<?xml version="1.0" encoding="UTF-8"?><xml><records><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Rothschild,Miriam</style></author><author><style face="normal" font="default" size="100%">Ford,Bob</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Does a pheromone-like factor from the nestling rabbit stimulate impregnation and maturation of the rabbit flea?</style></title><secondary-title><style face="normal" font="default" size="100%">Nature</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Beziehung zum Wirt</style></keyword><keyword><style  face="normal" font="default" size="100%">biology</style></keyword><keyword><style  face="normal" font="default" size="100%">development</style></keyword><keyword><style  face="normal" font="default" size="100%">Troester</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">1969</style></year><pub-dates><date><style  face="normal" font="default" size="100%">1969</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">221</style></volume><pages><style face="normal" font="default" size="100%">1169 - 1170</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">&lt;p&gt;As it had been observed that rabbit fleas (Spilopsyllus cuniculi (Dale)) seemed to mature faster when the nestling rabbits on which they fed [cf. RAE B 55 767, etc.] were in large litters rather than small ones, the possible existence of an environmental or pheromone-like ` nestling factor &amp;#39; was investigated. In two experiments, fleas that had been kept on a buck rabbit and showed no signs of maturation were placed in transparent observation boxes with controlled temperature and humidity. In the first experiment, 50 fleas (both sexes included) were released simultaneously on to a day-old rabbit confined alone in a box and on to five other siblings from the same litter confined together in another box. In the second experiment, 50 fleas of each sex were released simultaneously on to a single day-old rabbit confined alone in a box and on to a single sibling rabbit from the same litter surrounded by 3-5 other siblings but separated from them by butter-muslin partitions, which allowed air to circulate throughout the box above lie muslin stalls in which rabbits and fleas were confined. In the two experiments, fresh day-old nestlings were substituted for the original ones after 12 and 24 hr., respectively. Random samples of fleas from each box were removed at fixed intervals, killed and sectioned. Very little difference between boxes was apparent after 12-24 hr. After 48 hr., 75% of female fleas feeding in boxes containing several nestlings, but only 29% of those on solitary nestlings, had been impregnated, and 65% of the former and 32% of the latter contained yolk-laden eggs, and 35 and 11% respectively, contained chorionated eggs. These findings support the impression that fleas mature more rapidly on large litters than on small ones and that a &amp;#39;nestling factor &amp;#39;, perhaps acting merely by stimulating the fleas&amp;#39; appetites, may be involved. It is also possible that a solitary nestling may be more restless than one with companions and that the normal feeding and copulation pattern of its fleas may be correspondingly disturbed or modified.&lt;/p&gt;
</style></abstract><issue><style face="normal" font="default" size="100%">5186</style></issue><notes><style face="normal" font="default" size="100%">758</style></notes></record></records></xml>