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1.
Helen L. Orbell John S. Munday Geoffrey M. B. Orbell Craig E. Griffin 《Veterinary dermatology》2020,31(5):401-403
A 12‐year‐old spayed English pointer dog developed multiple skin lesions including pigmented viral plaques, basal cell carcinomas, squamous cell carcinomas and trichoblastomas. Canine papillomavirus type 3 was detected in multiple lesions suggesting common aetiology.
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研究目的确定妊娠母羊日粮中添加长链脂肪酸(n-3)鱼油,以及维生素E是否会改变羊的初生行为。将Twin-(n=36)和triplet-(n=12)的妊娠103d的母羊分成4组.4种日粮处理.包括2种脂肪资源[Megalac,棕桐油提取物或鱼油混合物,20:5(n-3)和22:6(n-3)],2种维生素E浓度(50或500mg/kg)进行2×2设计。饲喂鱼油妊娠期延长2d,初生羊血浆中22:6(n-3)的比例增加5.1-fold.大脑中的比例增加10%,而大脑中的20:5(n-3)的比例增加5%。母羊饲喂鱼油而不是Megalac时,日粮高浓度的维生素E缩短羔羊站立的潜在期.而添加鱼油同样缩短出生至哺乳之间的时间43至34min。添加鱼油可降低初乳分泌率(ml/h)和脂肪及蛋白质的产量(g/h)。我们得出以下结论:母羊日粮添加鱼油可缩短出生至哺乳的时间,延长妊娠期,并且初生大脑中22:6(n-3):20:4(n-6)的比率增加,同时能提高羔羊存活率。但是如何减少鱼油给初乳产量带来的负面影响有待进一步的研究。 相似文献
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Two experiments were carried out to examine the nitrogenous changes occurring in herbage during harvesting and ensiling. In the first, ryegrass-clover was wilted rapidly in the laboratory (6 h) and in the field under good (48 h) and poor (48 h and 144 h) weather conditions. Protein breakdown and ammonia formation were negligible in herbage wilted rapidly and it was only when the crop was exposed to a prolonged wilt in humid conditions that appreciable proteolysis occurred. In the second experiment ryegrass-clover was ensiled in laboratory silos after treatment with varying levels of formic and sulphuric acids. An additional treatment included herbage inoculated with a mixture of lactic acid bacteria and glucose. The silos were opened after 4 and 50 d and samples were analysed for protein-N, ammonia-N, water-soluble carbohydrates and organic acids. There was a high negative correlation between level of addition of either acid and the degree of proteolysis and deamination. Even at the highest levels of formic acid (7·7 g per kg) and sulphuric acid (4·0 g per kg) additions, however, about 45% of the original herbage protein was degraded after 50 d in the silo. The inoculum treatment was also effective in reducing proteolysis, the effect after 50 d being comparable with formic acid applied at a rate of 4·1 g per kg. 相似文献
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A series of trials was conducted to compare the digestibility of organic matter in castrated male sheep and non-lactating and lactating cows given diets containing lucerne cobs. Similar digestibility coefficients were determined when sheep and non-lactating cows were given hay and lucerne cobs, but lactating cows digested diets of hay, lucerne cobs and concentrates less well than sheep. It is concluded that if sheep are used in digestibility trials with diets containing processed lucerne and concentrates intended for milking cows, appreciable errors of prediction of digestibility of organic matter may arise. 相似文献