[01] Mariem Chaâbane, Department of Life Sciences, Sciences Faculty of Sfax, Sfax, Tunisia. [02] Imen Ghorbel, Department of Life Sciences, Sciences Faculty of Sfax, Sfax, Tunisia. [03] Awatef Elwej, Department of Life Sciences, Sciences Faculty of Sfax, Sfax, Tunisia. [04] Najiba Zeghal, Department of Life Sciences, Sciences Faculty of Sfax, Sfax, Tunisia. [05] Nejla Soudani, Department of Life Sciences, Sciences Faculty of Sfax, Sfax, Tunisia.

Weaning is a natural and inevitable phase of mammalian development. In both animals and humans, this process represents a transition from a milk based diet (low carbohydrate content) to a solid diet (relatively rich in carbohydrates). Both, the dietary change and the decline of the mother's attention during this critical period cause a state of stress in the offspring. The present review was designed to analyze the impacts of the weaning procedure on the digestive system and the behavior of mammals such as humans, rodents and pigs. Based on literature data, it appears that weaning is a complex process that requires physiological, microbiological and immunological adjustments in the digestive tract. The physiological changes are manifested by alterations of the intestinal anatomy, the activity of the digestive enzymes and the function of intestinal absorption. The composition of the intestinal flora undergoes changes depending of food and the environment. Weaning results also in the activation of the intestinal immune system following the introduction of new food and microbiological antigens. It involves also behavioral changes which depend largely on the age at which this process is performed. Thus, these data highlight the influence of diet on one of the early stages of mammalian development that may have an effect on the health during adulthood.

Weaning, Mammals, Diet, Digestive Tract, Behavior

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