Rossanigo C E, Gruner L
INRA, Station de Pathologie Aviaire et de Parasitologie, Nouzilly, France.
Parasitol Res. 1996;82(4):304-11. doi: 10.1007/s004360050118.
Isolates from eight gastro-intestinal nematode species of sheep, cattle and deer parasites were maintained in sheep and faecal cultures were processed at different temperatures (for four species) and moistures (for the eight species). For all the tested species, the third-stage larvae (L3) were longer at temperatures optimal for development and their length increased linearly with faecal moisture contents (FMC). These variations in length mainly concerned the volume of intestinal cells. The length of L3 had no consequence on their survival in water at room temperature (five species tested), but the short L3 migrated more slowly on agar gel than did the longer ones (verified for three species) and exsheathed more slowly (verified for two species). The establishment rate observed for short L3 of Teladorsagia circumcincta in lambs was lower than that seen for long L3 in three other lambs, but the developed worms were similar in length and fecundity. These results are relevant to our understanding of how the different species could adapt to and/or compensate for adverse conditions of development.
从绵羊、牛和鹿的8种胃肠道线虫寄生虫分离株在绵羊体内进行培养，并在不同温度（针对4种线虫）和湿度（针对8种线虫）条件下对粪便培养物进行处理。对于所有测试的线虫种类，在发育的最佳温度下，第三期幼虫（L3）更长，并且其长度随粪便含水量（FMC）呈线性增加。这些长度变化主要涉及肠道细胞的体积。L3的长度对其在室温水中的存活没有影响（测试了5种线虫），但短L3在琼脂凝胶上的迁移速度比长L3慢（验证了3种线虫），脱鞘也更慢（验证了2种线虫）。在羔羊中观察到的环形泰勒虫短L3的定殖率低于另外三只羔羊中长L3的定殖率，但发育成熟的虫体在长度和繁殖力方面相似。这些结果有助于我们理解不同线虫种类如何适应和/或补偿不利的发育条件。
