Matjila P T, Penzhorn B L
Faculty of Veterinary Science, Department of Veterinary Tropical Diseases, University of Pretoria, Private Bag X04, 0110, Onderstepoort, South Africa.
Vet Parasitol. 2002 Mar 1;104(2):93-102. doi: 10.1016/s0304-4017(01)00605-7.
Information on the occurrence and diversity of coccidia infecting cattle in different farming systems in South Africa is lacking. The objective of the study was to determine the levels of infection of coccidia in cattle at three localities and to determine the Eimeria species occurring at each locality. Faecal samples (n=1936) were collected over a 13-month period from a dairy farm (Mallesons), a Bonsmara breeding farm (Kaalplaas) and a Nguni stud farm (Pienaars River). Samples were collected from adults >24 months old and calves <12 months old. The modified McMaster technique was used to determine OPG (oocysts per gram) of faeces. Samples with OPGs > or =2000 were allowed to sporulate in potassium dichromate solution at room temperature. Species identification was done by measurement and morphological characteristic of each species. At Mallesons, 29% of samples were positive, at Kaalplaas 50% and at Pienaars River 52%. The most prevalent species were Eimeria zuernii and E. ellipsoidalis at Mallesons, E. zuernii and E. bovis at Kaalplaas and E. bovis and E. zuernii at Pienaars River, respectively. Adults had very low OPGs. There was a pattern at the three localities in that high OPGs were only recorded in calves, which were also shedding the most pathogenic species.
南非不同养殖系统中感染牛的球虫的发生情况和多样性信息匮乏。本研究的目的是确定三个地点牛的球虫感染水平,并确定每个地点出现的艾美耳球虫种类。在13个月的时间里,从一个奶牛场(马勒森斯)、一个邦斯马勒肉牛养殖场(卡尔普拉斯)和一个恩古尼种马场(皮纳尔斯河)采集了粪便样本(n = 1936)。样本取自年龄大于24个月的成年牛和年龄小于12个月的犊牛。采用改良的麦克马斯特技术测定粪便中的每克卵囊数(OPG)。OPG大于或等于2000的样本在室温下于重铬酸钾溶液中进行孢子化处理。通过测量每个种类的形态特征进行种类鉴定。在马勒森斯,29%的样本呈阳性,在卡尔普拉斯为50%,在皮纳尔斯河为52%。在马勒森斯最常见的种类是邱氏艾美耳球虫和椭圆艾美耳球虫,在卡尔普拉斯是邱氏艾美耳球虫和牛艾美耳球虫,在皮纳尔斯河是牛艾美耳球虫和邱氏艾美耳球虫。成年牛的OPG非常低。在这三个地点呈现出一种模式,即高OPG仅在犊牛中记录到,而犊牛也排出致病性最强的种类。