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Sample records for classical sheep scrapie

  1. Detection of prions in the faeces of sheep naturally infected with classical scrapie

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    Terry Linda A

    2011-05-01

    Full Text Available Abstract Classical scrapie is a naturally transmitted prion disease of sheep and goats. Contaminated environments may contribute to the spread of disease and evidence from animal models has implicated urine, blood, saliva, placenta and faeces as possible sources of the infection. Here we sought to determine whether sheep naturally infected with classical scrapie shed prions in their faeces. We used serial protein misfolding cyclic amplification (sPMCA along with two extraction methods to examine faeces from sheep during both the clinical and preclinical phases of the disease and showed amplification of PrPSc in 7 of 15 and 14 of 14 sheep respectively. However PrPSc was not amplified from the faeces of 25 sheep not exposed to scrapie. These data represent the first demonstration of prion shedding in faeces from a naturally infected host and thus a likely source of prion contamination in the environment.

  2. Classical scrapie prions are associated with peripheral blood monocytes and T-lymphocytes from naturally infected sheep

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    Classical scrapie is a transmissible spongiform encephalopathy that affects sheep and goats. As detected by enzyme-linked immunoassay, previous studies suggested scrapie prions in the blood of sheep might be associated with B lymphocytes but not with monocytes or T lymphocytes. The association of sc...

  3. Epidemiological characteristics of classical scrapie outbreaks in 30 sheep flocks in the United Kingdom.

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    K Marie McIntyre

    Full Text Available Most previous analyses of scrapie outbreaks have focused on flocks run by research institutes, which may not reflect the field situation. Within this study, we attempt to rectify this deficit by describing the epidemiological characteristics of 30 sheep flocks naturally-infected with classical scrapie, and by exploring possible underlying causes of variation in the characteristics between flocks, including flock-level prion protein (PrP genotype profile. In total, the study involved PrP genotype data for nearly 8600 animals and over 400 scrapie cases.We found that most scrapie cases were restricted to just two PrP genotypes (ARQ/VRQ and VRQ/VRQ, though two flocks had markedly different affected genotypes, despite having similar underlying genotype profiles to other flocks of the same breed; we identified differences amongst flocks in the age of cases of certain PrP genotypes; we found that the age-at-onset of clinical signs depended on peak incidence and flock type; we found evidence that purchasing infected animals is an important means of introducing scrapie to a flock; we found some evidence that flock-level PrP genotype profile and flock size account for variation in outbreak characteristics; identified seasonality in cases associated with lambing time in certain flocks; and we identified one case that was homozygous for phenylalanine at codon 141, a polymorphism associated with a very high risk of atypical scrapie, and 28 cases that were heterozygous at this codon.This paper presents the largest study to date on commercially-run sheep flocks naturally-infected with classical scrapie, involving 30 study flocks, more than 400 scrapie cases and over 8500 PrP genotypes. We show that some of the observed variation in epidemiological characteristics between farms is related to differences in their PrP genotype profile; although much remains unexplained and may instead be attributed to the stochastic nature of scrapie dynamics.

  4. Selective breeding for scrapie resistance in sheep

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    Cristina Santos Sotomaior

    2012-11-01

    Full Text Available It is well known that the susceptibility of sheep to scrapie is determined by the host’s prion protein gene (PRNP. PRNP polymorphisms at codons 136 (alanine, A/valine, V, 154 (histidine, H/arginine, R and 171 (glutamine, Q/histidine, H/arginine, R are the main determinants of sheep susceptibility/resistance to classical scrapie. There are four major variants of the wild-type ARQ allele: VRQ, AHQ, ARH and ARR. Breeding programs have been developed in the European Union and the USA to increase the frequency of the resistant ARR allele while decreasing the frequency of the susceptible VRQ allele in sheep populations. In Brazil, little PRNP genotyping data are available for sheep, and thus far, no controlled breeding scheme for scrapie has been implemented. This review will focus on important epidemiological aspects of scrapie and the use of genetic resistance as a tool in breeding programs to control the disease.

  5. Selective breeding for scrapie resistance in sheep

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    Cristina Santos Sotomaior; Fernanda Trentini Lopes Ribeiro; Rüdiger Daniel Ollhoff

    2012-01-01

    It is well known that the susceptibility of sheep to scrapie is determined by the host’s prion protein gene (PRNP). PRNP polymorphisms at codons 136 (alanine, A/valine, V), 154 (histidine, H/arginine, R) and 171 (glutamine, Q/histidine, H/arginine, R) are the main determinants of sheep susceptibility/resistance to classical scrapie. There are four major variants of the wild-type ARQ allele: VRQ, AHQ, ARH and ARR. Breeding programs have been developed in the European Union and the USA to incre...

  6. Proteinase K-resistant material in ARR/VRQ sheep brain affected with classical scrapie is composed mainly of VRQ prion protein.

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    Jacobs, J G; Bossers, A; Rezaei, H; van Keulen, L J M; McCutcheon, S; Sklaviadis, T; Lantier, I; Berthon, P; Lantier, F; van Zijderveld, F G; Langeveld, J P M

    2011-12-01

    Classical scrapie is a prion disease in sheep and goats. In sheep, susceptibility to disease is genetically influenced by single amino acid substitutions. Genetic breeding programs aimed at enrichment of arginine-171 (171R) prion protein (PrP), the so-called ARR allele, in the sheep population have been demonstrated to be effective in reducing the occurrence of classical scrapie in the field. Understanding the molecular basis for this reduced prevalence would serve the assessment of ARR adaptation. The prion formation mechanism and conversion of PrP from the normal form (PrP(C)) to the scrapie-associated form (PrP(Sc)) could play a key role in this process. Therefore, we investigated whether the ARR allele substantially contributes to scrapie prion formation in naturally infected heterozygous 171Q/R animals. Two methods were applied to brain tissue of 171Q/R heterozygous sheep with natural scrapie to determine the relative amount of the 171R PrP fraction in PrP(res), the proteinase K-resistant PrP(Sc) core. An antibody test differentiating between 171Q and 171R PrP fragments showed that PrP(res) was mostly composed of the 171Q allelotype. Furthermore, using a novel tool for prion research, endoproteinase Lys-C-digested PrP(res) yielded substantial amounts of a nonglycosylated and a monoglycosylated PrP fragment comprising codons 114 to 188. Following two-dimensional gel electrophoresis, only marginal amounts (<9%) of 171R PrP(res) were detected. Enhanced 171R(res) proteolytic susceptibility could be excluded. Thus, these data support a nearly zero contribution of 171R PrP in PrP(res) of 171R/Q field scrapie-infected animals. This is suggestive of a poor adaptation of classical scrapie to this resistance allele under these natural conditions.

  7. Protective effect of the AT137RQ and ARQK176 PrP alleles against classical scrapie in Sarda breed sheep

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    Vaccari, Gabriele; Scavia, Gaia; Sala, Marcello; Cosseddu, Gianmario; Chiappini, Barbara; Conte, Michela; Esposito, Elena; Lorenzetti, Raniero; Perfetti, Gabriella; Marconi, Paola; Scholl, Francesco; Barbaro, Katia; Bella, Antonino; Nonno, Romolo; Agrimi, Umberto

    2009-01-01

    The susceptibility of sheep to scrapie is under the control of the host’s prion protein (PrP) gene and is also influenced by the strain of the agent. PrP polymorphisms at codons 136 (A/V), 154 (R/H) and 171 (Q/R/H) are the main determinants of susceptibility/resistance of sheep to classical scrapie. They are combined in four main variants of the wild-type ARQ allele: VRQ, AHQ, ARH and ARR. Breeding programmes have been undertaken on this basis in the European Union and the USA to increase the frequency of the resistant ARR allele in sheep populations. Herein, we report the results of a multi-flock study showing the protective effect of polymorphisms other than those at codons 136, 154 and 171 in Sarda breed sheep. All ARQ/ARQ affected sheep (n = 154) and 378 negative ARQ/ARQ controls from four scrapie outbreaks were submitted to sequencing of the PrP gene. The distribution of variations other than those at the standard three codons, between scrapie cases and negative controls, was statistically different in all flocks. In particular, the AT137RQ and ARQK176 alleles showed a clear protective effect. This is the first study demonstrating a protective influence of alleles other than ARR under field conditions. If further investigations in other sheep breeds and with other scrapie sources confirm these findings, the availability of various protective alleles in breeding programmes of sheep for scrapie resistance could be useful in breeds with a low frequency of the ARR allele and would allow maintaining a wider variability of the PrP gene. PMID:19171116

  8. Genotyping and surveillance for scrapie in Finnish sheep

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    Hautaniemi Maria

    2012-07-01

    Full Text Available Abstract Background The progression of scrapie is known to be influenced by the amino acid polymorphisms of the host prion protein (PrP gene. There is no breeding programme for TSE resistance in sheep in Finland, but a scrapie control programme has been in place since 1995. In this study we have analysed PrP genotypes of total of 928 purebred and crossbred sheep together with the data of scrapie survey carried out in Finland during 2002–2008 in order to gain knowledge of the genotype distribution and scrapie prevalence in Finnish sheep. Results The ARQ/ARQ genotype was the most common genotype in all breeds studied. ARR allele frequency was less than 12% in purebred Finnish sheep and in most genotypes heterozygous for ARR, the second allele was ARQ. The VRQ allele was not detected in the Grey race sheep of Kainuu or in the Aland sheep, and it was present in less than 6% of the Finnish Landrace sheep. Leucine was the most prominent amino acid found in codon 141. In addition, one novel prion dimorphisms of Q220L was detected. During the scrapie survey of over 15 000 sheep in 2002–2008, no classical scrapie cases and only five atypical scrapie cases were detected. Conclusions The results indicate that the Finnish sheep populations have genetically little resistance to classical scrapie, but no classical scrapie was detected during an extensive survey in 2002–2008. However, five atypical scrapie cases emerged; thus, the disease is present in the Finnish sheep population at a low level.

  9. Archival search for historical atypical scrapie in sheep reveals evidence for mixed infections.

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    Chong, Angela; Kennedy, Iain; Goldmann, Wilfred; Green, Andrew; González, Lorenzo; Jeffrey, Martin; Hunter, Nora

    2015-10-01

    Natural scrapie in sheep occurs in classical and atypical forms, which may be distinguished on the basis of the associated neuropathology and properties of the disease-associated prion protein on Western blots. First detected in 1998, atypical scrapie is known to have occurred in UK sheep since the 1980s. However, its aetiology remains unclear and it is often considered as a sporadic, non-contagious disease unlike classical scrapie which is naturally transmissible. Although atypical scrapie tends to occur in sheep of prion protein (PRNP) genotypes that are different from those found predominantly in classical scrapie, there is some overlap so that there are genotypes in which both scrapie forms can occur. In this search for early atypical scrapie cases, we made use of an archive of fixed and frozen sheep samples, from both scrapie-affected and healthy animals (∼1850 individuals), dating back to the 1960s. Using a selection process based primarily on PRNP genotyping, but also on contemporaneous records of unusual clinical signs or pathology, candidate sheep samples were screened by Western blot, immunohistochemistry and strain-typing methods using tg338 mice. We identified, from early time points in the archive, three atypical scrapie cases, including one sheep which died in 1972 and two which showed evidence of mixed infection with classical scrapie. Cases with both forms of scrapie in the same animal as recognizable entities suggest that mixed infections have been around for a long time and may potentially contribute to the variety of scrapie strains.

  10. Atypical scrapie prions from sheep and lack of disease in transgenic mice overexpressing human prion protein.

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    Wadsworth, Jonathan D F; Joiner, Susan; Linehan, Jacqueline M; Balkema-Buschmann, Anne; Spiropoulos, John; Simmons, Marion M; Griffiths, Peter C; Groschup, Martin H; Hope, James; Brandner, Sebastian; Asante, Emmanuel A; Collinge, John

    2013-11-01

    Public and animal health controls to limit human exposure to animal prions are focused on bovine spongiform encephalopathy (BSE), but other prion strains in ruminants may also have zoonotic potential. One example is atypical/Nor98 scrapie, which evaded statutory diagnostic methods worldwide until the early 2000s. To investigate whether sheep infected with scrapie prions could be another source of infection, we inoculated transgenic mice that overexpressed human prion protein with brain tissue from sheep with natural field cases of classical and atypical scrapie, sheep with experimental BSE, and cattle with BSE. We found that these mice were susceptible to BSE prions, but disease did not develop after prolonged postinoculation periods when mice were inoculated with classical or atypical scrapie prions. These data are consistent with the conclusion that prion disease is less likely to develop in humans after exposure to naturally occurring prions of sheep than after exposure to epizootic BSE prions of ruminants.

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

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    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.

  12. Classical scrapie prions in ovine blood are associated with B lymphocytes and platelet-rich plasma

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    Dassanayake Rohana P

    2011-11-01

    Full Text Available Abstract Background Classical scrapie is a naturally occurring transmissible spongiform encephalopathy of sheep and goats characterized by cellular accumulation of abnormal isoforms of prion protein (PrPSc in the central nervous system and the follicles of peripheral lymphoid tissues. Previous studies have shown that the whole blood and buffy coat blood fraction of scrapie infected sheep harbor prion infectivity. Although PrPSc has been detected in peripheral blood mononuclear cells (PBMCs, plasma, and more recently within a subpopulation of B lymphocytes, the infectivity status of these cells and plasma in sheep remains unknown. Therefore, the objective of this study was to determine whether circulating PBMCs, B lymphocytes and platelets from classical scrapie infected sheep harbor prion infectivity using a sheep bioassay. Results Serial rectal mucosal biopsy and immunohistochemistry were used to detect preclinical infection in lambs transfused with whole blood or blood cell fractions from preclinical or clinical scrapie infected sheep. PrPSc immunolabeling was detected in antemortem rectal and postmortem lymphoid tissues from recipient lambs receiving PBMCs (15/15, CD72+ B lymphocytes (3/3, CD21+ B lymphocytes (3/3 or platelet-rich plasma (2/3 fractions. As expected, whole blood (11/13 and buffy coat (5/5 recipients showed positive PrPSc labeling in lymphoid follicles. However, at 549 days post-transfusion, PrPSc was not detected in rectal or other lymphoid tissues in three sheep receiving platelet-poor plasma fraction. Conclusions Prion infectivity was detected in circulating PBMCs, CD72+ pan B lymphocytes, the CD21+ subpopulation of B lymphocytes and platelet-rich plasma of classical scrapie infected sheep using a sheep bioassay. Combining platelets with B lymphocytes might enhance PrPSc detection levels in blood samples.

  13. A transfectant RK13 cell line permissive to classical caprine scrapie prion propagation

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    Classical scrapie is a form of transmissible spongiform encephalopathies (TSE) affecting domestic goats and sheep and disease is characterized by the accumulation of abnormal conformational isoform (PrP-Sc) of normal cellular prion protein (PrP-C) in the central nervous system and, in most cases, ly...

  14. Scrapie-Specific Pathology of Sheep Lymphoid Tissues

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    Gillian McGovern; Martin Jeffrey

    2007-01-01

    Transmissible spongiform encephalopathies (TSEs) or prion diseases often result in accumulation of disease-associated PrP (PrP(d)) in the lymphoreticular system (LRS), specifically in association with follicular dendritic cells (FDCs) and tingible body macrophages (TBMs) of secondary follicles. We studied the effects of sheep scrapie on lymphoid tissue in tonsils and lymph nodes by light and electron microscopy. FDCs of sheep were grouped according to morphology as immature, mature or regress...

  15. Scrapie-specific pathology of sheep lymphoid tissues.

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    Gillian McGovern

    Full Text Available Transmissible spongiform encephalopathies (TSEs or prion diseases often result in accumulation of disease-associated PrP (PrP(d in the lymphoreticular system (LRS, specifically in association with follicular dendritic cells (FDCs and tingible body macrophages (TBMs of secondary follicles. We studied the effects of sheep scrapie on lymphoid tissue in tonsils and lymph nodes by light and electron microscopy. FDCs of sheep were grouped according to morphology as immature, mature or regressing. Scrapie was associated with FDC dendrite hypertrophy and electron dense deposit or vesicles. PrP(d was located using immunogold labelling at the plasmalemma of FDC dendrites and, infrequently, mature B cells. Abnormal electron dense deposits surrounding FDC dendrites were identified as immunoglobulins suggesting that excess immune complexes are retained and are indicative of an FDC dysfunction. Within scrapie-affected lymph nodes, macrophages outside the follicle and a proportion of germinal centre TBMs accumulated PrP(d within endosomes and lysosomes. In addition, TBMs showed PrP(d in association with the cell membrane, non-coated pits and vesicles, and also with discrete, large and random endoplasmic reticulum networks, which co-localised with ubiquitin. These observations suggest that PrP(d is internalised via the caveolin-mediated pathway, and causes an abnormal disease-related alteration in endoplasmic reticulum structure. In contrast to current dogma, this study shows that sheep scrapie is associated with cytopathology of germinal centres, which we attribute to abnormal antigen complex trapping by FDCs and abnormal endocytic events in TBMs. The nature of the sub-cellular changes in FDCs and TBMs differs from those of scrapie infected neurones and glial cells suggesting that different PrP(d/cell membrane interactions occur in different cell types.

  16. Scrapie-specific pathology of sheep lymphoid tissues.

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    McGovern, Gillian; Jeffrey, Martin

    2007-01-01

    Transmissible spongiform encephalopathies (TSEs) or prion diseases often result in accumulation of disease-associated PrP (PrP(d)) in the lymphoreticular system (LRS), specifically in association with follicular dendritic cells (FDCs) and tingible body macrophages (TBMs) of secondary follicles. We studied the effects of sheep scrapie on lymphoid tissue in tonsils and lymph nodes by light and electron microscopy. FDCs of sheep were grouped according to morphology as immature, mature or regressing. Scrapie was associated with FDC dendrite hypertrophy and electron dense deposit or vesicles. PrP(d) was located using immunogold labelling at the plasmalemma of FDC dendrites and, infrequently, mature B cells. Abnormal electron dense deposits surrounding FDC dendrites were identified as immunoglobulins suggesting that excess immune complexes are retained and are indicative of an FDC dysfunction. Within scrapie-affected lymph nodes, macrophages outside the follicle and a proportion of germinal centre TBMs accumulated PrP(d) within endosomes and lysosomes. In addition, TBMs showed PrP(d) in association with the cell membrane, non-coated pits and vesicles, and also with discrete, large and random endoplasmic reticulum networks, which co-localised with ubiquitin. These observations suggest that PrP(d) is internalised via the caveolin-mediated pathway, and causes an abnormal disease-related alteration in endoplasmic reticulum structure. In contrast to current dogma, this study shows that sheep scrapie is associated with cytopathology of germinal centres, which we attribute to abnormal antigen complex trapping by FDCs and abnormal endocytic events in TBMs. The nature of the sub-cellular changes in FDCs and TBMs differs from those of scrapie infected neurones and glial cells suggesting that different PrP(d)/cell membrane interactions occur in different cell types. PMID:18074028

  17. An economic evaluation of preclinical testing strategies compared to the compulsory scrapie flock scheme in the control of classical scrapie.

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    Lisa Boden; Ian Handel; Neil Hawkins; Fiona Houston; Helen Fryer; Rowland Kao

    2012-01-01

    Cost-benefit is rarely combined with nonlinear dynamic models when evaluating control options for infectious diseases. The current strategy for scrapie in Great Britain requires that all genetically susceptible livestock in affected flocks be culled (Compulsory Scrapie Flock Scheme or CSFS). However, this results in the removal of many healthy sheep, and a recently developed pre-clinical test for scrapie now offers a strategy based on disease detection. We explore the flock level cost-effecti...

  18. Scrapie e seu diagnóstico diferencial em ovinos no Mato Grosso do Sul Scrapie and differential diagnosis in sheep in Mato Grosso do Sul, Brazil

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    Héllen M. Martins

    2012-12-01

    Full Text Available Scrapie é uma doença infecciosa, neurodegenerativa fatal, causada pelo príon scrapie (PrPsc. Apresenta-se tanto na forma clássica em ovinos e caprinos geneticamente susceptíveis quanto na forma atípica em ovinos. A primeira notificação oficial do Brasil à Organização Mundial de Saúde Animal (OIE, um caso da forma clássica diagnosticado no Rio Grande do Sul ocorreu em 1985, mas a doença já havia sido diagnosticada no mesmo Estado em 1978. Este trabalho objetivou descrever dois surtos de Scrapie em ovinos em Mato Grosso do Sul (MS, Brasil e investigar, por meio de imuno-histoquímica (IHQ a presença de PrPsc no Sistema Nervoso Central (SNC de ovinos examinados entre 2003 e 2010. Na primeira parte observaram-se dois ovinos com sinais clínicos típicos de scrapie, detalhando-se os sinais neurológicos, dados epidemiológicos, histopatológicos e amostras teciduais em duplicata desses ovinos foram encaminhadas para realização de diagnóstico de Raiva e para diagnóstico IHQ para príon. Na segunda parte realizou-se levantamento de laudos de necropsia e diagnósticos histopatológicos de ovinos, no período de maio de 2003 a março de 2010. Amostras de sistema nervoso central de 51 casos foram selecionados, incluindo os dois já com diagnóstico de Scrapie mencionados acima; os tecido de todos esses ovinos foram submetidos à IHQ para detecção de proteína priônica. Os 49 ovinos avaliados apresentaram resultado negativo na IHQ para príon.Scrapie is a fatal neurodegenerative infectious disease, caused by the scrapie prion (PrPsc, that can both in the as the classic form in genetically susceptible sheep and goats and in the atypical form in sheep. The first official notification of scrapie from Brazil was made to the World Organization for Animal Health (OIE in 1985, in the state of Rio Grande do Sul, although the disease was first documented in this Brazilian state in 1978. The objective this paper was to describe two outbreaks

  19. Review: A review on classical and atypical scrapie in caprine: Prion protein gene polymorphisms and their role in the disease.

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    Curcio, L; Sebastiani, C; Di Lorenzo, P; Lasagna, E; Biagetti, M

    2016-10-01

    Scrapie is a naturally occurring transmissible spongiform encephalopathy in sheep and goat. It has been known for ~250 years and is characterised by the accumulation of an abnormal isoform of a host-encoded prion protein that leads to progressive neurodegeneration and death. Scrapie is recognised in two forms, classical and atypical scrapie. The susceptibility to both types of scrapie is influenced by polymorphisms of the prion protein gene (PRNP). Sheep susceptibility or resistance to classical scrapie is strongly regulated by the polymorphisms at codons 136, 154 and 171 of the PRNP. The genetic role in atypical scrapie in sheep has been defined by polymorphisms at codons 141, 154 and 171, which are associated with different degrees of risk in the occurrence of the ovine disease. Progress has been achieved in the prevention of scrapie in sheep due to efficient genetic breeding programmes based on eradication and control of the disease. In Europe, the success of these programmes has been verified by applying eradication and genetic selection plans. In general terms, the ovine selection plans aim to eliminate and reduce the susceptible allele and to enrich the resistant allele ARR. During outbreaks all susceptible animals are slaughtered, only ARR/ARR resistant rams and sheep and semi-resistant females are preserved. In the occurrence of scrapie positive goats a complete cull of the flock (stamping out) is performed with great economic loss and severe risk of extinction for the endangered breeds. The ability to select scrapie-resistant animals allows to define new breeding strategies aimed to boost genetic progress while reducing costs during scrapie outbreaks. Allelic variants of PRNP can be protective for caprine scrapie, and the knowledge of their distribution in goats has become very important. Over the past few years, the integration of genetic information on goat populations could be used to make selection decisions, commonly referred to as genetic selection

  20. Norwegian farmers' vigilance in reporting sheep showing scrapie-associated signs

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    Jarp Jorun

    2007-12-01

    Full Text Available Abstract Background Scrapie is a chronic neurodegenerative disease affecting small ruminants and belongs to the transmissible spongiform encephalopathies. Scrapie is considered a serious animal disease and it has been notifiable in Norway since 1965. The clinical signs of scrapie might be vague and the farmers, if familiar with the signs of scrapie, are often in the best position for detecting scrapie suspects. In 2002, an anonymous questionnaire survey was conducted in order to assess Norwegian sheep farmers' vigilance of scrapie. Results Although the potential detection of a scrapie-positive animal would lead to the destruction of the sheep flock concerned, almost all the farmers (97 % expressed their willingness to report scrapie suspects. This was most certainly dependent on the Government taking the economic responsibility for the control programme as nearly all the farmers responded that this was an important condition. Listeriosis is relatively common disease in Norwegian sheep and a differential diagnosis for scrapie. In a multinomial logistic regression the reporting behaviour for non-recovering listeriosis cases, used as a measurement of willingness to report scrapie, was examined. The reporting of non-recovering listeriosis cases increased as the knowledge of scrapie-associated signs increased, and the reporting behaviour was dependent on both economic and non-economic values. Conclusion The results indicate that in 2002 almost all sheep farmers showed willingness to report any scrapie suspects. Nevertheless there is an underreporting of scrapie suspects and the farmers' awareness and hence their vigilance of scrapie could be improved. Furthermore, the results suggest that to ensure the farmers' compliance to control programmes for serious infectious diseases, the farmers' concerns of non-economic as well as economic values should be considered.

  1. Comparison of strategies for substantiating freedom from scrapie in a sheep flock

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    Ducrot Christian

    2009-04-01

    Full Text Available Abstract Background The public health threat represented by a potential circulation of bovine spongiform encephalopathy agent in sheep population has led European animal health authorities to launch large screening and genetic selection programmes. If demonstrated, such a circulation would have dramatic economic consequences for sheep breeding sector. In this context, it is important to evaluate the feasibility of qualification procedures that would allow sheep breeders demonstrating their flock is free from scrapie. Classical approaches, based on surveys designed to detect disease presence, do not account for scrapie specificities: the genetic variations of susceptibility and the absence of live diagnostic test routinely available. Adapting these approaches leads to a paradoxical situation in which a greater amount of testing is needed to substantiate disease freedom in genetically resistant flocks than in susceptible flocks, whereas probability of disease freedom is a priori higher in the former than in the latter. The goal of this study was to propose, evaluate and compare several qualification strategies for demonstrating a flock is free from scrapie. Results A probabilistic framework was defined that accounts for scrapie specificities and allows solving the preceding paradox. Six qualification strategies were defined that combine genotyping data, diagnostic tests results and flock pedigree. These were compared in two types of simulated flocks: resistant and susceptible flocks. Two strategies allowed demonstrating disease freedom in several years, for the majority of simulated flocks: a strategy in which all the flock animals are genotyped, and a strategy in which only founders animals are genotyped, the flock pedigree being known. In both cases, diagnostic tests are performed on culled animals. The less costly strategy varied according to the genetic context (resistant or susceptible and to the relative costs of a genotyping exam and of a

  2. A case-control study on scrapie in Norwegian sheep flocks.

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    Hopp, P; Ulvund, M J; Jarp, J

    2001-10-11

    Scrapie first was detected in indigenous sheep in Norway in 1981, and from 1995 to 1997 an increase in the number of flocks with scrapie cases was recorded. These flocks were mainly in one geographical region. A study to identify risk factors for scrapie was conducted. The study had three frequency-matched controls selected for every case within the same Veterinary District. A questionnaire was submitted to 176 sheep flocks (42 had been scrapie flocks). The data obtained by the questionnaire were linked to data collected from governmental and industry registers. After imputing missing data using single random imputation, the statistical analysis was performed using multivariable conditional logistic regression. Purchase of female sheep from scrapie flocks, sharing of rams, or sharing of pastures between different flocks were the risk factors associated with the occurrence of scrapie. Of factors potentially sustaining and promoting the infection in the flock, number of winter-fed sheep, number of buildings for housing sheep, rams and ewes shared room during mating period and increase in the flock size were associated with scrapie. We interpret these findings to show that factors involving transfer of sheep between flocks or direct contact between sheep of different flocks are important for the spread of scrapie. Management factors are important for the development of scrapie. However, it was not possible to discriminate between the different management factors in this study at the flock level. Also, factors indicating awareness and interest of the farmer (as well as willingness to contact a veterinarian for diseased sheep) were related to the detection of scrapie in the flock.

  3. Scrapie prevalence in sheep of susceptible genotype is declining in a population subject to breeding for resistance

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    Engel Bas; Davidse Aart; Bossers Alex; Melchior Marielle B; Hagenaars Thomas J; van Zijderveld Fred G

    2010-01-01

    Abstract Background Susceptibility of sheep to scrapie infection is known to be modulated by the PrP genotype of the animal. In the Netherlands an ambitious scrapie control programme was started in 1998, based on genetic selection of animals for breeding. From 2002 onwards EU regulations required intensive active scrapie surveillance as well as certain control measures in affected flocks. Here we analyze the data on genotype frequencies and scrapie prevalence in the Dutch sheep population obt...

  4. Cholesterol Metabolism in Brain and Skin Fibroblasts from Sarda Breed Sheep With Scrapie-resistant and Scrapie-susceptible Genotypes

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    Alessandra Pani

    2007-01-01

    Full Text Available Scrapie is a fatal spongiform encephalopathy of sheep, a transmissible form of prion disease caused by neuronal accumulation of the aberrantly conformed prion protein (PrPsc. Currently, no ante-mortem diagnostic tests are available to detect this untreatable disease in the pre-clinical stage, thus making difficult to control its spread. Recent evidence suggests that the production of PrPsc can be modulated by the levels of membrane cholesterol in neuronal cells. Since cholesterol levels in cell membranes are dependent on cholesterol homeostasis in the whole organism, we studied cholesterol metabolism in brain tissues, plasma and skin fibroblasts of Sarda breed sheep with scrapie-resistant (ARR/ARR and scrapie-susceptible (ARQ/ARQ prion protein genotypes, both not infected (ARQ/ARQ- and infected (ARQ/ARQ+ with scrapie. We found that, the levels of cytoplasmic cholesterol esters (CE in brains and skin fibroblasts from sheep with the ARQ/ARQ genotype were consistently higher than those from sheep with the ARR/ARR genotype. Conversely, the levels of free cholesterol (FC were lower in ARQ/ARQ, as compared to ARR/ARR sheep, thus resulting in a sharp reduction of the FC/CE ratio. Moreover, both uninfected and infected ARQ/ARQ sheep showed abnormally low levels of high density lipoprotein-cholesterol (HDL-C in their plasma, as compared to ARR/ARR sheep. These data other than adding new strength to the notion that altered levels of intracellular cholesterol may indicate the presence of a lipid metabolic state that predisposes to infection with, and accumulation of, PrPsc in the brain, discriminate for the first time between two distinct but related cellular pools of cholesterol, namely membrane FC on one hand and cytoplasmic CE on the other.

  5. Accumulation of Cholesterol Esters in ex vivo Lymphocytes from Scrapie-susceptible Sheep and in Scrapie-infected Mouse Neuroblastoma Cell Lines

    Directory of Open Access Journals (Sweden)

    Alessandra Pani

    2007-01-01

    Full Text Available Our studies on the role of cholesterol homeostasis in the pathogenesis of scrapie in sheep, revealed abnormal accumulation of cholesterol esters in brains and in ex vivo skin fibroblasts from genetically scrapie-susceptible, as compared to sheep with resistant genotype. We now report that PBMCs isolated from scrapie-susceptible sheep, as well as mouse neuroblastoma cell lines persistently infected with two different mouse-adapted strains of scrapie, showed similar alterations with up to 3-fold higher cholesterol ester levels than their resistant or uninfected counterparts. Treatments with drugs that interfere with intracellular cholesterol metabolism strongly reduced accumulation of cholesterol esters in scrapie-infected cell lines, whereas had significantly lower, or no effect, in uninfected cell line. These data add support to our hypothesis that accumulation of cholesterol esters may represent a biological marker of susceptibility to prion infection and a potential molecular target for prion inhibitors.

  6. Rapid and discriminatory diagnosis of scrapie and BSE in retro-pharyngeal lymph nodes of sheep

    Directory of Open Access Journals (Sweden)

    van Zijderveld Fred G

    2006-06-01

    Full Text Available Abstract Background Diagnosis based on prion detection in lymph nodes of sheep and goats can improve active surveillance for scrapie and, if it were circulating, for bovine spongiform encephalopathy (BSE. With sizes that allow repetitive testing and a location that is easily accessible at slaughter, retropharyngeal lymph nodes (RLN are considered suitable organs for testing. Western blotting (WB of brain homogenates is, in principle, a technique well suited to both detect and discriminate between scrapie and BSE. In this report, WB is developed for rapid diagnosis in RLN and to study biochemical characteristics of PrPres. Results Optimal PrPres detection in RLN by WB was achieved by proper tissue processing, antibody choice and inclusion of a step for PrPresconcentration. The analyses were performed on three different sheep sources. Firstly, in a study with preclinical scrapie cases, WB of RLN from infected sheep of VRQ/VRQ genotype – VRQ represents, respectively, polymorphic PrP amino acids 136, 154, and 171 – allowed a diagnosis 14 mo earlier compared to WB of brain stem. Secondly, samples collected from sheep with confirmed scrapie in the course of passive and active surveillance programmes in the period 2002–2003 yielded positive results depending on genotype: all sheep with genotypes ARH/VRQ, VRQ/VRQ, and ARQ/VRQ scored positive for PrPres, but ARQ/ARQ and ARR/VRQ were not all positive. Thirdly, in an experimental BSE study, detection of PrPres in all 11 ARQ/ARQ sheep, including 7 preclinical cases, was possible. In all instances, WB and IHC were almost as sensitive. Moreover, BSE infection could be discriminated from scrapie infection by faster electrophoretic migration of the PrPres bands. Using dual antibody staining with selected monoclonal antibodies like 12B2 and L42, these differences in migration could be employed for an unequivocal differentiation between BSE and scrapie. With respect to glycosylation of PrPres, BSE cases

  7. Atypical Scrapie Prions from Sheep and Lack of Disease in Transgenic Mice Overexpressing Human Prion Protein

    OpenAIRE

    Wadsworth, Jonathan D. F.; Joiner, Susan; Linehan, Jacqueline M; Balkema-Buschmann, Anne; Spiropoulos, John; Simmons, Marion M; Griffiths, Peter C; Martin H Groschup; Hope, James; Brandner, Sebastian; Asante, Emmanuel A.; Collinge, John

    2013-01-01

    Public and animal health controls to limit human exposure to animal prions are focused on bovine spongiform encephalopathy (BSE), but other prion strains in ruminants may also have zoonotic potential. One example is atypical/Nor98 scrapie, which evaded statutory diagnostic methods worldwide until the early 2000s. To investigate whether sheep infected with scrapie prions could be another source of infection, we inoculated transgenic mice that overexpressed human prion protein with brain tissue...

  8. Scrapie prevalence in sheep of susceptible genotype is declining in a population subject to breeding for resistance

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    Engel Bas

    2010-05-01

    Full Text Available Abstract Background Susceptibility of sheep to scrapie infection is known to be modulated by the PrP genotype of the animal. In the Netherlands an ambitious scrapie control programme was started in 1998, based on genetic selection of animals for breeding. From 2002 onwards EU regulations required intensive active scrapie surveillance as well as certain control measures in affected flocks. Here we analyze the data on genotype frequencies and scrapie prevalence in the Dutch sheep population obtained from both surveillance and affected flocks, to identify temporal trends. We also estimate the genotype-specific relative risks to become a detected scrapie case. Results We find that the breeding programme has produced a steady increase in the level of genetic scrapie resistance in the Dutch sheep population. We also find that a significant decline in the prevalence of scrapie in tested animals has occurred a number of years after the start of the breeding programme. Most importantly, the estimated scrapie prevalence level per head of susceptible genotype is also declining significantly, indicating that selective breeding causes a population effect. Conclusions The Dutch scrapie control programme has produced a steady rise in genetic resistance levels in recent years. A recent decline in the scrapie prevalence per tested sheep of susceptible prion protein genotype indicates that selective breeding causes the desired population effect.

  9. Intraepithelial and interstitial deposition of pathological prion protein in kidneys of scrapie-affected sheep.

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    Ciriaco Ligios

    Full Text Available Prions have been documented in extra-neuronal and extra-lymphatic tissues of humans and various ruminants affected by Transmissible Spongiform Encephalopathy (TSE. The presence of prion infectivity detected in cervid and ovine blood tempted us to reason that kidney, the organ filtrating blood derived proteins, may accumulate disease associated PrP(Sc. We collected and screened kidneys of experimentally, naturally scrapie-affected and control sheep for renal deposition of PrP(Sc from distinct, geographically separated flocks. By performing Western blot, PET blot analysis and immunohistochemistry we found intraepithelial (cortex, medulla and papilla and occasional interstitial (papilla deposition of PrP(Sc in kidneys of scrapie-affected sheep. Interestingly, glomerula lacked detectable signals indicative of PrP(Sc. PrP(Sc was also detected in kidneys of subclinical sheep, but to significantly lower degree. Depending on the stage of the disease the incidence of PrP(Sc in kidney varied from approximately 27% (subclinical to 73.6% (clinical in naturally scrapie-affected sheep. Kidneys from flocks without scrapie outbreak were devoid of PrP(Sc. Here we demonstrate unexpectedly frequent deposition of high levels of PrP(Sc in ovine kidneys of various flocks. Renal deposition of PrP(Sc is likely to be a pre-requisite enabling prionuria, a possible co-factor of horizontal prion-transmission in sheep.

  10. A transfectant RK13 cell line permissive to classical caprine scrapie prion propagation.

    Science.gov (United States)

    Dassanayake, Rohana P; Zhuang, Dongyue; Truscott, Thomas C; Madsen-Bouterse, Sally A; O'Rourke, Katherine I; Schneider, David A

    2016-03-01

    To assess scrapie infectivity associated with caprine-origin tissues, bioassay can be performed using kids, lambs or transgenic mice expressing caprine or ovine prion (PRNP) alleles, but the incubation periods are fairly long. Although several classical ovine scrapie prion permissive cell lines with the ability to detect brain-derived scrapie prion have been available, no classical caprine scrapie permissive cell line is currently available. Therefore, the aims of this study were to generate a rabbit kidney epithelial cell line (RK13) stably expressing caprine wild-type PRNP (cpRK13) and then to assess permissiveness of cpRK13 cells to classical caprine scrapie prion propagation. The cpRK13 and plasmid control RK13 (pcRK13) cells were incubated with brain-derived classical caprine scrapie inocula prepared from goats or ovinized transgenic mice (Tg338, express ovine VRQ allele) infected with caprine scrapie. Significant PrP(Sc) accumulation, which is indicative of scrapie prion propagation, was detected by TSE ELISA and immunohistochemistry in cpRK13 cells inoculated with classical caprine scrapie inocula. Western blot analysis revealed the typical proteinase K-resistant 3 PrP(res) isoforms in the caprine scrapie prion inoculated cpRK13 cell lysate. Importantly, PrP(Sc) accumulation was not detected in similarly inoculated pcRK13 cells, whether by TSE ELISA, immunohistochemistry, or western blot. These findings suggest that caprine scrapie prions can be propagated in cpRK13 cells, thus this cell line may be a useful tool for the assessment of classical caprine prions in the brain tissues of goats. PMID:27216989

  11. Dynamics of a scrapie outbreak in a flock of Romanov sheep-estimation of transmission parameters

    NARCIS (Netherlands)

    Hagenaars, T.H.J.; Donelly, C.A.; Ferguson, N.M.; Anderson, R.M.

    2003-01-01

    Knowledge of epidemiological mechanisms and parameters underlying scrapie transmission in sheep flocks remains very limited at present. Here we introduce a method for fitting stochastic transmission models to outbreak data to estimate bounds on key transmission parameters. We apply this method to da

  12. An economic evaluation of preclinical testing strategies compared to the compulsory scrapie flock scheme in the control of classical scrapie.

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    Lisa Boden

    Full Text Available Cost-benefit is rarely combined with nonlinear dynamic models when evaluating control options for infectious diseases. The current strategy for scrapie in Great Britain requires that all genetically susceptible livestock in affected flocks be culled (Compulsory Scrapie Flock Scheme or CSFS. However, this results in the removal of many healthy sheep, and a recently developed pre-clinical test for scrapie now offers a strategy based on disease detection. We explore the flock level cost-effectiveness of scrapie control using a deterministic transmission model and industry estimates of costs associated with genotype testing, pre-clinical tests and the value of a sheep culled. Benefit was measured in terms of the reduction in the number of infected sheep sold on, compared to a baseline strategy of doing nothing, using Incremental Cost Effectiveness analysis to compare across strategies. As market data was not available for pre-clinical testing, a threshold analysis was used to set a unit-cost giving equal costs for CSFS and multiple pre-clinical testing (MT, one test each year for three consecutive years. Assuming a 40% within-flock proportion of susceptible genotypes and a test sensitivity of 90%, a single test (ST was cheaper but less effective than either the CSFS or MT strategies (30 infected-sales-averted over the lifetime of the average epidemic. The MT strategy was slightly less effective than the CSFS and would be a dominated strategy unless preclinical testing was cheaper than the threshold price of £6.28, but may be appropriate for flocks with particularly valuable livestock. Though the ST is not currently recommended, the proportion of susceptible genotypes in the national flock is likely to continue to decrease; this may eventually make it a cost-effective alternative to the MT or CSFS.

  13. EFSA Panel on Biological Hazards (BIOHAZ); Scientific Opinion on the risk of transmission of classical scrapie via in vivo derived embryo transfer in ovine animals

    DEFF Research Database (Denmark)

    Hald, Tine; Baggesen, Dorte Lau

    . Under natural exposure conditions, animals that are heterozygous or homozygous A136R154R171 display respectively a low or negligible risk of being infected. The genetic control of the susceptibility to classical scrapie is also likely to impact on the risk of transmitting the disease via embryo transfer......The risk of transmission of classical scrapie via the transfer of in vivo derived embryo in ovines was assessed, taking into account the scientific information made available since the last EFSA opinion on this topic (2010) (see http://www.efsa.europa.eu/en/efsajournal/pub/1429.htm). The potential...... impact of PrP genotype of the embryo and/or of the ram and donor ewe on this risk was also assessed. The new data made available over the last three years further reinforce the view that classical scrapie could be vertically transmitted in sheep. Since the possibility of such vertical transmission...

  14. Biology of PrPsc accumulation in two natural scrapie-infected sheep flocks.

    Science.gov (United States)

    Caplazi, Patrick; O'Rourke, Katherine; Wolf, Cynthia; Shaw, Daniel; Baszler, Timothy V

    2004-11-01

    Sheep scrapie is a prion disease that requires interaction of exogenous prions with host prion protein (PrP) supporting prion formation. Disease is associated with deposition of a host-generated conformational variant of PrP, PrPsc, in a variety of tissues, including brain, resulting in fatal spongiform encephalopathy. Efficiency of PrPsc formation is determined by polymorphisms in the PrP-coding sequence. This article adds to previous data of natural sheep scrapie, concentrating on the effect of host genotype and age on PrPsc accumulation patterns during preclinical and clinical disease. Two entire scrapie-infected, predominantly Suffolk-cross, sheep flocks euthanized for regulatory purposes were genotyped and analyzed for PrPsc deposition in various tissues using single- and dual-label immunohistochemistry. Scrapie, as defined by PrPsc deposition, occurred in 13/80 sheep. Preclinical disease was evident in nearly 70% of infected sheep, ranging in age from 14 months to 7 years. PrPsc accumulated systemically in the nervous tissue, various lymphoid tissues, both alimentary tract related and non-alimentary tract related, and the placenta. Clinical neurological illness was always associated with spongiform encephalopathy and PrPsc deposition in the brain. Only 6 of 9 sheep with preclinical scrapie had PrPsc deposition in the brain but widespread PrPsc deposition in peripheral lymphoid tissue, supporting previous data showing peripheral PrPsc accumulation preceding deposition in the brain. PrPsc colocalized with a marker for follicular dendritic cells throughout the lymphoid system. PrPsc also accumulated in the peripheral nervous system, particularly the nervous supply of the gastrointestinal tract. Abundant PrPsc was evident in trophoblast cells of placentomes but not in the endometrium, myometrium, or associated nervous plexus. PrPsc deposits were not observed in the mammary parenchyma or bone marrow. Scrapie susceptibility was defined genetically by PrP codon 171

  15. Evaluation of two commercial, rapid, ELISA kits testing or scrapie in retro-pharyngeal lymph nodes in sheep

    NARCIS (Netherlands)

    Kittelberger, R.; McIntuyre, L.; Watts, S.; MacDiarmid, S.; Hannah, M.J.; Jenner, J.; Bueno, R.; Swainsbury, R.; Langeveld, J.P.M.; Keulen, van L.J.M.; Zijderveld, van F.G.; Wemheuer, W.M.; Richt, J.A.; Sorenson, S.J.; Pigott, C.J.; O'Keefe, J.S.

    2014-01-01

    AIMS: To estimate the number of cases of scrapie that would occur in sheep of different prion protein (PrP) genotypes if scrapie was to become established in New Zealand, and to compare the performance of two commercially available, rapid ELISA kits using ovine retro-pharyngeal lymph nodes (RLN) fro

  16. Sensitive and specific detection of classical scrapie prions in the brains of goats by real-time quaking-induced conversion.

    Science.gov (United States)

    Dassanayake, Rohana P; Orrú, Christina D; Hughson, Andrew G; Caughey, Byron; Graça, Telmo; Zhuang, Dongyue; Madsen-Bouterse, Sally A; Knowles, Donald P; Schneider, David A

    2016-03-01

    Real-time quaking-induced conversion (RT-QuIC) is a rapid, specific and highly sensitive prion seeding activity detection assay that uses recombinant prion protein (rPrPSen) to detect subinfectious levels of the abnormal isoforms of the prion protein (PrPSc). Although RT-QuIC has been successfully used to detect PrPSc in various tissues from humans and animals, including sheep, tissues from goats infected with classical scrapie have not yet been tested. Therefore, the aims of the present study were to (1) evaluate whether prion seeding activity could be detected in the brain tissues of goats with scrapie using RT-QuIC, (2) optimize reaction conditions to improve scrapie detection in goats, and (3) compare the performance of RT-QuIC for the detection of PrPSc with the more commonly used ELISA and Western blot assays. We further optimized RT-QuIC conditions for sensitive and specific detection of goat scrapie seeding activity in brain tissue from clinical animals. When used with 200  mM sodium chloride, both full-length sheep rPrPSen substrates (PrP genotypes A136R154Q171 and V136R154Q171) provided good discrimination between scrapie-infected and normal goat brain samples at 10(- )3 dilution within 15  h. Our findings indicate that RT-QuIC was at least 10,000-fold more sensitive than ELISA and Western blot assays for the detection of scrapie seeding activity in goat brain samples. In addition to PRNP WT samples, positive RT-QuIC reactions were also observed with three PRNP polymorphic goat brain samples (G/S127, I/M142 and H/R143) tested. Taken together, these findings demonstrate that RT-QuIC sensitively detects prion seeding activity in classical scrapie-infected goat brain samples. PMID:26653410

  17. Detection and clinical evolution of scrapie in sheep by 3rd eyelid biopsy.

    Science.gov (United States)

    Vargas, Francisco; Luján, Lluís; Bolea, Rosa; Monleón, Eva; Martín-Burriel, Inmaculada; Fernández, Antonio; De Blas, Ignacio; Badiola, Juan José

    2006-01-01

    The goal of this article was to characterize the clinical evolution of scrapie in naturally affected sheep. Eighteen sheep with scrapie diagnosed by examination of 3rd eyelid biopsy and 12 control ewes were studied throughout the duration of their disease. Diagnosis was confirmed postmortem by histopathologic, immunohistochemical, and Western blot analysis of nervous tissue. Complete clinical examinations were performed every 2 weeks for each animal, of which 3 clinical examinations per animal are reported. Those clinical signs that showed a significant frequency within the corresponding clinical examination were considered representative of each stage of the disease (ie, early, middle, and late). The representative clinical signs for the early stage were hypoesthesia in the limbs, alteration of mental status, and a body condition score gait abnormalities, and teeth grinding. On the basis of these results, we propose the calculation of an objective clinical index that allows the differentiation among clinical stages and that could be useful for further studies. The usefulness of 3rd eyelid lymphoid tissue biopsies for sequential clinical studies in naturally scrapie-affected sheep is demonstrated. PMID:16496940

  18. Disease-associated PrP in the enteric nervous system of scrapie-affected Suffolk sheep.

    Science.gov (United States)

    Heggebø, Ragna; González, Lorenzo; Press, Charles McL; Gunnes, Gjermund; Espenes, Arild; Jeffrey, Martin

    2003-05-01

    Disease-associated prion protein (PrP(d)) in the enteric nervous system (ENS) of 20- to 24-month-old Suffolk sheep in the late subclinical and early clinical phase of scrapie was studied. Sites in the alimentary tract extending from the forestomachs and abomasum to the colon from scrapie-affected sheep (PrP(ARQ/ARQ)) and scrapie-resistant sheep (PrP(ARR/ARQ) and PrP(ARR/ARR)) were examined. PrP(d) was found only in scrapie-affected sheep and was most prominent in the ENS when abundant deposits of PrP(d) were also present in adjacent lymphoid nodules. Immunolabelling with the nerve fibre markers PgP 9.5 and neuron-specific enolase and the satellite cell marker glial fibrillary acidic protein revealed the extensive ganglionated networks of the myenteric and submucosal plexi. Fewer nerve fibres were present in the lamina propria, T-cell dominated interfollicular areas and dome regions of Peyer's patches. A substantial network of nerve fibres was detected in many lymphoid nodules of both the scrapie-affected and scrapie-resistant sheep. Nerve fibres were also detected within the capsule of lymphoid nodules. Electron microscopy revealed the presence of nerves in the lymphoid nodules, showing a close association with follicular dendritic cells, lymphocytes and tingible body macrophages. In demonstrating that lymphoid nodules in the Peyer's patches of scrapie-affected sheep possess a substantial network of nerve fibres, the present study shows that nodules provide close contact between nerve fibres and cell populations known to contain abundant PrP(d), including follicular dendritic cells and tingible body macrophages, and that gut-associated lymphoid nodules in sheep may represent an important site for neuroinvasion. PMID:12692300

  19. The Oral Secretion of Infectious Scrapie Prions Occurs in Preclinical Sheep with a Range of PRNP Genotypes

    OpenAIRE

    Gough, Kevin C; Baker, Claire A; Rees, Helen C.; Terry, Linda A; Spiropoulos, John; Thorne, Leigh; Maddison, Ben C

    2012-01-01

    Preclinical sheep with the highly scrapie-susceptible VRQ/VRQ PRNP genotype secrete prions from the oral cavity. In order to further understand the significance of orally available prions, buccal swabs were taken from sheep with a range of PRNP genotypes and analyzed by serial protein misfolding cyclic amplification (sPMCA). Prions were detected in buccal swabs from scrapie-exposed sheep of genotypes linked to high (VRQ/VRQ and ARQ/VRQ) and low (ARR/VRQ and AHQ/VRQ) lymphoreticular system inv...

  20. Distribution of peripheral PrP(Sc in sheep with naturally acquired scrapie.

    Directory of Open Access Journals (Sweden)

    María Carmen Garza

    Full Text Available Accumulation of prion protein (PrPSc in the central nervous system is the hallmark of transmissible spongiform encephalopathies. However, in some of these diseases such as scrapie or chronic wasting disease, the PrPSc can also accumulate in other tissues, particularly in the lymphoreticular system. In recent years, PrPSc in organs other than nervous and lymphoid have been described, suggesting that distribution of this protein in affected individuals may be much larger than previously thought. In the present study, 11 non-nervous/non-lymphoid organs from 16 naturally scrapie infected sheep in advanced stages of the disease were examined for the presence of PrPSc. Fourteen infected sheep were of the ARQ/ARQ PRNP genotype and 2 of the VRQ/VRQ, where the letters A, R, Q, and V represent the codes for amino-acids alanine, arginine, glutamine and valine, respectively. Adrenal gland, pancreas, heart, skin, urinary bladder and mammary gland were positive for PrPSc by immunohistochemistry and IDEXX HerdChek scrapie/BSE Antigen EIA Test in at least one animal. Lung, liver, kidney and skeletal muscle exhibited PrPSc deposits by immunohistochemistry only. To our knowledge, this is the first report regarding the presence of PrPSc in the heart, pancreas and urinary bladder in naturally acquired scrapie infections. In some other organs examined, in which PrPSc had been previously detected, PrPSc immunolabeling was observed to be associated with new structures within those organs. The results of the present study illustrate a wide dissemination of PrPSc in both ARQ/ARQ and VRQ/VRQ infected sheep, even when the involvement of the lymphoreticular system is scarce or absent, thus highlighting the role of the peripheral nervous system in the spread of PrPSc.

  1. Distribution of peripheral PrP(Sc) in sheep with naturally acquired scrapie.

    Science.gov (United States)

    Garza, María Carmen; Monzón, Marta; Marín, Belén; Badiola, Juan José; Monleón, Eva

    2014-01-01

    Accumulation of prion protein (PrPSc) in the central nervous system is the hallmark of transmissible spongiform encephalopathies. However, in some of these diseases such as scrapie or chronic wasting disease, the PrPSc can also accumulate in other tissues, particularly in the lymphoreticular system. In recent years, PrPSc in organs other than nervous and lymphoid have been described, suggesting that distribution of this protein in affected individuals may be much larger than previously thought. In the present study, 11 non-nervous/non-lymphoid organs from 16 naturally scrapie infected sheep in advanced stages of the disease were examined for the presence of PrPSc. Fourteen infected sheep were of the ARQ/ARQ PRNP genotype and 2 of the VRQ/VRQ, where the letters A, R, Q, and V represent the codes for amino-acids alanine, arginine, glutamine and valine, respectively. Adrenal gland, pancreas, heart, skin, urinary bladder and mammary gland were positive for PrPSc by immunohistochemistry and IDEXX HerdChek scrapie/BSE Antigen EIA Test in at least one animal. Lung, liver, kidney and skeletal muscle exhibited PrPSc deposits by immunohistochemistry only. To our knowledge, this is the first report regarding the presence of PrPSc in the heart, pancreas and urinary bladder in naturally acquired scrapie infections. In some other organs examined, in which PrPSc had been previously detected, PrPSc immunolabeling was observed to be associated with new structures within those organs. The results of the present study illustrate a wide dissemination of PrPSc in both ARQ/ARQ and VRQ/VRQ infected sheep, even when the involvement of the lymphoreticular system is scarce or absent, thus highlighting the role of the peripheral nervous system in the spread of PrPSc. PMID:24828439

  2. Detection of PrPres in genetically susceptible fetuses from sheep with natural scrapie.

    Directory of Open Access Journals (Sweden)

    María Carmen Garza

    Full Text Available Scrapie is a transmissible spongiform encephalopathy with a wide PrPres dissemination in many non-neural tissues and with high levels of transmissibility within susceptible populations. Mechanisms of transmission are incompletely understood. It is generally assumed that it is horizontally transmitted by direct contact between animals or indirectly through the environment, where scrapie can remain infectious for years. In contrast, in utero vertical transmission has never been demonstrated and has rarely been studied. Recently, the use of the protein misfolding cyclic amplification technique (PMCA has allowed prion detection in various tissues and excretions in which PrPres levels have been undetectable by traditional assays. The main goal of this study was to detect PrPres in fetal tissues and the amniotic fluid from natural scrapie infected ewes using the PMCA technique. Six fetuses from three infected pregnant ewes in an advanced clinical stage of the disease were included in the study. From each fetus, amniotic fluid, brain, spleen, ileo-cecal valve and retropharyngeal lymph node samples were collected and analyzed using Western blotting and PMCA. Although all samples were negative using Western blotting, PrPres was detected after in vitro amplification. Our results represent the first time the biochemical detection of prions in fetal tissues, suggesting that the in utero transmission of scrapie in natural infected sheep might be possible.

  3. Detection of PrPres in Genetically Susceptible Fetuses from Sheep with Natural Scrapie

    Science.gov (United States)

    Garza, María Carmen; Fernández-Borges, Natalia; Bolea, Rosa; Badiola, Juan José; Castilla, Joaquín; Monleón, Eva

    2011-01-01

    Scrapie is a transmissible spongiform encephalopathy with a wide PrPres dissemination in many non-neural tissues and with high levels of transmissibility within susceptible populations. Mechanisms of transmission are incompletely understood. It is generally assumed that it is horizontally transmitted by direct contact between animals or indirectly through the environment, where scrapie can remain infectious for years. In contrast, in utero vertical transmission has never been demonstrated and has rarely been studied. Recently, the use of the protein misfolding cyclic amplification technique (PMCA) has allowed prion detection in various tissues and excretions in which PrPres levels have been undetectable by traditional assays. The main goal of this study was to detect PrPres in fetal tissues and the amniotic fluid from natural scrapie infected ewes using the PMCA technique. Six fetuses from three infected pregnant ewes in an advanced clinical stage of the disease were included in the study. From each fetus, amniotic fluid, brain, spleen, ileo-cecal valve and retropharyngeal lymph node samples were collected and analyzed using Western blotting and PMCA. Although all samples were negative using Western blotting, PrPres was detected after in vitro amplification. Our results represent the first time the biochemical detection of prions in fetal tissues, suggesting that the in utero transmission of scrapie in natural infected sheep might be possible. PMID:22194786

  4. Active Surveillance for Scrapie by Third Eyelid Biopsy and Genetic Susceptibility Testing of Flocks of Sheep in Wyoming

    OpenAIRE

    O'Rourke, Katherine I.; Duncan, John V.; Logan, James R.; Anderson, Anne K.; Norden, Dianne K.; Williams, Elizabeth S.; Combs, Bret A.; Stobart, Robert H.; Moss, Gary E.; Sutton, Diane L

    2002-01-01

    Control of scrapie, an ovine transmissible spongiform encephalopathy or prion disorder, has been hampered by the lack of conventional antemortem diagnostic tests. Currently, scrapie is diagnosed by postmortem examination of the brain and lymphoid tissues for PrPSc, the protein marker for this group of disorders. For live, asymptomatic sheep, diagnosis using tonsil or third-eyelid lymphoid tissue biopsy and PrPSc assay has been described. To evaluate the feasibility and efficacy of third-eyeli...

  5. Architecture of secondary lymphoid tissue in sheep experimentally challenged with scrapie.

    Science.gov (United States)

    Davies, Marie L; Hopkins, Lee J; Halliday, Sue; Houston, Fiona; Hunter, Nora; McConnell, Ian

    2004-02-01

    Scrapie is a transmissible spongiform encephalopathy in which there is an accumulation of the abnormal form of the prion protein, PrPsc, in the lymphoreticular system and nervous system. There is a particular accumulation of PrPsc on follicular dendritic cells within the germinal centre of B-cell follicles. Because accumulation of PrPsc in the nervous system leads to neuronal cell loss we have examined PrPsc accumulation in the prescapular and mesenteric lymph nodes in relation to lymph node architecture of scrapie-challenged sheep. We demonstrate that an accumulation of PrPsc in the lymph node fails to result in gross defects in the microanatomy and phenotype of T- and B-cell areas in the lymph nodes. PMID:15027909

  6. A bovine cell line that can be infected by natural sheep scrapie prions.

    Directory of Open Access Journals (Sweden)

    Anja M Oelschlegel

    Full Text Available Cell culture systems represent a crucial part in basic prion research; yet, cell lines that are susceptible to prions, especially to field isolated prions that were not adapted to rodents, are very rare. The purpose of this study was to identify and characterize a cell line that was susceptible to ruminant-derived prions and to establish a stable prion infection within it. Based on species and tissue of origin as well as PrP expression rate, we pre-selected a total of 33 cell lines that were then challenged with natural and with mouse propagated BSE or scrapie inocula. Here, we report the successful infection of a non-transgenic bovine cell line, a sub-line of the bovine kidney cell line MDBK, with natural sheep scrapie prions. This cell line retained the scrapie infection for more than 200 passages. Selective cloning resulted in cell populations with increased accumulation of PrPres, although this treatment was not mandatory for retaining the infection. The infection remained stable, even under suboptimal culture conditions. The resulting infectivity of the cells was confirmed by mouse bioassay (Tgbov mice, Tgshp mice. We believe that PES cells used together with other prion permissive cell lines will prove a valuable tool for ongoing efforts to understand and defeat prions and prion diseases.

  7. A bovine cell line that can be infected by natural sheep scrapie prions.

    Science.gov (United States)

    Oelschlegel, Anja M; Geissen, Markus; Lenk, Matthias; Riebe, Roland; Angermann, Marlies; Schatzl, Herman; Schaetzl, Hermann; Groschup, Martin H

    2015-01-01

    Cell culture systems represent a crucial part in basic prion research; yet, cell lines that are susceptible to prions, especially to field isolated prions that were not adapted to rodents, are very rare. The purpose of this study was to identify and characterize a cell line that was susceptible to ruminant-derived prions and to establish a stable prion infection within it. Based on species and tissue of origin as well as PrP expression rate, we pre-selected a total of 33 cell lines that were then challenged with natural and with mouse propagated BSE or scrapie inocula. Here, we report the successful infection of a non-transgenic bovine cell line, a sub-line of the bovine kidney cell line MDBK, with natural sheep scrapie prions. This cell line retained the scrapie infection for more than 200 passages. Selective cloning resulted in cell populations with increased accumulation of PrPres, although this treatment was not mandatory for retaining the infection. The infection remained stable, even under suboptimal culture conditions. The resulting infectivity of the cells was confirmed by mouse bioassay (Tgbov mice, Tgshp mice). We believe that PES cells used together with other prion permissive cell lines will prove a valuable tool for ongoing efforts to understand and defeat prions and prion diseases.

  8. The prevalence of atypical scrapie in sheep from positive flocks is not higher than in the general sheep population in 11 European countries

    Directory of Open Access Journals (Sweden)

    Liam Barry

    2010-02-01

    Full Text Available Abstract Background During the last decade, active surveillance for transmissible spongiform encephalopathies in small ruminants has been intensive in Europe. In many countries this has led to the detection of cases of atypical scrapie which, unlike classical scrapie, might not be contagious. EU legislation requires, that following detection of a scrapie case, control measures including further testing take place in affected flocks, including the culling of genotype susceptible to classical scrapie. This might result in the detection of additional cases. The aim of this study was to investigate the occurrence of additional cases in flocks affected by atypical scrapie using surveillance data collected in Europe in order to ascertain whether atypical scrapie, is contagious. Results Questionnaires were used to collect, at national level, the results of active surveillance and testing associated with flock outbreaks in 12 European countries. The mean prevalence of atypical scrapie was 5.5 (5.0-6.0 cases per ten thousand in abattoir surveillance and 8.1 (7.3-9.0 cases per ten thousand in fallen stock. By using meta-analysis, on 11 out of the 12 countries, we found that the probability of detecting additional cases of atypical scrapie in positive flocks was similar to the probability observed in animals slaughtered for human consumption (odds ratio, OR = 1.07, CI95%: 0.70-1.63 or among fallen stock (OR = 0.78, CI95%: 0.51-1.2. In contrast, when comparing the two scrapie types, the probability of detecting additional cases in classical scrapie positive flocks was significantly higher than the probability of detecting additional cases in atypical scrapie positive flocks (OR = 32.4, CI95%: 20.7-50.7. Conclusions These results suggest that atypical scrapie is not contagious or has a very low transmissibility under natural conditions compared with classical scrapie. Furthermore this study stressed the importance of standardised data collection to make good

  9. 78 FR 25943 - Changes to Scrapie Flock Certification Program

    Science.gov (United States)

    2013-05-03

    ... Animal and Plant Health Inspection Service Changes to Scrapie Flock Certification Program AGENCY: Animal... giving notice of changes to the Scrapie Flock Certification Program (SFCP), a voluntary program for sheep and goat flock owners who wish to reduce and/or eliminate the risk of introducing classical...

  10. Establishment of the Method of Immunohistochemistry Assay for the Detection of Scrapie in Chinese Short-Tailed Han Sheep by Monoclonal Antibody

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The method of immunohistochemistry assay for the detection of scrapie in Chinese Short-tailed Han sheep was established using monoclonal antibody. Genomic DNA was isolated from Chinese Short-tailed Han sheep blood. Using the polymerase chain reaction technique, PrP27-30 gene sequence was amplified from Chinese Short-tailed Han sheep genomic DNA. By recombinant DNA technology, the recombinant protein of Chinese Short-tailed Han sheep PrP27-30 was obtained. Then, using standard methodology of myeloma cell fusion, a panel of monoclonal antibodies was generated. With mAbs, scrapie in Chinese Short-tailed Han sheep was detected by immunohistochemistry assay. The recombinant protein of Chinese Short-tailed Han sheep PrP27-30 was obtained and a panel of six hybridoma cell lines secreting specific antibodies to Chinese Short-tailed Han sheep PrP27-30 related to scrapie was obtained with one fusion between myeloma Sp2/0 and spleen cells from mice immunized with the purified recombinant protein. Four hybridoma cell lines can be used in immunohistochemistry assay for the detection of scrapie in Chinese Short-tailed Han sheep. So that the special monoclonal antibody developed in author's institute can be used to detect PrPsc of scrapie in Chinese Short-tailed Han sheep by immunohistochemistry in China.

  11. Membrane toxicity of abnormal prion protein in adrenal chromaffin cells of scrapie infected sheep.

    Directory of Open Access Journals (Sweden)

    Gillian McGovern

    Full Text Available Transmissible spongiform encephalopathies (TSEs or prion diseases are associated with accumulations of disease specific PrP (PrP(d in the central nervous system (CNS and often the lymphoreticular system (LRS. Accumulations have additionally been recorded in other tissues including the peripheral nervous system and adrenal gland. Here we investigate the effect of sheep scrapie on the morphology and the accumulation of PrP(d in the adrenal medulla of scrapie affected sheep using light and electron microscopy. Using immunogold electron microscopy, non-fibrillar forms of PrP(d were shown to accumulate mainly in association with chromaffin cells, occasional nerve endings and macrophages. PrP(d accumulation was associated with distinctive membrane changes of chromaffin cells including increased electron density, abnormal linearity and invaginations. Internalisation of PrP(d from the chromaffin cell plasma membrane occurred in association with granule recycling following hormone exocytosis. PrP(d accumulation and internalisation from membranes is similarly associated with perturbations of membrane structure and trafficking in CNS neurons and tingible body macrophages of the LRS. These data suggest that a major toxic effect of PrP(d is at the level of plasma membranes. However, the precise nature of PrP(d-membrane toxicity is tissue and cell specific suggesting that the normal protein may act as a multi-functional scaffolding molecule. We further suggest that the co-localisation of PrP(d with exocytic granules of the hormone trafficking system may provide an additional source of infectivity in blood.

  12. Caprine prion genen polymorphisms are associated with decreased incidence of classical scrapie in goat herds in the United Kingdom.

    NARCIS (Netherlands)

    Goldmann, W.; Ryan, K.; Stewart, P.; Parnham, D.; Xicohtencatl, R.; Fernandez, N.; Saunders, G.; Windl, O.; Gonzalez, L.; Bossers, A.

    2011-01-01

    The application of genetic breeding programmes to eradicate transmissible spongiform encephalopathies in goats is an important aim for reasons of animal welfare as well as human food safety and food security. Based on the positive impact of Prnp genetics on sheep scrapie in Europe in the past decade

  13. [From the Scrapie syndrome of sheep and goat to the mad cow disease - the history of the discovery of prion].

    Science.gov (United States)

    Liu, Rui; Weng, Yi

    2009-05-01

    Since the discovery of Scrapie Syndrome in sheep and goats in 1730, there emerged a series of diseases such as Creutzfeldt-Jakob disease, kuru disease and mad cow disease etc. In the research of kuru disease, the American scientist D. Carlteton Gajdusek found a new virus without the characteristic of DNA and RNA, which was awarded the Nobel Prize in physiology in 1976. Since then another American scientist, Stanley B. Prusiner, found a new virus-prion, taking protein as the genetic medium, which was awarded the Nobel prize in physiology and medicine in 1997. The discovery of prion is a great landmark in the research of life science, which laid a theoretical foundation for people to conquer a series of diseases such as Scrapie syndrome in sheep and goats, Creutzfeldt-Jakob disease, kuru disease and mad cow disease etc. PMID:19930927

  14. The effects of selective breeding against scrapie susceptibility on the genetic variability of the Latxa Black-Faced sheep breed

    OpenAIRE

    Legarra Andrés; Parada Analia; Alfonso Leopoldo; Ugarte Eva; Arana Ana

    2006-01-01

    Abstract Breeding sheep populations for scrapie resistance could result in a loss of genetic variability. In this study, the effect on genetic variability of selection for increasing the ARR allele frequency was estimated in the Latxa breed. Two sources of information were used, pedigree and genetic polymorphisms (fifteen microsatellites). The results based on the genealogical information were conditioned by a low pedigree completeness level that revealed the interest of also using the inform...

  15. Accumulation and dissemination of prion protein in experimental sheep scrapie in the natural host

    Directory of Open Access Journals (Sweden)

    Warner Richard

    2009-02-01

    Full Text Available Abstract Background In order to study the sites of uptake and mechanisms of dissemination of scrapie prions in the natural host under controlled conditions, lambs aged 14 days and homozygous for the VRQ allele of the PrP gene were infected by the oral route. Infection occurred in all lambs with a remarkably short and highly consistent incubation period of approximately 6 months. Challenge of lambs at approximately eight months of age resulted in disease in all animals, but with more variable incubation periods averaging significantly longer than those challenged at 14 days. This model provides an excellent system in which to study the disease in the natural host by virtue of the relatively short incubation period and close resemblance to natural infection. Results Multiple sites of prion uptake were identified, of which the most important was the Peyer's patch of the distal ileum. Neuroinvasion was detected initially in the enteric nervous system prior to infection of the central nervous system. At end stage disease prion accumulation was widespread throughout the entire neuraxis, but vacuolar pathology was absent in most animals that developed disease at 6–7 months of age. Conclusion Initial spread of detectable PrP was consistent with drainage in afferent lymph to dependent lymph nodes. Subsequent accumulation of prions in lymphoid tissue not associated with the gut is consistent with haematogenous spread. In addition to macrophages and follicular dendritic cells, prion containing cells consistent with afferent lymph dendritic cells were identified and are suggested as a likely vehicle for carriage of prions from initial site of uptake to the lymphoreticular system, and as potential carriers of prion protein in blood. It is apparent that spongiform change, the characteristic lesion of scrapie and other prion diseases, is not responsible for the clinical signs in sheep, but may develop in an age dependent manner.

  16. Diversity in neuroanatomical distribution of abnormal prion protein in atypical scrapie.

    Directory of Open Access Journals (Sweden)

    Alice Nentwig

    2007-06-01

    Full Text Available Scrapie is a transmissible spongiform encephalopathy (TSE in sheep and goats. In recent years, atypical scrapie cases were identified that differed from classical scrapie in the molecular characteristics of the disease-associated pathological prion protein (PrP(sc. In this study, we analyze the molecular and neuropathological phenotype of nine Swiss TSE cases in sheep and goats. One sheep was identified as classical scrapie, whereas six sheep, as well as two goats, were classified as atypical scrapie. The latter revealed a uniform electrophoretic mobility pattern of the proteinase K-resistant core fragment of PrP(sc distinct from classical scrapie regardless of the genotype, the species, and the neuroanatomical structure. Remarkably different types of neuroanatomical PrP(sc distribution were observed in atypical scrapie cases by both western immunoblotting and immunohistochemistry. Our findings indicate that the biodiversity in atypical scrapie is larger than expected and thus impacts on current sampling and testing strategies in small ruminant TSE surveillance.

  17. Scientific and technical assistance on the provisional results of the study on genetic resistance to Classical scrapie in goats in Cyprus

    Directory of Open Access Journals (Sweden)

    European Food Safety Authority

    2012-11-01

    Full Text Available This EFSA Scientific Report reviews and discusses the provisional results of a study (EURL/Cypriot study on genetic resistance to Classical scrapie in goats in Cyprus. It is concluded that the provisional results obtained in the study further support the lower susceptibility to Classical scrapie in goats carrying the D146 and S146 alleles compared to wild type (N146N goats. The results from intracerebral challenge are not compatible with a level of resistance as high as the one observed in sheep carrying the ARR allele or in goats carrying the K222 allele. Final results from the oral challenge will be crucial in determining the level of resistance associated with the D146 and S146 alleles. Furthermore, it is concluded that the provisional results obtained in the study are compatible with the possibility to use the D146 and S146 alleles to build a genetic strategy to control and eradicate Classical scrapie in goats in Cyprus. However, the success of such a strategy will be determined by the level of resistance associated with the D146 and S146 alleles against infection with all the different TSE agents proved to be circulating in Cyprus, which at this stage of the EURL/Cypriot study remains to be definitively assessed. In addition, as compared to the results of the model developed in the study, it is concluded that the efficiency of the implementation in the field of a breeding strategy selecting for the D146 and S146 alleles may be lower due to potential practical constraints related to the management of genetic diversity, to the selection for production and health traits and to the need of moving animals for breeding purposes in Cyprus. Recommendations on aspects that may be considered when completing the study are formulated.

  18. Caprine prion gene polymorphisms are associated with decreased incidence of classical scrapie in goat herds in the United Kingdom

    Directory of Open Access Journals (Sweden)

    Goldmann Wilfred

    2011-10-01

    Full Text Available Abstract The application of genetic breeding programmes to eradicate transmissible spongiform encephalopathies in goats is an important aim for reasons of animal welfare as well as human food safety and food security. Based on the positive impact of Prnp genetics on sheep scrapie in Europe in the past decade, we have established caprine Prnp gene variation in more than 1100 goats from the United Kingdom and studied the association of Prnp alleles with disease phenotypes in 150 scrapie-positive goats. This investigation confirms the association of the Met142 encoding Prnp allele with increased resistance to preclinical and clinical scrapie. It reveals a novel association of the Ser127 encoding allele with a reduced probability to develop clinical signs of scrapie in goats that are already positive for the accumulation of disease-specific prion protein in brain or periphery. A United Kingdom survey of Prnp genotypes in eight common breeds revealed eleven alleles in over thirty genotypes. The Met142 encoding allele had a high overall mean allele frequency of 22.6%, whereas the Ser127 encoding allele frequency was considerably lower with 6.4%. In contrast, a well known resistance associated allele encoding Lys222 was found to be rare (0.9% in this survey. The analysis of Prnp genotypes in Mexican Criollas goats revealed nine alleles, including a novel Phe to Leu substitution in codon 201, confirming that high genetic variability of Prnp can be found in scrapie-free populations. Our study implies that it should be feasible to lower scrapie prevalence in goat herds in the United Kingdom by genetic selection.

  19. A distinct proteinase K resistant prion protein fragment in goats with no signs of disease in a classical scrapie outbreak

    NARCIS (Netherlands)

    Bouzalas, I.; Lörtscher, F.; Dovas, C.; Oevermann, A.; Langeveld, J.P.M.; Papanastassopoulou, M.; Papadopoulos, O.; Zurbriggen, A.; Seuberlich, T.

    2011-01-01

    Considerable efforts have been directed toward the identification of small-ruminant prion diseases, i.e., classical and atypical scrapie as well as bovine spongiform encephalopathy (BSE). Here we report the in-depth molecular analysis of the proteinase K-resistant prion protein core fragment (PrPres

  20. Accumulation profiles of PrPSc in hemal nodes of naturally and experimentally scrapie-infected sheep

    OpenAIRE

    Dassanayake, Rohana P; Truscott, Thomas C; Özyiğit, M Özgür; Zhuang, Dongyue; Schneider, David A; O’Rourke, Katherine I.

    2013-01-01

    Background In classical scrapie, the disease-associated abnormal isoform (PrPSc) of normal prion protein accumulates principally in the nervous system and lymphoid tissues of small ruminants. Lymph nodes traffic leukocytes via lymphatic and blood vasculatures but hemal nodes lack lymphatic vessels and thus traffic leukocytes only via the blood. Although PrPSc accumulation profiles are well-characterized in ovine lymphoid tissues, there is limited information on such profiles in hemal nodes. T...

  1. Discovery of a novel, monocationic, small-molecule inhibitor of scrapie prion accumulation in cultured sheep microglia and rov cells PLoS one

    Science.gov (United States)

    Prion diseases, including sheep scrapie are neurodegenerative diseases with the fundamental pathogenesis involving conversion of normal cellular prion protein (PrPC) to disease-associated prion protein (PrPSc). An aromatic monocationic furamidine analogue (DB772), which has previously demonstrated a...

  2. Myenteric neurons of the ileum that express somatostatin are a target of prion neuroinvasion in an alimentary model of sheep scrapie

    Science.gov (United States)

    Scrapie disease is an orally transmissible spongiform encephalopathy disease of sheep in which the causative agent, the prion, can disseminate to the brain via nerves innervating the gut. Nerve cells intrinsic to the ileum (enteric neurons) are the first part of the peripheral nervous system invaded...

  3. A lympho-follicular microenvironment is required for pathological prion protein deposition in chronically inflamed tissues from scrapie-affected sheep.

    Science.gov (United States)

    Maestrale, Caterina; Di Guardo, Giovanni; Cancedda, Maria Giovanna; Marruchella, Giuseppe; Masia, Mariangela; Sechi, Stefania; Macciocu, Simonetta; Santucciu, Cinzia; Petruzzi, Mara; Ligios, Ciriaco

    2013-01-01

    In sheep scrapie, pathological prion protein (PrP(Sc)) deposition occurs in the lymphoreticular and central nervous systems. We investigated PrP(Sc) distribution in scrapie-affected sheep showing simultaneous evidence of chronic lymphofollicular, lymphoproliferative/non-lymphofollicular, and/or granulomatous inflammations in their mammary gland, lung, and ileum. To do this, PrP(Sc) detection was carried out via immunohistochemistry and Western Blotting techniques, as well as through inflammatory cell immunophenotyping. Expression studies of gene coding for biological factors modulating the host's inflammatory response were also carried out. We demonstrated that ectopic PrP(Sc) deposition occurs exclusively in the context of lymphofollicular inflammatory sites, inside newly formed and well-organized lymphoid follicles harboring follicular dendritic cells. On the contrary, no PrP(Sc) deposition was detected in granulomas, even when they were closely located to newly formed lymphoid follicles. A significantly more consistent expression of lymphotoxin α and β mRNA was detected in lymphofollicular inflammation compared to the other two types, with lymphotoxin α and β signaling new lymphoid follicles' formation and, likely, the occurrence of ectopic PrP(Sc) deposition inside them. Our findings suggest that, in sheep co-affected by scrapie and chronic inflammatory conditions, only newly formed lymphoid follicles provide a suitable micro-environment that supports the scrapie agent's replication in inflammatory sites, with an increased risk of prion shedding through body secretions/excretions. PMID:23658779

  4. A lympho-follicular microenvironment is required for pathological prion protein deposition in chronically inflamed tissues from scrapie-affected sheep.

    Directory of Open Access Journals (Sweden)

    Caterina Maestrale

    Full Text Available In sheep scrapie, pathological prion protein (PrP(Sc deposition occurs in the lymphoreticular and central nervous systems. We investigated PrP(Sc distribution in scrapie-affected sheep showing simultaneous evidence of chronic lymphofollicular, lymphoproliferative/non-lymphofollicular, and/or granulomatous inflammations in their mammary gland, lung, and ileum. To do this, PrP(Sc detection was carried out via immunohistochemistry and Western Blotting techniques, as well as through inflammatory cell immunophenotyping. Expression studies of gene coding for biological factors modulating the host's inflammatory response were also carried out. We demonstrated that ectopic PrP(Sc deposition occurs exclusively in the context of lymphofollicular inflammatory sites, inside newly formed and well-organized lymphoid follicles harboring follicular dendritic cells. On the contrary, no PrP(Sc deposition was detected in granulomas, even when they were closely located to newly formed lymphoid follicles. A significantly more consistent expression of lymphotoxin α and β mRNA was detected in lymphofollicular inflammation compared to the other two types, with lymphotoxin α and β signaling new lymphoid follicles' formation and, likely, the occurrence of ectopic PrP(Sc deposition inside them. Our findings suggest that, in sheep co-affected by scrapie and chronic inflammatory conditions, only newly formed lymphoid follicles provide a suitable micro-environment that supports the scrapie agent's replication in inflammatory sites, with an increased risk of prion shedding through body secretions/excretions.

  5. The effects of selective breeding against scrapie susceptibility on the genetic variability of the Latxa Black-Faced sheep breed

    Directory of Open Access Journals (Sweden)

    Legarra Andrés

    2006-09-01

    Full Text Available Abstract Breeding sheep populations for scrapie resistance could result in a loss of genetic variability. In this study, the effect on genetic variability of selection for increasing the ARR allele frequency was estimated in the Latxa breed. Two sources of information were used, pedigree and genetic polymorphisms (fifteen microsatellites. The results based on the genealogical information were conditioned by a low pedigree completeness level that revealed the interest of also using the information provided by the molecular markers. The overall results suggest that no great negative effect on genetic variability can be expected in the short time in the population analysed by selection of only ARR/ARR males. The estimated average relationship of ARR/ARR males with reproductive females was similar to that of all available males whatever its genotype: 0.010 vs. 0.012 for a genealogical relationship and 0.257 vs. 0.296 for molecular coancestry, respectively. However, selection of only ARR/ARR males implied important losses in founder animals (87 percent and low frequency alleles (30 percent in the ram population. The evaluation of mild selection strategies against scrapie susceptibility based on the use of some ARR heterozygous males was difficult because the genetic relationships estimated among animals differed when pedigree or molecular information was used, and the use of more molecular markers should be evaluated.

  6. Strain typing of classical scrapie by transgenic mouse bioassay using protein misfolding cyclic amplification to replace primary passage.

    Directory of Open Access Journals (Sweden)

    Katy E Beck

    Full Text Available According to traditional murine bioassay methodology, prions must be serially passaged within a new host before a stable phenotype, and therefore a strain, can be assigned. Prions often transmit with difficulty from one species to another; a property termed the transmission barrier. Transgenic mouse lines that over express prion protein (PrP genes of different species can circumvent the transmission barrier but serial passages may still be required, particularly if unknown strains are encountered. Here we sought to investigate whether protein misfolding cyclic amplification (PMCA, an in-vitro method of PrP(Sc replication, could be used to replace serial passage of VRQ/VRQ classical scrapie isolates undergoing strain typing in ovine transgenic tg338 mice. Two classical scrapie field isolates that do not readily transmit to wild-type mice underwent bioassay in tg338 mice pre- and post- PMCA and the phenotype of disease in inoculated mice was compared. For one of the sources investigated, the PMCA product gave rise to the same disease phenotypes in tg338 mice as traditional bioassay, as indicated by lesion profile, IHC analysis and Western blot, whilst the second source produced phenotypic characteristics which were not identical with those that arose through traditional bioassay. These data show that differences in the efficiency of PMCA as a strain-typing tool may vary between ovine classical scrapie isolates and therefore suggest that the ability of PMCA to replace serial passage of classical scrapie in tg338 mice may depend on the strain present in the initial source.

  7. Accumulation and dissemination of prion protein in experimental sheep scrapie in the natural host

    OpenAIRE

    Warner Richard; Heasman Lindsay; Dexter Glenda E; Ryder Stephen J; Moore S Jo

    2009-01-01

    Abstract Background In order to study the sites of uptake and mechanisms of dissemination of scrapie prions in the natural host under controlled conditions, lambs aged 14 days and homozygous for the VRQ allele of the PrP gene were infected by the oral route. Infection occurred in all lambs with a remarkably short and highly consistent incubation period of approximately 6 months. Challenge of lambs at approximately eight months of age resulted in disease in all animals, but with more variable ...

  8. Comparison of strategies for substantiating freedom from scrapie in a sheep flock

    OpenAIRE

    Ducrot Christian; Calavas Didier; Martinez Marie-José; Durand Benoit

    2009-01-01

    Abstract Background The public health threat represented by a potential circulation of bovine spongiform encephalopathy agent in sheep population has led European animal health authorities to launch large screening and genetic selection programmes. If demonstrated, such a circulation would have dramatic economic consequences for sheep breeding sector. In this context, it is important to evaluate the feasibility of qualification procedures that would allow sheep breeders demonstrating their fl...

  9. Prion Protein Gene Variability in Spanish Goats. Inference through Susceptibility to Classical Scrapie Strains and Pathogenic Distribution of Peripheral PrPsc

    Science.gov (United States)

    Acín, Cristina; Martín-Burriel, Inmaculada; Monleón, Eva; Lyahyai, Jaber; Pitarch, José Luis; Serrano, Carmen; Monzón, Marta; Zaragoza, Pilar; Badiola, Juan José

    2013-01-01

    Classical scrapie is a neurological disorder of the central nervous system (CNS) characterized by the accumulation of an abnormal, partially protease resistant prion protein (PrPsc) in the CNS and in some peripheral tissues in domestic small ruminants. Whereas the pathological changes and genetic susceptibility of ovine scrapie are well known, caprine scrapie has been less well studied. We report here a pathological study of 13 scrapie-affected goats diagnosed in Spain during the last 9 years. We used immunohistochemical and biochemical techniques to discriminate between classical and atypical scrapie and bovine spongiform encephalopathy (BSE). All the animals displayed PrPsc distribution patterns and western blot characteristics compatible with classical scrapie. In addition, we determined the complete open reading frame sequence of the PRNP in these scrapie-affected animals. The polymorphisms observed were compared with those of the herd mates (n = 665) and with the frequencies of healthy herds (n = 581) of native Spanish goats (Retinta, Pirenaica and Moncaina) and other worldwide breeds reared in Spain (Saanen, Alpine and crossbreed). In total, sixteen polymorphic sites were identified, including the known amino acid substitutions at codons G37V, G127S, M137I, I142M, H143R, R151H, R154H, R211Q, Q222K, G232W, and P240S, and new polymorphisms at codons G74D, M112T, R139S, L141F and Q215R. In addition, the known 42, 138 and 179 silent mutations were detected, and one new one is reported at codon 122. The genetic differences observed in the population studied have been attributed to breed and most of the novel polymorphic codons show frequencies lower than 5%. This work provides the first basis of polymorphic distribution of PRNP in native and worldwide goat breeds reared in Spain. PMID:23580248

  10. Eradication of scrapie with selective breeding: are we nearly there?

    Directory of Open Access Journals (Sweden)

    Davidse Aart

    2010-05-01

    Full Text Available Abstract Background Following EU decision 2003/100/EC Member States have recently implemented sheep breeding programmes to reduce the prevalence of sheep with TSE susceptible prion genotypes. The present paper investigates the progress of the breeding programme in the Netherlands. The PrP genotype frequencies were monitored through time using two sets of random samples: one set covers the years 2005 to 2008 and is taken from national surveillance programme; the other is taken from 168 random sheep farms in 2007. The data reveal that although the level of compliance to the breeding programme has been high, the frequency of susceptible genotypes varies substantially between farms. The 168 sheep farms are a subset of 689 farms participating in a postal survey inquiring about management and breeding strategies. This survey aimed to identify how much these strategies varied between farms, in order to inform assessment of the expected future progress towards eradication of classical scrapie. Results On the one hand, we found that compliance to the national breeding program has been high, and the frequency of resistant genotypes is expected to increase further in the next few years. On the other hand, we observed a large variation in prevalence of the scrapie resistant PrP genotype ARR between farms, implicating a large variation of genetic resistance between farms. Substantial between-flock differences in management and breeding strategies were found in the postal survey, suggesting considerable variation in risk of scrapie transmission between farms. Conclusions Our results show that although there has been a good progress in the breeding for scrapie resistance and the average farm-level scrapie susceptibility in the Netherlands has been significantly reduced, still a considerable proportion of farms contain high frequencies of susceptible genotypes in their sheep population. Since 2007 the breeding for genetic resistance is voluntarily again, and

  11. CD21-Positive Follicular Dendritic Cells: A Possible Source of PrPSc in Lymph Node Macrophages of Scrapie-Infected Sheep

    OpenAIRE

    Herrmann, Lynn M.; Cheevers, William P.; Davis, William C.; Knowles, Donald P.; O’Rourke, Katherine I.

    2003-01-01

    Natural sheep scrapie is a prion disease characterized by the accumulation of PrPSc in brain and lymphoid tissues. Previous studies suggested that lymph node macrophages and follicular dendritic cells (FDC) accumulate PrPSc. In this study, lymph nodes were analyzed for the presence of PrPSc and macrophage or FDC markers using dual immunohistochemistry. A monoclonal antibody (mAb) to the C-terminus of PrP reacted with CD172a+ macrophages and CD21+ FDC processes in secondary follicles. However,...

  12. Detection of PrPSc in Formalin Fixed Paraffin Embedded Tissue by Western Blot Differentiates Classical Scrapie, Nor98 Scrapie, and BSE

    Science.gov (United States)

    Transmissible spongiform encephalopathies including bovine spongiform encephalopathy and scrapie are fatal neurodegenerative disorders associated with the presence of an infectious abnormal isoform of normal mammalian proteins called prions (PrP**Sc). Identification of PrP**Sc in the CNS is typicall...

  13. Primary transmission of chronic wasting disease versus scrapie prions from small ruminants to transgenic mice expressing ovine or cervid prion protein.

    Science.gov (United States)

    Madsen-Bouterse, Sally A; Schneider, David A; Zhuang, Dongyue; Dassanayake, Rohana P; Balachandran, Aru; Mitchell, Gordon B; O'Rourke, Katherine I

    2016-09-01

    Development of mice expressing either ovine (Tg338) or cervid (TgElk) prion protein (PrP) have aided in characterization of scrapie and chronic wasting disease (CWD), respectively. Experimental inoculation of sheep with CWD prions has demonstrated the potential for interspecies transmission but, infection with CWD versus classical scrapie prions may be difficult to differentiate using validated diagnostic platforms. In this study, mouse bioassay in Tg338 and TgElk was utilized to evaluate transmission of CWD versus scrapie prions from small ruminants. Mice (≥5 per homogenate) were inoculated with brain homogenates from clinically affected sheep or goats with naturally acquired classical scrapie, white-tailed deer with naturally acquired CWD (WTD-CWD) or sheep with experimentally acquired CWD derived from elk (sheep-passaged-CWD). Survival time (time to clinical disease) and attack rates (brain accumulation of protease resistant PrP, PrPres) were determined. Inoculation with classical scrapie prions resulted in clinical disease and 100 % attack rates in Tg338, but no clinical disease at endpoint (>300 days post-inoculation, p.i.) and low attack rates (6.8 %) in TgElk. Inoculation with WTD-CWD prions yielded no clinical disease or brain PrPres accumulation in Tg338 at endpoint (>500 days p.i.), but rapid onset of clinical disease (~121 days p.i.) and 100 % attack rate in TgElk. Sheep-passaged-CWD resulted in transmission to both mouse lines with 100 % attack rates at endpoint in Tg338 and an attack rate of ~73 % in TgElk with some culled due to clinical disease. These primary transmission observations demonstrate the potential of bioassay in Tg338 and TgElk to help differentiate possible infection with CWD versus classical scrapie prions in sheep and goats.

  14. Epidemiological investigations on the potential transmissibility of a rare disease: the case of atypical scrapie in Great Britain.

    Science.gov (United States)

    Ortiz-Peláez, A; Arnold, M E; Vidal-Diez, A

    2016-07-01

    Multiple cases of atypical scrapie in the same holding and co-existence with classical scrapie have been reported in Great Britain. A two-stage simulation tool was developed by combining a sampling algorithm and a hierarchical Bayesian model to simulate the number of positive cases of atypical scrapie from: (i) random sampling and (ii) using the actual sampled population in Great Britain, being the output probability of detection of flocks with one and more cases. Cluster analysis was conducted to assess the level of geographical over- and under-sampling over the years. The probability of detecting at least two cases of atypical scrapie in the same holding is much lower in simulated random data than in simulated actual data for all scenarios. Sampling bias in the selection of sheep for testing led to multiple sampling from fewer but larger holdings, Scotland, and areas of Wales were under-sampled and the South-West and East of England oversampled. The pattern of atypical scrapie cases observed is unlikely to be explained by a multi-case event epidemiologically linked. The co-existence of classical and atypical scrapie is a rare event with 19 holdings detected in GB and does not suggest an epidemiological link between the two types of disease. PMID:26976340

  15. CD21-positive follicular dendritic cells: A possible source of PrPSc in lymph node macrophages of scrapie-infected sheep.

    Science.gov (United States)

    Herrmann, Lynn M; Cheevers, William P; Davis, William C; Knowles, Donald P; O'Rourke, Katherine I

    2003-04-01

    Natural sheep scrapie is a prion disease characterized by the accumulation of PrP(Sc) in brain and lymphoid tissues. Previous studies suggested that lymph node macrophages and follicular dendritic cells (FDC) accumulate PrP(Sc). In this study, lymph nodes were analyzed for the presence of PrP(Sc) and macrophage or FDC markers using dual immunohistochemistry. A monoclonal antibody (mAb) to the C-terminus of PrP reacted with CD172a+ macrophages and CD21+ FDC processes in secondary follicles. However, a PrP N-terminus-specific mAb reacted with CD21+ FDC processes but not CD172a+ macrophages in secondary follicles. Neither the PrP N-terminus nor C-terminus-specific mAb reacted with CD172a+ macrophages in the medulla. These results indicate that lymph node follicular macrophages acquire PrP(Sc) by phagocytosis of CD21+ FDC processes. The results also suggest that follicular macrophages have proteases that process full-length PrP(Sc) to N-terminally truncated PrP(Sc). PMID:12651600

  16. Differentiation of ruminant transmissible spongiform encephalopathy isolate types, including bovine spongiform encephalopathy and CH1641 scrapie.

    Science.gov (United States)

    Jacobs, J G; Sauer, M; van Keulen, L J M; Tang, Y; Bossers, A; Langeveld, J P M

    2011-01-01

    With increased awareness of the diversity of transmissible spongiform encephalopathy (TSE) strains in the ruminant population, comes an appreciation of the need for improved methods of differential diagnosis. Exposure to bovine spongiform encephalopathy (BSE) has been associated with the human TSE, variant Creutzfeldt-Jakob disease, emphasizing the necessity in distinguishing low-risk TSE types from BSE. TSE type discrimination in ruminants such as cattle, sheep, goats and deer, requires the application of several prion protein (PrP)-specific antibodies in parallel immunochemical tests on brain homogenates or tissue sections from infected animals. This study uses in a single incubation step, three PrP-specific antibodies and fluorescent Alexa dye-labelled anti-mouse Fabs on a Western blot. The usual amount of brain tissue needed is 0.5 mg. This multiplex application of antibodies directed towards three different PrP epitopes enabled differential diagnosis of all established main features of classical scrapie, BSE and Nor98-like scrapie in sheep and goats, as well as the currently known BSE types C, H and L in cattle. Moreover, due to an antibody-dependent dual PrP-banding pattern, for the first time CH1641 scrapie of sheep can be reliably discriminated from the other TSE isolate types in sheep. PMID:20943889

  17. Epidemiological analysis of data for scrapie in Great Britain

    NARCIS (Netherlands)

    Hagenaars, T.H.J.; Donnelly, C.; Ferguson, N.M.

    2006-01-01

    In recent years, the control or eradication of scrapie and any other transmissible spongiform encephalopathies (TSEs) possibly circulating in the sheep population has become a priority in Britain and elsewhere in Europe. A better understanding of the epidemiology of scrapie would greatly aid the dev

  18. Comparison of two automated immunohistochemical procedures for the diagnosis of scrapie in domestic sheep and chronic wasting disease in North American white-tailed deer (Odocoileus virginianus) and mule deer (Odocoileus hemionus).

    Science.gov (United States)

    Baszler, T V; Kiupel, M; Williams, E S; Thomsen, B V; Gidlewski, T; Montgomery, D L; O'Rourke, K I; Hall, S M

    2006-03-01

    Two commercially available automated immunohistochemistry platforms, Ventana NexES and DakoCytomation Autostainer Universal Staining System, were compared for diagnosing sheep scrapie and cervid chronic wasting disease. Both automated platforms used the same antiprion protein monoclonal primary antibodies, but different platform-specific linker and amplification reagents and procedures. Duplicate sections of brainstem (at the level of the obex) and lymphoid tissue (retropharyngeal lymph node or tonsil) from the same tissue block were immunostained for the comparison. Examination of 1,020 tissues from 796 sheep revealed 100% concordance of results between the Ventana NexES and DakoCytomation platforms for diagnosing sheep scrapie from lymphoid tissue (103/103 positive; 405/405 negative) and brainstem (120/120 positive; 392/392 negative). Similarly, examination of 1,008 tissues from 504 white-tailed deer revealed 100% concordance between the Ventana NexES and DakoCytomation platforms for diagnosing chronic wasting disease from lymphoid tissue (104/104 positive; 400/400 negative) and brainstem (104/104 positive; 400/400 negative). Examination of 1,152 tissues from 482 mule deer revealed a concordance of 98.6% in lymphoid tissue and 99.9% in brainstem between the Ventana NexES and DakoCytomation platforms for diagnosing chronic wasting disease. The results indicate equivalence or near equivalence between the DakoCytomation and Ventana NexES autostainer platforms for identification of the disease-associated prion protein (PrPd)-positive and PrPd-negative brain and lymphoid tissues in sheep, white-tailed deer, and mule deer.

  19. Investigation of a simple model for within-flock transmission of scrapie

    NARCIS (Netherlands)

    Hagenaars, T.J.; Windig, J.J.

    2015-01-01

    Genetic control programs for scrapie in sheep build on solid knowledge of how susceptibility to scrapie is modulated by the prion protein genotype at the level of an individual sheep. In order to satisfactorily analyze the effectivity of control programs at the population level, insight is needed at

  20. Sheep scrapie susceptibility-linked polymorphisms do not modulate the initial binding of cellular to disease-associated prion protein prior to conversion

    NARCIS (Netherlands)

    Rigter, A.; Bossers, A.

    2005-01-01

    Conversion of the host-encoded protease-sensitive cellular prion protein (PrPC) into the scrapie-associated protease-resistant isoform (PrPSc) of prion protein (PrP) is the central event in transmissible spongiform encephalopathies or prion diseases. Differences in transmissibility and susceptibilit

  1. RECTAL BIOPSY IN SHEEP AND GOATS FOR MONITORING AND ANTE-MORTEM DIAGNOSIS OF SCRAPIE: NUMBER OF LYMPHOID FOLLICLES IN TWO CONSECUTIVE COLLECTIONS

    Directory of Open Access Journals (Sweden)

    Helen Caroline Raksa

    2016-07-01

    O acúmulo da PrPSc em tecidos linfoides levou ao desenvolvimento de procedimentos de biopsia para o diagnóstico ante mortem da scrapie em ovinos, utilizando tecidos acessíveis como a tonsila(5 e terceira pálpebra(6, e a técnica de imuno-histoquímica (IHQ. Por outro lado, a grande área de folículos linfoides presente no reto de ovinos(7 tornou a biopsia retal uma possibilidade de diagnóstico ante mortem da scrapie. Amostras da mucosa retal têm sido colhidas e analisadas por meio de provas de IHQ para avaliar a presença de PrPSc no tecido linfoide associado à mucosa retoanal (RAMALT, do inglês Recto-Anal Mucosa Associated Lymphoid Tissue(8,9. No Brasil, o primeiro relato de scrapie foi em 1978, em um ovino Hampshire Down, importado da Inglaterra(10. Segundo a OIE, de 2008 a 2014 foram sacrificados 41 animais no país, em surtos de scra

  2. Salivary prions in sheep and deer

    OpenAIRE

    Tamgüney, Gültekin; Richt, Jürgen A; Hamir, Amir N.; Greenlee, Justin J.; Miller, Michael W.; Wolfe, Lisa L; Sirochman, Tracey M; Young, Alan J; Glidden, David V.; Johnson, Natrina L.; Giles, Kurt; Stephen J DeArmond; Prusiner, Stanley B.

    2012-01-01

    Scrapie of sheep and chronic wasting disease (CWD) of cervids are transmissible prion diseases. Milk and placenta have been identified as sources of scrapie prions but do not explain horizontal transmission. In contrast, CWD prions have been reported in saliva, urine and feces, which are thought to be responsible for horizontal transmission. While the titers of CWD prions have been measured in feces, levels in saliva or urine are unknown. Because sheep produce ∼17 L/day of saliva and scrapie ...

  3. Heart rate variability analysis in sheep affected by transmissible spongiform encephalopathies

    Directory of Open Access Journals (Sweden)

    Konold Timm

    2011-12-01

    Full Text Available Abstract Background The function of the autonomic nervous system can be assessed by determining heart rate variability (HRV, which is impaired in some brainstem diseases in humans. Transmissible spongiform encephalopathies (TSEs in sheep are diseases characterised by accumulation of disease-associated prion protein in the brainstem, including nuclei of the parasympathetic nervous system. This study was undertaken to assess whether analysis of HRV can be used as an aid in the diagnosis of TSEs in clinically affected, naturally or experimentally infected sheep. Findings When HRV indices were compared between 41 clinical TSE cases (18 sheep infected with scrapie and 23 sheep infected with bovine spongiform encephalopathy, 11 control sheep and six sheep reported as scrapie suspects or dosed with BSE brain homogenate, which were not confirmed as TSE cases by postmortem tests, no significant differences were found between the groups. Median heart rate was significantly different but only when sheep were grouped by gender: it was higher in female TSE cases than in control sheep and higher in female than castrated male ovine classical BSE cases. Conclusions HRV analysis was not useful as a diagnostic aid for TSEs of sheep.

  4. 从羊瘙痒症到疯牛病——朊病毒发现史%From the Scrapie Syndrome of sheep and goats to the mad cow disease-the history of the discovery of prion

    Institute of Scientific and Technical Information of China (English)

    刘锐; 翁屹

    2009-01-01

    从1730年人们发现羊瘙痒症开始,克-雅氏症、库鲁病、疯牛病等一系列疾病随之出现.在库鲁病的研究中,美国科学家盖达塞克发现其病原体不具有DNA或RNA特性,并因此获得了1976年的诺贝尔生理学医学奖.其后,另一位美国科学家普鲁塞纳在进一步研究中,发现了以蛋白质为遗传媒介的新型病毒--朊病毒,并因此获得了1997年诺贝尔生理学医学奖.朊病毒的发现是生命科学研究中的重大事件,为人类战胜羊瘙痒症、克-雅氏症、库鲁病和疯牛病等一系列疾病奠定了理论基础.%Since the discovery of Scrapie Syndrome in sheep and goats in 1730, there emerged a series of diseases such as Creutzfeldt-Jakob disease, kuru disease and mad cow disease etc. In the research of kuru disease, the American scientist D. Carlteton Gajdusek found a new virus without the characteristic of DNA and RNA, which was awarded the Nobel Prize in physiology in 1976. Since then another American sci-entist, Stanley B. Prusiner, found a new virus-prion, taking protein as the genetic medium, which was awar-ded the Nobel prize in physiology and medicine in 1997. The discovery of prion is a great landmark in the re-search of life science, which laid a theoretical foundation for people to conquer n series of diseases such as Scrapie syndrome in sheep and goats, Creutzfeldt-Jakob disease, kuru disease and mad cow disease etc.

  5. Association of PrP genotype with lamb production traits in four commercial breeds of British upland sheep

    OpenAIRE

    Boulton, Kay; Moore, R C; Bishop, S. C.

    2010-01-01

    Selection of sheep on PrP genotype to reduce risks of classical scrapie outbreaks is now widespread in the British sheep industry. However a recurring concern from breeders is that PrP genotype may be unfavourably associated with lamb performance. In this study we report the results from our investigations into this claim using performance data from 12,673 PrP genotyped lambs in four breeds of upland and crossing sheep: Beulah (4014), Blue Faced Leicester (725), Lleyn (5208) and North Country...

  6. Age, scrapie status, PrP genotype and follicular dendritic cells in ovine ileal Peyer's patches.

    Science.gov (United States)

    Marruchella, Giuseppe; Ligios, Ciriaco; Di Guardo, Giovanni

    2012-10-01

    Follicular dendritic cells (FDCs) residing within ileal Peyer's patches (PPs) are of crucial relevance for sheep scrapie early pathogenesis and subsequent scrapie prion neuroinvasion. In this study, ileal PP follicles were significantly more numerous in lambs than in adult Sarda breed sheep, with significant differences being also found in lymphoid follicle area, perimeter and FDC density. Furthermore, PrPd deposition within ileal PPs and host's PrP genotype did not significantly influence these parameters. We conclude that age significantly affects FDC density in ileal PPs from Sarda breed ovines, independently from host's scrapie status and PrP genotype. PMID:21962485

  7. hTERT-immortalized ovine microglia propagate natural scrapie isolates

    Science.gov (United States)

    Scrapie is a transmissible fatal neurodegenerative disease of sheep that is caused by a novel infectious agent called a prion. The study of prions under controlled culture conditions is crucial to advancing knowledge regarding prion processes of replication and accumulation within cells. Unfortunate...

  8. Pruritus is a common feature in sheep infected with the BSE agent

    Directory of Open Access Journals (Sweden)

    Jeffrey Martin

    2008-04-01

    Full Text Available Abstract Background The variability in the clinical or pathological presentation of transmissible spongiform encephalopathies (TSEs in sheep, such as scrapie and bovine spongiform encephalopathy (BSE, has been attributed to prion protein genotype, strain, breed, clinical duration, dose, route and type of inoculum and the age at infection. The study aimed to describe the clinical signs in sheep infected with the BSE agent throughout its clinical course to determine whether the clinical signs were as variable as described for classical scrapie in sheep. The clinical signs were compared to BSE-negative sheep to assess if disease-specific clinical markers exist. Results Forty-seven (34% of 139 sheep, which comprised 123 challenged sheep and 16 undosed controls, were positive for BSE. Affected sheep belonged to five different breeds and three different genotypes (ARQ/ARQ, VRQ/VRQ and AHQ/AHQ. None of the controls or BSE exposed sheep with ARR alleles were positive. Pruritus was present in 41 (87% BSE positive sheep; the remaining six were judged to be pre-clinically infected. Testing of the response to scratching along the dorsum of a sheep proved to be a good indicator of clinical disease with a test sensitivity of 85% and specificity of 98% and usually coincided with weight loss. Clinical signs that were displayed significantly earlier in BSE positive cases compared to negative cases were behavioural changes, pruritic behaviour, a positive scratch test, alopecia, skin lesions, teeth grinding, tremor, ataxia, loss of weight and loss of body condition. The frequency and severity of each specific clinical sign usually increased with the progression of disease over a period of 16–20 weeks. Conclusion Our results suggest that BSE in sheep presents with relatively uniform clinical signs, with pruritus of increased severity and abnormalities in behaviour or movement as the disease progressed. Based on the studied sheep, these clinical features appear to

  9. Scrapie prion liposomes and rods exhibit target sizes of 55,000 Da

    International Nuclear Information System (INIS)

    Scrapie is a degenerative neurologic disease in sheep and goats which can be experimentally transmitted to laboratory rodents. Considerable evidence suggests that the scrapie agent is composed largely, if not entirely, of an abnormal isoform of the prion protein (PrPSc). Inactivation of scrapie prions by ionizing radiation exhibited single-hit kinetics and gave a target size of 55,000 +/- 9000 mol wt. The inactivation profile was independent of the form of the prion. Scrapie agent infectivity in brain homogenates, microsomal fractions, detergent-extracted microsomes, purified amyloid rods, and liposomes exhibited the same inactivation profile. Our data are consistent with the hypothesis that the infectious particle causing scrapie contains approximately 2 PrPSc molecules

  10. In vitro prion protein conversion suggests risk of bighorn sheep (Ovis canadensis) to transmissible spongiform encephalopathies

    Science.gov (United States)

    Johnson, Christopher J.; Morawski, A.R.; Carlson, C.M.; Chang, H.

    2013-01-01

    Background: Transmissible spongiform encephalopathies (TSEs) affect both domestic sheep (scrapie) and captive and free-ranging cervids (chronic wasting disease; CWD). The geographical range of bighorn sheep (Ovis canadensis; BHS) overlaps with states or provinces that have contained scrapie-positive sheep or goats and areas with present epizootics of CWD in cervids. No TSEs have been documented in BHS, but the susceptibility of this species to TSEs remains unknown. Results: We acquired a library of BHS tissues and found no evidence of preexisting TSEs in these animals. The prion protein gene (Prnp) in all BHS in our library was identical to scrapie-susceptible domestic sheep (A136R 154Q171). Using an in vitro prion protein conversion assay, which has been previously used to assess TSE species barriers and, in our study appears to recollect known species barriers in mice, we assessed the potential transmissibility of TSEs to BHS. As expected based upon Prnp genotype, we observed BHS prion protein conversion by classical scrapie agent and evidence for a species barrier between transmissible mink encephalopathy (TME) and BHS. Interestingly, our data suggest that the species barrier of BHS to white-tailed deer or wapiti CWD agents is likely low. We also used protein misfolding cyclic amplification to confirm that CWD, but not TME, can template prion protein misfolding in A136R 154Q171genotype sheep. Conclusions: Our results indicate the in vitro conversion assay used in our study does mimic the species barrier of mice to the TSE agents that we tested. Based on Prnp genotype and results from conversion assays, BHS are likely to be susceptible to infection by classical scrapie. Despite mismatches in amino acids thought to modulate prion protein conversion, our data indicate that A136R154Q171 genotype sheep prion protein is misfolded by CWD agent, suggesting that these animals could be susceptible to CWD. Further investigation of TSE transmissibility to BHS, including

  11. Minder BSE en scrapie

    NARCIS (Netherlands)

    Zijderveld, van F.G.

    2011-01-01

    De dierziekte BSE is gevaarlijk voor de mens. Onderzoekers van het Central Veterinary Institute (CVI) hebben daarom snelle diagnostische tests ontwikkeld en ingezet bij rundvee, schapen en geiten. Ook hebben ze ervoor gezorgd dat schapen minder vatbaar zijn voor de verwante prionziekte scrapie.

  12. Atypical scrapie isolates involve a uniform prion species with a complex molecular signature.

    Directory of Open Access Journals (Sweden)

    Dorothea R Götte

    Full Text Available The pathobiology of atypical scrapie, a prion disease affecting sheep and goats, is still poorly understood. In a previous study, we demonstrated that atypical scrapie affecting small ruminants in Switzerland differs in the neuroanatomical distribution of the pathological prion protein (PrP(d. To investigate whether these differences depend on host-related vs. pathogen-related factors, we transmitted atypical scrapie to transgenic mice over-expressing the ovine prion protein (tg338. The clinical, neuropathological, and molecular phenotype of tg338 mice is similar between mice carrying the Swiss atypical scrapie isolates and the Nor98, an atypical scrapie isolate from Norway. Together with published data, our results suggest that atypical scrapie is caused by a uniform type of prion, and that the observed phenotypic differences in small ruminants are likely host-dependant. Strikingly, by using a refined SDS-PAGE technique, we established that the prominent proteinase K-resistant prion protein fragment in atypical scrapie consists of two separate, unglycosylated peptides with molecular masses of roughly 5 and 8 kDa. These findings show similarities to those for other prion diseases in animals and humans, and lay the groundwork for future comparative research.

  13. Transmission of scrapie prions to primate after an extended silent incubation period

    OpenAIRE

    Emmanuel E Comoy; Mikol, Jacqueline; Luccantoni-Freire, Sophie; Correia, Evelyne; Lescoutra-Etchegaray, Nathalie; Durand, Valérie; Dehen, Capucine; Andreoletti, Olivier; Casalone, Cristina; Richt, Juergen A.; Greenlee, Justin J.; Baron, Thierry; Benestad, Sylvie L.; Brown, Paul; Deslys, Jean-Philippe

    2015-01-01

    Classical bovine spongiform encephalopathy (c-BSE) is the only animal prion disease reputed to be zoonotic, causing variant Creutzfeldt-Jakob disease (vCJD) in humans and having guided protective measures for animal and human health against animal prion diseases. Recently, partial transmissions to humanized mice showed that the zoonotic potential of scrapie might be similar to c-BSE. We here report the direct transmission of a natural classical scrapie isolate to cynomolgus macaque, a highly ...

  14. Atypical/Nor98 scrapie in the Basque Country: a case report of eight outbreaks

    Directory of Open Access Journals (Sweden)

    Minguijón Esmeralda

    2010-03-01

    Full Text Available Abstract Background Since 2002, an active surveillance program for transmissible spongiform encephalopathy in small ruminants in European Union countries allowed identification of a considerable number of atypical cases with similarities to the previously identified atypical scrapie cases termed Nor98. Case presentation Here we report molecular and neuropathological features of eight atypical/Nor98 scrapie cases detected between 2002 and 2009. Significant features of the affected sheep included: their relatively high ages (mean age 7.9 years, range between 4.3 and 12.8, their breed (all Latxa and their PRNP genotypes (AFRQ/ALRQ, ALRR/ALRQ, AFRQ/AFRQ, AFRQ/AHQ, ALRQ/ALRH, ALRQ/ALRQ. All the sheep were confirmed as atypical scrapie by immunohistochemistry and immunoblotting. Two cases presented more PrP immunolabelling in cerebral cortex than in cerebellum. Conclusions This work indicates that atypical scrapie constitutes the most common small ruminant transmissible spongiform encephalopathy form in Latxa sheep in the Spanish Basque Country. Moreover, a new genotype (ALRQ/ALRH was found associated to atypical scrapie.

  15. Insights into the role of “prion-like” genes and proteins on scrapie susceptibility and ram fertility

    OpenAIRE

    Pimenta, Jorge Manuel Botelho Garcia Andrade

    2013-01-01

    Tese de Douoramento em Ciências Veterinárias. Especialidade de Produção Animal The established association between polymorphisms of prnp prion gene and susceptibility to scrapie disease in sheep prompted the development of breeding programmes aimed at increasing the natural resistance to scrapie in the European Union. In order to study the possible undesirable consequences from the widespread selection for the prnp genotype on ovine genetic diversity and reproduction, we primarily focused ...

  16. Gene Expression Profiling and Association with Prion-Related Lesions in the Medulla Oblongata of Symptomatic Natural Scrapie Animals

    Science.gov (United States)

    Filali, Hicham; Martin-Burriel, Inmaculada; Harders, Frank; Varona, Luis; Lyahyai, Jaber; Zaragoza, Pilar; Pumarola, Martí; Badiola, Juan J.; Bossers, Alex; Bolea, Rosa

    2011-01-01

    The pathogenesis of natural scrapie and other prion diseases remains unclear. Examining transcriptome variations in infected versus control animals may highlight new genes potentially involved in some of the molecular mechanisms of prion-induced pathology. The aim of this work was to identify disease-associated alterations in the gene expression profiles of the caudal medulla oblongata (MO) in sheep presenting the symptomatic phase of natural scrapie. The gene expression patterns in the MO from 7 sheep that had been naturally infected with scrapie were compared with 6 controls using a Central Veterinary Institute (CVI) custom designed 4×44K microarray. The microarray consisted of a probe set on the previously sequenced ovine tissue library by CVI and was supplemented with all of the Ovis aries transcripts that are currently publicly available. Over 350 probe sets displayed greater than 2-fold changes in expression. We identified 148 genes from these probes, many of which encode proteins that are involved in the immune response, ion transport, cell adhesion, and transcription. Our results confirm previously published gene expression changes that were observed in murine models with induced scrapie. Moreover, we have identified new genes that exhibit differential expression in scrapie and could be involved in prion neuropathology. Finally, we have investigated the relationship between gene expression profiles and the appearance of the main scrapie-related lesions, including prion protein deposition, gliosis and spongiosis. In this context, the potential impacts of these gene expression changes in the MO on scrapie development are discussed. PMID:21629698

  17. Distinct spatial activation of intrinsic and extrinsic apoptosis pathways in natural scrapie: association with prion-related lesions

    Science.gov (United States)

    Serrano, Carmen; Lyahyai, Jaber; Bolea, Rosa; Varona, Luis; Monleón, Eva; Badiola, Juan J.; Zaragoza, Pilar; Martín-Burriel, Inmaculada

    2009-01-01

    Neurodegeneration and gliosis are the main neuropathological features of prion diseases. However, the molecular mechanisms involved in these processes remain unclear. Several studies have demonstrated changes in the expression of apoptotic factors and inflammatory cytokines in animals with experimental infection. Here we present the expression profiles of 15 genes implicated in the intrinsic and extrinsic apoptotic pathways in the central nervous systems of sheep naturally infected with scrapie. Expression changes obtained by real-time RT-PCR were also compared with the extent of classical scrapie lesions, such as prion deposition, neuronal vacuolisation, spongiosis, and astrogliosis as well as with the activation of caspase-3, using a stepwise regression. The results suggest that the factors assessed participate in apoptotic or inflammatory functions, depending on the affected area. The mitochondrial apoptosis pathway was associated with prion deposition in the prefrontal cortex (the less affected area), and with activation of caspase-3-mediated cell death via over-expression of BAK. In addition to its known association with astroglial activation, the extrinsic apoptosis pathway was also related to cell death and neuronal vacuolisation. PMID:19401142

  18. Resistance of neonatal mice to scrapie is associated with inefficient infection of the immature spleen.

    Science.gov (United States)

    Ierna, Michelle; Farquhar, Christine F; Outram, George W; Bruce, Moira E

    2006-01-01

    Previous studies demonstrated that neonatal mice up to about a week old are less susceptible than adult mice to infection by intraperitoneal inoculation with mouse-passaged scrapie. In peripherally inoculated adult mice, scrapie replicates in lymphoid tissues such as the spleen before invading the central nervous system. Here, we investigated scrapie susceptibility in neonatal mice in more detail, concentrating on spleen involvement. First, we demonstrated that neonatal mice are about 10 times less susceptible than adults to intraperitoneal scrapie inoculation. Then we injected mice intraperitoneally with a scrapie dose that produced disease in all mice inoculated at 10 days or older but in only about a third of neonatally inoculated mice. In this experiment, spleens collected 70 days after scrapie injection of mice 10 days old or older almost all contained pathological prion protein, PrPSc, and those that were bioassayed all contained high infectivity levels. In contrast, at this early stage, only two of six spleens from neonatally inoculated mice had detectable, low infectivity levels; no PrPSc was detected, even in the two spleens. Therefore, neonatal mice have an impaired ability to replicate scrapie in their spleens, suggesting that replication sites are absent or sparse at birth but mature within 10 days. The increase in susceptibility with age correlated with the first immunocytochemical detection of the normal cellular form of prion protein, PrPc, on maturing follicular dendritic cell networks. As lymphoid tissues are more mature at birth in sheep, cattle, and humans than in mice, our results suggest that in utero infection with scrapie-like agents is theoretically possible in these species. PMID:16352571

  19. The "Ram Effect": A "Non-Classical" Mechanism for Inducing LH Surges in Sheep.

    Science.gov (United States)

    Fabre-Nys, Claude; Chanvallon, Audrey; Dupont, Joëlle; Lardic, Lionel; Lomet, Didier; Martinet, Stéphanie; Scaramuzzi, Rex J

    2016-01-01

    During spring sheep do not normally ovulate but exposure to a ram can induce ovulation. In some ewes an LH surge is induced immediately after exposure to a ram thus raising questions about the control of this precocious LH surge. Our first aim was to determine the plasma concentrations of oestradiol (E2) E2 in anoestrous ewes before and after the "ram effect" in ewes that had a "precocious" LH surge (starting within 6 hours), a "normal" surge (between 6 and 28h) and "late» surge (not detected by 56h). In another experiment we tested if a small increase in circulating E2 could induce an LH surge in anoestrus ewes. The concentration of E2 significantly was not different at the time of ram introduction among ewes with the three types of LH surge. "Precocious" LH surges were not preceded by a large increase in E2 unlike "normal" surges and small elevations of circulating E2 alone were unable to induce LH surges. These results show that the "precocious" LH surge was not the result of E2 positive feedback. Our second aim was to test if noradrenaline (NA) is involved in the LH response to the "ram effect". Using double labelling for Fos and tyrosine hydroxylase (TH) we showed that exposure of anoestrous ewes to a ram induced a higher density of cells positive for both in the A1 nucleus and the Locus Coeruleus complex compared to unstimulated controls. Finally, the administration by retrodialysis into the preoptic area, of NA increased the proportion of ewes with an LH response to ram odor whereas treatment with the α1 antagonist Prazosin decreased the LH pulse frequency and amplitude induced by a sexually active ram. Collectively these results suggest that in anoestrous ewes NA is involved in ram-induced LH secretion as observed in other induced ovulators.

  20. EFSA BIOHAZ Panel (EFSA Panel on Biological Hazards), 2014. Scientific Opinion on the scrapie situation in the EU after 10 years of monitoring and control in sheep and goats

    DEFF Research Database (Denmark)

    Hald, Tine; Baggesen, Dorte Lau

    of breeding programmes for resistance to CS (BP-CS) in the dissemination of resistance into the general sheep population has been assessed for those countries for which the CS trend analysis has been performed. CS in sheep was reported in 17 MSs (average prevalence: 8.7 cases/10 000 tests), with heterogeneous...... trends and geographical distribution: among the 13 countries reporting a consistent number of cases, the trend analysis shows a statistically significant decreasing trend only for six of them. Variations in the implementation of genetic and non-genetic measures for the control of CS may explain...... the failure to improve the disease situation in the remaining seven MSs. At a national level, a reduction in CS seems to be linked to better-achieving BP-CSs. Control options applied to CS in sheep and goats indicate that a CS eradication policy that relies solely on the detection of infected flocks by post...

  1. Role of Plasminogen in Propagation of Scrapie

    OpenAIRE

    Salmona, Mario; Capobianco, Raffaella; Colombo, Laura; De Luigi, Ada; Rossi, Giacomina; Mangieri, Michela; Giaccone, Giorgio; Quaglio, Elena; Chiesa, Roberto; Donati, Maria Benedetta; Tagliavini, Fabrizio; Forloni, Gianluigi

    2005-01-01

    To investigate whether plasminogen may feature in scrapie infection, we inoculated plasminogen-deficient (Plg−/−), heterozygous plasminogen-deficient (Plg+/−), and wild-type (Plg+/+) mice by the intracerebral or intraperitoneal (i.p.) route with the RML scrapie strain and monitored the onset of neurological signs of disease, survival time, brain, and accumulation of scrapie disease-associated forms of the prion protein (PrPSc). Only after i.p. inoculation, a slight, although significant, diff...

  2. Scrapie Affects the Maturation Cycle and Immune Complex Trapping by Follicular Dendritic Cells in Mice

    OpenAIRE

    Gillian McGovern; Neil Mabbott; Martin Jeffrey

    2009-01-01

    Transmissible spongiform encephalopathies (TSEs) or prion diseases are infectious neurological disorders of man and animals, characterised by abnormal disease-associated prion protein (PrP(d)) accumulations in the brain and lymphoreticular system (LRS). Prior to neuroinvasion, TSE agents often accumulate to high levels within the LRS, apparently without affecting immune function. However, our analysis of scrapie-affected sheep shows that PrP(d) accumulations within the LRS are associated with...

  3. The evaluation of exposure risks for natural transmission of scrapie within an infected flock

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    Davis Andrew

    2009-10-01

    Full Text Available Abstract Background Although the epidemiology of scrapie has been broadly understood for many years, attempts to introduce voluntary or compulsory controls to eradicate the disease have frequently failed. Lack of precision in defining the risk factors on farm has been one of the challenges to designing control strategies. This study attempted to define which parts of the annual flock management cycle represented the greatest risk of infection to naive lambs exposed to the farm environment at different times. Results In VRQ/VRQ lambs exposed to infected sheep at pasture or during lambing, and exposed to the buildings in which lambing took place, the attack rate was high and survival times were short. Where exposure was to pasture alone the number of sheep affected in each experimental group was reduced, and survival times were longer and related to length of exposure. Conclusion At the flock level, eradication and control strategies for scrapie must take into account the need to decontaminate buildings used for lambing, and to reduce (or prevent the exposure of lambs to infected sheep, especially in the later stages of incubation, and at lambing. The potential for environmental contamination from pasture should also be considered. Genotype selection may still prove to be the only viable tool to prevent infection from contaminated pasture, reduce environmental contamination and limit direct transmission from sheep to sheep.

  4. Prions in milk from ewes incubating natural scrapie.

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    Caroline Lacroux

    2008-12-01

    Full Text Available Since prion infectivity had never been reported in milk, dairy products originating from transmissible spongiform encephalopathy (TSE-affected ruminant flocks currently enter unrestricted into the animal and human food chain. However, a recently published study brought the first evidence of the presence of prions in mammary secretions from scrapie-affected ewes. Here we report the detection of consistent levels of infectivity in colostrum and milk from sheep incubating natural scrapie, several months prior to clinical onset. Additionally, abnormal PrP was detected, by immunohistochemistry and PET blot, in lacteal ducts and mammary acini. This PrP(Sc accumulation was detected only in ewes harbouring mammary ectopic lymphoid follicles that developed consequent to Maedi lentivirus infection. However, bioassay revealed that prion infectivity was present in milk and colostrum, not only from ewes with such lympho-proliferative chronic mastitis, but also from those displaying lesion-free mammary glands. In milk and colostrum, infectivity could be recovered in the cellular, cream, and casein-whey fractions. In our samples, using a Tg 338 mouse model, the highest per ml infectious titre measured was found to be equivalent to that contained in 6 microg of a posterior brain stem from a terminally scrapie-affected ewe. These findings indicate that both colostrum and milk from small ruminants incubating TSE could contribute to the animal TSE transmission process, either directly or through the presence of milk-derived material in animal feedstuffs. It also raises some concern with regard to the risk to humans of TSE exposure associated with milk products from ovine and other TSE-susceptible dairy species.

  5. Murine scrapie infection causes an abnormal germinal centre reaction in the spleen.

    Science.gov (United States)

    McGovern, G; Brown, K L; Bruce, M E; Jeffrey, M

    2004-01-01

    Follicular dendritic cells (FDCs) of the lymphoreticular system play a role in the peripheral replication of prion proteins in some transmissible spongiform encephalopathies (TSEs), including experimental murine scrapie models. Disease-specific PrP (PrPd) accumulation occurs in association with the plasmalemma and extracellular space around FDC dendrites, but no specific immunological response has yet been reported in animals affected by TSEs. In the present study, morphology (light microscopical and ultrastructural) of secondary lymphoid follicles of the spleen were examined in mice infected with the ME7 strain of scrapie and in uninfected control mice, with or without immunological stimulation with sheep red blood cells (SRBCs), at 70 days post-inoculation or at the terminal stage of disease (268 days). Scrapie infection was associated with hypertrophy of FDC dendrites, increased retention of electron-dense material at the FDC plasma membrane, and increased maturation and numbers of B lymphocytes within secondary follicles. FDC hypertrophy was particularly conspicuous in immune-stimulated ME7-infected mice. The electron-dense material was associated with PrP Napoli accumulation, as determined by immunogold labelling. We hypothesize that immune system changes are associated with increased immune complex trapping by hypertrophic FDCs expressing PrP Napoli molecules at the plasmalemma of dendrites, and that this process is exaggerated by immune system stimulation. Contrary to previous dogma, these results show that a pathological response within the immune system follows scrapie infection. PMID:15003476

  6. Scrapie Agent (Strain 263K) Can Transmit Disease via the Oral Route after Persistence in Soil over Years

    Science.gov (United States)

    Groschup, Martin H.; Peters, Rainer; Beekes, Michael; Terytze, Konstantin

    2007-01-01

    The persistence of infectious biomolecules in soil constitutes a substantial challenge. This holds particularly true with respect to prions, the causative agents of transmissible spongiform encephalopathies (TSEs) such as scrapie, bovine spongiform encephalopathy (BSE), or chronic wasting disease (CWD). Various studies have indicated that prions are able to persist in soil for years without losing their pathogenic activity. Dissemination of prions into the environment can occur from several sources, e.g., infectious placenta or amniotic fluid of sheep. Furthermore, environmental contamination by saliva, excrements or non-sterilized agricultural organic fertilizer is conceivable. Natural transmission of scrapie in the field seems to occur via the alimentary tract in the majority of cases, and scrapie-free sheep flocks can become infected on pastures where outbreaks of scrapie had been observed before. These findings point to a sustained contagion in the environment, and notably the soil. By using outdoor lysimeters, we simulated a contamination of standard soil with hamster-adapted 263K scrapie prions, and analyzed the presence and biological activity of the soil-associated PrPSc and infectivity by Western blotting and hamster bioassay, respectively. Our results showed that 263K scrapie agent can persist in soil at least over 29 months. Strikingly, not only the contaminated soil itself retained high levels of infectivity, as evidenced by oral administration to Syrian hamsters, but also feeding of aqueous soil extracts was able to induce disease in the reporter animals. We could also demonstrate that PrPSc in soil, extracted after 21 months, provides a catalytically active seed in the protein misfolding cyclic amplification (PMCA) reaction. PMCA opens therefore a perspective for considerably improving the detectability of prions in soil samples from the field. PMID:17502917

  7. Scrapie transmits to white-tailed deer by the oral route and has a molecular profile similar to chronic wasting disease

    Science.gov (United States)

    The purpose of this work was to determine susceptibility of white-tailed deer (WTD) to the agent of sheep scrapie and to compare the resultant PrPSc to that of the original inoculum and chronic wasting disease (CWD). We inoculated WTD by a natural route of exposure (concurrent oral and intranasal (I...

  8. Role of plasminogen in propagation of scrapie.

    Science.gov (United States)

    Salmona, Mario; Capobianco, Raffaella; Colombo, Laura; De Luigi, Ada; Rossi, Giacomina; Mangieri, Michela; Giaccone, Giorgio; Quaglio, Elena; Chiesa, Roberto; Donati, Maria Benedetta; Tagliavini, Fabrizio; Forloni, Gianluigi

    2005-09-01

    To investigate whether plasminogen may feature in scrapie infection, we inoculated plasminogen-deficient (Plg(-/-)), heterozygous plasminogen-deficient (Plg(+/-)), and wild-type (Plg(+/+)) mice by the intracerebral or intraperitoneal (i.p.) route with the RML scrapie strain and monitored the onset of neurological signs of disease, survival time, brain, and accumulation of scrapie disease-associated forms of the prion protein (PrP(Sc)). Only after i.p. inoculation, a slight, although significant, difference in survival (P follicular dendritic or lymphoid cells in Plg(-/-) mice. Once the disease progressed and mice began to die of infection, differences were no longer apparent in either brains or spleens. In conclusion, our data indicate that plasminogen has no major effect on the survival of scrapie agent-infected mice. PMID:16103174

  9. Tumor Necrosis Factor Alpha-Deficient, but Not Interleukin-6-Deficient, Mice Resist Peripheral Infection with Scrapie

    OpenAIRE

    Mabbott, Neil; Williams, Alun; Farquhar, Christine; Pasparakis, Manolis; Kollias, Giorgos; Bruce, Moira

    2000-01-01

    In most peripheral infections of rodents and sheep with scrapie, infectivity is found first in lymphoid tissues and later in the central nervous system (CNS). Cells within the germinal centers (GCs) of the spleen and lymph nodes are important sites of extraneural replication, from which infection is likely to spread to the CNS along peripheral nerves. Here, using immunodeficient mice, we investigate the identity of the cells in the spleen that are important for disease propagation. Despite po...

  10. 9 CFR 93.435 - Sheep and goats.

    Science.gov (United States)

    2010-01-01

    ... plasm from a region other than Australia, Canada, New Zealand, or the United States, in accordance with...) Except as provided in paragraph (b) of this section, all sheep and goats imported into the United States must be placed in a flock or herd in the United States that participates in the Voluntary Scrapie...

  11. White blood cell-based detection of asymptomatic scrapie infection by ex vivo assays.

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    Sophie Halliez

    Full Text Available Prion transmission can occur by blood transfusion in human variant Creutzfeldt-Jakob disease and in experimental animal models, including sheep. Screening of blood and its derivatives for the presence of prions became therefore a major public health issue. As infectious titer in blood is reportedly low, highly sensitive and robust methods are required to detect prions in blood and blood derived products. The objectives of this study were to compare different methods--in vitro, ex vivo and in vivo assays--to detect prion infectivity in cells prepared from blood samples obtained from scrapie infected sheep at different time points of the disease. Protein misfolding cyclic amplification (PMCA and bioassays in transgenic mice expressing the ovine prion protein were the most efficient methods to identify infected animals at any time of the disease (asymptomatic to terminally-ill stages. However scrapie cell and cerebellar organotypic slice culture assays designed to replicate ovine prions in culture also allowed detection of prion infectivity in blood cells from asymptomatic sheep. These findings confirm that white blood cells are appropriate targets for preclinical detection and introduce ex vivo tools to detect blood infectivity during the asymptomatic stage of the disease.

  12. Gene expression alterations in brains of mice infected with three strains of scrapie

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    Race Richard E

    2006-05-01

    Full Text Available Abstract Background Transmissible spongiform encephalopathies (TSEs or prion diseases are fatal neurodegenerative disorders which occur in humans and various animal species. Examples include Creutzfeldt-Jakob disease (CJD in humans, bovine spongiform encephalopathy (BSE in cattle, chronic wasting disease (CWD in deer and elk, and scrapie in sheep, and experimental mice. To gain insights into TSE pathogenesis, we made and used cDNA microarrays to identify disease-associated alterations in gene expression. Brain gene expression in scrapie-infected mice was compared to mock-infected mice at pre-symptomatic and symptomatic time points. Three strains of mouse scrapie that show striking differences in neuropathology were studied: ME7, 22L, and Chandler/RML. Results In symptomatic mice, over 400 significant gene expression alterations were identified. In contrast, only 22 genes showed significant alteration in the pre-symptomatic animals. We also identified genes that showed significant differences in alterations in gene expression between strains. Genes identified in this study encode proteins that are involved in many cellular processes including protein folding, endosome/lysosome function, immunity, synapse function, metal ion binding, calcium regulation and cytoskeletal function. Conclusion These studies shed light on the complex molecular events that occur during prion disease, and identify genes whose further study may yield new insights into strain specific neuropathogenesis and ante-mortem tests for TSEs.

  13. Scrapie affects the maturation cycle and immune complex trapping by follicular dendritic cells in mice.

    Science.gov (United States)

    McGovern, Gillian; Mabbott, Neil; Jeffrey, Martin

    2009-01-01

    Transmissible spongiform encephalopathies (TSEs) or prion diseases are infectious neurological disorders of man and animals, characterised by abnormal disease-associated prion protein (PrP(d)) accumulations in the brain and lymphoreticular system (LRS). Prior to neuroinvasion, TSE agents often accumulate to high levels within the LRS, apparently without affecting immune function. However, our analysis of scrapie-affected sheep shows that PrP(d) accumulations within the LRS are associated with morphological changes to follicular dendritic cells (FDCs) and tingible body macrophages (TBMs). Here we examined FDCs and TBMs in the mesenteric lymph nodes (MLNs) of scrapie-affected mice by light and electron microscopy. In MLNs from uninfected mice, FDCs could be morphologically categorised into immature, mature and regressing forms. However, in scrapie-affected MLNs this maturation cycle was adversely affected. FDCs characteristically trap and retain immune complexes on their surfaces, which they display to B-lymphocytes. In scrapie-affected MLNs, some FDCs were found where areas of normal and abnormal immune complex retention occurred side by side. The latter co-localised with PrP(d) plasmalemmal accumulations. Our data suggest this previously unrecognised morphology represents the initial stage of an abnormal FDC maturation cycle. Alterations to the FDCs included PrP(d) accumulation, abnormal cell membrane ubiquitin and excess immunoglobulin accumulation. Regressing FDCs, in contrast, appeared to lose their membrane-attached PrP(d). Together, these data suggest that TSE infection adversely affects the maturation and regression cycle of FDCs, and that PrP(d) accumulation is causally linked to the abnormal pathology observed. We therefore support the hypothesis that TSEs cause an abnormality in immune function. PMID:19997557

  14. Scrapie affects the maturation cycle and immune complex trapping by follicular dendritic cells in mice.

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    Gillian McGovern

    Full Text Available Transmissible spongiform encephalopathies (TSEs or prion diseases are infectious neurological disorders of man and animals, characterised by abnormal disease-associated prion protein (PrP(d accumulations in the brain and lymphoreticular system (LRS. Prior to neuroinvasion, TSE agents often accumulate to high levels within the LRS, apparently without affecting immune function. However, our analysis of scrapie-affected sheep shows that PrP(d accumulations within the LRS are associated with morphological changes to follicular dendritic cells (FDCs and tingible body macrophages (TBMs. Here we examined FDCs and TBMs in the mesenteric lymph nodes (MLNs of scrapie-affected mice by light and electron microscopy. In MLNs from uninfected mice, FDCs could be morphologically categorised into immature, mature and regressing forms. However, in scrapie-affected MLNs this maturation cycle was adversely affected. FDCs characteristically trap and retain immune complexes on their surfaces, which they display to B-lymphocytes. In scrapie-affected MLNs, some FDCs were found where areas of normal and abnormal immune complex retention occurred side by side. The latter co-localised with PrP(d plasmalemmal accumulations. Our data suggest this previously unrecognised morphology represents the initial stage of an abnormal FDC maturation cycle. Alterations to the FDCs included PrP(d accumulation, abnormal cell membrane ubiquitin and excess immunoglobulin accumulation. Regressing FDCs, in contrast, appeared to lose their membrane-attached PrP(d. Together, these data suggest that TSE infection adversely affects the maturation and regression cycle of FDCs, and that PrP(d accumulation is causally linked to the abnormal pathology observed. We therefore support the hypothesis that TSEs cause an abnormality in immune function.

  15. Scrapie infectivity is quickly cleared in tissues of orally-infected farmed fish

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    Faoro Franco

    2006-06-01

    Full Text Available Abstract Background Scrapie and bovine spongiform encephalopathy (BSE belongs to the group of animal transmissible spongiform encephalopathy (TSE. BSE epidemic in the UK and elsewhere in Europe has been linked to the use of bovine meat and bone meals (MBM in the feeding of cattle. There is concern that pigs, poultry and fish bred for human consumption and fed with infected MBM would eventually develop BSE or carry residual infectivity without disease. Although there has been no evidence of infection in these species, experimental data on the susceptibility to the BSE agent of farm animals other than sheep and cow are limited only to pigs and domestic chicken. In the framework of a EU-granted project we have challenged two species of fish largely used in human food consumption, rainbow trout (Oncorhynchus mykiss and turbot (Scophthalmus maximus, with a mouse-adapted TSE strain (scrapie 139A, to assess the risk related to oral consumption of TSE contaminated food. In trout, we also checked the "in vitro" ability of the pathological isoform of the mouse prion protein (PrPSc to cross the intestinal epithelium when added to the mucosal side of everted intestine. Results Fish challenged with a large amount of scrapie mouse brain homogenate by either oral or parenteral routes, showed the ability to clear the majority of infectivity load. None of the fish tissues taken at different time points after oral or parenteral inoculation was able to provoke scrapie disease after intracerebral inoculation in recipient mice. However, a few recipient mice were positive for PrPSc and spongiform lesions in the brain. We also showed a specific binding of PrPSc to the mucosal side of fish intestine in the absence of an active uptake of the prion protein through the intestinal wall. Conclusion These results indicate that scrapie 139A, and possibly BSE, is quickly removed from fish tissues despite evidence of a prion like protein in fish and of a specific binding of Pr

  16. Close Vicinity of PrP Expressing Cells (FDC) with Noradrenergic Fibers in Healthy Sheep Spleen

    OpenAIRE

    Bencsik, A.; Lezmi, S.; Hunsmann, G; Baron, T.

    2001-01-01

    In naturally and experimentally occurring scrapie in sheep, prions invade the immune system and replicate in lymphoid organs. Here we analysed immunohistochemically, in seven spleens of 6-month-old healthy sheep, the nature of the cells expressing prion protein (PrP) potentially supporting prion replication, as well as their relationship with autonomic innervation. PrP was identified using either RB1 rabbit antiserum or 4F2 monoclonal antibody directed against AA 108–123 portion of the bovine...

  17. Surveillance and simulation of bovine spongiform encephalopathy and scrapie in small ruminants in Switzerland

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    Zurbriggen Andreas

    2010-04-01

    Full Text Available Abstract Background After bovine spongiform encephalopathy (BSE emerged in European cattle livestock in 1986 a fundamental question was whether the agent established also in the small ruminants' population. In Switzerland transmissible spongiform encephalopathies (TSEs in small ruminants have been monitored since 1990. While in the most recent TSE cases a BSE infection could be excluded, for historical cases techniques to discriminate scrapie from BSE had not been available at the time of diagnosis and thus their status remained unclear. We herein applied state-of-the-art techniques to retrospectively classify these animals and to re-analyze the affected flocks for secondary cases. These results were the basis for models, simulating the course of TSEs over a period of 70 years. The aim was to come to a statistically based overall assessment of the TSE situation in the domestic small ruminant population in Switzerland. Results In sum 16 TSE cases were identified in small ruminants in Switzerland since 1981, of which eight were atypical and six were classical scrapie. In two animals retrospective analysis did not allow any further classification due to the lack of appropriate tissue samples. We found no evidence for an infection with the BSE agent in the cases under investigation. In none of the affected flocks, secondary cases were identified. A Bayesian prevalence calculation resulted in most likely estimates of one case of BSE, five cases of classical scrapie and 21 cases of atypical scrapie per 100'000 small ruminants. According to our models none of the TSEs is considered to cause a broader epidemic in Switzerland. In a closed population, they are rather expected to fade out in the next decades or, in case of a sporadic origin, may remain at a very low level. Conclusions In summary, these data indicate that despite a significant epidemic of BSE in cattle, there is no evidence that BSE established in the small ruminant population in

  18. On the question of proportionality of the count of observed Scrapie cases and the size of holding

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    Del Rio Vilas Victor J

    2009-05-01

    Full Text Available Abstract Background The present paper investigates the question of a suitable basic model for the number of scrapie cases in a holding and applications of this knowledge to the estimation of scrapie-affected holding population sizes and adequacy of control measures within holding. Is the number of scrapie cases proportional to the size of the holding in which case it should be incorporated into the parameter of the error distribution for the scrapie counts? Or, is there a different – potentially more complex – relationship between case count and holding size in which case the information about the size of the holding should be better incorporated as a covariate in the modeling? Methods We show that this question can be appropriately addressed via a simple zero-truncated Poisson model in which the hypothesis of proportionality enters as a special offset-model. Model comparisons can be achieved by means of likelihood ratio testing. The procedure is illustrated by means of surveillance data on classical scrapie in Great Britain. Furthermore, the model with the best fit is used to estimate the size of the scrapie-affected holding population in Great Britain by means of two capture-recapture estimators: the Poisson estimator and the generalized Zelterman estimator. Results No evidence could be found for the hypothesis of proportionality. In fact, there is some evidence that this relationship follows a curved line which increases for small holdings up to a maximum after which it declines again. Furthermore, it is pointed out how crucial the correct model choice is when applied to capture-recapture estimation on the basis of zero-truncated Poisson models as well as on the basis of the generalized Zelterman estimator. Estimators based on the proportionality model return very different and unreasonable estimates for the population sizes. Conclusion Our results stress the importance of an adequate modelling approach to the association between holding

  19. Accumulation of pathological prion protein PrPSc in the skin of animals with experimental and natural scrapie.

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    Achim Thomzig

    2007-05-01

    Full Text Available Prion infectivity and its molecular marker, the pathological prion protein PrP(Sc, accumulate in the central nervous system and often also in lymphoid tissue of animals or humans affected by transmissible spongiform encephalopathies. Recently, PrP(Sc was found in tissues previously considered not to be invaded by prions (e.g., skeletal muscles. Here, we address the question of whether prions target the skin and show widespread PrP(Sc deposition in this organ in hamsters perorally or parenterally challenged with scrapie. In hamsters fed with scrapie, PrP(Sc was detected before the onset of symptoms, but the bulk of skin-associated PrP(Sc accumulated in the clinical phase. PrP(Sc was localized in nerve fibres within the skin but not in keratinocytes, and the deposition of PrP(Sc in skin showed no dependence from the route of infection and lymphotropic dissemination. The data indicated a neurally mediated centrifugal spread of prions to the skin. Furthermore, in a follow-up study, we examined sheep naturally infected with scrapie and detected PrP(Sc by Western blotting in skin samples from two out of five animals. Our findings point to the skin as a potential reservoir of prions, which should be further investigated in relation to disease transmission.

  20. Enzymatic formulation capable of degrading scrapie prion under mild digestion conditions.

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    Emeka A Okoroma

    Full Text Available The prion agent is notoriously resistant to common proteases and conventional sterilisation procedures. The current methods known to destroy prion infectivity such as incineration, alkaline and thermal hydrolysis are harsh, destructive, environmentally polluting and potentially hazardous, thus limit their applications for decontamination of delicate medical and laboratory devices, remediation of prion contaminated environment and for processing animal by-products including specified risk materials and carcases. Therefore, an environmentally friendly, non-destructive enzymatic degradation approach is highly desirable. A feather-degrading Bacillus licheniformis N22 keratinase has been isolated which degraded scrapie prion to undetectable level of PrP(Sc signals as determined by Western Blot analysis. Prion infectivity was verified by ex vivo cell-based assay. An enzymatic formulation combining N22 keratinase and biosurfactant derived from Pseudomonas aeruginosa degraded PrP(Sc at 65 °C in 10 min to undetectable level -. A time-course degradation analysis carried out at 50 °C over 2 h revealed the progressive attenuation of PrP(Sc intensity. Test of residual infectivity by standard cell culture assay confirmed that the enzymatic formulation reduced PrP(Sc infectivity to undetectable levels as compared to cells challenged with untreated standard scrapie sheep prion (SSBP/1 (p-value = 0.008 at 95% confidence interval. This novel enzymatic formulation has significant potential application for prion decontamination in various environmentally friendly systems under mild treatment conditions.

  1. Ovine progressive pneumonia provirus levels are unaffected by the prion 171R allele in an Idaho sheep flock

    Science.gov (United States)

    Selective breeding of sheep for arginine (R) at prion gene (PRNP) codon 171 confers resistance to Scrapie. The 171R allele naturally occurs at low frequency, possibly because it imparts a deleterious trait such as impaired disease resistance. Ovine Progressive Pneumonia/Maedi-Visna virus (OPPV) is...

  2. Explaining the heterogeneous scrapie surveillance figures across Europe: a meta-regression approach

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    Ru Giuseppe

    2007-06-01

    Full Text Available Abstract Background Two annual surveys, the abattoir and the fallen stock, monitor the presence of scrapie across Europe. A simple comparison between the prevalence estimates in different countries reveals that, in 2003, the abattoir survey appears to detect more scrapie in some countries. This is contrary to evidence suggesting the greater ability of the fallen stock survey to detect the disease. We applied meta-analysis techniques to study this apparent heterogeneity in the behaviour of the surveys across Europe. Furthermore, we conducted a meta-regression analysis to assess the effect of country-specific characteristics on the variability. We have chosen the odds ratios between the two surveys to inform the underlying relationship between them and to allow comparisons between the countries under the meta-regression framework. Baseline risks, those of the slaughtered populations across Europe, and country-specific covariates, available from the European Commission Report, were inputted in the model to explain the heterogeneity. Results Our results show the presence of significant heterogeneity in the odds ratios between countries and no reduction in the variability after adjustment for the different risks in the baseline populations. Three countries contributed the most to the overall heterogeneity: Germany, Ireland and The Netherlands. The inclusion of country-specific covariates did not, in general, reduce the variability except for one variable: the proportion of the total adult sheep population sampled as fallen stock by each country. A large residual heterogeneity remained in the model indicating the presence of substantial effect variability between countries. Conclusion The meta-analysis approach was useful to assess the level of heterogeneity in the implementation of the surveys and to explore the reasons for the variation between countries.

  3. Paradox of Genetic Diversity in the Case of Prionic Diseases in Sheep Breeds from Romania

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    Gheorghe Hrinca

    2016-05-01

    Full Text Available The main target of this debate is the revaluation of the biodiversity concept and especially of its significance in the animal husbandry field. The paper analyzes the genetic diversity at the determinant locus of scrapie (PrP in the sheep breeds from Romania: Palas Merino, Tsigai, Tsurcana, Botosani Karakul, Palas Meat Breed and Palas Milk Breed. The prionic genetic diversity (d has been quantified by means of informational energy (e. This study highlights the impact of increasing the genetic diversity from the PrP locus level on the health status of ovine species and especially on human food safety. The informational statistics processing shows that the resistance / susceptibility to scrapie is in relation to the degree of prionic genetic diversity. The limitation of genetic diversity by selecting the individuals possessing the ARR allele in both homozygous status and in combination with alleles ARQ, ARH AHQ confers to sheep herds certain levels of resistance to contamination with scrapie disease. Instead, promoting to reproduction also individuals possessing the VRQ allele in all possible genotypic combinations (including ARR allele increases genetic diversity but also has as effect increasing the susceptibility of sheep to prion disease onset. From the point of view of morbid phenomenon, the Botosani Karakul breed is clearly advantaged compared to all other indigenous sheep breeds from Romania. For methodological coherency in the interpretative context of this issue, the genetic diversity was analyzed in association with the heterozygosity degree of breeds and their Hardy-Weinberg genetic equilibrium at the PrP locus level. Finally, the paper refers to decisions that the improvers must take to achieve the genetic prophylaxis in the scrapie case taking into account the polymorphism degree of prion protein.

  4. Transcriptomic determinants of scrapie prion propagation in cultured ovine microglia

    Science.gov (United States)

    While infection by scrapie prions is dependent on expression of cellular prion protein (PrP-C), other factors must play a role since not all cells that express equivalent levels of PrP-C are permissive to infection. The aim of this study was to determine the cellular factors associated with permissi...

  5. Prion protein gene frequencies in three Sicilian dairy sheep populations

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    Santo Caracappa

    2010-01-01

    Full Text Available The objective of this paper was to investigate the prion protein (PrP genotype and haplotype frequencies in three Sicilian dairy sheep populations. The three populations were: (1 1096 Valle del Belice animals, (2 1143 Comisana animals, and (3 1771 individuals from 5 flocks with scrapie outbreaks, in which the animals were crossbreds derived from indigenous Sicilian dairy breeds. PrP genotypes are described for the three codons 136 (Alanine or Valine; A, V, 154 (Histidine or Arginine; H, R, and 171 (Glutamine, Arginine or Histidine; Q, R, H which represent polymorphisms known to be linked with scrapie susceptibility. The Valle del Belice haplotype frequencies were 32.3% ARR, 6.5% AHQ, 1.0% ARH, 58.8% ARQ, and 1.4% VRQ. The Comisana frequencies were 39.4% ARR, 2.9% AHQ, 2.9% ARH, 50.9% ARQ, and 3.9% VRQ. In the flocks with scrapie outbreaks the frequencies were 32.8% ARR, 2.4% AHQ, 1.7% ARH, 59.1% ARQ, and 3.9% VRQ. In all three populations ARQ and ARR were the most frequent haplotypes. Multiple generations of strong selection will be needed to fixate the most resistant ARR haplotype.

  6. Genetic resistance to infections in sheep.

    Science.gov (United States)

    Bishop, S C

    2015-12-14

    This paper considers genetic resistance to infectious disease in sheep, with appropriate comparison with goats, and explores how such variation may be used to assist in disease control. Many studies have attempted to quantify the extent to which host animals differ genetically in their resistance to infection or in the disease side-effects of infection, using either recorded animal pedigrees or information from genetic markers to quantify the genetic variation. Across all livestock species, whenever studies are sufficiently well powered, then genetic variation in disease resistance is usually seen and such evidence is presented here for three infections or diseases of importance to sheep, namely mastitis, foot rot and scrapie. A further class of diseases of importance in most small ruminant production systems, gastrointestinal nematode infections, is outside the scope of this review. Existence of genetic variation implies the opportunity, at least in principle, to select animals for increased resistance, with such selection ideally used as part of an integrated control strategy. For each of the diseases under consideration, evidence for genetic variation is presented, the role of selection as an aid to disease control is outlined and possible side effects of selection in terms of effects in performance, effects on resistance to other diseases and potential parasite/pathogen coevolution risks are considered. In all cases, the conclusion is drawn that selection should work and it should be beneficial, with the main challenge being to define cost effective selection protocols that are attractive to sheep farmers. PMID:26260859

  7. Issues and perspectives in dairy sheep breeding

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    Pierlorenzo Secchiari

    2010-01-01

    Full Text Available The present review consists of two parts. In the first part, the authors briefly describe the state of the art of breedingprogrammes for Italian dairy sheep; then they report new models for genetic evaluation and consider the problem ofgenotype x environment interaction and the impact of farming systems on the genetic merit of animals. In the secondpart new breeding goals regarding the evolution of milk quality concept and the increasing importance of functional traitsare reported. Regarding milk quality, the authors especially focus on the traits related to cheese-making ability and onthe nutraceutical aspects of milk. Among functional traits, resistance to diseases (mastitis and Scrapie has been highlightedfor its great importance in livestock species. Finally, the perspectives of marker-assisted selection have also beenreported.

  8. Resistance of Neonatal Mice to Scrapie Is Associated with Inefficient Infection of the Immature Spleen

    OpenAIRE

    Ierna, Michelle; Farquhar, Christine F.; Outram, George W.; Bruce, Moira E.

    2006-01-01

    Previous studies demonstrated that neonatal mice up to about a week old are less susceptible than adult mice to infection by intraperitoneal inoculation with mouse-passaged scrapie. In peripherally inoculated adult mice, scrapie replicates in lymphoid tissues such as the spleen before invading the central nervous system. Here, we investigated scrapie susceptibility in neonatal mice in more detail, concentrating on spleen involvement. First, we demonstrated that neonatal mice are about 10 time...

  9. In-situ spectroscopic investigation of transmissible spongiform encephalopathies: application of Fourier-transform infrared spectroscopy to a scrapie-hamster model

    Science.gov (United States)

    Kneipp, Janina; Lasch, Peter; Beekes, Michael; Naumann, Dieter

    2002-03-01

    Transmissible spongiform encephalopathies (TSE), such as BSE in cattle, scrapie in sheep and goats, and Creutzfeldt-Jakob disease in man are a group of fatal infectious diseases of the central nervous system that are far from being fully understood. Presuming the pathological changes to originate from small disease-specific compositional and structural modifications at the molecular level, Fourier-transform infrared (FTIR) spectroscopy can be used to achieve insight into biochemical parameters underlying pathogenesis. We have developed an FTIR microspectroscopy-based strategy which, as a combination of image reconstruction and multivariate pattern recognition methods, permitted the comparison of identical substructures in the cerebellum of healthy and TSE-infected Syrian hamsters in the terminal stage of the disease. Here we present FTIR data about the pathological changes of scrapie-infected and normal tissue of the gray matter structures stratum granulosum and stratum moleculare. IR spectroscopy was also applied to tissue pieces of the medulla oblongata of infected and control Syrian hamsters. Mapping data were analyzed with cluster analysis and imaging methods. We found variations in the spectra of the infected tissue, which are due to changes in carbohydrates, nucleic acids, phospholipids, and proteins.

  10. Identification of a Protein that Purifies with the Scrapie Prion

    Science.gov (United States)

    Bolton, David C.; McKinley, Michael P.; Prusiner, Stanley B.

    1982-12-01

    Purification of prions from scrapie-infected hamster brain yielded a protein that was not found in a similar fraction from uninfected brain. The protein migrated with an apparent molecular size of 27,000 to 30,000 daltons in sodium dodecyl sulfate polyacrylamide gels. The resistance of this protein to digestion by proteinase K distinguished it from proteins of similar molecular weight found in normal hamster brain. Initial results suggest that the amount of this protein correlates with the titer of the agent.

  11. Chronic wasting disease and atypical forms of bovine spongiform encephalopathy and scrapie are not transmissible to mice expressing wild-type levels of human prion protein.

    Science.gov (United States)

    Wilson, Rona; Plinston, Chris; Hunter, Nora; Casalone, Cristina; Corona, Cristiano; Tagliavini, Fabrizio; Suardi, Silvia; Ruggerone, Margherita; Moda, Fabio; Graziano, Silvia; Sbriccoli, Marco; Cardone, Franco; Pocchiari, Maurizio; Ingrosso, Loredana; Baron, Thierry; Richt, Juergen; Andreoletti, Olivier; Simmons, Marion; Lockey, Richard; Manson, Jean C; Barron, Rona M

    2012-07-01

    The association between bovine spongiform encephalopathy (BSE) and variant Creutzfeldt-Jakob disease (vCJD) has demonstrated that cattle transmissible spongiform encephalopathies (TSEs) can pose a risk to human health and raises the possibility that other ruminant TSEs may be transmissible to humans. In recent years, several novel TSEs in sheep, cattle and deer have been described and the risk posed to humans by these agents is currently unknown. In this study, we inoculated two forms of atypical BSE (BASE and H-type BSE), a chronic wasting disease (CWD) isolate and seven isolates of atypical scrapie into gene-targeted transgenic (Tg) mice expressing the human prion protein (PrP). Upon challenge with these ruminant TSEs, gene-targeted Tg mice expressing human PrP did not show any signs of disease pathology. These data strongly suggest the presence of a substantial transmission barrier between these recently identified ruminant TSEs and humans. PMID:22495232

  12. Chronic wasting disease and atypical forms of bovine spongiform encephalopathy and scrapie are not transmissible to mice expressing wild-type levels of human prion protein.

    Science.gov (United States)

    Wilson, Rona; Plinston, Chris; Hunter, Nora; Casalone, Cristina; Corona, Cristiano; Tagliavini, Fabrizio; Suardi, Silvia; Ruggerone, Margherita; Moda, Fabio; Graziano, Silvia; Sbriccoli, Marco; Cardone, Franco; Pocchiari, Maurizio; Ingrosso, Loredana; Baron, Thierry; Richt, Juergen; Andreoletti, Olivier; Simmons, Marion; Lockey, Richard; Manson, Jean C; Barron, Rona M

    2012-07-01

    The association between bovine spongiform encephalopathy (BSE) and variant Creutzfeldt-Jakob disease (vCJD) has demonstrated that cattle transmissible spongiform encephalopathies (TSEs) can pose a risk to human health and raises the possibility that other ruminant TSEs may be transmissible to humans. In recent years, several novel TSEs in sheep, cattle and deer have been described and the risk posed to humans by these agents is currently unknown. In this study, we inoculated two forms of atypical BSE (BASE and H-type BSE), a chronic wasting disease (CWD) isolate and seven isolates of atypical scrapie into gene-targeted transgenic (Tg) mice expressing the human prion protein (PrP). Upon challenge with these ruminant TSEs, gene-targeted Tg mice expressing human PrP did not show any signs of disease pathology. These data strongly suggest the presence of a substantial transmission barrier between these recently identified ruminant TSEs and humans.

  13. Expression patterns of prion protein gene in differential genotypes sheep: quantification using molecular beacon real-time RT-PCR.

    Science.gov (United States)

    Wang, Chuan; Wu, Run; Li, Fa-Di; Liu, Lei; Zhang, Xiao-Li; Zhao, Chun-Lin; Diao, Xiao-Long; Guan, Hong-Wei

    2011-06-01

    Determination of the transcription level of cellular prion protein (PrP(C)) is essential for understanding its role in organisms and revealing mechanism of susceptibility and resistance to scrapie. However, the expression of prion protein (PrP) mRNA in sheep has not been quantified in great detail in digestive tract which is important during scrapie spread through oral route. Herein, we report on measurement of sheep PrP mRNA using absolute quantitative real-time RT-PCR. Total RNA was isolated from five different regions of the central nervous system (CNS), four regions of lymphoid system, eleven regions of digestive tract, and two reproductive organ tissues of eight sheep of two different genotypes (ARR/ARQ and ARH/ARQ) and PrP mRNA was quantified by real-time RT-PCR using molecular beacon. The results showed that highest levels of PrP mRNA were expressed in thalamus and cerebrum (P mRNA expression in sheep for further studies of pathogenesis of prion diseases.

  14. Eradication of scrapie with selective breeding: are we nearly there?

    OpenAIRE

    Davidse Aart; Bossers Alex; Hagenaars Thomas J; Windig Jack J; Melchior Marielle B; van Zijderveld Fred G

    2010-01-01

    Abstract Background Following EU decision 2003/100/EC Member States have recently implemented sheep breeding programmes to reduce the prevalence of sheep with TSE susceptible prion genotypes. The present paper investigates the progress of the breeding programme in the Netherlands. The PrP genotype frequencies were monitored through time using two sets of random samples: one set covers the years 2005 to 2008 and is taken from national surveillance programme; the other is taken from 168 random ...

  15. Changed iron regulation in scrapie-infected neuroblastoma cells.

    Science.gov (United States)

    Fernaeus, Sandra; Hälldin, Jonas; Bedecs, Katarina; Land, Tiit

    2005-02-18

    Prion diseases are characterized by the conversion of the normal cellular prion protein PrP(C) into a pathogenic isoform, PrP(Sc). The mechanisms involved in neuronal cell death in prion diseases are largely unknown, but accumulating evidence has demonstrated oxidative impairment along with metal imbalances in scrapie-infected brains. In this study, we report changes in cellular iron metabolism in scrapie-infected mouse neuroblastoma N2a cells (ScN2a). We detected twofold lower total cellular iron and calcein-chelatable cytosolic labile iron pool (LIP) in ScN2a cells as compared to the N2a cells. We also measured in ScN2a cells significantly lower activities of iron regulatory proteins 1 and 2 (IRP1 and IRP2, respectively), regulators of cellular iron by sensing cytosolic free iron levels and controlling posttranscriptionally the expression of the major iron transport protein transferrin receptor 1 (TfR1) and the iron sequestration protein ferritin. IRP1 and IRP2 protein levels were decreased by 40% and 50%, respectively, in ScN2a cells. TfR1 protein levels were fourfold reduced and ferritin levels were threefold reduced in ScN2a cells. TfR1 and ferritin mRNA levels were significantly reduced in ScN2a cells. ScN2a cells responded normally to iron and iron chelator treatment with respect to the activities of IRP1 and IRP2, and biosynthesis of TfR1 and ferritin. However, the activities of IRP1 and IRP2, and protein levels of TfR1 and ferritin, were still significantly lower in iron-depleted ScN2a cells as compared to the N2a cells, suggesting lower need for iron in ScN2a cells. Our results demonstrate that scrapie infection leads to changes in cellular iron metabolism, affecting both total cellular and cytosolic free iron, and the activities and expression of major regulators of cellular iron homeostasis. PMID:15710243

  16. Immunohistochemical detection and distribution of prion protein in a goat with natural scrapie.

    Science.gov (United States)

    Valdez, Reginald A; Rock, Matthew J; Anderson, Anne K; O'Rourke, Katherine I

    2003-03-01

    Formalin-fixed, paraffin-embedded tissue sections from a 3-year-old female Angora goat suffering from clinical scrapie were immunostained after hydrated autoclaving using a monoclonal antibody (mAb, F99/97.6.1; IgG1) specific for a conserved epitope on the prion protein. Widespread and prominent deposition of the scrapie isoform of the prion protein (PrPSc) was observed in the brain, brainstem, spinal cord, retina, postganglionic neurons associated with parasympathetic ganglia of myenteric and submucosal plexuses, Peyer's patches, peripheral lymph nodes, and pharyngeal and palatine tonsils. The goat was homozygous for PrP alleles encoding 5 octapeptide repeat sequences in the N-terminal region of the prion protein and isoleucine at codon 142, a genotype associated with high susceptibility and short incubation times in goats. The results of this study indicate that mAb F99/97.6.1 is useful for detection of PrPSc deposition, and this is a specific and reliable immunohistochemical adjunct to histopathology for diagnosis of natural caprine scrapie, although precise determination of the diagnostic sensitivity and specificity of the assay as a diagnostic test for scrapie in goats will require examination of a sufficiently large sample size. As with ovine scrapie, prion protein is widely distributed in the central and peripheral nervous systems, gastrointestinal tract, and lymphoid tissues in natural caprine scrapie. PMID:12661726

  17. Cloning of a Gene Whose Expression is Increased in Scrapie and in Senile Plaques in Human Brain

    Science.gov (United States)

    Wietgrefe, S.; Zupancic, M.; Haase, A.; Chesebro, B.; Race, R.; Frey, W.; Rustan, T.; Friedman, R. L.

    1985-12-01

    A complementary DNA library was constructed from messenger RNA's extracted from the brains of mice infected with the scrapie agent. The library was differentially screened with the objectives of finding clones that might be used as markers of infection and finding clones of genes whose increased expression might be correlated with the pathological changes common to scrapie and Alzheimer's disease. A gene was identified whose expression is increased in scrapie. The complementary DNA corresponding to this gene hybridized preferentially and focally to cells in the brains of scrapie-infected animals. The cloned DNA also hybridized to the neuritic plaques found with increased frequency in brains of patients with Alzheimer's disease.

  18. Scrapie pathogenesis: the role of complement C1q in scrapie agent uptake by conventional dendritic cells.

    Science.gov (United States)

    Flores-Langarica, Adriana; Sebti, Yasmine; Mitchell, Daniel A; Sim, Robert B; MacPherson, Gordon G

    2009-02-01

    Mice lacking complement components show delayed development of prion disease following peripheral inoculation. The delay could relate to reduced scrapie prion protein (PrP(Sc)) accumulation on follicular dendritic cells (DCs). However conventional DCs (cDCs) play a crucial role in the early pathogenesis of prion diseases and complement deficiency could result in decreased PrP(Sc) uptake by cDCs in the periphery. To explore this possibility, we cultured murine splenic or gut-associated lymph node cDCs with scrapie-infected whole brain homogenate in the presence or absence of complement. Uptake decreased significantly if the serum in the cultures was heat-inactivated. Because heat inactivation primarily denatures C1q, we used serum from C1q(-/-) mice and showed that PrP(Sc) uptake was markedly decreased. PrP(Sc) internalization was saturable and temperature-dependent, suggesting receptor-mediated uptake. Furthermore, uptake characteristics differed from fluid-phase endocytosis. Immunofluorescence showed colocalization of C1q and PrP(Sc), suggesting interaction between these molecules. We evaluated the expression of several complement receptors on cDCs and confirmed that cDCs that take up PrP(Sc) express one of the C1q receptors, calreticulin. Our results show that C1q participates in PrP(Sc) uptake by cDCs, revealing a critical role for cDCs in initial prion capture, an event that takes place before the PrP(Sc) accumulation within the follicular DC network. PMID:19155476

  19. Selection of ovine housekeeping genes for normalisation by real-time RT-PCR; analysis of PrP gene expression and genetic susceptibility to scrapie

    Directory of Open Access Journals (Sweden)

    Hurtado Ana

    2005-09-01

    Full Text Available Abstract Background Cellular prion protein expression is essential for the development of transmissible spongiform encephalopathies (TSEs, and in sheep, genetic susceptibility to scrapie has been associated to PrP gene polymorphisms. To test the hypothetical linkage between PrP gene expression and genetic susceptibility, PrP mRNA levels were measured by real-time RT-PCR in six ovine tissues of animals with different genotypes. Results Previous to the PrP gene expression analysis the stability of several housekeeping (HK genes was assessed in order to select the best ones for relative quantification. The normalisation of gene expression was carried out using a minimum of three HK genes in order to detect small expression differences more accurately than using a single control gene. The expression stability analysis of six HK genes showed a large tissue-associated variation reflecting the existence of tissue-specific factors. Thereby, a specific set of HK genes was required for an accurate normalisation of the PrP gene expression within each tissue. Statistical differences in the normalised PrP mRNA levels were found among the tissues, obtaining the highest expression level in obex, followed by ileum, lymph node, spleen, cerebellum and cerebrum. A tendency towards increased PrP mRNA levels and genetic susceptibility was observed in central nervous system. However, the results did not support the hypothesis that PrP mRNA levels vary between genotypes. Conclusion The results on PrP gene expression presented here provide valuable baseline data for future studies on scrapie pathogenesis. On the other hand, the results on stability data of several HK genes reported in this study could prove very useful in other gene expression studies carried out in these relevant ovine tissues.

  20. Detection of water-soluble disease-associated PrP species in blood and brain of scrapie-infected hamster.

    Science.gov (United States)

    Abdel-Haq, Hanin

    2015-09-01

    The high-speed supernatant (S(HS)) of scrapie-infected hamster brain homogenate contains a soluble infectivity similar to that of the plasma that escapes leukodepletion and can transmit prion infection. This recent finding highlights the fact that soluble prion infectivity could be relevant for prion disease propagation and progression. PrP(Sc) is essential in prion disease pathogenesis, but little to nothing is known about the PrP(Sc) species that may be associated with this form of prion infectivity. Scrapie-infected hamster plasma and S(HS) were subjected to biochemical analysis, and the results demonstrate for the first time that soluble infectivity is associated with a water-soluble PrP(Sc) species with substantially different properties from classical PrP(Sc), the concentration of which seems to correlate with the magnitude and efficiency of the soluble infectivity. Such characteristics suggest that this species might represent the soluble prion agent itself or its vehicle, highlighting the need to adequately revise the strategies involved in prion removal, diagnosis, and therapy. PMID:26105967

  1. Evaluation of an Inhouse Rapid ELISA Test for Detection of Giardia in Domestic Sheep (Ovis aries)

    OpenAIRE

    Wilson, Jolaine M; Hankenson, F Claire

    2010-01-01

    Sheep (Ovis aries) are increasingly used at our institution as models of human disease. Within the research environment, routine husbandry and handling of sheep has potential for transmission of zoonotic agents, including Giardia. The prevalence of Giardia in sheep may approach 68%. Classic diagnostic testing involves microscopic examination for fecal cysts or trophozoites; however, limitations of microscopy include time, labor, and potential false-negative results due to intermittent sheddin...

  2. Parturition difficulties in sheep

    NARCIS (Netherlands)

    Grommers, F. J.; Elving, L.; Eldik, P. van

    1985-01-01

    The incidence of difficult parturition was recorded in Texel Sheep lambs (224), Milk Sheep lambs (273) and various crossbreeds (1043) in ten spring lambing seasons. at lambing time the ewes were under 24-hour observation. Difficult parturition is defined as necessity for obstetrical assistance as a

  3. Classical antiparticles

    Energy Technology Data Exchange (ETDEWEB)

    Costella, J.P.; McKellar, B.H.J.; Rawlinson, A.A.

    1997-03-01

    We review how antiparticles may be introduced in classical relativistic mechanics, and emphasize that many of their paradoxical properties can be more transparently understood in the classical than in the quantum domain. (authors). 13 refs., 1 tab.

  4. Unusual resistance to ionizing radiation of the viruses of kuru, Creutzfeldt-Jakob disease, and scrapie.

    Science.gov (United States)

    Gibbs, C J; Gajdusek, D C; Latarjet, R

    1978-01-01

    The titers of several preparations of kuru. Creutzfeldt-Jacob disease, and scrapie viruses were reduced by only 1/10th or less by high doses of gamma radiation of 50 kGy and by only 1/10th-1/1000th or less for 200 kGy. This unusual radiation resistance of the two human viruses further links them with the scrapie virus and suggests that the genetic information of all three viruses is considerably smaller than that of any other known viruses of mammals. PMID:104301

  5. Oral scrapie infection modifies the homeostasis of Peyer's patches' dendritic cells.

    Science.gov (United States)

    Dorban, Gauthier; Defaweux, Valérie; Levavasseur, Etienne; Demonceau, Caroline; Thellin, Olivier; Flandroy, Sylvain; Piret, Joëlle; Falisse, Nandini; Heinen, Ernst; Antoine, Nadine

    2007-09-01

    In transmitted prion diseases the immune system supports the replication and the propagation of the pathogenic agent (PrPSc). DCs, which are mobile cells present in large numbers within lymph organs, are suspected to carry prions through the lymphoid system and to transfer them towards the peripheral nervous system. In this study, C57Bl/6 mice were orally inoculated with PrPSc (scrapie strain 139A) and sacrificed at the preclinical stages of the disease. Immunolabelled cryosections of Peyer's patches were analysed by confocal microscopy. Membrane prion protein expression was studied by flow cytometry. In Peyer's patches (PP), dissected at day one and day 105 after oral exposure to scrapie, we observed an increased population of DCs localised in the follicular-associated epithelium. On day 105, PrPSc was found in the follicles inside the PP of prion-infected mice. A subset of Peyer's patches DCs, which did not express cellular prion protein on their surface in non-infected mice conditions, was prion-positive in scrapie conditions. Within Peyer's patches oral scrapie exposure thus induced modifications of the homeostasis of DCs at the preclinical stages of the disease. These results give new arguments in favour of the implication of DCs in prion diseases. PMID:17622551

  6. 9 CFR 54.9 - Waiver of requirements for scrapie control pilot projects.

    Science.gov (United States)

    2010-01-01

    ... contains testing or other procedures that indicate that an animal, despite meeting the definition of high... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Waiver of requirements for scrapie control pilot projects. 54.9 Section 54.9 Animals and Animal Products ANIMAL AND PLANT HEALTH...

  7. 9 CFR 79.7 - Waiver of requirements for scrapie control pilot projects.

    Science.gov (United States)

    2010-01-01

    ... contains testing or other procedures that indicate that an animal, despite meeting the definition of high... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Waiver of requirements for scrapie control pilot projects. 79.7 Section 79.7 Animals and Animal Products ANIMAL AND PLANT HEALTH...

  8. Manipulation of PrPres production in scrapie-infected neuroblastoma cells

    NARCIS (Netherlands)

    Bate, C.; Langeveld, J.P.M.; Williams, A.

    2004-01-01

    In the present study the accumulation of protease resistant prion protein (PrPres) in scrapie-infected neuroblastoma cells (ScN2a cells) was shown to be dependent on culture conditions. The highest levels of PrPres were found in slow growing cells. Further increases in PrPres accumulation were obser

  9. Scrapie e seu diagnóstico diferencial em ovinos no Mato Grosso do Sul

    Directory of Open Access Journals (Sweden)

    Héllen M. Martins

    2012-12-01

    Full Text Available Scrapie é uma doença infecciosa, neurodegenerativa fatal, causada pelo príon scrapie (PrPsc. Apresenta-se tanto na forma clássica em ovinos e caprinos geneticamente susceptíveis quanto na forma atípica em ovinos. A primeira notificação oficial do Brasil à Organização Mundial de Saúde Animal (OIE, um caso da forma clássica diagnosticado no Rio Grande do Sul ocorreu em 1985, mas a doença já havia sido diagnosticada no mesmo Estado em 1978. Este trabalho objetivou descrever dois surtos de Scrapie em ovinos em Mato Grosso do Sul (MS, Brasil e investigar, por meio de imuno-histoquímica (IHQ a presença de PrPsc no Sistema Nervoso Central (SNC de ovinos examinados entre 2003 e 2010. Na primeira parte observaram-se dois ovinos com sinais clínicos típicos de scrapie, detalhando-se os sinais neurológicos, dados epidemiológicos, histopatológicos e amostras teciduais em duplicata desses ovinos foram encaminhadas para realização de diagnóstico de Raiva e para diagnóstico IHQ para príon. Na segunda parte realizou-se levantamento de laudos de necropsia e diagnósticos histopatológicos de ovinos, no período de maio de 2003 a março de 2010. Amostras de sistema nervoso central de 51 casos foram selecionados, incluindo os dois já com diagnóstico de Scrapie mencionados acima; os tecido de todos esses ovinos foram submetidos à IHQ para detecção de proteína priônica. Os 49 ovinos avaliados apresentaram resultado negativo na IHQ para príon.

  10. Classics Online.

    Science.gov (United States)

    Clayman, Dee L.

    1995-01-01

    Appraises several databases devoted to classical literature. Thesaurus Linguae Graecae (TLG) contains the entire extant corpus of ancient Greek literature, including works on lexicography and historiography, extending into the 15th century. Other works awaiting completion are the Database of Classical Bibliography and a CD-ROM pictorial dictionary…

  11. Classical integrability

    Science.gov (United States)

    Torrielli, Alessandro

    2016-08-01

    We review some essential aspects of classically integrable systems. The detailed outline of the sections consists of: 1. Introduction and motivation, with historical remarks; 2. Liouville theorem and action-angle variables, with examples (harmonic oscillator, Kepler problem); 3. Algebraic tools: Lax pairs, monodromy and transfer matrices, classical r-matrices and exchange relations, non-ultralocal Poisson brackets, with examples (non-linear Schrödinger model, principal chiral field); 4. Features of classical r-matrices: Belavin–Drinfeld theorems, analyticity properties, and lift of the classical structures to quantum groups; 5. Classical inverse scattering method to solve integrable differential equations: soliton solutions, spectral properties and the Gel’fand–Levitan–Marchenko equation, with examples (KdV equation, Sine-Gordon model). Prepared for the Durham Young Researchers Integrability School, organised by the GATIS network. This is part of a collection of lecture notes.

  12. Features of follicular dendritic cells in ovine pharyngeal tonsil: An in vivo and in vitro study in the context of scrapie pathogenesis

    OpenAIRE

    Toppets, Vinciane; Defaweux, Valérie; Piret, Joëlle; Kirschvinkc, Nathalie; Grobet, Luc; Antoine, Nadine

    2011-01-01

    Although the alimentary tract has been suggested as the most likely portal of entry in natural scrapie, a growing amount of data indicates that the respiratory system and more specifically the pharyngeal tonsils serve as a natural portal of entry for scrapie. This study describes for the first time the broad cell populations in the lymphoid compartment of pharyngeal tonsils and more specifically inside the lymphoid follicles where the scrapie agent accumulates during the period...

  13. Classical Motion

    OpenAIRE

    Mould, Richard A

    2003-01-01

    Preciously given rules allow conscious systems to be included in quantum mechanical systems. There rules are derived from the empirical experience of an observer who witnesses a quantum mechanical interaction leading to the capture of a single particle. In the present paper it is shown that purely classical changes experienced by an observer are consistent with these rules. Three different interactions are considered, two of which combine classical and quantum mechanical changes. The previous...

  14. Can SHEEP prevent wildfires?

    Science.gov (United States)

    yoder, M. R.; Turcotte, D. L.; Rundle, J. B.

    2011-12-01

    Wildfires have been shown to exhibit power law frequency-magnitude statistics with non-cumulative slope, or scaling exponent, b between approximately 1.3 slopes, smaller b values) in some regions. Ironically, aggressive wildfire suppression may be one of the most pernicious culprits. In order to study this problem, we present an agent based variation to the venerable Drossel-Schwabl forest-fire model. In addition to conventional fires, we introduce a number of simulated herbivorous endemic and environmental process (SHEEP) agents to the lattice. SHEEP fracture and trim large clusters to produce steeper frequency-size distributions of fuel clusters and model fires. We discuss the role of cluster shape, or fractal dimension, in the model, and we propose several interpretations of the SHEEP agent. Of particular interest, we discuss the effects of fire suppression as well as wildlife and livestock populations with respect to wildfire hazard.

  15. Short-term study of the uptake of PrPSc by the Peyer’s patches in hamsters after oral exposure to scrapie

    DEFF Research Database (Denmark)

    Bergström, Ann-Louise; Jensen, Tim Kåre; Heegaard, Peter M. H.;

    2006-01-01

    The disease-associated prion protein (PrPSc) has been detected in the ileal Peyer's patches of lambs as early as one week after oral exposure to scrapie. In hamsters, the earliest reported time of PrPSc detection in the Peyer's patches after oral exposure to scrapie is 69 days post...... of the scrapie agent. PrPSc was demonstrated in the Peyer's patches only a few days after exposure, i.e., much earlier than previously reported. This study Supports the view that the Peyer's patches constitute at least one of the primary entry sites of PrPSc after oral exposure to scrapie....

  16. Classical electrodynamics

    CERN Document Server

    Schwinger, Julian Seymour; Milton, K A; Tsai, W Y

    1998-01-01

    This text for the graduate classical electrodynamics course was left unfinished upon Julian Schwinger's death in 1994, but was completed by his coauthors, who have brilliantly recreated the excitement of Schwinger's novel approach. Classical Electrodynamics captures Schwinger's inimitable lecturing style, in which everything flows inexorably from what has gone before. An essential resource for both physicists and their students, the book includes a "Reader's Guide", which describes the major themes in each chapter, suggests a possible path through the book, and identifies topics for inclusion

  17. Classical Motion

    CERN Document Server

    Mould, R A

    2003-01-01

    Preciously given rules allow conscious systems to be included in quantum mechanical systems. There rules are derived from the empirical experience of an observer who witnesses a quantum mechanical interaction leading to the capture of a single particle. In the present paper it is shown that purely classical changes experienced by an observer are consistent with these rules. Three different interactions are considered, two of which combine classical and quantum mechanical changes. The previously given rules support all of these cases. Key Words: brain states, conscious observer, detector, measurement, probability current, state reduction, von Neumann, wave collapse.

  18. Impaired spleen structure and chemokine expression in ME7 scrapie-infected mice.

    Science.gov (United States)

    Kim, Soochan; Han, Sinsuk; Lee, Hyung Soo; Kim, Yong-Sun; Choi, Eun-Kyoung; Kim, Mi-Yeon

    2016-08-01

    We have previously demonstrated that prion protein-deficient (Prnp(0/0)) Zürich I mice display impaired T zone structure resulting from decreased splenic expression of the T cell homing chemokines, CCL19 and CCL21. Prions are transported to, and colonise in, the secondary lymphoid tissues. Therefore, in order to investigate how scrapie infection affects the splenic white pulp structure, we infected C57BL/6 mice with the mouse-adapted scrapie strain ME7 and analysed end-stage prion disease. We found that the white pulp regions of ME7-infected spleens were smaller, and contained markedly diminished T zones, as compared to control spleens. Although lymphoid tissue inducer cells were not affected, the expression of both CCL19 and CCL21 was decreased. In addition, the networks of follicular dendritic cells, which are known to express high levels of the cellular prion protein (PrP(C)) and to accumulate PrP(Sc) following scrapie infection, were larger in ME7-infected spleens. Further, they were associated with increased numbers of B cells expressing high levels of IgM. These data indicate that ME7-infected spleens display phenotype characteristics different from those reported for Prnp(0/0) spleens mainly due to the gain of PrP(Sc) function and suggest that the PrP(C) is required, not only to form the splenic white pulp structure, but also to maintain the intact T zone structure. PMID:27021907

  19. Salmonella in Sheep in Iceland

    Directory of Open Access Journals (Sweden)

    Gunnarsson E

    2002-03-01

    Full Text Available In 1995 several outbreaks of food poisoning in humans occurred in Iceland, that were traced to salmonella contamination of singed sheep heads. This prompted us to study the prevalence of salmonella infection in sheep and to trace where and how infection might have occurred. Faecal, intestinal contents and tonsillar samples were collected in the spring and autumn from sheep on 50 farms in the southwestern part of the country, where salmonellosis had been detected and from 5 farms in the northwestern part of the country. All faecal samples from the southwest were negative, whereas samples from 3 farms obtained in the autumn in the northwest were positive. Tonsillae taken in the autumn were positive in sheep from 3 farms in the southwest and 2 in the northwest. Our results show that salmonella infection is rare in Icelandic sheep but healthy carriers may harbour the bacteria in tonsillae. Salmonella was not detected in drainage from slaughterhouses nor in singed sheep heads.

  20. SHEEP TEMPORAL BONE

    Directory of Open Access Journals (Sweden)

    Kesavan

    2016-03-01

    Full Text Available INTRODUCTION Human temporal bones are difficult to procure now a days due to various ethical issues. Sheep temporal bone is a good alternative due to morphological similarities, easy to procure and less cost. Many middle ear exercises can be done easily and handling of instruments is done in the procedures like myringoplasty, tympanoplasty, stapedotomy, facial nerve dissection and some middle ear implants. This is useful for resident training programme.

  1. Quantitative trait loci underlying milk production traits in sheep.

    Science.gov (United States)

    Gutiérrez-Gil, B; El-Zarei, M F; Alvarez, L; Bayón, Y; de la Fuente, L F; San Primitivo, F; Arranz, J-J

    2009-08-01

    Improvement of milk production traits in dairy sheep is required to increase the competitiveness of the industry and to maintain the production of high quality cheese in regions of Mediterranean countries with less favourable conditions. Additional improvement over classical selection could be reached if genes with significant effects on the relevant traits were specifically targeted by selection. However, so far, few studies have been undertaken to detect quantitative trait loci (QTL) in dairy sheep. In this study, we present a complete genome scan performed in a commercial population of Spanish Churra sheep to identify chromosomal regions associated with phenotypic variation observed in milk production traits. Eleven half-sib families, including a total of 1213 ewes, were analysed following a daughter design. Genome-wise multi-marker regression analysis revealed a genome-wise significant QTL for milk protein percentage on chromosome 3. Eight other regions, localized on chromosomes 1, 2, 20, 23 and 25, showed suggestive significant linkage associations with some of the analysed traits. To our knowledge, this study represents the first complete genome scan for milk production traits reported in dairy sheep. The experiment described here shows that analysis of commercial dairy sheep populations has the potential to increase our understanding of the genetic determinants of complex production-related traits.

  2. Breeding Practices in Sheep Farming

    Directory of Open Access Journals (Sweden)

    M.A. Shejal

    2009-02-01

    Full Text Available The sheep is an important economic livestock species, contributing greatly to the Indian economy, especially in arid, semi arid and mountain areas. The current population in world is 1110.78 millions, around 44.85 millions (1987 sheeps in India (ICAR., 2002. Sheeps are mostly reared for meat and wool. The average annual wool production per sheep is between 3.5 to 5.5 kg of fine quality wool in Australia, New Zealand and U.S.S.R., where as in India except Magra sheep which annually yield more than 2 kg wool having staple length 5.8 cm, the average of rest of the wool produced is less than 1.0 kg per sheep of inferior quality (Banerjee G.C., 1998. Therefore many farmers in southern India adapted sheep rearing for meat production than for wool production. For yielding more production from sheep farming one should have sound knowledge of general information related to the reproduction and different breeding practices. [Vet. World 2009; 2(1.000: 43-44

  3. Classical tachyons

    International Nuclear Information System (INIS)

    A review of tachyons, with particular attention to their classical theory, is presented. The extension of Special Relativity to tachyons in two dimensional is first presented, an elegant model-theory which allows a better understanding also of ordinary physics. Then, the results are extended to the four-dimensional case (particular on tachyon mechanics) that can be derived without assuming the existence of Super-luminal reference-frames. Localizability and the unexpected apparent shape of tachyonic objects are discussed, and it is shown (on the basis of tachyon kinematics) how to solve the common causal paradoxes. In connection with General Relativity, particularly the problem of the apparent superluminal expansions in astrophysics is reviewed. The problem (still open) of the extension of relativitic theories to tachyons in four dimensions is tackled, and the electromagnetic theory of tachyons, a topic that can be relevant also for the experimental side, is reviewed. (Author)

  4. 9 CFR 54.11 - Approval of laboratories to run official scrapie tests and official genotype tests.

    Science.gov (United States)

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Approval of laboratories to run official scrapie tests and official genotype tests. 54.11 Section 54.11 Animals and Animal Products ANIMAL... hours; and (8) Will report all test results to State and Federal animal health officials within...

  5. ANTIPARASITICAL PROTECTION IN SHEEP FARMS

    Directory of Open Access Journals (Sweden)

    DOINA ARDELEANU

    2013-12-01

    Full Text Available Through our researches were carried out at ICDCOC- Palas, Constantza, we proposed ourselves to establish the poly-parasitism structure on sheep, as well as elaborating efficientical methods for anti-parasitical prophylaxis and fighting in sheep populations and pasture sourfaces, in order to ensuring anti-parasitical protection in sheep exploitations The copro-parasitological examinations was carried ovoscopicaly (flotation - by Willis and Mc. Master methods; sediment – by polyvalent method and larvoscopicaly – by Baermann method. The parasitological examination of coprological smears which were harvested on sheep showed the presence of polyparasitism phenomenon with protozoans (coccidiae: Eimeria spp. and helmints (cestodae: Moniesia expansa; gastro-intestinal nemathodes: Trichostrongylus spp., Nematodirus spp., Strongyloides papillosus and pulmonary nemathodes: Müellerius capillaris, Protostrongylus rufescens, Dictyocaulus filaria. Also, we proposed ourselves to study the paresites and their intermediary stages on pastures which were exploited with sheep, comparatively with mowed pastures. In the ansamble of research activities a special place is occupied by testing differents methods, in order to prevention and fighting of parasitical infestations on sheep and pasture in sheep farms.

  6. Eyeblink classical conditioning in the preweanling lamb.

    Science.gov (United States)

    Johnson, Timothy B; Stanton, Mark E; Goodlett, Charles R; Cudd, Timothy A

    2008-06-01

    Classical conditioning of eyeblink responses has been one of the most important models for studying the neurobiology of learning, with many comparative, ontogenetic, and clinical applications. The current study reports the development of procedures to conduct eyeblink conditioning in preweanling lambs and demonstrates successful conditioning using these procedures. These methods will permit application of eyeblink conditioning procedures in the analysis of functional correlates of cerebellar damage in a sheep model of fetal alcohol spectrum disorders, which has significant advantages over more common laboratory rodent models. Because sheep have been widely used for studies of pathogenesis and mechanisms of injury with many different prenatal or perinatal physiological insults, eyeblink conditioning can provide a well-studied method to assess postnatal behavioral outcomes, which heretofore have not typically been pursued with ovine models of developmental insults.

  7. Follicular dendritic cell dedifferentiation by treatment with an inhibitor of the lymphotoxin pathway dramatically reduces scrapie susceptibility.

    Science.gov (United States)

    Mabbott, Neil A; Young, Janice; McConnell, Irene; Bruce, Moira E

    2003-06-01

    Transmissible spongiform encephalopathies (TSEs) may be acquired peripherally, in which case infectivity usually accumulates in lymphoid tissues before dissemination to the nervous system. Studies of mouse scrapie models have shown that mature follicular dendritic cells (FDCs), expressing the host prion protein (PrP(c)), are critical for replication of infection in lymphoid tissues and subsequent neuroinvasion. Since FDCs require lymphotoxin signals from B lymphocytes to maintain their differentiated state, blockade of this stimulation with a lymphotoxin beta receptor-immunoglobulin fusion protein (LT beta R-Ig) leads to their temporary dedifferentiation. Here, a single treatment with LT beta R-Ig before intraperitoneal scrapie inoculation blocked the early accumulation of infectivity and disease-specific PrP (PrP(Sc)) within the spleen and substantially reduced disease susceptibility. These effects coincided with an absence of FDCs in the spleen for ca. 28 days after treatment. Although the period of FDC dedifferentiation was extended to at least 49 days by consecutive LT beta R-Ig treatments, this had little added protective benefit after injection with a moderate dose of scrapie. We also demonstrate that mature FDCs are critical for the transmission of scrapie from the gastrointestinal tract. Treatment with LT beta R-Ig before oral scrapie inoculation blocked PrP(Sc) accumulation in Peyer's patches and mesenteric lymph nodes and prevented neuroinvasion. However, treatment 14 days after oral inoculation did not affect survival time or susceptibility, suggesting that infectivity may have already spread to the peripheral nervous system. Although manipulation of FDCs may offer a potential approach for early intervention in peripherally acquired TSEs, these data suggest that the duration of the treatment window may vary widely depending on the route of exposure. PMID:12768004

  8. Becoming Sheep, Becoming Animal

    DEFF Research Database (Denmark)

    Grum, Charlotte; Svabo, Connie

    2016-01-01

    Proposal for Performance Research, in response to the call Turning Animal: As a part of a 2015 group exhibition exploring the history and local myths of a woman living in a Danish heath landscape 150 years ago, artist Charlotte Grum connected herself to a live sheep for 4 hours a day, 5 days a week......, for 5 weeks, turning the two into a hybrid relational assemblage, intra-acting and becoming with the heath habitat, the other by-passing human and non-human animals, the changing weather and their fluctuating biological needs. She wanted to explore the discursive and material effects of a site......-specific human-nonhuman animal intra-action, to challenge the gendered and anthropocentric reading of a particular historical subject and to explore the messy constituents of the very categories of women and animals. In general she is occupied with how to animate and perform the intra-active entanglement...

  9. Pharmacokinetics of albendazole in sheep.

    Science.gov (United States)

    Marriner, S E; Bogan, J A

    1980-07-01

    The concentrations of albendazole and its two major metabolites, the sulfoxide and sulfone, were measured in plasma and in ruminal and abomasal fluid of three sheep (surgically prepared with permanent ruminal and abomasal cannulae) orally given albendazole as a suspension at a dose rate of 10 mg/kg. Albendazole was not detectable in plasma at any time in one sheep (detection limit, 0.02 micrograms/ml) and in the other sheep, only transiently detectable. Albendazole sulfoxide was detectable in plasma and in abomasal fluid at mean peak concentrations of 3.2 and 26.2 micrograms/ml, respectively, 20 hours after administration. It is probable that much of the anthelmintic activity of albendazole in sheep is due to the metabolically formed sulfoxide and sulfone. PMID:7436109

  10. CJD and Scrapie Require Agent-Associated Nucleic Acids for Infection.

    Science.gov (United States)

    Botsios, Sotirios; Manuelidis, Laura

    2016-08-01

    Unlike Alzheimer's and most other neurodegenerative diseases, Transmissible Spongiform Encephalopathies (TSEs) are all caused by actively replicating infectious particles of viral size and density. Different strain-specific TSE agents cause CJD, kuru, scrapie and BSE, and all behave as latent viruses that evade adaptive immune responses and can persist for years in lymphoreticular tissues. A foreign viral structure with a nucleic acid genome best explains these TSE strains and their endemic and epidemic spread in susceptible species. Nevertheless, it is widely believed that host prion protein (PrP), without any genetic material, encodes all these strains. We developed rapid infectivity assays that allowed us to reproducibly isolate infectious particles where >85% of the starting titer separated from the majority of host components, including PrP. Remarkably, digestion of all forms of PrP did not reduce brain particle titers. To ask if TSE agents, as other viruses, require nucleic acids, we exposed high titer FU-CJD and 22L scrapie particles to potent nucleases. Both agent-strains were propagated in GT1 neuronal cells to avoid interference by complex degenerative brain changes that can impede nuclease digestions. After exposure to nucleases that are active in sarkosyl, infectivity of both agents was reproducibly reduced by ≥99%. No gold-stained host proteins or any form of PrP were visibly altered by these nucleases. In contrast, co-purifying protected mitochondrial DNA and circular SPHINX DNAs were destroyed. These findings demonstrate that TSE agents require protected genetic material to infect their hosts, and should reopen investigation of essential agent nucleic acids. J. Cell. Biochem. 117: 1947-1958, 2016. © 2016 Wiley Periodicals, Inc. PMID:26773845

  11. Dysfunction of mitochondrial dynamics in the brains of scrapie-infected mice

    International Nuclear Information System (INIS)

    Highlights: • Mfn1 and Fis1 are significantly increased in the hippocampal region of the ME7 prion-infected brain, whereas Dlp1 is significantly decreased in the infected brain. • Dlp1 is significantly decreased in the cytosolic fraction of the hippocampus in the infected brain. • Neuronal mitochondria in the prion-infected brains are enlarged and swollen compared to those of control brains. • There are significantly fewer mitochondria in the ME7-infected brain compared to the number in control brain. - Abstract: Mitochondrial dysfunction is a common and prominent feature of many neurodegenerative diseases, including prion diseases; it is induced by oxidative stress in scrapie-infected animal models. In previous studies, we found swelling and dysfunction of mitochondria in the brains of scrapie-infected mice compared to brains of controls, but the mechanisms underlying mitochondrial dysfunction remain unclear. To examine whether the dysregulation of mitochondrial proteins is related to the mitochondrial dysfunction associated with prion disease, we investigated the expression patterns of mitochondrial fusion and fission proteins in the brains of ME7 prion-infected mice. Immunoblot analysis revealed that Mfn1 was up-regulated in both whole brain and specific brain regions, including the cerebral cortex and hippocampus, of ME7-infected mice compared to controls. Additionally, expression levels of Fis1 and Mfn2 were elevated in the hippocampus and the striatum, respectively, of the ME7-infected brain. In contrast, Dlp1 expression was significantly reduced in the hippocampus in the ME7-infected brain, particularly in the cytosolic fraction. Finally, we observed abnormal mitochondrial enlargement and histopathological change in the hippocampus of the ME7-infected brain. These observations suggest that the mitochondrial dysfunction, which is presumably caused by the dysregulation of mitochondrial fusion and fission proteins, may contribute to the

  12. Dysfunction of mitochondrial dynamics in the brains of scrapie-infected mice

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Hong-Seok [Department of Microbiology, College of Medicine, Hallym University, 1 Okcheon-dong, Chuncheon, Gangwon-do 200-702 (Korea, Republic of); Ilsong Institute of Life Science, Hallym University, 1605-4 Gwanyang-dong, Dongan-gu, Anyang, Gyeonggi-do 431-060 (Korea, Republic of); Choi, Yeong-Gon; Shin, Hae-Young; Oh, Jae-Min [Ilsong Institute of Life Science, Hallym University, 1605-4 Gwanyang-dong, Dongan-gu, Anyang, Gyeonggi-do 431-060 (Korea, Republic of); Park, Jeong-Ho [Department of Microbiology, College of Medicine, Hallym University, 1 Okcheon-dong, Chuncheon, Gangwon-do 200-702 (Korea, Republic of); Ilsong Institute of Life Science, Hallym University, 1605-4 Gwanyang-dong, Dongan-gu, Anyang, Gyeonggi-do 431-060 (Korea, Republic of); Kim, Jae-Il [Department of Food Science and Nutrition, Pukyong National University, 599-1 Daeyeon-3-dong, Nam-gu, Busan 608-737 (Korea, Republic of); Carp, Richard I. [New York State Institute for Basic Research in Developmental Disabilities, 1050 Forest Hill Road, Staten Island, NY 10314 (United States); Choi, Eun-Kyoung, E-mail: ekchoi@hallym.ac.kr [Ilsong Institute of Life Science, Hallym University, 1605-4 Gwanyang-dong, Dongan-gu, Anyang, Gyeonggi-do 431-060 (Korea, Republic of); Kim, Yong-Sun, E-mail: yskim@hallym.ac.kr [Department of Microbiology, College of Medicine, Hallym University, 1 Okcheon-dong, Chuncheon, Gangwon-do 200-702 (Korea, Republic of); Ilsong Institute of Life Science, Hallym University, 1605-4 Gwanyang-dong, Dongan-gu, Anyang, Gyeonggi-do 431-060 (Korea, Republic of)

    2014-05-30

    Highlights: • Mfn1 and Fis1 are significantly increased in the hippocampal region of the ME7 prion-infected brain, whereas Dlp1 is significantly decreased in the infected brain. • Dlp1 is significantly decreased in the cytosolic fraction of the hippocampus in the infected brain. • Neuronal mitochondria in the prion-infected brains are enlarged and swollen compared to those of control brains. • There are significantly fewer mitochondria in the ME7-infected brain compared to the number in control brain. - Abstract: Mitochondrial dysfunction is a common and prominent feature of many neurodegenerative diseases, including prion diseases; it is induced by oxidative stress in scrapie-infected animal models. In previous studies, we found swelling and dysfunction of mitochondria in the brains of scrapie-infected mice compared to brains of controls, but the mechanisms underlying mitochondrial dysfunction remain unclear. To examine whether the dysregulation of mitochondrial proteins is related to the mitochondrial dysfunction associated with prion disease, we investigated the expression patterns of mitochondrial fusion and fission proteins in the brains of ME7 prion-infected mice. Immunoblot analysis revealed that Mfn1 was up-regulated in both whole brain and specific brain regions, including the cerebral cortex and hippocampus, of ME7-infected mice compared to controls. Additionally, expression levels of Fis1 and Mfn2 were elevated in the hippocampus and the striatum, respectively, of the ME7-infected brain. In contrast, Dlp1 expression was significantly reduced in the hippocampus in the ME7-infected brain, particularly in the cytosolic fraction. Finally, we observed abnormal mitochondrial enlargement and histopathological change in the hippocampus of the ME7-infected brain. These observations suggest that the mitochondrial dysfunction, which is presumably caused by the dysregulation of mitochondrial fusion and fission proteins, may contribute to the

  13. Genetic components of litter size variability in sheep

    Science.gov (United States)

    SanCristobal-Gaudy, Magali; Bodin, Loys; Elsen, Jean-Michel; Chevalet, Claude

    2001-01-01

    Classical selection for increasing prolificacy in sheep leads to a concomitant increase in its variability, even though the objective of the breeder is to maximise the frequency of an intermediate litter size rather than the frequency of high litter sizes. For instance, in the Lacaune sheep breed raised in semi-intensive conditions, ewes lambing twins represent the economic optimum. Data for this breed, obtained from the national recording scheme, were analysed. Variance components were estimated in an infinitesimal model involving genes controlling the mean level as well as its environmental variability. Large heritability was found for the mean prolificacy, but a high potential for increasing the percentage of twins at lambing while reducing the environmental variability of prolificacy is also suspected. Quantification of the response to such a canalising selection was achieved. PMID:11403747

  14. Genetic components of litter size variability in sheep

    Directory of Open Access Journals (Sweden)

    Chevalet Claude

    2001-05-01

    Full Text Available Abstract Classical selection for increasing prolificacy in sheep leads to a concomitant increase in its variability, even though the objective of the breeder is to maximise the frequency of an intermediate litter size rather than the frequency of high litter sizes. For instance, in the Lacaune sheep breed raised in semi-intensive conditions, ewes lambing twins represent the economic optimum. Data for this breed, obtained from the national recording scheme, were analysed. Variance components were estimated in an infinitesimal model involving genes controlling the mean level as well as its environmental variability. Large heritability was found for the mean prolificacy, but a high potential for increasing the percentage of twins at lambing while reducing the environmental variability of prolificacy is also suspected. Quantification of the response to such a canalising selection was achieved.

  15. Coat colour pattern in Garut sheep and its crossbred

    OpenAIRE

    Ismeth Inounu; D. Ambarawati; R.H. Mulyono

    2009-01-01

    Coat colour is a qualitative trait whose expression is controlled by genes and could be used as a characteristic of sheep breed and could be used as a trade mark for certain sheep breeder enterprise. The research was done to study the coat color pattern in Garut sheep and its crossbred. In this study 178 heads of sheep was used which consisted of 64 Garut sheep (GG); 24 MG sheep (50% M and 50% G); 14 HG sheep (50% St. Croix and 50% G); 20 HMG sheep and 56 MHG sheep. HMG and MHG sheep are comp...

  16. Sheep-related Culture of Guizhou

    Institute of Scientific and Technical Information of China (English)

    WuZhengguang

    2003-01-01

    Sheep and goats, major livestock in Guizhou Steppe of southwest China, are of both practical and social value for local dwellers. As sheep is pronounced similar as "auspicious" in Chinese, its image is widely applied to every aspect of local society, including religious rites, calendar calculation, arts creation and architecture. Thus a sheep-related culture has been developed and prospered.

  17. Follicular Dendritic Cell Dedifferentiation by Treatment with an Inhibitor of the Lymphotoxin Pathway Dramatically Reduces Scrapie Susceptibility

    OpenAIRE

    Mabbott, Neil; Young, J.; McConnell, I.; Bruce, Moira

    2003-01-01

    Transmissible spongiform encephalopathies (TSEs) may be acquired peripherally, in which case infectivity usually accumulates in lymphoid tissues before dissemination to the nervous system. Studies of mouse scrapie models have shown that mature follicular dendritic cells (FDCs), expressing the host prion protein (PrP(c)), are critical for replication of infection in lymphoid tissues and subsequent neuroinvasion. Since FDCs require lymphotoxin signals from B lymphocytes to maintain their differ...

  18. Temporary blockade of the tumor necrosis factor receptor signaling pathway impedes the spread of scrapie to the brain

    OpenAIRE

    Mabbott, Neil; McGovern, Gillian; Jeffrey, Martin; Bruce, Moira

    2002-01-01

    Although the transmissible spongiform encephalopathies (TSEs) are neurodegenerative diseases, their agents usually replicate and accumulate in lymphoid tissues long before infection spreads to the central nervous system (CNS). Studies of a mouse scrapie model have shown that mature follicular dendritic cells (FDCs), which express the host prion protein (PrP(c)), are critical for replication of infection in lymphoid tissues. In the absence of mature FDCs, the spread of infection to the CNS is ...

  19. Unusual cerebral vascular prion protein amyloid distribution in scrapie-infected transgenic mice expressing anchorless prion protein

    OpenAIRE

    Rangel, Alejandra; Race, Brent; Klingeborn, Mikael; Striebel, James; Chesebro, Bruce

    2013-01-01

    Background In some prion diseases, misfolded aggregated protease-resistant prion protein (PrPres) is found in brain as amyloid, which can cause cerebral amyloid angiopathy. Small diffusible precursors of PrPres amyloid might flow with brain interstitial fluid (ISF), possibly accounting for the perivascular and intravascular distribution of PrPres amyloid. We previously reported that PrPres amyloid in scrapie-infected transgenic mice appeared to delay clearance of microinjected brain ISF trace...

  20. Pathogenesis of natural goat scrapie: modulation by host PRNP genotype and effect of co-existent conditions

    OpenAIRE

    González, Lorenzo; Martin, Stuart; Hawkins, Stephen A.C.; Goldmann, Wilfred; Jeffrey, Martin; Sisó, Sílvia

    2010-01-01

    After detection of a high prevalence of scrapie in a large dairy goat herd, 72 infected animals were examined by immunohistochemistry with prion protein (PrP) antibody Bar224 to study the pathogenesis of the infection. Tissues examined included the brain and thoracic spinal cord (TSC), a wide selection of lymphoreticular system (LRS) tissues, the distal ileum and its enteric nervous system (ENS), and other organs, including the mammary gland. The whole open reading frame of the PRNP gene was ...

  1. Milk yield of some Croatian sheep breeds

    Directory of Open Access Journals (Sweden)

    Kristijan Pandek

    2005-01-01

    Full Text Available Among the most important breeds of sheep, used for the milk production in Croatia, are the sheep from Pag, Brač, Cres, Istrian and Travnik΄s sheep, different crossbreeds and, recently, East Friesian sheep. The aim of the research was to determine the genotype effect on lactation period, milk yield and protein and fat content, which are important in cheese making. The longest lactation period (213 days had East Friesian sheep, while the highest total milk production (294 kg and the highest production of milk fat (13.38 kg and proteins (11.88 kg had crossbreeds (Cres sheep x East Friesian x Awassi. However, the highest content of milk fat (8.12 and 7.81% and proteins (6.36 and 6.26% were established in Istrian and Pag sheep milk. The longest milking period (145 days and the shortest suckling period (28 days was found in Pag sheep, while the longest suckling period was found in Istra (78 days and East Friesian (74 days sheep. The least milk in suckling period (17.46 kg or 13.38% was sucked by lambs of Pag sheep, and the most by East Friesian (111.18 kg or 39.39% and Istra sheep lambs (94.3 kg or 42.95%.

  2. Classicalization of Quantum Variables

    CERN Document Server

    Koide, T

    2014-01-01

    A systematic procedure to extract classical degrees of freedom in quantum mechanics is formulated using the stochastic variational method. With this classicalization, a hybrid model constructed from quantum and classical variables (quantum-classical hybrids) is derived systematically. In this procedure, conservation laws such as energy are maintained, and Eherefest`s theorem is still satisfied with modification. The criterion for the applicability of quantum-classical hybrids is also investigated.

  3. What classicality? Decoherence and Bohr's classical concepts

    CERN Document Server

    Schlosshauer, Maximilian

    2010-01-01

    Niels Bohr famously insisted on the indispensability of what he termed "classical concepts." In the context of the decoherence program, on the other hand, it has become fashionable to talk about the "dynamical emergence of classicality" from the quantum formalism alone. Does this mean that decoherence challenges Bohr's dictum and signifies a break with the Copenhagen interpretation-for example, that classical concepts do not need to be assumed but can be derived? In this paper we'll try to shine some light down the murky waters where formalism and philosophy cohabitate. To begin, we'll clarify the notion of classicality in the decoherence description. We'll then discuss Bohr's and Heisenberg's take on the quantum-classical problem and reflect on different meanings of the terms "classicality" and "classical concepts" in the writings of Bohr and his followers. This analysis will allow us to put forward some tentative suggestions for how we may better understand the relation between decoherence-induced classical...

  4. Improving the Local Sheep in Gansu via Crossing with Introduced Sheep Breeds Dorset and Borderdale

    Institute of Scientific and Technical Information of China (English)

    Sun; Xiaoping; Liu; Jianbin; Zhang; Wanlong; Lang; Xia; Yang; Bohui; Guo; Jian; Feng; Ruilin

    2014-01-01

    In order to improve the meat performance of local sheep in Gansu Province,Dorset and Borderdale were introduced to crossbreed with local sheep which were Tan sheep,Small-tail Han sheep and Mongolia sheep. The offspring under different crossbreeding combinations were sampled randomly at the different growing stage to measure their growth traits so as to select optimize the crossbreeding mode. The results indicated that,for the same crossbreeding mode,the growth rate of progeny was in order F3> F2> F1; for the F3 progeny,the combinations Dorset- Borderdale- Small tail Han sheep and Dorset- Borderdale- Mongolia sheep gave a higher growth rate,with a body weight of 1. 57%,3. 17%,8. 23%,1. 15% higher in male and female individuals than the counterparts of Dorset and Tan sheep and Small tail Han sheep; for the F2 progeny,the combinations Dorset- Borderdale- Small tail Han sheep and Dorset- Borderdale- Mongolia sheep also gave a higher growth rate,with a body weight of 2. 15%,4. 53%,9. 21% and 2. 75% higher in male and female individuals than the counterparts of Dorset and Tan sheep and Small tail Han sheep; for the F1 progeny,the combination Borderdale and Small tail Han sheep assumed a higher growth rate,with a body weight of 3. 23%,6. 07%,7. 42% and 8. 66% higher in male and female individuals than the counterparts of Borderdale- Mongolia sheep and Tan sheep- Small tail Han sheep,respectively. Therefore,in the Small-tail Han sheep and Mongolia sheep producing regions,the F2 or F3progeny bred by using Dorset or Borderdale sheep as male parent to cross with local breeds,or the hybrid lambs of Small-tail Han sheep and Borderdale sheep as highly qualified commodity,would produce significant economic benefit. Moreover,the novel breeds obtained by crossing were the valuable genetic resource for breeding meat sheep.

  5. Prion replication in the hematopoietic compartment is not required for neuroinvasion in scrapie mouse model.

    Science.gov (United States)

    Loeuillet, Corinne; Lemaire-Vieille, Catherine; Naquet, Philippe; Cesbron-Delauw, Marie-France; Gagnon, Jean; Cesbron, Jean-Yves

    2010-01-01

    Fatal neurodegenerative prion diseases are caused by the transmissible PrP(Sc) prion agent whose initial replication after peripheral inoculation takes place in follicular dendritic cells present in germinal centers of lymphoid organs. However, prion replication also occurs in lymphoid cells. To assess the role of the hematopoietic compartment in neuroinvasion and prion replication, we generated chimeric mice, on a uniform congenic C57/BL6J background, by bone marrow replacement with hematopoietic cells expressing different levels of PrP protein. Nine different types of chimeric mice were inoculated intraperitoneally either with the lymphotropic Rocky Mountain Laboratory (RML) strain or the non lymphotropic ME-7 scrapie strain, at different doses. Here, we clearly demonstrate that overexpression of PrP by the hematopoietic system, or the lack of PrP expression by the bone marrow derived cells, does not change the incubation time period of the disease, even when the mice are infected at limiting doses. We conclude that the hematopoietic compartment is more or less permissive to prion replication, both for RML and ME-7, but does not play a role in neuroinvasion. PMID:20957200

  6. Interaction between dendritic cells and nerve fibres in lymphoid organs after oral scrapie exposure.

    Science.gov (United States)

    Dorban, Gauthier; Defaweux, Valérie; Demonceau, Caroline; Flandroy, Sylvain; Van Lerberghe, Pierre-Bernard; Falisse-Poirrier, Nandini; Piret, Joëlle; Heinen, Ernst; Antoine, Nadine

    2007-12-01

    In transmissible spongiform encephalopathies (TSEs), the infectious agent, called PrPsc, an abnormal isoform of the cellular prion protein, accumulates and replicates in lymphoid organs before affecting the nervous system. To clarify the cellular requirements for the neuroinvasion of the scrapie agent from the lymphoid organs to the central nervous system, we have studied, by confocal microscopy, the innervations within Peyer's patches, mesenteric lymph nodes and the spleen of mice in physiological conditions and after oral exposure to prion. Contacts between nerve fibres and PrPsc-associated cells, dendritic cells (DCs) and follicular dendritic cells (FDCs), were evaluated in preclinical prion-infected mice. Using a double immunolabelling strategy, we demonstrated the lack of innervation of PrPsc-accumulating cells (FDCs). Contacts between nerve fibers and PrPsc-propagating cells (DCs) were detected in T-cell zones and cell-trafficking areas. This supports, for the first time, the possible implication of dendritic cells in the prion neuroinvasion process. PMID:17823814

  7. Role of gut macrophages in mice orally contaminated with scrapie or BSE.

    Science.gov (United States)

    Maignien, Thomas; Shakweh, Monjed; Calvo, Pilar; Marcé, Dominique; Salès, Nicole; Fattal, Elias; Deslys, Jean-Philippe; Couvreur, Patrick; Lasmezas, Corinne Ida

    2005-07-25

    While there is a growing consensus on the understanding of the propagation pathways after oral infection of transmissible spongiform encephalopathy (TSE) agents and even if the central role of follicular dendritic cells is identified, little is known about the key players in the first steps of the infection and about the site of the disease development. We investigated the role of gut macrophages, which are capable of capturing aggregates of the prion protein. PLGA particles containing clodronate were designed in order to be orally administered and to target Peyer's patches for inducing gut-associated macrophages suicide in mice. Mice were subsequently infected with scrapie or BSE by the oral route. It was found that the efficacy of macrophage suppression in the Peyer's patches correlated well with an earlier appearance of PrPres in these formations and with a higher amount of PrPres at a later stage of the infection. Thus, the capture of infectious particles that have crossed the epithelial gut barrier and their elimination by macrophages seems to be a key event to restrict the amount of agent initiating the infection. PMID:15964722

  8. Prion replication in the hematopoietic compartment is not required for neuroinvasion in scrapie mouse model.

    Directory of Open Access Journals (Sweden)

    Corinne Loeuillet

    Full Text Available Fatal neurodegenerative prion diseases are caused by the transmissible PrP(Sc prion agent whose initial replication after peripheral inoculation takes place in follicular dendritic cells present in germinal centers of lymphoid organs. However, prion replication also occurs in lymphoid cells. To assess the role of the hematopoietic compartment in neuroinvasion and prion replication, we generated chimeric mice, on a uniform congenic C57/BL6J background, by bone marrow replacement with hematopoietic cells expressing different levels of PrP protein. Nine different types of chimeric mice were inoculated intraperitoneally either with the lymphotropic Rocky Mountain Laboratory (RML strain or the non lymphotropic ME-7 scrapie strain, at different doses. Here, we clearly demonstrate that overexpression of PrP by the hematopoietic system, or the lack of PrP expression by the bone marrow derived cells, does not change the incubation time period of the disease, even when the mice are infected at limiting doses. We conclude that the hematopoietic compartment is more or less permissive to prion replication, both for RML and ME-7, but does not play a role in neuroinvasion.

  9. The Levels of Genetic Differentiation of Small-Tailed Han Sheep and Tan Sheep Populations Using Structural Loci

    Institute of Scientific and Technical Information of China (English)

    LU Sheng-xia; CHANG Hong; JI De-jun; Tsunoda Kenji; REN Zhan-jun; REN Xiang-lian; SUN Wei; YANG Zhang-ping; CHANG Guo-bin

    2006-01-01

    Using the method of "random sampling in typical colonies of the central area of the habitat" and several electrophoresis techniques, the variations of 17 structural loci encoding blood proteins in 60 Small-Tailed Han sheep and 73 Tan sheep were examined and compared with those of 14 other sheep populations in China and other countries to investigate their levels of genetic differentiation. The average heterozygosities of Small-Tailed Han sheep and Tan sheep were 0.2360 and 0.2587, respectively. The average polymorphic information content values were 0.1974 and 0.2102, respectively. The average effective numbers of alleles were 1.5723 and 1.5751, respectively. The coefficients of gene differentiation in the four groups (including 4, 6, 13, and 16 sheep populations, respectively) were 0.049323, 0.059987, 0.1728, and 0.201256,respectively, indicating that the degree of gene differentiation at the structural loci was the least in Hu sheep, Tong sheep,Small-Tailed Han sheep, and Tan sheep; followed by the above-mentioned four sheep populations and two Mongolian sheep populations; and was the highest in sheep populations belonging to the Mongolian sheep group, South Asian sheep, and European sheep. The earlier researchers' conclusions that both Small-Tailed Han sheep and Tan sheep evolved from Mongolian sheep were further verified by the results of this study. Hu sheep, Tong sheep, Small-Tailed Han sheep, and Tan sheep were decreasingly affected by the bloodline of Mongolian sheep to different degrees. The relationships among sheep populations were not closely related to the geographical distances among sheep populations.

  10. A Csf1r-EGFP Transgene Provides a Novel Marker for Monocyte Subsets in Sheep.

    Science.gov (United States)

    Pridans, Clare; Davis, Gemma M; Sauter, Kristin A; Lisowski, Zofia M; Corripio-Miyar, Yolanda; Raper, Anna; Lefevre, Lucas; Young, Rachel; McCulloch, Mary E; Lillico, Simon; Milne, Elspeth; Whitelaw, Bruce; Hume, David A

    2016-09-15

    Expression of Csf1r in adults is restricted to cells of the macrophage lineage. Transgenic reporters based upon the Csf1r locus require inclusion of the highly conserved Fms-intronic regulatory element for expression. We have created Csf1r-EGFP transgenic sheep via lentiviral transgenesis of a construct containing elements of the mouse Fms-intronic regulatory element and Csf1r promoter. Committed bone marrow macrophage precursors and blood monocytes express EGFP in these animals. Sheep monocytes were divided into three populations, similar to classical, intermediate, and nonclassical monocytes in humans, based upon CD14 and CD16 expression. All expressed EGFP, with increased levels in the nonclassical subset. Because Csf1r expression coincides with the earliest commitment to the macrophage lineage, Csf1r-EGFP bone marrow provides a tool for studying the earliest events in myelopoiesis using the sheep as a model.

  11. Emerging parasitic diseases of sheep.

    Science.gov (United States)

    Taylor, M A

    2012-09-30

    There have been changes in the emergence and inability to control of a number of sheep parasitic infections over the last decade. This review focuses on the more globally important sheep parasites, whose reported changes in epidemiology, occurrence or failure to control are becoming increasingly evident. One of the main perceived driving forces is climate change, which can have profound effects on parasite epidemiology, especially for those parasitic diseases where weather has a direct effect on the development of free-living stages. The emergence of anthelmintic-resistant strains of parasitic nematodes and the increasing reliance placed on anthelmintics for their control, can exert profound changes on the epidemiology of those nematodes causing parasitic gastroenteritis. As a consequence, the effectiveness of existing control strategies presents a major threat to sheep production in many areas around the world. The incidence of the liver fluke, Fasciola hepatica, is inextricably linked to high rainfall and is particularly prevalent in high rainfall years. Over the last few decades, there have also been increasing reports of other fluke associated diseases, such as dicroceliosis and paramphistomosis, in a number of western European countries, possibly introduced through animal movements, and able to establish with changing climates. External parasite infections, such as myiasis, can cause significant economic loss and presents as a major welfare problem. The range of elevated temperatures predicted by current climate change scenarios, result in an elongated blowfly season with earlier spring emergence and a higher cumulative incidence of fly strike. Additionally, legislative decisions leading to enforced changes in pesticide usage and choices have resulted in increased reports and spread of ectoparasitic infections, particularly mite, lice and tick infestations in sheep. Factors, such as dip disposal and associated environmental concerns, and, perhaps more

  12. Quantum computing classical physics.

    Science.gov (United States)

    Meyer, David A

    2002-03-15

    In the past decade, quantum algorithms have been found which outperform the best classical solutions known for certain classical problems as well as the best classical methods known for simulation of certain quantum systems. This suggests that they may also speed up the simulation of some classical systems. I describe one class of discrete quantum algorithms which do so--quantum lattice-gas automata--and show how to implement them efficiently on standard quantum computers.

  13. Meat quality of goat and sheep sausages

    OpenAIRE

    Teixeira, A.; Pereira, Etelvina; Rodrigues, Sandra

    2012-01-01

    The main objective of this work was to contribute to the characterization of a new product, based on goat and sheep meat with a strategy, which gives value-added to meat from culled goats and sheep, which have a very low commercial price. Carcasses from animals weighing more than the body weight allowed by PDO label specifications were used to produce fresh sausages. Sheep and goats sausages were produced in a traditional industry, in Northeast Portugal. The following character...

  14. Conservation genetics in Chinese sheep: diversity of fourteen indigenous sheep (Ovis aries) using microsatellite markers.

    Science.gov (United States)

    E, Guang-Xin; Zhong, Tao; Ma, Yue-Hui; Gao, Hui-Jiang; He, Jian-Ning; Liu, Nan; Zhao, Yong-Ju; Zhang, Jia-Hua; Huang, Yong-Fu

    2016-02-01

    The domestic sheep (Ovis aries) has been an economically and culturally important farm animal species since its domestication around the world. A wide array of sheep breeds with abundant phenotypic diversity exists including domestication and selection as well as the indigenous breeds may harbor specific features as a result of adaptation to their environment. The objective of this study was to investigate the population structure of indigenous sheep in a large geographic location of the Chinese mainland. Six microsatellites were genotyped for 611 individuals from 14 populations. The mean number of alleles (±SD) ranged from 7.00 ± 3.69 in Gangba sheep to 10.50 ± 4.23 in Tibetan sheep. The observed heterozygote frequency (±SD) within a population ranged from 0.58 ± 0.03 in Gangba sheep to 0.71 ± 0.03 in Zazakh sheep and Minxian black fur sheep. In addition, there was a low pairwise difference among the Minxian black fur sheep, Mongolian sheep, Gansu alpine merino, and Lanzhou fat-tailed sheep. Bayesian analysis with the program STRUCTURE showed support for 3 clusters, revealing a vague genetic clustering pattern with geographic location. The results of the current study inferred high genetic diversity within these native sheep in the Chinese mainland. PMID:26865968

  15. Mineral requirements of dairy sheep

    Directory of Open Access Journals (Sweden)

    Giuseppina Camboni

    2010-01-01

    Full Text Available This paper reviews the major (Calcium, Phosphorus, Potassium, Sodium, Chlorine, Sulphur, Magnesium and the trace  elements (Iron, Copper, Cobalt, Iodine, Manganese, Zync, Molybdenum, Selenium that play an essential role in animal  metabolism. For each one the authors indicate not only the function, but also the more recent advances in terms of  daily requirements for dairy sheep

  16. Feeding cassava foliage to sheep

    OpenAIRE

    Hue, Khuc Thi

    2012-01-01

    The potential of cassava foliage (Manihot esculenta Crantz) as a protein-rich feed in sheep production in Vietnam was examined by studying cassava foliage yield, hydrogen cyanide (HCN) content, toxicity and performance of lambs fed the foliage as a supplement. Cassava foliage fed ad libitum as a protein supplement to a basal diet of urea-treated rice straw gave similar lamb live weight gain (LWG) as diets supplemented with commercial concentrate or protein-rich foliage of stylosanthes (S...

  17. Strain specific resistance to murine scrapie associated with a naturally occurring human prion protein polymorphism at residue 171.

    Directory of Open Access Journals (Sweden)

    James F Striebel

    2011-09-01

    Full Text Available Transmissible spongiform encephalopathies (TSE or prion diseases are neurodegenerative disorders associated with conversion of normal host prion protein (PrP to a misfolded, protease-resistant form (PrPres. Genetic variations of prion protein in humans and animals can alter susceptibility to both familial and infectious prion diseases. The N171S PrP polymorphism is found mainly in humans of African descent, but its low incidence has precluded study of its possible influence on prion disease. Similar to previous experiments of others, for laboratory studies we created a transgenic model expressing the mouse PrP homolog, PrP-170S, of human PrP-171S. Since PrP polymorphisms can vary in their effects on different TSE diseases, we tested these mice with four different strains of mouse-adapted scrapie. Whereas 22L and ME7 scrapie strains induced typical clinical disease, neuropathology and accumulation of PrPres in all transgenic mice at 99-128 average days post-inoculation, strains RML and 79A produced clinical disease and PrPres formation in only a small subset of mice at very late times. When mice expressing both PrP-170S and PrP-170N were inoculated with RML scrapie, dominant-negative inhibition of disease did not occur, possibly because interaction of strain RML with PrP-170S was minimal. Surprisingly, in vitro PrP conversion using protein misfolding cyclic amplification (PMCA, did not reproduce the in vivo findings, suggesting that the resistance noted in live mice might be due to factors or conditions not present in vitro. These findings suggest that in vivo conversion of PrP-170S by RML and 79A scrapie strains was slow and inefficient. PrP-170S mice may be an example of the conformational selection model where the structure of some prion strains does not favor interactions with PrP molecules expressing certain polymorphisms.

  18. Entanglement in Classical Optics

    CERN Document Server

    Ghose, Partha

    2013-01-01

    The emerging field of entanglement or nonseparability in classical optics is reviewed, and its similarities with and differences from quantum entanglement clearly pointed out through a recapitulation of Hilbert spaces in general, the special restrictions on Hilbert spaces imposed in quantum mechanics and the role of Hilbert spaces in classical polarization optics. The production of Bell-like states in classical polarization optics is discussed, and new theorems are proved to discriminate between separable and nonseparable states in classical wave optics where no discreteness is involved. The influence of the Pancharatnam phase on a classical Bell-like state is deived. Finally, to what extent classical polarization optics can be used to simulate quantum information processing tasks is also discussed. This should be of great practical importance because coherence and entanglement are robust in classical optics but not in quantum systems.

  19. Molecular characterization of cryptosporidium in brazilian sheep

    Science.gov (United States)

    Feces were collected from 125 sheep between January and December 2007, on ten farms in the State of Rio de Janeiro, Brazil, and examined for the presence of Cryptosporidium. Ninety samples were collected from lambs 2 to 6 months of age, and 35 were from sheep over 12 months of age. All samples were...

  20. Microstructure and mechanical properties of sheep horn.

    Science.gov (United States)

    Zhu, Bing; Zhang, Ming; Zhao, Jian

    2016-07-01

    The sheep horn presents outstanding mechanical properties of impact resistance and energy absorption, which suits the need of the vehicle bumper design, but the mechanism behind this phenomenon is less investigated. The microstructure and mechanical properties of the sheep horn of Small Tailed Han Sheep (Ovis aries) living in northeast China were investigated in this article. The effect of sampling position and orientation of the sheep horn sheath on mechanical properties were researched by tensile and compression tests. Meanwhile, the surface morphology and microstructure of the sheep horn were observed using scanning electron microscopy (SEM). The formation mechanism of the mechanical properties of the sheep horn was investigated by biological coupling analysis. The analytical results indicated that the outstanding mechanical properties of the sheep horn are determined by configuration, structure, surface morphology and material coupling elements. These biological coupling elements make the sheep horn possess super characteristics of crashworthiness and energy absorption through the internal coupling mechanism. We suppose that these findings would make a difference in vehicle bumper design. Microsc. Res. Tech. 79:664-674, 2016. © 2016 Wiley Periodicals, Inc.

  1. Goats, sheep, and cattle: some basics

    Science.gov (United States)

    Pasture-based finishing systems for meat goats, sheep and cattle are growing rapidly in the eastern USA. Increasing demand for pasture-raised meat and dairy products requires renewed efforts to communicate the best practical information in order to initiate mixed grazing with goats, sheep, and beef...

  2. IMPY, a potential β-amyloid imaging probe for detection of prion deposits in scrapie-infected mice

    International Nuclear Information System (INIS)

    Introduction: A potential single-photon emission computed tomography imaging agent for labeling of Aβ plaques of Alzheimer's disease, IMPY (2-(4'-dimethylaminophenyl)-6-iodo-imidazo[1,2-a]pyridine), would be effective in detection of prion amyloid deposits in transmissible spongiform encephalopathies (TSEs). Methods: In vitro autoradiographic studies were carried out with [125I]IMPY on brain sections from scrapie-infected mice and age-matched controls. Competition study was performed to evaluate the prion deposit binding specificity with nonradioactive IMPY. Results: Binding of [125I]IMPY was observed in infected brain sections, while on age-matched control brain sections, there was no or very low labeling. Prion deposit binding was confirmed by histoblots with prion protein-specific monoclonal antibody 2D6. In the presence of nonradioactive IMPY, the binding of [125I]IMPY was significantly inhibited in all regions studied. Conclusions: These findings indicate that IMPY can detect the prion deposits in vitro in scrapie-infected mice. Labeled with 123I, this ligand may be useful to quantitate prion deposit burdens in TSEs by in vivo imaging

  3. IMPY, a potential {beta}-amyloid imaging probe for detection of prion deposits in scrapie-infected mice

    Energy Technology Data Exchange (ETDEWEB)

    Song, P.-J. [INSERM, U619, F-37000 Tours (France); Universite Francois-Rabelais, F-37000 Tours (France); IFR135, F-37000 Tours (France); Bernard, Serge [IFR135, F-37000 Tours (France); INRA, UR1282, IASP, 37380 Nouzilly (France)], E-mail: bernard@tours.inra.fr; Sarradin, Pierre [INRA, UR1282, IASP, 37380 Nouzilly (France); Vergote, Jackie [INSERM, U619, F-37000 Tours (France); Universite Francois-Rabelais, F-37000 Tours (France); IFR135, F-37000 Tours (France); Barc, Celine [INRA, UR1282, IASP, 37380 Nouzilly (France); Chalon, Sylvie [INSERM, U619, F-37000 Tours (France); Universite Francois-Rabelais, F-37000 Tours (France); IFR135, F-37000 Tours (France); Kung, M.-P.; Kung, Hank F. [Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104 (United States); Department of Pharmacology, University of Pennsylvania, Philadelphia, PA 19104 (United States); Guilloteau, Denis [INSERM, U619, F-37000 Tours (France); Universite Francois-Rabelais, F-37000 Tours (France); IFR135, F-37000 Tours (France)

    2008-02-15

    Introduction: A potential single-photon emission computed tomography imaging agent for labeling of A{beta} plaques of Alzheimer's disease, IMPY (2-(4'-dimethylaminophenyl)-6-iodo-imidazo[1,2-a]pyridine), would be effective in detection of prion amyloid deposits in transmissible spongiform encephalopathies (TSEs). Methods: In vitro autoradiographic studies were carried out with [{sup 125}I]IMPY on brain sections from scrapie-infected mice and age-matched controls. Competition study was performed to evaluate the prion deposit binding specificity with nonradioactive IMPY. Results: Binding of [{sup 125}I]IMPY was observed in infected brain sections, while on age-matched control brain sections, there was no or very low labeling. Prion deposit binding was confirmed by histoblots with prion protein-specific monoclonal antibody 2D6. In the presence of nonradioactive IMPY, the binding of [{sup 125}I]IMPY was significantly inhibited in all regions studied. Conclusions: These findings indicate that IMPY can detect the prion deposits in vitro in scrapie-infected mice. Labeled with {sup 123}I, this ligand may be useful to quantitate prion deposit burdens in TSEs by in vivo imaging.

  4. Establishment of a Stable PrPSc Panel from Brain Tissues of Experimental Hamsters with Scrapie Strain 263K

    Institute of Scientific and Technical Information of China (English)

    BAO-YUN ZHANG; CHAN TIAN; JUN HAN; CHEN GAO; QI SHI; JIAN-MING CHEN; HUI-YING JIANG; WEI ZHOU; XIAO-Ping DONG

    2009-01-01

    Objective To establish a stable PrPSc panel from brain tissues of experimental hamsters infected with scrapie agent 263K for evaluating diagnostic techniques of human and animals' prion diseases. Methods Thirty brain tissue samples from hamsters intracerebrally infected with scrapie strain 263K and another 30 samples from normal hamsters were selected to prepare 10%, 1%, and 0.5% brain homogenates, which were aliquoted into stocks. PrPSc in each brain homogenate was determined by proteinase K digestions followed by Western blot assay and partially by immunohistochemistry. Stability and glycoforms of PrPSc were repeatedly detected by PrPSc-specific Western blots in half a year and 3 years later. Results PrPSc signals were observed in all 10% brain homogenates of infected hamsters. Twenty out of 30 stocks and 19 out of 30 stocks were PrPSc positive in 1% and 0.5% brain homogenatesof infected hamsters, respectively. Twenty-seven out of 30 stocks presented three positive bands in 10% brain homogenates, whereas none of 1% and 0.5% homogenates contained 3 bands. The detection of PrPSc-specific signals stored in half a year and 3 years later demonstrated that the ratio of PrPSc positive samples and glycoforms was almost unchanged. All normal hamsters' brain homogenates were PrPSc negative. Conclusion A PrPSc panel of prion disease can be established, which displays reliably stable PrPSc-specific signals and glycoforms.

  5. Entanglement in Classical Optics

    OpenAIRE

    Ghose, Partha; Mukherjee, Anirban

    2013-01-01

    The emerging field of entanglement or nonseparability in classical optics is reviewed, and its similarities with and differences from quantum entanglement clearly pointed out through a recapitulation of Hilbert spaces in general, the special restrictions on Hilbert spaces imposed in quantum mechanics and the role of Hilbert spaces in classical polarization optics. The production of Bell-like states in classical polarization optics is discussed, and new theorems are proved to discriminate betw...

  6. Bidirectional coherent classical communication

    OpenAIRE

    Harrow, Aram W.; Leung, Debbie W.

    2005-01-01

    A unitary interaction coupling two parties enables quantum or classical communication in both the forward and backward directions. Each communication capacity can be thought of as a tradeoff between the achievable rates of specific types of forward and backward communication. Our first result shows that for any bipartite unitary gate, bidirectional coherent classical communication is no more difficult than bidirectional classical communication — they have the same achievable rate regions. ...

  7. Classical, Semi-classical and Quantum Noise

    CERN Document Server

    Poor, H; Scully, Marlan

    2012-01-01

    David Middleton was a towering figure of 20th Century engineering and science and one of the founders of statistical communication theory. During the second World War, the young David Middleton, working with Van Fleck, devised the notion of the matched filter, which is the most basic method used for detecting signals in noise. Over the intervening six decades, the contributions of Middleton have become classics. This collection of essays by leading scientists, engineers and colleagues of David are in his honor and reflect the wide  influence that he has had on many fields. Also included is the introduction by Middleton to his forthcoming book, which gives a wonderful view of the field of communication, its history and his own views on the field that he developed over the past 60 years. Focusing on classical noise modeling and applications, Classical, Semi-Classical and Quantum Noise includes coverage of statistical communication theory, non-stationary noise, molecular footprints, noise suppression, Quantum e...

  8. Features of follicular dendritic cells in ovine pharyngeal tonsil: an in vivo and in vitro study in the context of scrapie pathogenesis.

    Science.gov (United States)

    Toppets, Vinciane; Defaweux, Valerie; Piret, Joelle; Kirschvink, Nathalie; Grobet, Luc; Antoine, Nadine

    2011-05-15

    Although the alimentary tract has been suggested as the most likely portal of entry in natural scrapie, a growing amount of data indicates that the respiratory system and more specifically the pharyngeal tonsils serve as a natural portal of entry for scrapie. This study describes for the first time the broad cell populations in the lymphoid compartment of pharyngeal tonsils and more specifically inside the lymphoid follicles where the scrapie agent accumulates during the period of latency. Follicular dendritic cells (FDCs), stromal cells located in the light zone of the germinal centre of lymphoid follicles, seem to be the principal causal factor in the accumulation of the infectious agent in transmissible spongiform encephalopathy (TSE) diseases. Knowing that efficient lymphoreticular prion propagation requires PrPc expression, we analysed the expression of PrPc with the mouse monoclonal antibody Pri 909 both in situ and on FDC-cluster-enriched cell suspensions. In situ, a positive staining was observed in the germinal centre of pharyngeal lymph follicles. The germinal centre labelling was due to the presence of a follicular dendritic network as revealed after immunogold staining of isolated FDC clusters. Our results suggest that the pharyngeal lymphoreticular system and more specifically PrPc expressing follicular dendritic cells could serve as a prion "reservoir" during the latency phase, thus playing a key role during the scrapie lymphoinvasion. PMID:21353313

  9. Primary transmission of chronic wasting disease versus scrapie prions from small ruminants to transgenic mice expressing ovine and cervid prion protein

    Science.gov (United States)

    Identifying transmissible spongiform encephalopathy (TSE) reservoirs that could lead to disease re-emergence is imperative to U.S. scrapie eradication efforts. Transgenic mice expressing the cervid (TgElk) or ovine (Tg338) prion protein have aided characterization of chronic wasting disease (CWD) an...

  10. Teleportation via classical entanglement

    CERN Document Server

    Rafsanjani, Seyed Mohammad Hashemi; Magaña-Loaiza, Omar S; Boyd, Robert W

    2015-01-01

    We present a classical counterpart to quantum teleportation that uses classical entanglement instead of quantum entanglement. In our implementation we take advantage of classical entanglement among three parties: orbital angular momentum (OAM), polarization, and the radial degrees of freedom of a beam of light. We demonstrate the teleportation of arbitrary OAM states, in the subspace spanned by any two OAM states, to the polarization of the same beam. Our letter presents the first classical demonstration of a commonly-perceived--quantum phenomenon that requires entanglement among more than two parties.

  11. Lectures on Classical Integrability

    CERN Document Server

    Torrielli, Alessandro

    2016-01-01

    We review some essential aspects of classically integrable systems. The detailed outline of the lectures consists of: 1. Introduction and motivation, with historical remarks; 2. Liouville theorem and action-angle variables, with examples (harmonic oscillator, Kepler problem); 3. Algebraic tools: Lax pairs, monodromy and transfer matrices, classical r-matrices and exchange relations, non-ultralocal Poisson brackets, with examples (non-linear Schroedinger model, principal chiral field); 4. Features of classical r-matrices: Belavin-Drinfeld theorems, analyticity properties, and lift of the classical structures to quantum groups; 5. Classical inverse scattering method to solve integrable differential equations: soliton solutions, spectral properties and the Gel'fand-Levitan-Marchenko equation, with examples (KdV equation, Sine-Gordon model). Prepared for the Durham Young Researchers Integrability School, organised by the GATIS network. This is part of a collection of lecture notes.

  12. Rumen protozoa in South African sheep with a summary of the worldwide distribution of sheep protozoa

    OpenAIRE

    Dirk Booyse; Burk A. Dehority

    2011-01-01

    Protozoa species were identified in rumen contents of four domestic sheep (Ovis aries) from South Africa. All animals were fed a forage diet which consisted of 50% lucerne and 50% teff hay. Ten new host records were identified, bringing the total number of species and forms observed in sheep in South Africa to 30. The occurrence and geographic distribution of ciliate protozoa in both domestic and wild sheep from around the world are summarised. It was found that 15 genera and 131 species...

  13. Limited transcriptional response of ovine microglia to prion accumulation

    Science.gov (United States)

    Sheep scrapie (Sc) is the classical transmissible spongiform encephalopathy (prion disease). The conversion of normal cellular prion protein (PrPC) to disease-associated prion protein (PrPSc) is the fundamental pathogenesis of prion diseases. Many of the molecular mechanisms contributing to prion ...

  14. Davidson and classical pragmatism

    Directory of Open Access Journals (Sweden)

    Paula Rossi

    2007-06-01

    Full Text Available In this paper I wish to trace some connections between Donald Davidson's work (1917-2003 and two major representatives of the classical pragmatist movement: Charles S. Peirce (1839-1914 and William James (1842-1910. I will start with a basic characterization of classical pragmatism; then, I shall examine certain conceptions in Peirce's and James' pragmatism, in order to establish affinities with Davidson´s thought. Finally, and bearing in mind the previous con-nections, I will reflect briefly on the relevance –often unrecognized- of classical pragmatist ideas in the context of contemporary philosophi-cal discussions.

  15. Monoclonal and polyclonal antibodies for ante- and post-mortem detection of PrPSc in sheep

    Directory of Open Access Journals (Sweden)

    Michele Dietrich Moura Costa

    2015-04-01

    Full Text Available Scrapie is a disease that affects sheep and goats and is characterized by the accumulation of an abnormal isoform (PrPSc of the cellular prion protein, PrPC, in the central nervous system (CNS and in lymphoid tissues. Detection of PrPSc in these tissues can be attempted by a variety of techniques, including immunohistochemistry (IHC and western blotting (WB, for which a wide range of monoclonal and polyclonal antibodies are commercially available. The objective of this study was to test and compare the efficacy of monoclonal antibodiesF89/160.1.5, F99/97.6.1, and P4 and polyclonal antibodies M52 and R486 in the detection of PrPSc in lymphoid and CNS tissue samples by using IHC. Positive and negative control samples of sheep brain and tonsils were provided by the Animal Health and Veterinary Laboratories Agency (AHVLA, UK. The IHC examination of CNS samples with both monoclonal and polyclonal antibodies confirmed the granular deposition of PrPSc in the neurons of the positive control tissues. However, while the monoclonal antibodies did not produce positive reactions in the negative controls, the polyclonal antibodies showed some non-specific staining. The testing of positive control tonsil samples with polyclonal and monoclonal antibodies identified positive control-specific reactions, whereas the negative control tissues were IHC-negative with all antibodies, although P4 and the polyclonal antibodies produced some background staining. In summary, although the polyclonal antibodies may be more accessible, their use is not advisable because of possible false positive reactions. The polyclonal antibody M52 was able to identify PrPC in brain and spleen samples by WB but other lymphoid tissues were negative.

  16. Paratuberculosis in sheep and goats.

    Science.gov (United States)

    Windsor, P A

    2015-12-14

    Paratuberculosis is a chronic insidious, often serious, disease of the global small ruminant industries, mainly causing losses from mortalities and reduced productivity on-farm, interference in trading and, in Australia, profound socio-economic impacts that have periodically compromised harmony of rural communities. The pathogenesis, diagnosis, impacts and disease management options for ovine and caprine paratuberculosis are reviewed, comparing current controls in the extensive management system for sheep in wool flocks in Australia with the semi-intensive system of dairy flocks/herds in Greece. Improved understanding of the immune and cellular profiles of sheep with varying paratuberculosis outcomes and the recognition of the need for prolonged vaccination and biosecurity is considered of relevance to future control strategies. Paratuberculosis in goats is also of global distribution although the prevalence, economic impact and strategic control options are less well recognized, possibly due to the relatively meagre resources available for goat industry research. Although there have been some recent advances, more work is required on developing control strategies for goats, particularly in dairy situations where there is an important need for validation of improved diagnostic assays and the recognition of the potential impacts for vaccination. For all species, a research priority remains the identification of tests that can detect latent and subclinical infections to enhance removal of future sources of infectious material from flocks/herds and the food chain, plus predict the likely outcomes of animals exposed to the organism at an early age. Improving national paratuberculosis control programs should also be a priority to manage disease risk from trade. The importance of strong leadership and communication, building trust within rural communities confused by the difficulties in managing this insidious disease, reflects the importance of change management

  17. Paratuberculosis in sheep and goats.

    Science.gov (United States)

    Windsor, P A

    2015-12-14

    Paratuberculosis is a chronic insidious, often serious, disease of the global small ruminant industries, mainly causing losses from mortalities and reduced productivity on-farm, interference in trading and, in Australia, profound socio-economic impacts that have periodically compromised harmony of rural communities. The pathogenesis, diagnosis, impacts and disease management options for ovine and caprine paratuberculosis are reviewed, comparing current controls in the extensive management system for sheep in wool flocks in Australia with the semi-intensive system of dairy flocks/herds in Greece. Improved understanding of the immune and cellular profiles of sheep with varying paratuberculosis outcomes and the recognition of the need for prolonged vaccination and biosecurity is considered of relevance to future control strategies. Paratuberculosis in goats is also of global distribution although the prevalence, economic impact and strategic control options are less well recognized, possibly due to the relatively meagre resources available for goat industry research. Although there have been some recent advances, more work is required on developing control strategies for goats, particularly in dairy situations where there is an important need for validation of improved diagnostic assays and the recognition of the potential impacts for vaccination. For all species, a research priority remains the identification of tests that can detect latent and subclinical infections to enhance removal of future sources of infectious material from flocks/herds and the food chain, plus predict the likely outcomes of animals exposed to the organism at an early age. Improving national paratuberculosis control programs should also be a priority to manage disease risk from trade. The importance of strong leadership and communication, building trust within rural communities confused by the difficulties in managing this insidious disease, reflects the importance of change management

  18. Rumen protozoa in South African sheep with a summary of the worldwide distribution of sheep protozoa

    Directory of Open Access Journals (Sweden)

    Dirk Booyse

    2011-02-01

    Full Text Available Protozoa species were identified in rumen contents of four domestic sheep (Ovis aries from South Africa. All animals were fed a forage diet which consisted of 50% lucerne and 50% teff hay. Ten new host records were identified, bringing the total number of species and forms observed in sheep in South Africa to 30. The occurrence and geographic distribution of ciliate protozoa in both domestic and wild sheep from around the world are summarised. It was found that 15 genera and 131 species occur in domestic sheep globally.

  19. On Noncommutative Classical Mechanics

    CERN Document Server

    Djemai, A E F

    2003-01-01

    In this work, I investigate the noncommutative Poisson algebra of classical observables corresponding to a proposed general Noncommutative Quantum Mechanics, \\cite{1}. I treat some classical systems with various potentials and some Physical interpretations are given concerning the presence of noncommutativity at large scales (Celeste Mechanics) directly tied to the one present at small scales (Quantum Mechanics) and its possible relation with UV/IR mixing.

  20. Davidson and classical pragmatism

    OpenAIRE

    Paula Rossi

    2007-01-01

    In this paper I wish to trace some connections between Donald Davidson's work (1917-2003) and two major representatives of the classical pragmatist movement: Charles S. Peirce (1839-1914) and William James (1842-1910). I will start with a basic characterization of classical pragmatism; then, I shall examine certain conceptions in Peirce's and James' pragmatism, in order to establish affinities with Davidson´s thought. Finally, and bearing in mind the previous con-nections, I will reflect brie...

  1. Pharmacokinetics of fenbendazole in sheep.

    Science.gov (United States)

    Marriner, S E; Bogan, J A

    1981-07-01

    Concentrations of fenbendazole and its sulfoxide, oxfendazole, and sulfone metabolites were determined in 6 sheep after oral administration of fenbendazole (10 mg/kd of body weight). Mean peak concentrations in plasma of fenbendazole, oxfendazole, and sulfone of 0.15, 0.29, and 0.17 micrograms/ml occurred 24, 30, and 36 hours after administration, respectively. Mean peak concentrations in abomasal fluid were 1.82, 0.66, and 0.07 micrograms/ml occurring at 30, 48, and 72 hours, respectively. Fenbendazole and oxfendhzole were detectable in plasma and abomasal fluids for 5 days after administration. Much of the anthelmintic activity of fenbendazole may be due to the oxfendazole metabolite. Plasma concentrations of fenbendazole were less and persisted for a shorter period after intra-abomasal administration than after oral administration.

  2. Radioiodide transfer across sheep placenta

    International Nuclear Information System (INIS)

    Unidirectional transplacental clearances of radioiodide were calculated from the net radioiodide fluxes after injection into fetal and/or maternal circulations of 33 catheterized conscious sheep. Maternofetal potential difference (PD) was also recorded. Clearance reached a steady state 20 min after bolus injection. Fetomaternal clearance was related to PD. Bidirectional clearance ratios measured in five experiments showed a significant divergence from the value for passive flux predicted from the measured PD, and in four experiments these ratios were also significantly different from unity, this result being incompatible with passive flux even if the transplacental PD is assumed to be zero. Injection of thiocyanate or iodide reduced radioiodide clearance. Fetomaternal clearance of radioiodide was halved by an increase in fetal plasma iodide concentration of approximately 0.1 mM. There appears to be an inhibitable iodide-transporting site capable of active transport in either direction

  3. Schmallenberg virus experimental infection of sheep

    DEFF Research Database (Denmark)

    Wernike, Kerstin; Hoffmann, Bernd; Bréard, Emmanuel;

    2013-01-01

    Since late 2011, a novel orthobunyavirus, named Schmallenberg virus (SBV), has been implicated in many cases of severely malformed bovine and ovine offspring in Europe. In adult cattle, SBV is known to cause a mild transient disease; clinical signs include short febrile episodes, decreased milk...... production and diarrhoea for a few days. However, the knowledge about clinical signs and pathogenesis in adult sheep is limited.In the present study, adult sheep of European domestic breeds were inoculated with SBV either as cell culture grown virus or as virus with no history of passage in cell cultures...... 3–5 days by real-time RT-PCR. In total, 13 out of 30 inoculated sheep became RNAemic, with the highest viral load in animals inoculated with virus from low cell culture passaged or the animal passaged material. Contact animals remained negative throughout the study. One RNAemic sheep showed...

  4. GM2 gangliosidosis in British Jacob sheep.

    Science.gov (United States)

    Wessels, M E; Holmes, J P; Jeffrey, M; Jackson, M; Mackintosh, A; Kolodny, E H; Zeng, B J; Wang, C B; Scholes, S F E

    2014-01-01

    GM2 gangliosidosis (Tay-Sachs disease) was diagnosed in 6- to 8-month-old pedigree Jacob lambs from two unrelated flocks presenting clinically with progressive neurological dysfunction of 10 day's to 8 week's duration. Clinical signs included hindlimb ataxia and weakness, recumbency and proprioceptive defects. Histopathological examination of the nervous system identified extensive neuronal cytoplasmic accumulation of material that stained with periodic acid--Schiff and Luxol fast blue. Electron microscopy identified membranous cytoplasmic bodies within the nervous system. Serum biochemistry detected a marked decrease in hexosaminidase A activity in the one lamb tested, when compared with the concentration in age matched controls and genetic analysis identified a mutation in the sheep hexa allele G444R consistent with Tay-Sachs disease in Jacob sheep in North America. The identification of Tay-Sachs disease in British Jacob sheep supports previous evidence that the mutation in North American Jacob sheep originated from imported UK stock. PMID:24309906

  5. Technological suitability of sheep milk for processing

    Directory of Open Access Journals (Sweden)

    Romualda Danków

    2011-06-01

    Full Text Available Annual world sheep milk production is estimated at the level of 8.2 million tons and constitutes 1.5% of the total milk production obtained from various species of mammals. Majority of this milk is used to manufacture cheeses and fermented beverages. These products are commonly considered as regional articles and are protected by legal regulations which guarantee their taste and aroma typical for a given region and which they owe to traditional production technologies. In Poland, sheep are reared, primarily, in mountainous areas (Podhale, Bieszczady but also in Wielkopolska and Podlasie. The sheep population in Poland is estimated at 223 000 animals but milk is obtained only from a small number of animals and its annual production is assessed at the level of 1000 t. The nutritional value of sheep milk is higher in comparison with goat or cow milk. Sheep milk protein is characterised by a high biological value comparable with the biological value of the whole chicken egg. In addition, products manufactured from sheep milk possess high nutritive value. Due to its rich chemical composition, sheep milk provides an excellent raw material for processing into maturing soft and hard cheeses (75-80% of protein is casein, for fermented beverages, both natural and with different tastes, as well as butter, ghee and ice-cream. High proportion of dry matter (up to 18% found in sheep milk does not require application of any thickeners in production of fermented beverages. That is why these beverages are fully natural and free of additives.

  6. Briefing note on the sheep industry

    OpenAIRE

    Bruce, Ann

    2012-01-01

    Sheep and beef farmers around the UK were interviewed to find out if they would adopt a range of technologies to reduce methane emissions.* Sheep farmers worked in a range of different environments, some of them very challenging. Farmers talked about a production system that worked for them, in their particular environment and reflecting their particular values. Factors within the system can act as major drivers or barriers to activity. Many perceived that opportunities to do other things tha...

  7. Classically-Controlled Quantum Computation

    OpenAIRE

    Perdrix, Simon; Jorrand, Philippe

    2004-01-01

    Quantum computations usually take place under the control of the classical world. We introduce a Classically-controlled Quantum Turing Machine (CQTM) which is a Turing Machine (TM) with a quantum tape for acting on quantum data, and a classical transition function for a formalized classical control. In CQTM, unitary transformations and measurements are allowed. We show that any classical TM is simulated by a CQTM without loss of efficiency. The gap between classical and quantum computations, ...

  8. Sensitive and specific detection of classical scrapie prions in the brain of goats by real-time quaking-induced conversion

    Science.gov (United States)

    The real-time quaking-induced conversion (RT-QuIC) is a rapid, specific, and sensitive prion seeding activity detection assay that uses recombinant prion protein (rPrPSen) to detect sub-infectious levels of the abnormal isoforms of the prion protein (PrPSc). Although RT-QuIC has been successfully us...

  9. High occurrence of mitochondrial heteroplasmy in nepalese indigenous sheep (Ovis aries) compared to chinese sheep.

    Science.gov (United States)

    Gorkhali, Neena Amatya; Jiang, Lin; Shrestha, Bhola Shankar; He, Xiao-Hong; Junzhao, Qian; Han, Jian-Lin; Ma, Yue-Hui

    2016-07-01

    Heteroplasmy due to length polymorphism with tandem repeats in mtDNAs within individual was hardly studied in domestic animals. In the present study, we identified intra-individual length variation in the control region of mtDNAs in Nepalese sheep by molecular cloning and sequencing techniques. We observed one to four tandem repeats of a 75-bp nucleotide sequences in the mtDNA control region in 45% of the total Nepalese sheep sampled in contrast to the Chinese sheep, indicating that the heteroplasmy is specific to Nepalese sheep. The high rate of heteroplasmy in Nepalese sheep could be a resultant of the mtDNA mutation and independent segregation at intra-individual level or a strand slippage and mispairing during the replication. PMID:26084311

  10. Analysis of Protein Levels of 24 Cytokines in Scrapie Agent-Infected Brain and Glial Cell Cultures from Mice Differing in Prion Protein Expression Levels ▿

    OpenAIRE

    Tribouillard-Tanvier, Déborah; Striebel, James F; Peterson, Karin E.; Chesebro, Bruce

    2009-01-01

    Activation of microglia and astroglia is seen in many neurodegenerative diseases including prion diseases. Activated glial cells produce cytokines as a protective response against certain pathogens and as part of the host inflammatory response to brain damage. In addition, cytokines might also exacerbate tissue damage initiated by other processes. In the present work using multiplex assays to analyze protein levels of 24 cytokines in scrapie agent-infected C57BL/10 mouse brains, we observed e...

  11. Elementary classical hydrodynamics

    CERN Document Server

    Chirgwin, B H; Langford, W J; Maxwell, E A; Plumpton, C

    1967-01-01

    Elementary Classical Hydrodynamics deals with the fundamental principles of elementary classical hydrodynamics, with emphasis on the mechanics of inviscid fluids. Topics covered by this book include direct use of the equations of hydrodynamics, potential flows, two-dimensional fluid motion, waves in liquids, and compressible flows. Some general theorems such as Bernoulli's equation are also considered. This book is comprised of six chapters and begins by introducing the reader to the fundamental principles of fluid hydrodynamics, with emphasis on ways of studying the motion of a fluid. Basic c

  12. Classical mechanics with Maxima

    CERN Document Server

    Timberlake, Todd Keene

    2016-01-01

    This book guides undergraduate students in the use of Maxima—a computer algebra system—in solving problems in classical mechanics. It functions well as a supplement to a typical classical mechanics textbook. When it comes to problems that are too difficult to solve by hand, computer algebra systems that can perform symbolic mathematical manipulations are a valuable tool. Maxima is particularly attractive in that it is open-source, multiple-platform software that students can download and install free of charge. Lessons learned and capabilities developed using Maxima are easily transferred to other, proprietary software.

  13. Classical Holographic Codes

    CERN Document Server

    Brehm, Enrico M

    2016-01-01

    In this work, we introduce classical holographic codes. These can be understood as concatenated probabilistic codes and can be represented as networks uniformly covering hyperbolic space. In particular, classical holographic codes can be interpreted as maps from bulk degrees of freedom to boundary degrees of freedom. Interestingly, they are shown to exhibit features similar to those expected from the AdS/CFT correspondence. Among these are a version of the Ryu-Takayanagi formula and intriguing properties regarding bulk reconstruction and boundary representations of bulk operations. We discuss the relation of our findings with expectations from AdS/CFT and, in particular, with recent results from quantum error correction.

  14. Classic Problems of Probability

    CERN Document Server

    Gorroochurn, Prakash

    2012-01-01

    "A great book, one that I will certainly add to my personal library."—Paul J. Nahin, Professor Emeritus of Electrical Engineering, University of New Hampshire Classic Problems of Probability presents a lively account of the most intriguing aspects of statistics. The book features a large collection of more than thirty classic probability problems which have been carefully selected for their interesting history, the way they have shaped the field, and their counterintuitive nature. From Cardano's 1564 Games of Chance to Jacob Bernoulli's 1713 Golden Theorem to Parrondo's 1996 Perplexin

  15. Learning Classical Music Club

    CERN Multimedia

    Learning Classical Music Club

    2010-01-01

    There is a new CERN Club called “Learning Classical Music at CERN”. We are aiming to give classical music lessons for different instruments (see link) for students from 5 to 100 years old. We are now ready to start our activities in the CERN barracks. We are now in the enrollment phase and hope to start lessons very soon ! Club info can be found in the list of CERN Club: http://user.web.cern.ch/user/Communication/SocialLifeActivities/Clubs/Clubs.html Salvatore Buontempo Club President

  16. Treatment of Scrapie Pathogen 263K With Tetracycline Partially Abolishes Protease-resistant Activity in vitro and Reduces Infectivity in vivo

    Institute of Scientific and Technical Information of China (English)

    YAN-JUN GUO; DE-XIN WANG; XIAO-PING DONG; JUN HAN; HAI-LAN YAO; BAO-YUN ZHANG; JIAN-MEI GAO; JIN ZHANG; XIN-LI XIAO; XIAO-FAN WANG; WEI-QIN ZHAO

    2007-01-01

    Objective To study the possible effect of tetracycline on protease-resistant activity in vitro and infectivity in vivo of a scrapie strain 263K.Methods Scrapie pathogens were incubated with tetracycline at different concentrations for various periods of time and protease-resistant PrP signals were evaluated with proteinase K-treatment and Western blots.The preparations treated with tetracycline were intracerebrally inoculated into golden hamsters and typical TSE manifestations were noted.PrPSc in brain tissues of the infected animals was detected by PrP specific Western blot assays. Results Protease-resistant PrP was significantly reduced in or removed from the preparations treated with tetracycline in a dose-dependant manner.Compared with the control group after incubated for 53.75±0.50 days,the preparations treated with 5 mmol/L and 20 mmol/L tetracycline prolonged the incubation time of 61.5±1.73 and 59.5±0.58 days (P<0.05). Conclusion Treatment of scrapie pathogen 263K with tetracycline reduces or removes its protease-resistant activity in vitro.

  17. Strong Coupling and Classicalization

    CERN Document Server

    Dvali, Gia

    2016-01-01

    Classicalization is a phenomenon in which a theory prevents itself from entering into a strong-coupling regime, by redistributing the energy among many weakly-interacting soft quanta. In this way, the scattering process of some initial hard quanta splits into a large number of soft elementary processes. In short, the theory trades the strong coupling for a high-multiplicity of quanta. At very high energies, the outcome of such a scattering experiment is a production of soft states of high occupation number that are approximately classical. It is evident that black hole creation in particle collision at super-Planckian energies is a result of classicalization, but there is no a priory reason why this phenomenon must be limited to gravity. If the hierarchy problem is solved by classicalization, the LHC has a chance of detecting a tower of new resonances. The lowest-lying resonances must appear right at the strong coupling scale in form of short-lived elementary particles. The heavier members of the tower must b...

  18. Nuclear motion is classical

    CERN Document Server

    Frank, Irmgard

    2016-01-01

    The notion from ab-initio molecular dynamics simulations that nuclear motion is best described by classical Newton dynamics instead of the time-dependent Schr{\\"o}dinger equation is substantiated. In principle a single experiment should bring clarity. Caution is however necessary, as temperature dependent effects must be eliminated when trying to determine the existence of a zero-point energy.

  19. Classics in What Sense?

    Science.gov (United States)

    Camic, Charles

    2008-01-01

    They seem the perfect bookends for the social psychologist's collection of "classics" of the field. Two volumes, nearly identical in shape and weight and exactly a century old in 2008--each professing to usher "social psychology" into the world as they both place the hybrid expression square in their titles but then proceed to stake out the field…

  20. Mecanica Clasica (Classical Mechanics)

    CERN Document Server

    Rosu, H C

    1999-01-01

    First Internet undergraduate course on Classical Mechanics in Spanish (Castellano). This is about 80% of the material I covered during the January-June 1999 semester at IFUG in the Mexican city of Leon. English and Romanian versions are in (slow) progress and hopefully will be arXived. For a similar course on Quantum Mechanics, see physics/9808031

  1. Classical galactosaemia revisited

    NARCIS (Netherlands)

    A.M. Bosch

    2006-01-01

    Classical galactosaemia (McKusick 230400) is an: autosomal recessive disorder of galactose metabolism, caused by a deficiency of the enzyme galactose-1-phosphate uridyltransferase (GALT; EC 2.7.712). Most patients present in the neonatal period, after ingestion of galactose, with jaundice, hepatospl

  2. The Classical Cake Problem

    Science.gov (United States)

    Nelson, Norman N.; Fisch, Forest N.

    1973-01-01

    Discussed are techniques of presentation and solution of the Classical Cake Problem. A frosted cake with a square base is to be cut into n pieces with the volume of cake and frosting the same for each piece. Needed are minimal geometric concepts and the formula for the volume of a prism. (JP)

  3. Classicism and Romanticism.

    Science.gov (United States)

    Huddleston, Gregory H.

    1993-01-01

    Describes one teacher's methods for introducing to secondary English students the concepts of Classicism and Romanticism in relation to pictures of gardens, architecture, music, and literary works. Outlines how the unit leads to a writing assignment based on collected responses over time. (HB)

  4. Classical and quantum satisfiability

    CERN Document Server

    de Araújo, Anderson; 10.4204/EPTCS.81.6

    2012-01-01

    We present the linear algebraic definition of QSAT and propose a direct logical characterization of such a definition. We then prove that this logical version of QSAT is not an extension of classical satisfiability problem (SAT). This shows that QSAT does not allow a direct comparison between the complexity classes NP and QMA, for which SAT and QSAT are respectively complete.

  5. Mecanica Clasica (Classical Mechanics)

    OpenAIRE

    H. C. Rosu

    1999-01-01

    First Internet graduate course on Classical Mechanics in Spanish (Castellano). This is about 80% of the material I covered during the January-June 1999 semester at IFUG in the Mexican city of Leon. English and Romanian versions are in (slow) progress and hopefully will be arXived. For a similar course on Quantum Mechanics, see physics/9808031

  6. Classical Mechanics Laboratory

    Science.gov (United States)

    Brosing, Juliet W.

    2006-12-01

    At Pacific University we have included a lab with our upper division Classical Mechanics class. We do a combination of physical labs (air resistance, harmonic motion, amusement park physics), Maple labs (software), and projects. Presentation of some of the labs, results and challenges with this course will be included.

  7. Classical Mythology. Fourth Edition.

    Science.gov (United States)

    Morford, Mark P. O.; Lenardon, Robert J.

    Designed for students with little or no background in classical literature, this book introduces the Greek and Roman myths of creation, myths of the gods, Greek sagas and local legends, and presents contemporary theories about the myths. Drawing on Homer, Hesiod, Pindar, Vergil, and others, the book provides many translations and paraphrases of…

  8. Children's Classics. Fifth Edition.

    Science.gov (United States)

    Jordan, Alice M.

    "Children's Classics," a 1947 article by Alice M. Jordan reprinted from "The Horn Book Magazine," examines the dynamics and appeal of some of the most famous books for young readers, including "Alice in Wonderland,""The Wind in the Willows,""Robinson Crusoe," and "Andersen's Fairy Tales." Paul Hein's annotated bibliography, a revision of Jordan's…

  9. Proteomic evaluation of sheep serum proteins

    Directory of Open Access Journals (Sweden)

    Chiaradia Elisabetta

    2012-05-01

    Full Text Available Abstract Background The applications of proteomic strategies to ovine medicine remain limited. The definition of serum proteome may be a good tool to identify useful protein biomarkers for recognising sub-clinical conditions and overt disease in sheep. Findings from bovine species are often directly translated for use in ovine medicine. In order to characterize normal protein patterns and improve knowledge of molecular species-specific characteristics, we generated a two-dimensional reference map of sheep serum. The possible application of this approach was tested by analysing serum protein patterns in ewes with mild broncho-pulmonary disease, which is very common in sheep and in the peripartum period which is a stressful time, with a high incidence of infectious and parasitic diseases. Results This study generated the first reference 2-DE maps of sheep serum. Overall, 250 protein spots were analyzed, and 138 identified. Compared with healthy sheep, serum protein profiles of animals with rhino-tracheo-bronchitis showed a significant decrease in protein spots identified as transthyretin, apolipoprotein A1 and a significant increase in spots identified as haptoglobin, endopin 1b and alpha1B glycoprotein. In the peripartum period, haptoglobin, alpha-1-acid glycoprotein, apolipoprotein A1 levels rose, while transthyretin content dropped. Conclusions This study describes applications of proteomics in putative biomarker discovery for early diagnosis as well as for monitoring the physiological and metabolic situations critical for ovine welfare.

  10. A review on prolificacy genes in sheep.

    Science.gov (United States)

    Abdoli, R; Zamani, P; Mirhoseini, S Z; Ghavi Hossein-Zadeh, N; Nadri, S

    2016-10-01

    Ovulation rate and litter size are important reproduction traits in sheep and are of high economic value. Reproduction traits typically have low to medium heritabilities and do not exhibit a noticeable response to phenotypic selection. Therefore, inclusion of genetic information of the genes associated with reproductive ability could efficiently enhance the selection response. The most important major genes affecting prolificacy and their genetic diversities in different sheep breeds were reviewed. Different causative mutations with major effects on reproductive traits including ovulation rate and litter size have been found in various sheep breeds around the world. A general overview of the studies on main prolificacy genes showed that some alleles may express different phenotypic effects in different breeds, and thus, further studies on epistatic effects are necessary for more understanding of genetic control of reproductivity in sheep. Regarding the polygenic control of fertility traits, application of new high-throughput technologies to find new variants is essential for future studies. Moreover, genomewide association studies and genomic best linear unbiased predictions of breeding values are likely to be effective tools for genetic improvement of sheep reproductive performance traits.

  11. The seroprevalence of Toxoplasma gondii in Ontario sheep flocks

    OpenAIRE

    Waltner-Toews, David; Mondesire, Roy; Menzies, Paula

    1991-01-01

    In a random sample of 103 sheep farms in Ontario, 99% of the farms had some sheep serologically positive for Toxoplasma gondii, based on an enzymelinked immunosorbent assay (ELISA). The percent of sheep affected within farms ranged from 3.8% to 97.8%, with an average flock prevalence of 57.6%. When farm management variables were considered in a multivariate analysis, significantly lower rates of serologically positive sheep were associated with neutering of female cats and clipping of ewes' p...

  12. Milk yield and quality of Cres sheep and their crosses with Awassi and East Friesian sheep

    Directory of Open Access Journals (Sweden)

    Boro Mioč

    2009-09-01

    Full Text Available The objective of this study was to establish the impact of crossing the indigenous Cres sheep with Awassi and, respectively, Awassi and East Friesian sheep on the milk yield and quality. For this purpose, through regular monthly milk yield recordings a total of 824individual milk samples from 139 sheep in the second lactation of the same flock were collected, of which: 46 purebred Cres sheep, CS; 33 crosses with 50 % Cres sheep and 50 % Awassi, CA; 60 crosses with 50 % Cres sheep, 25 % Awassi and 25 % East Friesian, CAEF. The obtained results show a significant (P<0.05; P<0.01 impact of the genotype and the lactation stage on the yield and chemical composition of milk, and the somatic cell count. The most milk was yielded by CAEF crosses (690 mL/ewe/day, i.e., 133.8 L per lactation and the least by CS (340 mL/ewe/day, i.e., 58.48 L per lactation. The content of total solids, fat and protein increased as lactation advanced, whereas the trend of the lactose content was opposite. The highest content of total solids, fat and protein were established in the milk of the indigenous Cres sheep. A positive correlation was established between the amount of yielded milk and the somatic cell count, whereas a negative correlation was established between the amount of milk and the content of solids, fat and proteins.

  13. Survival of bighorn sheep (Ovis canadensis) commingled with domestic sheep (Ovis aries) in the absence of Mycoplasma ovipneumoniae.

    Science.gov (United States)

    Besser, Thomas E; Cassirer, E Frances; Yamada, Catherine; Potter, Kathleen A; Herndon, Caroline; Foreyt, William J; Knowles, Donald P; Srikumaran, Subramaniam

    2012-01-01

    To test the hypothesis that Mycoplasma ovipneumoniae is an important agent of the bighorn sheep (Ovis canadensis) pneumonia that has previously inevitably followed experimental commingling with domestic sheep (Ovis aries), we commingled M. ovipneumoniae-free domestic and bighorn sheep (n=4 each). One bighorn sheep died with acute pneumonia 90 days after commingling, but the other three remained healthy for >100 days. This unprecedented survival rate is significantly different (P=0.002) from that of previous bighorn-domestic sheep contact studies but similar to (P>0.05) bighorn sheep survival following commingling with other ungulates. The absence of epizootic respiratory disease in this experiment supports the hypothesized role of M. ovipneumoniae as a key pathogen of epizootic pneumonia in bighorn sheep commingled with domestic sheep.

  14. Breeding strategies to make sheep farms resilient to uncertainty

    NARCIS (Netherlands)

    Rose, I.J.

    2014-01-01

    The sheep industry in Western Australian has had many challenges over the last 20 years which have caused sheep numbers to decline. This decline is because sheep farms are not resilient to uncertain pasture growth and commodity prices. One way to improve resilience and profitability of farming syste

  15. A genome scan to detect QTL affecting dairy traits in a dairy sheep backcross Sarda x Lacaune population

    Directory of Open Access Journals (Sweden)

    L. Mura

    2011-03-01

    Full Text Available Recently in Mediterranean countries as France, Italy and Spain, dairy sheep selection has been efficiently oriented towards milk yield and milk composition. More attention has been now paid to traits related to the reduction of production costs (milkability, functional traits, longevity, health (resistance to mastitis or parasitic diseases, safety of food (reduction in contaminants and quality (milk fatty acids composition. Therefore, research combining classical quantitative approach and QTL detection is needed, either on-farm by implementing experimental recording schemes......

  16. Experimental reproduction of severe bluetongue in sheep.

    Science.gov (United States)

    MacLachlan, N J; Crafford, J E; Vernau, W; Gardner, I A; Goddard, A; Guthrie, A J; Venter, E H

    2008-05-01

    Sheep inoculated with a virulent South African strain of bluetongue (BT) virus serotype 4 developed severe clinical signs and lesions characteristic of fulminant BT, including coronitis, hemorrhage and ulceration of the mucosal lining of the oral cavity and forestomaches, hemorrhage in the wall of the pulmonary artery, and focally extensive necrosis of skeletal muscle, especially of the neck. At necropsy, up to 14 days after infection, the infected sheep exhibited striking pulmonary edema, edema of the subcutaneous tissues and fascial planes of the head and neck, and pleural and pericardial effusion of varying severity. A reliable model for experimental reproduction of fulminant BT in sheep will facilitate future studies to better characterize the pathogenesis of this disease, particularly as it regards the mechanisms responsible for the increased vascular permeability that characterizes BT and related orbiviral diseases such as African horse sickness. PMID:18487487

  17. [Assessment of noise exposure in sheep].

    Science.gov (United States)

    Hauser, R; Wechsler, B

    2013-02-01

    The behaviour of sheep was recorded as a reaction to the sound pressure levels caused by shooting with heavy machine guns. The reactions varied in intensity depending on the distance of the source of the noise from the fold. In the case of salvoes that were fired in the immediate vicinity of the fold and were associated with sound pressure levels higher than 120 dB (LCpeak), the sheep reacted with marked fright reactions, and no adaptation to the shooting noise was observed. It is concluded that the tolerable maximum noise level for sheep with this kind of noise source is likely to be less than 120 dB (LCpeak). PMID:23385071

  18. The classic project

    International Nuclear Information System (INIS)

    Exchange of data and algorithms among accelerator physics programs is difficult because of unnecessary differences in input formats and internal data structures. To alleviate these problems a C++ class library called CLASSIC (Class Library for Accelerator System Simulation and Control) is being developed with the goal to provide standard building blocks for computer programs used in accelerator design. It includes modules for building accelerator lattice structures in computer memory using a standard input language, a graphical user interface, or a programmed algorithm. It also provides simulation algorithms. These can easily be replaced by modules which communicate with the control system of the accelerator. Exchange of both data and algorithm between different programs using the CLASSIC library should present no difficulty

  19. Randomness: quantum versus classical

    CERN Document Server

    Khrennikov, Andrei

    2015-01-01

    Recent tremendous development of quantum information theory led to a number of quantum technological projects, e.g., quantum random generators. This development stimulates a new wave of interest in quantum foundations. One of the most intriguing problems of quantum foundations is elaboration of a consistent and commonly accepted interpretation of quantum state. Closely related problem is clarification of the notion of quantum randomness and its interrelation with classical randomness. In this short review we shall discuss basics of classical theory of randomness (which by itself is very complex and characterized by diversity of approaches) and compare it with irreducible quantum randomness. The second part of this review is devoted to the information interpretation of quantum mechanics (QM) in the spirit of Zeilinger and Brukner (and QBism of Fuchs et al.) and physics in general (e.g., Wheeler's "it from bit") as well as digital philosophy of Chaitin (with historical coupling to ideas of Leibnitz). Finally, w...

  20. Classical and statistical thermodynamics

    CERN Document Server

    Rizk, Hanna A

    2016-01-01

    This is a text book of thermodynamics for the student who seeks thorough training in science or engineering. Systematic and thorough treatment of the fundamental principles rather than presenting the large mass of facts has been stressed. The book includes some of the historical and humanistic background of thermodynamics, but without affecting the continuity of the analytical treatment. For a clearer and more profound understanding of thermodynamics this book is highly recommended. In this respect, the author believes that a sound grounding in classical thermodynamics is an essential prerequisite for the understanding of statistical thermodynamics. Such a book comprising the two wide branches of thermodynamics is in fact unprecedented. Being a written work dealing systematically with the two main branches of thermodynamics, namely classical thermodynamics and statistical thermodynamics, together with some important indexes under only one cover, this treatise is so eminently useful.

  1. Injuries in classical ballet

    Directory of Open Access Journals (Sweden)

    Adriana Coutinho de Azevedo Guimarães

    2008-06-01

    Full Text Available This study aimed to elucidate what injuries are most likely to occur due to classical ballet practice. The research used national and international bibliography. The bibliography analysis indicated that technical and esthetical demands lead to a practice of non-anatomical movements, causing the ballet dancer to suffer from a number of associated lesions. Most of the injuries are caused by technical mistakes and wrong training. Troubles in children are usually due to trying to force external rotation at hip level and to undue use of point ballet slippers. The commonest lesions are in feet and ankles, followed by knees and hips. The rarest ones are in the upper limbs. These injuries are caused by exercise excess, by repetitions always in the same side and by wrong and early use of point slippers. The study reached the conclusion that incorrect application of classical ballet technique predisposes the dancers to characteristic injuries.

  2. Classical Diophantine equations

    CERN Document Server

    1993-01-01

    The author had initiated a revision and translation of "Classical Diophantine Equations" prior to his death. Given the rapid advances in transcendence theory and diophantine approximation over recent years, one might fear that the present work, originally published in Russian in 1982, is mostly superseded. That is not so. A certain amount of updating had been prepared by the author himself before his untimely death. Some further revision was prepared by close colleagues. The first seven chapters provide a detailed, virtually exhaustive, discussion of the theory of lower bounds for linear forms in the logarithms of algebraic numbers and its applications to obtaining upper bounds for solutions to the eponymous classical diophantine equations. The detail may seem stark--- the author fears that the reader may react much as does the tourist on first seeing the centre Pompidou; notwithstanding that, Sprind zuk maintainsa pleasant and chatty approach, full of wise and interesting remarks. His emphases well warrant, ...

  3. Classical Weyl Transverse Gravity

    CERN Document Server

    Oda, Ichiro

    2016-01-01

    We study various classical aspects of the Weyl transverse (WTDiff) gravity in a general space-time dimension. First of all, we clarify a classical equivalence among three kinds of gravitational theories, those are, the conformally-invariant scalar tensor gravity, Einstein's general relativity and the WTDiff gravity via the gauge fixing procedure. Secondly, we show that in the WTDiff gravity the cosmological constant is a mere integration constant as in unimodular gravity, but it does not receive any radiative corrections unlike the unimodular gravity. A key point in this proof is to construct a covariantly conserved energy-momentum tensor, which is achieved on the basis of this equivalence relation. Thirdly, we demonstrate that the Noether current for the Weyl transformation is identically vanishing, thereby implying that the Weyl symmetry existing in both the conformally-invariant scalar tensor gravity and the WTDiff gravity is a "fake" symmetry. We find it possible to extend this proof to all matter fields,...

  4. Computation in Classical Mechanics

    CERN Document Server

    Timberlake, Todd

    2007-01-01

    There is a growing consensus that physics majors need to learn computational skills, but many departments are still devoid of computation in their physics curriculum. Some departments may lack the resources or commitment to create a dedicated course or program in computational physics. One way around this difficulty is to include computation in a standard upper-level physics course. An intermediate classical mechanics course is particularly well suited for including computation. We discuss the ways we have used computation in our classical mechanics courses, focusing on how computational work can improve students' understanding of physics as well as their computational skills. We present examples of computational problems that serve these two purposes. In addition, we provide information about resources for instructors who would like to include computation in their courses.

  5. Tay-Sachs disease in Jacob sheep.

    Science.gov (United States)

    Torres, Paola A; Zeng, Bai Jin; Porter, Brian F; Alroy, Joseph; Horak, Fred; Horak, Joan; Kolodny, Edwin H

    2010-12-01

    Autopsy studies of four Jacob sheep dying within their first 6-8 months of a progressive neurodegenerative disorder suggested the presence of a neuronal storage disease. Lysosomal enzyme studies of brain and liver from an affected animal revealed diminished activity of hexosaminidase A (Hex A) measured with an artificial substrate specific for this component of β-hexosaminidase. Absence of Hex A activity was confirmed by cellulose acetate electrophoresis. Brain lipid analyses demonstrated the presence of increased concentrations of G(M2)-ganglioside and asialo-G(M2)-ganglioside. The hexa cDNA of Jacob sheep was cloned and sequenced revealing an identical number of nucleotides and exons as in human HexA and 86% homology in nucleotide sequence. A missense mutation was found in the hexa cDNA of the affected sheep caused by a single nucleotide change at the end of exon 11 resulting in skipping of exon 11. Transfection of normal sheep hexa cDNA into COS1 cells and human Hex A-deficient cells led to expression of Hex S but no increase in Hex A indicating absence of cross-species dimerization of sheep Hex α-subunit with human Hex β-subunits. Using restriction site analysis, the heterozygote frequency of this mutation in Jacob sheep was determined in three geographically separate flocks to average 14%. This large naturally occurring animal model of Tay-Sachs disease is the first to offer promise as a means for trials of gene therapy applicable to human infants. PMID:20817517

  6. Concepts of classical optics

    CERN Document Server

    Strong, John

    2004-01-01

    An intermediate course in optics, this volume explores both experimental and theoretical concepts, offering practical knowledge of geometrical optics that will enhance students' comprehension of any relevant applied science. Its exposition of the concepts of classical optics is presented with a minimum of mathematical detail but presumes some knowledge of calculus, vectors, and complex numbers.Subjects include light as wave motion; superposition of wave motions; electromagnetic waves; interaction of light and matter; velocities and scattering of light; polarized light and dielectric boundarie

  7. Sociology and Classical Liberalism

    OpenAIRE

    KLEIN, Daniel; Stern, Lotta

    2005-01-01

    We advocate the development of a classical-liberal character within professional sociology. The American Sociological Association (ASA) is taken as representative of professional sociology in the United States. We review the ASA’s activities and organizational statements, to show the association’s leftist character. Internal criticism is often very uneasy about leftist domination of the field. We present survey results establishing that, in voting and in policy views, the ASA membership is mo...

  8. Revisiting a Classic

    Science.gov (United States)

    Rogers, Ibram

    2008-01-01

    As a 26-year-old English teacher in 1958, Chinua Achebe had no idea that the book he was writing would become a literary classic, not only in Africa but also throughout the world. He could only try to articulate the feelings he had for his countrymen and women. Achebe had a burning desire to tell the true story of Africa and African humanity. The…

  9. Injuries in classical ballet

    OpenAIRE

    Adriana Coutinho de Azevedo Guimarães; Joseani Paulini Neves Simas

    2008-01-01

    This study aimed to elucidate what injuries are most likely to occur due to classical ballet practice. The research used national and international bibliography. The bibliography analysis indicated that technical and esthetical demands lead to a practice of non-anatomical movements, causing the ballet dancer to suffer from a number of associated lesions. Most of the injuries are caused by technical mistakes and wrong training. Troubles in children are usually due to trying to force external ...

  10. A Classic's New Charm

    Institute of Scientific and Technical Information of China (English)

    WANG HAIRONG

    2010-01-01

    @@ North Korea's Phibada Opera Troupe arrived in Beijing on May3,bringing with it a Korean opera adapted from China's classic novel A Dream of Red Mansions written by Cao Xueqin(around 1715-63),a great novelist of the Qing Dynasty(1644-1911).The troupe,invited by the Chinese Ministry of Culture,is one of the largest performing groups having visited China in recent years.

  11. Diffusion of Classical Solitons

    OpenAIRE

    Dziarmaga, J.; Zakrzewski, W.

    1998-01-01

    We study the diffusion and deformation of classical solitons coupled to thermal noise. The diffusion coefficient for kinks in the $\\phi^4$ theory is predicted up to the second order in $kT$. The prediction is verified by numerical simulations. Multiskyrmions in the vector O(3) sigma model are studied within the same formalism. Thermal noise results in a diffusion on the multisoliton collective coordinate space (moduli space). There are entropic forces which tend, for example, to bind pairs of...

  12. Classical Maxwellian polarization entanglement

    CERN Document Server

    Carroll, John E

    2015-01-01

    An explanation of polarization entanglement is presented using Maxwells classical electromagnetic theory.Two key features are required to understand these classical origins.The first is that all waves diffract and weakly diffracting waves,with a principal direction of propagation in the laboratory frame, travel along that direction at speeds ever so slightly less than c.This allows nontrivial Lorentz transformations that can act on selected forward F waves or selected waves R traveling in the opposite direction to show that both can arise from a single zero momentum frame where all the waves are transverse to the original principal direction.Such F and R waves then both belong to a single relativistic entity where correlations between the two are unremarkable.The second feature requires the avoidance of using the Coulomb gauge.Waves, tending to plane waves in the limit of zero diffraction,can then be shown to be composed of two coupled sets of E and B fields that demonstrate the classical entanglement of F an...

  13. Survival of bighorn sheep (Ovis canadensis) commingled with domestic sheep (Ovis aries) in the absence of mycoplasma ovipneumoniae.

    Science.gov (United States)

    To test the hypothesis that Mycoplasma ovipneumoniae is an important agent of the bighorn sheep (Ovis canadensis) pneumonia that has previously inevitably followed experimental commingling with domestic sheep (Ovis aries), we commingled M. ovipneumoniae–free domestic and bighorn sheep (n=4 each). On...

  14. 9 CFR 98.10a - Embryos from sheep in regions other than Australia, Canada, and New Zealand.

    Science.gov (United States)

    2010-01-01

    ... participates in the Voluntary Scrapie Flock Certification Program (see 9 CFR part 54, subpart B) and qualifies... that participates in the Voluntary Scrapie Flock Certification Program (see 9 CFR part 54, subpart B... Certification Program authorized under 9 CFR part 54, subpart B.” (1) The Administrator will determine,...

  15. Toxoplasmosis of Goat and Sheep in Java

    OpenAIRE

    Tolibin Iskandar

    2008-01-01

    Toxoplasmosis is a parasitic disease, caused by Toxoplasma gondii attacking goat, sheep, and wild animals. This disease is zoonosis and widely distributed in many districts of Java and as a zoonotic disease. Cat is the definitive host of T. gondii, while sheep, goats, and humans are the intermediate hosts. The prevalence of toxoplasmosis in Java was between 7 to 84%, with an average of 42.9%. It occurs through out of the year and causes abortions and infertilities of infected animals. All bre...

  16. Enzootic calcinosis caused by Nierembergia rivularis in sheep.

    Science.gov (United States)

    García y Santos, Carmen; Pereira, Rodrigo; Etcheberry, Gabriel; Goyen, Juan M; Pérez, William; Capelli, Alejandra; Alonso, Eduardo; Ruiz-Díaz, Alejandro; Riet-Correa, Franklin

    2012-03-01

    Enzootic calcinosis was diagnosed in sheep in Uruguay in pastures containing the plant Nierembergia rivularis. In a flock of 200 sheep, 20 were affected and 12 died. Clinical signs were anorexia, weight loss followed by cachexia, stiffness, and kyphosis. At necropsy and histologic examination, mineral deposits were observed on the medial layer of the arteries, heart, lungs, and kidneys. Similar lesions were also observed in 3 sheep forced to graze in an area containing the plant, while no lesions were observed in a control sheep that grazed in an area free of N. rivularis. It is concluded that N. rivularis is a calcinogenic plant for sheep. PMID:22379059

  17. A reversal phase arrest uncoupling the bone formation and resorption contributes to the bone loss in glucocorticoid treated ovariectomised aged sheep.

    Science.gov (United States)

    Andreasen, Christina M; Ding, Ming; Overgaard, Søren; Bollen, Peter; Andersen, Thomas L

    2015-06-01

    Large animals as sheep are often used as models for human osteoporosis. Our aim was therefore to determine how glucocorticoid treatment of ovariectomised sheep affects the cancellous bone, determining the cellular events within the bone remodelling process that contributes to their bone loss. Twenty female sheep were assigned for two groups; an untreated control group and an ovariectomised group treated with glucocorticoids (0.6 mg/kg/day, 5 times weekly) for 7 months. At 7 months the glucocorticoid-treated ovariectomised sheep showed a significant change in the bone microstructure revealed by a decreased trabecular bone volume and thickness compared to the control sheep. The treatment led to a temporary elevation of the bone resorption marker CTX (c-terminal collagen telopeptide), while the bone formation marker osteocalcin remained suppressed all 7 months. Histomorphometrically, the treated sheep had a complete absence of osteoid surfaces, and a 5-fold increase in the extent of eroded/reversal surfaces after 7 months. Most of these reversal surfaces were actually arrested reversal surfaces, defined as reversal surfaces without the presence of neighbouring osteoid surfaces or osteoclasts, which is classically observed next to active reversal surfaces. As in humans, these arrested reversal surfaces had compared to active reversal surfaces a reduced canopy coverage, a significantly decreased cell density, and a decreased immunoreactivity for the osteoblastic markers osterix, runx2 and smooth muscle actin in the mononuclear reversal cells colonising the surfaces. In conclusion, glucocorticoid treatment of ovariectomised sheep induced a significant bone loss, caused by an arrest of the reversal phase, resulting in an uncoupling of the bone formation and resorption during the reversal phase, as recently demonstrated in postmenopausal women with glucocorticoid-induced osteoporosis. This supports the relevance of the sheep model to the pathophysiology of glucocorticoid

  18. Minimum Effective Dose of Cattle and Sheep BSE for Oral Sheep Infection.

    Directory of Open Access Journals (Sweden)

    Gillian McGovern

    Full Text Available The minimum dose required to cause infection of Romney and Suffolk sheep of the ARQ/ARQ or ARQ/ARR prion protein gene genotypes following oral inoculation with Romney or Suffolk a sheep Bovine spongiform encephalopathy (BSE-derived or cattle BSE-derived agent was investigated using doses ranging from 0.0005g to 5g. ARQ/ARQ sheep which were methionine (M / threonine (T heterozygous or T/T homozygous at codon 112 of the Prnp gene, dosed ARQ/ARR sheep and undosed controls did not show any evidence of infection. Within groups of susceptible sheep, the minimum effective oral dose of BSE was found to be 0.05g, with higher attack rates following inoculation with the 5g dose. Surprisingly, this study found no effect of dose on survival time suggesting a possible lack of homogeneity within the inoculum. All clinical BSE cases showed PrPd accumulation in brain; however, following cattle BSE inoculation, LRS involvement within Romney recipients was found to be significantly lower than within the Suffolk sheep inoculated group which is in agreement with previous reports.

  19. On Classical Ideal Gases

    Directory of Open Access Journals (Sweden)

    Laurent Chusseau

    2013-02-01

    Full Text Available We show that the thermodynamics of ideal gases may be derived solely from the Democritean concept of corpuscles moving in vacuum plus a principle of simplicity, namely that these laws are independent of the laws of motion, aside from the law of energy conservation. Only a single corpuscle in contact with a heat bath submitted to a z and t-invariant force is considered. Most of the end results are known but the method appears to be novel. The mathematics being elementary, the present paper should facilitate the understanding of the ideal gas law and of classical thermodynamics even though not-usually-taught concepts are being introduced.

  20. A Classic Through Eternity

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    FIVE years ago, an ancient Chinese air was beamed to outer space as a PR exercise. To humankind, music is a universal language, so the tune seemed an ideal medium for communication with extraterrestrial intelligence. So far there has been no response, but it is believed that the tune will play for a billion years, and eventually be heard and understood. The melody is called High Mountain and Flowing Stream, and it is played on the guqin, a seven-stringed classical musical instrument similar to the zither.

  1. Mechanics classical and quantum

    CERN Document Server

    Taylor, T T

    2015-01-01

    Mechanics: Classical and Quantum explains the principles of quantum mechanics via the medium of analytical mechanics. The book describes Schrodinger's formulation, the Hamilton-Jacobi equation, and the Lagrangian formulation. The author discusses the Harmonic Oscillator, the generalized coordinates, velocities, as well as the application of the Lagrangian formulation to systems that are partially or entirely electromagnetic in character under certain conditions. The book examines waves on a string under tension, the isothermal cavity radiation, and the Rayleigh-Jeans result pertaining to the e

  2. Close interactions between sympathetic neural fibres and follicular dendritic cells network are not altered in Peyer's patches and spleen of C57BL/6 mice during the preclinical stage of 139A scrapie infection.

    Science.gov (United States)

    Demonceau, Caroline; Piret, Joelle; Zorzi, Danièle; Thellin, Olivier; Heinen, Ernst

    2014-07-15

    During preclinical stage of prion diseases, secondary lymphoid organs seem to play an important role in prion amplification prior the invasion of the associated peripheral nervous system. In mice, it was shown that the relative positioning of follicular dendritic cells (FDC) and sympathetic nervous system (SNS) affects the velocity of neuroinvasion following scrapie inoculation. In this study, we checked if scrapie infection, by oral or intraperitoneal route, could influence this neuroimmune interface between FDC and tyrosine hydroxylase (TH) positive neural fibres within Peyer's patches (PP) and spleen of the C57BL/6 mouse strain. We concluded that, in vivo, scrapie 139A and ME7 strains do not modify FDC-SNS neuroimmune interface. However, age seems to alter this neuroimmune interface and thus could influence the neuroinvasion in prion pathogenesis. PMID:24841625

  3. Monensin toxicosis in 2 sheep flocks.

    OpenAIRE

    Jones, A.

    2001-01-01

    Several lambs in 2 sheep flocks died suddenly and others were examined for generalized weakness and dyspnea. Postmortem findings were suggestive of degenerative myocardial and skeletal muscle myopathy, which was confirmed histologically. Feed analysis revealed toxic levels of monensin and ionophore toxicosis was diagnosed.

  4. Analysis of wolves and sheep. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Hogden, J.; Papcun, G.; Zlokarnik, I.; Nix, D.

    1997-08-01

    In evaluating speaker verification systems, asymmetries have been observed in the ease with which people are able to break into other people`s voice locks. People who are good at breaking into voice locks are called wolves, and people whose locks are easy to break into are called sheep. (Goats are people that have a difficult time opening their own voice locks.) Analyses of speaker verification algorithms could be used to understand wolf/sheep asymmetries. Using the notion of a ``speaker space``, it is demonstrated that such asymmetries could arise even though the similarity of voice 1 to voice 2 is the same as the inverse similarity. This explains partially the wolf/sheep asymmetries, although there may be other factors. The speaker space can be computed from interspeaker similarity data using multidimensional scaling, and such speaker space can be used to given a good approximation of the interspeaker similarities. The derived speaker space can be used to predict which of the enrolled speakers are likely to be wolves and which are likely to be sheep. However, a speaker must first enroll in the speaker key system and then be compared to each of the other speakers; a good estimate of a person`s speaker space position could be obtained using only a speech sample.

  5. Coxiella burnetii infections in sheep or goats

    NARCIS (Netherlands)

    Brom, Van den R.; Engelen, van E.; Roest, H.I.J.; Hoek, van der W.; Vellema, P.

    2015-01-01

    Q fever is an almost ubiquitous zoonosis caused by Coxiella burnetii, which is able to infect several animal species, as well as humans. Cattle, sheep and goats are the primary animal reservoirs. In small ruminants, infections are mostly without clinical symptoms, however, abortions and stillbirt

  6. 9 CFR 91.8 - Sheep.

    Science.gov (United States)

    2010-01-01

    ...-positive animal or an exposed animal, as defined in 9 CFR parts 54 and 79, or if it has ever been in an infected flock, source flock, or trace flock, as defined in 9 CFR parts 54 and 79; or if it is the progeny... be identified by eartags or tattoos approved by the Administrator. 3 except that sheep for export...

  7. Dynamics of Sheep Production in Brazil

    Directory of Open Access Journals (Sweden)

    Samuel Rezende Paiva

    2013-07-01

    Full Text Available Sheep production is present on all continents and has been practiced in Brazil since the colonization. In this study, the multitemporal dynamics of sheep production in Brazil is examined using official government data (Brazilian Institute for Geography and Statistics-IBGE from 1976 to 2010. Maps of flock growth rates and growth acceleration maps by municipality were elaborated. The Southern states are seen to show a reduction in production mainly due to the wool crisis in the 1970s and 80s. The Northeast is seen to be important for meat production. More recently, centerwest and northern states have shown an increase in growth rates but this is still incipient. The maps of growth, acceleration and midpoint for sheep production showed a noticeable return to an increase in production in the South in recent years. The midpoint of production flow was in the northeast direction, which has stagnated. There was great dynamics in sheep production over the whole Brazilian territory, which affected supply chains due to the expansion of domestic and foreign markets. Areas with higher fluctuations in production are more vulnerable in terms of investment policies.

  8. Probability representation of classical states

    NARCIS (Netherlands)

    Man'ko, OV; Man'ko, [No Value; Pilyavets, OV

    2005-01-01

    Probability representation of classical states described by symplectic tomograms is discussed. Tomographic symbols of classical observables which are functions on phase-space are studied. Explicit form of kernel of commutative star-product of the tomographic symbols is obtained.

  9. Variability of the Sheep Lung Microbiota

    Science.gov (United States)

    Wright, Steven; Pollock, Jolinda; Tennant, Peter; Collie, David; McLachlan, Gerry

    2016-01-01

    ABSTRACT Sequencing technologies have recently facilitated the characterization of bacterial communities present in lungs during health and disease. However, there is currently a dearth of information concerning the variability of such data in health both between and within subjects. This study seeks to examine such variability using healthy adult sheep as our model system. Protected specimen brush samples were collected from three spatially disparate segmental bronchi of six adult sheep (age, 20 months) on three occasions (day 0, 1 month, and 3 months). To further explore the spatial variability of the microbiotas, more-extensive brushing samples (n = 16) and a throat swab were taken from a separate sheep. The V2 and V3 hypervariable regions of the bacterial 16S rRNA genes were amplified and sequenced via Illumina MiSeq. DNA sequences were analyzed using the mothur software package. Quantitative PCR was performed to quantify total bacterial DNA. Some sheep lungs contained dramatically different bacterial communities at different sampling sites, whereas in others, airway microbiotas appeared similar across the lung. In our spatial variability study, we observed clustering related to the depth within the lung from which samples were taken. Lung depth refers to increasing distance from the glottis, progressing in a caudal direction. We conclude that both host influence and local factors have impacts on the composition of the sheep lung microbiota. IMPORTANCE Until recently, it was assumed that the lungs were a sterile environment which was colonized by microbes only during disease. However, recent studies using sequencing technologies have found that there is a small population of bacteria which exists in the lung during health, referred to as the “lung microbiota.” In this study, we characterize the variability of the lung microbiotas of healthy sheep. Sheep not only are economically important animals but also are often used as large animal models of human

  10. Differential gene expression in ovaries of Qira black sheep and Hetian sheep using RNA-Seq technique.

    Directory of Open Access Journals (Sweden)

    Han Ying Chen

    Full Text Available The Qira black sheep and the Hetian sheep are two local breeds in the Northwest of China, which are characterized by high-fecundity and low-fecundity breed respectively. The elucidation of mRNA expression profiles in the ovaries among different sheep breeds representing fecundity extremes will helpful for identification and utilization of major prolificacy genes in sheep. In the present study, we performed RNA-seq technology to compare the difference in ovarian mRNA expression profiles between Qira black sheep and Hetian sheep. From the Qira black sheep and the Hetian sheep libraries, we obtained a total of 11,747,582 and 11,879,968 sequencing reads, respectively. After aligning to the reference sequences, the two libraries included 16,763 and 16,814 genes respectively. A total of 1,252 genes were significantly differentially expressed at Hetian sheep compared with Qira black sheep. Eight differentially expressed genes were randomly selected for validation by real-time RT-PCR. This study provides a basic data for future research of the sheep reproduction.

  11. Numerical calculation of classical and non-classical electrostatic potentials

    CERN Document Server

    Christensen, D; Neyenhuis, B; Christensen, Dan; Durfee, Dallin S.; Neyenhuis, Brian

    2006-01-01

    We present a numerical exercise in which classical and non-classical electrostatic potentials were calculated. The non-classical fields take into account effects due to a possible non-zero photon rest mass. We show that in the limit of small photon rest mass, both the classical and non-classical potential can be found by solving Poisson's equation twice, using the first calculation as a source term in the second calculation. Our results support the assumptions in a recent proposal to use ion interferometry to search for a non-zero photon rest mass.

  12. Classical Physics and Quantum Loops

    Energy Technology Data Exchange (ETDEWEB)

    Barry R. Holstein; John F. Donoghue

    2004-05-01

    The standard picture of the loop expansion associates a factor of h-bar with each loop, suggesting that the tree diagrams are to be associated with classical physics, while loop effects are quantum mechanical in nature. We discuss examples wherein classical effects arise from loop contributions and display the relationship between the classical terms and the long range effects of massless particles.

  13. Fano Interference in Classical Oscillators

    Science.gov (United States)

    Satpathy, S.; Roy, A.; Mohapatra, A.

    2012-01-01

    We seek to illustrate Fano interference in a classical coupled oscillator by using classical analogues of the atom-laser interaction. We present an analogy between the dressed state picture of coherent atom-laser interaction and a classical coupled oscillator. The Autler-Townes splitting due to the atom-laser interaction is analogous to the…

  14. Characterization of attaching and effacing Escherichia coli (AEEC isolated from pigs and sheep

    Directory of Open Access Journals (Sweden)

    Beutin Lothar

    2008-09-01

    Full Text Available Abstract Background Attaching and effacing Escherichia coli (AEEC are characterized by their ability to cause attaching-and-effacing (A/E lesions in the gut mucosa of human and animal hosts leading to diarrhoea. The genetic determinants for the production of A/E lesions are located on the locus of enterocyte effacement (LEE, a pathogenicity island that also contains the genes encoding intimin (eae. This study reports data on the occurrence of eae positive E. coli carried by healthy pigs and sheep at the point of slaughter, and on serotypes, intimin variants, and further virulence factors of isolated AEEC strains. Results Faecal samples from 198 finished pigs and 279 sheep were examined at slaughter. The proportion of eae positive samples was 89% for pigs and 55% for sheep. By colony dot-blot hybridization, AEEC were isolated from 50 and 53 randomly selected porcine and ovine samples and further characterized. Strains of the serotypes O2:H40, O3:H8 and O26:H11 were found in both pigs and sheep. In pigs O2:H40, O2:H49, O108:H9, O145:H28 and in sheep O2:H40, O26:H11, O70:H40, O146:H21 were the most prevalent serotypes among typable strains. Eleven different intimin types were detected, whereas γ2/θ was the most frequent, followed by β1, ε and γ1. All but two ovine strains tested negative for the genes encoding Shiga toxins. All strains tested negative for the bfpA gene and the EAF plasmid. EAST1 (astA was present in 18 of the isolated strains. Conclusion Our data show that pigs and sheep are a source of serologically and genetically diverse intimin-harbouring E. coli strains. Most of the strains show characteristics of atypical enteropathogenic E. coli. Nevertheless, there are stx-negative AEEC strains belonging to serotypes and intimin types that are associated with classical enterohaemorrhagic E. coli strains (O26:H11, β1; O145:H28, γ1.

  15. Creutzfeldt-Jakob disease a case report, with special attention to the electroencephalogram in this disorder and to its possible relationships to kuru, scrapie and «mad cow disease»

    OpenAIRE

    A.H. Chapman; Djalma Vieira e Silva

    1993-01-01

    A case of Creutzfeldt-Jakob disease in a 58-year-old Brazillian cattle rancher and businessman is presented. The EEG was normal, which is consistent with the fact that it was made during the first half of his illness; in a later stage suppression of normal rhythms by slow moderate voltage waves would be expected. The resemblances of kuru, scrapie and "mad cow disease» to C-J disease are discussed. In each of these 4 illnesses the patient or affected animal (scrapie and «mad cow disease") (a) ...

  16. Accumulation and aberrant composition of cholesteryl esters in Scrapie-infected N2a cells and C57BL/6 mouse brains

    Directory of Open Access Journals (Sweden)

    Di Bari Michele A

    2011-08-01

    Full Text Available Abstract Objective Cholesterol changes have been described in prion-cell models and in experimental rodent scrapie; yet, the pattern of this association is still controversial. Methods To shed light on the matter, we analysed and compared cholesterol variations in ScN2a cells and in brains of Scrapie-infected C57Bl/6 mice, using two different methods: a fluorimetric-enzymatic cholesterol assay, and high performance liquid chromatography-mass spectroscopy (HPLC-MS. Results Compared to uninfected controls, similar cholesterol metabolism anomalies were observed in infected cells and brains by both methods; however, only HPLC-MS revealed statistically significant cholesterol variations, particularly in the cholesteryl esters (CE fraction. HPLC-MS analyses also revealed different fatty acid composition of the CE fraction in cells and brains. In N2a cells, their profile reflected that of serum, while in normal brains cholesteryl-linoleate only was found at detectable levels. Following prion infection, most CE species were increased in the CE pool of ScN2a cells, whereas a conspicuous amount of cholesteryl-arachidonate only was found to contribute to the cerebral increase of CE. Of interest, oral pravastatin administration to Scrapie-infected mice, was associated with a significant reduction of cerebral free cholesterol (FC along with a concomitant further increase of the CE pool, which included increased amounts of both cholesteryl-linoleate and cholesteryl-arachidonate. Conclusion Although mechanistic studies are needed to establish the pathophysiological relevance of changes in cerebral CE concentrations, to the best of our knowledge this is the first report to provide evidence of increased cholesterol esterification in brains of prion-infected mice, untreated and treated with pravastatin.

  17. Mitochondrial DNA variation of domestic sheep (Ovis aries) in Kenya.

    Science.gov (United States)

    Resende, Adriana; Gonçalves, Joana; Muigai, Anne W T; Pereira, Filipe

    2016-06-01

    The history of domestic sheep (Ovis aries) in Africa remains largely unknown. After being first introduced from the Near East, sheep gradually spread through the African continent with pastoral societies. The eastern part of Africa was important either for the first diffusion of sheep southward or for putative secondary introductions from the Arabian Peninsula or southern Asia. We analysed mitochondrial DNA control region sequences of 91 domestic sheep from Kenya and found a high diversity of matrilines from the widespread haplogroup B, whereas only a single individual from haplogroup A was detected. Our phylogeography analyses of more than 500 available mitochondrial DNA sequences also identified ancestral haplotypes that were probably first introduced in Africa and are now widely distributed. Moreover, we found no evidence of an admixture between East and West African sheep. The presence of shared haplotypes in eastern and ancient southern African sheep suggests the possible southward movement of sheep along the eastern part of Africa. Finally, we found no evidence of an extensive introduction of sheep from southern Asia into Africa via the Indian Ocean trade. The overall findings on the phylogeography of East African domestic sheep set the grounds for understanding the origin and subsequent movements of sheep in Africa. The richness of maternal lineages in Kenyan breeds is of prime importance for future conservation and breeding programmes. PMID:26765790

  18. Nucleosynthesis in classical novae

    Science.gov (United States)

    José, Jordi; Hernanz, Margarita; Iliadis, Christian

    2006-10-01

    Classical novae are dramatic stellar explosions with an energy release that is only overcome by supernovae and gamma-ray bursts. These unique cataclysmic events constitute a crucible where different scientific disciplines merge, including astrophysics, nuclear and atomic physics, cosmochemistry, high-energy physics or computer science. In this review, we focus on the nucleosynthesis accompanying nova outbursts. Theoretical predictions are compared with the elemental abundances inferred from observations of the nova ejecta as well as with the isotopic abundance ratios measured in meteorites. Special emphasis is given to the interplay between nova outbursts and the Galactic abundance pattern and on the synthesis of radioactive nuclei for which γ-ray signals are expected. Finally, we analyze the key role played by nuclear physics in our understanding of the nova phenomenon by means of recent experiments and a thorough account of the impact of nuclear uncertainties.

  19. Mechanical Systems, Classical Models

    CERN Document Server

    Teodorescu, Petre P

    2009-01-01

    This third volume completes the Work Mechanical Systems, Classical Models. The first two volumes dealt with particle dynamics and with discrete and continuous mechanical systems. The present volume studies analytical mechanics. Topics like Lagrangian and Hamiltonian mechanics, the Hamilton-Jacobi method, and a study of systems with separate variables are thoroughly discussed. Also included are variational principles and canonical transformations, integral invariants and exterior differential calculus, and particular attention is given to non-holonomic mechanical systems. The author explains in detail all important aspects of the science of mechanics, regarded as a natural science, and shows how they are useful in understanding important natural phenomena and solving problems of interest in applied and engineering sciences. Professor Teodorescu has spent more than fifty years as a Professor of Mechanics at the University of Bucharest and this book relies on the extensive literature on the subject as well as th...

  20. Grassmannization of classical models

    CERN Document Server

    Pollet, Lode; Prokof'ev, Nikolay V; Svistunov, Boris V

    2016-01-01

    Applying Feynman diagrammatics to non-fermionic strongly correlated models with local constraints might seem generically impossible for two separate reasons: (i) the necessity to have a Gaussian (non-interacting) limit on top of which the perturbative diagrammatic expansion is generated by Wick's theorem, and (ii) the Dyson's collapse argument implying that the expansion in powers of coupling constant is divergent. We show that for arbitrary classical lattice models both problems can be solved/circumvented by reformulating the high-temperature expansion (more generally, any discrete representation of the model) in terms of Grassmann integrals. Discrete variables residing on either links, plaquettes, or sites of the lattice are associated with the Grassmann variables in such a way that the partition function (and correlations) of the original system and its Grassmann-field counterpart are identical. The expansion of the latter around its Gaussian point generates Feynman diagrams. A proof-of-principle implement...

  1. Prion seeding activities of mouse scrapie strains with divergent PrPSc protease sensitivities and amyloid plaque content using RT-QuIC and eQuIC.

    Directory of Open Access Journals (Sweden)

    Sarah Vascellari

    Full Text Available Different transmissible spongiform encephalopathy (TSE-associated forms of prion protein (e.g. PrP(Sc can vary markedly in ultrastructure and biochemical characteristics, but each is propagated in the host. PrP(Sc propagation involves conversion from its normal isoform, PrP(C, by a seeded or templated polymerization mechanism. Such a mechanism is also the basis of the RT-QuIC and eQuIC prion assays which use recombinant PrP (rPrP(Sen as a substrate. These ultrasensitive detection assays have been developed for TSE prions of several host species and sample tissues, but not for murine models which are central to TSE pathogenesis research. Here we have adapted RT-QuIC and eQuIC to various murine prions and evaluated how seeding activity depends on glycophosphatidylinositol (GPI anchoring and the abundance of amyloid plaques and protease-resistant PrP(Sc (PrP(Res. Scrapie brain dilutions up to 10(-8 and 10(-13 were detected by RT-QuIC and eQuIC, respectively. Comparisons of scrapie-affected wild-type mice and transgenic mice expressing GPI anchorless PrP showed that, although similar concentrations of seeding activity accumulated in brain, the heavily amyloid-laden anchorless mouse tissue seeded more rapid reactions. Next we compared seeding activities in the brains of mice with similar infectivity titers, but widely divergent PrP(Res levels. For this purpose we compared the 263K and 139A scrapie strains in transgenic mice expressing P101L PrP(C. Although the brains of 263K-affected mice had little immunoblot-detectable PrP(Res, RT-QuIC indicated that seeding activity was comparable to that associated with a high-PrP(Res strain, 139A. Thus, in this comparison, RT-QuIC seeding activity correlated more closely with infectivity than with PrP(Res levels. We also found that eQuIC, which incorporates a PrP(Sc immunoprecipitation step, detected seeding activity in plasma from wild-type and anchorless PrP transgenic mice inoculated with 22L, 79A and/or RML

  2. Citation classics in epilepsy

    Directory of Open Access Journals (Sweden)

    Maryann Wilson

    2013-01-01

    Full Text Available BACKGROUND: The impact of a scientific article is proportional to the citations it has received. In this study, we set out to identify the most cited works in epileptology in order to evaluate research trends in this field. METHODS: According to the Web of Science database, articles with more than 400 citations qualify as "citation classics". We conducted a literature search on the ISI Web of Science bibliometric database for scientific articles relevant to epilepsy. RESULTS: We retrieved 67 highly cited articles (400 or more citations, which were published in 31 journals: 17 clinical studies, 42 laboratory studies, 5 reviews and 3 classification articles. Clinical studies consisted of epidemiological analyses (n=3, studies on the clinical phenomenology of epilepsy (n=5 – including behavioral and prognostic aspects – and articles focusing on pharmacological (n=6 and non-pharmacological (n=3 treatment. The laboratory studies dealt with genetics (n=6, animal models (n=27, and neurobiology (n=9 – including both neurophysiology and neuropathology studies. The majority (61% of citation classics on epilepsy were published after 1986, possibly reflecting the expansion of research interest in laboratory studies driven by the development of new methodologies, specifically in the fields of genetics and animal models. Consequently, clinical studies were highly cited both before and after the mid 80s, whilst laboratory researches became widely cited after 1990. CONCLUSIONS: Our study indicates that the main drivers of scientific impact in the field of epileptology have increasingly become genetic and neurobiological studies, along with research on animal models of epilepsy. These articles are able to gain the highest numbers of citations in the time span of a few years and suggest potential directions for future research.

  3. Reactions to ingroup and outgroup deviants: an experimental group paradigm for black sheep effect.

    Directory of Open Access Journals (Sweden)

    Marika Rullo

    Full Text Available In the classic black sheep effect (BSE an ingroup deviant member is usually evaluated more negatively than the corresponding outgroup deviant. This effect is usually obtained by using scenarios and asking people to imagine the situation as vividly as possible. The present study proposes a new method to investigate the BSE by considering the behavioral and physiological reactions to unfair behavior (aggressive game behavior in a realistic experimental group-setting. The study involved 52 university students in a minimal group setting who performed a modified version of the competitive reaction time (CRT task adapted to be played in groups of four people. The classic BSE was replicated for evaluation but not for the behavioral reactions (retaliate to aggression to deviants. More interestingly, a negative relationship emerged in the ingroup deviant condition between the level of behavioral derogation and the systolic blood pressure level.

  4. Economic evaluation of genomic selection in small ruminants: a sheep meat breeding program.

    Science.gov (United States)

    Shumbusho, F; Raoul, J; Astruc, J M; Palhiere, I; Lemarié, S; Fugeray-Scarbel, A; Elsen, J M

    2016-06-01

    Recent genomic evaluation studies using real data and predicting genetic gain by modeling breeding programs have reported moderate expected benefits from the replacement of classic selection schemes by genomic selection (GS) in small ruminants. The objectives of this study were to compare the cost, monetary genetic gain and economic efficiency of classic selection and GS schemes in the meat sheep industry. Deterministic methods were used to model selection based on multi-trait indices from a sheep meat breeding program. Decisional variables related to male selection candidates and progeny testing were optimized to maximize the annual monetary genetic gain (AMGG), that is, a weighted sum of meat and maternal traits annual genetic gains. For GS, a reference population of 2000 individuals was assumed and genomic information was available for evaluation of male candidates only. In the classic selection scheme, males breeding values were estimated from own and offspring phenotypes. In GS, different scenarios were considered, differing by the information used to select males (genomic only, genomic+own performance, genomic+offspring phenotypes). The results showed that all GS scenarios were associated with higher total variable costs than classic selection (if the cost of genotyping was 123 euros/animal). In terms of AMGG and economic returns, GS scenarios were found to be superior to classic selection only if genomic information was combined with their own meat phenotypes (GS-Pheno) or with their progeny test information. The predicted economic efficiency, defined as returns (proportional to number of expressions of AMGG in the nucleus and commercial flocks) minus total variable costs, showed that the best GS scenario (GS-Pheno) was up to 15% more efficient than classic selection. For all selection scenarios, optimization increased the overall AMGG, returns and economic efficiency. As a conclusion, our study shows that some forms of GS strategies are more advantageous

  5. THE USE OF MICROSATELLITE MARKERS TO STUDY GENETIC DIVERSITY IN INDONESIAN SHEEP

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    Jakaria

    2012-03-01

    Full Text Available The purpose of this research was to study genetic diversity in Indonesian sheep population using microsatellite markers. A total of 18 microsatellite loci have been used for genotyping Indonesian sheep. Total sheep blood 200 samples were extracted from garut sheep of fighting and meat types, purbalingga sheep, batur sheep and jember sheep populations by using a salting out method. Microsatellite loci data were analyzed using POPGENE 3.2 software. Based on this study obtained 180 alleles from 17 microsatellite loci, while average number of alleles was 6.10 alleles (6 to 18 alleles from five Indonesian sheep populations (garut sheep of fighting type, garut sheep of meat type, purbalingga sheep, batur sheep and jember sheep population. The average of observed heterozygosity (Ho and expected heterozygosity (He values were 0.5749 and 0.6896, respectively, while the genetic differentiation for inbreeding among population (FIS, within population (FIT and average genetic differentiation (FST were 0.1006, 0.1647 and 0.0712, respectively. Genetic distance and genetic tree showed that Indonesian sheep population was distinct from garut sheep of fighting and meat types, purbalingga sheep, batur sheep and jember sheep population. Based on this results were needed a strategy for conservation and breeding programs in each Indonesian sheep population.

  6. Sheep models of polycystic ovary syndrome phenotype.

    Science.gov (United States)

    Padmanabhan, Vasantha; Veiga-Lopez, Almudena

    2013-07-01

    Polycystic ovary syndrome (PCOS) is a fertility disorder affecting 5-7% of reproductive-aged women. Women with PCOS manifest both reproductive and metabolic defects. Several animal models have evolved, which implicate excess steroid exposure during fetal life in the development of the PCOS phenotype. This review addresses the fetal and adult reproductive and metabolic consequences of prenatal steroid excess in sheep and the translational relevance of these findings to PCOS. By comparing findings in various breeds of sheep, the review targets the role of genetic susceptibility to fetal insults. Disruptions induced by prenatal testosterone excess are evident at both the reproductive and metabolic level with each influencing the other thus creating a self-perpetuating vicious cycle. The review highlights the need for identifying a common mediator of the dysfunctions at the reproductive and metabolic levels and developing prevention and treatment interventions targeting all sites of disruption in unison for achieving optimal success.

  7. Experimental studies of chronic pneumonia of sheep.

    Science.gov (United States)

    Gilmour, J S; Jones, G E; Rae, A G

    1979-01-01

    Strains of Mycoplasma ovipneumoniae and Pasteurella haemolytica isolated from sheep affected with chronic pneumonia were inoculated by endobronchial route to conventionally-reared and SPF (Specific Pathogen-Free) lambs. Changes resembling those of the naturally-occurring disease were produced in most lambs given the organisms in combination and in some given M. ovipneumoniae alone. Similar but less extensive changes were seen in SPF lambs and fewer animals were affected. Different strains of M. ovipneumoniae did not affect the extent of changes produced in SPF lambs. M. ovipneumoniae became established in the lungs of both types of sheep; P. haemolytica did so less readily. It was concluded that chronic pneumonia may be reproduced in conventional animals by combined inoculation of M. ovipneumoniae and P. haemolytica. Age and status of immunity to mycoplasmas may account for the different responses of conventional and SPF lambs.

  8. Mastitis detection in sheep by infrared thermography.

    Science.gov (United States)

    Martins, Rafhael Felipe Saraiva; do Prado Paim, Tiago; de Abreu Cardoso, Cyntia; Stéfano Lima Dallago, Bruno; de Melo, Cristiano Barros; Louvandini, Helder; McManus, Concepta

    2013-06-01

    This study aims to evaluate the use of an infrared thermograph for mastitis diagnosis in sheep. Thirty-seven Santa Inês ewes were evaluated weekly through infrared images obtained with thermograph FLIR System Series-i®. Milk was collected for somatic cell count and milk compound level determination. The clinical mastitis group had the highest fat and protein level, as well as the lowest lactose level. The udder temperatures were higher for subclinical mastitis group. The udder temperature data was able to correctly classify the animals into the mastitis groups and the canonical analysis showed that these temperatures clearly differentiated the subclinical mastitis groups from the others. Therefore, this study showed that udder infrared temperatures can be used as diagnostic method to mastitis in sheep. PMID:23178047

  9. Sheep internal parasites on Rab and Pag

    Directory of Open Access Journals (Sweden)

    Relja Beck

    2010-01-01

    Full Text Available The purpose of our research was to determine which groups and species of internal parasites endanger the health of sheep on the islands of Rab and Pag. The research was carried out in 10 flocks on both islands taking the fresh dung out of 30% of the total number of sheep in each flock. It was ascertained that the gastrointestinal parasites and protozoa of Eimeria genus are present in most flocks on both islands. The presence of the fluke Dicrocoelium dendriticum was ascertained in considerably larger number of flocks on the island of Rab than on the island of Pag. On the other hand, the presence of parasites of Moniezia and Nematodirus genus was ascertained in larger number of flocks on the island of Pag. In two flocks on Rab parasites of Protostrongylus genus were ascertained while on the island of Pag they were not found in any flock.

  10. Doenças de ovinos diagnosticadas no Laboratório de Anatomia Patológica Animal da Universidade Federal de Mato Grosso do Sul (1996-2010 Sheep diseases diagnosed at the Laboratory of Animal Pathology, Federal University of Mato Grosso do Sul, Brazil (1996-2010

    Directory of Open Access Journals (Sweden)

    Thiago L. Almeida

    2013-01-01

    Full Text Available Nas últimas décadas a pecuária ovina cresceu significativamente no Brasil. Concomitantemente, grupos de pesquisas e laboratórios de diagnósticos realizam estudos retrospectivos com a finalidade de fornecer subsídios técnico-científicos para os médicos veterinários. Desta forma, realizou-se um estudo de prevalência nos arquivos do Laboratório de Anatomia Patológica Animal (LAP da Universidade Federal de Mato Grosso do Sul (UFMS no período de Janeiro de 1996 a Dezembro de 2010. O Laboratório de Bacteriologia da UFMS e o Setor de Patologia Veterinária da Universidade Federal do Rio Grande do Sul forneceram apoio diagnóstico nos casos de mannheimiose pulmonar e scrapie, respectivamente. Os laudos da espécie ovina foram revisados e agrupados em conclusivos e inconclusivos, dos quais foram excluídos os casos experimentais e de outros estados e países. Os casos conclusivos foram classificados de acordo com a etiologia da doença. Os exames da espécie ovina somaram 331 laudos (3,97 % de um total de 8.333 casos diagnosticados no período. Destes, foram excluídos sessenta e quatro (19,3% casos experimentais e materiais oriundos de outros estados ou países. Dos 267 casos remanescentes, 87 (32,6% foram inconclusivos e 180 (67,4% considerados conclusivos, sendo 60 (33,3% doenças infecciosas e parasitárias; 45 (25% intoxicações e toxi-infecções; 41 (22,8% "lesões sem causa definida"; 22 (12,2% doenças metabólicas e nutricionais; 10 (5,6% foram classificadas como "outros distúrbios" e 2 (1,1% neoplasmas. A hemoncose, intoxicação por Brachiaria spp., pleuropneumonias, broncopneumonias, pneumonias fibrinonecrosante ou fibrinossupurativa sem causa definida e a intoxicação por cobre foram as doenças mais prevalentes no período estudado. Dois casos de scrapie foram diagnosticados no período.Sheep farming has increased significantly in Brazil during the last decades. Concurrently, research groups and diagnostic laboratories

  11. Paternal inheritance of mitochondrial DNA in the sheep (Ovine aries)

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Paternal inheritance of mitochondria DNA in sheep was discovered by examination of 152 sheep from 38 hybrid families for mtDNA D-loop polymorphisms using PCR-RFLP, amplification of repeated sequence somain, and PCR-SSCP of the D-loop 5′ end region of a 253 bp fragment. Our findings have provided the first evidence of paternal inheritance of mtDNA in sheep and possible mechanisms of paternal inheritance were discussed.

  12. Research Progress on Technique of Frozen Embryo Transfer in Sheep

    Institute of Scientific and Technical Information of China (English)

    SHE Qiu-sheng; HU Jian-ye; LOU Peng-yan; TAO Jing; XIE Zhao-hui

    2011-01-01

    The paper introduced the research progress on the technique of frozen embryo transfer in sheep, illustrated selection of donors and receptors, superovulation, synchronization of estrus, embryo cryopreservation and embryo transplantation. Frozen embryo transfer in sheep is another breakthrough in the high-quality sheep raising, and this technique in China is in its infancy recommendation stage, but it will be comprehensively popularized in the future.

  13. MEAT PRODUCTIVITY OF CROSSBRED SHEEP CALVES

    OpenAIRE

    Degtyar A. S.; Kolosov A. Y.; Romanets T. S.

    2015-01-01

    The article presents the results of the control slaughter of purebred and crossbred lambs. It was found that the index of compactness and the main killer performance superiority had two or three breed lambs obtained from crosses involving sheep southern meat breed. The experimental animals were taken measurements of carcasses, which give a fairly complete and objective view of the differences in the length of the torso, hips, mascara and hip girth. There are specific differences in the yield ...

  14. Sheep models of polycystic ovary syndrome phenotype

    OpenAIRE

    Padmanabhan, Vasantha; Veiga-Lopez, Almudena

    2012-01-01

    Polycystic ovary syndrome (PCOS) is a fertility disorder affecting 5–7% of reproductive-aged women. Women with PCOS manifest both reproductive and metabolic defects. Several animal models have evolved, which implicate excess steroid exposure during fetal life in the development of the PCOS phenotype. This review addresses the fetal and adult reproductive and metabolic consequences of prenatal steroid excess in sheep and the translational relevance of these findings to PCOS. By comparing findi...

  15. Classical Fourier analysis

    CERN Document Server

    Grafakos, Loukas

    2014-01-01

    The main goal of this text is to present the theoretical foundation of the field of Fourier analysis on Euclidean spaces. It covers classical topics such as interpolation, Fourier series, the Fourier transform, maximal functions, singular integrals, and Littlewood–Paley theory. The primary readership is intended to be graduate students in mathematics with the prerequisite including satisfactory completion of courses in real and complex variables. The coverage of topics and exposition style are designed to leave no gaps in understanding and stimulate further study. This third edition includes new Sections 3.5, 4.4, 4.5 as well as a new chapter on “Weighted Inequalities,” which has been moved from GTM 250, 2nd Edition. Appendices I and B.9 are also new to this edition.  Countless corrections and improvements have been made to the material from the second edition. Additions and improvements include: more examples and applications, new and more relevant hints for the existing exercises, new exercises, and...

  16. The Classical Electron Problem

    CERN Document Server

    Gill, T L; Lindesay, J

    2001-01-01

    In this paper, we construct a parallel image of the conventional Maxwell theory by replacing the observer-time by the proper-time of the source. This formulation is mathematically, but not physically, equivalent to the conventional form. The change induces a new symmetry group which is distinct from, but closely related to the Lorentz group, and fixes the clock of the source for all observers. The new wave equation contains an additional term (dissipative), which arises instantaneously with acceleration. This shows that the origin of radiation reaction is not the action of a "charge" on itself but arises from inertial resistance to changes in motion. This dissipative term is equivalent to an effective mass so that classical radiation has both a massless and a massive part. Hence, at the local level the theory is one of particles and fields but there is no self-energy divergence (nor any of the other problems). We also show that, for any closed system of particles, there is a global inertial frame and unique (...

  17. Time, classical and quantum

    Science.gov (United States)

    Aniello, P.; Ciaglia, F. M.; Di Cosmo, F.; Marmo, G.; Pérez-Pardo, J. M.

    2016-10-01

    We propose a new point of view regarding the problem of time in quantum mechanics, based on the idea of replacing the usual time operator T with a suitable real-valued function T on the space of physical states. The proper characterization of the function T relies on a particular relation with the dynamical evolution of the system rather than with the infinitesimal generator of the dynamics (Hamiltonian). We first consider the case of classical hamiltonian mechanics, where observables are functions on phase space and the tools of differential geometry can be applied. The idea is then extended to the case of the unitary evolution of pure states of finite-level quantum systems by means of the geometric formulation of quantum mechanics. It is found that T is a function on the space of pure states which is not associated with any self-adjoint operator. The link between T and the dynamical evolution is interpreted as defining a simultaneity relation for the states of the system with respect to the dynamical evolution itself. It turns out that different dynamical evolutions lead to different notions of simultaneity, i.e., the notion of simultaneity is a dynamical notion.

  18. Classics in radio astronomy

    CERN Document Server

    Sullivan, Woodruff Turner

    1982-01-01

    Radio techniques were the nrst to lead astronomy away from the quiescent and limited Universe revealed by traditional observations at optical wave­ lengths. In the earliest days of radio astronomy, a handful of radio physicists and engineers made one startling discovery after another as they opened up the radio sky. With this collection of classic papers and the extensive intro­ ductory material, the reader can experience these exciting discoveries, as well as understand the developing techniques and follow the motivations which prompted the various lines of inquiry. For instance he or she will follow in detail the several attempts to detect radio waves from the sun at the turn of the century; the unravelling by Jansky of a "steady hiss type static"; the incredible story of Reber who built a 9 meter dish in his backyard in 1937 and then mapped the Milky Way; the vital discoveries by Hey and colleagues of radio bursts from the Sun and of a discrete source in the constellation of Cygnus; the development of re...

  19. Extended symmetrical classical electrodynamics.

    Science.gov (United States)

    Fedorov, A V; Kalashnikov, E G

    2008-03-01

    In this paper, we discuss a modification of classical electrodynamics in which "ordinary" point charges are absent. The modified equations contain additional terms describing the induced charges and currents. The densities of the induced charges and currents depend on the vector k and the vectors of the electromagnetic field, E and B . It is shown that the vectors E and B can be defined in terms of two four-potentials and the components of k are the components of a four-tensor of the third rank. The Lagrangian of the modified electrodynamics is defined. The conditions are derived at which only one four-potential determines the behavior of the electromagnetic field. It is also shown that static modified electrodynamics can describe the electromagnetic field in the inner region of an electric monopole. In the outer region of the electric monopole the electric field is governed by the Maxwell equations. It follows from boundary conditions at the interface between the inner and outer regions of the monopole that the vector k has a discrete spectrum. The electric and magnetic fields, energy, and angular momentum of the monopole are found for different eigenvalues of k .

  20. Classical competing risks

    CERN Document Server

    Crowder, Martin J

    2001-01-01

    If something can fail, it can often fail in one of several ways and sometimes in more than one way at a time. There is always some cause of failure, and almost always, more than one possible cause. In one sense, then, survival analysis is a lost cause. The methods of Competing Risks have often been neglected in the survival analysis literature. Written by a leading statistician, Classical Competing Risks thoroughly examines the probability framework and statistical analysis of data of Competing Risks. The author explores both the theory of the subject and the practicalities of fitting the models to data. In a coherent, self-contained, and sequential account, the treatment moves from the bare bones of the Competing Risks setup and the associated likelihood functions through survival analysis using hazard functions. It examines discrete failure times and the difficulties of identifiability, and concludes with an introduction to the counting-process approach and the associated martingale theory.With a dearth of ...

  1. Royana: Successful Experience in Cloning the Sheep

    Directory of Open Access Journals (Sweden)

    Saeed Kazemi Ashtiani

    2008-01-01

    Full Text Available Objective: This study describes our experiences in reproductive cloning using two differentprocedures resulting in birth of the first successfully cloned sheep in Iran and theMiddle-East, nick-named "Royana".Materials and Methods: Abattoir-derived sheep oocytes were enucleated after in vitromaturation for 18-20hrs and then reconstructed by ear-derived sheep somatic cells usingtwo different procedures of renucleation (subzonary, intracytoplasmic, embryo culture (coculture,sequential medium and embryo transfer (intra fallopian, intra uterine. Pregnancystatus and fetal development were followed regularly and elective cesarean was inductedon day 145 of pregnancy. Histopathological and genetical examinations were performedon either aborted and delivered clones for confirmation different aspects of cloning.Results: The two procedures were both efficient in producing early and/or advancedcloned embryos, establishing early and/or advanced stages of pregnancy till delivery. Fourpregnancies were detected; one were failed at early pregnancy, one aborted on day 90,one was still born and the fourth delivered to a healthy male lamb nick named "Royana".Conclusion: Many different approaches have been developed for mammalian cloningwhich all are judged by their ultimate potency for establishment of successful pregnanciesterminated to healthy/viable clones. As a preliminary study toward establishment ofthe technology, this study also successfully examined the competency of two proceduresof somatic cell nuclear transfer (SCNT. However, the overall low efficiency of SCNT indicatesthat many different aspects of the technology remain to be dissolved.

  2. Classical and quantum effective theories

    CERN Document Server

    Polonyi, Janos

    2014-01-01

    A generalization of the action principle of classical mechanics, motivated by the Closed Time Path (CTP) scheme of quantum field theory, is presented to deal with initial condition problems and dissipative forces. The similarities of the classical and the quantum cases are underlined. In particular, effective interactions which describe classical dissipative forces represent the system-environment entanglement. The relation between the traditional effective theories and their CTP extension is briefly discussed and few qualitative examples are mentioned.

  3. Population in the classic economics

    OpenAIRE

    Adnan Doğruyol

    2013-01-01

    Growth subject in economics is an important factor of development. Classic economics ecole indicates the population as main variable which tender of growth. On the other hand T. R. Malthus is known as economist who regards population as a problem and brings up it among the classical economists. However, Adam Smith is an intellectual who discussed population problem earlier on the classic economics theory. According to Adam Smith one of the main factors that realise the growth is labour. In ad...

  4. The classic: Bone morphogenetic protein.

    Science.gov (United States)

    Urist, Marshall R; Strates, Basil S

    2009-12-01

    This Classic Article is a reprint of the original work by Marshall R. Urist and Basil S. Strates, Bone Morphogenetic Protein. An accompanying biographical sketch of Marshall R. Urist, MD is available at DOI 10.1007/s11999-009-1067-4; a second Classic Article is available at DOI 10.1007/s11999-009-1069-2; and a third Classic Article is available at DOI 10.1007/s11999-009-1070-9. The Classic Article is copyright 1971 by Sage Publications Inc. Journals and is reprinted with permission from Urist MR, Strates BS. Bone morphogenetic protein. J Dent Res. 1971;50:1392-1406.

  5. The classic: Bone morphogenetic protein.

    Science.gov (United States)

    Urist, Marshall R; Strates, Basil S

    2009-12-01

    This Classic Article is a reprint of the original work by Marshall R. Urist and Basil S. Strates, Bone Morphogenetic Protein. An accompanying biographical sketch of Marshall R. Urist, MD is available at DOI 10.1007/s11999-009-1067-4; a second Classic Article is available at DOI 10.1007/s11999-009-1069-2; and a third Classic Article is available at DOI 10.1007/s11999-009-1070-9. The Classic Article is copyright 1971 by Sage Publications Inc. Journals and is reprinted with permission from Urist MR, Strates BS. Bone morphogenetic protein. J Dent Res. 1971;50:1392-1406. PMID:19727989

  6. Studies on Phylogenetic Relationship of Sheep Population in East and South of Central Asia

    Institute of Scientific and Technical Information of China (English)

    SUN Wei; CHANG Hong; YANG Zhang-ping; GENG Rong-qing; LU Sheng-xia; DU Lei; NI Da-xing; FAN Bao-sheng; Tsunoda K

    2002-01-01

    This paper was based on the Hu sheep in China, after collecting the same data about 9 Asiasheep populations and 5 European sheep (breeds in Japan) populations. It clustered 15 populations in terms ofthe gene frequency of 10 loci and 33 allele in blood enzyme and other protein variations. The result of Hierar-chy Clustering showed that the sheep populations in the East and South of Central Asia could be classified intothree genetic groups: Mongolia sheep, South Asia sheep and European sheep, and the Hu sheep belonged toMongolia sheep.

  7. Investigation of transferrin polymorphism in Garole sheep.

    Science.gov (United States)

    Yadav, Devesh K; Taraphder, Subhash; Sahoo, Ajit K; Dhara, K C

    2010-03-01

    The aim of this study was to determine the genetics of polymorph systems of Transferrin in Garole sheep breed. The present study was conducted on 95 adult Garole sheep comprising 52 ewes and 43 rams, maintained at Sheep and Goat Breeding Farm of West Bengal University of Animal and Fishery Sciences, West Bengal, during the period from April-September, 2009. The polymorphism of transferrin was determined through SDS-Polyacrylamide gel electrophoresis technique. It was found that the transferrin type was controlled by five codominant alleles (TfA, TfB, TfC TfD and TfE) in Garole sheep. These five alleles, because of co-dominant nature of inheritance, determined the occurrence of nine transferrin genotypes in the analyzed flock. Four (TfAA, TfBB, TfCC and TfDD) of these were homozygous and the remaining five (TfAD, TfBC, TfBD, TfCD and TfDE) heterozygous. It was found that the TfDD genotype (0.263) was predominant while TfDE genotype (0.042) was least common in the analyzed flock. Frequencies of other genotypes were as: TfCD(0.242), TfBD(0.126), TfCC(0.084), TfBB(0.074), TfAA(0.063), TfAD and TfBC (0.053 for each genotype ) in whole population. From the result it was found that in whole population combined, the heterozygotic genotypic frequency (0.516) was more than that of homozygotic genotypic frequency (0.484). Considerable variations were recognized in the frequencies of transferrin alleles. In the whole population frequencies of transferrin alleles were found to be TfA = 0.089, TfB = 0.163, TfC = 0.232, TfD = 0.495 and TfE = 0.021. Transferrin system has shown an absence of genetic equilibrium among the analyzed herd (chi2 value = 51.31). In conclusion, there were polymorphism in Transferrin types and the presence of differences among the frequencies of the five alleles by categories could be a source of genetic variation in Garole sheep. PMID:20349135

  8. A Classic Beauty

    Science.gov (United States)

    2007-01-01

    M51, whose name comes from being the 51st entry in Charles Messier's catalog, is considered to be one of the classic examples of a spiral galaxy. At a distance of about 30 million light-years from Earth, it is also one of the brightest spirals in the night sky. A composite image of M51, also known as the Whirlpool Galaxy, shows the majesty of its structure in a dramatic new way through several of NASA's orbiting observatories. X-ray data from NASA's Chandra X-ray Observatory reveals point-like sources (purple) that are black holes and neutron stars in binary star systems. Chandra also detects a diffuse glow of hot gas that permeates the space between the stars. Optical data from the Hubble Space Telescope (green) and infrared emission from the Spitzer Space Telescope (red) both highlight long lanes in the spiral arms that consist of stars and gas laced with dust. A view of M51 with the Galaxy Evolution Explorer telescope shows hot, young stars that produce lots of ultraviolet energy (blue). The textbook spiral structure is thought be the result of an interaction M51 is experiencing with its close galactic neighbor, NGC 5195, which is seen just above. Some simulations suggest M51's sharp spiral shape was partially caused when NGC 5195 passed through its main disk about 500 million years ago. This gravitational tug of war may also have triggered an increased level of star formation in M51. The companion galaxy's pull would be inducing extra starbirth by compressing gas, jump-starting the process by which stars form.

  9. Innovation: the classic traps.

    Science.gov (United States)

    Kanter, Rosabeth Moss

    2006-11-01

    Never a fad, but always in or out of fashion, innovation gets rediscovered as a growth enabler every half dozen years. Too often, though, grand declarations about innovation are followed by mediocre execution that produces anemic results, and innovation groups are quietly disbanded in cost-cutting drives. Each managerial generation embarks on the same enthusiastic quest for the next new thing. And each generation faces the same vexing challenges- most of which stem from the tensions between protecting existing revenue streams critical to current success and supporting new concepts that may be crucial to future success. In this article, Harvard Business School professor Rosabeth Moss Kanter reflects on the four major waves of innovation enthusiasm she's observed over the past 25 years. She describes the classic mistakes companies make in innovation strategy, process, structure, and skills assessment, illustrating her points with a plethora of real-world examples--including AT&T Worldnet, Timberland, and Ocean Spray. A typical strategic blunder is when managers set their hurdles too high or limit the scope of their innovation efforts. Quaker Oats, for instance, was so busy in the 1990s making minor tweaks to its product formulas that it missed larger opportunities in distribution. A common process mistake is when managers strangle innovation efforts with the same rigid planning, budgeting, and reviewing approaches they use in their existing businesses--thereby discouraging people from adapting as circumstances warrant. Companies must be careful how they structure fledgling entities alongside existing ones, Kanter says, to avoid a clash of cultures and agendas--which Arrow Electronics experienced in its attempts to create an online venture. Finally, companies commonly undervalue and underinvest in the human side of innovation--for instance, promoting individuals out of innovation teams long before their efforts can pay off. Kanter offers practical advice for avoiding

  10. Utilização de biópsias da terceira pálpebra e mucosa retal em ovinos para diagnóstico de scrapie em uma propriedade da região sul do Brasil

    Directory of Open Access Journals (Sweden)

    Juliano S. Leal

    2012-10-01

    Full Text Available Scrapie é uma encefalopatia espongiforme transmissível (EET que causa lesões cerebrais degenerativas em ovinos e caprinos. Caracteriza-se pelo acúmulo, no tecido encefálico e linforreticular, da forma anormal da proteína priônica (PrP Sc que provoca a morte maciça de neurônios e células gliais, além de vacuolização intensa no tecido afetado. Esse trabalho descreve a utilização da técnica de imuno-histoquímica (IHQ para proteína priônica em tecido linforreticular de biópsias de terceira pálpebra e mucosa retal, como método diagnóstico de scrapie em ovinos. Realizaram-se exames de IHQ para scrapie em amostras de uma propriedade de origem de um ovino com diagnóstico dessa enfermidade. Utilizaram-se anticorpos monoclonais antipríon para diagnóstico ante mortem pela técnica de IHQ. Nas 318 amostras de biópsias analisadas, encontrou-se 19 resultados positivos para PrP Sc nos folículos de terceira pálpebra e não foi obtida marcação no tecido linfático de mucosa retal em nenhuma das amostras coletadas. Realizaram-se 18 necropsias dos animais positivos anteriormente por biópsia e 21 necropsias de ovinos parentes dos positivos de scrapie. Confirmou-se o resultado de scrapie pela IHQ após a necropsia dos animais positivos nas biópsias de terceira pálpebra. Nesses animais, os órgãos com maior número de cortes positivos foram a terceira pálpebra (18/18 e a tonsila (8/18. Nos ovinos com parentesco com os positivos, nenhum resultado de scrapie ocorreu. A utilização de tecidos linfoides no diagnóstico de scrapie por IHQ através de biópsias mostrou-se um método viável e eficaz para o diagnóstico pré-clínico.

  11. Quantitative trait loci for resistance to trichostrongylid infection in Spanish Churra sheep

    Directory of Open Access Journals (Sweden)

    Primitivo Fermin San

    2009-10-01

    Full Text Available Abstract Background For ruminants reared on grazing systems, gastrointestinal nematode (GIN parasite infections represent the class of diseases with the greatest impact on animal health and productivity. Among the many possible strategies for controlling GIN infection, the enhancement of host resistance through the selection of resistant animals has been suggested by many authors. Because of the difficulty of routinely collecting phenotypic indicators of parasite resistance, information derived from molecular markers may be used to improve the efficiency of classical genetic breeding. Methods A total of 181 microsatellite markers evenly distributed along the 26 sheep autosomes were used in a genome scan analysis performed in a commercial population of Spanish Churra sheep to detect chromosomal regions associated with parasite resistance. Following a daughter design, we analysed 322 ewes distributed in eight half-sib families. The phenotypes studied included two faecal egg counts (LFEC0 and LFEC1, anti-Teladorsagia circumcincta LIV IgA levels (IgA and serum pepsinogen levels (Peps. Results The regression analysis revealed one QTL at the 5% genome-wise significance level on chromosome 6 for LFEC1 within the marker interval BM4621-CSN3. This QTL was found to be segregating in three out of the eight families analysed. Four other QTL were identified at the 5% chromosome-wise level on chromosomes 1, 10 and 14. Three of these QTL influenced faecal egg count, and the other one had an effect on IgA levels. Conclusion This study has successfully identified segregating QTL for parasite resistance traits in a commercial population. For some of the QTL detected, we have identified interesting coincidences with QTL previously reported in sheep, although most of those studies have been focused on young animals. Some of these coincidences might indicate that some common underlying loci affect parasite resistance traits in different sheep breeds. The

  12. Classic writings on instructional technology

    NARCIS (Netherlands)

    Ely, Donald P.; Plomp, Tjeerd

    1996-01-01

    This paper describes the selection process of 17 articles for inclusion in the book, "Classic Writings on Instructional Technology." The book brings together original "classic" educational technology articles into one volume to document the history of the field through its literature. It is also an

  13. Dynamical Symmetries in Classical Mechanics

    Science.gov (United States)

    Boozer, A. D.

    2012-01-01

    We show how symmetries of a classical dynamical system can be described in terms of operators that act on the state space for the system. We illustrate our results by considering a number of possible symmetries that a classical dynamical system might have, and for each symmetry we give examples of dynamical systems that do and do not possess that…

  14. Teaching and Demonstrating Classical Conditioning.

    Science.gov (United States)

    Sparrow, John; Fernald, Peter

    1989-01-01

    Discusses classroom demonstrations of classical conditioning and notes tendencies to misrepresent Pavlov's procedures. Describes the design and construction of the conditioner that is used for demonstrating classical conditioning. Relates how students experience conditioning, generalization, extinction, discrimination, and spontaneous recovery.…

  15. Classical Music Fan Chen Li

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The heyday of Beijing’s classical music beganin 1993, when top-quality sound equipment andrecords were imported. Also in that year, BeijingMusic Radio presented a classical music programtitled "Fan’s Club" and founded the "Music and

  16. Classic African American Children's Literature

    Science.gov (United States)

    McNair, Jonda C.

    2010-01-01

    The purpose of this article is to assert that there are classic African American children's books and to identify a sampling of them. The author presents multiple definitions of the term classic based on the responses of children's literature experts and relevant scholarship. Next, the manner in which data were collected and analyzed in regard to…

  17. Classical dynamics a modern perspective

    CERN Document Server

    Sudarshan, Ennackal Chandy George

    2016-01-01

    Classical dynamics is traditionally treated as an early stage in the development of physics, a stage that has long been superseded by more ambitious theories. Here, in this book, classical dynamics is treated as a subject on its own as well as a research frontier. Incorporating insights gained over the past several decades, the essential principles of classical dynamics are presented, while demonstrating that a number of key results originally considered only in the context of quantum theory and particle physics, have their foundations in classical dynamics.Graduate students in physics and practicing physicists will welcome the present approach to classical dynamics that encompasses systems of particles, free and interacting fields, and coupled systems. Lie groups and Lie algebras are incorporated at a basic level and are used in describing space-time symmetry groups. There is an extensive discussion on constrained systems, Dirac brackets and their geometrical interpretation. The Lie-algebraic description of ...

  18. Aberrant ERK 1/2 complex activation and localization in scrapie-infected GT1-1 cells

    Directory of Open Access Journals (Sweden)

    Didonna Alessandro

    2010-08-01

    Full Text Available Abstract Background Fatal neurodegenerative disorders such as Creutzfeldt-Jakob and Gerstmann-Sträussler-Scheinker diseases in humans, scrapie and bovine spongiform encephalopathy in animals, are characterized by the accumulation in the brain of a pathological form of the prion protein (PrP denominated PrPSc. The latter derives from the host cellular form, PrPC, through a process whereby portions of its α-helical and coil structures are refolded into β-sheet structures. Results In this work, the widely known in vitro model of prion replication, hypothalamic GT1-1 cell line, was used to investigate cellular and molecular responses to prion infection. The MAP kinase cascade was dissected to assess the phosphorylation levels of src, MEK 1/2 and ERK 1/2 signaling molecules, both before and after prion infection. Our findings suggest that prion replication leads to a hyper-activation of this pathway. Biochemical analysis was complemented with immunofluorescence studies to map the localization of the ERK complex within the different cellular compartments. We showed how the ERK complex relocates in the cytosol upon prion infection. We correlated these findings with an impairment of cell growth in prion-infected GT1-1 cells as probed by MTT assay. Furthermore, given the persistent urgency in finding compounds able to cure prion infected cells, we tested the effects on the ERK cascade of two molecules known to block prion replication in vitro, quinacrine and Fab D18. We were able to show that while these two compounds possess similar effects in curing prion infection, they affect the MAP kinase cascade differently. Conclusions Taken together, our results help shed light on the molecular events involved in neurodegeneration and neuronal loss in prion infection and replication. In particular, the combination of chronic activation and aberrant localization of the ERK complex may lead to a lack of essential neuroprotective and survival factors

  19. Comparison Study on Clinical and Neuropathological Characteristics of Hamsters Inoculated With Scrapie Strain 263K in Different Challenging Pathways

    Institute of Scientific and Technical Information of China (English)

    JIN ZHANG; XIAO-BO ZHOU; GUI-PING MA; YONG LIU; CAI-MIN XU; XIAO-PING DONG; LAN CHEN; BAO-YUN ZHAN; JUN HAN; XIN-LI XIAO; HAI-YAN TIAN; BIN-LING LI; CHEN GAO; JIAN-MEI GAO

    2004-01-01

    Objective To understand the infectious characteristics of a hamster-adapted scrapie strain 263K with five different routes of infection including intracerebral (i.c.), intraperitoneal (i.p.),intragastrical (i.g.), intracardiac and intramuscular (i. m.) approaches. Methods Hamsters were infected with crude- or fine-prepared brain extracts. The neuropathological changes, PrPSc deposits,and patterns of PK-resistant PrP were analyzed by HE stain, immunohistochemistry (IHC) assay and Western blot. Reactive gliosis and neuron loss were evaluated by glial fibrillary acidic protein (GFAP)and neuron specific enolase (NSE) specific IHC. Results The animals inoculated in i.m. and i.p.ways with crude PrPSc extracts showed clinical signs at the average incubation of 69.2+-2.8 and 65.5±3.9 days. Inoculation in i.c. and intracardiac ways with fine PrPSc extracts (0.00035 g) caused similar,but relative long incubation of around 90 days. Only oneout of eight hamsters challenged ini.g way with low dosage (0.01 g) became ill after a much longer incubation (185 d), while all animals (4/4)with high dosage (0.04 g) developed clinical signs 105 days postinfection. The most remarkable spongiform degeneration and PrPsc deposits were found in brain stem among the five challenge groups generally. The number of GFAP-positive astrocytes increased distinctly in brain stems in all infection groups, while the number of NSE-positive cells decreased significantly in cerebrum, except i.c. group. The patterns of PK-resistant PrP in brains were basically identical among the five infection routes. Conclusion Typical TSE could be induced in hamsters by inoculating strain 263K in the five infection ways. The incubation periods in bioassays depend on infective dosage, administrating pathway and preparation of PrPSc. The neuropathological changes and PrPSc deposits seem to be related with regions and inoculating pathways.

  20. Characterization of introduced breed of sheep and pattenl of conservation of Sumatera thin tail (STT sheep in North Sumatera

    Directory of Open Access Journals (Sweden)

    Priyanto D

    2000-03-01

    Full Text Available Sumatera thin tail (STT sheep are highly adapted to the local environment, no seasonal reproductive activity, and highresistance to internal parasite, but they have small body size and low mature body weight. "On Fann research" to identify morphological characteristics of intoduced breed and STT sheep, as well as an altemative conservation pattem were conducted in two location, i.e. Pulahan village, Air Batu District, Asahan Regency as the potensial area for STT sheep and Pulo Gambar village, Galang District, Deli Serdang Regency as the development area of introduced breed of sheep. The approach of Agroecosystem analysis, quantitative and qualitative characteristics of STT and introduced breed of sheep as well as interview to the farmer that raised STT in order to get recommendation of conservation pattern were aplied. The study show that STT sheep were isolated from the other area, and the populations tend to decrease from year to year. Qualitative characteristics of STT indicated smaller linear body measurements than those of introducted breed of sheep at the same age. Qualitative characteristics indicated that STT possess dominance body color of light brown and white (50.93% vs 41.28%. The STT mostly have one body color pattern (61.75%. The dominance spotted pattem were 1-10% of the body (60.29%, while the dominance of the head color was light brown (48.40%. Conservation pattern of STT are through natural process, in which the farmers are directly conserved, therefore the farmers do not have opportunity to develop their sheep farming. Therefore the conservation pattern recomnendation for STT sheep are by defending the location as "in situ conservation" or "on farm conservation" and giving "compensation program" to fanner because STT sheep farming less benefit than those of introduced breed of sheep.

  1. Zoonotic Enterocytozoon bieneusi Genotypes found in Brazilian sheep

    Science.gov (United States)

    The presence of Enterocytozoon bieneusi in sheep has been reported in only three countries worldwide. The present study has found E. bieneusi in Brazilian sheep for the first time; in 24/125 (19.2%) fecal samples by PCR and in 8/10 (80%) farms from three diverse locations. A significantly greater...

  2. Maxillary sinus augmentation with microstructured tricalcium phosphate ceramic in sheep.

    NARCIS (Netherlands)

    Klijn, R.J.; Hoekstra, J.W.M.; Beucken, J.J.J.P van den; Meijer, G.J.; Jansen, J.B.M.J.

    2012-01-01

    OBJECTIVE: The objective of this study was to evaluate the biological performance of osteoinductive microstructured tricalcium phosphate (MSTCP) particles in maxillary sinus floor augmentation surgery in sheep. MATERIAL AND METHODS: Sinus floor augmentation was performed in eight Swifter sheep. In e

  3. Poisoning by Poiretia punctata in cattle and sheep

    Science.gov (United States)

    Poiretia punctata (Willd.) Desv. was associated with cattle and sheep poisoning on nine farms in the State of Sergipe, northeastern Brazil. The animals were found dead or died later after showing clinical signs for up to 18 hours. Two sheep that ingested 40g/kg body weight (g/kg) of fresh P punctata...

  4. Sheep Collisions: the Good, the Bad, and the TBI

    CERN Document Server

    Courtney, Michael

    2007-01-01

    The title page of Chapter 9 in Fundamentals of Physics (Halliday, Resnick, and Walker, 8th Edition, p. 201) shows a dramatic photograph of two Big Horn sheep butting heads and promises to explain how sheep survive such violent clashes without serious injury. However, the answer presented in sample problem 9-4 (p. 213) errs in presuming an interaction time of 0.27 s which results in an unrealistically long stopping distance of 0.62 m. Furthermore, the assertion that the horns provide necessary cushioning of the blow is inconsistent with the absence of concussions in domestic breeds of hornless sheep. Results from traumatic brain injury (TBI) research allow acceleration tolerance of sheep to be estimated as 450 g facilitating an analysis of sheep collisions that is more consistent with available observations (stopping distance less than 1 cm, impact time of roughly 2 ms).

  5. Molecular evidence for the subspecific differentiation of blue sheep (Pseudois nayaur) and polyphyletic origin of dwarf blue sheep (Pseudois schaeferi).

    Science.gov (United States)

    Tan, Shuai; Zou, Dandan; Tang, Lei; Wang, Gaochao; Peng, Quekun; Zeng, Bo; Zhang, Chen; Zou, Fangdong

    2012-06-01

    Blue sheep (Pseudois nayaur), a Central Asian ungulate with restricted geographic distribution, exhibits unclear variation in morphology and phylogeographic structure. The composition of species and subspecies in the genus Pseudois is controversial, particularly with respect to the taxonomic designation of geographically restricted populations. Here, 26 specimens including 5 dwarf blue sheep (Pseudois schaeferi), which were collected from a broad geographic region in China, were analyzed for 2 mitochondrial DNA fragments (cytochrome b and control region sequences). In a pattern consistent with geographically defined subspecies, we found three deeply divergent mitochondrial lineages restricted to different geographic regions. The currently designated two subspecies of blue sheep, Pseudois nayaur nayaur and Pseudois nayaur szechuanensis, were recognized in the phylogenetic trees. In addition, the Helan Mountain population showed distinct genetic characteristics from other geographic populations, and thus should be classified as a new subspecies. In contrast, dwarf blue sheep clustered closely with some blue sheep from Sichuan Province in the phylogenetic trees. Therefore, dwarf blue sheep appear to be a subset of Pseudois nayaur szechuanensis. After considering both population genetic information and molecular clock analysis, we obtained some relevant molecular phylogeographic information concerning the historical biogeography of blue sheep. These results also indicate that western Sichuan was a potential refugium for blue sheep during the Quaternary period.

  6. 21 CFR 133.184 - Roquefort cheese, sheep's milk blue-mold, and blue-mold cheese from sheep's milk.

    Science.gov (United States)

    2010-04-01

    ... surface of the cheese may be scraped to remove surface growth of undesirable microorganisms. One or more... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Roquefort cheese, sheep's milk blue-mold, and blue-mold cheese from sheep's milk. 133.184 Section 133.184 Food and Drugs FOOD AND DRUG...

  7. Quantum localization of classical mechanics

    Science.gov (United States)

    Batalin, Igor A.; Lavrov, Peter M.

    2016-07-01

    Quantum localization of classical mechanics within the BRST-BFV and BV (or field-antifield) quantization methods are studied. It is shown that a special choice of gauge fixing functions (or BRST-BFV charge) together with the unitary limit leads to Hamiltonian localization in the path integral of the BRST-BFV formalism. In turn, we find that a special choice of gauge fixing functions being proportional to extremals of an initial non-degenerate classical action together with a very special solution of the classical master equation result in Lagrangian localization in the partition function of the BV formalism.

  8. 76 FR 31977 - Notice of Intent To Prepare an Environmental Impact Statement for Domestic Sheep Grazing...

    Science.gov (United States)

    2011-06-02

    ... Rocky Mountain bighorn sheep and domestic sheep; History, distribution, location, and population trends... or adjacent to Rocky Mountain big horn sheep habitat. In connection with the potential renewal of... to Rocky Mountain bighorn sheep habitat and will consider potential mitigation measures that can...

  9. 9 CFR 51.28 - Moving goats, sheep, and horses to be destroyed.

    Science.gov (United States)

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Moving goats, sheep, and horses to be... DESTROYED BECAUSE OF BRUCELLOSIS Indemnity for Sheep, Goats, and Horses § 51.28 Moving goats, sheep, and horses to be destroyed. Goats, sheep, and horses to be destroyed because of brucellosis must...

  10. From Classical to Quantum Transistor

    Directory of Open Access Journals (Sweden)

    Sanjeev Kumar

    2009-05-01

    Full Text Available In this article the classical transistor and the basic physics underlying the operation of single electron transistor are presented; a brief history of transistor and current technological issues are discussed.

  11. Classical Mechanics and Symplectic Integration

    DEFF Research Database (Denmark)

    Nordkvist, Nikolaj; Hjorth, Poul G.

    2005-01-01

    Content: Classical mechanics: Calculus of variations, Lagrange’s equations, Symmetries and Noether’s theorem, Hamilton’s equations, cannonical transformations, integrable systems, pertubation theory. Symplectic integration: Numerical integrators, symplectic integrators, main theorem on symplectic...

  12. Fano interference in classical oscillators

    International Nuclear Information System (INIS)

    We seek to illustrate Fano interference in a classical coupled oscillator by using classical analogues of the atom-laser interaction. We present an analogy between the dressed state picture of coherent atom-laser interaction and a classical coupled oscillator. The Autler-Townes splitting due to the atom-laser interaction is analogous to the splitting of normal-mode frequencies of a coupled oscillator. Using this analogy, we simulate and experimentally demonstrate Fano interference and the associated phenomena in three-level atoms in a coupled electrical resonator circuit. This work aims to highlight analogies between classical and quantum systems for students at the postgraduate and graduate levels. Also, the reported technique can be easily realized in undergraduate laboratories. (paper)

  13. New perspectives on classical electromagnetism

    OpenAIRE

    Cote, Paul J.

    2009-01-01

    The fallacies associated with the gauge concept in electromagnetism are illustrated. A clearer and more valid formulation of the basics of classical electromagnetism is provided by recognizing existing physical constraints as well as the physical reality of the vector potential.

  14. Elementary charges in classical electrodynamics

    OpenAIRE

    KAPU'{S}CIK, Edward

    1999-01-01

    In the framework of classical electrodynamics elementary particles are treated as capacitors. The electrostatic potentials satisfy equations of the Schrödinger type. An interesting "quantization condition" for elementary charges is derived.

  15. Probabilities for classically forbidden transitions using classical and classical path methods

    International Nuclear Information System (INIS)

    Limits are established for the applicability of purely classical methods for calculating nonreactive, inelastic transition probabilities in collinear collisions of a structureless atom and a harmonic oscillator. These limits, obtained by comparison with previous exact quantum mechanical results, indicate that such methods are inappropriate not only for ''classically forbidden'' but for many ''classically allowed'' transitions (in spite of the fact that they are widely used to calculate probabilities for such processes). A classical path method in the context of infinite-order time-dependent perturbation theory is described which yields extremely accurate transition probabilities even for the most classically forbidden transitions in the collinear atom--harmonic oscillator system. The essential features of this method are: (1) the use of the expectation value of the total interaction potential in determining the atom--oscillator (central force) trajectory, and (2) the use of the arithmetic mean of the initial and final velocities of relative motion in the (elastic) central force trajectory. This choice of interaction potential allows the relative motion to be coupled to changes in the internal state of the oscillator. The present classical method is further applied to three-dimensional atom-breathing sphere collisions, and exact quantum mechanical calculations are also carried out. Comparison of the classical path and exact quantum results shows excellent agreement both in the specific inelastic cross section and in the individual partial-wave contributions

  16. Classical Transitions for Flux Vacua

    CERN Document Server

    Deskins, J Tate; Yang, I-Sheng

    2012-01-01

    We present the simplest model for classical transitions in flux vacua. A complex field with a spontaneously broken U(1) symmetry is embedded in $M_2\\times S_1$. We numerically construct different winding number vacua, the vortices interpolating between them, and simulate the collisions of these vortices. We show that classical transitions are generic at large boosts, independent of whether or not vortices miss each other in the compact $S_1$.

  17. Classical theory of radiating strings

    Science.gov (United States)

    Copeland, Edmund J.; Haws, D.; Hindmarsh, M.

    1990-01-01

    The divergent part of the self force of a radiating string coupled to gravity, an antisymmetric tensor and a dilaton in four dimensions are calculated to first order in classical perturbation theory. While this divergence can be absorbed into a renormalization of the string tension, demanding that both it and the divergence in the energy momentum tensor vanish forces the string to have the couplings of compactified N = 1 D = 10 supergravity. In effect, supersymmetry cures the classical infinities.

  18. Gaussian Dynamics is Classical Dynamics

    OpenAIRE

    Habib, Salman

    2004-01-01

    A direct comparison of quantum and classical dynamical systems can be accomplished through the use of distribution functions. This is useful for both fundamental investigations such as the nature of the quantum-classical transition as well as for applications such as quantum feedback control. By affording a clear separation between kinematical and dynamical quantum effects, the Wigner distribution is particularly valuable in this regard. Here we discuss some consequences of the fact that when...

  19. Anderson localization from classical trajectories

    OpenAIRE

    Brouwer, Piet W.; Altland, Alexander

    2008-01-01

    We show that Anderson localization in quasi-one dimensional conductors with ballistic electron dynamics, such as an array of ballistic chaotic cavities connected via ballistic contacts, can be understood in terms of classical electron trajectories only. At large length scales, an exponential proliferation of trajectories of nearly identical classical action generates an abundance of interference terms, which eventually leads to a suppression of transport coefficients. We quantitatively descri...

  20. High frequency of chlamydial co-infections in clinically healthy sheep flocks

    Directory of Open Access Journals (Sweden)

    Sachse Konrad

    2011-06-01

    Full Text Available Abstract Background The epidemiological situation of ovine chlamydial infections in continental Europe, especially Germany is poorly characterised. Using the German state of Thuringia as a model example, the chlamydial sero- and antigen prevalence was estimated in thirty-two randomly selected sheep flocks with an average abortion rate lower than 1%. Seven vaccinated flocks were reviewed separately. Results A wide range of samples from 32 flocks were examined. Assumption of a seroprevalence of 10% (CI 95% at flock level, revealed that 94% of the tested flocks were serologically positive with ongoing infection (i.e. animals with seroconversion in nearly half (47% of the flocks. On the basis of an estimated 25% antigen prevalence (CI 95%, PCR and DNA microarray testing, together with sequencing revealed the presence of chlamydiae in 78% of the flocks. The species most frequently found was Chlamydophila (C. abortus (50% followed by C. pecorum (47% and C. psittaci genotype A (25%. Mixed infections occurred in 25% of the tested flocks. Samples obtained from the vaccinated flocks revealed the presence of C. abortus field samples in 4/7 flocks. C. pecorum was isolated from 2/7 flocks and the presence of seroconversion was determined in 3/7 flocks. Conclusions The results imply that chlamydial infections occur frequently in German sheep flocks, even in the absence of elevated abortion rates. The fact that C. pecorum and the potentially zoonotic C. psittaci were found alongside the classical abortifacient agent C. abortus, raise questions about the significance of this reservoir for animal and human health and underline the necessity for regular monitoring. Further studies are needed to identify the possible role of C. psittaci infections in sheep.

  1. Are cattle, sheep, and goats endangered species?

    Science.gov (United States)

    Taberlet, P; Valentini, A; Rezaei, H R; Naderi, S; Pompanon, F; Negrini, R; Ajmone-Marsan, P

    2008-01-01

    For about 10 000 years, farmers have been managing cattle, sheep, and goats in a sustainable way, leading to animals that are well adapted to the local conditions. About 200 years ago, the situation started to change dramatically, with the rise of the concept of breed. All animals from the same breed began to be selected for the same phenotypic characteristics, and reproduction among breeds was seriously reduced. This corresponded to a strong fragmentation of the initial populations. A few decades ago, the selection pressures were increased again in order to further improve productivity, without enough emphasis on the preservation of the overall genetic diversity. The efficiency of modern selection methods successfully increased the production, but with a dramatic loss of genetic variability. Many industrial breeds now suffer from inbreeding, with effective population sizes falling below 50. With the development of these industrial breeds came economic pressure on farmers to abandon their traditional breeds, and many of these have recently become extinct as a result. This means that genetic resources in cattle, sheep, and goats are highly endangered, particularly in developed countries. It is therefore important to take measures that promote a sustainable management of these genetic resources; first, by in situ preservation of endangered breeds; second, by using selection programmes to restore the genetic diversity of industrial breeds; and finally, by protecting the wild relatives that might provide useful genetic resources. PMID:17927711

  2. Conformational change in hamster scrapie prion protein (PrP27-30) associated with proteinase K resistance and prion infectivity.

    Science.gov (United States)

    Suzuki, Sachiko Y; Takata, Masuhiro; Teruya, Kenta; Shinagawa, Morikazu; Mohri, Shirou; Yokoyama, Takashi

    2008-02-01

    The scrapie prion protein (PrP27-30) is a crucial component of the prion and is responsible for its transmissibility. Structural information on this protein is limited because it is insoluble and shows aggregated properties. In this study, PrP27-30 was effectively dispersed using sonication under the weak alkaline condition. Subsequently, the small PrP27-30 aggregates were subjected to different pH, heat, and denaturing conditions. The loss of proteinase K (PK) resistance of PrP27-30 and prion infectivity were monitored along with spectroscopic changes. Prion inactivation could not be achieved by the loss of PK resistance alone; a significant loss of the PrP27-30 amyloid structure, which was represented by a decrease in thioflavin T fluorescence, was required for the loss of transmissibility.

  3. Decontamination of surgical instruments from prions. II. In vivo findings with a model system for testing the removal of scrapie infectivity from steel surfaces.

    Science.gov (United States)

    Lemmer, Karin; Mielke, Martin; Kratzel, Christine; Joncic, Marion; Oezel, Muhsin; Pauli, Georg; Beekes, Michael

    2008-01-01

    The unusual resistance of agents causing transmissible spongiform encephalopathies (TSEs) to chemical or thermal inactivation requires special decontamination procedures in order to prevent accidental transmission of these pathogens by surgical instruments. In the search for effective, instrument-compatible and routinely applicable decontamination procedures, a previous study [Lemmer, K., Mielke, M., Pauli, G. & Beekes, M. (2004). J Gen Virol 85, 3805-3816] identified promising reagents in an in vitro carrier assay using steel wires contaminated with the disease-associated prion protein, PrP(Sc). In the follow-up study presented here, these reagents were validated for their decontamination potential in vivo. Steel wires initially loaded with >or=3 x 10(5) LD(50) of 263K scrapie infectivity were implanted into the brains of hamsters after treatment for decontamination and subsequently monitored for their potential to trigger clinical disease or subclinical cerebral PrP(Sc) deposition within an observation period of 500 days. It was found that routinely usable reagents such as a commercially available alkaline cleaner (pH 12.2) applied for 1 h at 23 degrees C or for 10 min at 55 degrees C and a mixture of 0.2 % SDS and 0.3 % NaOH (pH 12.8) applied for 5 or 10 min at 23 degrees C achieved removal of 263K scrapie infectivity below the threshold of detection (titre reduction of >or=5.5 log(10) units). The increasing use during the past few years of similar model systems by different research groups will facilitate comparison and integration of findings on the decontamination of steel surfaces from prions. Methods identified as highly effective in the 263K steel wire model need to be validated for human TSE agents on different types of instrument surfaces. PMID:18089760

  4. Finite element modeling of blast lung injury in sheep.

    Science.gov (United States)

    Gibbons, Melissa M; Dang, Xinglai; Adkins, Mark; Powell, Brian; Chan, Philemon

    2015-04-01

    A detailed 3D finite element model (FEM) of the sheep thorax was developed to predict heterogeneous and volumetric lung injury due to blast. A shared node mesh of the sheep thorax was constructed from a computed tomography (CT) scan of a sheep cadaver, and while most material properties were taken from literature, an elastic-plastic material model was used for the ribs based on three-point bending experiments performed on sheep rib specimens. Anesthetized sheep were blasted in an enclosure, and blast overpressure data were collected using the blast test device (BTD), while surface lung injury was quantified during necropsy. Matching blasts were simulated using the sheep thorax FEM. Surface lung injury in the FEM was matched to pathology reports by setting a threshold value of the scalar output termed the strain product (maximum value of the dot product of strain and strain-rate vectors over all simulation time) in the surface elements. Volumetric lung injury was quantified by applying the threshold value to all elements in the model lungs, and a correlation was found between predicted volumetric injury and measured postblast lung weights. All predictions are made for the left and right lungs separately. This work represents a significant step toward the prediction of localized and heterogeneous blast lung injury, as well as volumetric injury, which was not recorded during field testing for sheep.

  5. Estimation of (covariance components of nematode parasites resistance and somatic cell count in dairy sheep

    Directory of Open Access Journals (Sweden)

    Sara Casu

    2010-01-01

    Full Text Available Nematode parasites and mastitis are the major animal health constraints in sheep. The aim of this study was estimating the genetic (covariances of nematode parasites resistance and somatic cell count in dairy sheep. From 2000 to 2008, Somatic Cell Score (SCS and Faecal Egg Count (FEC records were available on an experimental population consisting of 949 backcross ewes and 806 their daughters. Data were processed independently for each subpopulation in order to adjust for specific environmental effects and to obtain lactation records for both traits to be used in the genetic analysis. Variance components estimation was performed by using the REML method applied to a bi-trait repeatability animal model. Heritabilities of lactation SCS (LSCS and FEC were 0.19 and 0.16. Genetic correlation was 0.21, whereas phenotypic correlation was 0.01. The estimated heritabilities confirm that both traits could be selected by the classical quantitative approach. The genetic correlation estimate between LSCS and FEC suggests that selection for one of the two traits would not have any detrimental effect on the other one.

  6. Forecast of the Heterosis of Imported Meat Sheep by Genetic Polymorphism of Microsatellite DNA

    Institute of Scientific and Technical Information of China (English)

    ZHANG Ying-jie; LIU Yue-qin; SUN Hong-xin; SUN Shao-hua; LI Yu

    2007-01-01

    Forecast of the heterosis of Small Tail Han sheep crossed with imported meat sheep by genetic polymorphism of microsatellite DNA was done in different sheep breeds. The gene frequency, the polymorphism information contents, the number of effective alleles, the heterozygosity, and the genetic distances were studied in four imported meat sheep and Small Tail Han sheep using five microsatellite loci. The crossing effects on the Small Tail Han sheep with four imported meat sheep were tested. The results indicate that there are genetic polymorphisms at five microsatellite loci in five sheep breeds. Five microsatellite loci can be used for genetic diversity evaluation in sheep breeds. The genetic variability of Dorset is the highest, and that of the Small Tail Han sheep is the lowest in the five sheep breeds. The order of heterosis from large to small in four imported meat sheep by the analysis of genetic relationship is White-Suffolk, Black-Suffolk,Dorset, and Texel. This accords with the testing results of actual heterosis. It is feasible to forecast the heterosis of Small Tail Han sheep crossed with imported meat sheep by genetic polymorphism of microsatellite DNA, which will have an important value for sheep breeding in the future.

  7. Molecular cloning and enzymatic characterization of sheep CYP2J

    OpenAIRE

    Messina, Andrea; Nencioni, Simona; Gervasi, Pier Giovanni; Gotlinger, K. H.; Schwartzman, Michael Linado; Longo, Vincenzo

    2010-01-01

    Abstract 1. Cytochrome P450 (CYP) 2Js have been studied in various mammals, but not in sheep, as an animal model used to test veterinary drug metabolism. 2. Sheep CYP2J was cloned from liver messenger RNA (mRNA) by RACE. The cDNA, after modification at its N- and C-terminals, was expressed in Escherichia coli and the sheep CYP2J protein, purified by chromatography, was 80% homologous to human and monkey CYP2J2. 3. Reverse transcriptase-polymerase chain reaction (RT-PCR) experiments showed tha...

  8. Production and milk quality of Pag sheep

    Directory of Open Access Journals (Sweden)

    Zoran Vukašinović

    2008-02-01

    Full Text Available eep milk production and processing in last ten years show significant increase in Croatia. Market has recognized the product quality of sheep milk, so today even more number of cheese producers is interested for obtaining the protected geographical indication of products. Because of specific climate conditions on island Pag, as well as specific herbal cover, numerous aromatic plant varieties, milk, i.e. cheese, has specific taste and smell which consumers recognize, search and appreciate. Because of milk production increase and achieving better quality, production regularly controls and chemical composition analyzes and hygiene quality of sheep milk are conducted. In that propose during 2003 and 2004 years, research was carried out, which had for aim to explore milk quality of Pag sheep and to determine influence of paragenetic factors (year - climate on production, chemical composition (milk fat and proteins content and hygiene milk quality (number of somatic cells count, in two herds (A and B. Climate characteristics in 2003 and 2004 were different, regarding precipitations quantity and vegetation. Milking capacity control was carried out according to AT method. Chemical composition analyzes and hygiene quality of milk was carried out with infrared spectrometry and fluoro-opto-electronic method. During milking period in 2004, on island Pag, there were considerably more precipitations and due to the fact, vegetation was exuberant, which influenced on bigger total milk production in lactation (P<0.01 regarding to 2003. Average milk fat content (% in milk was in 2003 on family farm A, higher regarding on family farm B (P<0.01. However, because of higher quantities of produced milk on family farm B, total yield of milk fat (9.43 kg was higher (P<0.01 regarding to family farm A (7,93 kg. During 2004, differences in milk fat yield were very small and were not significant. Average daily milk quantity was from 689 mL (year 2003 to 940 mL (year 2004 on

  9. Does classical liberalism imply democracy?

    Directory of Open Access Journals (Sweden)

    David Ellerman

    2015-12-01

    Full Text Available There is a fault line running through classical liberalism as to whether or not democratic self-governance is a necessary part of a liberal social order. The democratic and non-democratic strains of classical liberalism are both present today—particularly in the United States. Many contemporary libertarians and neo-Austrian economists represent the non-democratic strain in their promotion of non-democratic sovereign city-states (start-up cities or charter cities. We will take the late James M. Buchanan as a representative of the democratic strain of classical liberalism. Since the fundamental norm of classical liberalism is consent, we must start with the intellectual history of the voluntary slavery contract, the coverture marriage contract, and the voluntary non-democratic constitution (or pactum subjectionis. Next we recover the theory of inalienable rights that descends from the Reformation doctrine of the inalienability of conscience through the Enlightenment (e.g. Spinoza and Hutcheson in the abolitionist and democratic movements. Consent-based governments divide into those based on the subjects’ alienation of power to a sovereign and those based on the citizens’ delegation of power to representatives. Inalienable rights theory rules out that alienation in favor of delegation, so the citizens remain the ultimate principals and the form of government is democratic. Thus the argument concludes in agreement with Buchanan that the classical liberal endorsement of sovereign individuals acting in the marketplace generalizes to the joint action of individuals as the principals in their own organizations.

  10. Classical approach in atomic physics

    Energy Technology Data Exchange (ETDEWEB)

    Solov' ev, E.A. [Bogoliubov Laboratory of Theoretical Physics, Joint Institute for Nuclear Research, 141980 Dubna (Russian Federation)

    2011-12-15

    The application of a classical approach to various quantum problems - the secular perturbation approach to quantization of a hydrogen atom in external fields and a helium atom, the adiabatic switching method for calculation of a semiclassical spectrum of a hydrogen atom in crossed electric and magnetic fields, a spontaneous decay of excited states of a hydrogen atom, Gutzwiller's approach to Stark problem, long-lived excited states of a helium atom discovered with the help of Poincare section, inelastic transitions in slow and fast electron-atom and ion-atom collisions - is reviewed. Further, a classical representation in quantum theory is discussed. In this representation the quantum states are treated as an ensemble of classical states. This approach opens the way to an accurate description of the initial and final states in classical trajectory Monte Carlo (CTMC) method and a purely classical explanation of tunneling phenomenon. The general aspects of the structure of the semiclassical series such as renormalization group symmetry, criterion of accuracy and so on are reviewed as well. (author)

  11. No Return to Classical Reality

    CERN Document Server

    Jennings, David

    2015-01-01

    At a fundamental level, the classical picture of the world is dead, and has been dead now for almost a century. Pinning down exactly which quantum phenomena are responsible for this has proved to be a tricky and controversial question, but a lot of progress has been made in the past few decades. We now have a range of precise statements showing that whatever the ultimate laws of Nature are, they cannot be classical. In this article, we review results on the fundamental phenomena of quantum theory that cannot be understood in classical terms. We proceed by first granting quite a broad notion of classicality, describe a range of quantum phenomena (such as randomness, discreteness, the indistinguishability of states, measurement-uncertainty, measurement-disturbance, complementarity, noncommutativity, interference, the no-cloning theorem, and the collapse of the wave-packet) that do fall under its liberal scope, and then finally describe some aspects of quantum physics that can never admit a classical understandi...

  12. Study on polymorphisms of microsatellite DNA of six Chinese indigenous sheep and goat breeds

    Institute of Scientific and Technical Information of China (English)

    QU Dongyan; HUANG Danli; CHANG Hong; YANG Zhangping; GUO Xiaoya; MAO Yongjiang; SUN Wei; GEN Rongqing; MA Yuehui; REN Xianglian; CHANG Guobing

    2007-01-01

    The genomes of six populations were screened using microsatellites as molecular markers,including Ujmuqin sheep,small-tailed Han sheep,Tan sheep,Hu sheep,Tong sheep and Yangtse River Delta (YRD) white goat.A total of seven microsatellite markers were used and genetic diversity and genetic distance were also determined.The results showed that there were 224 alleles in six populations,all seven loci showed polymorphism in all populations.The average heterozygosity of all populations was 0.949 9,and the mean polymorphism information content (PIC) of all six populations was 0.842 5-0.929 4.The six sheep (goat) populations were lowly differentiated with all loci,and the coefficient of phaenotype differentiation (Fst) was 2.6%,which was consistent with the coefficient of gene differentiation (Gst).The global heterozygote deficit across of all populations (Fit) amounted to 0.5%.The overall significant deficit of heterozygotes because of inbreeding within breeds (Fis) amounted to -2.2%.Two Unweighted Pair-group Method using Arithmetic Averages (UPGMA) dendrograms were constructed on the basis of Nei's standard genetic distance (DS) and Nei's genetic distance (DA) respectively.Hu sheep and Tong sheep were grouped at first,Ujmuqin sheep and small-tailed Han sheep clustered and then clustered with Tan sheep.Finally,Yangtse River Delta white goat joined in with all above.From this study,Ujmuqin sheep belongs to"Mongolia sheep"group,which corresponds with the historical records exactly.Ujmuqin sheep and small-tailed Han sheep,Tan sheep,Hu sheep and Tong sheep all vest in the"Mongolia sheep"group.

  13. New Approaches to Classical Liberalism

    Directory of Open Access Journals (Sweden)

    Nicolas Maloberti

    2012-01-01

    Full Text Available This article focuses on the following three novel and original philosophical approaches to classical liberalism: Den Uyl and Rasmussen's perfectionist argument from meta-norms, Gaus's justificatory model, and Kukathas's conscience-based theory of authority. None of these three approaches are utilitarian or consequentialist in character. Neither do they appeal to the notion of a rational bargain as it is typical within contractarianism. Furthermore, each of these theories rejects the idea that classical liberalism should be grounded on considerations of interpersonal justice such as those that are central to the Lockean tradition. It is argued that these three theories, despite their many attractive features, fail to articulate in a convincing manner some central classical liberal concerns.

  14. Population in the classic economics

    Directory of Open Access Journals (Sweden)

    Adnan Doğruyol

    2013-02-01

    Full Text Available Growth subject in economics is an important factor of development. Classic economics ecole indicates the population as main variable which tender of growth. On the other hand T. R. Malthus is known as economist who regards population as a problem and brings up it among the classical economists. However, Adam Smith is an intellectual who discussed population problem earlier on the classic economics theory. According to Adam Smith one of the main factors that realise the growth is labour. In addition to population made it established. The aim of this study is analyzing the mental relationship between Malthus whose name has been identified with relation between population-growth and Smith who discussed this subject first time but put it off on process of theorisation.

  15. Orf virus infection in sheep or goats.

    Science.gov (United States)

    Spyrou, V; Valiakos, G

    2015-12-14

    Orf virus, a member of the genus Parapoxvirus, is the causative agent of contagious ecthyma ('Orf'). It is a pathogen with worldwide distribution, causing significant financial losses in livestock production. The disease mainly affects sheep and goats, but various other ruminants and mammals have been reported to be infected as well. It is also a zoonotic disease, affecting mainly people who come in direct or indirect contact with infected animals (e.g. farmers, veterinarians). The disease is usually benign and self-limiting, although in many cases, especially in young animals, it can be persistent and even fatal. Production losses caused by Orf virus are believed to be underestimated, as it is not a notifiable disease. This review of literature presents all latest information regarding the virus; considerations regarding treatment and prevention will be also discussed. PMID:26315771

  16. Overview of Classical Swine Fever (Hog Cholera, Classical Swine fever)

    Science.gov (United States)

    Classical swine fever is a contagious often fatal disease of pigs clinically characterized by high body temperature, lethargy, yellowish diarrhea, vomits and purple skin discoloration of ears, lower abdomen and legs. It was first described in the early 19th century in the USA. Later, a condition i...

  17. Neutrophil extracellular traps in sheep mastitis.

    Science.gov (United States)

    Pisanu, Salvatore; Cubeddu, Tiziana; Pagnozzi, Daniela; Rocca, Stefano; Cacciotto, Carla; Alberti, Alberto; Marogna, Gavino; Uzzau, Sergio; Addis, Maria Filippa

    2015-01-01

    Neutrophil extracellular traps (NETs) are structures composed of DNA, histones, and antimicrobial proteins that are released extracellularly by neutrophils and other immune cells as a means for trapping and killing invading pathogens. Here, we describe NET formation in milk and in mammary alveoli of mastitic sheep, and provide a dataset of proteins found in association to these structures. Nucleic acid staining, immunomicroscopy and fluorescent in-situ hybridization of mastitic mammary tissue from sheep infected with Streptococcus uberis demonstrated the presence of extranuclear DNA colocalizing with antimicrobial proteins, histones, and bacteria. Then, proteomic analysis by LTQ-Orbitrap Velos mass spectrometry provided detailed information on protein abundance changes occurring in milk upon infection. As a result, 1095 unique proteins were identified, of which 287 being significantly more abundant in mastitic milk. Upon protein ontology classification, the most represented localization classes for upregulated proteins were the cytoplasmic granule, the nucleus, and the mitochondrion, while function classes were mostly related to immune defence and inflammation pathways. All known NET markers were massively increased, including histones, granule proteases, and antimicrobial proteins. Of note was the detection of protein arginine deiminases (PAD3 and PAD4). These enzymes are responsible for citrullination, the post-translational modification that is known to trigger NET formation by inducing chromatin decondensation and extracellular release of NETs. As a further observation, citrullinated residues were detected by tandem mass spectrometry in histones of samples from mastitic animals. In conclusion, this work provides novel microscopic and proteomic information on NETs formed in vivo in the mammary gland, and reports the most complete database of proteins increased in milk upon bacterial mastitis. PMID:26088507

  18. Changes in hypothalamus in continuously irradiated sheep

    Energy Technology Data Exchange (ETDEWEB)

    Arendarcik, J.; Stanikova, A.; Rajtova, V.; Molnarova, M. (Vysoka Skola Veterinarska, Kosice (Czechoslovakia))

    1983-09-01

    Neurosecretion, PAS-positive mucopolysaccharides and the Nissl substance were studied in the neurons of the rostral, medial and caudal hypothalamus of continuously irradiated ewes. The study was performed on 21 ewes of the Slovak Merino breed of a live weight of 34 kg. The animals were in the period of physiological anoestrus and their age was two to three years. The first group of six ewes was the control. The second group included 15 sheep irradiated with a total dose of 6.7 Gy (700 R) for seven days. Co/sup 60/ was used as the source of irradiation. The animals of this group were killed seven days following treatment. The ewes in the third group were left for the study of mortality. The brains were perfused with 2% buffered paraformaldehyde immediately after the bleeding of the sheep; then the brains were removed from the skulls and fixed in buffered picroformol. Paraffin slices were stained with haematoxylin-eosine, aldehyde-fuchsine and alcian blue for neurosecretion, by the PAS reaction for mucopolysaccharides and with cresyl violet for the Nissl substance. It was found that irradiation of the whole body inhibited the activity of neurosecretory cells in the rostral and medial hypothalamus, thus reducing neurosecretion. These regions also showed a reduced activity of the PAS reaction used for the demonstration of mucopolysaccharides. The observed changes also included damage of the endothelium of blood vessels with the occurrence of erythrocyte extravasates and with haemorrhages. In this way, the trophism of neurosecretory cells was affected, which is ascribed to the decrease in the amount of neurosecretory material. In the caudal hypothalamus, neurosecretion and PAS-positivity were slightly stimulated by irradiation. The Nissl substance disappeared as a result of irradiation.

  19. Comparing classical and quantum equilibration

    CERN Document Server

    Malabarba, Artur S L; Short, Anthony J

    2016-01-01

    By using a physically-relevant and theory independent definition of measurement-based equilibration, we show quantitatively that equilibration is easier for quantum systems than for classical systems, in the situation where the initial state of the system is completely known (pure state). This shows that quantum equilibration is a fundamental, nigh unavoidable, aspect of physical systems, while classical equilibration relies on experimental ignorance. When the state is not completely known, a mixed state, this framework also shows quantum equilibration requires weaker conditions.

  20. Classical planning and causal implicatures

    DEFF Research Database (Denmark)

    Blackburn, Patrick Rowan; Benotti, Luciana

    to generate clarification requests"; as a result we can model task-oriented dialogue as an interactive process locally structured by negotiation of the underlying task. We give several examples of Frolog-human dialog, discuss the limitations imposed by the classical planning paradigm, and indicate......In this paper we motivate and describe a dialogue manager (called Frolog) which uses classical planning to infer causal implicatures. A causal implicature is a type of Gricean relation implicature, a highly context dependent form of inference. As we shall see, causal implicatures are important...

  1. Classical analogy of Fano resonances

    International Nuclear Information System (INIS)

    We present an analogy of Fano resonances in quantum interference to classical resonances in the harmonic oscillator system. It has a manifestation as a coupled behaviour of two effective oscillators associated with propagating and evanescent waves. We illustrate this point by considering a classical system of two coupled oscillators and interfering electron waves in a quasi-one-dimensional narrow constriction with a quantum dot. Our approach provides a novel insight into Fano resonance physics and provides a helpful view in teaching Fano resonances

  2. Principal bundles the classical case

    CERN Document Server

    Sontz, Stephen Bruce

    2015-01-01

    This introductory graduate level text provides a relatively quick path to a special topic in classical differential geometry: principal bundles.  While the topic of principal bundles in differential geometry has become classic, even standard, material in the modern graduate mathematics curriculum, the unique approach taken in this text presents the material in a way that is intuitive for both students of mathematics and of physics. The goal of this book is to present important, modern geometric ideas in a form readily accessible to students and researchers in both the physics and mathematics communities, providing each with an understanding and appreciation of the language and ideas of the other.

  3. OSTEOPENIA in cancellous bone of sheep induced by Glucocorticoid alone

    DEFF Research Database (Denmark)

    Ding, Ming; Cheng, L.; Bollen, Peter;

    2008-01-01

    Introduction: There is a great need for suitable large animal models that closely resemble osteoporosis in humans, and that they have adequate bone size for bone prosthesis and biomaterial research. Previous investigations have shown that osteoporotic sheep model requires glucocorticoid (GC......) treatment for a long period of time after ovariectomy (OVX) to induce osteoporosis (1). However, no information in literature is available whether osteoporosis (OP) in sheep can be induced by application of GC alone. This study aimed to investigate effects of GC alone without OVX on three-dimensional (3-D......) microarchitectural properties and mechanical properties of sheep cancellous bone after a 7 months steroid treatment; and thus to validate a large animal model for orthopaedic implant/biomaterial research. Materials and Methods: Eighteen female sheep were randomly allocated into 3 groups: group 1 (GC-1) received GC...

  4. Arctic wildlife sketches: Dall's sheep of the Northwest Territories

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report covers Dall's sheep of the Northwest Territories. Topics covered include distribution, behavior, food, reproduction, and economic status and management.

  5. Sheep Smarter than Thought(高二适用)

    Institute of Scientific and Technical Information of China (English)

    王为成

    2002-01-01

    LONDON-Sheep, like turkeys and ostriches, are not considered the most clever animals. But British scientists said last Wednesday humans may have underestimated (低估) the woolly creatures. They could be much smarter than we think.

  6. Early Cytokine Elevation, PrPres Deposition, and Gliosis in Mouse Scrapie: No Effect on Disease by Deletion of Cytokine Genes IL-12p40 and IL-12p35

    OpenAIRE

    Tribouillard-Tanvier, Déborah; Race, Brent; Striebel, James F.; Carroll, James A.; Phillips, Katie; Chesebro, Bruce

    2012-01-01

    Neurodegenerative diseases are typically associated with an activation of glia and an increased level of cytokines. In our previous studies of prion disease, the cytokine response in the brains of clinically sick scrapie-infected mice was restricted to a small group of cytokines, of which IL-12p40, CCL2, and CXCL10 were present at the highest levels. The goal of our current research was to determine the relationship between cytokine responses, gliosis, and neuropathology during prion disease....

  7. Cerebrospinal Nematodiasis of Cattle, Sheep and Goats in Iran

    Directory of Open Access Journals (Sweden)

    J Ghafari-Charati

    2008-04-01

    Full Text Available Background: The prevalence of setariasis in cattle and cerebrospinal nematodiasis in sheep and goats were determined in two geographical regions of Iran.Methods: In two provinces of Iran: Mazandaran (zone I and Qazvine (zoneII   where sheep and goats were suffering from symptoms similar to cerebrospinal nematodiasis, the peritoneal cavities of  763 and 1020 cattle were searched for adult Setaria sp. respectively. History taking of 4770 sheep from zone I and 25550 sheep and 3190 goats from zone II were per­formed for the presence and determination of cerebrospinal nematodiasis in sheep and goats. To study pathological changes induced in central nervous system 7 sheep from zone I and 4 sheep and 2 goats from zone II with symptoms similar to CSN were necropsied.Results: Our findings revealed that 47% and 13.2% of cattle in zone I and II harboured Setaria digitata (99.45% and S. digitata (67.12% plus S.labiato-papillosa (17.46% respectively. History taking showed that each year 2.53% of sheep in zone I and 1.65% of sheep and 1.25% of goats in some districts of zone II (e.g. Roudbar Alamout  suffered from symp­toms similar to cerebrospinal nematodiasis the main clinical signs of which were difficulty in hind limbs movement (lumbar paralysis. At necropsy, no lesions were observed macroscopically in the brains as well as spinal cords. But in a few cases, central nervous system were congested  and edematous .Histopathological examination of CNS of necropsied animals showed mild leptomeningitis and eosinophilic and lymphacytic encephalomyelitis with numerous hemorrhagic tracts, degeneration and necrosis due to migration of the larvae. The cross section of nematode larvae was observed in the brain section of a sheep in zone I. Conclusion: The results of this study showed that setariasis of cattle is very prevalent in both region mainly in zone I and sheep and goats harbor low percentage of CSN but with marked pathological lesions.

  8. Serological and molecular survey of sheep infected with Mycoplasma ovipneumoniae in Xinjiang, China.

    Science.gov (United States)

    Cheng, Chen; Jun, Qiao; Qingling, Meng; Zhengxiang, Hu; Yu, Ma; Xuepeng, Cai; Zibing, Cheng; Jinsheng, Zhang; Zaichao, Zhang; Kuojun, Cai; Chuangfu, Chen

    2015-12-01

    Mycoplasma pneumonia is one of the most important infectious diseases that threaten sheep production. In order to investigate the epidemic status of Mycoplasma ovipneumoniae infection in sheep, indirect hemagglutination assay was used to analyze 1679 serum samples collected from four different breeds of sheep (Kazak sheep, Hu sheep, Merino sheep, and Duolang sheep) in six regions in Xinjiang between 2012 and 2014. One thousand one hundred sixty-nine sheep nasal swabs and 180 lungs were PCR analyzed. The results showed that the average positive rates of the serum samples were 17.75 %. The positive rates were between 9.76 and 30.61 % in the four breeds. Among them, the Hu sheep had a significantly higher rate than other breeds (P M. ovipneumoniae in Xinjiang, China.

  9. Productivity Change in the Australian Sheep Industry Revisited

    OpenAIRE

    Villano, Renato A.; Fleming, Euan M.; Farrell, Terence C.; Fleming, Pauline

    2006-01-01

    Recent low estimates of total factor productivity change for wool producers in the Australian sheep industry indicate that they are struggling to improve their performance. This evidence is at odds with the views of many technical observers of industry performance, prompting us to re-estimate total factor productivity change for farmers in a benchmarking group in south-west Victoria who had been the subject of such a negative finding. An important transformation in sheep production in Austral...

  10. Pyrrolizidine alkaloid poisoning of sheep in New South Wales.

    Science.gov (United States)

    Seaman, J T

    1987-06-01

    Pyrrolizidine alkaloid poisoning of sheep in New South Wales was reviewed, based on the records of the New South Wales Department of Agriculture's Regional Veterinary Laboratories. The plant species causing significant mortalities were Echium plantagineum and Heliotropium europaeum. The syndrome of hepatogenous chronic copper poisoning was more frequently diagnosed than primary pyrrolizidine alkaloid poisoning, particularly when grazing E. plantagineum. The data indicated that adult crossbred ewes were the most commonly affected class of sheep. PMID:3632498

  11. New aspects on efficient anticoagulation and antiplatelet strategies in sheep

    OpenAIRE

    Weigand, Annika; Boos, Anja M; Ringwald, Jürgen; Mieth, Maren; Kneser, Ulrich; Arkudas, Andreas; Bleiziffer, Oliver; Klumpp, Dorothee; Horch, Raymund E; Beier, Justus P.

    2013-01-01

    Background After addressing fundamental questions in preclinical models in vitro or in small animals in vivo, the translation into large animal models has become a prerequisite before transferring new findings to human medicine. Especially in cardiovascular, orthopaedic and reconstructive surgery, the sheep is an important in vivo model for testing innovative therapies or medical devices prior to clinical application. For a wide variety of sheep model based research projects, an optimal an...

  12. An Economic Analysis of Farm Flock Sheep Production in Utah

    OpenAIRE

    Beck, Ken

    1981-01-01

    The purpose of this study was to evaluate the economic aspects of farm flock sheep production in Utah. Using 1979 as a base year, costs and returns were calculated from data obtained from twenty- six Utah farms. Characteristics that typify the states· farm flock sheep production, at this writing, with regard to: 1) the farm flock producers and 2) the farm flock enterprise, were presented. Various models were dev eloped and examined using Multiple Regression and Linear Programming analytica...

  13. Determinants of sheep and goat meat consumption in Switzerland

    OpenAIRE

    Aepli, M.; Finger, R.

    2013-01-01

    In this study, we estimated the influence of different meat prices, socio-demographic and geographic variables on sheep and goat meat demand using the Swiss household expenditure survey from 2000 to 2005, a micro data set on 20,940 households resident in Switzerland. This study is motivated by the fact that sheep and goats play a major economic role especially for small farms in Swiss agriculture and contribute to conservation of landscape and biodiversity especially in the mountain regions. ...

  14. Monitoring the on-farm welfare of sheep and goats

    OpenAIRE

    Agostino Sevi; Fabio Napolitano; Salvatore Pier Giacomo Rassu; Donato Casamassima; Mariangela Caroprese

    2009-01-01

    Schemes for on-farm welfare assessment in sheep and goats are not yet available. Factors responsible for this lack of availability are discussed in the first part of this review. Requisites for reliable methods of welfare assessment to be used in sheep and goat farms are discussed, taking into account the peculiarities of the small ruminant production systems in terms of flock management and farm location. Some housing parameters related to structures, design and micro-environment are reviewe...

  15. Do Welsh hill farmers dream of radioactive sheep?

    International Nuclear Information System (INIS)

    A low-power portable device is being used successfully in North Wales to provide precise position-logging of sheep grazing on upland hill pastures following irradiation by fallout from the Chernobyl reactor. This follows the discovery that radiation levels appear to vary significantly among sheep from the same flock, suggesting hot-spots of radiation. The design and execution of the system is described. (UK)

  16. Executive Decision-Making in the Domestic Sheep

    OpenAIRE

    A Jennifer Morton; Laura Avanzo

    2011-01-01

    Two new large animal models of Huntington's disease (HD) have been developed recently, an old world monkey (macaque) and a sheep. Macaques, with their large brains and complex repertoire of behaviors are the 'gold-standard' laboratory animals for testing cognitive function, but there are many practical and ethical issues that must be resolved before HD macaques can be used for pre-clinical research. By contrast, despite their comparable brain size, sheep do not enjoy a reputation for intellig...

  17. Induction of allergic responses to peanut allergen in sheep.

    Directory of Open Access Journals (Sweden)

    Jenna L Van Gramberg

    Full Text Available Peanut allergy is the leading cause of deaths due to food-induced anaphylaxis but despite continued research, there are currently no specific treatments available. Challenge testing is limited in patients due to the high risk of adverse reactions, emphasising the need for an appropriate animal model. In the present study we examine the induction of allergic responses in a sheep model for peanut allergy. Sheep were sensitised with peanut (PN extract and in separate injections with ovalbumin (OVA or house dust mite (HDM extract. Serum PN-specific IgE responses were detected in 40-50% of immunised sheep, while only 10% (1 of 10 sheep showed detectable OVA-specific IgE. All PN-allergic sheep tested showed an Ara h 1-specific IgE response, while four out of five allergic sheep showed an Ara h 2-specific IgE response. Animals with high serum IgE levels to HDM were also PN IgE-positive. Of the PN-sensitised animals with high PN-specific IgE, 80% also showed an immediate hypersensitivity reaction following an intradermal PN injection. This new large animal model of peanut allergy may provide a useful tool for future investigations of allergen-associated immune mechanisms and specific immunotherapy.

  18. Prevalence of Mycoplasma ovipneumoniae in desert bighorn sheep in Arizona

    Science.gov (United States)

    Justice-Allen, Anne E.; Luedtke, Clint J.; Overstreet, Matthew; Cain, James W.; Stephenson, Thomas R.

    2011-01-01

    To assess the potential for an epizootic of pneumonia to result from either natural immigration or translocation, we compared the seroprevalence to Mycoplasma ovipneumoniae in several populations of desert bighorn sheep in Arizona. We collected blood samples and nasal or oropharyngeal swabs from 124 desert bighorn sheep (Ovis canadensis nelsoni) from 6 populations in Arizona in 2009 and 2010. M. ovipneumoniae organisms were detected by PCR in 22%, whereas antibodies to M. ovipneumoniae were detected in 47% of tested bighorn sheep. Mycoplasma antibodies were not found in 2 of 6 populations, indicating some bighorn sheep populations in Arizona are naïve to this bacterium. In contrast, others had seroprevalence rates up to 80%. We were able to compare seroprevalence rates and titers over time in 9 individuals (7 individuals included in the 124 bighorn sheep sampled in 2009 and 2010, and 2 individuals originally captured in 2006). Antibody titers persisted for 12 months in individuals from the Kofa National Wildlife Refuge (n = 7) while antibody titers appeared to decline in the Kanab Creek population (n = 2). M. ovipneumoniae is present or has been present in several, but not all, populations of bighorn sheep in Arizona. The results demonstrate the importance of routine health testing for future translocation efforts to reduce disease risk for naive populations.

  19. CLASSIC APPROACH TO BUSINESS COACHING

    OpenAIRE

    Żukowska, Joanna

    2011-01-01

    The purpose of this paper is to present business coaching in a classical way. An overview of coaching definitions will be provided. Attention will be drawn to coaching components and varieties. Moreover, a brief description of coach competences and tools supporting their work will be offered. Joanna Żukowska

  20. On Classical and Quantum Cryptography

    CERN Document Server

    Volovich, I V; Volovich, Ya.I.

    2001-01-01

    Lectures on classical and quantum cryptography. Contents: Private key cryptosystems. Elements of number theory. Public key cryptography and RSA cryptosystem. Shannon`s entropy and mutual information. Entropic uncertainty relations. The no cloning theorem. The BB84 quantum cryptographic protocol. Security proofs. Bell`s theorem. The EPRBE quantum cryptographic protocol.

  1. Teaching Classical Mechanics Using Smartphones

    Science.gov (United States)

    Chevrier, Joel; Madani, Laya; Ledenmat, Simon; Bsiesy, Ahmad

    2013-01-01

    A number of articles published in this column have dealt with topics in classical mechanics. This note describes some additional examples employing a smartphone and the new software iMecaProf. Steve Jobs presented the iPhone as "perfect for gaming." Thanks to its microsensors connected in real time to the numerical world, physics…

  2. Supersymmetric classical mechanics: free case

    Energy Technology Data Exchange (ETDEWEB)

    Rodrigues, R. de Lima [Centro Brasileiro de Pesquisas Fisicas (CBPF), Rio de Janeiro, RJ (Brazil)]|[Paraiba Univ., Cajazeiras, PB (Brazil). Dept. de Ciencias Exatas e da Natureza]. E-mail: rafael@cfp.ufpb.br; Almeida, W. Pires de [Paraiba Univ., Cajazeiras, PB (Brazil). Dept. de Ciencias Exatas e da Natureza; Fonseca Neto, I. [Paraiba Univ., Campina Grande, PB (Brazil). Dept. de Fisica

    2001-06-01

    We present a review work on Supersymmetric Classical Mechanics in the context of a Lagrangian formalism, with N = 1-supersymmetry. We show that the N = 1 supersymmetry does not allow the introduction of a potencial energy term depending on a single commuting supercoordinate, {phi}(t;{theta}). (author)

  3. Relative Clauses in Classical Nahuatl

    Science.gov (United States)

    Langacker, Ronald W.

    1975-01-01

    Jane Rosenthal's paper on relative clauses in Classical Nahuatl is discussed, and it is argued that she misses an important generalization. An alternative analysis to a class of relative pronouns and new rules for the distribution of relative pronouns are proposed. (SC)

  4. Minimum signals in classical physics

    Institute of Scientific and Technical Information of China (English)

    邓文基; 许基桓; 刘平

    2003-01-01

    The bandwidth theorem for Fourier analysis on any time-dependent classical signal is shown using the operator approach to quantum mechanics. Following discussions about squeezed states in quantum optics, the problem of minimum signals presented by a single quantity and its squeezing is proposed. It is generally proved that all such minimum signals, squeezed or not, must be real Gaussian functions of time.

  5. Classical Virasoro irregular conformal block

    CERN Document Server

    Rim, Chaiho

    2015-01-01

    Virasoro irregular conformal block with arbitrary rank is obtained for the classical limit or equivalently Nekrasov-Shatashvili limit using the beta-deformed irregular matrix model (Penner-type matrix model for the irregular conformal block). The same result is derived using the generalized Mathieu equation which is equivalent to the loop equation of the irregular matrix model.

  6. Neo-classical impurity transport

    International Nuclear Information System (INIS)

    The neo-classical theory for impurity transport in a toroidal plasma is outlined, and the results discussed. A general account is given of the impurity behaviour and its dependence on collisionality. The underlying physics is described with special attention to the role of the poloidal rotation

  7. Functional Techniques in Classical Mechanics

    CERN Document Server

    Gozzi, E

    2001-01-01

    In 1931 Koopman and von Neumann extended previous work of Liouville and provided an operatorial version of Classical Mechanics (CM). In this talk we will review a path-integral formulation of this operatorial version of CM. In particular we will study the geometrical nature of the many auxiliary variables present and of the unexpected universal symmetries generated by the functional technique.

  8. Classical Music as Enforced Utopia

    Science.gov (United States)

    Leech-Wilkinson, Daniel

    2016-01-01

    In classical music composition, whatever thematic or harmonic conflicts may be engineered along the way, everything always turns out for the best. Similar utopian thinking underlies performance: performers see their job as faithfully carrying out their master's (the composer's) wishes. The more perfectly they represent them, the happier the…

  9. Supersymmetric classical mechanics: free case

    International Nuclear Information System (INIS)

    We present a review work on Supersymmetric Classical Mechanics in the context of a Lagrangian formalism, with N = 1-supersymmetry. We show that the N = 1 supersymmetry does not allow the introduction of a potencial energy term depending on a single commuting supercoordinate, φ(t;Θ). (author)

  10. No return to classical reality

    Science.gov (United States)

    Jennings, David; Leifer, Matthew

    2016-01-01

    At a fundamental level, the classical picture of the world is dead, and has been dead now for almost a century. Pinning down exactly which quantum phenomena are responsible for this has proved to be a tricky and controversial question, but a lot of progress has been made in the past few decades. We now have a range of precise statements showing that whatever the ultimate laws of nature are, they cannot be classical. In this article, we review results on the fundamental phenomena of quantum theory that cannot be understood in classical terms. We proceed by first granting quite a broad notion of classicality, describe a range of quantum phenomena (such as randomness, discreteness, the indistinguishability of states, measurement-uncertainty, measurement-disturbance, complementarity, non-commutativity, interference, the no-cloning theorem and the collapse of the wave-packet) that do fall under its liberal scope, and then finally describe some aspects of quantum physics that can never admit a classical understanding - the intrinsically quantum mechanical aspects of nature. The most famous of these is Bell's theorem, but we also review two more recent results in this area. Firstly, Hardy's theorem shows that even a finite-dimensional quantum system must contain an infinite amount of information, and secondly, the Pusey-Barrett-Rudolph theorem shows that the wave function must be an objective property of an individual quantum system. Besides being of foundational interest, results of this sort now find surprising practical applications in areas such as quantum information science and the simulation of quantum systems.

  11. EVALUATION OF ELISA METHOD TO DETECTION OF COW β-LACTOGLOBULIN IN SHEEP MILK AND SHEEP MILK PRODUCTS

    Directory of Open Access Journals (Sweden)

    Juraj Paulov

    2010-11-01

    Full Text Available The aim of work was to optimalize the ELISA method to detect the adulteration of sheep milk and sheep milk products by cow milk in the laboratory. We have focused on laboratory testing of ELISA kit (β-Lactoglobulin ELISA Set, SEDIUM R&D for detection of cow β-Lg in sheep milk order to obtain high-quality, reliable and economically advantageous method suitable for routine use in practice. The results shown that for the quality of adulteration determination  it is necessary to verify the sensitivity of applied kit by the samples dilution in accordance with the producer declared quantification range contained in the manual ELISA kit. The starting point for obtaining of relevant data was to create separate regression curves with high deter­mination coefficient, which allowed to quickly and easily detect the cow milk additions in sheep milk, cloddish sheep and Slovak sheep cheese. doi:10.5219/78  

  12. Suppressed peripheral blood lymphocyte blastogenesis in pre- and postpartal sheep by chronic heat-stress, and suppressive property of heat-stressed sheep serum on lymphocytes.

    Science.gov (United States)

    Niwano, Y; Becker, B A; Mitra, R; Caldwell, C W; Abdalla, E B; Johnson, H D

    1990-01-01

    Phytohemagglutinin (PHA) and concanavalin A (Con A)-induced blastogenesis of peripheral blood lymphocytes was examined in heat-stressed pre- and postpartal sheep. The peak responses of lymphocytes to PHA and Con A in heat-stressed sheep revealed significant reduction before and after parturition compared with those in the corresponding control animals kept under thermoneutral conditions. Furthermore, the effect of serum from control or heat-stressed sheep on PHA-induced lymphocyte blastogenesis was examined. Supplementation of serum from heat-stressed sheep significantly suppressed the blastogenesis of lymphocytes obtained from healthy sheep, bovine, and human donors. Unlike dexamethasone, heat-stressed sheep serum did not inhibit IL-2 production by PHA-stimulated human peripheral blood lymphocytes. These results indicate that the immunosuppression of heat-stressed sheep is in part mediated by serum factor(s) that can modulate T-cell function in a species nonspecific manner.

  13. From classical to quantum physics

    CERN Document Server

    Stehle, Philip

    2017-01-01

    Suitable for lay readers as well as students, this absorbing survey explores the twentieth-century transition from classical to quantum physics. Author Philip Stehle traces the shift in the scientific worldview from the work of Galileo, Newton, and Darwin to the modern-day achievements of Max Planck, Albert Einstein, Ernest Rutherford, Niels Bohr, and others of their generation. His insightful overview examines not only the history of quantum physics but also the ways that progress in the discipline changed our understanding of the physical world and forces of nature. This chronicle of the second revolution in the physical sciences conveys the excitement and suspense that new developments produced in the scientific community. The narrative ranges from the classical physics of the seventeenth-century to the emergence of quantum mechanics with the entrance of the electron, the rise of relativity theory, the development of atomic theory, and the recognition of wave-particle duality. Relevant mathematical details...

  14. Classical Probability and Quantum Outcomes

    Directory of Open Access Journals (Sweden)

    James D. Malley

    2014-05-01

    Full Text Available There is a contact problem between classical probability and quantum outcomes. Thus, a standard result from classical probability on the existence of joint distributions ultimately implies that all quantum observables must commute. An essential task here is a closer identification of this conflict based on deriving commutativity from the weakest possible assumptions, and showing that stronger assumptions in some of the existing no-go proofs are unnecessary. An example of an unnecessary assumption in such proofs is an entangled system involving nonlocal observables. Another example involves the Kochen-Specker hidden variable model, features of which are also not needed to derive commutativity. A diagram is provided by which user-selected projectors can be easily assembled into many new, graphical no-go proofs.

  15. Coupled Classical and Quantum Oscillators

    CERN Document Server

    McDermott, R M; Dermott, Rachael M. Mc; Redmount, Ian H.

    2004-01-01

    Some of the most enduring questions in physics--including the quantum measurement problem and the quantization of gravity--involve the interaction of a quantum system with a classical environment. Two linearly coupled harmonic oscillators provide a simple, exactly soluble model for exploring such interaction. Even the ground state of a pair of identical oscillators exhibits effects on the quantum nature of one oscillator, e.g., a diminution of position uncertainty, and an increase in momentum uncertainty and uncertainty product, from their unperturbed values. Interaction between quantum and classical oscillators is simulated by constructing a quantum state with one oscillator initially in its ground state, the other in a coherent or Glauber state. The subsequent wave function for this state is calculated exactly, both for identical and distinct oscillators. The reduced probability distribution for the quantum oscillator, and its position and momentum expectation values and uncertainties, are obtained from thi...

  16. Classical theory of algebraic numbers

    CERN Document Server

    Ribenboim, Paulo

    2001-01-01

    Gauss created the theory of binary quadratic forms in "Disquisitiones Arithmeticae" and Kummer invented ideals and the theory of cyclotomic fields in his attempt to prove Fermat's Last Theorem These were the starting points for the theory of algebraic numbers, developed in the classical papers of Dedekind, Dirichlet, Eisenstein, Hermite and many others This theory, enriched with more recent contributions, is of basic importance in the study of diophantine equations and arithmetic algebraic geometry, including methods in cryptography This book has a clear and thorough exposition of the classical theory of algebraic numbers, and contains a large number of exercises as well as worked out numerical examples The Introduction is a recapitulation of results about principal ideal domains, unique factorization domains and commutative fields Part One is devoted to residue classes and quadratic residues In Part Two one finds the study of algebraic integers, ideals, units, class numbers, the theory of decomposition, iner...

  17. Classical Equations for Quantum Systems

    CERN Document Server

    Gell-Mann, Murray; Gell-Mann, Murray; Hartle, James B.

    1993-01-01

    The origin of the phenomenological deterministic laws that approximately govern the quasiclassical domain of familiar experience is considered in the context of the quantum mechanics of closed systems such as the universe as a whole. We investigate the requirements for coarse grainings to yield decoherent sets of histories that are quasiclassical, i.e. such that the individual histories obey, with high probability, effective classical equations of motion interrupted continually by small fluctuations and occasionally by large ones. We discuss these requirements generally but study them specifically for coarse grainings of the type that follows a distinguished subset of a complete set of variables while ignoring the rest. More coarse graining is needed to achieve decoherence than would be suggested by naive arguments based on the uncertainty principle. Even coarser graining is required in the distinguished variables for them to have the necessary inertia to approach classical predictability in the presence of t...

  18. Classical Concepts in Quantum Programming

    CERN Document Server

    Oemer, B

    2002-01-01

    The rapid progress of computer technology has been accompanied by a corresponding evolution of software development, from hardwired components and binary machine code to high level programming languages, which allowed to master the increasing hardware complexity and fully exploit its potential. This paper investigates, how classical concepts like hardware abstraction, hierarchical programs, data types, memory management, flow of control and structured programming can be used in quantum computing. The experimental language QCL will be introduced as an example, how elements like irreversible functions, local variables and conditional branching, which have no direct quantum counterparts, can be implemented, and how non-classical features like the reversibility of unitary transformation or the non-observability of quantum states can be accounted for within the framework of a procedural programming language.

  19. Teaching Classical Mechanics using Smartphones

    CERN Document Server

    Chevrier, Joel; Ledenmat, Simon; Bsiesy, Ahmad

    2012-01-01

    Using a personal computer and a smartphone, iMecaProf is a software that provides a complete teaching environment for practicals associated to a Classical Mechanics course. iMecaProf proposes a visual, real time and interactive representation of data transmitted by a smartphone using the formalism of Classical Mechanics. Using smartphones is more than using a set of sensors. iMecaProf shows students that important concepts of physics they here learn, are necessary to control daily life smartphone operations. This is practical introduction to mechanical microsensors that are nowadays a key technology in advanced trajectory control. First version of iMecaProf can be freely downloaded. It will be tested this academic year in Universit\\'e Joseph Fourier (Grenoble, France)

  20. A Companion to Classical Receptions

    Directory of Open Access Journals (Sweden)

    A. De Villiers

    2012-03-01

    Full Text Available This recent addition to the excellent Blackwell Companions series looks at the various forms of classical reception currently being researched as well as those deemed to have future importance. The diversity and volume of the themes and approaches contained in this book are truly impressive. As Hardwick and Stray state in their introduction, this collection “has been constructed on the basis that the activators of reception are many and varied and that we all gain from encountering examples from outside our own immediate areas of knowledge” (p. 4. Throughout the book they stay true to this motto and traditional approaches to classical reception are not given prominence over more recent (sometimes contentious approaches such as film studies, cultural politics and photography. The same goes for the various cultures involved and there is even a chapter on Greek drama in South Africa.

  1. Executive decision-making in the domestic sheep.

    Directory of Open Access Journals (Sweden)

    A Jennifer Morton

    Full Text Available Two new large animal models of Huntington's disease (HD have been developed recently, an old world monkey (macaque and a sheep. Macaques, with their large brains and complex repertoire of behaviors are the 'gold-standard' laboratory animals for testing cognitive function, but there are many practical and ethical issues that must be resolved before HD macaques can be used for pre-clinical research. By contrast, despite their comparable brain size, sheep do not enjoy a reputation for intelligence, and are not used for pre-clinical cognitive testing. Given that cognitive decline is a major therapeutic target in HD, the feasibility of testing cognitive function in sheep must be explored if they are to be considered seriously as models of HD. Here we tested the ability of sheep to perform tests of executive function (discrimination learning, reversal learning and attentional set-shifting. Significantly, we found that not only could sheep perform discrimination learning and reversals, but they could also perform the intradimensional (ID and extradimensional (ED set-shifting tasks that are sensitive tests of cognitive dysfunction in humans. Their performance on the ID/ED shifts mirrored that seen in humans and macaques, with significantly more errors to reach criterion in the ED than the ID shift. Thus, sheep can perform 'executive' cognitive tasks that are an important part of the primate behavioral repertoire, but which have never been shown previously to exist in any other large animal. Sheep have great potential, not only for use as a large animal model of HD, but also for studying cognitive function and the evolution of complex behaviours in normal animals.

  2. Semi-classical signal analysis

    KAUST Repository

    Laleg-Kirati, Taous-Meriem

    2012-09-30

    This study introduces a new signal analysis method, based on a semi-classical approach. The main idea in this method is to interpret a pulse-shaped signal as a potential of a Schrödinger operator and then to use the discrete spectrum of this operator for the analysis of the signal. We present some numerical examples and the first results obtained with this method on the analysis of arterial blood pressure waveforms. © 2012 Springer-Verlag London Limited.

  3. Logical, conditional, and classical probability

    OpenAIRE

    Quznetsov, G. A.

    2005-01-01

    The propositional logic is generalized on the real numbers field. the logical function with all properties of the classical probability function is obtained. The logical analog of the Bernoulli independent tests scheme is constructed. The logical analog of the Large Number Law is deduced from properties of these functions. The logical analog of thd conditional probability is defined. Consistency encured by a model on a suitable variant of the nonstandard analysis.

  4. Classic ballet dancers postural patterns

    OpenAIRE

    Joseani Paulini Neves Simas; Sebastião Iberes Lopes Melo

    2008-01-01

    The aim of this study was to evaluate classic ballet practice and its influence on postural patterns and (a) identify the most frequent postural changes; (b) determine the postural pattern; (c) verify the existence of association of practice time and postural changes. The investigation was carried out in two stages: one, description in which 106 dancers participated; the other, causal comparative in which 50 dancers participated; and (a) questionnaire; (b) a checkerboard; (c) postural chart; ...

  5. Gauge Invariance in Classical Electrodynamics

    CERN Document Server

    Engelhardt, W

    2005-01-01

    The concept of gauge invariance in classical electrodynamics assumes tacitly that Maxwell's equations have unique solutions. By calculating the electromagnetic field of a moving particle both in Lorenz and in Coulomb gauge and directly from the field equations we obtain, however, contradicting solutions. We conclude that the tacit assumption of uniqueness is not justified. The reason for this failure is traced back to the inhomogeneous wave equations which connect the propagating fields and their sources at the same time.

  6. Classical Concepts in Quantum Programming

    OpenAIRE

    Oemer, Bernhard

    2002-01-01

    The rapid progress of computer technology has been accompanied by a corresponding evolution of software development, from hardwired components and binary machine code to high level programming languages, which allowed to master the increasing hardware complexity and fully exploit its potential. This paper investigates, how classical concepts like hardware abstraction, hierarchical programs, data types, memory management, flow of control and structured programming can be used in quantum comput...

  7. Quantum manifolds with classical limit

    CERN Document Server

    Hohmann, Manuel; Wohlfarth, Mattias N R

    2008-01-01

    We propose a mathematical model of quantum spacetime as an infinite-dimensional manifold locally homeomorphic to an appropriate Schwartz space. This extends and unifies both the standard function space construction of quantum mechanics and the manifold structure of spacetime. In this picture we demonstrate that classical spacetime emerges as a finite-dimensional manifold through the topological identification of all quantum points with identical position expectation value. We speculate on the possible relevance of this geometry to quantum field theory and gravity.

  8. Semi-classical signal analysis

    CERN Document Server

    Laleg-Kirati, Taous-Meriem; Sorine, Michel

    2010-01-01

    This study introduces a new signal analysis method called SCSA, based on a semi-classical approach. The main idea in the SCSA is to interpret a pulse-shaped signal as a potential of a Schr\\"odinger operator and then to use the discrete spectrum of this operator for the analysis of the signal. We present some numerical examples and the first results obtained with this method on the analysis of arterial blood pressure waveforms.

  9. Rindler particles and classical radiation

    International Nuclear Information System (INIS)

    We describe the quantum and classical radiation emitted by a uniformly accelerating point source in terms of the elementary processes of absorption and emission of Rindler scalar photons of the Fulling-Davies-Unruh bath observed by a co-accelerating observer. To this end we compute the rate at which a DeWitt detector emits a Minkowski scalar particle with defined transverse momentum per unit of proper time of the source and we show that it corresponds to the induced absorption or spontaneous and induced emission of Rindler particles from the thermal bath. We then take what could be called the inert limit of the DeWitt detector by considering the limit of no energy gap. As suggested by DeWitt, we identify, in this limit, the detector with a classical point source and verify the consistency of our computation with the classical result. Finally, we study the behaviour of the emission rate in D spacetime dimensions in connection with the so-called apparent statistics inversion

  10. Rindler Photons and Classical Radiation

    CERN Document Server

    Díaz, D E

    2001-01-01

    We describe the quantum and classical radiation by a uniformly accelerating point source in terms of the elementary processes of absorption and emission of Rindler scalar photons of the Fulling-Davies-Unruh bath observed by a co-accelerating observer.To this end we compute the emission rate by a DeWitt detector of a Minkowski scalar field particle with defined transverse momentum per unit of proper time of the source and we show that it corresponds to the induced absorption or spontaneous and induced emission of Rindler photons from the thermal bath. We then take what could be called the inert limit of the DeWitt detector by considering the limit of zero gap energy. As suggested by DeWitt, we identify in this limit the detector with a classical point source and verify the consistency of our computation with the classical result. Finally, we study the behavior of the emission rate in D space-time dimensions in connection with the so called apparent statistics inversion.

  11. Quantum to Classical Randomness Extractors

    CERN Document Server

    Berta, Mario; Wehner, Stephanie

    2011-01-01

    Even though randomness is an essential resource for many information processing tasks, it is not easily found in nature. The goal of randomness extraction is to distill (almost) perfect randomness from a weak source of randomness. When the source yields a classical string X, many extractor constructions are known. Yet, when considering a physical randomness source, X is itself ultimately the result of a measurement on an underlying quantum system. When characterizing the power of a source to supply randomness it is hence a natural question to ask, how much classical randomness we can extract from a quantum state. To tackle this question we here take on the study of quantum-to-classical randomness extractors (QC-extractors). We provide constructions of QC-extractors based on measurements in a full set of mutually unbiased bases (MUBs), and certain single qubit measurements. As the first application, we show that any QC-extractor gives rise to entropic uncertainty relations with respect to quantum side informat...

  12. MEAT PRODUCTIVITY OF CROSSBRED SHEEP CALVES

    Directory of Open Access Journals (Sweden)

    Degtyar A. S.

    2015-01-01

    Full Text Available The article presents the results of the control slaughter of purebred and crossbred lambs. It was found that the index of compactness and the main killer performance superiority had two or three breed lambs obtained from crosses involving sheep southern meat breed. The experimental animals were taken measurements of carcasses, which give a fairly complete and objective view of the differences in the length of the torso, hips, mascara and hip girth. There are specific differences in the yield of the most valuable cuts of the first grade the rams depending on the origin. The superiority of crossbred calves over the control for this indicator amounted to 16.4 and 33.4%. The chemical composition of the meat fine-wool lambs contained more moisture and less fat and less calories than meat crossbred animals. Increasing the hybrids values of the protein quality index indicates an increase in meat share of muscle proteins and the reduction of connective tissue, and consequently, improving the quality of the raw meat. Animals obtained by crossing, have wide and deep body, well-developed muscles of the thighs, the best quality characteristics of meat productivity

  13. Uterine biology in pigs and sheep

    Directory of Open Access Journals (Sweden)

    Bazer Fuller W

    2012-07-01

    Full Text Available Abstract There is a dialogue between the developing conceptus (embryo-fetus and associated placental membranes and maternal uterus which must be established during the peri-implantation period for pregnancy recognition signaling, implantation, regulation of gene expression by uterine epithelial and stromal cells, placentation and exchange of nutrients and gases. The uterus provide a microenvironment in which molecules secreted by uterine epithelia or transported into the uterine lumen represent histotroph required for growth and development of the conceptus and receptivity of the uterus to implantation. Pregnancy recognition signaling mechanisms sustain the functional lifespan of the corpora lutea (CL which produce progesterone, the hormone of pregnancy essential for uterine functions that support implantation and placentation required for a successful outcome of pregnancy. It is within the peri-implantation period that most embryonic deaths occur due to deficiencies attributed to uterine functions or failure of the conceptus to develop appropriately, signal pregnancy recognition and/or undergo implantation and placentation. With proper placentation, the fetal fluids and fetal membranes each have unique functions to ensure hematotrophic and histotrophic nutrition in support of growth and development of the fetus. The endocrine status of the pregnant female and her nutritional status are critical for successful establishment and maintenance of pregnancy. This review addresses the complexity of key mechanisms that are characteristic of successful reproduction in sheep and pigs and gaps in knowledge that must be the subject of research in order to enhance fertility and reproductive health of livestock species.

  14. Quantum-Classical Correspondence: Dynamical Quantization and the Classical Limit

    Energy Technology Data Exchange (ETDEWEB)

    Turner, L [Los Alamos National Laboratory, Los Alamos, NM 87545 (United States)

    2004-11-12

    In only 150 pages, not counting appendices, references, or the index, this book is one author's perspective of the massive theoretical and philosophical hurdles in the no-man's-land separating the classical and quantum domains of physics. It ends with him emphasizing his own theoretical contribution to this area. In his own words, he has attempted to answer: 1. How can we obtain the quantum dynamics of open systems initially described by the equations of motion of classical physics (quantization process) 2. How can we retrieve classical dynamics from the quantum mechanical equations of motion by means of a classical limiting process (dequantization process). However, this monograph seems overly ambitious. Although the publisher's description refers to this book as an accessible entre, we find that this author scrambles too hastily over the peaks of information that are contained in his large collection of 272 references. Introductory motivating discussions are lacking. Profound ideas are glossed over superficially and shoddily. Equations morph. But no new convincing understanding of the physical world results. The author takes the viewpoint that physical systems are always in interaction with their environment and are thus not isolated and, therefore, not Hamiltonian. This impels him to produce a method of quantization of these stochastic systems without the need of a Hamiltonian. He also has interest in obtaining the classical limit of the quantized results. However, this reviewer does not understand why one needs to consider open systems to understand quantum-classical correspondence. The author demonstrates his method using various examples of the Smoluchowski form of the Fokker--Planck equation. He then renders these equations in a Wigner representation, uses what he terms an infinitesimality condition, and associates with a constant having the dimensions of an action. He thereby claims to develop master equations, such as the Caldeira

  15. Changes in bone structure of Corriedale sheep with inherited rickets: a peripheral quantitative computed tomography assessment.

    Science.gov (United States)

    Dittmer, Keren E; Firth, Elwyn C; Thompson, Keith G; Marshall, Jonathan C; Blair, Hugh T

    2011-03-01

    An inherited skeletal disease with gross and microscopic features of rickets has been diagnosed in Corriedale sheep in New Zealand. The aim of this study was to quantify the changes present in tibia from sheep with inherited rickets using peripheral quantitative computed tomography. In affected sheep, scans in the proximal tibia, where metaphysis becomes diaphysis, showed significantly greater trabecular bone mineral content (BMC) and bone mineral density (BMD). The sheep with inherited rickets had significantly greater BMC and bone area in the mid-diaphysis of the proximal tibia compared to control sheep. However, BMD in the mid-diaphysis was significantly less in affected sheep than in controls, due to the greater cortical area and lower voxel density values in affected sheep. From this it was concluded that the increased strain on under-mineralised bone in sheep with inherited rickets led to increased bone mass in an attempt to improve bone strength.

  16. Intuitionism vs. classicism a mathematical attack on classical logic

    CERN Document Server

    Haverkamp, Nick

    2015-01-01

    In the early twentieth century, the Dutch mathematician L.E.J. Brouwer launched a powerful attack on the prevailing mathematical methods and theories. He developed a new kind of constructive mathematics, called intuitionism, which seems to allow for a rigorous refutation of widely accepted mathematical assumptions including fundamental principles of classical logic. Following an intense mathematical debate esp. in the 1920s, Brouwer's revolutionary criticism became a central philosophical concern in the 1970s, when Michael Dummett tried to substantiate it with meaning-theoretic considerations.

  17. Factors of welfare reduction in dairy sheep and goats

    Directory of Open Access Journals (Sweden)

    Antonio Pazzona

    2010-01-01

    Full Text Available Scientific research on factors causing the reduction of well-being in sheep and goats is rather recent, as are studies of strategies to minimize the adverse effects of environmental challenges and improper management practices on flock welfare. Sheep and goats, considered very rustic animals, are reared prevalently under extensive production systems and are widespread mainly in marginal areas. For these reasons, only few studies on the welfare of these species have been carried out in the past. More recently, the scenario has changed, due to a gradual diffusion of intensive and semi-intensive production systems, especially in dairy sheep and goat breeds, to the growing concern of consumers about the life conditions of farmed animals, and to the issuing of a number of rules and laws on the safety of animal products and well-being of farmed livestock. As a consequence, several research groups have turned their attention to the welfare of sheep and goats. Nevertheless, information on this topic is still scarce. This paper reviews major critical points regarding the endangerment of welfare in farmed sheep and goats. Climatic extremes and seasonal fluctuations in herbage amount and quality are discussed as important causes of the reduction of well-being in extensive production systems, which can impair production efficiency of grazing animals and dramatically affect the welfare and health status of sheep and goats. Space allowance and structures of sheep and goat houses are described as the main potential sources of discomfort for housed flocks, together with inadequate control of micro-environment, and inappropriate milking procedures and human-animal interactions. Recent studies on the impact of high ambient temperature, different ventilation regimes, high stocking densities, reduced airspace and poor litter management on behaviour, immune and endocrine response, and on performance of sheep and goats are discussed. The effects of inadequate milking

  18. A probable radiation-induced epidermal carcinoma in a sheep

    International Nuclear Information System (INIS)

    The sheep discussed in this report was one of 12 wether lambs given daily doses of 144Ce-144Pr to investigate the effect of radionuclides on the alimentary tract. The sheep received 20 mCi daily over a 16 day period when treatment was discontinued due to the development of sever diarrhea and later anorexia. Changes in the sheep reported (alopecia, ulceration, disappearance of adnexa, and fibrous replacement of the dermal collagen) indicate a radiation dose in excess of that used in previous experiments. About 4.5 yr after dosing, a firm enlargement was noticed in the right ventrolateral coccygeal region. As the enlargement increased in size, ulceration and bacterial infection occurred. The sheep was killed 59 months after initial treatment and a necropsy performed. The findings were consistent with the diagnosis of locally invasive squamouscell carcinoma. The authors feel that the relative rarity of epidermal carcinomas in sheep, exposure of the coccygeal area to large doses of irradiation, and the carcinogenic effect of radiation indicates a probable cause-and-effect relationship of radiation and tumour development. (U.K.)

  19. Implications of Genotype by Environment Interactions in Dairy Sheep Welfare

    Directory of Open Access Journals (Sweden)

    Dinu Gavojdian

    2014-05-01

    Full Text Available Small ruminants are the most extensively farmed livestock species in Europe, as a result being extremely exposed to natural hazards which leads to strong interactions between genotype and environment. Aim of the current review was to outline and discuss the main welfare issues and economic implications with regards to the genotype by environment interactions in dairy sheep. Researches concerning the additive genetic effect on milk yield, shown that this accounts only for 10%, while the milk production is 90% influenced by environmental factors, highlighting the major role that management and nutrition play in the dairy production of sheep. Nowadays, dairy sheep breeds (e.g. Eastern Friesian and Lacaune, are being introduced and reared in various countries under an extremely wide range of rearing conditions, without adequate knowledge on their acclimatization to the new specific conditions. It was concluded that a welfare assessment protocol for dairy sheep does not exist up today, moreover, there is a serious lack of data concerning the genetic and environmental factors affecting the welfare status of dairy sheep at farm level under different production systems.

  20. Puma predation on radiocollared and uncollared bighorn sheep

    Directory of Open Access Journals (Sweden)

    Johnson Christine K

    2009-11-01

    Full Text Available Abstract Background We used Global Positioning System (GPS data from radiocollared pumas (Puma concolor to identify kill sites of pumas preying upon an endangered population of bighorn sheep (Ovis canadensis in southern California. Our aims were to test whether or not pumas selected radiocollared versus uncollared bighorn sheep, and to identify patterns of movement before, during, and after kills. Findings Three pumas killed 23 bighorn sheep over the course of the study, but they did not preferentially prey on marked (radiocollared versus unmarked bighorn sheep. Predation occurred primarily during crepuscular and nighttime hours, and 22 kill sites were identified by the occurrence of 2 or more consecutive puma GPS locations (a cluster within 200 m of each other at 1900, 0000, and 0600 h. Conclusion We tested the "conspicuous individual hypothesis" and found that there was no difference in puma predation upon radiocollared and uncollared bighorn sheep. Pumas tended to move long distances before and after kills, but their movement patterns immediately post-kill were much more restricted. Researchers can exploit this behaviour to identify puma kill sites and investigate prey selection by designing studies that detect puma locations that are spatially clustered between dusk and dawn.

  1. Sheep production as a Senecio spp. control tool

    Directory of Open Access Journals (Sweden)

    Paulo Mota Bandarra

    2012-10-01

    Full Text Available Since poisoning by Senecio spp. is one of the main causes of cattle death in southern Brazil, control of these plants is a priority for the local livestock production. After the pasture has been mowed, grazing by 16 sheep was efficient for controlling Senecio brasiliensis and Senecio madagascariensis populations in a 5.5-hectare area that had long been severely infested with these species. A total of 28,629 plants among S. brasiliensis (flower-of-souls, 10,122 and S.madagascariensis (fireweed, 18,507 were almost completely eliminated in a two-year period. The number of sheep was kept at 3.0 stock units/ha, but a variable number of cattle were temporarily stocked according to pasture availability. The major sanitary practice applied to the sheep was anthelmintic administration. Liver biopsies taken from sheep and cattle before and after experimental period didn't reveal any change associable with seneciosis. The performance levels of the sheep were comparable to those observed in flocks managed under traditional extensive grazing systems in southern Brazil.

  2. COMPARATIVE PHARMACOKINETIC STUDIES ON OXYTETRACYCLINE IN CAMELS, SHEEP AND GOATS

    Directory of Open Access Journals (Sweden)

    Mohammed H. Al-Nazawi

    2003-12-01

    Full Text Available Kinetics of long-acting oxytetracycline (OTC injected intravenously (IV at a dose of 5 mg/kg was determined in each of eight camels, sheep and goats. The disposition of OTC was described by two-compartment open model. Two elimination half-lives were recorded for the camel (81 min and 46.1 h, whereas in sheep and goats these were 3.2 and 3.4 h, respectively. The peak plasma concentration was 10.2, 850 and 780 g/ml at 5 minutes in camel, sheep and goats, respectively. The values of volume of distribution were 1.4, 13.4 and 12.1 litre/kg for the camels, sheep and goats, respectively. In sheep and goats, values of t1/2, Vd and clearance were found similar but different from camel, indicating exclusive distribution and substantial storage which were consistent with oxytetracycline lipophilicity and the large fat content of camel body.

  3. Epidemiological, clinical and diagnostic aspects of sheep conidiobolomycosis in Brazil

    Directory of Open Access Journals (Sweden)

    Carla Weiblen

    2016-05-01

    Full Text Available ABSTRACT: Conidiobolomycosis is an emerging disease caused by fungi of the cosmopolitan genus Conidiobolus . Particular strains of Conidiobolus coronatus, Conidiobolus incongruus and Conidiobolus lamprauges , mainly from tropical or sub-tropical origin, cause the mycosis in humans and animals, domestic or wild. Lesions are usually granulomatous and necrotic in character, presenting two clinical forms: rhinofacial and nasopharyngeal. This review includes the main features of the disease in sheep, with an emphasis on the epidemiology, clinical aspects, and diagnosis of infections caused by Conidiobolus spp. in Brazil. In this country, the disease is endemic in the Northeast and Midwest, affecting predominantly woolless sheep breeds and occasioning death in the majority of the studied cases. The species responsible for infections of sheep are C. coronatus and C. lamprauges and the predominant clinical presentation is nasopharyngeal. These fungal infections are very important, since they compromise the health status of the sheep flock and cause serious economic losses to the sheep industry. Thus, research is needed to investigate faster tools for diagnosis and effective methods for the control and treatment of conidiobolomycosis.

  4. Attention bias to threat indicates anxiety differences in sheep.

    Science.gov (United States)

    Lee, Caroline; Verbeek, Else; Doyle, Rebecca; Bateson, Melissa

    2016-06-01

    Humans and animals show increased attention towards threatening stimuli when they are in increased states of anxiety. The few animal studies that have examined this phenomenon, known as attention bias, have applied environmental manipulations to induce anxiety but the effects of drug-induced anxiety levels on attention bias have not been demonstrated. Here, we present an attention bias test to identify high and low anxiety states in sheep using pharmacological manipulation. Increased anxiety was induced using 1-methyl-chlorophenylpiperazine (m-CPP) and decreased anxiety with diazepam, and then we examined the behaviour of sheep in response to the presence of a dog as a threat. Increased attention towards the threat and increased vigilance were shown in sheep that received the m-CPP and reduced in sheep receiving the diazepam. The modulated attention towards a threat displayed by the m-CPP and diazepam animals suggests that attention bias can assess different levels of anxiety in sheep. Measuring attention bias has the potential to improve animal welfare assessment protocols. PMID:27277950

  5. Prevalence of Tick Infestation and Theileriosis in Sheep and Goats

    Directory of Open Access Journals (Sweden)

    Nausheen Irshad, M. Qayyum, M. Hussain1 and M. Qasim Khan1*

    2010-07-01

    Full Text Available The present study was carried out to determine the prevalence of tick infestation and theileriosis in small ruminants maintained at National Agricultural Research Centre (NARC Islamabad and Barani Livestock Production Research Institute (BLPRI Kherimurat district Attock, Pakistan. A total of 662 animals (219 sheep and 443 goats were screened for the presence of ticks. Of these, 95(43.37% sheep and 184(41.53% goats were found infested with different species of ticks. The difference in prevalence of ticks between two farms in sheep and goats (combined was statistically significant (P≤0.01. Difference in the prevalence during different months of study at NARC was non significant (χ2=0.95596, whereas at BLPRI this difference was significant (P≤ 0.01. Ticks were identified on the basis of their morphological features. Rhipicephalus spp was found to be the most abundant tick infesting both in sheep and goats. Prevalence of theileriosis in sheep was 7.36% (7/95, while in goats it was 3.8% (7/184, the difference being statistically non significant (χ2=0.6427.

  6. Growth characterisics of Garut sheep and its crossbred

    Directory of Open Access Journals (Sweden)

    Ismeth Inounu

    2008-03-01

    Full Text Available Based on previous study it is agreed that Von Bertalanffy model is the best fitted growth curve model with highest acuracy compared to Gompertz or Logistic models. For that reason in this study Von Bertalanffy model was used to study growth characterisics of Garut sheep and its crossbred. Relative superiority of crossbred sheep compared to Garut sheep in mature size parameter (A based on Von Bertalanffy model were respectively: M. charolain X Garut = 19.26%; Hair sheep X Garut = 8.08% and MG X HG or HG X MG = 4.22%. While relative superiority of crossbreds compared to Garut in rate of maturing (k were respectively: MG = -4.91%; HG = -1.34% dan MHG/HMG = 6.05%. Based on its relative superiority mature size parameter (A and rate of maturing (k MHG sheep had prospect for more developed due to its performance in term of high mature body weight, faster in reaching standard of slaughter body weight (35 kg at 440 days, and it is considere as more eficient in biological and economicaly.

  7. Transvaginal ultrasound ovarian diathermy: sheep as an experimental model

    Directory of Open Access Journals (Sweden)

    Pimentel Anita M

    2012-01-01

    Full Text Available Abstract Background Some techniques of transvaginal ovarian drilling have been previously described. Nevertheless a monopolar transvaginal ovarian cauterization, that use the expertise and safety of transvaginal puncture for oocyte captation seems to be an easier and feasible approach. The aim of this study was to develop a minimally invasive ovarian cauterization technique under transvaginal ultrasound control, and to evaluate the safety of the transvaginal ovarian monopolar cauterization, female sheep at reproductive age were used as an experimental model. Findings An experimental study was performed in a university research center. Seventeen female sheep (15 Corriedale e 2 Suffolk in reproductive age were submitted to transvaginal ovarian cauterization with a monopolar Valleylab Force 2 electrocautery. Macroscopic and microscopic lesions were assessed. Ovarian size were 1.31 cm2 ± 0,43 (Corriedale and 3.41 cm2 ± 0,64 (Suffolk. From 30 ovaries from Corriedale sheep punctured, only 3 were cauterized, presenting macroscopic and typical microscopic lesion. In the Suffolk sheep group, only one ovary was cauterized. No lesion could be found in the needle path. Conclusions This is the first experimental animal model described for ovarian cauterization needle guided by transvaginal ultrasound. The sheep does not seem to be the ideal animal model to study this technique. Another animal model, whose ovaries are better identified by transvaginal ultrasound should be sought for this technique, theoretically less invasive, before it could be offered safely to women with polycystic ovary syndrome.

  8. EFFECTS OF ETHANOL DURING GIARDIASIS IN SHEEP INTESTINE

    Directory of Open Access Journals (Sweden)

    Muzaiyan Ahmed Khan

    2012-01-01

    Full Text Available Infections with Giardia lamblia are one of the most common intestinal maladies in the world. These infections can lead to acute diarrhea, cramps, and nausea, although asymptomatic infections are the most common. Although most infections are controlled by an effective immune response, some individuals develop chronic disease. The effects of Giardia lamblia infection on D-glucose uptake and brush border enzymes was studied in ethanol fed sheep. Giardia lamblia trophozoite counts were significantly lower in the intestine of ethanol fed sheep than in the controls. Also sodium dependant uptake of D-glucose and brush border enzymes was significantly reduced in the Giardia lamblia infected sheep intestine. There was no change in sodium dependent D-glucose transporter (SGLT-1 and brush border lactase was reduced in Giardia lamblia infected sheep compared with those of controls. However, the mRNA levels encoding these proteins in ethanol fed animals and control animals were in the sheep intestine. The D-glucose malabsorption was observed and probably it causes a significant decrease in activity of disaccharidases in Giardia lamblia infection.

  9. Assessment of snapper (Pagrus auratus) natural IgM binding to bromelain treated sheep erythrocytes.

    Science.gov (United States)

    Morrison, Richard N; Bruce Lyons, A; Nowak, Barbara F; Hayball, John D

    2005-01-01

    Normal snapper (Pagrus auratus Bloch and Schneider) serum was examined for natural IgM that binds to protease (bromelain) treated sheep erythrocytes (BrSRBC) in a model assay system that has been used to appraise natural IgM of various mammals. Normal snapper serum lysed BrSRBC while haemolysis was abrogated by heat inactivation of serum and in divalent cation-deficient conditions, indicative of classical complement mediated lysis. In addition, heat inactivated normal snapper serum agglutinated BrSRBC while phosphatidylcholine (PtC) liposomes partially inhibited both haemolysis and agglutination. Inhibition of haemolysis and agglutination may have been mediated by an interaction between immunoglobulin (Ig) and PtC as protein A purified snapper Ig bound to PtC liposomes. However it is not known if this binding was PtC specific nor if the binding was initiated by either the Fab and/or Fc domains of snapper Ig. BrSRBC plaque forming cells (PFC) were detected in the peritoneal cavity, spleen, head kidney and peripheral blood of normal snapper. The greatest proportion of BrSRBC PFC per B cell was within the peritoneal cavity followed by the spleen, peripheral blood and head kidney. Together, these data suggest that normal snapper serum may contain natural Ig that binds BrSRBC, activating the classical complement cascade.

  10. Field evaluation of an orf vaccine in sheep and goat flocks with high neonatal mortality

    OpenAIRE

    Giadinis Nektarios D; Filliusis George; Lafi Shawkat Q.; Panousis Nikolaos; Pourliotis Konstantinos; Bojkovski Jovan; Karatzias Harilaos

    2007-01-01

    A high percent of annual neonatal mortality attributed to orf infection was observed between 2001 and 2004 in 2 sheep and 2 mixed (sheep and goat) flocks of Northern Greece. In order to protect the neonatal lambs and kids from orf infection a commercially available live orf vaccine was used. Pregnant sheep and goats were vaccinated subcutaneously a month before parturition, while 10 sheep and 10 goats in each flock remained unvaccinated and were used as negative controls. The vaccine was sign...

  11. The Relation between Classical and Quantum Electrodynamics

    Directory of Open Access Journals (Sweden)

    Mario Bacelar Valente

    2011-01-01

    Full Text Available Quantum electrodynamics presents intrinsic limitations in the description of physical processes that make it impossible to recover from it the type of description we have in classical electrodynamics. Hence one cannot consider classical electrodynamics as reducing to quantum electrodynamics and being recovered from it by some sort of limiting procedure. Quantum electrodynamics has to be seen not as an more fundamental theory, but as an upgrade of classical electrodynamics, which permits an extension of classical theory to the description of phenomena that, while being related to the conceptual framework of the classical theory, cannot be addressed from the classical theory.

  12. Pressure-assisted dissociation and degradation of "proteinase K-resistant" fibrils prepared by seeding with scrapie-infected hamster prion protein.

    Science.gov (United States)

    Akasaka, Kazuyuki; Maeno, Akihiro; Murayama, Taichi; Tachibana, Hideki; Fujita, Yuzo; Yamanaka, Hitoki; Nishida, Noriyuki; Atarashi, Ryuichiro

    2014-01-01

    The crucial step for the fatal neurodegenerative prion diseases involves the conversion of a normal cellular protein, PrP(C), into a fibrous pathogenic form, PrP(Sc), which has an unusual stability against heat and resistance against proteinase K digestion. A successful challenge to reverse the reaction from PrP(Sc) into PrP(C) is considered valuable, as it would give a key to dissolving the complex molecular events into thermodynamic and kinetic analyses and may also provide a means to prevent the formation of PrP(Sc) from PrP(C) eventually in vivo. Here we show that, by applying pressures at kbar range, the "proteinase K-resistant" fibrils (rHaPrP(res)) prepared from hamster prion protein (rHaPrP [23-231]) by seeding with brain homogenate of scrapie-infected hamster, becomes easily digestible. The result is consistent with the notion that rHaPrP(res) fibrils are dissociated into rHaPrP monomers under pressure and that the formation of PrP(Sc) from PrP(C) is thermodynamically controlled. Moreover, the efficient degradation of prion fibrils under pressure provides a novel means of eliminating infectious PrP(Sc) from various systems of pathogenic concern.

  13. Evaluation of the currently used diagnostic procedures for the detection of Brucella melitensis in sheep

    NARCIS (Netherlands)

    Bercovich, Z.; Guler, L.; Baysal, T.; Schreuder, B.E.C.; Zijderveld, van F.G.

    1998-01-01

    A study was conducted to determine whether the use of the enzyme-linked immunosorbent assay (ELISA) improves detection of brucellosis in individual sheep. Sera from 132 sheep that aborted due to B. melitensis were used to assess the efficacy of the ELISA to detect brucellosis in sheep. ELISA results

  14. 9 CFR 51.27 - Identification of goats, sheep, and horses to be destroyed.

    Science.gov (United States)

    2010-01-01

    ... horses to be destroyed. 51.27 Section 51.27 Animals and Animal Products ANIMAL AND PLANT HEALTH... DISEASES ANIMALS DESTROYED BECAUSE OF BRUCELLOSIS Indemnity for Sheep, Goats, and Horses § 51.27 Identification of goats, sheep, and horses to be destroyed. The claimant must ensure that any goats, sheep,...

  15. Classical trajectories and quantum tunneling

    CERN Document Server

    Ivlev, B I

    2003-01-01

    The problem of inter-band tunneling in a semiconductor (Zener breakdown) in a nonstationary and homogeneous electric field is solved exactly. Using the exact analytical solution, the approximation based on classical trajectories is studied. A new mechanism of enhanced tunneling through static non-one-dimensional barriers is proposed in addition to well known normal tunneling solely described by a trajectory in imaginary time. Under certain conditions on the barrier shape and the particle energy, the probability of enhanced tunneling is not exponentially small even for non-transparent barriers, in contrast to the case of normal tunneling.

  16. Lectures on classical differential geometry

    CERN Document Server

    Struik, Dirk J

    1988-01-01

    Elementary, yet authoritative and scholarly, this book offers an excellent brief introduction to the classical theory of differential geometry. It is aimed at advanced undergraduate and graduate students who will find it not only highly readable but replete with illustrations carefully selected to help stimulate the student's visual understanding of geometry. The text features an abundance of problems, most of which are simple enough for class use, and often convey an interesting geometrical fact. A selection of more difficult problems has been included to challenge the ambitious student.Writ

  17. Agglomeration Economies in Classical Music

    DEFF Research Database (Denmark)

    Borowiecki, Karol Jan

    2015-01-01

    This study investigates agglomeration effects for classical music production in a wide range of cities for a global sample of composers born between 1750 and 1899. Theory suggests a trade-off between agglomeration economies (peer effects) and diseconomies (peer crowding). I test this hypothesis...... using historical data on composers and employ a unique instrumental variable – a measure of birth centrality, calculated as the average distance between a composer’s birthplace and the birthplace of his peers. I find a strong causal impact of peer group size on the number of important compositions...

  18. Advances In Classical Field Theory

    CERN Document Server

    Yahalom, Asher

    2011-01-01

    Classical field theory is employed by physicists to describe a wide variety of physical phenomena. These include electromagnetism, fluid dynamics, gravitation and quantum mechanics. The central entity of field theory is the field which is usually a multi component function of space and time. Those multi component functions are usually grouped together as vector fields as in the case in electromagnetic theory and fluid dynamics, in other cases they are grouped as tensors as in theories of gravitation and yet in other cases they are grouped as complex functions as in the case of quantum mechanic

  19. Solar Activity and Classical Physics

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    This review of solar physics emphasizes several of the more conspicuous scientific puzzles posed by contemporary observational knowledge of the magnetic activity of the Sun. The puzzles emphasize how much classical physics we have yet to learn from the Sun. The physics of solar activity is based on the principles of Newton, Maxwell, Lorentz, Boltzmann, et. al., along with the principles of radiative transfer. In the large, these principles are expressed by magnetohydrodynamics. A brief derivation of the magnetohydrodynamic induction and momentum equations is provided, with a discussion of popular misconceptions.

  20. Status of sheep sera to bluetongue, peste des petits ruminants and sheep pox in a few northern states of India

    Directory of Open Access Journals (Sweden)

    Vinayagamurthy Balamurugan

    2008-09-01

    Full Text Available Bluetongue (BT, peste des petits ruminants (PPR and sheep pox are the most economically important viral diseases of sheep in India. Serum samples obtained from sheep in five northern states of the country were screened for antibody against these agents to explore the extent of spread of these infections. A total of 516 serum samples were screened for the presence of antibodies against BT and PPR viruses. Of these, 155 samples were also tested for antibodies against sheep pox virus. BT antibodies were found in 293 (56.8% animals, PPR virus antibodies in 215 (41.7% and sheep pox virus antibodies in 106 (68.3%. Of the serum samples tested, 25.2% were positive for antibodies against all three viruses. These findings clearly demonstrated not only the enzootic nature of disease, but also the co-existence of antibodies to more than one of these viruses which would indicate that concurrent infections were common. Therefore, control measures should focus in combating all three diseases simultaneously by exploring the possibility of a trivalent vaccine or the use of multiple genes expressing vectored vaccine.

  1. Initial observations of cheek tooth abnormalities in sheep in Slovenia.

    Science.gov (United States)

    Erjavec, V; Crossley, D

    2010-07-24

    Observations were made on a small flock of 50 sheep of the native Slovenian Jezersko-Solcava breed by investigators with dental training. The aim was to determine the range of naturally occurring dental diseases, so postmortem examinations were performed on animals slaughtered for meat or culled due to disease. Additional data were obtained by examination of 25 specimens submitted for investigation of unexplained death at a pathology centre. Seventeen (34 per cent) of the flock had incisor disease but only five became clinically ill; all these five had advanced cheek tooth disease (gingival recession, periodontal pocketing, diastemata, missing teeth, occlusal wear abnormalities, food impaction, tooth mobility, tooth fracture, tooth loss and/or jaw abscessation). Advanced cheek tooth disease was found in 21 (84 per cent) of the sheep submitted to the pathology laboratory, while only seven (28 per cent) had advanced incisor disease. The results show that, as in other countries, dental disease is a serious problem for sheep in Slovenia.

  2. Relationship between behavioural reactivity and feed efficiency in housed sheep

    DEFF Research Database (Denmark)

    Williams, Charlotte Amdi; Williams, Andrew Richard; Maloney, S.K.;

    2010-01-01

    In this study we test the hypothesis that selecting sheep for a low behavioural reactivity to stressful situations will improve their metabolic efficiency, and thereby feed efficiency, during a controlled trial in an animal house. Twenty-four Merino wethers were used, 12 each from lines selected...... for high (HBR) and low (LBR) behavioural reactivity to stressful stimuli (human presence and social isolation). The sheep were habituated to the experimental procedures for 10 days, followed by 45 days during which voluntary feed intake was measured so that total daily energy intake was quantified....... The sheep were weighed twice weekly before daily feeding. Feed efficiency was determined by measuring net feed intake, average daily weight gain and body condition score. Our hypothesis was not supported by the results of this study. There was no difference betweenLBRandHBRsheep in average daily weight gain...

  3. Bromosulphophthalein clearance rates in sheep with pyrrolizidine liver damage.

    Science.gov (United States)

    Lanigan, G W; Peterson, J E

    1979-05-01

    Sheep fed a ration containing 50% of dried Heliotropium europaeum showed a marked decline in bromosulphophthalein (BSP) fractional clearance rate during the first 3 months feeding. Thereafter, the response of individual animals varied widely on a time basis, although 3 groups could be identified. In the terminal stages, mean clearance rates were below 20% of initial values, with some sheep showing a decline in excess of 90%. Loss of liver functional capacity was generally much greater than indicated by the degree of damage revealed by histopathology. Thus, a suitably modified test could have considerable prognostic value in the field. In this investigation, all sheep with clearance rates below 0.15 died when exposed to a further period of H. europaeum feeding. PMID:475677

  4. Clinical and microbiological study of otitis externa in sheep

    Directory of Open Access Journals (Sweden)

    M. I. Al-Farwachi

    2008-01-01

    Full Text Available In this study one hundred Awassi sheep were examined clinically and bacteriologically for isolation and identification of the bacterial agents of otitis externa in sheep. The main clinical signs appeared included weakness, pale mucus membrane, auricular discharge, cough, anorexia, emaciation, and nasal discharge. Results revealed isolation of bacteria from (45% examined swabs. The most being from right ear. Younger animals were more frequently infected than older animals. Pseudomonas aeruginosa, Staphylococcus aureus, Mannheimia haemolytica, Staph. epidermidis, Pasteurella multocida, Streptococcus spp., Acintobacter spp., Escherichia coli and Klebsiella pneumonia were isolated. The results revealed that the most bacterial isolates were resistance to the bactericidal effect of the normal serum included Streptococcus pneumonia, Staphylococcus aureus, Mannheimia haemolytica. While the most bacterial isolates were produced hydroxymate siderophore included Staphylococcus aureus, Mannheimia haemolytica, Streptococcus pneumonia. The obtained results indicated to the importance of determination of serum resistance as a bacterial virulence factor in otitis externa in sheep.

  5. Forage selection by teddy goats versus sheep on thal ranges

    International Nuclear Information System (INIS)

    Grazing behaviours of Teddy goats and Thalli sheep were studied on rangelands of ThaI. Bite count method was used to determine the dietary composition of both animal species. The overall preference of Teddy goats was higher for Khabble grass (Cynodon dactylon), which was 40.57% of the total number of bite made on different plant species during the study period (March-July). Teddy goats utilized a wide range of browsing plant species like Wan (Salvadora oleoides), Phog (Calligonum polygonoides), Babil (Acacia jacquemontii), Jandi (Prosopis spicigera) etc. Browsing species were major component (>50%) of goat diets dur- ing March through June. Whereas Thalli sheep had been consistent in their heavy use of Khabble grass (overall 89.27%). Browsing plant species were not an important component of their diets. Teddy goats and Thalli sheep were competitive for Khabble grass particularly at its vegetative growth stage. (author)

  6. Classical Electron Theory and Conservation Laws

    OpenAIRE

    Kiessling, Michael K. -H.

    1999-01-01

    It is shown that the traditional conservation laws for total charge, energy, linear and angular momentum, hold jointly in classical electron theory if and only if classical electron spin is included as dynamical degree of freedom.

  7. Pseudoclassical fermionic model and classical solutions

    International Nuclear Information System (INIS)

    We study classical limit of fermionic fields seen as Grassmann variables and deduce the proper quantization prescription using Dirac's method for constrained systems and investigate quantum meaning of classical solutions for the Thirring model. (author)

  8. The revision of classical stock model

    Institute of Scientific and Technical Information of China (English)

    叶柏青; 王洪利

    2001-01-01

    On the basis of the analysis of classical stock model, according to the limitation of the model, the article puts forward the revision of classical model and enforces the applicability of the stock model.

  9. The revision of classical stock model

    Institute of Scientific and Technical Information of China (English)

    YE Bai-qing; WANG Hong-li

    2001-01-01

    On the basis of the analysis of classical stock model, according to th e limitation of the model, the article puts forward the revision of classical mo del and enforces the applicability of the stock model.

  10. Lagrangian formalism and retarded classical electrodynamics

    OpenAIRE

    Jan, Xavier; Llosa, Josep; Molina, Alfred

    1989-01-01

    Unlike the 1/c2 approximation, where classical electrodynamics is described by the Darwin Lagrangian, here there is no Lagrangian to describe retarded (resp., advanced) classical electrodynamics up to 1/c3 for two-point charges with different masses.

  11. Hygiene assessment of sheep slaughter cycle

    Directory of Open Access Journals (Sweden)

    Pyz-Łukasik Renata

    2014-06-01

    Full Text Available The purpose of the study was to determine microbial contamination of mutton carcass surface with regard to the number of the slaughtered animals. The total bacterial load and Enterobacteriaceae and enterococci counts were determined. Sampling for microbiological analysis as well as detection and enumeration of each microorganism group were performed according to the Polish Standards. No significant effect of the order of the slaughtering animals during the slaughter day on total bacterial count on mutton carcass surfaces was found. The overall bacterial contamination of mutton carcasses were between 1.0 × 103 cfu/cm2 (3.0 log - stage I and 2.5 × 103 cfu/cm2 (3.4 log - stage III. No significant difference among the slaughter cycles, as indicated by total microbial numbers was observed. The obtained daily mean log values ranged from 4.7 × 102 (2.67 log and 7.6 × 103 (3.88 log cfu/cm2. The daily log mean values were lower than the maximal bacteria count (M set out for hygiene standard of sheep slaughter process by the Commission Regulation 2073/2005. Bacteria belonging to the Enterobacteriaceae family were recovered from 21 (65.6% samples while enterococci were identified in 28 (87.5% samples. In most cases, significant differences in the level of contamination with bacteria isolated from the carcasses at each stage of a daily slaughter cycle, were not observed. At stage III, significantly higher levels of bacterial contamination (0.86 and 1.31 log cfu/cm2 respectively were established as compared to stage I (0.37 and 0.58 log cfu/cm2 respectively. There were no Salmonella-positive samples determined. Importantly, the number of slaughtered animals during a slaughter day did not influence bacterial contamination on carcass surface if the successful application of HACCP control system was combined with the implementation of optimal sanitary supervision.

  12. Handmade cloned transgenic sheep rich in omega-3 Fatty acids.

    Directory of Open Access Journals (Sweden)

    Peng Zhang

    Full Text Available Technology of somatic cell nuclear transfer (SCNT has been adapted worldwide to generate transgenic animals, although the traditional procedure relies largely on instrumental micromanipulation. In this study, we used the modified handmade cloning (HMC established in cattle and pig to produce transgenic sheep with elevated levels of omega-3 (n-3 fatty acids. Codon-optimized nematode mfat-1 was inserted into a eukaryotic expression vector and was transferred into the genome of primary ovine fibroblast cells from a male Chinese merino sheep. Reverse transcriptase PCR, gas chromatography, and chromosome analyses were performed to select nuclear donor cells capable of converting omega-6 (n-6 into n-3 fatty acids. Blastocysts developed after 7 days of in vitro culture were surgically transplanted into the uterus of female ovine recipients of a local sheep breed in Xinjiang. For the HMC, approximately 8.9% (n  =925 of reconstructed embryos developed to the blastocyst stage. Four recipients became pregnant after 53 blastocysts were transplanted into 29 naturally cycling females, and a total of 3 live transgenic lambs were produced. Detailed analyses on one of the transgenic lambs revealed a single integration of the modified nematode mfat-1 gene at sheep chromosome 5. The transgenic sheep expressed functional n-3 fatty acid desaturase, accompanied by more than 2-folds reduction of n-6/n-3 ratio in the muscle (p<0.01 and other major organs/tissues (p<0.05. To our knowledge, this is the first report of transgenic sheep produced by the HMC. Compared to the traditional SCNT method, HMC showed an equivalent efficiency but proved cheaper and easier in operation.

  13. Detection of Chlamydophila abortus in Sheep (Ovis aries in Mexico

    Directory of Open Access Journals (Sweden)

    Juan M. Jiménez-Estrada

    2008-01-01

    Full Text Available Chlamydophila abortus is one of the pathogens which induce abortion in small ruminants; this pathogen has a tropism for ruminant placenta and causes the disease commonly referred to as Ovine Enzootic Abortion (OEA. In Europe are estimated economic losses of around 20 million pounds a year by OEA. In the American Continent the disease has been reported only in Canada, the United States, Colombia and Chile while in Mexico it is unknown whether OEA is common and it is causing abortions in flocks of sheep from “Estado de Mexico”. The objective of this study was investigating the prevalence of anti-Chlamydophila abortus IgG antibodies and detection of C. abortus DNA in sheep with clinical abort history by mean of ELISA assay (C. abortus ELISA, Institute Pourquier, Montpellier, France and molecular identification of the principal outer membrane protein (POMP 90-91B gene by PCR, respectively. A cross-sectional study was carried out to enroll and random sample of ewes from november 2003 until march 2005. A total of 349 sera and vaginal swabs samples were collected from 35 flocks of sheep from Xalatlaco. The results showed that the seropositive rate was 31.1% (14/45 for healthy and 21.3% (65/304 for sheep with history clinical of abort. In vaginal swabs, the PCR showed 0% (0/45 for healthy animals and 0.65% (2/304 for aborted sheep. Samples from the lungs and liver of the fetus of one of these animals were also positive for C. abortus. In conclusion, these results confirmed that infection with C. abortus is common and is affecting sheep flocks in the Mexican highlands. Therefore, is necessary that the authorities responsible for animal welfare in Mexico (SAGARPA to set up appropriate epidemiological surveillance and control programs to eradicate this disease.

  14. Radionuclides in sheep grazing near old uranium mines

    Energy Technology Data Exchange (ETDEWEB)

    Carvalho, Fernando P.; Oliveira, Joao M.; Malta, M. [Instituto Superior Tecnico/Campus Tecnologico e Nuclear/ (IST/CTN), Universidade de Lisboa, Estrada Nacional 10 - ao km 139,7, - 2695-066 Bobadela LRS (Portugal); Lemos, M.E. [Servicos de Alimentacao e Veterinaria da Regiao Centro, Bairro Na Sra dos Remedios, 6300 Guarda (Portugal); Vala, H.; Esteves, F. [Escola Superior Agraria de Viseu, Quinta da Alagoa, Estrada de Nelas, Ranhados,3500-606 Viseu (Portugal)

    2014-07-01

    During the past century extensive uranium mining took place in Portugal for radium and uranium production. Many uranium deposits were mined as open pits and after ore extraction and transportation to milling facilities, mining wastes were left on site. One uranium ore mining site, Boco Mine, was extracted in the 1960's and 70's and mining waste and open pits were left uncovered and non-remediated since closure of uranium mining activities. During the nineties a quarry for sand extraction was operated in the same site and water from a local stream was extensively used in sand sieving. Downstream the mine areas, agriculture soils along the water course are currently used for cattle grazing. Water from this stream, and water wells, soil, pasture and sheep meat were analyzed for radionuclides of the uranium series. The U- series radionuclide {sup 226}Ra was generally the highest in concentrations especially in soil, pasture, and in internal organs of sheep. Ra-226 concentrations averaged 1093±96 Bq/kg (dry weight) in soil, 43±3 Bq/kg (dw) in pasture, and 0.76±0.41 Bq/kg (dw) in muscle tissue of sheep grown there. Other sheep internal organs displayed much higher {sup 226}Ra concentrations, such as the brain and kidneys with 7.7±2.3 Bq/kg (dw) and 28±29 Bq/kg (dw), respectively. Results of tissue sample analysis for sheep grown in a comparison area were 2 to 11 times lower, depending on the tissue. Absorbed radiation doses for internal organs of sheep were computed and may exceed 20 mSv/y in the kidney. Although elevated, this absorbed radiation dose still is below the threshold for biological effects on mammals. Nevertheless, enhanced environmental radioactive contamination mainly due to radium was observed in the area of influence of this legacy uranium mine and there is potential food chain transfer for humans (authors)

  15. Reducing methane emissions in sheep by immunization against rumen methanogens.

    Science.gov (United States)

    Wright, A D G; Kennedy, P; O'Neill, C J; Toovey, A F; Popovski, S; Rea, S M; Pimm, C L; Klein, L

    2004-09-28

    This work was conducted to determine if methane emissions from sheep immunized with an anti-methanogen vaccine were significantly lower than methane emissions from non-immunized sheep, to test the effectiveness of two different vaccine formulations (VF) on methane abatement, and to compare methane emissions measured using a closed-circuit respiration chamber and the sulphur-hexafluoride (SF6) tracer technique. Thirty mature wether sheep were randomly allocated to three treatment groups (n = 10). One group received an immunization of adjuvant only on days 0 and 153 (control), a second group received an immunization with a 3-methanogen mix on days 0 and 153 (VF3 + 3), and a third group received an immunization of a 7-methanogen mix on day 0 followed by a 3-methanogen mix on day 153 (VF7 + 3). Four weeks post-secondary immunization, there was a significant 7.7% reduction in methane production per kg dry matter intake in the VF7 + 3 group compared to the controls (P = 0.051). However, methane emissions from sheep immunized with VF7 + 3 were not significantly different when compared to the sheep in the control group (P = 0.883). The average IgG and IgA antibody titres in both plasma and saliva of the VF3 + 3 immunized sheep were four to nine times higher than those immunized with VF7 + 3 (PSF6 methane estimates were consistently higher than the respiration chamber estimates and that there was no significant correlation between the SF6 methane estimates and the respiration chamber methane estimates (R2 = 0.11). PMID:15364447

  16. Variation in the prion protein sequence in Dutch goat breeds

    NARCIS (Netherlands)

    Windig, J.J.; Hoving, R.A.H.; Priem, J.; Bossers, A.; Keulen, van L.J.M.; Langeveld, J.P.M.

    2016-01-01

    Scrapie is a neurodegenerative disease occurring in goats and sheep. Several haplotypes of the prion protein increase resistance to scrapie infection and may be used in selective breeding to help eradicate scrapie. In this study, frequencies of the allelic variants of the PrP gene are determined

  17. About the modern house - and the classical

    DEFF Research Database (Denmark)

    Hauberg, Jørgen

    2010-01-01

    In text and illustrations describes the classical house and the classical city, represented by Andrea Palladio (1508-80), and the modern house, the modern city and building task, represented by Le Corbusier (1857-1965).......In text and illustrations describes the classical house and the classical city, represented by Andrea Palladio (1508-80), and the modern house, the modern city and building task, represented by Le Corbusier (1857-1965)....

  18. Technics of classical and digital photography comparsion

    OpenAIRE

    Kvapilová, Kamila

    2012-01-01

    This bachelor work is aimed at basic principles of taking photos by classical and digital camera. Describes methods for achieving of required photos by digital way and also classical taking photos on cine-film. Compares the technology of classical and digital photography from the beginning, which is getting the camera and accessories. It also describes the construction and control of the camera. Processing of photo compares the quality of digital and classic photo.

  19. The new-classical contribution to macroeconomics

    OpenAIRE

    D. LAIDLER

    2013-01-01

    This work is devoted to assessing New-Classical ideas, and to asking what of lasting importance this school of macroeconomics has contributed since the early 1970s. It deals in turn with the relationship between New-Classical Economics and Monetarism, the relative explanatory power of these two bodies of doctrine over empirical evidence, and the claims of New-Classical Economics to embody a superior analytic method. The author argues that, although the particular ways in which New-Classical M...

  20. Classical equations for quantum systems

    Energy Technology Data Exchange (ETDEWEB)

    Gell-Mann, M. (Theoretical Astrophysics Group (T-6), Los Alamos National Laboratory, Los Alamos, New Mexico 87545) (United States) (Santa Fe Institute, 1660 Old Pecos Trail, Santa Fe, New Mexico 87501); Hartle, J.B. (Department of Physics, University of California enSanta Barbara, Santa Barbara, (California) 93106)

    1993-04-15

    The origin of the phenomenological deterministic laws that approximately govern the quasiclassical domain of familiar experience is considered in the context of the quantum mechanics of closed systems such as the universe as a whole. A formulation of quantum mechanics is used that predicts probabilities for the individual members of a set of alternative coarse-grained histories that [ital decohere], which means that there is negligible quantum interference between the individual histories in the set. We investigate the requirements for coarse grainings to yield decoherent sets of histories that are quasiclassical, i.e., such that the individual histories obey, with high probability, effective classical equations of motion interrupted continually by small fluctuations and occasionally by large ones. We discuss these requirements generally but study them specifically for coarse grainings of the type that follows a distinguished subset of a complete set of variables while ignoring the rest. More coarse graining is needed to achieve decoherence than would be suggested by naive arguments based on the uncertainty principle. Even coarser graining is required in the distinguished variables for them to have the necessary inertia to approach classical predictability in the presence of the noise consisting of the fluctuations that typical mechanisms of decoherence produce. We describe the derivation of phenomenological equations of motion explicitly for a particular class of models.

  1. Entanglement-Enhanced Classical Communication

    CERN Document Server

    Herrera-Martí, David A

    2008-01-01

    This thesis will be focused on the classical capacity of quantum channels, one of the first areas treated by quantum information theorists. The problem is fairly solved since some years. Nevertheless, this work will give me a reason to introduce a consistent formalism of the quantum theory, as well as to review fundamental facts about quantum non-locality and how it can be used to enhance communication. Moreover, this reflects my dwelling in the spirit of classical information theory, and it is intended to be a starting point towards a thorough study of how quantum technologies can help to shape the future of telecommunications. Whenever it was possible, heuristic reasonings were introduced instead of rigorous mathematical proofs. This finds an explanation in that I am a self-taught neophyte in the field, and just about every time I came across a new concept, physical arguments were always more compelling to me than just maths. The technical content of the thesis is twofold. On one hand, a quadratic classific...

  2. Classical Black Holes Are Hot

    CERN Document Server

    Curiel, Erik

    2014-01-01

    In the early 1970s it is was realized that there is a striking formal analogy between the Laws of black-hole mechanics and the Laws of classical thermodynamics. Before the discovery of Hawking radiation, however, it was generally thought that the analogy was only formal, and did not reflect a deep connection between gravitational and thermodynamical phenomena. It is still commonly held that the surface gravity of a stationary black hole can be construed as a true physical temperature and its area as a true entropy only when quantum effects are taken into account; in the context of classical general relativity alone, one cannot cogently construe them so. Does the use of quantum field theory in curved spacetime offer the only hope for taking the analogy seriously? I think the answer is `no'. To attempt to justify that answer, I shall begin by arguing that the standard argument to the contrary is not physically well founded, and in any event begs the question. Looking at the various ways that the ideas of "tempe...

  3. Fluctuations in classical sum rules.

    Science.gov (United States)

    Elton, John R; Lakshminarayan, Arul; Tomsovic, Steven

    2010-10-01

    Classical sum rules arise in a wide variety of physical contexts. Asymptotic expressions have been derived for many of these sum rules in the limit of long orbital period (or large action). Although sum-rule convergence may well be exponentially rapid for chaotic systems in a global phase-space sense with time, individual contributions to the sums may fluctuate with a width which diverges in time. Our interest is in the global convergence of sum rules as well as their local fluctuations. It turns out that a simple version of a lazy baker map gives an ideal system in which classical sum rules, their corrections, and their fluctuations can be worked out analytically. This is worked out in detail for the Hannay-Ozorio sum rule. In this particular case the rate of convergence of the sum rule is found to be governed by the Pollicott-Ruelle resonances, and both local and global boundaries for which the sum rule may converge are given. In addition, the width of the fluctuations is considered and worked out analytically, and it is shown to have an interesting dependence on the location of the region over which the sum rule is applied. It is also found that as the region of application is decreased in size the fluctuations grow. This suggests a way of controlling the length scale of the fluctuations by considering a time dependent phase-space volume, which for the lazy baker map decreases exponentially rapidly with time.

  4. RISK AND RISK MANAGEMENT IN HUNGARIAN SHEEP PRODUCTION

    OpenAIRE

    Nabradi, Andras; Madai, Hajnalka

    2007-01-01

    The aim of this paper is to give an overview of the risk attitudes of Hungarian sheep producers regarding the changes they have had to go through since the political changes of 1989–1990. Moreover, the objective of this study is to strengthen the empirical basis for risk analysis by identifying the importance of farmers’ risk attitudes. The results of a nationwide survey of over 500 sheep farmers presented a framework of risk attitudes, risk sources and applied risk management techniques ...

  5. Pregnancy diagnosis in sheep: review of the most practical methods

    International Nuclear Information System (INIS)

    Various practical methods have been used for pregnancy diagnosis in sheep: radiography, rectal abdominal palpation, assessment of progesterone, assessment of estrone sulphate, RIA assay of placental lactogen, assessment of pregnancy proteins or pregnancy-associated glycoproteins, A-mode ultrasound, Doppler ultrasound and real-time B-mode ultrasonography. Real-time, B-mode ultrasonography appears to be the most practical and accurate method for diagnosing pregnancy and determining fetal numbers in sheep. Transabdominal B-mode ultrasonography achieved high accuracy for pregnancy diagnosis (94-100 %) and the determination of fetal numbers (92-99 %) on d 29 to 106 of gestation

  6. DNA polymorphism at the casein loci in sheep.

    Science.gov (United States)

    Di Gregorio, P; Rando, A; Pieragostini, E; Masina, P

    1991-01-01

    By using seven endonucleases and four bovine cDNA probes specific for alpha S1-, alpha S2-, beta-, and kappa-casein genes, nine restriction fragment length polymorphisms (RFLPs) have been found in the sheep orthologous DNA regions. In contrast to the low level of variation observed at the protein level, these DNA polymorphisms determine a high level of heterozygosity and, therefore, represent useful tools for genetic analyses since they can also be obtained without the need for gene expression. In fact, informative matings suggest that in sheep, as in cattle, the four loci are linked.

  7. Evaluation the effect of albendazole against nematodes in sheep

    Directory of Open Access Journals (Sweden)

    M. I. Al-Farwachi

    2008-01-01

    Full Text Available Six sheep farms in Mosul city, Iraq randomly selected, were surveyed for gastrointestinal nematodes resistant to Albendazole. On each of 6 sheep farms, 20 lambs were randomly distributed into two equal groups untreated control group, and albendazole (benzimidazole group (10 mg/kg BW. Faecal egg counts and larval cultures were done at 7, 14, and 21 days after anthelmintic treatment. Resistance was apparent for albendazole on 4 farms out of 6 (66.7%. Post-treatment larval cultures indicated: Strongyloides papillosus, Marshalligia marshalli, Nematodirus spathiger and Haemonchus contortus.

  8. Characterising the potential of sheep wool for ancient DNA analyses

    DEFF Research Database (Denmark)

    Brandt, Luise Ørsted; Tranekjer, Lena D.; Mannering, Ulla;

    2011-01-01

    The use of wool derived from sheep (Ovis aries) hair shafts is widespread in ancient and historic textiles. Given that hair can represent a valuable source of ancient DNA, wool may represent a valuable genetic archive for studies on the domestication of the sheep. However, both the quality...... to considerable DNA degradation. Lastly, we demonstrate that mtDNA at least can be PCR-amplified, cloned and sequenced from a range of archaeological and historic Danish, Flemmish and Greenlandic wool textile samples. In summary, our data suggest that wool offers a promising source for future ancient...... mitochondrial DNA studies....

  9. Seroprevalence of leptospires in sheep slaughtered at Sokoto metropolitan Abattoir

    Directory of Open Access Journals (Sweden)

    G. Bashiru

    2013-03-01

    Full Text Available In a study to determine the seroprevalence of leptospiralantibodies in sheep slaughtered at Sokoto metropolitan abattoir, Nigeria, bloodwas collected from 282 sheep made up of both male and female. The serum wascollected and analysed using an antigen coated IgG ELISA, out of which 20 tested positive by the ELISA giving anoverall prevalence of 7.1%. Prevalences recorded for age was 18.48% for ≤ 2yrsand 1.58% for > 2yrs, and sex was 3.09% for male and 12.50% for females.There was a significant (P

  10. Species identification of skins and development of sheep wool

    DEFF Research Database (Denmark)

    Brandt, Luise Ørsted

    markers mapped to the reference genome. The resolution of sheep mitochondrial DNA is, however, too low to generate detailed information of sheep population history and therefore nuclear DNA should be the focus in the future. Three studies focused on the species identification of skins. Traditional species...... PCR is still a valuable tool for species identification. For samples from degrading enviroments, such as the Danish bogs, Mass Spectrometry (MS)-based peptide sequencing was proven to be a reliable method for species identification. Moreover, MS-based peptide sequencing provided information of the age...

  11. Quantum electrodynamics in a classical approximation, 1

    International Nuclear Information System (INIS)

    Quantum electrodynamics is formulated in a classical approximation. A quantum mechanical proper-time is employed as a useful parameter, which enables us to elucidate the relationship between quantum electrodynamics and classical electrodynamics. The classical motion of a charged particle is realized as an asymptotic limit of quantum electrodynamics. (author)

  12. Collection of problems in classical mechanics

    CERN Document Server

    Kotkin, G L; ter Haar, D

    1971-01-01

    Collection of Problems in Classical Mechanics presents a set of problems and solutions in physics, particularly those involving mechanics. The coverage of the book includes 13 topics relevant to classical mechanics, such as integration of one-dimensional equations of motion; the Hamiltonian equations of motion; and adiabatic invariants. The book will be of great use to physics students studying classical mechanics.

  13. Diminuendo: Classical Music and the Academy

    Science.gov (United States)

    Asia, Daniel

    2010-01-01

    How is the tradition of Western classical music faring on university campuses? Before answering this question, it is necessary to understand what has transpired with classical music in the wider culture, as the relationship between the two is so strong. In this article, the author discusses how classical music has taken a big cultural hit in…

  14. Enrichment of cheeses manufactured from cow's and sheep's milk blends with sheep-like species-related alkylphenols.

    Science.gov (United States)

    Kilic, Meral; Lindsay, Robert C

    2005-03-01

    Enhancement of concentrations of species-related sheep-like alkylphenols, p- and m-cresols and 3- and 4-ethylphenols, in experimental Manchego-type cheeses manufactured from cow's and sheep's milk blends (80:20) by using arylsulfatases was investigated. A food-grade arylsulfatase from Aspergillus oryzae (ATCC 20719) was produced using a stimulatory medium, and crude dried cells were used as the enzyme source. Exogenous arylsulfatases from Helix pomatia and A. oryzae were added to cheese curd, and the amounts of species-related alkylphenols were measured. Arylsulfatase from H. pomatia released limited amounts of alkylphenols in the cheese only when used at a high level. Arylsulfatase from A. oryzae released substantial amounts of alkylphenols during 2 months of ripening. The concentrations of alkylphenols in A. oryzae arylsulfatase-treated cheese were comparable to the previously reported levels present in aged Manchego-type cheeses manufactured from pure sheep's milk. PMID:15740062

  15. Transmission characteristics and optimal diagnostic samples to detect an FMDV infection in vaccinated and non-vaccinated sheep

    NARCIS (Netherlands)

    Eble, P.L.; Orsel, K.; Kluitenberg-van Hemert, F.; Dekker, A.

    2015-01-01

    We wanted to quantify transmission of FMDV Asia-1 in sheep and to evaluate which samples would be optimal for detection of an FMDV infection in sheep. For this, we used 6 groups of 4 non-vaccinated and 6 groups of 4 vaccinated sheep. In each group 2 sheep were inoculated and contact exposed to 2 pen

  16. Phenolsulfonphthalein test in healthy sheep and in sheep with reductions in functional renal mass.

    Science.gov (United States)

    Filippich, L J; English, P B; Ainscow, J

    1985-03-01

    The phenolsulfonphthalein (PSP) plasma clearance and urinary excretion tests were applied to sheep before and after 50% and 75% reductions in functional renal mass. The PSP determinants found most useful as indicators of renal mass reduction were the 15-minute urinary excretion percentage and the 60-minute (PSP60) plasma concentration. Although both of these determinants could be used to detect renal mass reduction, the 15-minute PSP excretion percentage was the more sensitive. The PSP60 value was influenced by factors other than reduced nephron numbers; the contraction of the PSP volume of distribution that occurred after renal mass reduction was one important influencing factor. Overall, the PSP tests more accurately reflected the volume of blood delivered to the kidney than the proximal tubular secretory capacity.

  17. Initial Results from a Study of Climatic Changes and the Effect on Wild Sheep Habitat in Selected Study Areas of Alaska

    Science.gov (United States)

    Pfeifer, Edwin; Ruhlman, Jana; Middleton, Barry; Dye, Dennis; Acosta, Alex

    2010-01-01

    data bases relating to Dall sheep habitats in selected study areas. Alaska's sheep habitats are typified by long, narrow bands of mountainous uplifts generally arrayed west-to-east, and perpendicular to prevailing south-to-north weather-front movements. Classic Dall sheep habitat occurs on snow-shadowed slopes within these narrow mountainous habitats. On the basis of these data, we offer an explanatory hypothesis relating Dall sheep welfare to weather and climate-influenced nutrition and a monitoring scheme, which should produce data sufficient to test the robustness of this hypothesis. If correlated with population changes, the methods used in our comparative observations may provide long-term monitoring tools for wildlife managers and be applicable in other widely-dispersed wild sheep habitats. If no significant correlations emerge from our modeling exercises, the notion that wild sheep are a sufficiently sensitive species to be seen as an indicator species will have to be reexamined.

  18. Creutzfeldt-Jakob disease a case report, with special attention to the electroencephalogram in this disorder and to its possible relationships to kuru, scrapie and «mad cow disease»

    Directory of Open Access Journals (Sweden)

    A.H. Chapman

    1993-06-01

    Full Text Available A case of Creutzfeldt-Jakob disease in a 58-year-old Brazillian cattle rancher and businessman is presented. The EEG was normal, which is consistent with the fact that it was made during the first half of his illness; in a later stage suppression of normal rhythms by slow moderate voltage waves would be expected. The resemblances of kuru, scrapie and "mad cow disease» to C-J disease are discussed. In each of these 4 illnesses the patient or affected animal (scrapie and «mad cow disease" (a has a widespread spongiform encephalopathy and consequent dementia, myoclonic epilepsy and cerebellar and corticospinal symptoms, (b Each illness is caused by a virus (or virus-like organism called a PrP or prion which is unusually resistant to heat and entirely resistant to ultraviolet light and x-rays, (c This causative agent can be transmitted to other mammals by intracerebral injection or, in the proved cases of 3 of them, by the oral route. Unresolved questions about C-J disease include the following: Are C-J disease, kuru, scrapie and "mad cow disease" essentially similar illnesses caused by the same virus or by subtle variants of it? What is the incubation period of C-J disease, and does its virus exist for long periods of time in some asymptomatic persons, some of whom may never become neurologically ill? How does this virus enter the bodies of most persons with C-J disease, and why does the clinical disease characteristically occur only in middle age?

  19. Induction of photosensitivity in sheep with Erodium moschatum (L. L'Hérit

    Directory of Open Access Journals (Sweden)

    J.C. Stroebel

    2002-07-01

    Full Text Available Erodium moschatum is an exotic weed in the southern and southwestern coastal areas of the Western Cape Province (WCP, South Africa. It has been suspected as the cause of photosensitivity in sheep. However, attempts to induce photosensitivity by dosing it to sheep have thus far been unsuccessful. During August 1999, 2 sheep suffering from severe photosensitivity were presented for clinical examination to the Western Cape Provincial Veterinary Laboratory (WCPVL. One sheep was sacrificed for autopsy. Except for skin lesions associated with photosensitivity, no icterus or other lesions were present. Histopathological examination of affected skin revealed epidermal necrosis while the liver had no microscopic lesions. It was therefore concluded that the sheep might have been suffering from primary photosensitivity. The farmfrom which the sheep came, situated in the Malmesbury district, WCP, was visited to determine the source of the photodynamic agent. The flock from which the sheep originated had been grazing in a camp where E. moschatum was growing abundantly and had been heavily grazed. Some remaining Erodium in the camp was collected, pulped and dosed over a period of 7 days to an adult sheep. Another sheep was dosed simultaneously with Erodium growing on the premises of the WCPVL. Both sheep developed mild photosensitivity, which was confirmed by histopathological examination of skin biopsies. It was concluded that E. moschatum can induce photosensitivity (probably the primary type in sheep if ingested in large quantities.

  20. Hydrogen Beyond the Classic Approximation

    CERN Document Server

    Scivetti, I

    2003-01-01

    The classical nucleus approximation is the most frequently used approach for the resolution of problems in condensed matter physics.However, there are systems in nature where it is necessary to introduce the nuclear degrees of freedom to obtain a correct description of the properties.Examples of this, are the systems with containing hydrogen.In this work, we have studied the resolution of the quantum nuclear problem for the particular case of the water molecule.The Hartree approximation has been used, i.e. we have considered that the nuclei are distinguishable particles.In addition, we have proposed a model to solve the tunneling process, which involves the resolution of the nuclear problem for configurations of the system away from its equilibrium position