蚤类在宿主体表的分布及温度和蚤数的关系

THE DISTRIBUTION OF FLEAS ON THE HOST BODY IN RELATION TO TEMPERATURE AND THE NUMBER OF FLEAS

本文研究了方形黄鼠蚤松江亚种Citellophilus tesquorum sungaris和二齿新蚤Neopsylla bidentatiformis在小白鼠体表的分布及环境温度和体表蚤数的关系。结果证明,在各种温度下,鼠背部蚤数均多于腹部。5℃时,鼠前部蚤数多于后部;10—20℃时,前部与后部蚤数相近;25—40℃时,后部蚤数多于前部。鼠后背部蚤数随温度升高而增多,前腹部蚤数随温度升高而减少;温度越高二者之差越大,说明温度越高蚤越向后背部集中。鼠体蚤数较少时,背部与腹部,前部与后部,蚤数差别明显;鼠体蚤数过多时,各部位蚤数无大差别。

Experiments were carried out on the distribution of Citellophilus lesquorum sungaris and Neopsylla bidentatiformis on the bodies of their hosts in relation to ambient temperature and the number of fleas. The results are as follows.1. At all temperatures in the experiments more fleas were found on the dorsal side of the host body when the number of fleas was low. At 5℃ the number of fleas in the anterior area of the host body was greater than that in the posterior area; at 10-20℃ the anterior and posterior areas harboured fleas nearly in equal number, but at 25-40℃ more fleas were found in.the anterior area.2. Linear correlations have been found between temperature and the number of fleas in the anterior or posterior areas of the host body. The correlation is positive in the posterior dorsal area but negative in the anterior ventral area.3. When the total number of fleas on the host body was low conspicuous difference in distribution appeared between the dorsal and ventral sides and between the anterior and posterior areas. This difference would disappear when the number of the fleas was great. No difference was found between the two species of fleas tested in the experiments.