Altaif K I, Al-Abbassy S N, Abboud H B
Parasitology. 1980 Apr;80(2):233-40. doi: 10.1017/s0031182000000706.
The response of Awassi sheep to primary infection with 10 000 Haemonchus contortus larvae and subsequent challenge with 20 000 larvae was studied. Two types of response to re-infection were observed. The first, characterized by a sharp decline in egg counts, progressive improvement in packed cell volume (PCV) and a marked loss of adult worms and challenge larvae, was considered as self-cure and protection. In the second type of response there was a temporary decline in egg counts, no improvement in PCV and necropsy findings indicated hyper-infection with challenge larvae.
研究了阿瓦西羊对初次感染10000条捻转血矛线虫幼虫以及随后再次感染20000条幼虫的反应。观察到了对再次感染的两种反应类型。第一种表现为虫卵计数急剧下降、红细胞压积（PCV）逐渐改善以及成虫和感染幼虫显著减少，被视为自愈和保护。第二种反应类型表现为虫卵计数暂时下降、PCV无改善，尸检结果表明感染幼虫导致超感染。
