Group mating among Norway rats I. Sex differences in the pattern and neuroendocrine consequences of copulation

doi:10.1016/S0003-3472(82)80051-1

Animal Behaviour

Volume 30, Issue 2, May 1982, Pages 398-409

https://doi.org/10.1016/S0003-3472(82)80051-1 Get rights and content

Abstract

The copulatory pattern of groups of rats (Rattus norvegicus) was studied in the laboratory in a seminatural environment. In a given mating session, every oestrous female copulated with each male; likewise, every male copulated with each oestrous female. While individual males and females experienced similar amounts of copulation, there were dramatic sex differences in sequence and temporal pattern. Males mated in a multiple intromission pattern and had more ejaculatory series when several females were in oestrus. In contrast, females received intromissions and ejaculations in a random order, not in the sequence of a male ejaculatory series. Males copulated at shorter intervals than females did, a temporal sex difference that was determined by the pattern of female solicitations and male approaches. These sex differences are used to discuss the different units of analysis that are appropriate for male and female sexual behaviour in this species. Furthermore, the sex differences in the temporal pattern of copulation which emerged during group mating parallel the known sex differences in the temporal parameters of the neuroendocrine reflexes which mediate successful reproduction in the domestic strain.

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Group mating among Norway rats I. Sex differences in the pattern and neuroendocrine consequences of copulation

Abstract

Horm. & Behav.

Behav. Neural. Biol.

Anim. Behav.

Physiol. Behav.

Physiol. Behav.

Horm. & Behav.

Anim. Behav.

Anim. Behav.

Adv. Study Behav.

Anim. Behav.

Effects of the male's copulatory behaviour on successful pregnancy of the female rat

J. comp. physiol. Psychol.

Observational study of behaviour: sampling methods

Behaviour

A test for measuring sexual excitability in the female rat

Comp. Psychol. Monographs

An analysis of social behaviour in wild rats

Proc. Zool. Soc. Lond.

Characteristics of masculine sex drive

Anatomical evidence for epididymis as prime mover in the evolution of the scrotum

Am. J. Anat.

Effects of single and multiple enforced intercopulatory intervals on the sexual behaviour of male rats

J. comp. physiol. Psychol.

Blocked sexual receptivity in grouped female golden hamsters, the result of contact induced inhibition

Biol. Reprod.

The Ecology and Sociobiology of the Norway Rat

USPHS Publication No. 1008

Cyclical patterns of copulation in the male rat

Influence of male copulatory behaviour on sperm transport, pregnancy and pseudopregnancy in female rats

Physiol. Behav.

A comparison of reproductive potential of two rat populations

Ecology

Maternal age and male behaviour in relation to successful reproduction by female rats (Rattus norvegicus)

J. comp. physiol. Psychol.

Changes in the inter-intromission interval during uninterrupted copulation in rats

Psychon. Sci.

Copulatory behaviour of Syrian golden hamsters in a one-male two-female test situation

Anim. Learn. & Behav.

Intromission pattern and species vaginal code in relation to induction of psueudopregnancy

Science, N.Y.