Search

Inbreeding in a small population of Chios sheep undergoing intense selection for the PrP gene was assessed 10 years after the beginning of a scrapie resistance selection programme. Inbreeding in this stock, already under selection for production traits, was analysed by using pedigree records containing 10,492 animals from 1968 to 2008, and also by genotyping 192 individuals with a panel of 15 microsatellites. Genetic markers indicated a loss of heterozygosity (FIS over all loci was 0.059) and allelic diversity (mean effective number of alleles was 3.075±0.275). The annual rate of inbreeding increased significantly after the start of the scrapie resistance programme, ΔF=0.005 compared with ΔF=0.001 before 1999, and was subjected to several genetic bottlenecks, mainly due to the low initial frequency of resistant animals. However, the mean individual inbreeding coefficient estimated from the pedigree - in this closed stock resembling the case of a rare breed - stood at the level of 4.5 per cent, five generations after the implementation of selection for the PrP gene. The inbreeding coefficient estimated by genetic markers was 4.37 per cent, implying that such a marker panel could be a useful and cost-effective tool for estimating inbreeding in unrecorded populations. [ABSTRACT FROM AUTHOR]

The article offers information on the disease surveillance report for July 2014 from SAC Consulting Veterinary Services. It discusses reports about border disease outbreak which led to continuing sheep losses in cattle industry. Other information such as porcine reproductive and respiratory virus and swine influenza virus in pigs as well as transport-associated acetonaemia in dairy heifers is presented. INSET: Review of bovine respiratory disease.

The article presents disease surveillance report from Scottish Agricultural College Consulting: Veterinary Services (SAC C VS) for September 2011. Perth diagnosed chondrodystrophy having concurrent dystocia alterations in an Aberdeen Angus cross calf. Edinburgh diagnosed metaldehyde poisoning in dairy heifer died in a group that run with a bull. Diagnoses of louping ill are linked with tick activity in cattle that mostly peak in the autumn.

Reports of clinical scrapie in Great Britain between January 1, 1993 and December 31, 2002 were reviewed. Scrapie was confirmed in 4142 sheep on 1099 holdings. the cumulative case and holding incidence risks decreased in 2001, probably owing to the outbreak of foot-and-mouth disease, although there were regional variations. Sheep aged between three and four years old constituted the largest affected group. In the period between 1998 and 2002, 51-3 per cent of the cases had the genotype ARQ/VRQ, 19-3 per cent were ARQ/ARQ and 18-9 per cent were VRQ/VRQ; Swaledale, Shetland and Welsh mountain sheep were the most common pure breeds reported. The areas at highest risk were the Shetland Islands, followed by the south and east of England. [ABSTRACT FROM AUTHOR]

The Cheviot flock at the Institute for Animal Health's Neuropathogenesis Unit (NPU) has endemic scrapie, which affects primarily VRO/VRQ sheep and at high frequency. A new flock with a full range of PrP genotypes, including the highly susceptible VRO/VRQ has been produced on a separate site, from animals in the NPU breeding flock, and it remains scrapie-free after eight years. In contrast, in a parallel flock at the NPU farm, scrapie has reappeared after five years, although the animals were kept in separate accommodation from the scrapie-affected sheep. During this time the NPU breeding flock continued to have scrapie cases. Although it is known that highly susceptible sheep can remain free of infection in a clean environment, this is the first report of the infection being removed successfully from the bloodlines of scrapie-affected sheep. The results confirm that scrapie is not a genetic disease dependent only on the PrP gene sequence, but requires both genetic susceptibility and an infectious agent. [ABSTRACT FROM AUTHOR]

An anonymous postal survey was conducted in 2002 to estimate the proportion of farms in Great Britain affected with scrapie and to gather information on the likely risk factors for the occurrence of the disease; the response rate was 53 per cent. The survey showed that 1 per cent of the respondents thought they had had scrapie in their flock in the previous 12 months, and that 12 per cent thought they had had scrapie in the past. The results of the survey were consistent with the results of a similar survey carried out in 1998, and with notification patterns, but in 1998 approximately 3 per cent of farmers reported having had scrapie in the previous 12 months. It is not clear whether the apparent decrease in the prevalence of scrapie is real or whether it may be due to factors such as sampling biases, or to the increasing knowledge of the signs of scrapie shown by the respondents in 2002. [ABSTRACT FROM AUTHOR]

Samples of tissue from the central nervous system (CNS), the lymphoreticular system (LRS) and the rectal mucosa of a large number of scrapie-exposed sheep, with and without signs of clinical disease, were examined immunohistochemically for evidence of disease-associated prion protein (PrPd). The rectal mucosa has received almost no attention so far in scrapie diagnosis, despite its abundant rectoanal mucosa-associated lymphoid tissue, and its accessibility. The scrapie-confirmed cases included 244 with clinical disease, of which 237 (97.1 per cent) were positive in the rectal mucosa, and 121 apparently healthy sheep, of which 104 (86 per cent) were positive in the rectal mucosa. PrPd was detected in 86.4 to 91.5 per cent of the other IRS tissues of the healthy sheep examined and in 77.7 per cent of their CNS tissues. The stage of infection, therefore, affected the probability of a positive result in the rectal mucosa, whereas the breed, PrP genotype, age and sex had little or no independent effect. Accumulations of PrPd were observed in the rectal mucosa and other IRS tissues of VROJARR sheep with preclinical and clinical scrapie, albeit with a lower frequency and magnitude than in sheep of other PrP genotypes. Western immunoblotting analyses of samples of rectal mucosa gave the characteristic PrP glycoprofile, with a sensitivity similar to that of immunohistochemistry. [ABSTRACT FROM AUTHOR]

In February 2003, a postal survey of 1279 sheep farmers in the Shetland Islands yielded 586 responses (46 per cent response rate). The principal aim of the survey was to gather information on the history and control of scrapie. Overall, 28.5 per cent of the respondents thought they had had a case of scrapie in their flock at some time. There was a slow increase in the proportion of affected flocks during the 1970s, followed by a more rapid increase during the 1980s and early 1990s, and a decline from the mid-1990s onwards. The peak proportion of affected flocks was approximately 6 per cent in 1994. Of the farmers who had ever had scrapie in their flock, 97.1 per cent had attempted to control the disease. The most common method of control was breeding from non-susceptible tups, used by 90.6 per cent of the affected flocks and 75.1 per cent of the flocks that had never been affected. A comparison of the characteristics of the affected and unaffected flocks indicated that an increased risk of scrapie was associated with the larger flocks, the open flocks and the flocks that bought in lambs. The basic reproduction ratio for the spread of scrapie between flocks was estimated to be 1.47, and the mean duration of an outbreak within a flock was estimated to be approximately two years. [ABSTRACT FROM AUTHOR]

Between 1997 and March 2004, the nervous form, or visna, of maedi-visna infection was diagnosed in 71 of 1631 sheep (4.35 per cent) examined in the Castilla y León region of Spain, of which 634 had shown nervous signs. The presence of the virus was confirmed by immunohistochemistry and in some cases by PCR on frozen-thawed or paraffin-embedded tissue samples. The main clinical signs were hindleg ataxia and paresis, but blindness or nystagmus were also observed. Thirty-three of the affected sheep (46.5 per cent) were two years old or younger. The affected sheep showed variable degrees of a non-suppurative meningoencephalitis, and immunohistochemistry identified positive cells in all cases, with no relation to the intensity of the inflammatory lesion. [ABSTRACT FROM AUTHOR]

Prion protein (PrP) genotype data from statutory confirmed cases and from three non-case datasets have been used to calculate the odds ratio (OR) for the development of clinical scrapie for an individual sheep of a given PrP genotype, compared with one possessing the ‘wild-type’ ARQ/ARQ genotype. Logistic regression has been used to estimate the ORS, and a multiple-test procedure has been used to evaluate the statistical significance of each comparison. The results are similar to those observed in other studies: the VRQ/VRQ genotype has OR point estimates greater than 20; the ARQ/VRQ and ARH/VRQ genotypes have OR point estimates between 5 and 20; AHQ/VRQ between 0.03 and 0.1; ARR/VRQ 0.4 and 0.5; all the other PrP genotypes, excluding ARR/ARR, ARR/ARH and AHQ/ARH for which no clinical cases have been recorded have OR point estimates of less than 0.3. The estimates derived from each dataset are comparable, but not identical. This can be explained by plausible biases inherent in the sampling of the non-case populations. [ABSTRACT FROM AUTHOR]

Between July and September 2002 there were outbreaks of bluetongue on three sheep holdings in the communities of San Gregorio Magno (Salerno, Campania), Laviano (Salerno, Campania) and Carpino (Foggia, Puglia), and the involvement of bluetongue virus (BTV) was confirmed serologically and virologically. The mortality rate was at least 11 per cent and involved BTV serotype 2 (ETV-2) and serotype 9 (BTV-9). These holdings were also surveyed for the Culicoides (Diptera: Ceratopogonidae) vectors; approximately 10,000 midges belonging to 15 species were captured, but they did not include a single specimen of the classical Afro-Asiatic bluetongue vector, Culicoides imicola. Species belonging to the Obsoletus complex dominated the light-trap collections, and Culicoides obsoletus Meigen, Culicoides scoticus Downes and Kettle and Culicoides clewulfi Goetghebuer constituted 90 per cent of all the Culicoides species captured. Fifty-six pools of the Obsoletus complex (excluding C dewulfi), each containing 100 individual midges and containing only porous and gravid females, were assayed for virus. BTV-2 was isolated from three pools from San Gregorio Magno and Carpino, and BTV-9 was isolated from one pool from Laviano. These results indicate that a species other than C imicola is involved in the current re-emergence of bluetongue in the Mediterranean Basin, but whether it is C obsoletus sensu stricto or C scoticus, or both, is uncertain. [ABSTRACT FROM AUTHOR]

• Seasonal increase in the incidence of louping ill in sheep • Acidosis in cattle and sheep • Salmonella Dublin enteritis and abortion in cattle • Fasciolosis in sheep • Streptococcus suis in pigs • Fowl cholera in turkeys • Yersiniosis in red deer [ABSTRACT FROM AUTHOR]

An enteric disease characterised by diarrhoea and illthrift affected 12 of a flock of 700 six- to 12-month-old ewe lambs in Cornwall between December 1996 and September 1997. The affected lambs were undersized, became thin and suffered an unremitting diarrhoea until they died. The illness lasted for three to 14 days, although, with hindsight the owner considered that the lambs had been below average size before the enteric signs developed. The outbreak ceased only as a result of the dispersal sale of the flock as breeding ewes. The flock had been purchased from different sources, but 11 of the cases occurred in a group of 40 purchased from one source. Postmortem, the alimentary changes resembled mucosal disease in cattle, and immunostaining of histological sections of the affected tissues revealed pestiviral antigen. Non-cytopathic pestiviruses were isolated from the lesions of two of the affected lambs and from the blood of several clinically normal ewe lambs from the same group. All the pestivirus isolates were typed as Border disease virus. [ABSTRACT FROM AUTHOR]

Discusses the number of outbreaks of louping ill in sheep in south-west and northern Scotland. Association of autumn tick activity with the outbreaks of louping ill in sheep flocks; Diagnosis of selenium deficiency; Identification of acute copper poisoning as the cause of sudden death in a newly purchased Texel tup.

The article offers information pertaining to transmissible spongiform encephalopathies (TSEs). Result of a study shows that few or no histological lesions in the retinas of sheep affected with scrapie, however, morphological changes in specific retinal types have been demonstrated. Moreover, it mentions that the effect of TSE on retinal function in a scrapie-infected Suffolk sheep through the use of flash electroretinography needs further investigation.

The article investigates the presence of susceptible alleles on sheep and the possibility of the sheep's breed to be exposed to scrapie, an infectious disease classified as a transmissible spongiform encephalopathy member. Results of the study concerning the genotype of the sheep are presented in figures collaborating the sheep's genotype and its significance on the effect of scrapie susceptibility. Farmers have assessed whether they judged scrapie-susceptible sheep to be of higher quality.

Maedi-visna (MV0) infection was detected in a cohort of 68 purchased ewes, one of several groups of sheep introduced to a farm after the previous stock had been culled with suspected foot-and-mouth disease in 2001. Except for short periods totalling six to seven weeks when the sheep co-grazed with 13 ewe lambs and ram lambs, the infected cohort was kept separate from other sheep on the farm over a total of 21 months. During this period two crops of lambs were reared from the infected ewes. All the lambs were fattened and killed, and all ewes were culled after the second crop of lambs had been weaned. Subsequent serological testing of the remaining sheep on the farm confirmed the elimination of MV infection from the flock, leading to its acceptance in the Maedi Visna Accreditation Scheme of the Scottish Agricultural College's Sheep and Goat Health Schemes. [ABSTRACT FROM AUTHOR]

Examines the enzootic intranasal tumor virus infection in sheep in Japan. Description of the disease; Detection of seromucinous nasal exudate in a ewe; Conduct of an examination of the affected ewe; Application of reverse transcriptase polymerase chain reaction to nasal swabs to investigate the prevalence of the disease among sheep flocks.

Describes a study to characterize the clinical features observed in sheep naturally affected with scrapie in Aragon, Spain, and to compare the results with previously described findings. Alternation of mental status; Excitatory signs such as restlessness, anxiety and a tendency to avoid restraint; Alteration of superficial sensitivity which was characterized by hypoesthesia or total anesthesia at the distal extremes of the hindlimbs.

Investigates the PrP genotypes of scrapie-affected sheep of several breeds in Spain. Examination of the distributions of different PrP genotypes within the Spanish sheep breeds; Determination of the allelic frequencies for scrapie-related alleles in scrapie-affected animals; Association of the VRQ allele with the susceptibility of sheep to scrapie.

The article presents research that examines the effect of border disease virus (BVD) acute infections on lambs in commercial feedlots. The study shows the association of BDV infection to production performance decrease. It notes the observance of respiratory and diarrhoea signs in lambs, but not any signs of disease. It concludes that BDV transmission and its effects on the lamb's growth and health simulate BVD virus action in feedlot calves.

The article offers the authors' insights on the results of their study on Schmallenberg virus (SBV) transmission. They say that blood samples were obtained from female sheep and submitted for testing, which used quantitative reverse transcription-polymerized chain reaction (qRT-PCR) for SBV RNA and indirect enzyme-linked-immunosorbent serologic assay (iELISA) for immunoglobulin G (IgG) antibody. They discuss the implications of the positive results for antigen and antibody.

The article describes the analysis of prion protein (PrP) gene (PRNP) variation in Moroccan sheep breeds to determine its susceptibility to scrapie. In the study, the amino acid variations were analyzed at codon 136, 154 and 171, which have been shown to be particularly important in genetic susceptibility studies of many sheep breeds in other countries. Results demonstrates PRNP polymorphisms and indicates that the Moroccan sheep have a high genetic susceptibility to scrapie.

The article describes a clinical case of Nor98-like sheep scrapie that occurred in Great Britain in 1989. According to the authors, neuropathological changes indicative of scrapie were seen predominantly in the cerebellum and consisted of a pronounced vacuolar degeneration of both the molecular and granular layers, accompanied by an abnormal accumulation of host gene encoding PrP. They add that Nor98 may have been present but not identified in certain genotypes of sheep for many years.

The article discusses the prion disease, called scrapie, a disease of sheep and goats which is characterized by the accumulation of pathologically folded prion protein (PrP). Scrapie has been detected in Hampshire Down and Suffolk sheep in Brazil since the late 1970s. This study, which evaluates on the PrP genotypes of sheeps in the country, has concluded that almost half of the animals could be classified as being potentially susceptible to scrapie.

The article discusses the study of genotyping for cellular prion protein gene polymorphisms in sheeps in Greece. Scrapie is a communicable and fatal disease that affects the nervous system of sheeps and prion proteins. It has not been found in rare Greek breeds and its apparent resistance to genotypes was determined. To conform with the Greek surveillance program, farms that are infected with scrapie will be checked and sheeps without allele will be stamped out.

The article discusses the results of a study which examined the lateral transmission of natural scrapie to scrapie-free New Zealand sheep placed in an endemically infected flock in Great Britain. The study found that the New Zealand sheep with specific PrP genotypes contracted natural scrapie. Natural scrapie can pass between sheep after birth.

The article discusses the results of surveys that estimates the prevalence of scrapie in the sheep population in Great Britain in 2002 and 2003. The surveys reported a number of sheep found dead-on-farm in the region. There were several examinations for scrapie-associated fibrils and the Western blot.

Describes the clinical, histopathological and virological investigation of an outbreak of peste des petits ruminants (PPR) that occurred in a sheep and goat flock in Kayseri, Turkey. Clinical signs observe in sheep's and goats with PPR infection; Examinations taken on the animals; Physical description of goats and sheep's with PPR infection.

Studies scrapie in sheep by researchers from Great Britain. Etiology and epidemiology; Symptoms and diagnosis; Significance of the study on the development of novel approaches in treating the disease.

Reports on the outbreak of the viral disease Peste des petits ruminants that affects goats and sheeps in Western Turkey. Occurrence of the viral disease in other countries; Classification of the family and genus of the virus; Percentage rate of the virus-affected districts and regions in the country; Indications of the viral presence in animal; Experimentation of the oral swabs and labial biopsy taken from the animals.

Reports on presentation made by Dr. Paul Webb of the Veterinary Laboratories Agency which discussed atypical cases of scrapie found in 2003 as part of the British program of active surveillance of sheep slaughter population. Staining pattern yielded from investigations with a panel of antibodies which were different from classical scrapie.

Discusses a case of scrapie similar to Nor98 diagnosed in Belgium via active surveillance. Histopathological investigation; Terms of the surveillance protocol; Questions concerning the scrapie active epidemiosurveillance protocol; Implications for veterinary medicine.

Discusses cases of scrapie resembling Nor98 from an Irish flock. Assessment of the vacuolation of the grey matter neuropil; Detection of the granular staining in the frontal cortex and basal ganglion; Single nucleotide polymorphisms at codons 136, 154 and 171 in the muscle tissue; Different route of entry of the scrapie agent.

Focuses on the identification of the prevalence and distribution of scrapie in sheep flocks in Ireland. Use of a postal questionnaire survey to collect information on scrapie from a large number of flock owners; Assessment of the farmer's knowledge and previous experience of scrapie; Presentation of the results of the study; Aim of the study to determine the prevalence of scrapie in the country.

Reports on the discovery of an unusual scrapie case in sheep in Great Britain. Investigation conducted by the Veterinary Laboratories Agency; Findings suggesting that the scrapie does not resemble previously recognized type of scrapie or experimental bovine spongiform encephalopathy in sheep.

Summarizes results of a postal survey done on 2002 in Great Britain aimed at assessing farmers' experience scrapie or transmissible spongiform encelopathy in sheep flocks. Percentage of farmers confirming at least one case of scrapie; Usefulness of the postal survey method in gathering considerable amounts of data.

The article reports on the actions made by the Food and Agriculture Organization of the United Nations (FAO) in response to the livestock epidemic in the Democratic Republic of the Congo (DRC) in 2012. It says that the FAO launched an emergency project to provide vaccines to 500,000 sheep and goats in the country's unaffected areas. It notes that tens of thousands of goats were affected by peste des petits ruminants (PPR) and 75,000 of animals were reported dead.

The article reports on the confirmation of the Animal Health and Veterinary Laboratories Agency (AHVLA) regarding a case of Schmallenberg virus (SBV) on a sheep farm in Cornwall, England.

The article presents abstracts on veterinary topics which include the impacts of transport factors regarding the morbidity and mortality in pigs for slaughter, teicoplanin injection for intramammary infection treatment in sheep and computer keyboards bacterial contamination in practice consulting clinics.

The article reports on the compulsory vaccination campaign against the bluetongue disease on cattle and sheep in Scotland. Cabinet secretary for rural affairs Richard Lochhead claims that 70% of eligible susceptible animals have been vaccinated with over 5.5 million doses of bluetongue vaccine. He reminds farmers that vaccination against the bluetongue virus is a requirement in the country and urges farmers to take precautions against the virus.

The article highlights the results of a study of atypical scrapie in a sheep in Scotland. It describes the first clinical case of atypical scrapie to be found in a sheep in the country. The article reports on the death of a four-year-old Cheviot ewe in a flock with no history of scrapie. The study was conducted by Dr. Mark Dagleish and colleagues.

The article reports that suspect clinical cases related to scrapie from 1993 to 2002 were recorded on a database in Great Britain. The cumulative incidence of cases increased in 2001 in association with the foot-and-mouth disease epidemic. Swaledale, Shetland, Suffolk cross and Welsh mountain sheep were affected.

The article focuses on the detection of atypical scrapie in a sheep from a flock considered to be free from transmissible spongiform encephalopathies, according to the Great Britain Department for Environment, Food and Rural Affairs (DEFRA). The flock is maintained by DEFRA under strict biosecurity conditions. Routine tests are conducted when animals die or are culled from the flock.

The article presents abstracts of veterinary medicine research. They include "Brucellosis in Northern Ireland, 1990 to 2000," "Causes of Death in a Colony of Captive Maras," and "Farmers' Assessments of Scrapie-Susceptible Sheep."

The article reports on the impact of farmers' poor compliance with statutory notification on monitoring the prevalence of scrapie in the sheep population in Great Britain. Based on a survey conducted, scrapie was associated with larger flocks and flocks that lambed in group pens. Scrapie cases were also associated with brought-in sheep.

The article overviews the survey on the incidence of scrapie of sheep farmers in Shetland, Scotland. The author stressed that the high incidence is manifestly related to the intensification of the sheep farming, which occurred in the year 1970s through the 90s. The survey revealed that increased risk in scrapie was connected with larger flock sizes, open flocks and flocks that bought in lambs.

The article reports on the high prevalence of maedi-visna disease, the nervous form of the viral disease in sheep in Spain. A study conducted confirmed the virus infection in sheep using techniques like immunohistochemistry, enzyme-linked immunosorbent assay and polymerase chain reaction. The possible reasons for the high number of cases of visna are neutrotopic strains of the virus, breed susceptibility and farming practices.

The article describes the results of surveys carried out in 2002 and 2003 that records the prevalence of scrapie in sheep in Great Britain. In the surveys, their were a number of scrapie positive dead-on-farm sheep in the region.