Mclean A R, Hoek A, Hoinville L J, Gravenor M B
lnstitute for Animal Health, Newbury, Berkshire, UK.
Proc Biol Sci. 1999 Dec 22;266(1437):2531-8. doi: 10.1098/rspb.1999.0956.
Responses to an anonymous postal survey concerning scrapie are analysed. Risk factors associated with farms that have had scrapie are identified as size, geographical region, lambing practices and holding of certain breeds. Further analysis of farms that have scrapie only in bought-in animals reveals that such farms tend to breed a smaller proportion of their replacement animals than farms without scrapie. Farms that have had scrapie in home-bred animals have attributes associated with breeding many animals: large numbers of rams bought, few ewes bought, and many animals that are home-bred. The demography of British sheep farms as described by size, breeds, purchasing behaviour, age structure and proportion of animals that are home-bred is summarized. British farms with scrapie reveal certain special features: they have more sheep that are found dead, more elderly ewes and more cases of scab.
对一份关于羊瘙痒病的匿名邮寄调查问卷的回复进行了分析。与曾发生过羊瘙痒病的农场相关的风险因素被确定为规模、地理区域、产羔方式以及某些品种的饲养情况。对仅在购入动物中出现羊瘙痒病的农场进行的进一步分析表明,与没有羊瘙痒病的农场相比,这类农场培育的替代动物比例往往较小。在自繁动物中发生过羊瘙痒病的农场具有与繁育大量动物相关的特征:购入大量公羊、购入母羊较少以及大量自繁动物。总结了按规模、品种、购买行为、年龄结构和自繁动物比例描述的英国养羊场的人口统计学特征。发生过羊瘙痒病的英国农场呈现出某些特殊特征:它们有更多被发现死亡的羊、更多老龄母羊以及更多疥癣病例。