Investigation of the functions of coprophagy in juvenile rats

Five experiments examined possible functions of the ingestion of maternal anal excreta by juvenile rats. Ss were 24 recently parturient Long-Evans rats and their 440 pups. No strong support was found for hypotheses suggesting that (a) maternal excreta serves as a major transition diet from mother's milk to solid food, (b) ingestion of maternal excreta influences pup diet selection at weaning, or (c) ingestion of maternal excreta is a necessary condition for inoculation of pups with enteric bacteria. Some support was found for the hypothesis that maternal excreta can serve as a short-term emergency food supply for rat pups after weaning. It is proposed that pup ingestion of maternal anal excreta may not be a functionally meaningful unit of behavior in preweaning rats. Allocoprophagy may be one facet of a broader pattern of oral exploration in which functional significance resides. (23 ref)