growing understanding of the ecology and epidemiology of Plasmodium spp. in New Zealand. Molecular biology has played an important part in this process and has markedly improved our understanding of the taxonomy of the genus Plasmodium. This review presents our current state of knowledge, discusses the possible infection and disease outcomes, the implications for host behaviour and reproduction, methods of diagnosis of infection, and the possible vectors for transmission of the disease in New Zealand.

  17. Ecology and conservation biology of avian malaria

    Science.gov (United States)

    LaPointe, Dennis A.; Atkinson, Carter T.; Samuel, Michael D.

    2012-01-01

    Avian malaria is a worldwide mosquito-borne disease caused by Plasmodium parasites. These parasites occur in many avian species but primarily affect passerine birds that have not evolved with the parasite. Host pathogenicity, fitness, and population impacts are poorly understood. In contrast to continental species, introduced avian malaria poses a substantial threat to naive birds on Hawaii, the Galapagos, and other archipelagoes. In Hawaii, transmission is maintained by susceptible native birds, competence and abundance of mosquitoes, and a disease reservoir of chronically infected native birds. Although vector habitat and avian communities determine the geographic distribution of disease, climate drives transmission patterns ranging from continuous high infection in warm lowland forests, seasonal infection in midelevation forests, and disease-free refugia in cool high-elevation forests. Global warming is expected to increase the occurrence, distribution, and intensity of avian malaria across this elevational gradient and threaten high-elevation refugia, which is the key to survival of many susceptible Hawaiian birds. Increased temperatures may have already increased global avian malaria prevalence and contributed to an emergence of disease in New Zealand.

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

    African Journals Online (AJOL)

    The pathological effect of coccidiosis on sperm production of the male chickens had not been previously studied. It is note-worthy that coccidiosis infection in broiler males showed no degenerative changes in the seminiferous tubules and testis. In both cross and longitudinal sections of the testis of the infected male, there ...

  19. Experimental infection of squirrel monkeys with nipah virus.

    Science.gov (United States)

    Marianneau, Philippe; Guillaume, Vanessa; Wong, Thong; Badmanathan, Munisamy; Looi, Ren Yih; Murri, Severine; Loth, Philippe; Tordo, Noel; Wild, Fabian; Horvat, Branka; Contamin, Hugues

    2010-03-01

    We infected squirrel monkeys (Saimiri sciureus) with Nipah virus to determine the monkeys' suitability for use as primate models in preclinical testing of preventive and therapeutic treatments. Infection of squirrel monkeys through intravenous injection was followed by high death rates associated with acute neurologic and respiratory illness and viral RNA and antigen production.

  20. Variations in virulence of avian pathogenic Escherichia coli demonstrated by the use of a new in vivo infection model

    DEFF Research Database (Denmark)

    Pors, Susanne Elisabeth; Olsen, Rikke Heidemann; Christensen, Jens Peter

    2014-01-01

    , E. coli was found in pure culture from one or more positions in the oviduct and the liver. Birds receiving sterile broth did not culture positive and demonstrated no gross lesions. Subsequently, 19 birds were inoculated with an isolate of E. coli ST95 and 20 birds with an isolate of E. coli ST141....... Major variation in virulence was observed between the two isolates used in relation to clinical signs, gross lesions and histopathology. In contrast to E. coli ST141, E. coli ST95 caused severe clinical signs, epithelial necrosis of the oviduct and purulent salpingitis. The results of the study show...... of the oviduct, five birds were inoculated with 8.6 × 10(6)CFU of a clinical Escherichia coli isolate. Five control birds received broth with no bacteria. Both infected and control birds were euthanized after 48 h followed by a post mortem examination. Infected birds showed diffuse fibrino-purulent peritonitis...

  1. Preferential infection sites of Cysticercus bovis in cattle experimentally infected with Taenia saginata eggs.

    Science.gov (United States)

    Lopes, Welber D Z; Santos, Thaís R; Soares, Vando E; Nunes, Jorge L N; Mendonça, Rafael P; de Lima, Roberto C A; Sakamoto, Cláudio A M; Costa, Gustavo H N; Thomaz-Soccol, Vanete; Oliveira, Gilson P; Costa, Alvimar J

    2011-02-01

    The preferential sites of infection of Cysticercus bovis were evaluated in the skeletal muscle and entrails of 25 cattle that were experimentally infected with Taenia saginata (2×10(4) eggs). Two other animals were not inoculated (control). Ninety days after inoculation, all the cattle were euthanized. The carcasses were deboned and dissected into 26 anatomical sections (masseter muscles, brain, tongue, esophagus, heart, diaphragm, lungs, liver, kidneys, spleen, top sirloin butt, bottom sirloin butt, outside round, top (inside) round, transversus abdominus, top sirloin cap, strip loin, full tenderloin, eye of round, knuckle, shoulder clod, foreshank, shank, chuck, back ribs, and tail muscles). The dissected tissues were sliced into 5mm sections. From the 25 cattle, 9258 C. bovis (cysticerci) were recovered; 75.02% (6946) of these were recovered from skeletal muscles and 24.98% (2312) from the entrails. A high parasitism level was found in the shoulder clod (12.55%), heart (11.02%), liver (9.48%), masseter muscles (8.51%), chuck (8.25%), strip loin and full tenderloin (7.26%), knuckle (6.63%), and back ribs (5.53%), totaling 69.23% (5738) of all of the detected cysticerci. On the other hand, there was a low C. bovis parasitism level in the brain, spleen, tail muscles, kidneys, esophagus, and diaphragm, representing just 3.9% of the total number of cysticerci. Given these results, we conclude that specific skeletal musculature regions, such as the shoulder blade, chuck, strip loin and full tenderloin, knuckle, back ribs and top round, which are not officially examined in many countries, are effective sites to efficiently screen C. bovis infection. To date, these regions have not been considered as preferential sites of C. bovis infection. Based on our work, however, these regions deserve greater attention from health inspectors because they contained a greater number of Cysticercus than the other regions of carcasses that are parasitized by T. saginata larvae

  2. Experimental fetal and transplacental Neospora infection in the nonhuman primate.

    Science.gov (United States)

    Barr, B C; Conrad, P A; Sverlow, K W; Tarantal, A F; Hendrickx, A G

    1994-08-01

    Neospora is a newly recognized Toxoplasma-like protozoan that causes spontaneous abortion and/or neonatal disease in a wide range of animals. The purpose of this study was to determine the susceptibility of primates to Neospora infection. In experiment 1, two rhesus macaque fetuses were inoculated in utero at gestational day 65 with 1 x 10(6) culture-derived Neospora tachyzoites. A control fetus was given uninfected vehicle. The fetuses were removed by hysterotomy between 13 and 22 days postinoculation. In experiment 2, two pregnant macaques were inoculated intramuscularly and intravenously on gestational day 43 with a total of 1.6 x 10(7) culture-derived tachyzoites. A pregnant control macaque was given uninfected vehicle. The fetuses were removed by hysterotomy between 67 to 70 days postinoculation. Fetal tissues were collected for in vitro parasite isolation, histopathology, and Neospora immunohistochemistry. Fetal blood was examined for Neospora-specific antibody titers using an indirect fluorescent antibody test. Neospora infections were confirmed in all fetuses that received tachyzoites either directly or via transplacental infection. In experiment 1, infected fetuses had reduced amniotic fluid volumes, marked protozoal amnionitis and dermatitis, and a mild multifocal encephalitis. Infected fetuses from experiment 2 had a chronic multifocal necrotizing nonsuppurative meningoencephalitis with microcavitation, that was confined to the cerebrum, and a mild multifocal necrotizing amnionitis. In both experiments, Neospora tachyzoites were detected in association with lesions in fetal tissues by immunohistochemistry, and the parasites were reisolated in vitro. IgG Neospora antibody titers were detected in blood from all infected fetuses, whereas Neospora-specific IgM and IgA titers were found in one and three fetuses, respectively. Results indicate that nonhuman primates are susceptible to transplacental Neospora infection. The fetal lesions after transplacental

  3. Avian Influenza (Bird Flu)

    Science.gov (United States)

    ... Submit What's this? Submit Button Archived Flu Emails Influenza Types Seasonal Avian Swine/Variant Pandemic Other Information on Avian Influenza Language: English (US) Español Recommend on Facebook Tweet ...

  4. Avian respiratory system disorders

    Science.gov (United States)

    Olsen, G.H.

    1989-01-01

    Diagnosing and treating respiratory diseases in avian species requires a basic knowledge about the anatomy and physiology of this system in birds. Differences between mammalian and avian respiratory system function, diagnosis, and treatment are highlighted.

  5. Experimental infection of pregnant gilts with swine hepatitis E virus

    OpenAIRE

    Kasorndorkbua, Chaiyan; Thacker, Brad J.; Halbur, Patrick G.; Guenette, Denis K.; Buitenwerf, Ryan M.; Royer, Ryan L.; Meng, Xiang-Jin

    2003-01-01

    To determine the effect of swine hepatitis E virus (HEV) infection on pregnant gilts, their fetuses, and offspring, 12 gilts were intravenously inoculated with swine HEV. Six gilts, who were not inoculated, served as controls. All inoculated gilts became actively infected and shed HEV in feces, but vertical transmission was not detected in the fetuses. There was no evidence of clinical disease in the gilts or their offspring. Mild multifocal lymphohistiocytic hepatitis was observed in 4 of 12...

  6. Characterizing the histopathology of natural co-infection with Marek's disease virus and subgroup J avian leucosis virus in egg-laying hens.

    Science.gov (United States)

    Wen, Yawen; Huang, Qi; Yang, Chengcheng; Pan, Ling; Wang, Guijun; Qi, Kezong; Liu, Hongmei

    2018-02-01

    Marek's disease virus (MDV) and avian leucosis virus (ALV) are known to cause tumours in egg-laying hens. Here, we investigated the aetiology of tumours in a flock of egg-laying hens vaccinated against MDV. We carried out gross pathology and histopathological examinations of the diseased tissues, identified virus antigen and sequenced viral oncogenes to elucidate the cause of death in 21-22-week-old hens. At necropsy, diseased hens had distinctly swollen livers, spleens, and proventriculus, and white tumour nodules in the liver. The spleen and liver had been infiltrated by lymphoid tumour cells, while the proventriculus had been infiltrated by both lymphoid tumour cells and myeloblastic cells. Subtype J ALV (ALV-J) and MDV were widely distributed in the proventricular gland cells, and the lymphoid tumour cells in the liver and the spleen. In addition, positive ALV-J signals were also observed in parts of the reticular cells in the spleen. MDV and ALV-J antigens were observed in the same foci of the proventricular gland cells; however, the two antigens were not observed in the same foci from the spleen and liver. The amino acid sequence of the AN-1 (the representative liver tumour tissue that was positive for both ALV-J and MDV) Meq protein was highly similar to the very virulent MDV QD2014 from China. Compared to the ALV-J HPRS-103 reference strain, 10 amino acids (224-CTTEWNYYAY-233) were deleted from the gp85 protein of AN-1. We concluded that concurrent infection with MDV and ALV-J contributed to the tumorigenicity observed in the flock.

  7. Manipulation of male attractiveness induces rapid changes in avian maternal yolk androgen deposition

    NARCIS (Netherlands)

    Kingma, Sjouke A.; Komdeur, Jan; Vedder, Oscar; Engelhardt, Nikolaus von; Korsten, Peter; Groothuis, Ton G.G.

    2009-01-01

    Avian eggs contain maternal androgens that may adjust offspring development to environmental conditions. We review evidence and functional explanations for the relationship between androgen concentrations in avian eggs and male attractiveness. Experimental studies in captive birds show generally

  8. Histopathological evaluation of the efficacy of antifungals for experimental Trichosporon bloodstream infection.

    Science.gov (United States)

    Sasai, Daisuke; Okubo, Yoichiro; Ishiwatari, Takao; Sugita, Takashi; Kaneko, Takehiko; Murayama, Somay Yamagata; Shimamura, Tsuyoshi; Shinozaki, Minoru; Hasegawa, Chikako; Mitsuda, Aki; Tochigi, Naobumi; Wakayama, Megumi; Nemoto, Tetsuo; Shibuya, Kazutoshi

    2013-01-01

    The efficacy of polyene macrolides to treat experimental Trichosporon bloodstream infection was evaluated by histopathological examination and viable cell counts in the kidneys of infected mice. Viable cell counts on the 5th day after infection confirmed that liposomal amphotericin B (L-AMB) is a more effective treatment than fluconazole (FLC) for mice infected with an azole-resistant strain of Trichosporon. Histological examination revealed that the administration of L-AMB induced a transformation from acute purulent inflammation caused by both azole-susceptible and -resistant strain infections to a chronic and subsiding form, whereas FLC failed to convert the acute inflammation induced by the azole-resistant strain to a subsiding form. Our results demonstrate that polyene macrolides can be used as an alternative therapy for infection of azole-resistant strains of Trichosporon and that histopathological evaluation is useful for elucidating the pathophysiology of an experimental Trichosporon infection.

  9. Avian influenza virus

    Science.gov (United States)

    Avian influenza virus (AIV) is type A influenza that is adapted to avian host species. Although the virus can be isolated from numerous avian species, the natural host reservoir species are dabbling ducks, shorebirds and gulls. Domestic poultry species (poultry being defined as birds that are rais...

  10. Avian Influenza a (H5N1 Infection with Respiratory Failure and Meningoencephalitis in a Canadian Traveller

    Directory of Open Access Journals (Sweden)

    Naheed Rajabali

    2015-01-01

    Full Text Available In an urban centre in Alberta, an otherwise healthy 28-year-old woman presented to hospital with pleuritic chest and abdominal pain after returning from Beijing, China. After several days, this was followed by headache, confusion and, ultimately, respiratory failure, coma and death. Microbiology yielded influenza A subtype H5N1 from various body sites and neuroimaging was consistent with meningoencephalitis. While H5N1 infections in humans have been reported in Asia since 1997, this is the first documented case of H5N1 influenza in the Western Hemisphere. The present case demonstrated the typical manifestation of H5N1 influenza but, for the first time, also confirmed previous suggestions from human and animal studies that H5N1 is neurotropic and can manifest with neurological symptoms and meningoencephalitis.

  11. [Experimental and natural infection with the enzootic leukosis virus of cattle].

    Science.gov (United States)

    Hofírek, B; Horín, P; Granátová, M; Machatková, M; Franz, J; Svoboda, I; Blecha, J

    1986-03-01

    A trial was performed with heifers at the age of six to seven months. The animals were experimentally infected with the lymphocytes of a virus-productive donor. Infection was produced in all the nine cases, as demonstrated by means of the positive syncytial test. As indicated by the results of the trial, the antibodies to the enzootic bovine leucosis virus (BLV) were produced soon after experimental infection. A high sensitivity of the serum-neutralization test and the ELISA method was demonstrated in this connection: by these methods, the antibodies were identified already two to three weeks after experimental infection whereas by the immunodiffusion test they could be detected only after five weeks. Twenty-four animals were exposed to natural contact infection. Within 270 days of the trial, the disease after contact was recorded only in one heifer out of the four that were in close contact with the experimentally infected animals. In this case, as compared with experimental infection, the antibodies were produced much later--after 85 to 93 days. Leucosis was recorded in none of the remaining animals. The reasons why such a favourable result was obtained were the thorough disinfection of the stables after blood collections and the strict observance of the aseptic conditions. The results of experimental infection in three cows were identical with those obtained in young cattle. In the experimentally infected dairy cows, antibodies in milk were determined by the ELISA method. As found, in milk the antibodies to BLV appear two to three weeks later than they do in serum. The ELISA method of BLV antibody detection can be used for the identification of infected animals in herds where enzootic bovine leucosis occurs.

  12. Using experimental human influenza infections to validate a viral dynamic model and the implications for prediction.

    Science.gov (United States)

    Chen, S C; You, S H; Liu, C Y; Chio, C P; Liao, C M

    2012-09-01

    The aim of this work was to use experimental infection data of human influenza to assess a simple viral dynamics model in epithelial cells and better understand the underlying complex factors governing the infection process. The developed study model expands on previous reports of a target cell-limited model with delayed virus production. Data from 10 published experimental infection studies of human influenza was used to validate the model. Our results elucidate, mechanistically, the associations between epithelial cells, human immune responses, and viral titres and were supported by the experimental infection data. We report that the maximum total number of free virions following infection is 10(3)-fold higher than the initial introduced titre. Our results indicated that the infection rates of unprotected epithelial cells probably play an important role in affecting viral dynamics. By simulating an advanced model of viral dynamics and applying it to experimental infection data of human influenza, we obtained important estimates of the infection rate. This work provides epidemiologically meaningful results, meriting further efforts to understand the causes and consequences of influenza A infection.

  13. Cardiac plexus of dogs experimentally infected with Trypanosoma cruzi: inflammatory lesions and quantitative studies

    Directory of Open Access Journals (Sweden)

    Marcelo V. Caliari

    1995-03-01

    Full Text Available Qualitative and quantitative aspects of the superficial and profound cardiac plexus of dogs experimentally infected with Be-62 and Be-78 strains of Trypanosoma cruzi were studied. Animals were autopsied in the acute phase of infection. The inflammatory process, lesions and number of parasites were more intense and frequent in animals infected with the Be-78 strain than in those infected with Be-62. Despite this, no statistically significant differences could be found between the number of neuron bodies in the ganglia of infected and control dogs.

  14. Transcriptome-wide characterization of human cytomegalovirus in natural infection and experimental latency.

    Science.gov (United States)

    Cheng, Shu; Caviness, Katie; Buehler, Jason; Smithey, Megan; Nikolich-Žugich, Janko; Goodrum, Felicia

    2017-11-20

    The transcriptional program associated with herpesvirus latency and the viral genes regulating entry into and exit from latency are poorly understood and controversial. Here, we developed and validated a targeted enrichment platform and conducted large-scale transcriptome analyses of human cytomegalovirus (HCMV) infection. We used both an experimental hematopoietic cell model of latency and cells from naturally infected, healthy human subjects (clinical) to define the breadth of viral genes expressed. The viral transcriptome derived from experimental infection was highly correlated with that from clinical infection, validating our experimental latency model. These transcriptomes revealed a broader profile of gene expression during infection in hematopoietic cells than previously appreciated. Further, using recombinant viruses that establish a nonreactivating, latent-like or a replicative infection in CD34+ hematopoietic progenitor cells, we defined classes of low to moderately expressed genes that are differentially regulated in latent vs. replicative states of infection. Most of these genes have yet to be studied in depth. By contrast, genes that were highly expressed, were expressed similarly in both latent and replicative infection. From these findings, a model emerges whereby low or moderately expressed genes may have the greatest impact on regulating the switch between viral latency and replication. The core set of viral genes expressed in natural infection and differentially regulated depending on the pattern of infection provides insight into the HCMV transcriptome associated with latency in the host and a resource for investigating virus-host interactions underlying persistence.

  15. Avian Influenza in Migratory Birds : Regional Surveillance and ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    This grant will allow APAIR to establish a multi-country surveillance network to detect, characterize and report avian influenza infections in migratory birds. The project is expected to improve early warning on the spread of avian influenza in the region, and provide a better understanding of the role of wild bird species in ...

  16. First attempt to produce experimental Campylobacter concisus infection in mice

    DEFF Research Database (Denmark)

    Aabenhus, R.; Stenram, U.; Andersen, L.P.

    2008-01-01

    AIM: To infect mice with atypical Campylobacter concisus (C. concisus) for the first time. METHODS: Three separate experiments were conducted in order to screen the ability of five clinical C. concisus isolates of intestinal origin and the ATCC 33237 type strain of oral origin to colonize...

  17. Experimental toxoplasma gondii infection in grey seals (Halichoerus grypus)

    DEFF Research Database (Denmark)

    Gajadhar, A. A.; Measures, L.; Forbes, L. B.

    2004-01-01

    Laboratory-reared animals were used to assess the susceptibility of seals (Halichoerus grypus) to Toxoplasma gondii infection. Four seals were each orally inoculated with 100 or 10,000 oocysts of T. gondii (VEG strain), and another 4 seals served as negative controls. Occasionally, mild behavioral...

  18. 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...

  19. 0f chemotherapy in goats experimentally infected with

    African Journals Online (AJOL)

    'Y58' stock. The goats were monitored serologically by using antigen-ELISA and Antibody-ELISA before and after Berenil treatment for a period lasting about sixty two days. The mean prepatent period before trypanosomes were detected in their bloodstreams was five days post-infection; circulating antigens and antibodies ...

  20. Salmonella Enteritidis experimental infection in chickens: Effects of ...

    African Journals Online (AJOL)

    Salmonella enterica serovar Enteritidis is a food borne pathogen of humans causing food-poisoning and sometimes deaths. In order to control egg-borne transmission of Salmonella Enteritidis to humans, prompt and accurate detection of infected poultry flocks is essential. This paper examined the effects of challenge dose ...

  1. Histopathological changes during experimental infections of calves with Cooperia punctata.

    Science.gov (United States)

    Rodrigues, R R; Gennari, S M; Guerra, J L; Contieri, M B; Abdalla, A L; Vitti, D M S S

    2004-06-01

    Eleven male two-month-old Holstein calves were used to determine the pathological changes induced by a Cooperia punctata infection. After weaning, ten calves received a single oral dose of 45,000 C. punctata infective larvae. One calf remained as a non-infected control. Groups of two calves were killed on days 7, 14, 21, 28 and 35 post-infection (p.i.) for determination of worm burdens and histopathological evaluation. The small intestine was sub-divided into three sections of approximately equal length, and representative samples of mucosa were fixed in 10% formalin, cut, and stained with haematoxylin-eosin. Samples of intestinal contents and mucosal digests were taken and fixed in 10% formalin for an estimation of total worm burdens. An increase in the number of adult parasites and a decrease in the number of larvae were observed with time (P<0.001). A higher concentration of worms was found in the first segment of the small intestine during the five weeks of observation. Histology showed larvae in the intestinal mucosa on day 7 p.i., with a discrete increase in the cellular response. Adult worms and a marked cellular infiltrate with eosinophils and neutrophils were present on day 21 p.i., and these persisted until day 35 p.i. Microcysts resulting from worm destruction were observed from day 21 p.i.

  2. Experimental infection of Ethiopian highland sheep by different ...

    African Journals Online (AJOL)

    concentration, RBC counts and PCV values between exotic and indigenous animals but these physiological values were not recorded for different species and breeds of indigenous animals in Ethiopia. Information is also lacking about the effects of GI nematodes infection on these physiological parameters. (Bekele Tafesse ...

  3. Effects of experimental Neisseria meningitis W135 infection on ...

    African Journals Online (AJOL)

    This study investigated the effects of Neisseria menigitidis W135 infection via intraperitoneal route on plasma free tryptophan concentration, brain serotonin and 5-hydroxyindole acetic acid (5-HIAA) levels in albino mice fed normal and tryptophan-enriched diets. The kinetics of appearance of viable bacteria in the blood, ...

  4. Early stage leucocytosis in Nigerian pigs experimentally infected ...

    African Journals Online (AJOL)

    Sequential leukocyte changes associated with early phase of Trypanosoma brucei infection were investigated in indigenous Nigerian pigs. This was with the view to providing further hematological basis for effective chemotherapy of natural porcine trypanosomosis and to assessing the possible roles of leukocytes in ...

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Science.gov (United States)

    Zhao, Tong-Mao; Hague, Bishop; Caudell, David L; Simpson, R Mark; Kindt, Thomas J

    2005-01-01

    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. PMID:15910683

  7. Recrudescent Campylobacter jejuni infection in an immunocompetent adult following experimental infection with a well-characterized organism.

    Science.gov (United States)

    Baqar, Shahida; Tribble, David R; Carmolli, Marya; Sadigh, Katrin; Poly, Frederic; Porter, Chad; Larsson, Catherine J; Pierce, Kristen K; Guerry, Patricia; Darsley, Michael; Kirkpatrick, Beth

    2010-01-01

    The recrudescence of infection with Campylobacter jejuni after appropriate antibiotic treatment has not been previously reported in an immunocompetent adult. We present the complete clinical, microbiologic, and immunologic evaluation of a closely monitored healthy male with recrudescent C. jejuni infection occurring in the absence of immunodeficiency following experimental infection with a well-characterized strain. After antibiotic treatment, the initial infection was clinically cleared and microbiologically undetectable. Subsequently, two episodes of recrudescence occurred, with no change in in vitro antibiotic sensitivity being detected. The immune responses of the individual were compared to those of other participants in the experimental infection study: innate immune responses, including fecal cytokines and C-reactive protein, were intact; however, measures of Campylobacter-specific adaptive immune responses were absent, including serum antibodies, antibody-secreting cells, and in vitro gamma interferon responses. No primary or secondary immunodeficiency was identified. Recrudescent Campylobacter infections after treatment may be more common than has previously been appreciated. This work adds to our understanding of the human immune response to natural Campylobacter infection and reiterates the importance of pathogen-specific adaptive immune responses to this globally important pathogen.

  8. Recrudescent Campylobacter jejuni Infection in an Immunocompetent Adult following Experimental Infection with a Well-Characterized Organism▿ †

    Science.gov (United States)

    Baqar, Shahida; Tribble, David R.; Carmolli, Marya; Sadigh, Katrin; Poly, Frederic; Porter, Chad; Larsson, Catherine J.; Pierce, Kristen K.; Guerry, Patricia; Darsley, Michael; Kirkpatrick, Beth

    2010-01-01

    The recrudescence of infection with Campylobacter jejuni after appropriate antibiotic treatment has not been previously reported in an immunocompetent adult. We present the complete clinical, microbiologic, and immunologic evaluation of a closely monitored healthy male with recrudescent C. jejuni infection occurring in the absence of immunodeficiency following experimental infection with a well-characterized strain. After antibiotic treatment, the initial infection was clinically cleared and microbiologically undetectable. Subsequently, two episodes of recrudescence occurred, with no change in in vitro antibiotic sensitivity being detected. The immune responses of the individual were compared to those of other participants in the experimental infection study: innate immune responses, including fecal cytokines and C-reactive protein, were intact; however, measures of Campylobacter-specific adaptive immune responses were absent, including serum antibodies, antibody-secreting cells, and in vitro gamma interferon responses. No primary or secondary immunodeficiency was identified. Recrudescent Campylobacter infections after treatment may be more common than has previously been appreciated. This work adds to our understanding of the human immune response to natural Campylobacter infection and reiterates the importance of pathogen-specific adaptive immune responses to this globally important pathogen. PMID:19923572

  9. Experimental treatment with sodium stibogluconate of hamsters infected with Leishmania (Leishmania) chagasi and Leishmania (Leishmania) amazonensis

    OpenAIRE

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

    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 ...

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

    Directory of Open Access Journals (Sweden)

    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

  11. 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 ...... could be identified in tissue sections by immunostaining. Immunohistochemically, B, licheniformis was demonstrated in hepatic and pulmonic macrophages, and from some animals the bacteria were also reisolated....

  12. 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.

  13. Experimental challenge of chicken vaccinated with commercially available H5 vaccines reveals loss of protection to some highly pathogenic avian influenza H5N1 strains circulating in Hong Kong/China.

    Science.gov (United States)

    Connie Leung, Y H; Luk, Geraldine; Sia, Sin-Fun; Wu, Yu-On; Ho, Chuk-Kwan; Chow, Kai-Chi; Tang, Shing-Chun; Guan, Yi; Malik Peiris, J S

    2013-08-02

    Highly pathogenic avian influenza (HPAI) H5N1 virus continues to circulate in poultry in Asia and Africa posing a threat to both public and animal health. Vaccination, used as an adjunct to improved bio-security and stamping-out policies, contributed to protecting poultry in Hong Kong from HPAI H5N1 infection in 2004-2008 although the virus was repeatedly detected in dead wild birds. The detection of clade 2.3.4 H5N1 viruses in poultry markets and a farm in Hong Kong in 2008 raised the question whether this virus has changed to evade protection from the H5 vaccines in use. We tested the efficacy of three commercial vaccines (Nobilis, Poulvac and Harbin Re-5 vaccine) in specific pathogen free white leghorn chickens against a challenge with A/chicken/Hong Kong/8825-2/2008 (clade 2.3.4) isolated from vaccinated poultry in Hong Kong and A/chicken/Hong Kong/782/2009 (clade 2.3.2). Harbin Re5 vaccine provided the best, albeit not complete protection against challenge with the clade 2.3.4 virus. All three vaccines provided good protection from death and significantly reduced virus shedding following challenge with the clade 2.3.2 virus. Only Harbin Re-5 was able to completely protect chickens from virus shedding as well as mortality. Sera from vaccinated chickens had lower geometric hemagglutination inhibition titers against A/chicken/Hong Kong/8825-2/08, as compared to two other clade 2.3.4 and one clade 0 virus. Alignment of amino-acid sequences of the haemagglutinin of A/chicken/Hong Kong/8825-2/08 and the other H5 viruses revealed several mutations in positions including 69, 71, 83, 95, 133,140, 162, 183, 189, 194 and 270 (H5 numbering) which may correlate with loss of vaccine protection. Our results indicated that the tested HPAI H5N1 (2.3.4) virus has undergone antigenic changes that allow it to evade immunity from poultry vaccines. This highlights the need for continued surveillance and monitoring of vaccine induced immunity, with experimental vaccine challenge

  14. Serum levels of mannan-binding lectin in chickens prior to and during experimental infection with avian infectious bronchitis virus

    DEFF Research Database (Denmark)

    Juul-Madsen, H.R.; Munch, M.; Handberg, Kurt

    2003-01-01

    Mannan-binding lectin (MBL) is a glycoprotein and a member of the C-type lectin super family, the collectin family, and the acute phase protein family. The MBL exerts its function by directly binding to microbial surfaces through its carbohydrate recognition domains, followed by direct opsonization......, the highest value was found in chickens inoculated after 12 h of activity. Thus, an inverse relation exists between the MBL response and the IBV specific antibody response. The ability of MBL to activate the complement cascade was tested in a heterologous system by deposition of human C4 on the chicken MBL...

  15. 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.

  16. Coxsackievirus infections in pregnant women with a parallel experimental model infection showing possible effects on coarse of pregnancy

    Directory of Open Access Journals (Sweden)

    Borsanyiova M.

    2011-04-01

    Full Text Available Aim of our work was firstly to determine the prevalence of anti-coxsackievirus antibodies during pregnancy. 217 serum samples were tested for antibodies by virus neutralization test against coxsackieviruses (CV B1–B6, A7 and A9. The second aim was to investigate experimental transmission of virus to the fetus during pregnancy. Methods. Virus Neutralization Test, RT-PCR. Results. In the serological study, paired blood serum samples from 217 pregnant women were studied for antibodies against coxsackievirus serotypes (CVB1–CVB6, CVA7 and CVA9 in sera of pregnant women from selected areas of the Slovak Republic. Coxsackievirus B4 (CVB4 infection was most prevalent, followed by CVB3, CVA7, CVA9, CVB5, CVB2, CVB1 while coxsackievirus B6 (CVB6 was scarce. In 30 out of 217 cases (13.82 % current infection was recorded. In the experimental murine study, in the second week of gravidity we observed presence of enteroviral RNA in the placenta and the intestine of the dead fetuses of the mice. Conclusions. Anti-CV antibodies were prevalent in the pregnant mothers indicating circulation of these viruses in the population. Current infection was shown in 13.82 % of studied cases. Presence of virus RNA in the organs of the unborn fetuses in the experimental infection indicates the possibility of transfer of the coxsackievirus B4-E2 infection from mother to child during antenatal development

  17. Study of the pathogenic potential of Dientamoeba fragilis in experimentally infected mice

    Directory of Open Access Journals (Sweden)

    Eman K. El-Gayar

    2016-06-01

    Full Text Available Dientamoebafragilis (D. fragilis is a protozoan parasite whose pathogenic potential is still disputable. The aim of this study was to illustrate the pathogenicity of D. fragilis infection and to determine the infective dose for experimental mice infection. Three groups of mice (8/each were orally inoculated with in vitro cultured D. fragilis. The infected groups (G1- G3 received 103, 105 and 4 × 106 D. fragilis/0.5 ml culture, respectively. A control group (G4 only received parasite-free culture. Two weeks post-inoculation all mice were euthanized for histopathological examination. All mice of G3 (100% and three mice of G2 (37.5% were infected, and the results were confirmed by PCR and different staining methods. On the other hand, all mice from group G1 showed a completely negative result. Histopathological examination of the colon and caecum of the highly infected group G3 showed active colitis, with infiltration of mixed inflammatory cells such as eosinophils, neutrophils and lymphocytes within the lamina propria of the intestinal wall. The parasite was not invading the colonic mucosa. This study revealed that infection with D. fragilis is dose-dependent. Moreover, a dose of 105 D. fragilis/mouse or higher is necessary to infect mice through the oral route. In addition, this route of infection, although non-invasive, can induce severe inflammatory changes to the colonic and caecal mucosa in experimentally infected mice.

  18. Experimental Trypanosoma evansi infection in South American coati (Nasua nasua): hematological, biochemical and histopathological changes.

    Science.gov (United States)

    Herrera, H M; Alessi, A C; Marques, L C; Santana, A E; Aquino, L P C T; Menezes, R F; Moraes, M A V; Machado, R Z

    2002-03-01

    The course of an experimental Trypanosoma evansi infection in coatis (Nasua nasua, carnivora, Procyonidae) was followed for 262 days. Hematological analysis of the infected coatis revealed a marked decline in hemoglobin, packed-cell volume, and total erythrocyte count. An intense anemia followed the first wave of parasitemia and persisted until the end of the experimental period. Biochemical analysis showed increased serum levels of alanine aminotransferase and aspartate aminotransferase and decreased albumin. The main histopathological features consisted of myocarditis with the presence of degenerate cardiac fibers and meningoencephalitis. This study has shown that coatis infected with T. evansi develop a chronic disease.

  19. 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...... 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...

  20. Experimental Infection of Cats and Dogs with West Nile Virus

    OpenAIRE

    Austgen, Laura E.; Bowen, Richard A.; Bunning, Michel L.; Davis, Brent S.; Mitchell, Carl J.; Chang, Gwong-Jen J.

    2004-01-01

    Domestic dogs and cats were infected by mosquito bite and evaluated as hosts for West Nile virus (WNV). Viremia of low magnitude and short duration developed in four dogs but they did not display signs of disease. Four cats became viremic, with peak titers ranging from 103.0 to 104.0 PFU/mL. Three of the cats showed mild, non-neurologic signs of disease. WNV was not isolated from saliva of either dogs or cats during the period of viremia. An additional group of four cats were exposed to WNV o...

  1. Immunobiological characterization of Graphidium strigosum experimental infection in rabbits (Oryctolagus cuniculus).

    Science.gov (United States)

    Cuquerella, M; Alunda, J M

    2009-01-01

    An experimental infection of rabbits with a wild isolate of the gastric nematode Graphidium strigosum was carried out. Animals (3.5 months age) were infected with 1,000 L3 administered by bucoesophagic catheter (five rabbits) or kept as uninfected control group (five animals). The infection was maintained for 3 months. Along the experimental period, some parasitological, hematological and immunological parameters were determined. Prepatent period of the infection ranged from 30 to 38 days and, at necropsy, average adult helminth counts were 430.75 +/- 126.12. No significant variations were found in packed cell volume, leukocyte, and eosinophil counts along the experimental period. Infection elicited a clear serum-specific IgG response, estimated by ELISA, during patency. Pooled sera from the patent period of the infection recognized some soluble antigens, particularly, a 67-kDa protein. Experimentally infected animals did not show cross recognition between G. strigosum, Haemonchus contortus, and Teladorsagia circumcincta. However, Western blot analysis with hyperimmune sera against H. contortus raised in rabbits and lambs showed cross reactivity between this helminth species and G. strigosum.

  2. Experimental infection of raccoons (Procyon lotor) with West Nile virus.

    Science.gov (United States)

    Root, J Jeffrey; Bentler, Kevin T; Nemeth, Nicole M; Gidlewski, Thomas; Spraker, Terry R; Franklin, Alan B

    2010-10-01

    To characterize the responses of raccoons to West Nile virus (WNV) infection, we subcutaneously exposed them to WNV. Moderately high viremia titers (≤ 10(4.6) plaque forming units [PFU]/mL of serum) were noted in select individuals; however, peak viremia titers were variable and viremia was detectable in some individuals as late as 10 days post-inoculation (DPI). In addition, fecal shedding was prolonged in some animals (e.g., between 6 and 13 DPI in one individual), with up to 10(5.0) PFU/fecal swab detected. West Nile virus was not detected in tissues collected on 10 or 16 DPI, and no histologic lesions attributable to WNV infection were observed. Overall, viremia profiles suggest that raccoons are unlikely to be important WNV amplifying hosts. However, this species may occasionally shed significant quantities of virus in feces. Considering their behavioral ecology, including repeated use of same-site latrines, high levels of fecal shedding could potentially lead to interspecies fecal-oral WNV transmission.

  3. Naturally occurred frame-shift mutations in the tvb receptor gene are responsible for decreased susceptibility to subgroups B, D, and E avian leukosis virus infection in chicken

    Science.gov (United States)

    The group of highly related avian leukosis viruses (ALVs) in chickens were thought to have evolved from a common retroviral ancestor into six subgroups, A to E and J. These ALV subgroups use diverse cellular proteins encoded by four genetic loci in chickens as receptors to gain entry into host cells...

  4. Natural and experimental evidence of viscerotropic infection caused by Leishmania tropica from North Sinai, Egypt.

    Science.gov (United States)

    Doha, Said A; Shehata, Magdi G; Fahmy, Adel R; Samy, Abdallah M

    2014-08-01

    Cutaneous leishmaniasis (CL) is a neglected clinical form that is quite prevalent in Eastern North parts of the country in Sinai Peninsula. Leishmania tropica was identified by previous reports as the causative agent responsible for viscerotropic infections in-patients and experimental animals. Here, we reported the viscerotropic infections from naturally infected rodent Gerbillus pyramidum floweri collected from North-Sinai. Footpad and tail lesions, spleenomegaly, and malformed dark-colored spleen were the characteristic CL symptoms. The spleen of the rodent found positive to amastigote impression smear. ITS-1 DNA was sequenced and revealed 100% identity of the strain in the current study to the other L. tropica sequences identified from the patients with the suspected CL and inhabited the same study area. The current findings confirmed the susceptibility of gerbil to L. tropica, and raise the concerns for the role of rodents as accidental host suffering the infections. The susceptibility of wild and experimental rodents to the same L. tropica strain was also investigated; BALB/c and G. pyramidum were more susceptible to L. tropica (24.33 ± 4.37 and 25 ± 4.58 days post-infection, respectively). Similar viscerotropic pathologies were reported in experimental infection of only golden hamster (≈ 120 days post-infection), and G. p. floweri (≈ 160 days post-infection).

  5. Bovine mastitis caused by Listeria monocytogenes: characteristics of natural and experimental infections.

    Science.gov (United States)

    Bourry, A; Poutrel, B; Rocourt, J

    1995-08-01

    Experimental mastitis induced with a single intramammary injection of Listeria monocytogenes was compared with two naturally occurring cases. Four strains of L. monocytogenes, two of serotype 1/2a and two of serotype 4b were used for the experimental infections and two diametrically opposed quarters of four cows were inoculated with 300 cfu. Bacteriological examination and somatic cell counts of quarter foremilk samples were performed weekly for at least 6 months after challenge. All the inoculated quarters developed chronic subclinical mastitis with occasional clinical episodes. The results were similar to those observed in natural listeria mastitis. Four experimentally infected quarters were treated during lactation (gentamicin and cloxacillin) or at "drying-off" (cloxacillin), or at both times. Only one of four quarters was cured after treatment only at "drying-off". All experimental and naturally infected animals were slaughtered and bacteriological examination was performed on liver, spleen and supramammary, iliac and mesenteric lymph nodes. L. monocytogenes strains were isolated from the supramammary lymph nodes of two experimentally and two naturally infected cows and from an iliac lymph node from one of the naturally infected cows. The epidemiological data were supported by serotyping, lysotyping and DNA macro-restriction analysis. The experimental model of listeria mastitis mimics spontaneous cases and should be useful in further studies of listeria mastitis.

  6. Experimental Infection of the Skin in the Hamster Simulating Human Impetigo IV. Cellular Responses after Streptococcal and Staphylococcal Infections

    Science.gov (United States)

    Dajani, Adnan S.; Wannamaker, Lewis W.

    1972-01-01

    Various cellular responses to skin infections in an experimental animal model were explored. Total leukocyte counts varied after group A streptococcal infections, but a depression was commonly seen after M type 12 impetigo. Staphylococcus aureus infections resulted in moderate leukocytosis. A marked neutrophilia was universal with streptococcal or staphylococcal disease. A positive nitroblue tetrazolium (NBT) response appeared 24 hr after infection, reached a peak in 48 hr, and then declined. This occurred in the absence of extensive cellulitis or bacteremia. An increase in the percentage and absolute number of NBT-positive neutrophils occurred. M type 57 streptococcus produced a more strongly positive NBT test than did M type 12. Cell-free filtrates of a broth culture of M type 57 streptococcus produced NBT responses in hamsters comparable to the responses seen after injection of live organisms. These studies indicate the usefulness of this animal model to study various parameters of the NBT test. PMID:4117885

  7. Experimental infection of meadow voles (Microtus pennsylvanicus) with sheep scrapie

    Science.gov (United States)

    Carlson, CM; Schneider, Jay R.; Pedersen, Janice C.; Heisey, Dennis M.; Johnson, Christopher J.

    2015-01-01

    Meadow voles (Microtus pennsylvanicus) are permissive to chronic wasting disease (CWD) infection, but their susceptibility to other transmissible spongiform encephalopathies (TSEs) is poorly characterized. In this initial study, we intracerebrally challenged 6 meadow voles with 2 isolates of sheep scrapie. Three meadow voles acquired a TSE after the scrapie challenge and an extended incubation period. The glycoform profile of proteinase K-resistant prion protein (PrP(res)) in scrapie-sick voles remained similar to the sheep inocula, but differed from that of voles clinically affected by CWD. Vacuolization patterns and disease-associated prion protein (PrP(Sc)) deposition were generally similar in all scrapie-affected voles, except in the hippocampus, where PrP(Sc) staining varied markedly among the animals. Our results demonstrate that meadow voles can acquire a TSE after intracerebral scrapie challenge and that this species could therefore prove useful for characterizing scrapie isolates.

  8. Genetic Resistance to Scrapie Infection in Experimentally Challenged Goats

    Science.gov (United States)

    Lacroux, Caroline; Perrin-Chauvineau, Cécile; Corbière, Fabien; Aron, Naima; Aguilar-Calvo, Patricia; Torres, Juan Maria; Costes, Pierrette; Brémaud, Isabelle; Lugan, Séverine; Schelcher, François; Barillet, Francis

    2014-01-01

    In goats, several field studies have identified coding mutations of the gene encoding the prion protein (I/M142, N/D146, S/D146, R/Q211, and Q/K222) that are associated with a lower risk of developing classical scrapie. However, the data related to the levels of resistance to transmissible spongiform encephalopathies (TSEs) of these different PRNP gene mutations are still considered insufficient for developing large-scale genetic selection against scrapie in this species. In this study, we inoculated wild-type (WT) PRNP (I142R154R211Q222) goats and homozygous and/or heterozygous I/M142, R/H154, R/Q211, and Q/K222 goats with a goat natural scrapie isolate by either the oral or the intracerebral (i.c.) route. Our results indicate that the I/M142 PRNP polymorphism does not provide substantial resistance to scrapie infection following intracerebral or oral inoculation. They also demonstrate that H154, Q211, and K222 PRNP allele carriers are all resistant to scrapie infection following oral exposure. However, in comparison to WT animals, the H154 and Q211 allele carriers displayed only moderate increases in the incubation period following i.c. challenge. After i.c. challenge, heterozygous K222 and a small proportion of homozygous K222 goats also developed the disease, but with incubation periods that were 4 to 5 times longer than those in WT animals. These results support the contention that the K222 goat prion protein variant provides a strong but not absolutely protective effect against classical scrapie. PMID:24284317

  9. Avian mycoplasmosis update

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    ER Nascimento

    2005-03-01

    Full Text Available Avian mycoplasmas occur in a variety of bird species. The most important mycoplasmas for chickens and turkeys are Mycoplasma gallisepticum (MG, M. synoviae (MS, and M. meleagridis. Besides, M. iowe (MI is an emerging pathogen in turkeys, but of little concern for chickens. Mycoplasmas are bacteria that lack cell wall and belong to the class Mollicutes. Although they have been considered extracellular agents, scientists admit nowadays that some of them are obligatory intracellular microorganisms, whereas all other mycoplasmas are considered facultative intracellular organisms. Their pathogenic mechanism for disease include adherence to host target cells, mediation of apoptosis, innocent bystander damage to host cell due to intimate membrane contact, molecular (antigen mimicry that may lead to tolerance, and mitotic effect for B and/or T lymphocytes, which could lead to suppressed T-cell function and/or production of cytotoxic T cell, besides mycoplasma by-products, such as hydrogen peroxide and superoxide radicals. Moreover, mycoplasma ability to stimulate macrophages, monocytes, T-helper cells and NK cells, results in the production of substances, such as tumor necrosing factor (TNF-alpha, interleukin (IL-1, 2, 6 and interferon (a, b, g. The major clinical signs seen in avian mycoplasmosis are coughing, sneezing, snicks, respiratory rales, ocular and nasal discharge, decreased feed intake and egg production, increased mortality, poor hatchability, and, primarily in turkeys, swelling of the infraorbital sinus(es. Nevertheless, chronic and unapparent infections are most common and more threatening. Mycoplasmas are transmitted horizontally, from bird to bird, and vertically, from dam to offspring through the eggs. Losses attributed to mycoplasmosis, mainly MG and MS infections, result from decreased egg production and egg quality, poor hatchability (high rate of embryonic mortality and culling of day-old birds, poor feed efficiency, increase in

  10. Trypanosoma cruzi-Trypanosoma rangeli co-infection ameliorates negative effects of single trypanosome infections in experimentally infected Rhodnius prolixus.

    Science.gov (United States)

    Peterson, Jennifer K; Graham, Andrea L; Elliott, Ryan J; Dobson, Andrew P; Triana Chávez, Omar

    2016-08-01

    Trypanosoma cruzi, causative agent of Chagas disease, co-infects its triatomine vector with its sister species Trypanosoma rangeli, which shares 60% of its antigens with T. cruzi. Additionally, T. rangeli has been observed to be pathogenic in some of its vector species. Although T. cruzi-T. rangeli co-infections are common, their effect on the vector has rarely been investigated. Therefore, we measured the fitness (survival and reproduction) of triatomine species Rhodnius prolixus infected with just T. cruzi, just T. rangeli, or both T. cruzi and T. rangeli. We found that survival (as estimated by survival probability and hazard ratios) was significantly different between treatments, with the T. cruzi treatment group having lower survival than the co-infected treatment. Reproduction and total fitness estimates in the T. cruzi and T. rangeli treatments were significantly lower than in the co-infected and control groups. The T. cruzi and T. rangeli treatment group fitness estimates were not significantly different from each other. Additionally, co-infected insects appeared to tolerate higher doses of parasites than insects with single-species infections. Our results suggest that T. cruzi-T. rangeli co-infection could ameliorate negative effects of single infections of either parasite on R. prolixus and potentially help it to tolerate higher parasite doses.

  11. Detecting emerging transmissibility of avian influenza virus in human households.

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    Michiel van Boven

    2007-07-01

    Full Text Available Accumulating infections of highly pathogenic H5N1 avian influenza in humans underlines the need to track the ability of these viruses to spread among humans. A human-transmissible avian influenza virus is expected to cause clusters of infections in humans living in close contact. Therefore, epidemiological analysis of infection clusters in human households is of key importance. Infection clusters may arise from transmission events from (i the animal reservoir, (ii humans who were infected by animals (primary human-to-human transmission, or (iii humans who were infected by humans (secondary human-to-human transmission. Here we propose a method of analysing household infection data to detect changes in the transmissibility of avian influenza viruses in humans at an early stage. The method is applied to an outbreak of H7N7 avian influenza virus in The Netherlands that was the cause of more than 30 human-to-human transmission events. The analyses indicate that secondary human-to-human transmission is plausible for the Dutch household infection data. Based on the estimates of the within-household transmission parameters, we evaluate the effectiveness of antiviral prophylaxis, and conclude that it is unlikely that all household infections can be prevented with current antiviral drugs. We discuss the applicability of our method for the detection of emerging human-to-human transmission of avian influenza viruses in particular, and for the analysis of within-household infection data in general.

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

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    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.

  13. Persistent immune responses in late infection and after treatment in experimental Schistosoma bovis infections in goats.

    Science.gov (United States)

    Sörén, K; Monrad, J; Johansen, M V; Lindberg, R

    2009-06-01

    This study explored host immune responses and their possible relationship to the anti-fecundity phenomenon in Schistosoma bovis-infected goats. The design comprised a primary infection with or without treatment at week (wk) 13, and with or without challenge at wk 36. Necropsy was performed at 36 or 52wk. Serum levels of anti-egg IgG, and anti-worm IgG and IgM, were measured by ELISA. In chronic infection, anti-worm antibodies stayed high, reflecting persisting worm burdens, whereas anti-egg IgG remained high despite minimized egg excretion. After treatment, anti-worm IgM and anti-egg IgG were minimized, but anti-worm IgG remained above the values of the uninfected controls. Histopathology showed lowered numbers of perioval granulomas in chronic infection and resolution of liver fibrosis with time, but intestinal lymphoplasmacytic perivasculitis and hepatic eosinophilic infiltrates were maintained at wk 52. Significant splenic plasmacytosis persisted after treatment. The results indicated that persistent immune responses, in chronically infected and in treated goats, may explain sustained worm fecundity depression at challenge infection.

  14. Natural and experimental oral infection of nonhuman primates by bovine spongiform encephalopathy agents.

    Science.gov (United States)

    Bons, N; Mestre-Frances, N; Belli, P; Cathala, F; Gajdusek, D C; Brown, P

    1999-03-30

    Experimental lemurs either were infected orally with the agent of bovine spongiform encephalopathy (BSE) or were maintained as uninfected control animals. Immunohistochemical examination for proteinase-resistant protein (prion protein or PrP) was performed on tissues from two infected but still asymptomatic lemurs, killed 5 months after infection, and from three uninfected control lemurs. Control tissues showed no staining, whereas PrP was detected in the infected animals in tonsil, gastrointestinal tract and associated lymphatic tissues, and spleen. In addition, PrP was detected in ventral and dorsal roots of the cervical spinal cord, and within the spinal cord PrP could be traced in nerve tracts as far as the cerebral cortex. Similar patterns of PrP immunoreactivity were seen in two symptomatic and 18 apparently healthy lemurs in three different French primate centers, all of which had been fed diets supplemented with a beef protein product manufactured by a British company that has since ceased to include beef in its veterinary nutritional products. This study of BSE-infected lemurs early in their incubation period extends previous pathogenesis studies of the distribution of infectivity and PrP in natural and experimental scrapie. The similarity of neuropathology and PrP immunostaining patterns in experimentally infected animals to those observed in both symptomatic and asymptomatic animals in primate centers suggests that BSE contamination of zoo animals may have been more widespread than is generally appreciated.

  15. Cysticercosis in experimentally and naturally infected pigs: parasitological and immunological diagnosis

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    Márcia R.M. da Silva

    2012-04-01

    Full Text Available Our objective was to evaluate the diagnosis of swine cysticercosis by examining "ante mortem" (inspection of the tongue, "post mortem" (inspection and detailed necropsy and ELISA for research in serum of antibodies (Ab-ELISA and antigens (Ag-ELISA. Seven (7 pigs were experimentally infected orally with eggs of Taenia solium and another 10 were naturally infected. In the pigs experimentally infected, inspection of the tongue was negative in all animals, in the routine inspection detailed necropsy and cysticercis were identified in all of them. In pigs with heavy natural infection, inspection of the tongue identified cysticerci in two (20%, while at inspection with necropsy the parasites were identified in large quantities in all animals. In ELISA for antibody search (Ab-ELISA TS-14 recombinant protein was used, and in search for antigen (Ag-ELISA a monoclonal antibody against this protein. In animals experimentally infected, blood was collected weekly for 140 days. The Ab-ELISA identified an increase in titers of antibody to cysticerci 21 days after infection, and at the end of the experimental period six animals (86% were positive to the test. The search for circulating antigens (Ag-ELISA was positive in two pigs 28 to 91 days after infection. All naturally infected pigs were positive for Ag-ELISA and Ab-ELISA. The search for antibodies and antigens by ELISA in serum from 30 pigs of a local farm and without history of cysticercosis was negative. Thus, the use of TS-14 antigen in ELISA test (Ab-ELISA can be useful for the diagnosis of cysticercosis in pigs with low infection.

  16. Immunopathological assessments of human Blastocystis spp. in experimentally infected immunocompetent and immunosuppresed mice.

    Science.gov (United States)

    Abdel-Hafeez, Ekhlas H; Ahmad, Azza K; Abdelgelil, Noha H; Abdellatif, Manal Z M; Kamal, Amany M; Hassanin, Kamel M A; Abdel-Razik, Abdel-Razik H; Abdel-Raheem, Ehab M

    2016-05-01

    Blastocystis spp., one of the most common parasites colonizing the human intestine, is an extracellular, luminal protozoan with controversial pathogenesis. The host's immune response against Blastocystis spp. infection has also not been defined yet. Therefore, this research aimed to assess the potential pathogenicity of this parasite and its ability to modulate the immune response in experimental infected immunocompetent and immunosuppresed mice. These results demonstrated that the infected immunosuppressed mice were more affected than infected immunocompetent mice. Histopathological examination of the small intestine in the infected immunosuppressed mice showed that Blastocystis spp. infiltrated all the layers. Moreover, the epithelia showed exfoliation and inflammatory cell infiltration in submucosa compared to that of the infected immunocompetent mice. As well, examination of the large intestine of the infected immunosuppressed group showed severe goblet cell hyperplasia. Blastocystis spp. infiltrated all the large intestine layers compared to that of the infected immunocompetent group. Furthermore, there was a significant upregulation of the expression of proinflammatory cytokines: interleukin 12 (IL-12) and tumor necrosis factor alpha (TNF-α) in the infected immunosuppressed mice compared to that of the infected immunocompetent ones (p ≤ 0.004 and p ≤ 0.002, respectively). However, the expression of anti-inflammatory cytokines (IL-4 and IL-10) was significantly downregulated in the infected immunosuppressed group compared to that of the infected immunocompetent group one at 10 days postinfection (p ≤ 0.002 and p ≤ 0.001, respectively). The results of this study revealed that Blastocystis spp. affected the production of pro- and anti-inflammatory cytokines in both groups of mice compared to healthy normal (naive) group. Additionally, these data showed that there was a significant upregulation (p ≤ 0.005) of the locally

  17. Praziquantel treatment decreases Schistosoma mansoni genetic diversity in experimental infections.

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    Regina Coeli

    Full Text Available BACKGROUND: Schistosomiasis has a considerable impact on public health in many tropical and subtropical areas. In the new world, schistosomiasis is caused by the digenetic trematode Schistosoma mansoni. Chemotherapy is the main measure for controlling schistosomiasis, and the current drug of choice for treatment is praziquantel (PZQ. Although PZQ is efficient and safe, its repetitive large-scale use in endemic areas may lead to the selection of resistant strains. Isolates less susceptible to PZQ have been found in the field and selected for in the laboratory. The impact of selecting strains with a decreased susceptibility phenotype on disease dynamics and parasite population genetics is not fully understood. This study addresses the impact of PZQ pressure on the genetics of a laboratory population by analyzing frequency variations of polymorphic genetic markers. METHODOLOGY: Infected mice were treated with increasing PZQ doses until the highest dose of 3 × 300 mg/Kg was reached. The effect of PZQ treatment on the parasite population was assessed using five polymorphic microsatellite markers. Parasitological and genetic data were compared with those of the untreated control. After six parasite generations submitted to treatment, it was possible to obtain a S. mansoni population with decreased susceptibility to PZQ. In our experiments we also observed that female worms were more susceptible to PZQ than male worms. CONCLUSIONS: The selective pressure exerted by PZQ led to decreased genetic variability in S. mansoni and increased endogamy. The understanding of how S. mansoni populations respond to successive drug pressure has important implications on the appearance and maintenance of a PZQ resistance phenotype in endemic regions.

  18. Natural and experimental West Nile virus infection in five raptor species.

    Science.gov (United States)

    Nemeth, Nicole; Gould, Daniel; Bowen, Richard; Komar, Nicholas

    2006-01-01

    We studied the effects of natural and/or experimental infections of West Nile virus (WNV) in five raptor species from July 2002 to March 2004, including American kestrels (Falco sparverius), golden eagles (Aquila chrysaetos), red-tailed hawks (Buteo jamaicensis), barn owls (Tyto alba), and great horned owls (Bubo virginianus). Birds were infected per mosquito bite, per os, or percutaneously by needle. Many experimentally infected birds developed mosquito-infectious levels of viremia (>10(5) WNV plaque forming units per ml serum) within 5 days postinoculation (DPI), and/ or shed virus per os or per cloaca. Infection of organs 15-27 days postinoculation was infrequently detected by virus isolation from spleen, kidney, skin, heart, brain, and eye in convalescent birds. Histopathologic findings varied among species and by method of infection. The most common histopathologic lesions were subacute myocarditis and encephalitis. Several birds had a more acute, severe disease condition represented by arteritis and associated with tissue degeneration and necrosis. This study demonstrates that raptor species vary in their response to WNV infection and that several modes of exposure (e.g., oral) may result in infection. Wildlife managers should recognize that, although many WNV infections are sublethal to raptors, subacute lesions could potentially reduce viability of populations. We recommend that raptor handlers consider raptors as a potential source of WNV contamination due to oral and cloacal shedding.

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

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    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.

  20. Experimental Hendra virus infection of dogs: virus replication, shedding and potential for transmission.

    Science.gov (United States)

    Middleton, D J; Riddell, S; Klein, R; Arkinstall, R; Haining, J; Frazer, L; Mottley, C; Evans, R; Johnson, D; Pallister, J

    2017-01-01

    Characterisation of experimental Hendra virus (HeV) infection in dogs and assessment of associated transmission risk. Beagle dogs were exposed oronasally to Hendra virus/Australia/Horse/2008/Redlands or to blood collected from HeV-infected ferrets. Ferrets were exposed to oral fluids collected from dogs after canine exposure to HeV. Observations made and samples tested post-exposure were used to assess the clinical course and replication sites of HeV in dogs, the infectivity for ferrets of canine oral fluids and features of HeV infection in dogs following contact with infective blood. Dogs were reliably infected with HeV and were generally asymptomatic. HeV was re-isolated from the oral cavity and virus clearance was associated with development of virus neutralising antibody. Major sites of HeV replication in dogs were the tonsils, lower respiratory tract and associated lymph nodes. Virus replication was documented in canine kidney and spleen, confirming a viraemic phase for canine HeV infection and suggesting that urine may be a source of infectious virus. Infection was transmitted to ferrets via canine oral secretions, with copy numbers for the HeV N gene in canine oral swabs comparable to those reported for nasal swabs of experimentally infected horses. HeV is not highly pathogenic for dogs, but their oral secretions pose a potential transmission risk to people. The time-window for transmission risk is circumscribed and corresponds to the period of acute infection before establishment of an adaptive immune response. The likelihood of central nervous system involvement in canine HeV infection is unclear, as is any long-term consequence. © 2017 Australian Veterinary Association.

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

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    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.

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

    DEFF Research Database (Denmark)

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

    2006-01-01

    The outcome of experimental intestinal infections with enterotoxigenic Escherichia coli (ETEC) is dependent on several factors. An important factor is adhesion of the challenge strain to the intestinal mucosa. The test for susceptibility towards ETEC adhesion has so far been made by an intestinal...... 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......-gastric intubated with 10(9) CFU of ETEC O149:F4ac and 23 age-matched piglets, both susceptible and resistant, were used as non-infected controls. Of susceptible piglets, challenged with ETEC 0149:F4ac, 74% had ETEC O149:F4ac-associated diarrhoea first day after first challenge, which were significantly higher...

  3. Eimeria stiedai: Metabolism of lipids, proteins and glucose in experimentally infected rabbits, Oryctolagus cuniculus

    OpenAIRE

    Freitas, Fagner L. C.; Yamamoto, Beatriz L.; Freitas, Wagner L. C; Almeida, Katyane S; Machado, Rosangela Z. [UNESP; Machado, Célio R. [UNESP

    2010-01-01

    Rabbits were experimentally infected with sporulated Eimeria stiedai oocysts. A total of 50 white adult rabbits, New Zealand race, were distributed into two groups: Group A was infected with 1x10 4 sporulated Eimeria stiedai oocysts, while group B was inoculated with distilled water as a control. The animals generally displayed increased levels of total protein, globulin, total cholesterol, LDL-c and triacylglycerols; however, total levels of liver lipids and HDL-c decreased, and plasma gluco...

  4. Experimental Infection of Rabbits with Rabbit and Genotypes 1 and 4 Hepatitis E Viruses

    OpenAIRE

    Ma, H. X.; Zheng, L.; Liu, Y. B.; Zhao, C. Y.; Harrison, T. J.; Ma, Y. Y.; Sun, S. H.; Zhang, J. G.; Wang, Y. C.

    2010-01-01

    BACKGROUND: A recent study provided evidence that farmed rabbits in China harbor a novel hepatitis E virus (HEV) genotype. Although the rabbit HEV isolate had 77-79% nucleotide identity to the mammalian HEV genotypes 1 to 4, their genomic organization is very similar. Since rabbits are used widely experimentally, including as models of infection, we investigated whether they constitute an appropriate animal model for human HEV infection. METHODS: Forty-two SPF rabbits were divided randomly in...

  5. 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 ... juice. Commercially available cranberry juice cocktail also significantly reduced (P juice (P juice, were tested...... in combination and individually. The four organic acids also decreased bacterial levels in the bladder when administered together (P plus citric acid (P plus quinic acid (P

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

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    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.

  7. Experimental infection of dogs with Leishmania and saliva as a model to study Canine Visceral Leishmaniasis.

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    Dirceu Joaquim Costa

    Full Text Available BACKGROUND: Canine Visceral Leishmaniasis (CVL is a zoonotic disease caused by Leishmania infantum, transmitted by the bite of Lutzomyia longipalpis sand flies. Dogs are the main domestic reservoir of the parasite. The establishment of an experimental model that partially reproduces natural infection in dogs is very important to test vaccine candidates, mainly regarding those that use salivary proteins from the vector and new therapeutical approaches. METHODOLOGY/PRINCIPAL FINDINGS: In this report, we describe an experimental infection in dogs, using intradermal injection of Leishmania infantum plus salivary gland homogenate (SGH of Lutzomyia longipalpis. Thirty-five dogs were infected with 1×10(7 parasites combined with five pairs of Lutzomyia longipalpis salivary glands and followed for 450 days after infection and clinical, immunological and parasitological parameters were evaluated. Two hundred and ten days after infection we observed that 31,4% of dogs did not display detectable levels of anti-Leishmania antibodies but all presented different numbers of parasites in the lymph nodes. Animals with a positive xenodiagnosis had at least 3,35×10(5 parasites in their lymph nodes. An increase of IFN-γ and IL-10 levels was detected during infection. Twenty two percent of dogs developed symptoms of CVL during infection. CONCLUSION: The infection model described here shows some degree of similarity when compared with naturally infected dogs opening new perspectives for the study of CVL using an experimental model that employs the combination of parasites and sand fly saliva both present during natural transmission.

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

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    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.

  9. 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.

  10. 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.

  11. Development of an experimental model of infected bone void in the ulna of rabbits

    Science.gov (United States)

    Lemos Azi, Matheus; Kfuri Junior, Mauricio; Martinez, Roberto; Salata, Luis Antonio; Paccola, Cleber Antonio Jansen

    2012-01-01

    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 5x108 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. PMID:24453593

  12. Persistence of viral RNA in the brain of experimentally infected mice with coxsackievirus B5

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    Sobotova Z.

    2011-04-01

    Full Text Available The aim of our study was to follow the persistence of viral RNA in selected organs of experimentally infected with coxsackievirus (CV B5 strains from different sources such as a patient’s sample, an environmental sample and a prototype virus strain. Methods . CD-1 mice were infected with CVB5 strain Faulkner the prototype, CVB5 – isolate from treated sewage waste and isolate from patient’s stool sample both identified as CVB5. The viral RNA was detected by RT-PCR using enterovirus primers specific for the non-coding 5' region. Results . We observed presence of RNA in the brain and heart of mice infected with isolate from patient’s stool at day 45 post infection (p. i.. Conclusion. We conclude that CVB5 persists in the brain and heart after oral infection of CD1 mice. The relevance of viral persistence maybe related viral origin and the genetics

  13. Comparison of detection methods for Toxoplasma gondii in naturally and experimentally infected swine.

    Science.gov (United States)

    Hill, Dolores E; Chirukandoth, Sreekumar; Dubey, J P; Lunney, Joan K; Gamble, H Ray

    2006-10-10

    Results from recent serological surveys and epidemiological studies show that pigs raised in a variety of management systems can be carriers of the tissue cyst stage of Toxoplasma gondi. This parasite can be transmitted to humans through the consumption of improperly prepared pork, making detection and removal of infected swine carcasses from the food chain an important food safety issue. Several methods are available for detection of T. gondii infected swine, including serological assays, polymerase chain reaction, and animal bioassays. The aim of the present study was to compare the detection sensitivities of six of these commonly used methods for detection of T. gondii infection in tissues from naturally and experimentally infected pigs. The results indicate that a serum-based ELISA is the most sensitive method, of those tested, for detection of T. gondii infected swine.

  14. Clinical pathology of experimental Schistosoma curassoni infections in sheep and goats.

    Science.gov (United States)

    Vercruysse, J; Fransen, J; Southgate, V R; Rollinson, D; Majeleine, W

    1988-05-01

    The clinical pathology of Schistosoma curassoni infection in sheep and goats was studied for 22 weeks following experimental infection with 7000 and 4000 cercariae, respectively. Excretion of eggs began at week 7 after infection: in goats the numbers increased to 30 to 50 eggs per gram faeces (epg) at weeks 8 to 18, followed by a reduction. In a pregnant goat, epg values increased markedly before and after parturition. The mean faecal egg counts in sheep were lower than in goats, increasing to a maximum level of 30 epg at weeks 16 and 17 after infection. Infected sheep maintained growth rates roughly comparable with controls, whereas infected goats failed to gain as much weight as the controls. Infected goats and sheep produced eosinophil counts of about 3 x 10(3) mm-3, five and eight weeks after infection, respectively. Sheep developed a progressive anaemia from week 11 after infection, in goats blood values remained within normal limits. Differences in serum protein concentration were observed between infected and uninfected goats about nine weeks after infection, but not in sheep. Increased total protein values, hyperglobulinaemia and lowered albumin to globulin ratios were features of infected goats. Serum glutamate oxaloacetate transaminase, glutamate pyruvate transaminase, gamma-glutamyl transferase, total lactate dehydrogenase and bilirubin were not significantly changed. The mean recovery in sheep was 608 worms, in goats 428 worms, but the total tissue egg counts were higher in the latter. Of the total eggs deposited in the goats 92 per cent were found in the liver with 51.5 per cent in the ovine liver. The histopathological changes were studied.

  15. Diurnal fluctuations in nematode egg excretion in naturally and in experimentally infected chickens.

    Science.gov (United States)

    Wongrak, Kalyakorn; Gauly, Matthias; Daş, Gürbüz

    2015-03-15

    We investigated whether nematode egg excretion through feces of naturally or experimentally infected chickens follow certain patterns within a day, which may allow determining the most appropriate sampling time for the highest parasite egg concentration. Feces samples (n=864) from chickens (n=36) with naturally occurring mixed nematode infections (trials N1, N2) or with an experimental Ascaridia galli infection (E) were collected quantitatively every 4h for four consecutive days. Number of eggs per gram of feces (EPG) was determined, and accumulative egg output (AEO) at each sampling time as well as total number of eggs excreted within 24h (eggs per day, EPD) were then estimated. At the end of the collection period, the hens were necropsied and their worm burdens determined. Naturally infected hens harbored Heterakis gallinarum (100%), Capillaria spp. (95.7%) and A. galli (91.3%). The experimental A. galli infection produced patent infections in all the birds. In general, both fecal egg concentration (EPG) and the amount of feces increased (P0.05) between effects of sampling hours and days on EPG and AEO, suggesting the existence of repeatable diurnal fluctuations within each day. Although an association between climatic parameters (e.g., ambient temperature and relative humidity) and the nematode egg excretion was quantified, a causal relationship could not be demonstrated. We conclude that nematode egg excretion through chicken feces in both natural and experimental infections shows repeatable diurnal fluctuations, which may indicate adaptive strategies by nematodes and eventually favor parasite spread. Since analytic sensitivity of fecal egg counts suffers from low egg concentrations in feces, samples taken during the daytime have a higher diagnostic value. Copyright © 2015 Elsevier B.V. All rights reserved.

  16. The avian influenza H9N2 at avian-human interface: A possible risk for the future pandemics.

    Science.gov (United States)

    RahimiRad, Shaghayegh; Alizadeh, Ali; Alizadeh, Effat; Hosseini, Seyyed Masoud

    2016-01-01

    The avian influenza subtype H9N2 is considered a low pathogenic virus which is endemic in domestic poultry of a majority of Asian countries. Many reports of seropositivity in occupationally poultry-exposed workers and a number of confirmed human infections with an H9N2 subtype of avian influenza have been documented up to now. Recently, the human infections with both H7N9 and H10N8 viruses highlighted that H9N2 has a great potential for taking a part in the emergence of new human-infecting viruses. This review aimed at discussing the great potential of H9N2 virus which is circulating at avian-human interface, for cross-species transmission, contribution in the production of new reassortants and emergence of new pandemic subtypes. An intensified surveillance is needed for controlling the future risks which would be created by H9N2 circulation at avian-human interfaces.

  17. Dynamic distribution and tissue tropism of classical swine fever virus in experimentally infected pigs

    Science.gov (United States)

    2011-01-01

    Background Classical swine fever (CSF), caused by the Classical swine fever virus (CSFV), is an Office International des Epizooties (OIE) notifiable disease. However, we are far from fully understand the distribution, tissue tropism, pathogenesis, replication and excretion of CSFV in pigs. In this report, we investigated the dynamic distribution and tissue tropism of the virus in internal organs of the experimentally infected pigs using real-time RT-PCR and immunohistochemistry (IHC). Results A relative quantification real-time PCR was established and used to detect the virus load in internal organs of the experimentally infected pigs. The study revealed that the virus was detected in all 21 of the internal organs and blood collected from pigs at day 1 to day 8 post infections, and had an increasing virus load from day 1 to day 8 post infections. However, there was irregular distribution virus load in most internal organs over the first 2 days post infection. Blood, lymphoid tissue, pancreas and ileum usually contain the highest viral loads, while heart, duodenum and brain show relatively low viral loads. Conclusions All the data suggest that CSFV had an increasing virus load from day 1 to day 8 post infections in experimentally infected pigs detected by real-time RT-PCR, which was in consistent with the result of the IHC staining. The data also show that CSFV was likely to reproduce in blood, lymphoid tissue, pancreas and the ileum, while unlikely to replicate in the heart, duodenum and brain. The results provide a foundation for further clarification of the pathogenic mechanism of CSFV in internal organs, and indicate that blood, lymphoid tissue, pancreas and ileum may be preferred sites of acute infection. PMID:21535885

  18. Inferring biomarkers for Mycobacterium avium subsp. paratuberculosis infection and disease progression in cattle using experimental data

    Science.gov (United States)

    Magombedze, Gesham; Shiri, Tinevimbo; Eda, Shigetoshi; Stabel, Judy R.

    2017-03-01

    Available diagnostic assays for Mycobacterium avium subsp. paratuberculosis (MAP) have poor sensitivities and cannot detect early stages of infection, therefore, there is need to find new diagnostic markers for early infection detection and disease stages. We analyzed longitudinal IFN-γ, ELISA-antibody and fecal shedding experimental sensitivity scores for MAP infection detection and disease progression. We used both statistical methods and dynamic mathematical models to (i) evaluate the empirical assays (ii) infer and explain biological mechanisms that affect the time evolution of the biomarkers, and (iii) predict disease stages of 57 animals that were naturally infected with MAP. This analysis confirms that the fecal test is the best marker for disease progression and illustrates that Th1/Th2 (IFN-γ/ELISA antibodies) assays are important for infection detection, but cannot reliably predict persistent infections. Our results show that the theoretical simulated macrophage-based assay is a potential good diagnostic marker for MAP persistent infections and predictor of disease specific stages. We therefore recommend specifically designed experiments to test the use of a based assay in the diagnosis of MAP infections.

  19. 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.

  20. Diffferential innate responses of chickens and ducks to low pathogenic avian influenza virus

    NARCIS (Netherlands)

    Cornelissen, J.B.W.J.; Post, J.; Peeters, B.P.H.; Vervelde, L.; Rebel, J.M.J.

    2012-01-01

    Ducks and chickens are hosts of avian influenza virus, each with distinctive responses to infection. To understand these differences, we characterized the innate immune response to low pathogenicity avian influenza virus H7N1 infection in chickens and ducks. Viral RNA was detected in the lungs of

  1. 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.

  2. Experimental porcine rubulavirus (La Piedad-Michoacan virus) infection in pregnant gilts.

    Science.gov (United States)

    Hernández-Jáuregui, P; Ramírez Mendoza, H; Mercado García, C; Moreno-López, J; Kennedy, S

    2004-01-01

    Porcine rubulavirus (La Piedad-Michoacan virus) (PoRV-LPMV) is a member of the Paramyxoviridae family that causes encephalitis in young piglets and infertility in adult sows and boars. Infertility in sows naturally infected by PoRV-LPMV is characterized by an increased number of returns to oestrus, stillbirths and mummified fetuses. In this study, nine seronegative gilts were inoculated intranasally with the PAC-3 strain of PoRV-LPMV at week 6 or 10 of gestation. These animals were then killed at weeks 8 or 15 of gestation (seven gilts) or after natural parturition (two gilts). Four control gilts were mock-infected at gestation week 6 or 10 and killed between 2 and 4 weeks later. Gross lesions of focal congestion and haemorrhage were seen in the placenta and endometrium of one gilt infected at gestation week 6 and one infected at gestation week 10. PoRV-LPMV was isolated, at 2-6 weeks post-inoculation (pi), from lung, tonsils, ovary, placenta, uterus and lymph nodes of three of the gilts infected at gestation week 6 and at 2-3 weeks pi from lung, tonsil and ovary of two gilts infected at gestation week 10. Many of the fetuses of eight infected gilts were smaller than normal and had dermal ecchymoses. Dehydrated or mummified fetuses were present in six of the infected gilts but not in any control animal. PoRV-LPMV was isolated from brain, lung and liver of fetuses from two gilts infected at gestation week 6, and from two infected at gestation week 10. These results indicate that, after experimental infection, PoRV can replicate in tissues of seronegative pregnant gilts, cross the placenta, and cause fetal death and mummification.

  3. 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...

  4. Schmallenberg virus detection in bovine semen after experimental infection of bulls.

    NARCIS (Netherlands)

    Poel, van der W.H.M.; Parlevliet, J.M.; Verstraten, E.R.A.M.; Kooi, E.A.; Hakze-van der Honing, van der R.W.; Stockhofe-Zurwieden, N.

    2014-01-01

    To study Schmallenberg virus (SBV) excretion in bovine semen after experimental infection, two bulls were inoculated subcutaneously with a SBV isolate (1 ml Vero cell culture 106 TCID50). After inoculation (at day 0), semen was collected daily from both animals for 21 days and samples were tested

  5. Pathology of Experimental Encephalitozoon cuniculi Infection in Immunocompetent and Immunosuppressed Mice in Iraq

    Directory of Open Access Journals (Sweden)

    Hafidh I. Al-Sadi

    2014-01-01

    Full Text Available This study was performed to evaluate pathology of experimental Encephalitozoon cuniculi (Iraqi isolate infection in normal and immunosuppressed mice. Pathological changes were not seen in negative control mice while secondary bacterial infections were noted in the lungs, kidneys, and heart of mice given dexamethasone. Typical E. cuniculi infection lesions were found in brain, livers, lungs, and kidneys of mice given 107  E. cuniculi spores/mouse orally. These lesions were in the form of nonsuppurative meningoencephalitis with vasculitis in brain, interstitial inflammation with infiltration of both lymphocytes and plasma cells in lung tissue, and nonsuppurative interstitial (focal and diffuse nephritis, presence of vacuole containing mature and immature spores in enterocytes within the tips of villi, and lymphoiod hyperplasia of the white pulp and vasculitis of the intratrabecular vessels. Mice that were given 107  E. cuniculi spores/mouse orally showed lesions similar to those observed in the previous group (vasculitis and granulomas but the lesions were more severe and widespread. In conclusion, this is the first report of experimental E. cuniculi infection induced by E. cuniculi isolated from a naturally infected rabbit in Iraq and that infection became more severe and widespread upon the administration of dexaethasone.

  6. 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.$?

  7. 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.

  8. 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.

  9. Efficacy of toltrazuril against experimental infections with Eimeria labbeana and E. columbarum in racing pigeons.

    Science.gov (United States)

    Van Reeth, K; Vercruysse, J

    1993-01-01

    The efficacy of toltrazuril against heavy experimental Eimeria labbeana and E. columbarum infections in racing pigeons was investigated. Pigeons were treated with toltrazuril at a dose of 20 mg/kg body weight before, during, and after the pre-patent period. In pigeons treated during pre-patency (1-5 days postinoculation [PI]), a 99.9% reduction in oocyst output was observed at day 7 PI. Treatment during patency (6-7 days PI) resulted in an interruption of oocyst shedding within 3 to 4 days. Pigeons treated with toltrazuril up to 14 days before the experimental infection showed on average a reduction of more than 97% in the number of oocysts in individual fecal samples. Finally, at reinfection, the immune response of pigeons previously treated during pre-patency was not altered compared with the response of infected unmedicated controls.

  10. Avian bornaviruses are widely distributed in canary birds (Serinus canaria f. domestica).

    Science.gov (United States)

    Rubbenstroth, Dennis; Rinder, Monika; Stein, Malte; Höper, Dirk; Kaspers, Bernd; Brosinski, Katrin; Horie, Masayuki; Schmidt, Volker; Legler, Marko; Korbel, Rüdiger; Staeheli, Peter

    2013-08-30

    Avian bornavirus (ABV) was identified in 2008 as the causative agent of proventricular dilatation disease (PDD) in psittacine birds. In addition, ABV variants were detected in wild waterfowl and in a canary bird. PDD-like diseases were also reported in various other avian species, but it remains unknown whether ABV is involved. In this study we detected ABV in 12 of 30 tested canary bird flocks (40%), indicating a wide distribution of ABV in captive canary birds in Germany. Sequence analysis identified several distinct ABV genotypes which differ markedly from the genotypes present in psittacine birds. Some canaries naturally infected with ABV exhibited gastrointestinal and neurological symptoms which resembled PDD in psittacines, while others did not show signs of disease. Canaries experimentally inoculated with ABV developed infections of the brain and various other organs. The experimentally infected canaries transmitted the virus to sentinel birds kept in the same aviary, but did not show any clinical signs during a five month observation period. Embryonated eggs originating from ABV-infected hens contained ABV-specific RNA, but virus could not be re-isolated from embryonic tissue. These results indicate that ABV is widely distributed in canary birds and due to its association to clinical signs should be considered as a potential pathogen of this species. Copyright © 2013. Published by Elsevier B.V.

  11. 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

    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...... 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...

  12. Induced expression of the antimicrobial peptide melittin inhibits experimental infection by Mycoplasma gallisepticum in chickens.

    Science.gov (United States)

    Lazarev, Vassili N; Stipkovits, Laszlo; Biro, Judit; Miklodi, Dora; Shkarupeta, Marina M; Titova, Galina A; Akopian, Tatiana A; Govorun, Vadim M

    2004-05-01

    The in vivo action of the antimicrobial peptide melittin, expressed from a recombinant plasmid vector, on chickens experimentally infected with Mycoplasma gallisepticum was studied. The plasmid vector pBI/mel2/rtTA includes the melittin gene under the control of an inducible tetracycline-dependent human cytomegalovirus promoter and the gene coding for the trans-activation protein rtTA. Aerosol administration of the vector, followed by infecting the chickens with M. gallisepticum 1226, is shown to inhibit development of infection. The inhibitory action was confirmed by a complex of clinical, pathomorphological, histological and serological studies, and also by comparing the M. gallisepticum reisolation frequency from the respiratory tract and internal organs. The data suggest that plasmid vectors expressing genes of antimicrobial peptides can be considered as potential agents for the prevention and treatment of mycoplasma infections in poultry farming.

  13. Lactation curve and milk quality of goats experimentally infected with Trypanosoma vivax.

    Science.gov (United States)

    Lopes, Francisco Canindé; de Paiva, Kaliane Alessandra Rodrigues; Coelho, Wesley Adson Costa; Nunes, Francisco Vítor Aires; da Silva, Jardel Bezerra; de Gouveia Mendes da Escóssia Pinheiro, Carolina; de Macêdo Praça, Layanne; Silva, Jean Berg Alves; Alves Freitas, Carlos Iberê; Batista, Jael Soares

    2016-08-01

    The present study aimed to evaluate the effects of Trypanosoma vivax infection on the shape of the lactation curve and the milk quality of dairy goats experimentally infected with T. vivax. In total, twenty Saanen goats, aged 26-30 months and the same number of calving (two calvings), were divided into two experimental groups: an infected group, consisting of ten goats intravenously infected with 0.5 ml of blood containing approximately 1.25 × 10(5) trypomastigotes of T. vivax and ten uninfected animals as the control group. Clinical tests and hematocrit, parasitemia, and serum biochemistry evaluations were performed on all of the goats. Milk production was measured daily for 152 days by hand milking the goats and weighing the milk. Every seven days, physiochemical analyses were performed to evaluate the milk. Wood's nonlinear model was used to analyze the lactation curve parameters. The infected goats had high levels of parasitemia and hyperthermia, significantly reduced hematocrit, serum total protein, albumin, and glucose levels and increased cholesterol and urea concentrations. Wood's model indicated that the milk production of goats in the infected group declined sharply over a short period of time and produced a flattened yield curve and significant difference (P physico-chemical properties of the milk, including the fat content, defatted dry extracts (DDE) and protein content, decreased significantly (P < 0.05) in the goats in the infected group compared with those in the control group. The T. vivax-infected goats showed reduction in milk production, persistence of lactation, and fat levels, the defatted dry extract (DDE) content, and protein, changing the quality of milk. Copyright © 2016 Elsevier Inc. All rights reserved.

  14. 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.

  15. 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...... 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...... polymorphonuclear) cells. F. psychrophilus infection in rainbow trout fry involves the monocyte-macrophage system extensively, and the concurrent localization of bacteria in the skin ulcers and retinal inflammation points to the probable involvement of the bacterium in the development of the lesions which...

  16. 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.

  17. 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.

  18. An enzyme-linked immunosorbent assay for detection of avian influenza virus subtypes H5 and H7 antibodies

    DEFF Research Database (Denmark)

    Jensen, Trine Hammer; Ajjouri, Gitte; Handberg, Kurt

    2013-01-01

    of this method. However, enzyme-linked immunosorbent assays (ELISAs) are being explored as an alternative test method.H5 and H7 specific monoclonal antibodies were experimentally raised and used in the development of inhibition ELISAs for detection of serological response specifically directed against AIV...... during experimental infection than the HI test did. The reproducibility of the ELISA’s performed at different times was high with Pearson correlation coefficients of 0.96-0.98. CONCLUSIONS: The ELISAs are a potential alternative to the HI test for screening of large amounts of avian sera, although only......BACKGROUND: Avian influenza virus (AIV) subtypes H5 and H7 attracts particular attention because of the risk of their potential pathogenicity in poultry. The haemagglutination inhibition (HI) test is widely used as subtype specific test for serological diagnostics despite the laborious nature...

  19. Evaluating the role of wild songbirds or rodents in spreading avian influenza virus across an agricultural landscape

    National Research Council Canada - National Science Library

    Marks, David R; Azeem, Shahan; Sato, Yuko; Adelman, James S; Lundy, Coady W; Blanchong, Julie A; Guo, Baoqing; Houston, Derek D; Yoon, Kyoung-Jin; Gauger, Phillip C

    2017-01-01

    Background Avian influenza virus (AIV) infections occur naturally in wild bird populations and can cross the wildlife-domestic animal interface, often with devastating impacts on commercial poultry...

  20. Faktor Risiko Terkait Manajemen Kesehatan Unggas terhadap Infeksi Virus Flu Burung di Tempat Penampungan Ayam (THE RISK FACTOR OF POULTRY HEALTH MANAGEMENT TO THE INFECTION OF AVIAN INFLUENZA VIRUS IN POULTRY COLLECTING FACILITIES

    Directory of Open Access Journals (Sweden)

    Chaerul Basri

    2013-09-01

    Full Text Available The aim of the study was to determine the association between the implementation of poultryhealth management and the spread of avian influenza virus in Poultry Collecting Facilities (PCFs.  Thestudy was performed by maintaining 7-8 sentinel chickens in 39 PCFs in Jakarta for three months.  Thevariables evaluated for poultry health management were health certificate, health inspection, healthinspector, health inspection method, and handling of sick and dead birds. Data on the variables werecollected by interview with supervisor of PCFs.  The AIV infection were detected by rt-PCR from the cloacaland tracheal swab of the dead birds with.  The results showed that the methodes of handling of sick birdswere significantly associated with infection of AIV (RR=2,00 ; 95% CI  = 1,31-3,05.  The other variables didnot show significance association.  The risk of AIV infection was twice higher  the sick keeping side birdsalive, or by separating, or treating the birds in the same cage than by slaughtering them. Poultry healthmanagement in PCFs need to be improved in order to prevent and control the spreading of AIV in Indonesia.

  1. Therapeutic and Safety Evaluation of Combined Aqueous Extracts of Azadirachta indica and Khaya senegalensis in Chickens Experimentally Infected with Eimeria Oocysts

    Directory of Open Access Journals (Sweden)

    J. G. Gotep

    2016-01-01

    Full Text Available Coccidiosis is a disease of economic importance in poultry causing morbidity and mortality. Reports show that Azadirachta indica and Khaya senegalensis have been used individually in the treatment of avian coccidiosis. We thus investigated the efficacy and safety of the combined aqueous extracts of these plants for the treatment of experimentally induced coccidiosis in broiler chickens using oocyst count, oxidative stress biomarkers, serum biochemistry, histology, and haematological parameters. The phytochemical screening revealed the presence of tannins, saponins, cardiac glycosides, and steroids in both extracts. In addition, alkaloids and flavonoids were present in Azadirachta indica. There was significant (p<0.05 dose dependent decrease in oocyst count across the treatment groups with 400 mg/kg of the combined extract being the most efficacious dose. Immunomodulatory and erythropoietic activity was observed. There were decreased intestinal lesions and enhanced antioxidant activity across the treatment groups compared to the negative control. Administration of the combined extract did not cause damage to the liver as ALT, AST, and ALP levels were significantly reduced in the uninfected chickens treated with the extracts compared to control suggesting safety at the doses used. The combined aqueous extracts of K. senegalensis stem bark and Azadirachta indica leaves were ameliorative in chickens infected with coccidiosis.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1979-02-01

    The capability of radionuclide imaging to detect experimental aortic valve infective endocarditis was assessed with indium-111 (/sup 111/In)-labeled blood cells. Sequential cardiac imaging and tissue distribution studies were obtained in 17 rabbits with infective endocarditis after administration of /sup 111/-In-platelets and in five after /sup 111/In-polymorphonuclear leukocytes. Forty-eight to 72 hours after platelet administration, in vivo imaging demonstrated abnormal /sup 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. /sup 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, /sup 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 /sup 111/In platelet scintigraphs nor abnormal cardiac tissue uptake. Likewise, noncellular /sup 111/In was not concentrated to any significant extent in three animals with infective endocarditis.This study demonstrates that /sup 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.

  3. Imaging experimental infective endocarditis with indium-111-labeled blood cellular components. [Rabbits, aortic valve

    Energy Technology Data Exchange (ETDEWEB)

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

    1979-02-01

    The capability of radionuclide imaging to detect experimental aortic valve infective endocarditis was assessed with indium-111 (/sup 111/In)-labeled blood cells. Sequential cardiac imaging and tissue distribution studies were obtained in 17 rabbits with infective endocarditis after administration of /sup 111/In-platelets and in five after /sup 111/In-polymorphonuclear leukocytes. Forty-eight to 72 hours after platelet administration, in vivo imaging demonstrated abnormal /sup 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. /sup 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, /sup 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 /sup 111/In-platelet scintigraphs nor abnormal cardiac tissue uptake. Likewise, noncellular /sup 111/In was not concentrated to any significant extent in three animals with infective endocarditis. This study demonstrates that /sup 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.

  4. Avian Fact Sheet

    Energy Technology Data Exchange (ETDEWEB)

    NWCC Wildlife Work Group

    2004-12-01

    OAK-B135 After conducting four national research meetings, producing a document guiding research: Metrics and Methods for Determining or Monitoring Potential Impacts on Birds at Existing and Proposed Wind Energy Sites, 1999, and another paper, Avian Collisions with Wind Turbines: A Summary of Existing Studies and Comparisons to Other Sources of Avian Collision Mortality in the United States, 2001, the subcommittee recognized a need to summarize in a short fact sheet what is known about avian-wind interaction and what questions remain. This fact sheet attempts to summarize in lay terms the result of extensive discussion about avian-wind interaction on land. This fact sheet does not address research conducted on offshore development. This fact sheet is not intended as a conclusion on the subject; rather, it is a summary as of Fall/Winter 2002.

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

    Directory of Open Access Journals (Sweden)

    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

  6. Schmallenberg virus infection in South American camelids: Field and experimental investigations.

    Science.gov (United States)

    Schulz, Claudia; Beer, Martin; Hoffmann, Bernd

    2015-11-18

    During the first epizootic wave of the novel, teratogenic Schmallenberg virus (SBV, Orthobunyavirus) in ruminants in Northern Europe, serological evidence of a previous SBV-infection demonstrated that South American camelids (SAC) are also susceptible to SBV. However, their potential role in SBV spread remains unknown. To investigate the prevalence and course of SBV-infection in SAC, a German field study and an animal trial with three llamas and three alpacas were conducted. From September 2012 to December 2013, 313 of 502 SAC (62.35%) were found SBV seropositive, but negative for SBV-RNA. The estimated between-district (94.23% of 52) and median within-district (71.43%) and herd (73.13%) SBV seroprevalence in German SAC was similar to the seroprevalence reported in cattle herds and sheep flocks at the time. An age of >1 year was found a statistically significant risk factor for SBV-infection, which could be explained by the spatio-temporal spread of SBV in Germany during the study period. No clinical signs or an increase of abortion and congenital malformation associated with SBV-infection in SAC were reported by the study participants. Similar to SBV-infected ruminants, SBV-RNAemia in experimentally SBV-infected SAC was detected for a short time between days 3 and 7 after infection (dpi), and seroconversion occurred between 9 and 21 dpi. Despite the similar virological and serological results, the lack of clinical signs and congenital malformation associated with SBV-infection suggests that SBV causes subclinical infection in SAC. However, their role as reservoirs in the spread of SBV has to be further investigated. Copyright © 2015 Elsevier B.V. All rights reserved.

  7. Persistence of viral RNA in the brain of experimentally infected mice with coxsackievirus B5

    OpenAIRE

    Sobotova Z.; Marosova L.; Badurova M.; Sojka M.; Borsanyiova M.; Stipalova D.; Bopegamage S.

    2011-01-01

    The aim of our study was to follow the persistence of viral RNA in selected organs of experimentally infected with coxsackievirus (CV) B5 strains from different sources such as a patient’s sample, an environmental sample and a prototype virus strain. Methods . CD-1 mice were infected with CVB5 strain Faulkner the prototype, CVB5 – isolate from treated sewage waste and isolate from patient’s stool sample both identified as CVB5. The viral RNA was detected by RT-PCR using enterovirus primers sp...

  8. Experimental infections with rifampicin-resistant Clostridium perfringens strains in broiler chickens using isolator facilities

    DEFF Research Database (Denmark)

    Pedersen, Karl; Bjerrum, Lotte; Nauerby, Birgitte

    2003-01-01

    Experimental infection studies were carried out on the ability of three Clostridium perfringens type A rifampicin-resistant strains to colonize the intestinal tract of broiler chickens kept in isolators from 1-day-old. Various doses of C. perfringens were given orally at 22 days, 9 days or at 1 day...... replaced by naturally occurring strains of C. perfringens in all groups but they persisted for considerably longer in chickens inoculated at 1-day-old or at 9 days than those at 22 days, indicating a possible resistance to colonization with increasing age. The findings emphasize the difficulties...... of establishing a reproducible model for infection with C. perfringens in broiler chickens....

  9. 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 ... juice. Commercially available cranberry juice cocktail also significantly reduced (P juice (P juice, were tested...... 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...

  10. 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

  11. Herpesviruses provide helper functions for avian adeno-associated parvovirus.

    Science.gov (United States)

    Bauer, H J; Monreal, G

    1986-01-01

    The avian herpesviruses infectious laryngotracheitis virus (ILTV) and herpesvirus of turkeys (HVT), as well as the mammalian herpesvirus pseudorabies virus (PRV) were able to provide complete helper activity for the production of infectious avian adeno-associated virus (AAAV) in chicken cells. The presence of AAAV in the infected chicken cell reduced the multiplication of HVT. ILTV or PRV, however, were not affected if used as helper viruses. Infectious AAAV was determined by an indirect immunofluorescence assay and infectious herpesvirus by plaque assays.

  12. 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.

  13. 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.

  14. Experimental Infections with Mycoplasma agalactiae Identify Key Factors Involved in Host-Colonization

    Science.gov (United States)

    Baranowski, Eric; Bergonier, Dominique; Sagné, Eveline; Hygonenq, Marie-Claude; Ronsin, Patricia; Berthelot, Xavier; Citti, Christine

    2014-01-01

    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. PMID:24699671

  15. Expression of circulating leucocytes before, during and after myiasis by Dermatobia hominis in experimentally infected rats.

    Science.gov (United States)

    Gonçalves, Jomara M; Pereira, Mônica C T; Evangelista, Luciene G; Leite, Antônio C R

    2007-01-01

    Expression of circulating white blood cells was investigated in rats (Rattus norvegicus) experimentally infected with larvae of Dermatobia hominis, the human bot fly. Leucocytes were counted prior to infection (control group) as well as at 6, 10, 15, 20 and 28 days post-infection (dpi) and at 7, 15, 30 and 60 days post-larval emergence (dple). Total leucocyte numbers did not differ markedly among the groups. Significant differences were registered when values from control and animals harboring each larval stage of D. hominis were compared; with crescent rank: L1-, L2-, control and L3-infected groups. Leucocyte numbers were significantly higher in the control, 15, 20 or 28 dpi groups than in the 6 dpi animals. Higher counts were observed in control, L2- or L3-infected rats than L1-infected animals. Neutrophils, eosinophils and both large and small lymphocytes were also counted and analyzed. Basophils and monocytes were insufficient in number to permit statistical studies. These results stimulate the continuity of the studies about the host-parasite relationship in the dermatobiosis.

  16. The effect of salinity on experimental infections of a Hematodinium sp. in blue crabs, Callinectes sapidus.

    Science.gov (United States)

    Coffey, Anna H; Li, Caiwen; Shields, Jeffrey D

    2012-06-01

    The parasitic dinoflagellate Hematodinium sp. parasitizes blue crabs along the Atlantic seaboard of the United States. Infections in blue crabs have only been reported from waters where salinity is >11 practical salinity units (psu). Blue crabs maintain a hyperosmotic internal concentration at low salinities (0-5 psu), roughly comparable to 24 psu, and should be capable of maintaining an infection in low-salinity waters even if Hematodinium spp. cells are intolerant of low salinities. We tested this notion by observing the effect of low salinity on the progression of disease in crabs experimentally infected with the parasite. Blue crabs were acclimated to 5 psu or 30 psu salinity treatments. They were inoculated with Hematodinium sp. and necropsied 3, 7, 10, and 15 days post-inoculation. The low-salinity treatment did not have an effect on the proliferation of Hematodinium sp. infections in blue crabs; moreover, a greater proportion of infections in crabs in the low-salinity treatment developed dinospore stages than did those in the high-salinity treatment, indicating that salinity may affect the development of the parasite. However, dinospores from in vitro cultures rapidly became inactive when held in salinities <15 psu. Our experiments indicate that Hematodinium spp. can develop in blue crabs at low salinities, but that the parasite is incapable of transmission in this environment, which explains the lack of natural infections in crabs at low salinities.

  17. Genomic Avenue to Avian Colisepticemia

    Science.gov (United States)

    Huja, Sagi; Oren, Yaara; Trost, Eva; Brzuszkiewicz, Elzbieta; Biran, Dvora; Blom, Jochen; Goesmann, Alexander; Gottschalk, Gerhard; Hacker, Jörg

    2015-01-01

    ABSTRACT Here we present an extensive genomic and genetic analysis of Escherichia coli strains of serotype O78 that represent the major cause of avian colisepticemia, an invasive infection caused by avian pathogenic Escherichia coli (APEC) strains. It is associated with high mortality and morbidity, resulting in significant economic consequences for the poultry industry. To understand the genetic basis of the virulence of avian septicemic E. coli, we sequenced the entire genome of a clinical isolate of serotype O78—O78:H19 ST88 isolate 789 (O78-9)—and compared it with three publicly available APEC O78 sequences and one complete genome of APEC serotype O1 strain. Although there was a large variability in genome content between the APEC strains, several genes were conserved, which are potentially critical for colisepticemia. Some of these genes are present in multiple copies per genome or code for gene products with overlapping function, signifying their importance. A systematic deletion of each of these virulence-related genes identified three systems that are conserved in all septicemic strains examined and are critical for serum survival, a prerequisite for septicemia. These are the plasmid-encoded protein, the defective ETT2 (E. coli type 3 secretion system 2) type 3 secretion system ETT2sepsis, and iron uptake systems. Strain O78-9 is the only APEC O78 strain that also carried the regulon coding for yersiniabactin, the iron binding system of the Yersinia high-pathogenicity island. Interestingly, this system is the only one that cannot be complemented by other iron uptake systems under iron limitation and in serum. PMID:25587010

  18. Avian hepatitis E virus, vaccines and methods of protecting against avian hepatitis-splenomegaly syndrome and mammalian hepatitis E

    OpenAIRE

    2009-01-01

    The present invention relates to a novel isolated avian hepatitis E virus having a nucleotide sequence set forth in SEQ ID NO:1 or its complementary strand. The invention further concerns immunogenic compositions comprising this new virus or recombinant products such as the nucleic acid and vaccines that protect an avian or mammalian species from viral infection or hepatitis-splenomegaly syndrome caused by the hepatitis E virus. Also included in the scope of the invention is a method for prop...

  19. Clinico-biochemical responses of dogs to experimental infection with Babesia canis

    Directory of Open Access Journals (Sweden)

    M. Konto

    2014-03-01

    Full Text Available Aim: A study on the clinical and biochemical parameters of Nigerian dogs experimentally infected with Babesia canis was conducted. Materials and Methods: A total of ten naive dogs of both sex and aged between 6 months to 1 year, were used for the study. They were divided into two groups of five each- A (control and B (infected. Dogs in group B were infected with 1ml of Babesia canis positive infectious inoculum, while those in group A were left as uninfected control. Following infection, clinical and biochemical responses were analyzed in group B and compared with those in group A. Results: Clinical signs were observed on the infected dogs 2 days post infection, which included fever (100%, increase in pulse (80%, tachycardia (60% and inappetence (100%; followed by anorexia (40% and lethargy (100% on day 3; on the fourth day, pallor of the mucous membrane of the mouth and eye (100% and emaciation (100%; on day five, muscle tremor (20% and respiratory distress (20%; on day six, nervousness (20%, drooling salivation (20% and haemoglobinuria (80; on day seven, mucoid ocular discharge (40%; followed by the death of one dog on day 8 post infection. Other clinical signs recorded between days 1-14 post infection were ascites, edematous swelling of the whole body and hair erection. The biochemical changes showed that there was a significant (p < 0.05 rise in alkaline phosphatase (ALP values in infected dogs (58.50±1.4 compared with the control group (51.67±1.6. Also, there was a significant rise (p < 0.05 in the alanine amino transferase (ALT values of infected group (15.70±1. 8 compared with the control values (8.27±2.0. However, the mean values for creatinine of infected group (78.10±1.2 was significantly lower (p < 0.05 than that of the control (91.73±1.3. Similarly, the glucose levels for infected group (3.80±2.3 were significantly (p < 0.05 lower than that of control (5.35±2.1. Conclusion: It can be concluded that the disease runs an acute

  20. Marginal vitamin A deficiency in pigs experimentally infected with Trichuris suis

    DEFF Research Database (Denmark)

    Pedersen, S; Saeed, I; Jensen, S K

    2001-01-01

    The development of an experimental model for marginal vitamin A deficiency in humans is of major interest, enabling the elucidation of possible interactions with helminth infections. We established a useful experimental model for human vitamin A deficiency in young pigs; deficiency was induced...... through a depletion method encompassing both sow and offspring. We report on a 2 x 2 study in which 18-week-old vitamin A deficient pigs and vitamin A sufficient littermates were infected with both of the intestinal nematodes Trichuris suis and Ascaris suum and followed for 14 weeks through 32 weeks...... of age. Forty-nine pigs were followed with respect to bodyweight, liver biopsies and blood samples for retinol concentration and faecal samples for parasite eggs and worms. Liver and serum concentrations of vitamin A were significantly diminished in the vitamin A deficient (VAD) group as compared...

  1. 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.

  2. Antibody response against Trichinella spiralis in experimentally infected rats is dose dependent

    Science.gov (United States)

    2011-01-01

    Domestic pigs are the main representatives of the domestic cycle of Trichinella spiralis that play a role in transmission to humans. In Europe, backyard pigs of small household farms are the most important risks for humans to obtain trichinellosis. Rats might play a role in the transmission of Trichinella spiralis from domestic to sylvatic animals and vice versa. In order to be able to investigate the role of wild rats in the epidemiology of T. spiralis in The Netherlands, we studied the dynamics of antibody response after T. spiralis infections in experimental rats, using infection doses ranging from very low (10 muscle larvae, ML, per rat) to very high (16 000 ML per rat). To evaluate the feasibility of rats surviving high infection doses with T. spiralis, clinical and pathological parameters were quantified. Serological tools for detecting T. spiralis in rats were developed to quantitatively study the correlation between parasite load and immunological response. The results show that an infection dose-dependent antibody response was developed in rats after infection with as low as 10 ML up to a level of 10 000 ML. A positive correlation was found between the number of recovered ML and serum antibody levels, although specific measured antibody levels correspond to a wide range of LPG values. Serum antibodies of rats that were infected even with 10 or 25 ML could readily be detected by use of the T. spiralis western blot 2 weeks post infection. We conclude that based on these low infection doses, serologic tests are a useful tool to survey T. spiralis in wild rats. PMID:22129040

  3. 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.

  4. Metabolic and histopathological profile of Rattus norvegicus (Wistar) experimentally infected by Angiostrongylus cantonensis (Chen, 1935).

    Science.gov (United States)

    Garcia, Juberlan Silva; Lúcio, Camila dos Santos; Bonfim, Tatiane Cristina dos Santos; Junior, Arnaldo Maldonado; Tunholi, Victor Menezes; Tunholi-Alves, Vinícius Menezes; Mota, Esther Maria; Simões, Raquel de Oliveira; Santana, André Campos; Hooper, Cleber; Pinheiro, Jairo; Bóia, Marcio Neves

    2014-02-01

    Eosinophilic meningitis is a disease characterized by increased eosinophils in the cerebrospinal fluid (CSF), which is the most commonly caused by invasion of the central nervous system by helminths, as occurs in Angiostrongylus cantonensis infections. The rodent Rattus norvegicus is the definitive natural host and humans act as accidental hosts and can become infected by eating raw or undercooked snails or food contaminated with infective L3 larvae. Recently in Brazil there have been four cases of eosinophilic meningitis due to ingestion of infected Achatina fulica. To evaluate biochemical and histopathological changes caused by this parasite, R. norvegicus were experimentally infected with 100 L3 larvae of A. cantonensis. After the anesthetic procedure, serum from the rodents was collected from the inferior vena cava for evaluation of the levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALKP), gamma-glutamyl transferase (GGT), total protein and its fractions. During the necropsy, the liver was collected and weighed. Then a 1-g fragment was extracted from the major lobe to quantify the hepatic glycogen and fragment remainder was taken from the same lobe and fixed in Milloning's formalin for histopathological examination. Additionally, helminths were collected from the brain and lungs of the rodents. The activities of AST, ALT, ALKP and GGT in the serum and hepatic glycogen increased in response to infection, while the levels of globulin and total protein increased only in the eighth week of infection and there was a reduction in the levels of serum glucose. Albumin and bilirubin concentrations remained stable during the experiment. Infection with A. cantonensis caused metabolic and histopathological changes in the rodents. This study can contribute to a better understanding of the relationship between A. cantonensis and R. norvegicus. Copyright © 2013 Elsevier Inc. All rights reserved.

  5. Macrophage activation associated with chronic murine cytomegalovirus infection results in more severe experimental choroidal neovascularization.

    Directory of Open Access Journals (Sweden)

    Scott W Cousins

    Full Text Available The neovascular (wet form of age-related macular degeneration (AMD leads to vision loss due to choroidal neovascularization (CNV. Since macrophages are important in CNV development, and cytomegalovirus (CMV-specific IgG serum titers in patients with wet AMD are elevated, we hypothesized that chronic CMV infection contributes to wet AMD, possibly by pro-angiogenic macrophage activation. This hypothesis was tested using an established mouse model of experimental CNV. At 6 days, 6 weeks, or 12 weeks after infection with murine CMV (MCMV, laser-induced CNV was performed, and CNV severity was determined 4 weeks later by analysis of choroidal flatmounts. Although all MCMV-infected mice exhibited more severe CNV when compared with control mice, the most severe CNV developed in mice with chronic infection, a time when MCMV-specific gene sequences could not be detected within choroidal tissues. Splenic macrophages collected from mice with chronic MCMV infection, however, expressed significantly greater levels of TNF-α, COX-2, MMP-9, and, most significantly, VEGF transcripts by quantitative RT-PCR assay when compared to splenic macrophages from control mice. Direct MCMV infection of monolayers of IC-21 mouse macrophages confirmed significant stimulation of VEGF mRNA and VEGF protein as determined by quantitative RT-PCR assay, ELISA, and immunostaining. Stimulation of VEGF production in vivo and in vitro was sensitive to the antiviral ganciclovir. These studies suggest that chronic CMV infection may serve as a heretofore unrecognized risk factor in the pathogenesis of wet AMD. One mechanism by which chronic CMV infection might promote increased CNV severity is via stimulation of macrophages to make pro-angiogenic factors (VEGF, an outcome that requires active virus replication.

  6. Quantification of Pasteurella multocida in experimentally infected pigs using a real-time PCR assay.

    Science.gov (United States)

    Tocqueville, V; Kempf, I; Paboeuf, F; Marois-Créhan, C

    2017-06-01

    The aim of the study was to quantify Pasteurella multocida in experimentally infected pigs using a new qPCR assay based on the sodA gene and validated with 35 P. multocida strains, including strains isolated from pigs with pneumonia, clinically healthy pigs (nasal cavities), and human infections. The specificity of the test was verified with a collection of 60 strains of bacterial species other than P. multocida. The estimated detection threshold was 10 genome equivalents per microliter. The amplification efficiency and value of the correlation coefficients were 95.5% (±3.5%) and 0.995 (±0.005), respectively. Analysis of P. multocida suspensions in Buffered Peptone Water Broth and of samples prepared from lungs experimentally spiked with P. multocida revealed detection thresholds of 1.4CFU/μl and 8.4CFU/μl, respectively. In live pigs, experimentally-infected, approximately 10(5), 10(7) and 10(8)genomeequivalents/ml of P. multocida DNA was detected on Day 8 post-infection in the nasal cavities, tonsils and trachea samples, respectively. In dead pigs, approximatively 10(7)genomeequivalents/ml of P. multocida DNA was detected in the lung tissue with pneumonia. The qPCR assay's diagnostic specificity and sensitivity were 100% and 96%, respectively. This new qPCR assay should be a very useful tool for controlling enzootic pneumonia and studying the dynamics of infections in pig herds. Copyright © 2017 Elsevier Ltd. All rights reserved.

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

    Science.gov (United States)

    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.

  9. Population dynamics of the minute intestinal trematode Haplorchis pumilio following experimental infection of young dogs

    DEFF Research Database (Denmark)

    Nissen, Sofie; Nguyen, Lan Anh; Thamsborg, Stig Milan

    2011-01-01

    to have the highest intensity of infection and contribute the most to the contamination of the environment with FZT eggs in the Nam Dinh province - a highly endemic area for FZTs. Given the free roaming and fish-eating behaviour of many dogs in rural Vietnam controlling the infection in dogs represents......Fishborne zoonotic trematodes (FZT) are highly prevalent in Southeast Asia. Recent studies on domestic animal’s role in the transmission of FZT in Northern Vietnam found that the most prevalent FZT was Haplorchis pumilio. The importance of dogs, cats and pigs was assessed, and dogs were found...... a major challenge. In particular knowledge is needed on the importance of the dog as reservoir to make evidence-based recommendations for control of FZT. On this background, we conducted an experimental infection in dogs with H. pumilio to elucidate population dynamics and host reactions. Eight household...

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

    Directory of Open Access Journals (Sweden)

    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.

  11. [Experimental infection of goats with Schistosoma bovis and S. curassoni: comparative pathogenic effects].

    Science.gov (United States)

    Labbo, R; Boulanger, D; Brémond, P; Chippaux, J P

    2007-03-01

    Specific mortality and morbidity have been quantified in goats experimentally infected with Schistosoma bovis or S. curassoni strains from Niger. The study involved nine animals followed during 380 days after infection with, respectively, 1,800 or 2,400 cercariae. S. bovis was significatively more pathogenic than S. curossoni in terms of mortality, weight loss and packed cell volume decrease. In addition, the intensity of clinical symptoms was significatively and positively correlated to the levels of fecal egg excretion. Compared to non-infected controls, a growth differential of, respectively, 1,600 and 880 grams per month should incite to consider S. bovis and S. curassoni as parasites of serious economical impact in sahelian countries.

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

    Directory of Open Access Journals (Sweden)

    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. The Healing Effect of Licorice on Pseudomonas aeruginosa Infected Burn Wounds in Experimental Rat Model

    OpenAIRE

    Tanideh, Nader; Rokhsari, Pedram; Mehrabani, Davood; Mohammadi Samani, Soleiman; Sabet Sarvestani, Fatemeh; Ashraf, Mohammad Javad; Koohi Hosseinabadi, Omid; Shamsian, Shahram; AHMADI, Nasrollah

    2014-01-01

    BACKGROUND Burn is still one of the most devastating injuries in emergency medicine while improvements in wound healing knowledge and technology have resulted into development of new dressings. This study was undertaken to evaluate the healing effect of licorice in Pseudomonas aeruginosa infected burn wounds of experimental rat model. METHODS One hundred and twenty female Sprague-Dawley rats were randomly allocated to 4 equal groups. Group A received silver sulfadiazine ointment, Group B rece...

  14. Treatment of pigs experimentally infected with Mycoplasma hyopneumoniae, Pasteurella multocida, and Actinobacillus pleuropneumoniae with various antibiotics.

    OpenAIRE

    Stipkovits, L.; Miller, D; Glavits, R; Fodor, L; Burch, D

    2001-01-01

    The authors have performed a comparative study of the efficacy of various in-feed medications for the treatment of 5- to 6-week-old specific pathogen-free (SPF) piglets experimentally infected on day 1 with Mycoplasma hyopneumoniae, on day 8 with Pasteurella multocida (serotype A), and on day 15 with Actinobacillus pleuropneumoniae (serotype 2). The treatment started on day 9 and continued for 12 consecutive days, then the piglets were euthanized for examination of macroscopic, histologic, an...

  15. Effect of resinous extract from Commiphora swynnertonii (Burrt) on experimental coccidial infection in chickens.

    Science.gov (United States)

    Bakari, Gaymary G; Max, Robert A; Mdegela, Robinson H; Phiri, Elliot C J; Mtambo, Mkumbukwa M A

    2013-02-01

    A crude resinous extract from Commiphora swynnertonii was tested against an experimental coccidial infection in local chickens. A total of 80 growing chickens were randomly assigned into five groups, which received different treatments. Chickens in G1 were not infected with coccidian oocysts and therefore served as a negative control. All chickens in G2, G3, G4 and G5 were infected through oral administration of coccidian oocysts suspension at a dosed rate of 1.5 × 10(4) Eimeria spp. oocysts per bird. Starting from day 3 post-infection (p.i), chickens in different groups were treated for 7 consecutive days as follows: G1 and G2 (positive control) received 5 ml of normal saline as placebo, G3 and G4 were given the extract at 400 and 800 mg/kg bodyweight whereas G5 received anticoccidial drug. Clinical signs, bodyweights, oocysts counts and mortality rates were observed regularly. Results showed that oral administration of the resinous extract to chickens with coccidiosis significantly reduced mortality rate from 94 to 25 % and oocysts counts from 1.03 × 10(5) to 6.55 × 10(3) oocysts/g faeces (p < 0.05). Also a body condition score chart indicated less severe clinical signs of the disease in the groups which received the extract. Mean daily body weights were slightly reduced by the administration of the extract but this effect disappeared by day 7 p.i. These findings clearly indicate that resinous extract from C. swynnertonii has significant anticoccidial effect against experimental Eimeria spp. infection in chickens. A larger field trial to validate the use of the extract in chickens naturally infected with Eimeria spp. is required.

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

    Directory of Open Access Journals (Sweden)

    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.

  17. Cellular immune responses of the rat to experimental infection with Dermatophilus congolensis.

    Science.gov (United States)

    Woodman, J P; Morrow, A M; Heron, I

    1990-11-01

    The host cell-mediated immune response was examined following experimentally-induced infection of rats with Dermatophilus congolensis, the causal agent of the skin disease dermatophilosis. Mononuclear cells (MC) isolated from Wistar rats 10 days following the induction of a third infection underwent a strong and specific proliferative response, as assessed by a [3H]thymidine incorporation assay, when cultured with various concentrations of inactivated D. congolensis cocci. Using specific monoclonal antibodies in an indirect fluorescent antibody test, this in vitro response was found to be characterised by a large expansion of the W3/25 (T-helper phenotype) population to form 56% of the total. Finally, the primed and stimulated MC were assessed for their ability to produce factors capable of inhibiting macrophage migration. The culture supernatants of D. congolensis-stimulated MC from infected rats caused significant migration inhibition of normal rat peritoneal exudate cells, whilst the supernatants of similarly-stimulated MC from naive rats failed to cause significant inhibition. The results show that a MC subpopulation becomes primed following experimentally-induced infection with D. congolensis and becomes activated after subsequent, in vitro, exposure.

  18. Experimental basis for the clinical epidemiology of fungal infections. A review.

    Science.gov (United States)

    Schaffner, A

    1989-10-01

    Based on the concept that the agents of deep fungal infections can be divided into primary pathogens and opportunists the experimental basis for the clinical epidemiology of mycoses is outlined. Kinetics of experimental infections with opportunists and primary pathogens discriminate between the two fungal categories. Natural resistance eliminates opportunists and prevents the establishment of progressive infection in the normal host. Primary pathogens call upon mechanisms of adoptive cell mediated immunity for their control. Therefore athymic mice which are not more susceptible to opportunists than control mice, cannot control infection with primary pathogens. In order to induce comparable overwhelming opportunistic mycoses with reasonable challenge doses, non-specific phagocytic resistance has to be eliminated. In agreement with in vivo studies, in vitro studies of the susceptibility of fungi to killing by phagocytes point out, that the susceptibility of the tissue phase of fungi to killing by "immunologically unarmed" phagocytes discriminates between opportunists and primary pathogens. In order to restrain primary pathogenic fungi, phagocytes have also in vitro to call upon adoptive, T cell-dependent immune mechanisms, which appear superfluous for control of opportunists. This difference explains the discrepant opportunistic proclivities of the two fungal categories. Patients with defective phagocytic defenses are prone to opportunistic mycoses, while deficient cell mediated immunity results in a greater vulnerability to primary pathogens.

  19. Semen variables of sheep (Ovis aries) experimentally infected with Toxoplasma gondii.

    Science.gov (United States)

    Lopes, W D Z; Costa, A J; Souza, F A; Rodrigues, J D F; Costa, G H N; Soares, V E; Silva, G S

    2009-04-01

    The influence of Toxoplasma gondii on semen variables and sperm morphology of sheep was evaluated in eight reproductive males distributed into three experimental groups: GI, three sheep inoculated with 2.0x10(5) of P strain oocytes; GII, three sheep infected with 1.0x10(6) of RH strain tachyzoites and; GIII two control sheep. Clinical (rectal temperature, cardiac and respiratory frequencies), parasite and serology exams (IIF) were realized. Sperm variables (volume, motility, vigor and concentration) and semen morphology for each sheep were also evaluated. Thus, semen and blood collections were assessed on post-inoculation days (PIDs)-1,3,5,7,11,14 and weekly thereafter up to PID 70. Clinical alterations were observed (hypothermia and anorexia) in infected sheep from groups GI and GII. Parasitic outbreaks were detected in five sheep. All the infected sheep produced antibodies against T. gondii from PID 5 onwards, reaching a peak of 4096 and 8192 for group GI and GII sheep, respectively. Differences (P<0.05) were observed regarding the ejaculate volume between the inoculated groups (oocytes and tachyzoites) and control. Even though experimental toxoplasmic infection resulted in clinical symptomology in the inoculated sheep, the minimal alterations in sperm pathologies could not be directly attributed to T. gondii.

  20. Protein profile of lambs experimentally infected with Haemonchus contortus and supplemented with selenium and copper.

    Science.gov (United States)

    Fausto, Guilherme Costa; Pivoto, Felipe Lamberti; Costa, Márcio Machado; dos Anjos Lopes, Sônia Terezinha; França, Raqueli Teresinha; Molento, Marcelo Beltrão; Minervino, Antonio Humberto Hamad; da Rocha, João Batista Teixeira; Leal, Marta Lizandra do Rêgo

    2014-08-05

    Gastrointestinal nematodes cause significant economic losses in the sheep industry, with frequent reports of anthelmintic resistance. Therefore, alternative methods to control these parasites are necessary. Thus, the aim of the present study was to assess the effect of treatment with selenium and copper on the protein profile of sheep that were experimentally infected with Haemonchus contortus. Twenty-eight lambs were experimentally infected with H. contortus and divided into four experimental groups as follow: G1--untreated animals; G2--treated with sodium selenite; G3--treated with copper; G4--treated with sodium selenite and copper. The serum protein, body weight and egg count per gram of feces (EPG) were assessed at the baseline and after 20, 40, 60 and 80 days. The parasite burden was assessed 80 days after the beginning of the experiment. Higher levels of total protein and gamma globulin were observed in the lambs treated with sodium selenite and copper on D80. Copper acted as a growth promoter. The copper-supplemented groups exhibited higher daily and total weight gain. The association of selenium and copper altered the protein profile of sheep. Copper and selenium supplementation reduced EPG and worm burden at the end of the experiment. To the best of our knowledge, this is the first study to demonstrate the positive effect of the combined parenteral supplementation of Se and Cu on H. contortus infection. This injectable supplementation could be used as an auxiliary method to control H. contortus in sheep.

  1. Genetic and biological characterisation of an avian-like H1N2 swine influenza virus generated by reassortment of circulating avian-like H1N1 and H3N2 subtypes in Denmark

    Science.gov (United States)

    2013-01-01

    Background The influenza A virus subtypes H1N1, H1N2 and H3N2 are the most prevalent subtypes in swine. In 2003, a reassorted H1N2 swine influenza virus (SIV) subtype appeared and became prevalent in Denmark. In the present study, the reassortant H1N2 subtype was characterised genetically and the infection dynamics compared to an “avian-like” H1N1 virus by an experimental infection study. Methods Sequence analyses were performed of the H1N2 virus. Two groups of pigs were inoculated with the reassortant H1N2 virus and an “avian-like” H1N1 virus, respectively, followed by inoculation with the opposite subtype four weeks later. Measurements of HI antibodies and acute phase proteins were performed. Nasal virus excretion and virus load in lungs were determined by real-time RT-PCR. Results The phylogenetic analysis revealed that the reassorted H1N2 virus contained a European “avian-like” H1-gene and a European “swine-like” N2-gene, thus being genetically distinct from most H1N2 viruses circulating in Europe, but similar to viruses reported in 2009/2010 in Sweden and Italy. Sequence analyses of the internal genes revealed that the reassortment probably arose between circulating Danish “avian-like” H1N1 and H3N2 SIVs. Infected pigs developed cross-reactive antibodies, and increased levels of acute phase proteins after inoculations. Pigs inoculated with H1N2 exhibited nasal virus excretion for seven days, peaking day 1 after inoculation two days earlier than H1N1 infected pigs and at a six times higher level. The difference, however, was not statistically significant. Pigs euthanized on day 4 after inoculation, had a high virus load in all lung lobes. After the second inoculation, the nasal virus excretion was minimal. There were no clinical sign except elevated body temperature under the experimental conditions. Conclusions The “avian-like” H1N2 subtype, which has been established in the Danish pig population at least since 2003, is a reassortant

  2. Gambaran Sel Eosinofil, Monosit, dan Basofil Setelah Pemberian Spirulina pada Ayam yang Diinfeksi Virus Flu Burung (OBSERVATION OF EOSINOPHILS, MONOCYTES, AND BASOPHILS AFTER TREATED WITH SPIRULINA IN CHICKENS THAT INFECTED WITH AVIAN INFLUENZA VIRUS

    Directory of Open Access Journals (Sweden)

    Widya Paramita Lokapirnasari

    2015-05-01

    Full Text Available High Pathogenecity Avian Influenza (HPAI viruses have high virulence and can frequently causesudden death on birds. The aims of this research was to know the role of Spirulina to a number ofmonocytes and lymphocytes in the blood of chickens which infected with the H5N1 virus. This researchconsisted of three levels of treatment in which each level given Spirulina 0%, 10%, 20% in the fresh wateralgae as drinking water. Each treatment consisted of seven replicates, and the treatment was done sincethe chickens at age 19 until 44 days ( for 25 days. Artificial infection of the chickens with the virus waschallenged by using AI (H5N1 104 EID 50 (A/Ck/Indonesia/BL/03 with route to the respiratory tract (nosedrops 0,1 mL starting on day 19. The results showed that there were a significant difference (p<0.05 ontreatment that given Spirulina at doses of 0%, 10% and 20% for the number ofn monocytes, eosinophils,whereas no significant difference (p > 0.05 was observed in basophils.

  3. Ducks as Sentinels for Avian Influenza in Wild Birds

    Science.gov (United States)

    Baumer, Anette; Revilla-Fernández, Sandra; Beer, Martin; Wodak, Eveline; Fink, Maria; Greber, Norbert; Harder, Timm C.; Wilking, Hendrik; Brunhart, Iris; Matthes, Doris; Kraatz, Ulf; Strunk, Peter; Fiedler, Wolfgang; Fereidouni, Sasan R.; Staubach, Christoph; Conraths, Franz J.; Griot, Chris; Mettenleiter, Thomas C.; Stärk, Katharina D.C.

    2009-01-01

    To determine the effectiveness of ducks as sentinels for avian influenza virus (AIV) infection, we placed mallards in contact with wild birds at resting sites in Germany, Austria, and Switzerland. Infections of sentinel birds with different AIV subtypes confirmed the value of such surveillance for AIV monitoring. PMID:19861060

  4. Effects of atmospheric ammonia on young pigs experimentally infected with Ascaris suum

    Energy Technology Data Exchange (ETDEWEB)

    Drummond, J.G.; Curtis, S.E.; Simon, J.; Norton, H.W.

    1981-06-01

    Effects of atmospheric ammonia at 69.4 mg/m3 (100 ppm) on productive performance and respiratory tract health of young pigs (starting body weight averaged 7.5 kg) experimentally infected with Ascaris suum (50,000 embryonated ova administered by gavage when pigs were 5 weeks of age) were studied in 5 trials of 4 weeks each (when pigs were 5 to 9 weeks of age). Effects of atmospheric-ammonia exposure and ascarid infection on growth were additive. Compared with controls, percentage reductions in average daily gain were 32%, 28%, and 61% for ammonia-exposed, ascarid-infected, and combined ammonia plus ascarid groups, respectively. Ammonia exposure or ascarid infection alone depressed feed disappearance by 18%. Effects of the 2 factors were additive, resulting in a 35% reduction in feed disappearance. Pigs exposed to the combined factors had an average gain/feed ratio of 0.518, which was less than that of control pigs (0.546), but was greater than that of pigs exposed to atmospheric ammonia (0.489) or pigs infected with ascarids (0.501) alone. Liver scarring, due to larval migration, was not affected by ammonia exposure. Larval migration through the respiratory tract was not confirmed histopathologically in pigs killed 4 weeks after inoculation. A supplementary experiment was conducted which demonstrated that residual evidence of previous pulmonary larval migration was present 2 weeks after inoculation.

  5. Mucosal Immune Responses of Mice Experimentally Infected with Pygidiopsis summa (Trematoda: Heterophyidae)

    Science.gov (United States)

    Chai, Jong-Yil; Park, Young-Jin; Park, Jae-Hwan; Jung, Bong-Kwang

    2014-01-01

    Mucosal immune responses against Pygidiopsis summa (Trematoda: Heterophyidae) infection were studied in ICR mice. Experimental groups consisted of group 1 (uninfected controls), group 2 (infection with 200 metacercariae), and group 3 (immunosuppression with Depo-Medrol and infection with 200 metacercariae). Worms were recovered in the small intestine at days 1, 3, 5, and 7 post-infection (PI). Intestinal intraepithelial lymphocytes (IEL), mast cells, and goblet cells were counted in intestinal tissue sections stained with Giemsa, astra-blue, and periodic acid-Schiff, respectively. Mucosal IgA levels were measured by ELISA. Expulsion of P. summa from the mouse intestine began to occur from days 3-5 PI which sustained until day 7 PI. The worm expulsion was positively correlated with proliferation of IEL, mast cells, goblet cells, and increase of IgA, although in the case of mast cells significant increase was seen only at day 7 PI. Immunosuppression suppressed all these immune effectors and inhibited worm reduction in the intestine until day 7 PI. The results suggested that various immune effectors which include IEL, goblet cells, mast cells, and IgA play roles in regulating the intestinal mucosal immunity of ICR mice against P. summa infection. PMID:24623878

  6. Galectin-3: A Friend but Not a Foe during Trypanosoma cruzi Experimental Infection

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    Aline A. da Silva

    2017-11-01

    Full Text Available Trypanosoma cruzi interacts with host cells, including cardiomyocytes, and induces the production of cytokines, chemokines, metalloproteinases, and glycan-binding proteins. Among the glycan-binding proteins is Galectin-3 (Gal-3, which is upregulated after T. cruzi infection. Gal-3 is a member of the lectin family with affinity for β-galactose containing molecules; it can be found in both the nucleus and the cytoplasm and can be either membrane-associated or secreted. This lectin is involved in several immunoregulatory and parasite infection process. Here, we explored the consequences of Gal-3 deficiency during acute and chronic T. cruzi experimental infection. Our results demonstrated that lack of Gal-3 enhanced in vitro replication of intracellular parasites, increased in vivo systemic parasitaemia, and reduced leukocyte recruitment. Moreover, we observed decreased secretion of pro-inflammatory cytokines in spleen and heart of infected Gal-3 knockout mice. Lack of Gal-3 also led to elevated mast cell recruitment and fibrosis of heart tissue. In conclusion, galectin-3 expression plays a pivotal role in controlling T. cruzi infection, preventing heart damage and fibrosis.

  7. Cardiac plexus of dogs experimentally infected with Trypanosoma cruzi: inflammatory lesions and quantitative studies

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    Marcelo V. Caliari

    1995-03-01

    Full Text Available Qualitative and quantitative aspects of the superficial and profound cardiac plexus of dogs experimentally infected with Be-62 and Be-78 strains of Trypanosoma cruzi were studied. Animals were autopsied in the acute phase of infection. The inflammatory process, lesions and number of parasites were more intense and frequent in animals infected with the Be-78 strain than in those infected with Be-62. Despite this, no statistically significant differences could be found between the number of neuron bodies in the ganglia of infected and control dogs.Foi realizado estudo qualitativo e quantitativo dos plexos cardíacos superficiais e profundos em cães inoculados com o Trypanosoma cruzi das cepas Be-62 e Be-78 e sacrificados na fase aguda. O processo inflamatório, as lesões e o parasitismo dos plexos foram mais intensos e frequentes nos animais inoculados com a cepa Be-78 do que naqueles inoculados com a cepa Be- 62. Apesar deste fato, não foi verificada diferença estatisticamente significativa entre o número de corpos de neurônio por gânglio dos animais chagásicos e os controles.

  8. Testing sex ratio theory with the malaria parasite Plasmodium mexicanum in natural and experimental infections.

    Science.gov (United States)

    Neal, Allison T; Schall, Jos J

    2014-04-01

    The malaria parasite (Plasmodium) life history accords well with the assumptions of local mate competition (LMC) of sex ratio theory. Within a single meal of the blood-feeding vector, sexually dimorphic gametocyte cells produce gametes (females produce one, males several) that mate and undergo sexual recombination. The theory posits several factors drive the Plasmodium sex ratio: male fecundity (gametes/male gametocyte), number and relative abundance of parasite clones, and gametocyte density. We measured these traits for the lizard malaria parasite, Plasmodium mexicanum, with a large sample of natural infections and infections from experiments that manipulated clonal diversity. Sex ratio in single-clone infections was slightly female-biased, but matched predictions of theory for this low-fecundity species. Sex ratio was less female-biased in clonally diverse infections as predicted by LMC for the experimental, but not natural infections. Gametocyte density was not positively related to sex ratio. These results are explained by the P. mexicanum life history of naturally low clonal diversity and high gametocyte production. This is the first study of a natural malaria system that examines all traits relevant to LMC in individual vertebrate hosts and suggests a striking example of sex ratio theory having significance for human public health. © 2013 The Author(s). Evolution © 2013 The Society for the Study of Evolution.

  9. Tenacity of low-pathogenic avian influenza viruses in different types of poultry litter.

    Science.gov (United States)

    Reis, A; Stallknecht, D; Ritz, C; García, M

    2012-08-01

    To determine the risk of infection associated with exposure to low-pathogenic avian influenza (AI) virus-contaminated poultry litter, the tenacity of low pathogenic A/Ck/CA/431/00(H6N2), A/Mallard/MN/355779/00(H5N2), and A/turkey/Ohio/313053/04(H3N2) was evaluated. Viral stocks were incubated with poultry litter from commercial flocks at 25°C. Three types of poultry litter, wood shavings, shavings plus gypsum, and shavings plus peanut hulls, from commercial broiler flocks were used. The 3 low-pathogenic avian influenza viruses retained infectivity for one day in wood shavings and shavings plus peanut hulls litter types, whereas in wood shavings plus gypsum, litter viruses remained infective for up to 3 d. In contrast to the survivability in litter, all the viruses maintained infectivity in water for 4 d at titers of log(10)4.5. The infectivity of A/Ck/CA/431/00(H6N2) shed by experimentally infected layers, broilers, and turkeys was retained for one day, independently of the type of litter. In commercial production where a high density of birds are housed, the viral load shed by an infected flock will be significantly higher than the viral load shed 3 d postinfection obtained under the experimental conditions used in this study. Therefore proper management and disposal of poultry by products, such as windrow composting of litter and the composting of carcasses during an AI outbreak should be implemented.

  10. Clinico-pathological studies in cattle experimentally infected with Taenia saginata eggs : research communication

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    A. Oryan

    1998-07-01

    Full Text Available Calves 1-2 months old were experimentally infected with eggs of Taenia saginata and clinical and haematological deviations, development and distribution of cysticerci and pathological changes were recorded. The calves infected with 5 000, 10 000 or 50 000 eggs showed an increase in pulse and respiratory rates. The animals that received 50 000 eggs had significantly increased pulse (p<0.05 and respiratory rates (p<0.005. The symptoms were more severe in young, 30-day-old calves infected with 50 000 eggs. Haemoglobin concentration, haematocrit values and red blood cell count decreased, but white blood cell count increased slightly. Lymphocytes and eosinophils also increased up to 88%and 14% (p<0.05, respectively. Most of the cysticerci were not fully formed 1 month post-infection, but at 2 months the cysts were fully mature and at 4 months, some cysts had degenerated. There was no uniformpattern of distribution of cysticerci in the body of infected calves, but the most commonly affected sites were masseter and heart muscles, followed by diaphragm, tongue and other skeletal muscles. The maximum concentration of 8-14 cysticerci per 10 g of tissue was recorded in masseter muscles and heart. The affected parts revealed tissue reactions that included pressure atrophy, necrosis and fibrosis. Microscopically, the lesions comprised infiltration with lymphocytes, plasma cells, eosinophils and macrophages, fibrosis, necrosis and calcification. The tissue reaction was severe in calves infected with 50 000 eggs. The severity of clinical signs, haematological and pathological changes depended mostly on the age of the animals and dose of infection.

  11. Experimental Infection of Rabbits with Rabbit and Genotypes 1 and 4 Hepatitis E Viruses

    Science.gov (United States)

    Ma, Hongxia; Zheng, Lin; Liu, Yunbo; Zhao, Chenyan; Harrison, Tim J.; Ma, Yuyuan; Sun, Shuhua; Zhang, Jingang; Wang, Youchun

    2010-01-01

    Background A recent study provided evidence that farmed rabbits in China harbor a novel hepatitis E virus (HEV) genotype. Although the rabbit HEV isolate had 77–79% nucleotide identity to the mammalian HEV genotypes 1 to 4, their genomic organization is very similar. Since rabbits are used widely experimentally, including as models of infection, we investigated whether they constitute an appropriate animal model for human HEV infection. Methods Forty-two SPF rabbits were divided randomly into eleven groups and inoculated with six different isolates of rabbit HEV, two different doses of a second-passage rabbit HEV, and with genotype 1 and 4 HEV. Sera and feces were collected weekly after inoculation. HEV antigen, RNA, antibody and alanine aminotransferase in sera and HEV RNA in feces were detected. The liver samples were collected during necropsy subject to histopathological examination. Findings Rabbits inoculated with rabbit HEV became infected with HEV, with viremia, fecal virus shedding and high serum levels of viral antigens, and developed hepatitis, with elevation of the liver enzyme, ALT. The severity of disease corresponded to the infectious dose (genome equivalents), with the most severe hepatic disease caused by strain GDC54-18. However, only two of nine rabbits infected with HEV genotype 4, and none infected with genotype 1, developed hepatitis although six of nine rabbits inoculated with the genotype 1 HEV and in all rabbits inoculated with the genotype 4 HEV seroconverted to be positive for anti-HEV IgG antibody by 14 weeks post-inoculation. Conclusions These data indicate that rabbits are an appropriate model for rabbit HEV infection but are not likely to be useful for the study of human HEV. The rabbit HEV infection of rabbits may provide an appropriate parallel animal model to study HEV pathogenesis. PMID:20161794

  12. Experimental infection of rabbits with rabbit and genotypes 1 and 4 hepatitis E viruses.

    Science.gov (United States)

    Ma, Hongxia; Zheng, Lin; Liu, Yunbo; Zhao, Chenyan; Harrison, Tim J; Ma, Yuyuan; Sun, Shuhua; Zhang, Jingang; Wang, Youchun

    2010-02-11

    A recent study provided evidence that farmed rabbits in China harbor a novel hepatitis E virus (HEV) genotype. Although the rabbit HEV isolate had 77-79% nucleotide identity to the mammalian HEV genotypes 1 to 4, their genomic organization is very similar. Since rabbits are used widely experimentally, including as models of infection, we investigated whether they constitute an appropriate animal model for human HEV infection. Forty-two SPF rabbits were divided randomly into eleven groups and inoculated with six different isolates of rabbit HEV, two different doses of a second-passage rabbit HEV, and with genotype 1 and 4 HEV. Sera and feces were collected weekly after inoculation. HEV antigen, RNA, antibody and alanine aminotransferase in sera and HEV RNA in feces were detected. The liver samples were collected during necropsy subject to histopathological examination. Rabbits inoculated with rabbit HEV became infected with HEV, with viremia, fecal virus shedding and high serum levels of viral antigens, and developed hepatitis, with elevation of the liver enzyme, ALT. The severity of disease corresponded to the infectious dose (genome equivalents), with the most severe hepatic disease caused by strain GDC54-18. However, only two of nine rabbits infected with HEV genotype 4, and none infected with genotype 1, developed hepatitis although six of nine rabbits inoculated with the genotype 1 HEV and in all rabbits inoculated with the genotype 4 HEV seroconverted to be positive for anti-HEV IgG antibody by 14 weeks post-inoculation. These data indicate that rabbits are an appropriate model for rabbit HEV infection but are not likely to be useful for the study of human HEV. The rabbit HEV infection of rabbits may provide an appropriate parallel animal model to study HEV pathogenesis.

  13. Experimental infection of rabbits with rabbit and genotypes 1 and 4 hepatitis E viruses.

    Directory of Open Access Journals (Sweden)

    Hongxia Ma

    Full Text Available BACKGROUND: A recent study provided evidence that farmed rabbits in China harbor a novel hepatitis E virus (HEV genotype. Although the rabbit HEV isolate had 77-79% nucleotide identity to the mammalian HEV genotypes 1 to 4, their genomic organization is very similar. Since rabbits are used widely experimentally, including as models of infection, we investigated whether they constitute an appropriate animal model for human HEV infection. METHODS: Forty-two SPF rabbits were divided randomly into eleven groups and inoculated with six different isolates of rabbit HEV, two different doses of a second-passage rabbit HEV, and with genotype 1 and 4 HEV. Sera and feces were collected weekly after inoculation. HEV antigen, RNA, antibody and alanine aminotransferase in sera and HEV RNA in feces were detected. The liver samples were collected during necropsy subject to histopathological examination. FINDINGS: Rabbits inoculated with rabbit HEV became infected with HEV, with viremia, fecal virus shedding and high serum levels of viral antigens, and developed hepatitis, with elevation of the liver enzyme, ALT. The severity of disease corresponded to the infectious dose (genome equivalents, with the most severe hepatic disease caused by strain GDC54-18. However, only two of nine rabbits infected with HEV genotype 4, and none infected with genotype 1, developed hepatitis although six of nine rabbits inoculated with the genotype 1 HEV and in all rabbits inoculated with the genotype 4 HEV seroconverted to be positive for anti-HEV IgG antibody by 14 weeks post-inoculation. CONCLUSIONS: These data indicate that rabbits are an appropriate model for rabbit HEV infection but are not likely to be useful for the study of human HEV. The rabbit HEV infection of rabbits may provide an appropriate parallel animal model to study HEV pathogenesis.

  14. Antibiotic embedded absorbable prosthesis for prevention of surgical mesh infection: experimental study in rats.

    Science.gov (United States)

    Suárez-Grau, J M; Morales-Conde, S; González Galán, V; Martín Cartes, J A; Docobo Durantez, F; Padillo Ruiz, F J

    2015-04-01

    Ventral hernias are a common problem in a general surgery and hernioplasty is an integral part of a general surgeon's practice. The use of prosthetic material has drastically reduced the risk of recurrence, but has introduced additional potential complications such as surgical wound infections, adhesion formation, graft rejection, etc. The development of a wound infection in a hernia that is repaired with a prosthetic material is a grave complication, often requiring removal of the prosthesis. This experimental study examined efficacy of completely absorbable, hydrophilic, PGA-TMC (polyglycolic acid-trimethylene carbonate) prosthesis impregnated with antibiotic for reduction of infectious complications. Antibiotic-impregnated PGA-TMC prostheses were placed intraperitoneally in 90 Wistar white rats that were randomized and distributed into four groups. Group 0 (23 rats): there were placed PGA-TMC prosthesis without antibiotic impregnation (control group). Group 1 (25 rats): meshes were placed and infected later with 1 × 10(8) UFC of S. aureus/1 ml/2 cm(2) (Staphylococcus aureus ATCC 6538 American Type Culture Collection, Rockville, MD). Group 2 (21 rats): cefazolin-impregnated prostheses were placed (1 g × 100 ml, at the rate of 1 ml/cm(2) of prosthesis) and were subsequently infected with the same bacterial inoculate. Group 3 (21 rats): cefazolin-impregnated prostheses with double quantity of cefazolin and infected. A week later these animals were killed and specimens were extracted for bacterial quantification and histological studies. Evident decrease of bacterial colonization was observed in series 2 and 3 [the ones impregnated with cefazolin, in comparison with the group 1 (infected without previous antibiotic impregnation)] with statistically significant results (p prosthesis when placing it in contact with intraabdominal viscera. However, cefazolin impregnation of the mesh has reduced an adhesion formation, mostly when the infection reached a

  15. Helicobacter pylori infection reduces disease severity in an experimental model of multiple sclerosis

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    Katherine eCook

    2015-02-01

    Full Text Available Recent research has demonstrated that infection with the bacterial pathogen Helicobacter pylori is less common amongst patients with multiple sclerosis (MS, an inflammatory demyelinating disease of the central nervous system (CNS. We compared the prevalence of H. pylori amongst MS patients and healthy controls, and also investigated the impact of this infection on an animal model for MS, experimental autoimmune encephalomyelitis (EAE.The H. pylori status of 71 MS patients and 42 healthy controls was determined by serology. Groups of C57BL/6 mice were infected with H. pylori, or given a placebo, prior to inducing EAE. Clinical scores were assessed for all mice, and spleens and spinal cord tissue were harvested. CD4+ T cell subsets were quantified by flow cytometry, and T cell proliferation assays were performed.In MS patients the seroprevalence of H. pylori was half that of healthy controls (p=0.018. Over three independent experiments, prior H. pylori infection had a moderate effect in reducing the severity of EAE (p = 0.012. In line with this, the antigen-specific T cell proliferative responses of infected animals were significantly reduced (p=0.001, and there was a 4-fold reduction in the number of CD4+ cells in the CNS. CD4+ populations in both the CNS and the spleens of infected mice also contained greatly reduced proportions of IFNγ+, IL-17+, T-bet+, and RORγt+ cells, but the proportions of Foxp3+ cells were equivalent. There were no differences in the frequency of splenic CD4+cells expressing markers of apoptosis between infected and uninfected animals.H. pylori was less prevalent amongst MS patients. In mice, the infection exerted some protection against EAE, inhibiting both Th1 and Th17 responses. This could not be explained by the presence of increased numbers of Foxp3+ regulatory T cells, or T cell apoptosis. This is the first direct experimental evidence showing that H. pylori may provide protection against inflammatory demyelination

  16. Young Sprague Dawley rats infected by Plasmodium berghei: A relevant experimental model to study cerebral malaria.

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    Sokhna Keita Alassane

    Full Text Available Cerebral malaria (CM is the most severe manifestation of human malaria yet is still poorly understood. Mouse models have been developed to address the subject. However, their relevance to mimic human pathogenesis is largely debated. Here we study an alternative cerebral malaria model with an experimental Plasmodium berghei Keyberg 173 (K173 infection in Sprague Dawley rats. As in Human, not all infected subjects showed cerebral malaria, with 45% of the rats exhibiting Experimental Cerebral Malaria (ECM symptoms while the majority (55% of the remaining rats developed severe anemia and hyperparasitemia (NoECM. These results allow, within the same population, a comparison of the noxious effects of the infection between ECM and severe malaria without ECM. Among the ECM rats, 77.8% died between day 5 and day 12 post-infection, while the remaining rats were spontaneously cured of neurological signs within 24-48 hours. The clinical ECM signs observed were paresis quickly evolving to limb paralysis, global paralysis associated with respiratory distress, and coma. The red blood cell (RBC count remained normal but a drastic decrease of platelet count and an increase of white blood cell numbers were noted. ECM rats also showed a decrease of glucose and total CO2 levels and an increase of creatinine levels compared to control rats or rats with no ECM. Assessment of the blood-brain barrier revealed loss of integrity, and interestingly histopathological analysis highlighted cyto-adherence and sequestration of infected RBCs in brain vessels from ECM rats only. Overall, this ECM rat model showed numerous clinical and histopathological features similar to Human CM and appears to be a promising model to achieve further understanding the CM pathophysiology in Humans and to evaluate the activity of specific antimalarial drugs in avoiding/limiting cerebral damages from malaria.

  17. 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

  18. Young Sprague Dawley rats infected by Plasmodium berghei: A relevant experimental model to study cerebral malaria.

    Science.gov (United States)

    Keita Alassane, Sokhna; Nicolau-Travers, Marie-Laure; Menard, Sandie; Andreoletti, Olivier; Cambus, Jean-Pierre; Gaudre, Noémie; Wlodarczyk, Myriam; Blanchard, Nicolas; Berry, Antoine; Abbes, Sarah; Colongo, David; Faye, Babacar; Augereau, Jean-Michel; Lacroux, Caroline; Iriart, Xavier; Benoit-Vical, Françoise

    2017-01-01

    Cerebral malaria (CM) is the most severe manifestation of human malaria yet is still poorly understood. Mouse models have been developed to address the subject. However, their relevance to mimic human pathogenesis is largely debated. Here we study an alternative cerebral malaria model with an experimental Plasmodium berghei Keyberg 173 (K173) infection in Sprague Dawley rats. As in Human, not all infected subjects showed cerebral malaria, with 45% of the rats exhibiting Experimental Cerebral Malaria (ECM) symptoms while the majority (55%) of the remaining rats developed severe anemia and hyperparasitemia (NoECM). These results allow, within the same population, a comparison of the noxious effects of the infection between ECM and severe malaria without ECM. Among the ECM rats, 77.8% died between day 5 and day 12 post-infection, while the remaining rats were spontaneously cured of neurological signs within 24-48 hours. The clinical ECM signs observed were paresis quickly evolving to limb paralysis, global paralysis associated with respiratory distress, and coma. The red blood cell (RBC) count remained normal but a drastic decrease of platelet count and an increase of white blood cell numbers were noted. ECM rats also showed a decrease of glucose and total CO2 levels and an increase of creatinine levels compared to control rats or rats with no ECM. Assessment of the blood-brain barrier revealed loss of integrity, and interestingly histopathological analysis highlighted cyto-adherence and sequestration of infected RBCs in brain vessels from ECM rats only. Overall, this ECM rat model showed numerous clinical and histopathological features similar to Human CM and appears to be a promising model to achieve further understanding the CM pathophysiology in Humans and to evaluate the activity of specific antimalarial drugs in avoiding/limiting cerebral damages from malaria.

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

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    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.

  20. Aerosolized avian influenza virus by laboratory manipulations

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    Li Zhiping

    2012-08-01

    Full Text Available Abstract Background Avian H5N1 influenza viruses present a challenge in the laboratory environment, as they are difficult to collect from the air due to their small size and relatively low concentration. In an effort to generate effective methods of H5N1 air removal and ensure the safety of laboratory personnel, this study was designed to investigate the characteristics of aerosolized H5N1 produced by laboratory manipulations during research studies. Results Normal laboratory procedures used to process the influenza virus were carried out independently and the amount of virus polluting the on-site atmosphere was measured. In particular, zootomy, grinding, centrifugation, pipetting, magnetic stirring, egg inoculation, and experimental zoogenetic infection were performed. In addition, common accidents associated with each process were simulated, including breaking glass containers, syringe injection of influenza virus solution, and rupturing of centrifuge tubes. A micro-cluster sampling ambient air pollution collection device was used to collect air samples. The collected viruses were tested for activity by measuring their ability to induce hemagglutination with chicken red blood cells and to propagate in chicken embryos after direct inoculation, the latter being detected by reverse-transcription PCR and HA test. The results showed that the air samples from the normal centrifugal group and the negative-control group were negative, while all other groups were positive for H5N1. Conclusions Our findings suggest that there are numerous sources of aerosols in laboratory operations involving H5N1. Thus, laboratory personnel should be aware of the exposure risk that accompanies routine procedures involved in H5N1 processing and take proactive measures to prevent accidental infection and decrease the risk of virus aerosol leakage beyond the laboratory.

  1. Efficiency of the oral, intramuscular and subcutaneous routes for the experimental infection of hamster and sheep with Schistosoma bovis.

    Science.gov (United States)

    Oleaga, Ana; Ramajo, Vicente

    2004-09-20

    The percutaneous administration of cercariae is the usual method for experimental infections with Schistosoma bovis. These procedures are laborious and have important inconveniences when working with a large number of animals, especially if they are ruminants. In the present study, the efficiency of the oral, intramuscular and subcutaneous routes are evaluated by comparison with the percutaneous route in experimental infections with S. bovis. The infections developed in hamsters and sheep were evaluated taking as a basis the parasite burden, the concentrations of eggs in tissues and the levels of anti-Schistosoma antibodies. The oral infection failed in both hamsters and sheep. The administration of the cercariae by the intramuscular route was effective in sheep, developing infections of intensity similar to that of the infections acquired percutaneously. In hamsters, on the contrary, although all the animals developed the infection, they were very little intense. The injection of the cercariae by the subcutaneous route induces acceptable infections in hamsters and can also be an alternative route to percutaneous exposure. The levels of the anti-Schistosoma bovis antibodies detected in hamster and sheep were proportional to the number of worms present, which shows that the humoral response is a good indicator of the intensity of the infections. It can be concluded that the intramuscular route is a good alternative to the percutaneous route for experimental infections of sheep with S. bovis. Likewise, the subcutaneous route can also substitute, with some advantages, the percutaneous infections in hamsters.

  2. MiR-34b-5p Suppresses Melanoma Differentiation-Associated Gene 5 (MDA5) Signaling Pathway to Promote Avian Leukosis Virus Subgroup J (ALV-J)-Infected Cells Proliferaction and ALV-J Replication.

    Science.gov (United States)

    Li, Zhenhui; Luo, Qingbin; Xu, Haiping; Zheng, Ming; Abdalla, Bahareldin Ali; Feng, Min; Cai, Bolin; Zhang, Xiaocui; Nie, Qinghua; Zhang, Xiquan

    2017-01-01

    Avian leukosis virus subgroup J (ALV-J) is an oncogenic retrovirus that has a similar replication cycle to multiple viruses and therefore can be used as a model system for viral entry into host cells. However, there are few reports on the genes or microRNAs (miRNAs) that are responsible for the replication of ALV-J. Our previous miRNA and RNA sequencing data showed that the expression of miR-34b-5p was significantly upregulated in ALV-J-infected chicken spleens compared to non-infected chicken spleens, but melanoma differentiation-associated gene 5 (MDA5) had the opposite expression pattern. In this study, a dual-luciferase reporter assay showed that MDA5 is a direct target of miR-34b-5p. In vitro, overexpression of miR-34b-5p accelerated the proliferation of ALV-J-infected cells by inducing the progression from G2 to S phase and it promoted cell migration. Ectopic expression of MDA5 inhibited ALV-J-infected cell proliferation, the cell cycle and cell migration, and knockdown of MDA5 promoted proliferation, the cell cycle and migration. In addition, during ALV-J infections, MDA5 can detect virus invasion and it triggers the MDA5 signaling pathway. MDA5 overexpression can activate the MDA5 signaling pathway, and thus it can inhibit the mRNA and protein expression of the ALV-J env gene and it can suppress virion secretion. In contrast, in response to the knockdown of MDA5 by small interfering RNA (siRNA) or an miR-34b-5p mimic, genes in the MDA5 signaling pathway were significantly downregulated (P J env and the sample-to-positive ratio of virion in the supernatants were increased. This indicates that miR-34b-5p is able to trigger the MDA5 signaling pathway and affect ALV-J infections. Together, these results suggest that miR-34b-5p targets MDA5 to accelerate the proliferation and migration of ALV-J-infected cells, and it promotes ALV-J replication, via the MDA5 signaling pathway.

  3. Molecular evolution of GB virus B hepatitis virus during acute resolving and persistent infections in experimentally infected tamarins

    DEFF Research Database (Denmark)

    Takikawa, Shingo; Engle, Ronald E; Faulk, Kristina N

    2010-01-01

    GB virus B (GBV-B) causes acute hepatitis in experimentally infected tamarins. We compared evolutionary features in acute resolving and persistent GBV-B infection. We detected no evidence of evolution in four animals with clearance during weeks 9-12, whereas three animals with clearance during......(-3) substitutions per site year(-1) during weeks 1-52 and 53-104, respectively. Thus, there was a significant decrease in evolution over time, as found for hepatitis C virus. The rate of non-synonymous substitution per non-synonymous site compared with that of synonymous substitution per synonymous site decreased...... weeks 13-26 had several substitutions in their polyprotein sequence. A single tamarin had long-term GBV-B viraemia; analysis of virus recovered at weeks 2, 5, 12, 20, 26, 52 and 104 demonstrated that mutations accumulated over time. Overall, the amino acid substitution rate was 3.5x10(-3) and 1.1x10...

  4. Experimental Ascaris suum infection in the pig: worm population kinetics following single inoculations with three doses of infective eggs.

    Science.gov (United States)

    Roepstorff, A; Eriksen, L; Slotved, H C; Nansen, P

    1997-10-01

    To study population kinetics during primary Ascaris suum infections, 3 groups of 52 pigs each were inoculated with 100, 1000, or 10,000 infective eggs. In all groups, the majority of larvae was found in the liver on day 3 post inoculation (p.i.) and in the lungs on day 7 p.i. Liver white spots, caused by migrating larvae, were most numerous at day 7 p.i., whereafter they gradually healed, and only low numbers of granulation-tissue type white spots and lymphonodular white spots persisted at days 21-56 p.i. Independent of dose level, 47-58% of the inoculated eggs were recovered as larvae in the small intestine on day 10 p.i., but most larvae were eliminated at days 17-21 p.i. This elimination started earlier and removed a higher percentage of the worms with increasing inoculation dose, resulting in small strongly aggregated worm populations by day 28 p.i. (k of the negative binomial distribution was low: 0.2-0.4) without significant differences between groups. Thus, overdispersion, which is a characteristic of both porcine and human ascarosis, is found here under experimental conditions where aggregation factors like host behaviour, transmission rate, host status etc have been partly or totally controlled.

  5. 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.

  6. Buparvaquone is active against Neospora caninum in vitro and in experimentally infected mice

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    Joachim Müller

    2015-04-01

    Full Text Available The naphthoquinone buparvaquone is currently the only drug used against theileriosis. Here, the effects of buparvaquone were investigated in vitro and in an experimental mouse model for Neospora caninum infection. In 4-day proliferation assays, buparvaquone efficiently inhibited N. caninum tachyzoite replication (IC50 = 4.9 nM; IC100 = 100 nM. However, in the long term tachyzoites adapted and resumed proliferation in the presence of 100 nM buparvaquone after 20 days of cultivation. Parasiticidal activity was noted after 9 days of culture in 0.5 µM or 6 days in 1 µM buparvaquone. TEM of N. caninum infected fibroblasts treated with 1 µM buparvaquone showed that the drug acted rather slowly, and ultrastructural changes were evident only after 3–5 days of treatment, including severe alterations in the parasite cytoplasm, changes in the composition of the parasitophorous vacuole matrix and a diminished integrity of the vacuole membrane. Treatment of N. caninum infected mice with buparvaquone (100 mg/kg either by intraperitoneal injection or gavage prevented neosporosis symptoms in 4 out of 6 mice in the intraperitoneally treated group, and in 6 out of 7 mice in the group receiving oral treatment. In the corresponding controls, all 6 mice injected intraperitoneally with corn oil alone died of acute neosporosis, and 4 out of 6 mice died in the orally treated control group. Assessment of infection intensities in the treatment groups showed that, compared to the drug treated groups, the controls showed a significantly higher parasite load in the lungs while cerebral parasite load was higher in the buparvaquone-treated groups. Thus, although buparvaquone did not eliminate the parasites infecting the CNS, the drug represents an interesting lead with the potential to eliminate, or at least diminish, fetal infection during pregnancy.

  7. An experimental ovine Theileriosis: The effect of Theileria lestoquardi infection on cardiovascular system in sheep.

    Science.gov (United States)

    Yaghfoori, Saeed; Razmi, Gholam Reza; Mohri, Mehrdad; Razavizadeh, Ali Reza Taghavi; Movassaghi, Ahmad Reza

    2016-09-01

    The malignant ovine theileriosis is caused by Theileria lestoquardi, which is highly pathogenic in sheep. Theileriosis involves different organs in ruminants, but the effect of the disease on the cardiovascular system is unclear. To understand the pathogenesis of T. lestoquardi on the cardiovascular system, Baluchi breed sheep were infected with the mentioned parasite by releasing unfed adults of Hyalomma anatolicum anatolicum, which were infected with T. lestoquardi. The infected sheep were clinically examined on days 0, 2, 5, 7, 10, 12, 14, 17, and 21, and the blood samples were collected for biochemical parameters measurement. At termination of the experiment, the infected sheep were euthanized and pathological examinations of heart tissue were conducted. During experimental infection of sheep with T. lestoquardi, activities of cardiac troponin I (cTnI), lactate dehydrogenase, and aspartate aminotransferase, were significantly increased (P˂0.05), while a conspicuous decrease (P˂0.05) was observed in creatine phosphokinase activities. Alterations made in biochemical factors almost coincided with the presence of piroplasm in the blood and schizont in lymph nodes. Maximum and minimum of parasitemia in the sheep stood between 3.3% and 0.28%, respectively. In addition, electrocardiography revealed sinus tachycardia, sinus arrhythmia, sino-atrial block and ST-elevation, atrial premature beat, and alteration in QRS and in T waves' amplitude. Heart histopathological examination showed hyperemia, infiltration of mononuclear inflammatory cells into interstitial tissue, endocarditis, and focal necrosis of cardiac muscle cells. In addition, in one of the sheep, definite occurrence of infarction was observed. The results indicate that T. lestoquardi infection has devastating pathological impacts on the cardiovascular system of sheep. Furthermore, measurement of the cTnI amount is a useful biochemical factor for diagnosis and for better understanding of the severity and

  8. Buparvaquone is active against Neospora caninum in vitro and in experimentally infected mice

    Science.gov (United States)

    Müller, Joachim; Aguado-Martinez, Adriana; Manser, Vera; Balmer, Vreni; Winzer, Pablo; Ritler, Dominic; Hostettler, Isabel; Arranz-Solís, David; Ortega-Mora, Luis; Hemphill, Andrew

    2015-01-01

    The naphthoquinone buparvaquone is currently the only drug used against theileriosis. Here, the effects of buparvaquone were investigated in vitro and in an experimental mouse model for Neospora caninum infection. In 4-day proliferation assays, buparvaquone efficiently inhibited N. caninum tachyzoite replication (IC50 = 4.9 nM; IC100 = 100 nM). However, in the long term tachyzoites adapted and resumed proliferation in the presence of 100 nM buparvaquone after 20 days of cultivation. Parasiticidal activity was noted after 9 days of culture in 0.5 µM or 6 days in 1 µM buparvaquone. TEM of N. caninum infected fibroblasts treated with 1 µM buparvaquone showed that the drug acted rather slowly, and ultrastructural changes were evident only after 3–5 days of treatment, including severe alterations in the parasite cytoplasm, changes in the composition of the parasitophorous vacuole matrix and a diminished integrity of the vacuole membrane. Treatment of N. caninum infected mice with buparvaquone (100 mg/kg) either by intraperitoneal injection or gavage prevented neosporosis symptoms in 4 out of 6 mice in the intraperitoneally treated group, and in 6 out of 7 mice in the group receiving oral treatment. In the corresponding controls, all 6 mice injected intraperitoneally with corn oil alone died of acute neosporosis, and 4 out of 6 mice died in the orally treated control group. Assessment of infection intensities in the treatment groups showed that, compared to the drug treated groups, the controls showed a significantly higher parasite load in the lungs while cerebral parasite load was higher in the buparvaquone-treated groups. Thus, although buparvaquone did not eliminate the parasites infecting the CNS, the drug represents an interesting lead with the potential to eliminate, or at least diminish, fetal infection during pregnancy. PMID:25941626

  9. Experimental infection of rabbits with bovine viral diarrhoea virus by a natural route of exposure

    Science.gov (United States)

    2014-01-01

    Bovine viral diarrhoea virus (BVDV) is an important pathogen of cattle that can naturally infect a wide range of even-toed ungulates. Non-bovine hosts may represent reservoirs for the virus that have the potential to hamper BVDV eradication programs usually focused on cattle. Rabbits are very abundant in countries such as the United Kingdom or Australia and are often living on or near livestock pastures. Earlier reports indicated that rabbits can propagate BVDV upon intravenous exposure and that natural infection of rabbits with BVDV may occur but experimental proof of infection of rabbits by a natural route is lacking. Therefore, New Zealand White rabbits were exposed to a Scottish BVDV field strain intravenously, oro-nasally and by contaminating their hay with virus. None of the animals showed any clinical signs. However, the lymphoid organs from animals sacrificed at day five after exposure showed histological changes typical of transient infection with pestivirus. Most organ samples and some buffy coat samples were virus positive at day five but saliva samples remained negative. Development of antibodies was observed in all intravenously challenged animals, in all of the nebulised group and in four of six animals exposed to contaminated hay. To our knowledge this is the first report of BVDV propagation in a species other than ruminants or pigs after exposure to the virus by a natural route. However, to assess the role of rabbits as a potential reservoir for BVDV it remains to be determined whether persistent infection caused by intra-uterine infection is possible and whether BVDV is circulating in wild rabbit populations. PMID:24690167

  10. 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.

  11. Pathophysiological variability of different genotypes of human Blastocystis hominis Egyptian isolates in experimentally infected rats.

    Science.gov (United States)

    Hussein, Eman M; Hussein, Abdalla M; Eida, Mohamed M; Atwa, Maha M

    2008-04-01

    The genotyping of Blastocystis hominis clinical isolates obtained from 28 gastrointestinal symptomatic patients and 16 asymptomatic individuals were identified by polymerase chain reaction using sequenced-tagged site (STS) primers. Then, pathophysiological variability between different B. hominis genotypes was evaluated in experimentally infected rats. Only four B. hominis subtypes (1, 2, 3, and 4) were detected (18.2%, 9.1%, 54.5%, and 18.2%, respectively) in human isolates. In symptomatic isolates, subtypes 1, 3, and 4 were detected in 8 (28.6%), 16 (57.1%), and 4 (14.3%) patients, respectively. In asymptomatic isolates, subtypes 2, 3, and 4 were identified in 4 (25%), 8 (50%), and 4 (25%), respectively. Subtype 3 was the commonest in humans. Different degrees of pathological changes were found among infected rats by symptomatic subtypes compared with asymptomatic subtypes. The moderate and severe degrees of pathological changes were found only in symptomatic subtypes infected rats while mild degree was found only in asymptomatic subtypes infected rats. Only subtype 1 induced mortality rate with 25% among infected rats. On evaluation of the intestinal cell permeability in the Ussing chamber, a prominent increase in short circuit current (DeltaIsc) was found in symptomatic subtype 1 compared to symptomatic subtypes 3 and 4 infected rats. Minimal effects were found in the asymptomatic and control groups. The results proved that subtype 1 was clinically and statistically highly relevant to the pathogenicity of B. hominis while subtype 2 was irrelevant. Also, the results suggest the presence of pathogenic and nonpathogenic strains among subtypes 3 and 4.

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

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    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

  13. Response of Cytokines and Hydrogen Peroxide to Sporothrix schenckii Exoantigen in Systemic Experimental Infection.

    Science.gov (United States)

    Maia, Danielle Cardoso Geraldo; Gonçalves, Amanda Costa; Ferreira, Lucas Souza; Manente, Francine Alessandra; Portuondo, Deivys Leandro; Vellosa, José Carlos Rebuglio; Polesi, Marisa Campos; Batista-Duharte, Alexander; Carlos, Iracilda Zeppone

    2016-04-01

    The response of hydrogen peroxide (H2O2) and cytokines during an experimental sporotrichosis in male Swiss mice was assessed over a period of 10 weeks by monitoring macrophage activation challenged with exoantigen (ExoAg) from the fungus Sporothrix schenckii. The studied endpoints were: H2O2 production, fungal burden at spleen, apoptosis in peritoneal macrophages, and IL-1β, IL-6, IL-2, IL-10 production. During the two first weeks of infection was observed low burden of yeast in spleen and high response of H2O2, IL-2, and IL-1β. The weeks of highest fungal burden (fourth-sixth) coincided with major apoptosis in peritoneal macrophages, normal production of IL-6 and lower production of H2O2, IL-2, and IL-1β, suggesting a role for these three last in the early control of infection. On the other hand, IL-1β (but not IL-6) was recovered since the sixth week, suggesting a possible role in the late phase of infection, contributing to the fungal clearance in conjunction with the specific mechanisms. The IL-10 was elevated until the sixth, principally in the second week. These results evidences that ExoAg is involved in the host immune modulation, influencing the S. Schenckii virulence, and its role is related with the time of the infection in the model used.

  14. 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.

  15. 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.

  16. Determination of IgG avidity in BALB/c mice experimentally infected with Toxocara canis.

    Science.gov (United States)

    Schoenardie, Elizandra Roselaine; Scaini, Carlos James; Avila, Luciana Farias da Costa de; Sperotto, Rita Leal; Borsuk, Sibele; Felicetti, Cristine Dias Pires; Pepe, Michele; Berne, Maria Elisabeth Aires

    2014-01-01

    Toxocariasis is a zoonotic disease in that IgM titers can remain high for long periods making difficult to determine the stage of the disease. The aim of this study is to investigate the applicability of indirect ELISA, associated with urea, to discriminate between the acute and chronic toxocariasis. IgG avidity was evaluated in 25 BALB/c mice experimentally infected with 1000 Toxocara canis eggs. Blood samples were collected, and sera treated with 6 M urea and assayed by ELISA every two weeks. The percent IgG avidity was determined using the mean absorbance of sera treated with urea, divided by the mean absorbance of untreated sera. In the first 15 days post-inoculation, was observed a low percentage, between 7.25 and 27.5%, IgG avidity, characteristic of an acute infection. After 60 days of infection, all the mice showed between 31.4 and 58% IgG avidity, indicating a chronic infection.

  17. Experimental Leishmania major infection suppresses HIV-1 DNA vaccine induced cellular immune response.

    Science.gov (United States)

    Robinson, Tara M; Nelson, Robin; Artis, David; Scott, Phillip; Boyer, Jean D

    2004-01-01

    The AIDS epidemic in the developing world represents a major global crisis and an effective vaccine is imperative. However, many parasites are common in developing countries and can result in a state of chronic immune activation that is polarized towards a Th2 profile and which can potentially impair responses to vaccines or other infectious challenges. In this study we demonstrate that experimental Leishmania major infection of BALB/c mice inhibits responses to a DNA-based HIV-1 gag vaccine. L. major infection in BALB/c results in a polarized Th2 immune response. In this study naïve BALB/c mice immunized with the HIV-1 gag DNA vaccine mounted a cellular immune response against the vaccine antigen, HIV-1 gag. CD8+ T lymphocytes were able to respond in vitro to HIV-1 gag stimulation and secrete interferon (IFN)-gamma. However, L. major-infected, vaccinated BALB/c mice had a significantly reduced number of IFN-gamma-producing CD8+ T cells following in vitro stimulation with gag antigen. These data suggest that parasitic infection, which results in a Th2 profile, reduces the efficacy of DNA vaccines that are designed to induce antiviral CD8+ T cell responses. Copyright 2004 S. Karger AG, Basel

  18. Allergy skin test responses during experimental infection with respiratory syncytial virus.

    Science.gov (United States)

    Skoner, David P; Gentile, Deborah A; Angelini, Betty; Doyle, William J

    2006-06-01

    Allergy skin testing is one of the most frequently performed physician office procedures. Many factors can affect the results of those tests, including the well-defined suppressive effect of systemic antihistamines. False-positive allergen skin test results are known to occur; however, contributing factors are not well understood. To determine whether a viral upper respiratory tract infection affects allergy skin test responsiveness. We performed skin tests with histamine and a panel of geographically relevant inhalant allergens on 16 adults before and 3, 6, and 21 days after experimental exposure to respiratory syncytial virus (RSV), a virus that causes signs and symptoms of a cold. The RSV exposure, with and without documented infection, caused increased wheal and flare areas to histamine and allergen and de novo positive allergen test responses in individuals with no measurable responses at baseline. These were noted as late as 21 days after RSV exposure and may be consistent with mediation by up-regulated neurogenic inflammation during RSV infection. These results may have implications for explaining the cause of such well-known complications of RSV infection as otitis media, bronchiolitis, and asthmatic exacerbation.

  19. The Effect of Marshallagia marshalli on Serum Gastrin Concentrations in Experimentally Infected Lambs.

    Science.gov (United States)

    Moradpour, Nona; Borji, Hassan; Razmi, Gholamreza; Maleki, Mohsen; Kazemi, Hossein

    2016-08-01

    :  Because there appeared to be no data available on serum gastrin concentrations in animals infected with Marshallagia marshalli, and considering the high prevalence of this parasite in livestock throughout many countries, we decided to perform research in the field using experimental infection. After surgical implantation of abomasal cannula into 10 male Baluchi sheep, each animal was orally infected with 5,000 M. marshalli larvae. Serum gastrin concentrations and abomasal pH were measured with a human ELISA kit and a PHM LE438 standard pH electrode, respectively. According to the results obtained from the study, serum gastrin increased after 14 and 21 days post-infection (dpi), while abomasal pH increased after 7 dpi and reached a maximal value 16 dpi. The increase in serum gastrin concentration was revealed 6 days after elevation in abomasal pH, which could be the result of reduced acid secretion. Generally, the present study pointed out that a limited number of M. marshalli could increase serum gastrin concentrations.

  20. Implications for a regulated replication of Borna disease virus in brains of experimentally infected Lewis rats.

    Science.gov (United States)

    Porombka, Doris; Baumgärtner, Wolfgang; Eickmann, Markus; Herden, Christiane

    2008-04-01

    The neurotropic Borna disease virus (BDV) causes typically a persistent virus infection of the central nervous system. In order to investigate whether an adapted virus replication contributes to BDV persistence in vivo, a fast and reliable real-time RT-PCR assay was constructed to quantify the amounts of leader-containing (leBDV) as a marker for virus replication, genomic (vBDV) and nucleoprotein-(BDV-N +ssRNA)-specific RNA. Therefore, leBDV, vBDV and BDV-N +ssRNA values were determined in experimentally infected Lewis rats between 14 and 90 days post infection (dpi). Surprisingly low leBDV values were found compared to vBDV and the abundantly expressed BDV-N transcripts. vBDV multiplied only in the acute phase of infection followed by constant expression until 90 dpi. Ratios of vBDV to leBDV were 401:1 at 14 dpi and diminished to 209:1 at 90 dpi, indicating a regulated co-expression of replicative intermediates as a potential prerequisite for viral persistence.

  1. Susceptibility to Yersinia pestis experimental infection in wild Rattus rattus, reservoir of plague in Madagascar.

    Science.gov (United States)

    Tollenaere, C; Rahalison, L; Ranjalahy, M; Duplantier, J-M; Rahelinirina, S; Telfer, S; Brouat, C

    2010-06-01

    In Madagascar, the black rat, Rattus rattus, is the main reservoir of plague (Yersinia pestis infection), a disease still responsible for hundreds of cases each year in this country. This study used experimental plague challenge to assess susceptibility in wild-caught rats to better understand how R. rattus can act as a plague reservoir. An important difference in plague resistance between rat populations from the plague focus (central highlands) and those from the plague-free zone (low altitude area) was confirmed to be a widespread phenomenon. In rats from the plague focus, we observed that sex influenced plague susceptibility, with males slightly more resistant than females. Other individual factors investigated (weight and habitat of sampling) did not affect plague resistance. When infected at high bacterial dose (more than 10⁵ bacteria injected), rats from the plague focus died mainly within 3-5 days and produced specific antibodies, whereas after low-dose infection (plague resistance level and the course of infection in the black rat would contribute to a better understanding of plague circulation in Madagascar.

  2. Efficacy of clorsulon for the treatment of experimentally induced infections of Fasciola hepatica in goats.

    Science.gov (United States)

    Sundlof, S F; Bliss, E L; Greiner, E C; Tran, T Q; Wertenberger, M A

    1991-01-01

    A dose titration study was undertaken to determine the efficacy of clorsulon against the adult stage of Fasciola hepatica in goats. Thirty-nine goats were experimentally infected with metacercariae of F hepatica. At 14 weeks after infection, each goat was assigned randomly to 1 of 5 groups. Goats in groups 1 to 4 received a single oral administration of clorsulon at dosages of 3.5, 7, 11, and 15 mg/kg of body weight, respectively. The fifth group of goats (control group) was infected with F hepatica, but were not treated with clorsulon. Postmortem examination of goats at 3 weeks after treatment revealed mean reductions in numbers of flukes of 83, 98, 99, and 100% for groups 1 to 4, respectively. Mean percentage of reduction in eggs following treatment of groups was 82, 98, 100, and 100%, respectively. The clinical effects of clorsulon in 24 goats that were not infected with F hepatica were studied. Goats in groups 1 to 3 received a single oral administration of clorsulon at dosages of 7, 21, and 35 mg/kg, respectively, every other day for a total of 3 doses/goat. Group-4 goats (control group) received a vehicle placebo. Goats in group 3 were subject to postmortem examination at 14 days after dosing. Abnormal signs or lesions that could be attributed to clorsulon were not found in any goat.

  3. 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

  4. 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

  5. Modelling the innate immune response against avian influenza virus in chicken

    NARCIS (Netherlands)

    Hagenaars, T.J.; Fischer, E.A.J.; Jansen, C.A.; Rebel, J.M.J.; Spekreijse, D.; Vervelde, L.; Backer, J.A.; Jong, de M.C.M.; Koets, A.P.

    2016-01-01

    At present there is limited understanding of the host immune response to (low pathogenic) avian influenza virus infections in poultry. Here we develop a mathematical model for the innate immune response to avian influenza virus in chicken lung, describing the dynamics of viral load,

  6. Susceptibility of various parental lines of commercial white leghorn layers to infection with a naturally occurring recombinant avian leukosis virus containing subgroup B envelope and subgroup J long terminal repeat.

    Science.gov (United States)

    Mays, Jody K; Pandiri, Arun R; Fadly, Aly M

    2006-09-01

    Chickens from seven different parental lines of commercial White Leghorn layer flocks from three independent breeders were inoculated with a naturally occurring avian leukosis virus (ALV) containing an ALV-B envelope and an ALV-J long terminal repeat (LTR) termed ALV-B/J. Additional groups of chickens from the same seven parental lines were inoculated with ALV-B. Chickens were tested for ALV viremia and antibody at 0, 4, 8, 16, and 32 wk postinfection. Chickens from all parental lines studied were susceptible to infection with ALV-B with 40%-100% of inoculated chickens positive for ALV at hatch following embryo infection. Similarly, infection of egg layer flocks with the ALV-B/J recombinant virus at 8 days of embryonation induced tolerance to ALV with 86%-100% of the chickens viremic, 40%-75% of the chickens shedding virus, and only 2/125 (2%) of the chickens producing serum-neutralizing antibodies against homologous ALV-B/J recombinant virus at 32 wk postinfection. In contrast, when infected with the ALV-B/J recombinant virus at hatch, 33%-82% of the chickens were viremic, 28%-47% shed virus, and 0%-56% produced serum-neutralizing antibodies against homologous ALV-B/J recombinant virus at 32 wk postinfection. Infection with the ALV-B/J recombinant virus at embryonation and at hatch induced predominately lymphoid leukosis (LL), along with other common ALV neoplasms, including erythroblastosis, osteopetrosis, nephroblastomas, and rhabdosarcomas. No incidence of myeloid leukosis (ML) was observed in any of the commercial White Leghorn egg layer flocks infected with ALV-B/J in the present study. Data suggest that the parental line of commercial layers may influence development of ALV-B/J-induced viremia and antibody, but not tumor type. Differences in type of tumors noted in the present study and those noted in the field case where the ALV-B/J was first isolated may be attributed to differences in the genetics of the commercial layer flock in which ML was first

  7. Species-specific escape of Plasmodium sporozoites from oocysts of avian, rodent, and human malarial parasites.

    Science.gov (United States)

    Orfano, Alessandra S; Nacif-Pimenta, Rafael; Duarte, Ana P M; Villegas, Luis M; Rodrigues, Nilton B; Pinto, Luciana C; Campos, Keillen M M; Pinilla, Yudi T; Chaves, Bárbara; Barbosa Guerra, Maria G V; Monteiro, Wuelton M; Smith, Ryan C; Molina-Cruz, Alvaro; Lacerda, Marcus V G; Secundino, Nágila F C; Jacobs-Lorena, Marcelo; Barillas-Mury, Carolina; Pimenta, Paulo F P

    2016-08-02

    Malaria is transmitted when an infected mosquito delivers Plasmodium sporozoites into a vertebrate host. There are many species of Plasmodium and, in general, the infection is host-specific. For example, Plasmodium gallinaceum is an avian parasite, while Plasmodium berghei infects mice. These two parasites have been extensively used as experimental models of malaria transmission. Plasmodium falciparum and Plasmodium vivax are the most important agents of human malaria, a life-threatening disease of global importance. To complete their life cycle, Plasmodium parasites must traverse the mosquito midgut and form an oocyst that will divide continuously. Mature oocysts release thousands of sporozoites into the mosquito haemolymph that must reach the salivary gland to infect a new vertebrate host. The current understanding of the biology of oocyst formation and sporozoite release is mostly based on experimental infections with P. berghei, and the conclusions are generalized to other Plasmodium species that infect humans without further morphological analyses. Here, it is described the microanatomy of sporozoite escape from oocysts of four Plasmodium species: the two laboratory models, P. gallinaceum and P. berghei, and the two main species that cause malaria in humans, P. vivax and P. falciparum. It was found that sporozoites have species-specific mechanisms of escape from the oocyst. The two model species of Plasmodium had a common mechanism, in which the oocyst wall breaks down before sporozoites emerge. In contrast, P. vivax and P. falciparum sporozoites show a dynamic escape mechanism from the oocyst via polarized propulsion. This study demonstrated that Plasmodium species do not share a common mechanism of sporozoite escape, as previously thought, but show complex and species-specific mechanisms. In addition, the knowledge of this phenomenon in human Plasmodium can facilitate transmission-blocking studies and not those ones only based on the murine and avian models.

  8. Experimental therapeutic studies of Solanum aculeastrum Dunal. on Leishmania major infection in BALB/c mice.

    Science.gov (United States)

    Laban, Linet T; Anjili, Christopher O; Mutiso, Joshua M; Ingonga, Johnstone; Kiige, Samuel G; Ngedzo, Mgala M; Gicheru, Michael M

    2015-01-01

    Solanum acueastrum Dunal. has been shown to have some chemotherapeutic value. Leaf and berry water and methanol compounds of S. acueastrum were evaluated for possible antileishmanial activity In vivo on BALB/c mice and in vitro against Leishmania major promastigotes, amastigotes and vero cells. Dry S. aculeastrum berry and leaf material were extracted in methanol and water. L. major parasites were exposed to different concentrations of S. aculeastrum fruit and leaf compounds and the IC50 on the promastigotes, percentage of infection rate of macrophages by amastigotes and the toxicological effect on vero cells were determined. BALB/c mice were infected subcutaneously with 1×10(6) promastigotes and kept for four weeks to allow for disease establishment. Infected mice were treated with fruit and leaf methanolic and water compounds, amphotericin B (AmB), and sterile phosphate buffered saline (PBS). Fruit methanol compound was most effective in inhibiting the growth of promastigotes with IC5078.62 μg/ml. Fruit water compound showed the best activity in inhibiting infection of macrophages by amastigotes. Fruit methanol compound was more toxic at Ld50=8.06 mg/ml to vero cells than amphotericin B. Analysis of variance computation indicated statistically significant difference in lesion sizes between experimental and control mice groups (P=0.0001). Splenic impression smears ANOVA indicated a highly significant difference in parasitic numbers between the experimental and the control groups (P=0.0001). The results demonstrate that compounds from S. aculeastrum have potential anti-leishmanial activities and the medicinal use of the plant poses considerable toxicity against dividing vero cells.

  9. 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.

  10. Comparison of Abortion and Infection after Experimental Challenge of Pregnant Bison and Cattle with Brucella abortus Strain 2308▿

    Science.gov (United States)

    Olsen, S. C.; Johnson, C.

    2011-01-01

    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 during midgestation. The incidence of abortion, fetal infection, uterine or mammary infection, or infection in maternal tissues after experimental challenge was greater (P abort, the time between experimental challenge and abortion was shorter (P abortion did not differ (P > 0.05) between cattle and bison. The results of our study suggest that naive bison and cattle have similarities and differences after experimental exposure to a virulent B. abortus strain. Although our data suggest that bison may be more susceptible to infection with Brucella, some pathogenic characteristics of brucellosis were similar between bison and cattle. PMID:21976222

  11. INVOLVEMENT OF BACTERICIDAL FACTORS FROM THROMBIN-STIMULATED PLATELETS IN CLEARANCE OF ADHERENT VIRIDANS STREPTOCOCCI IN EXPERIMENTAL INFECTIVE ENDOCARDITIS

    NARCIS (Netherlands)

    VANDERWERFF, J; ZAAT, SAJ; JOLDERSMA, W; HESS, J

    Platelets activated with thrombin release bactericidal factors. We studied the role of the susceptibility of viridans streptococci to these bactericidal factors in the development of infective endocarditis (IE). By using the experimental endocarditis rabbit model, the initial adherence and the

  12. Natural Schistosoma mansoni infection in Nectomys squamipes: histopathological and morphometric analysis in comparison to experimentally infected N. squamipes and C3H/He mice

    Directory of Open Access Journals (Sweden)

    Michele Costa-Silva

    2002-10-01

    Full Text Available Histopathologic and morphometric (area, perimeter, major and minor diameters analysis of hepatic granulomas isolated from twelve naturally infected Nectomys squamipes were compared to four experimentally infected ones and six C3H/He mice. Liver paraffin sections were stained for cells and extracellular matrix. Both groups of N. squamipes presented peculiar granulomas consisting predominantly of large macrophages, full of schistosome pigment, characterizing an exudative-macrophage granuloma type, smaller than the equivalent granuloma type in mouse. Naturally infected animals exhibited granulomas in different stages of development, including large number of involutional types. Morphometric analysis showed that all measurements were smaller in naturally infected animals than in other groups. The results demonstrated that both N. squamipes groups reproduced, with small variations, the hepatic granuloma aspects already described in cricetidium (Calomys callosus, showing a genetic tendency to set up strong macrophage responses and small granulomas. Unexpectedly, natural infection did not engender distinguished histopathological characteristics distinct from those derived from experimental single infection, showing changes predominantly secondary to the duration of infection. It appears that the variability of the inocula (and the number of infections? interfere more with the quantity than with the quality of the pathological changes, denoting some morpho-functional determinism in the response to schistosomal infection dependent on the animal species.

  13. Comparative efficacy of tulathromycin and tildipirosin for the treatment of experimental Mycoplasma bovis infection in calves

    OpenAIRE

    Bartram, David J.; Moyaert, Hilde; Vanimisetti, Bindu H.; Ramage, Clifford P.; Reddick, David; Stegemann, Michael R

    2016-01-01

    Abstract The objective of this negative controlled, blinded, randomised, parallel group study was to compare the efficacy of two injectable macrolide antimicrobials, tulathromycin and tildipirosin, administered by single subcutaneous injection at dose rates of 2.5 and 4.0 mg kg−1 bodyweight, respectively, in the treatment of an experimentally induced Mycoplasma bovis infection in calves. A total of 238 M. bovis‐negative calves were challenged on three consecutive days with M. bovis by endobro...

  14. Recovery of Dengue Viruses from Tissues of Experimentally Infected Rhesus Monkeys

    Science.gov (United States)

    Marchette, Nyven J.; Halstead, Scott B.; Nash, Donald R.; Stenhouse, Andrew C.

    1972-01-01

    A tissue explant culture technique for the recovery of dengue virus from experimentally infected monkey tissue is described and compared with tissue culture assay of tissue triturates and co-cultivation of trypsinized cells in cell cultures. The most efficient technique was one in which minced tissue was explanted in co-culture with dengue virus-susceptible LLC-MK2 monkey kidney cells. This technique shows promise of being useful for detection of virus in autopsy material from fatal dengue hemorrhagic fever cases. PMID:4627963

  15. The pathology of experimental Schistosoma curassoni infections in mice and hamsters.

    Science.gov (United States)

    Vercruysse, J; Fransen, J; Southgate, V R; Rollinson, D

    1986-11-01

    The histopathology of experimental Schistosoma curassoni infections in white mice and hamsters was studied. In mice, hepatic lesions were severe with characteristic extensive perilobular fibrosis and large perilobular granulomas throughout the parenchyma. Only a few granulomas were detected in the lung, small intestine, and rectum of mice. In hamsters, lesions in the liver were limited. Few granulomas were found but the giant cell reaction was pronounced. Lesions in the lung and small intestine were minimal. Many subserosal and submucosal epithelioid cell granulomas were in the colon and rectum of hamsters. Parasites were not detected in the bladder of either mice or hamsters.

  16. 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

  17. Longevity and composition of cellular immune responses following experimental Plasmodium falciparum malaria infection in humans.

    Directory of Open Access Journals (Sweden)

    Anne C Teirlinck

    2011-12-01

    Full Text Available Cellular responses to Plasmodium falciparum parasites, in particular interferon-gamma (IFNγ production, play an important role in anti-malarial immunity. However, clinical immunity to malaria develops slowly amongst naturally exposed populations, the dynamics of cellular responses in relation to exposure are difficult to study and data about the persistence of such responses are controversial. Here we assess the longevity and composition of cellular immune responses following experimental malaria infection in human volunteers. We conducted a longitudinal study of cellular immunological responses to sporozoites (PfSpz and asexual blood-stage (PfRBC malaria parasites in naïve human volunteers undergoing single (n = 5 or multiple (n = 10 experimental P. falciparum infections under highly controlled conditions. IFNγ and interleukin-2 (IL-2 responses following in vitro re-stimulation were measured by flow-cytometry prior to, during and more than one year post infection. We show that cellular responses to both PfSpz and PfRBC are induced and remain almost undiminished up to 14 months after even a single malaria episode. Remarkably, not only 'adaptive' but also 'innate' lymphocyte subsets contribute to the increased IFNγ response, including αβT cells, γδT cells and NK cells. Furthermore, results from depletion and autologous recombination experiments of lymphocyte subsets suggest that immunological memory for PfRBC is carried within both the αβT cells and γδT compartments. Indeed, the majority of cytokine producing T lymphocytes express an CD45RO(+ CD62L(- effector memory (EM phenotype both early and late post infection. Finally, we demonstrate that malaria infection induces and maintains polyfunctional (IFNγ(+IL-2(+ EM responses against both PfRBC and PfSpz, previously found to be associated with protection. These data demonstrate that cellular responses can be readily induced and are long-lived following infection with P

  18. Establishment of macrocyclic lactone resistant Dirofilaria immitis isolates in experimentally infected laboratory dogs.

    Science.gov (United States)

    Pulaski, Cassan N; Malone, John B; Bourguinat, Catherine; Prichard, Roger; Geary, Timothy; Ward, Danielle; Klei, Thomas R; Guidry, Ta