State-of-the-art review of goat TSE in the European Union, with special emphasis on PRNP genetics and epidemiology     

Gabriele Vaccari  Cynthia H. Panagiotidis  Cristina Acin  Simone Peletto  Francis Barillet  Pierluigi Acutis  Alex Bossers  Jan Langeveld  Lucien van Keulen  Theodoros Sklaviadis  Juan J. Badiola  Olivier Andr��oletti  Martin H. Groschup  Umberto Agrimi  James Foster    Wilfred Goldmann 《Veterinary research》2009,40(5)

Scrapie is a fatal, neurodegenerative disease of sheep and goats. It is also the earliest known member in the family of diseases classified as transmissible spongiform encephalopathies (TSE) or prion diseases, which includes Creutzfeldt-Jakob disease in humans, bovine spongiform encephalopathy (BSE), and chronic wasting disease in cervids. The recent revelation of naturally occurring BSE in a goat has brought the issue of TSE in goats to the attention of the public. In contrast to scrapie, BSE presents a proven risk to humans. The risk of goat BSE, however, is difficult to evaluate, as our knowledge of TSE in goats is limited. Natural caprine scrapie has been discovered throughout Europe, with reported cases generally being greatest in countries with the highest goat populations. As with sheep scrapie, susceptibility and incubation period duration of goat scrapie are most likely controlled by the prion protein (PrP) gene (PRNP). Like the PRNP of sheep, the caprine PRNP shows significantly greater variability than that of cattle and humans. Although PRNP variability in goats differs from that observed in sheep, the two species share several identical alleles. Moreover, while the ARR allele associated with enhancing resistance in sheep is not present in the goat PRNP, there is evidence for the existence of other PrP variants related to resistance. This review presents the current knowledge of the epidemiology of caprine scrapie within the major European goat populations, and compiles the current data on genetic variability of PRNP.  相似文献   

Reply     

Alex Dugdale  Nicki Grint  & John Burford 《The Journal of small animal practice》2009,50(7):378-379

  相似文献   

Statistical analysis of the effect of multi-stage hot drawing on the thermal shrinkage and crystallographic order of biodegradable aliphatic-aromatic co-polyester fibres     

Basel Younes  Alex Fotheringham  Robert Mather 《Fibers and Polymers》2011,12(6):778-788

Using statistical experimental design, the effects of multi-stage hot drawing process on thermal shrinkage and crystallographic order of linear aliphatic-aromatic co-polyester fibres were statistically analyzed. Thermal shrinkage and fullwidth half-maximum (FWHM) of an X-ray scattering profile of the fibres have been quantitatively assessed, and the direction of increasing or decreasing the significant process parameters has been characterized. It has been found that the number of drawing stages, drawing temperature and relaxing stage ratio affect the shrinkage and crystallographic order together. Plate temperature and the interaction between drawing stages and drawing temperature or drawing ratio have an effect on thermal shrinkage; Spin finish application and relaxing temperature have an effect on crystallographic order. The data analysis has been characterized with regard to the relationship between the studied factors statistically analyzed and the scientific reasons suggested. Factorial statistical analysis simulates the combination of drawing process parameters and the selected as-spun environmentally friendly biodegradable fibre.  相似文献   

Impact of three silvicultural treatments on growth,light-energy processing,and related needle-level adaptive traits of Pinus strobus from two regions     

John E. Major  Alex MosselerDebby C. Barsi  Britt Corriveau-DupuisMoira Campbell 《Forest Ecology and Management》2009

Our goal was to quantify and compare the impact of three silvicultural treatments (STs) on growth, light-energy processing, and needle-level morphological adaptive traits for eastern white pine (Pinus strobus L.) from large, central Ontario (ON) and small, isolated Newfoundland (NL) populations. The interest in STs is to reduce weevil (Pissodes strobi) incidence; however, there are potential adaptive changes and productivity trade-offs. The light levels for the STs were, on average, 100%, 42.0%, and 20.4% transmittance for the full-sun, and intermediate- and high-shade STs, respectively. After 8 years, overall height growth was 4.10, 3.25, and 1.70 m for full-sun, and intermediate- and high-shade STs, respectively (P < 0.001). Across all STs, ON populations had greater total height (14%), basal diameter (12%), current leader length (25%), and tree volume (49%) than NL populations (all P < 0.001). At low light levels (10 and 25 μmol m⁻² s⁻¹), high-shade ST trees had higher photochemical quenching (qP) and lower chlorophyll fluorescence (F_pc) compared with intermediate-shade and full-sun STs. At 100 μmol m⁻² s⁻¹ and beyond, full-sun ST trees had higher qP and lower F_pc than intermediate- and high-shade STs. Average total chlorophyll concentration (CHL) and content (CHLC), and carotenoid concentration (CAR), increased in response to the intermediate-shade ST but did not respond further, or decreased in the high-shade ST. Region was significant for CHL, CAR, chlorophyll a:b and CHL:CAR ratios and CHLC, with ON greater than NL, but was reversed for CHL:CAR ratio. Tree height and volume showed a curvilinear and linear relationship to light level, respectively. Tree height showed a positive linear relationship to qP, apparent photosynthesis, chlorophyll a:b ratio, and needle N (all P < 0.001). Tree height showed a negative linear relationship to F_pc, CHL:CAR ratio, specific needle area, C:N ratio, and needle area N⁻¹ (all P < 0.001). There were modest trade-offs between weevil protection and productivity in the intermediate ST due to the compensatory physiological and morphological adaptations to the limiting light, however, the trade-off with growth at the high-shade level was severe. For NL, consideration should now be given to the introduction and mixing of seed from local seed sources with more southern mainland seed sources, which would decrease the inbreeding effect and provide wider variation for natural selection for a more fit future population.  相似文献   

Liming as an ameliorator of copper toxicity in black oat (Avena strigosa Schreb.)     

Vítor Gabriel Ambrosini  Daniel José Rosa  Alex Basso  Marcelo Borghezan  Rosete Pescador  Alcione Miotto 《Journal of plant nutrition》2017,40(3):404-416

This study aimed to assess the effect of liming as an ameliorator of copper (Cu) toxicity in black oats (Avena strigosa Schreb.) grown in soil with a sandy texture. The treatments were soil supplementation with increasing doses of lime (0.0, 0.5 and 1.0 g kg^?1) and two of Cu (0 and 50 mg kg^?1). Pre-germinated black oat seeds were sown for 30 days in the soil, subsequently, the plant height, root and shoot dry mass and concentration of total chlorophyll, chlorophylls a and b, carotenoids and total soluble carbohydrates and starch were analyzed. The dose of 50 mg kg^?1 soil Cu caused a toxic effect on black oat plant growth and development, affected the internal distribution of nutrients, decreased the leaf chlorophyll concentration and increased the leaf concentration of total soluble carbohydrates and starch. Increasing lime doses ameliorated the toxic effects of Cu.  相似文献   

Investigating the impact of innate dexterity skills and visuospatial aptitude on the performance of baseline laparoscopic skills in veterinary students          下载免费PDF全文

Mathew R. A. MacCormick  Jessica J. Kilkenny MSc  Meagan Walker BSc  Alex zur Linden DVM  DACVR  Ameet Singh DVM  DVSc  DACVS 《Veterinary surgery : VS》2017,46(8):1175-1186

  相似文献   

Evidence for a collective intelligence factor in the performance of human groups   总被引：2，自引：0，他引：2  

Woolley AW  Chabris CF  Pentland A  Hashmi N  Malone TW 《Science (New York, N.Y.)》2010,330(6004):686-688

Psychologists have repeatedly shown that a single statistical factor--often called "general intelligence"--emerges from the correlations among people's performance on a wide variety of cognitive tasks. But no one has systematically examined whether a similar kind of "collective intelligence" exists for groups of people. In two studies with 699 people, working in groups of two to five, we find converging evidence of a general collective intelligence factor that explains a group's performance on a wide variety of tasks. This "c factor" is not strongly correlated with the average or maximum individual intelligence of group members but is correlated with the average social sensitivity of group members, the equality in distribution of conversational turn-taking, and the proportion of females in the group.  相似文献   

Virulence-associated trimeric autotransporters of Haemophilus parasuis are antigenic proteins expressed in vivo   总被引：1，自引：0，他引：1  

Alex Olvera  Sonia Pina  Marta P��rez-Sim��  Simone Oliveira    Albert Bensaid 《Veterinary research》2010,41(3)

Glässer’s disease is a re-emerging swine disease characterized by a severe septicaemia. Vaccination has been widely used to control the disease, although there is a lack of extended cross-protection. Trimeric autotransporters, a family of surface exposed proteins implicated in host-pathogen interactions, are good vaccine candidates. Members of this family have been described in Haemophilus parasuis and designated as virulence-associated trimeric autotransporters (VtaA). In this work, we produced 15 recombinant VtaA passenger domains and looked for the presence of antibodies directed against them in immune sera by immunoblotting. After infection with a subclinical dose of H. parasuis Nagasaki, an IgG mediated antibody response against 6 (VtaA1, 5, 6, 8, 9 and 10) of the 13 VtaA of the Nagasaki strain was detected, indicating that they are expressed in vivo. IgA production against VtaA was detected in only one animal. VtaA were more likely to be late antigens when compared to early (Omp P5 and Omp P6) and late (YaeT) defined antigens. Antibody cross-reaction with two orthologs of Nagasaki’s VtaA5 and 6, VtaA15 and 16 of strain HP1319, was also detected. No antibodies against VtaA were detected in the sera of animals immunized with a bacterin of the Nagasaki strain, suggesting poor expression in the in vitro conditions used. Taken together, these results indicate that VtaA are good candidate immunogens that could be used to improve H. parasuis vaccines. However, their capacity to confer protective immunity needs to be further studied.  相似文献   

Plasma protein electrophoresis of Trachemys scripta and Iguana iguana     

Mercè Giménez  Yolanda Saco  Raquel Pato  Alex Busquets  Jaime M. Martorell  Anna Bassols 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2010,39(2):227-235

  相似文献   

Motor laterality in 4 breeds of dog     

Paul D. McGreevy  Alex Brueckner  Peter C. Thomson  Nicholas J. Branson 《Journal of Veterinary Behavior: Clinical Applications and Research》2010,5(6):318-323

The aim of the current study was designed to explore possible breed differences in a basic behavioral phenotype in dogs. It measured paw use during food-retrieval from a cylindrical, hollow, rubber toy to assess motor laterality (pawedness) in 4 breeds of dogs selected for their morphological differences: 45 greyhounds (males n = 23/females n = 22), 47 whippets (15/32), 46 pugs (15/31), and 45 boxers (17/28). A laterality index was calculated from the use of individual paws to restrain the toy during feeding. An association was found between sex and the laterality index (P = 0.035), reflecting a significant bias for left-paw use by entire male dogs and right-paw use by entire female dogs but no sex difference was found in the mean strength of laterality. No significant association was found between age and the laterality index. No breed difference was found in the laterality index (P = 0.423) or the absolute strength of laterality (i.e., the laterality index without direction, P = 0.259). However, important breed differences in the use of the test device emerged. The frequency of simultaneous use of both paws was lowest in pugs (P < 0.0001). In addition, both brachycephalic breeds (pugs and boxers) took less time than the dolichocephalic breeds (the whippets and greyhounds) to complete the criteria of 100 paw-use scores that was set for the laterality test. The absence of breed differences in the laterality index for paw use suggests that the task is a reliable measure of motor laterality in dogs during a food-retrieval task.  相似文献