Incidence of rotavirus in artificially reared pigs and some effects of diarrhoea on the physiology and histology of the gastrointestinal tract.

Pigs reared on a milk substitute from two days old often developed diarrhoea, but suckled littermates remained healthy. Only in a few pigs was diarrhoea associated with the presence of rotavirus. Rotavirus was also present in some healthy pigs, and was associated with a reduction in villus length. Pigs with diarrhoea usually had an increased amount of digesta in the stomach and a reduction in lactase activity in the small intestine but villus length was unchanged. There was no evidence of lactose malabsorption.