Effects of double neonatal stress on female rat sexual behaviour

Abstract

Neonatal stress affects psychological and physiological development and may be associated with affective disorders. The aim was to examine the effects of double neonatal stress (DNS) - a combination of limited bedding and nesting (LBN) and repeated maternal separation (MS) - on the oestrous cycle and sexual behaviour of adult female rats. LBN was achieved by removing part of the wood shavings from the boxes. In the control group, each box was lined with 100 g of wood shavings, while in the experimental group there were only 10 g of wood shavings. MS was performed from P1 (P0 = day of birth) to P15. At P90, the sexual response of females in oestrus was evaluated. Statistical analysis was performed using two-way analysis of variance followed by Tukey's test. The size and profile of the oestrous cycle and the sexual behaviour of female rats submitted to the DNS were considered, as well as the influence of female behaviour on the sexual response of male rats. Female rats submitted to DNS showed a reduction in the lordosis quotient, suggesting a reduction in female receptivity. These rats also showed a reduction in the number of hops and darts, the number of ear wiggles, and the genital exploration time rate, suggesting a reduction in proceptivity. The males that interacted with the females of the DNS group showed a reduction in intromission ratio. Experimental model that mimics neonatal factors that affect adult female sexual response will allow more effective interventions to prevent and treat such changes. In addition, analysis of the female sexual response makes it possible to assess the general state of health and quality of life. In female rats, DNS exerted inhibitory effects on sexual behaviour. LBN was probably the most important factor. In conclusion, combating childhood poverty can be a key measure to prevent problems in the sex life of adults and improve overall health.

Keywords: Double neonatal stress; Female Rat Sexual Behaviour; Limited bedding and nesting; Maternal separation; Sex.