Mark D L
Am J Vet Res. 1975 Dec;36(12):1803-7.
Studies were done to determine the survival of infective Ancylostoma caninum 3rd-stage larvae on 3 ground covers commonly used in dog run construction: bare ground, pea gravel, and concrete. Changes in numbers of recovered larvae were compared to meterologic data and the most significant weather variables were determined. Larvae were recovered 1 to 7 days on bare ground. Larvae survived longer in the fecal mass (mean of 3 days) than on the bare ground (mean of 2 days). Rain was the most significant variable, in that it was positive in its effects (higher larval count) early in the experiment (causing fecal mass breakdown and release of larvae) and negative (lower larval count) later in the experiment (spreading larvae away from test site). Larvae were also recovered 1 to 7 days on pea gravel. They were recovered for a mean 2.6 days from the fecal sample, a mean of 1.5 days from the rocks directly below the fecal mass, and a mean of 1.3 days from the remaining rocks. Here also, rain was the most significant weather factor. It was negatively significant (lower larval count) for the fecal mass (spreading of the larvae) and positive for those in the pebbles (increasing the moisture in the pebbles). Survival time of larvae on concrete was shorter than that on the other 2 substrates: from 0 to 2 days. Larvae were recovered a mean of 1.3 days from the fecal mass and a mean of 0., days from the surrounding concrete. Rain was positively significant early in the experiments in that it released trapped larvae from the fecal mass. Sunlight consistently was negatively significant (lower larval count) due to its lethality to the unprotected larvae.
开展了多项研究，以确定感染性犬钩虫三期幼虫在犬舍建设中常用的三种地面覆盖物上的存活情况：裸露地面、豌豆砾石和混凝土。将回收幼虫数量的变化与气象数据进行比较，并确定最显著的天气变量。在裸露地面上1至7天可回收幼虫。幼虫在粪便团中存活的时间更长（平均3天），而在裸露地面上的存活时间较短（平均2天）。降雨是最显著的变量，在实验初期其影响为正（幼虫数量增加）（导致粪便团分解并释放幼虫），而在实验后期为负（幼虫数量减少）（将幼虫从测试地点散开）。在豌豆砾石上1至7天也可回收幼虫。从粪便样本中回收幼虫的平均时间为2.6天，从粪便团正下方的岩石中回收幼虫的平均时间为1.5天，从其余岩石中回收幼虫的平均时间为1.3天。同样，降雨也是最重要的天气因素。它对粪便团的影响为负（幼虫数量减少）（幼虫散开），而对卵石中的幼虫影响为正（增加卵石中的湿度）。幼虫在混凝土上的存活时间比在其他两种基质上短：为0至2天。从粪便团中回收幼虫的平均时间为1.3天，从周围混凝土中回收幼虫的平均时间为0. 天。降雨在实验初期影响为正，因为它从粪便团中释放出被困的幼虫。由于阳光对未受保护的幼虫具有致死性，因此其影响始终为负（幼虫数量减少）。
