James P J, Moon R D, Ragsdale D W
Department of Entomology, University of Minnesota, USA.
Med Vet Entomol. 1998 Jul;12(3):276-83. doi: 10.1046/j.1365-2915.1998.00110.x.
The sheep biting louse (Bovicola ovis) feeds superficially on the skin of sheep but appears to stimulate an immune response. In this study we examined the association between louse infestation and serum and skin surface antibodies. Louse numbers were monitored on experimentally infested Polypay and Columbia ewes for two years and on their lambs in the second year. Serum and skin wash samples were tested for antibodies to soluble extracts of B. ovis, Stomoxys calcitrans and Musca autumnalis by enzyme linked immunosorbent assay (ELISA). In addition, the effects of skin wash extracts on B. ovis were examined in vitro. The titre of anti-B. ovis antibodies in the serum did not differ significantly between infested and naive ewes. However, there was an increase in serum antibody titre which coincided with periods of high louse density in ewes with high louse counts. Infested lambs had higher serum antibody levels than naive lambs. Substantial cross reactivity was evident among extracts of the different insects. Densities of lice on the ewes during population decline were negatively related to the titre of skin surface antibodies. Skin washings collected from sheep during B. ovis population decline reduced the number of louse progeny when incorporated into louse diet. These results indicate that B. ovis stimulates an immune response in sheep and suggest that compounds on the skin surface may play a role in the regulation of louse populations.
羊咬虱（Bovicola ovis）在羊的皮肤表面取食，但似乎会刺激免疫反应。在本研究中，我们检测了虱感染与血清及皮肤表面抗体之间的关联。对实验感染的波利佩和哥伦比亚母羊的虱数量进行了两年监测，并在第二年对其羔羊进行了监测。通过酶联免疫吸附测定（ELISA）检测血清和皮肤冲洗样本中针对羊咬虱、厩螫蝇和秋家蝇可溶性提取物的抗体。此外，还在体外检测了皮肤冲洗提取物对羊咬虱的影响。感染组和未感染组母羊血清中抗羊咬虱抗体的滴度没有显著差异。然而，在虱数量较多的母羊中，血清抗体滴度的增加与虱密度高的时期相吻合。感染的羔羊血清抗体水平高于未感染的羔羊。不同昆虫的提取物之间存在明显的交叉反应。在虱数量下降期间，母羊身上的虱密度与皮肤表面抗体滴度呈负相关。在羊咬虱数量下降期间从羊身上收集的皮肤冲洗液加入虱的食物中后，会减少虱后代的数量。这些结果表明，羊咬虱会刺激羊的免疫反应，并表明皮肤表面的化合物可能在虱种群的调节中发挥作用。
