The behaviour of a nursing dam influences the development, physiology, and behaviour of her offspring. Maternal behaviours can be modulated both by environmental factors, including diet, and by physical or behavioural characteristics of the offspring. In most studies of the effects of the environment on maternal behaviour, F0dams nurse their own F1offspring. Because the F1are indirectly exposed to the environmental stressorin uteroin these studies, it is not possible to differentiate between effects on maternal behaviour from direct exposure of the dam and those mediated by changes in the F1as a consequence ofin uteroexposure. In this study, we used a mouse model of high-fat (HF) diet feeding, which has been shown to influence maternal behaviours, combined with cross-fostering to discriminate between these effects. We tested whether the diet of the F0dam or the exposure experienced by the F1pupsin uterois the most significant predictor of maternal behaviour. Neither factor significantly influenced pup retrieval behaviours. However, strikingly, F1in uteroexposure was a significant predictor of maternal behaviour in the 15 min immediately following pup retrieval while F0diet had no discernable effect. Our findings suggest thatin uteroexposure to HF diet programmes physiological changes in the offspring which influence the maternal behaviours of their dam after birth.
Effects of cross-fostering and developmental exposure to mixtures of environmental contaminants on hepatic gene expression in prepubertal 21 days old and adult male Sprague-Dawley rats
