Besier R B, Dunsmore J D
Regional Veterinary Laboratory, Department of Agriculture, Albany, Australia.
Vet Parasitol. 1993 Jan;45(3-4):275-92. doi: 10.1016/0304-4017(93)90082-x.
The seasonal pattern of development of Haemonchus contortus eggs to infective larvae was investigated on the south coast of Western Australia. Sheep faeces containing H. contortus eggs were deposited on pasture plots at intervals over a 3-year period, and pasture grass and faeces were sampled periodically for infective larvae (L3). The maximum recoveries occurred in late autumn and in late spring, when adequate moisture coincided with warm temperatures. Larval development was low and sporadic over the hot and dry summer period, and depressed during winter, although most egg depositions in winter yielded L3 at some time. The proportion of L3 recovered was related to temperature and moisture parameters, and the major constraint appeared to be the availability of moisture at pasture level. The best indicator of the suitability of conditions for the development of H. contortus was the proportion of green pasture material present, based on a visual assessment.
在西澳大利亚州的南海岸，对捻转血矛线虫虫卵发育至感染性幼虫的季节性模式进行了研究。在三年时间里，每隔一段时间将含有捻转血矛线虫虫卵的羊粪便放置在牧场地块上，并定期对牧场草和粪便进行采样以检测感染性幼虫（L3）。最大回收率出现在秋末和春末，此时充足的水分与温暖的温度同时出现。在炎热干燥的夏季，幼虫发育水平较低且不连续，在冬季则受到抑制，尽管冬季大多数粪便沉积在某个时候都会产生L3。回收的L3比例与温度和湿度参数有关，主要限制因素似乎是牧场层面的水分供应。根据视觉评估，绿色牧场材料的比例是捻转血矛线虫发育适宜条件的最佳指标。
