FACTORS INFLUENCING THE STRUCTURE AND FUNCTION OF THE SMALL-INTESTINEIN THE WEANED PIG - A REVIEW

At weaning, the young pig is subjected to myriad of stressors (e.g. ch ange in nutrition, separation from mother and littermates, new environ ment) which cause reduced growth. This post-weaning 'growth check' con tinues to represent a major source of production loss in many commerci al piggeries. Associated with weaning are marked changes to the histol ogy and biochemistry of the small intestine, such as villous atrophy a nd crypt hyperplasia, which cause decreased digestive and absorptive c apacity and contribute to post-weaning diarrhoea. In this review we ha ve outlined the major factors implicated in the aetiology of these cha nges, such as the role of enteropathogens, transient hypersensitivity to dietary antigens, and the withdrawal of milk-borne, growth-promotin g factors. Special attention has been paid to the role of food (energy ) intake as a mediator of intestinal structure and function after wean ing, although other influences such as the source of protein added to the diet may interact with food intake to alter,out structure and func tion. This is clearly an area of production concern, and future resear ch into areas such as manipulation of the immature digestive tract wit h exogenous growth factors and (or) dietary supplementation with 'non- essential' amino acids such as glutamine, appear warranted. (C) 1997 E lsevier Science B.V.