Effect of dietary fiber source on the growth performance and intestinal microflora in piglets

Growth performance and the levels and enzymatic activity of intestinal lactobacilli were studied in weaned piglets fed for 4 weeks with basal diets containing different sources of dietary fiber. These included: 1. 50% corn and 50% rice bran (T1) 2. 100% rice bran (T2) 3. 50% corn and 50% sawdust (T3) 4. 100% sawdust (T4), and 5. 100% corn used as control (T5). Most groups showed similar body weight (BW) gain as the control (T5) group, whereas T4 animals showed significantly lower (P < 0.05) BW gain than T5, which was related to the lowest feed intake in T4. While the blood chemistry profiles were similar in most groups, T4 animals had a higher (statistically non significant) serum levels of blood urea nitrogen, aspartate aminotransferase and alanine aminotransferase. T2 and T3 groups had the highest (P < 0.05) number of anaerobic bacteria in the feces and intestines compared to T5, while no differences were observed between T4 and T5. Initial screening for pH and bile acid resistance resulted in 23 strains of intestinal lactic acid bacteria, mostly from T3 and T4 groups, of which 61% produced one or more dietary enzymes, including protease, cellulase, phytase, and α- amylase. Although high level of sawdust in piglet diets negatively affects growth and health performance, if mixed with other sources of fiber, it may offer beneficial and cheaper alternative source of dietary fiber that ensures acceptable growth performance and promotes intestinal microflora with beneficial digestive enzymes.