Deem S L, Donachie P L, Norval R A, Mahan S M
University of Florida/USAID/SADC Heartwater Research Project, Veterinary Research Laboratory, Harare, Zimbabwe.
Vet Parasitol. 1996 Jan;61(1-2):133-44. doi: 10.1016/0304-4017(95)00820-9.
Two studies were carried out to determine whether colostrum from dams living in a heartwater-endemic area has an influence on calfhood immunity to Cowdria ruminantium infection. The initial study was conducted using Friesian calves originating from a heartwater-free herd. Experimental groups consisted of calves receiving colostrum from dams living in a heartwater-endemic area and known to be exposed to C. ruminantium (as determined by the indirect fluorescent antibody test) and calves receiving colostrum from dams located in a heartwater-free area. All calves were challenged at 3 days of age with a homologous C. ruminantium blood stabilate originating from the same area as the endemic colostrum. A significant difference in both the intensity of clinical reactions and percentage of fatal heartwater cases was noted between the two groups of calves. Three of the five calves receiving the colostrum free of C. ruminantium-specific antibodies succumbed to challenge, whereas none of the five calves receiving the colostrum from the heartwater-endemic area showed any clinical reactions. A second similar study was carried out using 12 mixed breed calves born in a heartwater-endemic area of Zimbabwe. The results from this study supported the findings of the first. The significant role of colostrum in calfhood immunity to C. ruminantium infection is discussed in relation to the epidemiology and control of heartwater.
开展了两项研究，以确定生活在牛心水病流行地区的母畜初乳是否对犊牛期抵抗反刍兽考德里氏体感染的免疫力有影响。最初的研究使用的是来自无牛心水病畜群的弗里斯兰犊牛。实验组包括接受来自生活在牛心水病流行地区且已知接触过反刍兽考德里氏体（通过间接荧光抗体试验确定）的母畜的初乳的犊牛，以及接受来自无牛心水病地区的母畜的初乳的犊牛。所有犊牛在3日龄时用与地方性初乳来自同一地区的同源反刍兽考德里氏体血液稳定株进行攻毒。两组犊牛在临床反应强度和致命性牛心水病例百分比方面均存在显著差异。接受不含反刍兽考德里氏体特异性抗体的初乳的5头犊牛中有3头死于攻毒，而接受来自牛心水病流行地区的初乳的5头犊牛均未出现任何临床反应。第二项类似研究使用了在津巴布韦牛心水病流行地区出生的12头杂种犊牛。该研究结果支持了第一项研究的结果。结合牛心水病的流行病学和防控，讨论了初乳在犊牛期抵抗反刍兽考德里氏体感染的免疫力中的重要作用。
