Mavrogianni V S, Papadopoulos E, Gougoulis D A, Gallidis E, Ptochos S, Fragkou I A, Orfanou D C, Fthenakis G C
Veterinary Faculty, University of Thessaly, 43100 Karditsa, Greece.
Faculty of Veterinary Medicine, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece.
Vet Parasitol. 2017 Oct 15;245:71-77. doi: 10.1016/j.vetpar.2017.08.013. Epub 2017 Aug 24.
Objective was to study, in an experimental model, the possible role of gastrointestinal nematode infection in predisposing ewes to mastitis during the lactation period. Twenty-four ewes (A or B [n=12]), free from nematode and trematode helminths, were used. Group A animals received 5000 third-stage larvae of a trichostrongylid helminth cocktail and group B ewes were unparasitised controls. Animals in group A developed gastrointestinal trichostrongylosis confirmed by >500epg in faecal samples; mean epg of group B ewes were <20 (P<0.001). Ewes were challenged by deposition of Mannheimia haemolytica into the teat duct. In group A, 7 ewes developed clinical and 5 subclinical mastitis; no ewe in group B developed clinical mastitis, but only subclinical (12 ewes) (P=0.002). M. haemolytica was isolated from 132/132 and 121/132 udder samples from group A or B, respectively (P<0.015); increased leucocyte numbers were recorded in 66/66 and 61/66 samples, respectively (P=0.023). During post-mortem examination, mean number of helminths in gastrointestinal content was 2523 and 7.5 in group A or B, respectively (P<0.001); within group A, proportions of Teladorsagia and Haemonchus were significantly greater in ewes that developed clinical mastitis than in others which did not (0.709 and 0.162 versus 0.662 and 0.136, respectively; P<0.035). M. haemolytica was isolated from 36/36 and 19/36 udder tissue samples from group A or B, respectively (P<0.001). In ewes with subclinical mastitis (in group A or B), inducible-lymphoid-follicles were observed in the teat, which were not observed in ewes with clinical disease. Total pathology scores summed over all days were 127 and 73 for group A or B ewes, respectively (maximum possible 192; P<0.05). In general, there was positive correlation between intestinal helminth counts and pathology score (P<0.001) and between Teladorsagia counts and pathology score (P=0.002) in ewes that developed clinical mastitis. It is concluded that, in view of bacterial challenge, gastrointestinal trichostrongylosis and particularly Teladorsagia infection, might lead to clinical mastitis, through various pathogenetic pathways.
目的是在一个实验模型中研究胃肠道线虫感染在泌乳期母羊易患乳腺炎方面可能发挥的作用。使用了24只未感染线虫和吸虫的母羊（A组或B组[n = 12]）。A组动物接种了5000条毛圆科蠕虫混合的第三期幼虫，B组母羊作为未感染寄生虫的对照。A组动物粪便样本中每克粪便虫卵数（epg）>500，确诊发生了胃肠道毛圆线虫病；B组母羊的平均epg<20（P<0.001）。通过将溶血曼氏杆菌注入乳腺导管对母羊进行攻毒。A组中，7只母羊发生了临床乳腺炎，5只发生了亚临床乳腺炎；B组中没有母羊发生临床乳腺炎，只有亚临床乳腺炎（12只）（P = 0.002）。分别从A组和B组的132/132和121/132份乳腺样本中分离出溶血曼氏杆菌（P<0.015）；分别在66/66和61/66份样本中记录到白细胞数量增加（P = 0.023）。在尸检过程中，A组和B组胃肠道内容物中的蠕虫平均数量分别为2523条和7.5条（P<0.001）；在A组中，发生临床乳腺炎母羊体内的泰勒原圆线虫和血矛线虫比例显著高于未发生临床乳腺炎的母羊（分别为0.709和0.162，对比0.662和0.136；P<0.035）。分别从A组和B组的36/36和19/36份乳腺组织样本中分离出溶血曼氏杆菌（P<0.001）。在发生亚临床乳腺炎的母羊（A组或B组）中，在乳腺中观察到了诱导性淋巴滤泡，而在发生临床疾病的母羊中未观察到。A组和B组母羊所有天数的总病理评分分别为127分和73分（最高可能为192分；P<0.05）。总体而言，发生临床乳腺炎的母羊中，肠道蠕虫计数与病理评分之间呈正相关（P<0.001）；泰勒原圆线虫计数与病理评分之间也呈正相关（P = 0.002）。结论是，鉴于细菌攻毒，胃肠道毛圆线虫病，尤其是泰勒原圆线虫感染，可能通过多种致病途径导致临床乳腺炎。
