Philpott M
Avoncroft Cattle Breeders Ltd, Sugarbrook, Stoke Prior, Bromsgrove, Worcestershire.
Br Vet J. 1993 Jul-Aug;149(4):339-69. doi: 10.1016/S0007-1935(05)80075-2.
This review summarizes the major infectious diseases of the three major agricultural species (cattle, sheep and pigs) and horses, and presents the evidence for and against the possibility of infectious agents being transmitted between animals via the venereal route or by the use of semen or early embryos in commercial artificial insemination (AI) or embryo transfer (ET). Cattle feature most prominently in the widespread distribution of frozen semen, and national and international organizations have set out guidelines to work towards disease-free bull studs with semen free from potential pathogens. With the control of major epizootic diseases, attention has been focused on such diseases as IBR, BVD and blue tongue, where clinical signs are rarely evident but the detection of virus in semen is of great importance. New information on the relevance of bacterial disease such as Mycobacterium paratuberculosis, campylobacteriosis and leptospirosis is reviewed, along with details of the mycoplasma and ureaplasma species of the bull's genital tract. Bovine spongiform encephalopathy (BSE) has attracted much research and semen is not regarded as a source of infection. New work on the pathogenesis of a number of diseases and the use of new biotechnology in diagnosis is included. The International Embryo Transfer Society (IETS) has encouraged a great deal of experimental work--much originating in Canada--on the risk of transmission of disease from donors to recipients via a 7-day-old blastocyst. There has been much success in demonstrating that with an approved protocol of handling the embryos, to date there is very little danger in disease transmission with both viruses and bacteria. The mycoplasma group appear more intractable and the role of BSE is still being evaluated. In sheep, scrapie, Brucella ovis infection and blue tongue feature in current work. In the pig there is a surge in international movement of pig semen, and Aujeszky's disease and the new so-called Blue Ear disease feature prominently. Much work is in progress on infectious agents likely to be found in the semen of stallions, with an expanding trade in the international movement of chilled and frozen semen. Equine embryo transfer experiments are hampered by the very limited number of embryos available. Reference is also made to the further risk of disease transmission by in vitro manipulated embryos.
本综述总结了三种主要农业养殖动物（牛、羊和猪）以及马的主要传染病，并阐述了支持和反对传染病病原体通过性传播途径，或在商业人工授精（AI）或胚胎移植（ET）中使用精液或早期胚胎在动物之间传播的证据。牛在冷冻精液的广泛应用中最为突出，国家和国际组织已制定准则，致力于建立无病公牛站，确保精液无潜在病原体。随着主要动物疫病的控制，人们的注意力已集中在诸如传染性牛鼻气管炎（IBR）、牛病毒性腹泻（BVD）和蓝舌病等疾病上，这些疾病临床症状很少明显，但精液中病毒的检测非常重要。本文综述了诸如副结核分枝杆菌、弯曲杆菌病和钩端螺旋体病等细菌性疾病相关性的新信息，以及公牛生殖道支原体和脲原体种类的详细情况。牛海绵状脑病（BSE）已引发大量研究，精液不被视为感染源。文中还纳入了一些疾病发病机制的新研究以及新生物技术在诊断中的应用。国际胚胎移植协会（IETS）鼓励了大量实验工作——其中许多起源于加拿大——研究疾病通过7日龄囊胚从供体传播给受体的风险。已成功证明，通过批准的胚胎处理方案，迄今为止，病毒和细菌传播疾病的风险非常小。支原体组似乎更难处理，疯牛病的作用仍在评估中。在绵羊方面，当前的研究涉及羊瘙痒病、绵羊布鲁氏菌感染和蓝舌病。在猪方面，猪精液的国际流动激增，奥耶斯基氏病和新出现的所谓蓝耳病尤为突出。关于种马精液中可能发现的传染因子的研究正在大量进行，冷冻和冷藏精液的国际交易量不断扩大。马胚胎移植实验因可用胚胎数量非常有限而受阻。文中还提到了体外操作胚胎传播疾病的进一步风险。
