Variation among faecal egg counts following natural nematode infection in Scottish Blackface lambs
Variation among faecal egg counts following natural nematode infection in Scottish Blackface lambs
复制标题
苏格兰黑脸羔羊自然线虫感染后粪便卵数的变化
DOI：
10.1017/s0031182005009029
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发表时间：
2005
期刊：
影响因子：
2.4
通讯作者：
Stewart Mitchell
中科院分区：
文献类型：
--
作者：
M. Stear;O. Abuagob;M. Benothman;S. Bishop;G. Innocent;A. Kerr;Stewart Mitchell
对苏格兰南部和中部两群自然感染的苏格兰黑脸绵羊的粪卵计数进行了检测。平均计数的分布是右偏的，类似于伽马分布。计数因月而异，平均计数从5月到7月上升，然后下降，但在10月份再次上升，尽管每年的数据并不总是显示出如此明确的模式。两个养殖场的平均产蛋量没有显著差异。卵计数方差的分布也是右偏的，符合伽玛分布。每个种群的平均值和方差之间有很强的相关性，这意味着种群间的方差变化在很大程度上反映了平均卵数的变化。平均产卵量和方差高的种群不一定有更多的成虫，但来自环斑天牛以外物种的成虫数量较多，特别是椰子虫、轴毛线虫和玻璃毛线虫。不同寄生虫种类对产卵量的贡献解释了负二项分布对羔羊粪卵计数的相对较差和不一致的拟合。
Faecal egg counts were examined in 2 flocks of naturally infected Scottish Blackface sheep in southern and central Scotland. The distribution of mean counts was right skewed and similar to a gamma distribution. The counts varied with month, with mean counts rising from May to July, then falling but rising again in October, although data within each year did not always show such a clear pattern. There was no significant difference in mean egg count between the 2 farms examined. The distribution of egg count variances was also right skewed and conformed to a gamma distribution. There was a strong relationship between the mean and the variance for each population, implying that variation among populations in variances largely mirrored variation in mean egg counts. Populations with high mean egg counts and variances did not necessarily have more adult nematodes but had a greater number of adult nematodes from species other than Teladorsagia circumcincta, particularly Cooperia spp., Trichostrongylus axei and Trichostrongylus vitrinus. The contribution of different parasite species to the egg count explains the relatively poor and inconsistent fit of the negative binomial distribution to faecal egg counts in lambs.