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JT SEAMAN WS TURVEY SJ OTTAWAY AR GILMOUR RJ DIXON† 《Australian veterinary journal》1989,66(9):279-285
A field grazing trial was undertaken to monitor the health and production of crossbred sheep grazing pasture where Echium plantagineum constituted a considerable proportion of the available forage. The trial, conducted for 19 months over successive grazing seasons, demonstrated a significant difference in production, with sheep on the E. plantagineum pasture being lighter and growing less wool compared with sheep on Echium-free pasture. No mortalities involving pyrrolizidine alkaloid poisoning were recorded in sheep grazing E. plantagineum, although there was histological evidence of moderately severe liver damage associated with high liver copper concentrations in at least one sheep following the grazing of large quantities of the plant. 相似文献
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Premature farrowings caused by feeding cottonseed meal 总被引:1,自引:0,他引:1
Increasing the level of cottonseed meal (CSM) in sow diets from less than 5% to 10% increased the incidence of premature farrowings (gestation length less than 111 days) from 1.1% to 2.7% (p less than 0.001) and reduced the mean gestation length from 114.07 +/- 1.53 to 113.70 +/- 1.59 days (p less than 0.0001). Survival of piglets born prematurely was poor. After removal of CSM from the diet there was a residual effect lasting several weeks before the gestation length returned to normal. Experimental feeding of diets containing 20% and 40% CSM to small groups of sows caused significant shortening of gestation length and 3 of 26 sows fed 40% CSM farrowed prematurely. The mechanism by which CSM causes this effect has yet to be determined. 相似文献
86.
D S Hall J F Amann G M Constantinescu D W Vogt 《Journal of the American Veterinary Medical Association》1987,191(9):1113-1115
Congenital anury (taillessness) was observed in 2 Cairn Terriers. Fecal staining of the hind limbs was evident in both dogs. A mating of the affected dogs produced a litter of 2 apparently normal pups. The small litter size may have been attributable to lethal gene combinations similar to those described in mice. The radiographic appearance of the caudal and sacral vertebrae was atypical in both tailless dogs. Results of myelography and electrodiagnostic testing of anal sphincter function were normal in one of the dogs. One of the tailless dogs was euthanatized and was found to lack specific muscles and muscle parts responsible for normal defecation, which resulted in fecal staining of the hind limbs. Pedigree analysis revealed the tailless dogs to be closely related and slightly inbred, suggesting a hereditary etiologic factor for anury. 相似文献
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D W Vogt T A Gipson B Akremi S Dover M R Ellersieck 《American journal of veterinary research》1984,45(11):2408-2409
Data on 4,411 male and 4,148 female progeny from the University of Missouri-Columbia swine research herd were analyzed to evaluate the associations of sire, breed, weight at birth, and sex of the pigs with the development of congenital splayleg. Statistically significant differences in frequency of splayleg were found among sires and among breeds indicating a genetic influence. Differences in frequencies among male vs female progeny also were found to be statistically significant. The overall frequency among male progeny was 1.74 times that observed among female progeny. Comparison of birth weights of splayleg vs normal pigs showed birth weights to be statistically significantly smaller among affected pigs. 相似文献
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