Peripheral anosmia attenuates female-enhanced aggression in male rats

doi:10.1016/0031-9384(91)90494-9

Physiology & Behavior

Volume 50, Issue 1, July 1991, Pages 33-40

https://doi.org/10.1016/0031-9384(91)90494-9 Get rights and content

Abstract

It is well established that male rats with prior access to sexually active females show enhanced offensive aggression toward unfamiliar male intruders. The present study assessed the importance of the sense of smell for this facilitatory effect. It was found in 2 independent experiments that anosmia, induced peripherally by surgically removing the olfactory epithelium and cutting the olfactory nerves, reduced baseline levels of offensive aggression and significantly attenuated the female-enhanced aggression effect. It was also found that sexual performance of anosmic rats was context-dependent, in that it was more impaired in the homecage environment than in standard observation cages. In contrast to sham-operated males, the experimental animals showed no preference for estrous over anestrous females in a mate choice test. Anosmic males did not appear more fearful than controls, as assessed in a hyponeophagia test, but they showed less exploratory behavior (rearing and head-dipping) in the hole-board test, and less rearing activity in automated activity boxes.

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Further support for the importance of olfactory stimuli comes from studies of anosmic subjects. Neither male nor female rats distinguish a sexual incentive from a social incentive after destruction of the nasal epithelium (Bergvall et al., 1991; Romero et al., 1990; Thor and Flannelly, 1978). It would seem, then, that olfactory stimuli are necessary for sexual approach whereas neither auditive nor visual stimuli are.
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Our results showed that the female of 1st entry was not sniffed more than the other females during the period with inaccessible females and during the period of choice, suggesting that one of the individual female odors was not more attractive than the others. Interestingly, several studies have shown the attractiveness of females' odors for male rats [12,13,16,34–37]. In these studies, the odors of females in estrus were approached more than those of sexually inactive females or males.
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ArticlePeripheral anosmia attenuates female-enhanced aggression in male rats

Abstract

Physiol. Behav.

Horm. Behav.

Physiol. Behav.

Pharmacol. Biochem. Behav.

Adv. Study Behav.

Brain Res. Rev.

Anim. Behav.

Physiol. Behav.

Neurosci. Biobehav. Rev.

Brain Res.

Physiol. Behav.

Trends Neurosci.

Physiol. Behav.

Behav. Neural Biol.

Physiol. Behav.

Olfactory cues and movement: stimuli mediating intraspecific aggression in the wild Norway rat

J. Comp. Physiol. Psychol.

Sexual behavior: stimulation by painful electrical shock to skin in male rats

Science

Influence of females on conflict among wild rats

J. Zool.

Effects of breeding in captivity on conflict among wild rats

J. Mammal.

Female-enhanced aggression in male rats: effects of genital anesthesia, castration or preoptic lesions

Behav. Neurosci.

Involvement of various senses in responses to individual housing in laboratory albino mice

Boll. Zool.

Olfactory bulbectomy and mucosal damage: effects on copulation, irritability, and interspecific aggression in male rats

J. Comp. Physiol. Psychol.

Responses of rats to sex odors

J. Comp. Physiol. Psychol.

Responses to feminine odors in normal and castrated male rats

J. Comp. Physiol. Psychol.

The olfactory threshold for estrous female urine in normal and castrated male rats

J. Comp. Physiol. Psychol.

Olfactory recognition of conspecifics by domestic Norway rats

J. Comp. Physiol. Psychol.

Article
Peripheral anosmia attenuates female-enhanced aggression in male rats