Testosterone replacement induced paternal behaviour in the Mexican volcano mouse Neotomodon alstoni (Rodentia Muridae)

摘要

Although the first studies that correlated paternal behaviour and testosterone levels in plasma reported that this hormone may have an inhibitory effect in paternal behaviour of the mammals, subsequent studies indicated that this steroid hormone is necessary for the displaying of paternal behaviour. We examined the effect of castration and testosterone replacement in the Mexican volcano mouse, a rodent that in captivity showed high levels of paternal care. In this rodent, testosterone replacement induced paternal behaviour in a considerable percentage of mice, despite the fact that in the first exposure to pups most of them were aggressive. These results suggest that testosterone is involved in the neuroendocrine mechanisms that suppress infanticide behaviour and express parental behaviour in this rodent. However, in agreement with our results, it seems that rather than the concentration of this hormone, an increase in testosterone level functions like a stimulus that triggers the onset of paternal behaviour.