Houdijk J G M, Kyriazakis I, Jackson F, Huntley J F, Coop R L
Animal Nutrition and Health Department, Scottish Agricultural College, West Mains Road, Edinburgh, EH9 3JG, UK.
Vet Parasitol. 2005 Apr 20;129(1-2):105-17. doi: 10.1016/j.vetpar.2004.12.023.
The effects of protein supply and reproductive status on circulating antibody responses and local inflammatory cell counts were investigated in parasitized sheep, with local immune responses assessed through a recently refined abomasal cannulation methodology. We hypothesized that if breakdown of immunity has a nutritional basis, then protein scarcity would result in a breakdown of immunity to Teladorsagia circumcincta in both periparturient and non-reproducing (barren) ewes. Twin-bearing and barren, abomasally cannulated ewes were fed at either 0.8 or 1.3 times protein requirements from 3 weeks before until 6 weeks after parturition (n = 6). All sheep were trickle infected at a rate of 10,000 infective larvae (L3) per day, for 3 days per week throughout the experiment. Faecal egg counts remained virtually zero in all barren ewes, whilst protein supplementation reduced faecal egg counts in the periparturient ewes during most of the periparturient period. Final worm burdens, taken at 6 weeks into lactation, were lower for the barren ewes than for the lactating ewes, whilst protein supplementation reduced worm burdens in the latter. Protein supply did not affect mucosal mast cell counts, which were consistently higher for the barren ewes than the periparturient ewes, but were temporarily decreased around parturition. Barren ewes and protein supplemented lactating ewes had higher globule leukocyte counts than the unsupplemented lactating ewes. Protein supplementation increased eosinophil counts in the lactating ewes though only during the later part of the lactation period. Plasma IgA anti-L3 antibody was similar for all ewes, but IgE anti-L3 antibody was higher for the protein supplemented periparturient ewes compared to the unsupplemented periparturient ewes and all barren ewes. It is likely that the combination of low protein requirements and large body protein reserves did not result in breakdown of immunity to T. circumcincta for the barren ewes. These results suggest that changes in mucosal mast cell and eosinophil counts are not necessarily associated with changes in host resistance to T. circumcincta. However, the data support the view that increased globule leukocyte counts and plasma IgE anti-L3 antibody may be associated with nutritionally improved expression of immunity in periparturient ewes.
在受寄生虫感染的绵羊中，研究了蛋白质供应和繁殖状态对循环抗体反应及局部炎症细胞计数的影响，并通过最近改进的皱胃插管方法评估局部免疫反应。我们假设，如果免疫功能的破坏有营养基础，那么蛋白质缺乏将导致围产期和非繁殖期（不育）母羊对环形泰勒虫的免疫功能破坏。从分娩前3周直到分娩后6周，对怀有双胞胎和不育的、已进行皱胃插管的母羊按照蛋白质需求量的0.8倍或1.3倍进行饲喂（n = 6）。在整个实验过程中，所有绵羊每周按每天10,000条感染性幼虫（L3）的速率连续感染3天。所有不育母羊的粪卵计数几乎为零，而蛋白质补充在围产期的大部分时间内降低了围产期母羊的粪卵计数。泌乳6周时的最终蠕虫负荷，不育母羊低于泌乳母羊，而蛋白质补充降低了后者的蠕虫负荷。蛋白质供应不影响黏膜肥大细胞计数，不育母羊的黏膜肥大细胞计数始终高于围产期母羊，但在分娩前后暂时下降。不育母羊和补充蛋白质的泌乳母羊的球状白细胞计数高于未补充蛋白质的泌乳母羊。蛋白质补充增加了泌乳母羊的嗜酸性粒细胞计数，但仅在泌乳后期。所有母羊的血浆IgA抗L3抗体相似，但与未补充蛋白质的围产期母羊和所有不育母羊相比，补充蛋白质的围产期母羊的IgE抗L3抗体更高。可能是低蛋白质需求和大量机体蛋白质储备的组合并未导致不育母羊对环形泰勒虫的免疫功能破坏。这些结果表明，黏膜肥大细胞和嗜酸性粒细胞计数的变化不一定与宿主对环形泰勒虫的抵抗力变化相关。然而，数据支持这样的观点，即球状白细胞计数增加和血浆IgE抗L3抗体可能与围产期母羊营养改善后的免疫表达有关。
