Smith T E, Faulkes C G, Abbott D H
Nebraska Behavioral Biology Group, Department of Psychology, University of Nebraska, Omaha 68182, USA.
Horm Behav. 1997 Jun;31(3):277-88. doi: 10.1006/hbeh.1997.1384.
The study investigated the role of odor cues from two naked mole-rat colonies, in conjunction with behavioral cues from nonbreeding colony members, in maintaining suppression of ovulation in subordinate female naked mole-rats isolated from the two parent colonies. Four high ranking nonbreeding female naked mole-rats were removed from their respective parent colonies and singly housed in separate burrow systems. For a 64-day period, the removed females were maintained in daily odor contact with their parent colony by daily rotating soiled bedding material between the parent colony and the burrow systems of removed females. In addition, subsets of nonbreeding animals from the respective parent colony were regularly moved into the burrow systems of removed females for 2-day periods during this 64-day period. Removed females were therefore in continual social contact with subsets of parent colony animals except for the breeding pair. All four removed females exhibited raised levels of urinary progesterone (< 2 ng/mg Cr) indicative of the onset of ovarian function within 3 days of being separated from the parent colony. Removed females exhibited a normal ovulatory cycle with levels of progesterone remaining elevated for 25-35 days (mean concentration of progesterone +/- SEM; 16.2 +/- 2 ng/mg Cr). Initiation of aggression and sexual behavior by removed females increased significantly when they were isolated from the parent colony. The results demonstrated that odor cues from the complete colony in conjunction with behavioral/tactile/vocal cues from the nonbreeding colony members were not the major cues maintaining reproductive suppression in nonbreeding female naked mole-rats. Instead, our results suggest that female reproductive suppression in naked mole-rats is caused by a dominance-related behavioral mechanism requiring direct contact with the breeding female.
该研究调查了来自两个裸鼹鼠群体的气味线索，以及来自非繁殖群体成员的行为线索，在维持从两个亲代群体中分离出来的从属雌性裸鼹鼠排卵抑制方面所起的作用。从各自的亲代群体中取出四只高等级的非繁殖雌性裸鼹鼠，并将它们单独安置在不同的洞穴系统中。在64天的时间里，通过每天在亲代群体和被移出雌性的洞穴系统之间轮换弄脏的垫料，使被移出的雌性与它们的亲代群体保持日常的气味接触。此外，在这64天期间，来自各自亲代群体的非繁殖动物子集被定期移入被移出雌性的洞穴系统中，为期2天。因此，除了繁殖对之外，被移出的雌性与亲代群体动物的子集保持着持续的社交接触。所有四只被移出的雌性在与亲代群体分离后的3天内，尿液中孕酮水平升高（<2 ng/mg Cr），表明卵巢功能开始启动。被移出的雌性表现出正常的排卵周期，孕酮水平在25 - 35天内保持升高（孕酮的平均浓度±标准误；16.2±2 ng/mg Cr）。当被移出的雌性与亲代群体隔离时，它们发起攻击和性行为的频率显著增加。结果表明，来自整个群体的气味线索以及来自非繁殖群体成员的行为/触觉/声音线索并不是维持非繁殖雌性裸鼹鼠生殖抑制的主要线索。相反，我们的结果表明，裸鼹鼠中雌性的生殖抑制是由一种与优势地位相关的行为机制引起的，这种机制需要与繁殖雌性直接接触。
