Vaughn Ashlee A, Delbarco-Trillo Javier, Ferkin Michael H
Department of Biological Sciences, The University of Memphis, Ellington Hall, Memphis TN 38152, USA.
Ethology. 2012 Dec 1;118(12):1133-1139. doi: 10.1111/eth.12016. Epub 2012 Sep 24.
An individual's nutritional status affects the manner in which same- and opposite-sex conspecifics respond to that individual, which may affect their fitness. Male meadow voles, Microtus pennsylvanicus, increase their sperm allocation if they encounter the scent mark of an unfamiliar male that is not nutritionally challenged. If, however, the scent mark comes from a male that has been food deprived for 24 hours, stud male voles do not increase their sperm allocation. Food deprived males may be viewed as being lower quality and a reduced risk of sperm competition by rival males. We hypothesized that stud males in promiscuous mating systems tailor their sperm allocations depending on whether rival males have been food deprived and then re-fed. We predicted that newly re-fed males will be considered a strong risk of sperm competition because of the potentially high fitness and survival costs associated with food deprivation in males, and that they will cause stud males to increase their sperm allocation. Our results, however, showed that the recovery period from 24 hours of food deprivation was a relatively slow process. It took between 96 hours and 336 hours of re-feeding male scent donors that were food deprived for 24 hours to induce stud males to increase their sperm allocation to levels comparable to when scent donors were not food deprived. Stud male voles may be conserving the amount of sperm allocated until the male scent donors have recovered from food deprivation and subsequent re-feeding.
个体的营养状况会影响同性和异性同种个体对该个体的反应方式，这可能会影响它们的健康状况。雄性草甸田鼠（Microtus pennsylvanicus）如果遇到未受营养挑战的陌生雄性的气味标记，会增加精子分配量。然而，如果气味标记来自一只已被剥夺食物24小时的雄性，种公田鼠则不会增加精子分配量。被剥夺食物的雄性可能被视为质量较低，竞争对手雄性认为与之精子竞争的风险降低。我们假设，在滥交交配系统中的种公田鼠会根据竞争对手雄性是否被剥夺食物然后重新喂食来调整它们的精子分配。我们预测，新重新喂食的雄性会被认为是精子竞争的强大风险，因为雄性食物剥夺可能伴随着潜在的高健康和生存成本，并且它们会导致种公田鼠增加精子分配量。然而，我们的结果表明，从24小时食物剥夺中的恢复期是一个相对缓慢的过程。对被剥夺食物24小时的雄性气味供体重新喂食96小时至336小时，才能诱使种公田鼠将精子分配量增加到与气味供体未被剥夺食物时相当的水平。种公田鼠可能会保留精子分配量，直到雄性气味供体从食物剥夺和随后的重新喂食中恢复过来。
