McGuire B
Department of Biological Sciences, Smith College, Northampton, Massachusetts 01063, USA.
J Comp Psychol. 2001 Dec;115(4):439-43.
Prairie vole pups (Microtus ochrogaster) in laboratory cages prefer hind nipples. In this research, the author observed 8 litters of prairie voles in a seminatural environment to confirm the preference for hind nipples and to determine if young on hind nipples were groomed more frequently or dislodged less frequently than were young on other nipples. Prairie vole pups in seminatural environments preferred hind nipples; this preference was illustrated by the progressive use of more anterior nipples only as litter size increased and by the reluctance of pups to voluntarily release their hold on hind nipples. Maternal grooming of young did not vary with suckling location. Prairie vole young on hind nipples, however, were dislodged less frequently than were young on other nipples. Less frequent dislodgment from hind nipples during maternal movements may play a role in the preference for hind nipples in prairie voles.
实验室笼子里的草原田鼠幼崽（橙腹草原田鼠）更喜欢后乳头。在这项研究中，作者在半自然环境中观察了8窝草原田鼠，以确认对后乳头的偏好，并确定后乳头上的幼崽是否比其他乳头上的幼崽得到更频繁的梳理或被挤下的频率更低。半自然环境中的草原田鼠幼崽更喜欢后乳头；随着窝仔数增加，更多地逐渐使用靠前的乳头，以及幼崽不愿主动松开对后乳头的抓握，都表明了这种偏好。母鼠对幼崽的梳理并不随哺乳位置而变化。然而，后乳头上的草原田鼠幼崽被挤下的频率比其他乳头上的幼崽更低。母鼠移动时后乳头被挤下的频率较低，这可能在草原田鼠对后乳头的偏好中起作用。
