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101.
SUMMARY The epidemiological, clinical and pathological features of a disease syndrome in adult cattle grazing woolly-pod vetch (Vicia villosa ssp dasycarpa) or popany vetch (V benghalensis) are reported. Outbreaks of toxlcosis occurred between midwinter and midsummer in 3 dairy and 6 beef herds on the north coast of New South Wales, between 1982 and 1992. Friesian, Angus, Murray Grey, Guernsey and Hereford breeds were affected. Mean morbidity and case fatality rates in affected herds were 7% (65 of 889) and 69%, respectively. Signs of pruritic dermatitis, illthrift and death were associated with an eosinophilic granulomatous inflammation of many organs, particularly involving the renal cortex, dermis, myocardium, adrenal glands, lymph nodes and hepatic portal triads.  相似文献   
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Objective To investigate the seroprevalence of equine herpesvirus 1 in foals around weaning and after weaning on two large Thoroughbred farms using a type-specific enzyme-linked immunosorbent assay to determine exposure to infection.
Design A longitudinal population study in groups of Thoroughbred weanling foals.
Study population Two hundred weanling Thoroughbred foals from a population of about 380 foals were enrolled on two adjacent stud farms in the Hunter Valley of New South Wales. Foals on both farms were weaned from February to May 1995 into randomly selected groups of 10 to 15 foals. Farms were selected because of their willingness to cooperate in the survey and because their detailed records of foals and their movements. They were representative of well-managed large Thoroughbred stud farms in New South Wales. Both studs had upper respiratory tract disease among weanling foals around weaning each year although the sero-prevalence of viral respiratory disease on either farm was not known before the study.
Procedure Serum was collected from foals within each group at fortnightly intervals from 9th February until 1st June 1995, and at a single follow-up period in August 1995. Each sample was tested in triplicate using an antibody-detection ELISA which is type-specific for EHV-1 and EHV-4 antibodies.
Results and conclusions There was serological evidence of EHV-1 infection both before and after weaning. The prevalence of EHV-1 antibody in the sample population increased during the study and individual cases of EHV-1 infection were identified. The increase was caused both by the seroconversion of foals within the groups and by the recruitment into the study of foals with pre-existing EHV-1 antibody. Evidence of EHV-1 infection in Thoroughbred foals after weaning has not been reported previously in Australia and this has implications for vaccination regimens.  相似文献   
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During 2004, a survey of Mycobacterium avium subspecies paratuberculosis (map) was conducted in 101 randomly selected dairy herds to investigate associations between the infection status of the herds, different management practices, and possible disease indicators, such as indices of mastitis and reproductive performance. Data were collected by means of a questionnaire through personal interviews with the farmers and veterinarians in charge of each farm. At the same time, blood samples were taken from cattle over one year old and analysed with a commercial elisa to detect antibodies to map. Statistical analyses indicated that the following management practices constituted major risk factors: utilisation of colostrum from cows with a previous positive map diagnosis, and housing replacement calves with adult cattle before they were six months old. Seropositivity to map was related to the herds' bulk tank somatic cell counts and incidence of clinical mastitis, but not to their reproductive performance.  相似文献   
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This study was undertaken to characterize and establish the kinematic standards of Italian standardbred trotter horses in real racing conditions. Certain parameters, such as the angles of both front and hind fetlock joints, stride length, stride frequency and average speed in youngs and adults are presented, examinated and compared with statistical tests. The angles and stride length were obtained using ONTRACK software over frames extracted from two CANON MV630i digital videocameras. For the stride frequency, a third identical videocamera filmed the horses to count the number of beats per minute. The average speed was calculated by multiplying the stride frequency by the stride length and transforming the result into kilometers per hour. The data reveal that as speed increases, younger horses have more extended fetlock joints than adults. Contrary to this, at the maximum speed (hereafter referred to as sprint speed) the adults increase both their stride frequency and stride length, while young horses increase stride frequency and decrease stride length. We think that the knowledge of these parameters in competition breeds could have potential relevance as they may reveal early indicators of the development of proper and adequate characteristics in young horses of those breeds.  相似文献   
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