TDK conference 2011

The short chain fatty acid butyrate is widely used as a feed additive because of its positive effect on growth performance and on the gut microflora, first of all in poultry and pig nutrition. This is of special importance because of the banning of the traditional antimicrobial growth promoters in the EU.

The aim of our study was to compare the effects of alimentary supplied butyrate on growth performance and on micromorphology of small intestinal mucosa in broiler chicken and rat, the latter as a model animal for monogastric mammals.

Twenty one-day-old Bábolna Tetra broiler chickens were included in the chicken feeding experiment. Experimental animals were randomized into two groups: ten control chickens were fed by a control starter diet, and ten broilers by the same feedstuff supplemented with sodium butyrate with the concentration of 1.5 g/kg diet. Twenty five-weeks-old Wistar rats were included in the rat feeding experiment. They were classified into two groups: ten control animals were fed by commercially available pelleted diet for rodents, while ten rats with the same feed, supplemented with sodium butyrate with the concentration of 1.5 g/kg diet. Growth parameters and feed intake were measured regularly. Animals were extermined after 21 days and histological samples were taken from the jejunum in both species. Gut samples were examined after hematoxylin-eosin staining with histometrical measurement of height of villi, depth of crypts and height of enterocytes.

It was found that dietary supplementation of sodium butyrate had beneficial effects on body weight gain, feed intake and feed conversion ratio in broiler chickens in the first week of life. However, butyrate supplementation had no positive effects on growth of rats directly after weaning. The absence of the positive effect can be explained with the already matured gut flora at the time of the beginning of the experiment. Butyrate tended to increase height of villi and depth of crypts in both species, while butyrate had a significant positive hypertrophic effect on the enterocytes in chicken, but not in rat. On the basis of these results, we suggest that influence of butyrate on the growth parameters might be based partially on the morphological changes of the small intestinal mucosa.