This study was conducted to investigate potential interactions between the abomasal blood feeder Haemonchus contortus and the intestinal mucosal browser Trichostrongylus colubriformis among deliberately infected Boer goats. Faecal and blood samples were collected twice a week for eight weeks from 25 parasite-naïve goats. Correlation analysis and multiple linear regression models were conducted to explore the association between phenotypic variables and variables taken at necropsy. Positive associations were identified between total FEC and log T. colubriformis number (r = 0.62, p < 0.05) as well as between IgA and peripheral eosinophil counts (r = 0.65, p < 0.05). A negative correlation was observed between T. colubriformis and log H. contortus number (r=-0.56, p < 0.05). Multiple linear regression models show that H. contortus and T. colubriformis interacted with each other. T. colubriformis appeared to contribute more significantly to the variation of FEC than H. contortus. Co-infection induced an IgA response which was only effective against T. colubriformis but not protective against H. contortus infection. This could be seen via significant associations of IgA with both nematode species but with the effect of IgA differing for H. contortus and T. colubriformis. In this study, H. contortus infection was not detrimental to the goats with no observed impact on PCV. This could be because the growth of T. colubriformis as represented by its length was associated with reduced number and composite burden of H. contortus during co-infection, or possibly due to low infection dosage. Improved understanding of the impact of H. contortus and T. colubriformis and their interaction from natural co-infection studies is beneficial for a better understanding of the goat-parasite interaction and its potential impacts on the health and productivity of animals.

本研究旨在调查故意感染的波尔山羊中，皱缩血矛线虫和肠粘膜浏览器蛇形毛圆线虫之间的潜在相互作用。为期八周，每周两次从 25 只未感染寄生虫的山羊身上采集粪便和血液样本。进行相关分析和多元线性回归模型来探讨表型变量与尸检变量之间的关联。总 FEC 与蛇形毛虫数之间存在正相关（r = 0.62，p < 0.05），IgA 与外周嗜酸性粒细胞计数之间也存在正相关（r = 0.65，p < 0.05）。蛇形线虫和捻转线虫数之间存在负相关（r=-0.56，p < 0.05）。多元线性回归模型表明， H. contortus和T. colubriformis之间存在相互作用。 T. colubriformis似乎比H. contortus对 FEC 的变化有更显着的贡献。共感染诱导 IgA 反应，该反应仅对蛇形毛虫有效，但对捻转毛虫感染没有保护作用。这可以通过 IgA 与两种线虫物种的显着关联看出，但 IgA 对捻转线虫和蛇形线虫的影响不同。在这项研究中， H. contortus感染对山羊没有损害，也没有观察到对 PCV 的影响。这可能是因为以长度为代表的蛇形毛虫的生长与蛇形毛虫数量和复合负担的减少有关。 合并感染期间出现扭转，或可能是由于感染剂量低所致。通过自然共感染研究加深对捻转扭伤线虫和蛇形线虫的影响及其相互作用的了解，有利于更好地了解山羊寄生虫相互作用及其对动物健康和生产力的潜在影响。