Morphology and enzymatic activity of the small intestinal mucosa of Iberian pigs as compared with a lean pig strain

Abstract

Castrated male Iberian (n=12) and Landrace x Large White (n=12) pigs were used to study histological structure and enzymatic activity in the small intestine at three points of the productive cycle (BW 15, 50 and 120 kg). Both stains were fed the same cereal-based diets (digestible energy = 11.7 kJ • g-1, and protein = 150 g • kg-1). Significant (P < 0.05) differences in histometrical parameters (villus hight, width and surface, crypt depth, villus hight / crypt depth relationship, mucosal thickness, muscular layer thickness, and number of goblet cells) of small intestinal samples were found among samples of small intestinal sections (duodenum, jejunum, ileum) at the three productive stages studied. Also, significant (P < 0.05) differences in histometrical parameters of small intestinal samples were found between Iberian and lean pigs at all productive stages, although these differences tended to disappear with age. Significant (P < 0.05) differences in enzymatic activities (lactase, sucrase, maltase, isomaltase, aminopeptidase, and alkaline phosphatase) of small intestinal samples were found between the different intestinal sections at all productive stages studied. Although significant (P < 0.05) differences in enzymatic activities of small intestinal samples were found between Iberian and lean pigs at all productive stages, values tended to equalize with pigs age. We concluded that differences previously found in dietary nutritional utilization between Iberian and lean strains are likely to be related to metabolic differences more than to lower intestinal absorptive or hydrolytic capacity.