Protein levels and highly fermentable carbohydrate as intestinal microbiota modulators of weanling pigs

Abstract

The objective in this study is to evaluate the possible synergistic effect between dietary crude protein (CP) level reduction with crystalline amino acid supplementation and citrus pulp inclusion in the diets of weanling pigs on growth performance, incidence of diarrhea, intestinal histology, short-chain fatty acids (SCFA), branched-chain fatty acids (BCFA), lactic acid, and ammonia concentrations, bacterial enumeration, and proinflammatory cytokines gene expression. One hundred eight piglets weaned at the age of 21 days will be used in a randomized complete block design in a 2 x 2 factorial arrangement of treatments with two CP levels (the animal requirement and four percentage units reduction in the animal requirement) and two citrus pulp levels (0 and 7.5%), with nine replicates per treatment and three animals per experimental unit. Experimental period will consist of 28 days during which animals will be fed a pre-starter I diet (days 1 to 14) and pre-starter II diet (days 15 to 28). The incidence of diarrhea will be evaluated during the first 14 days of the study. On days 7 and 28, duodenal, jejunal, and ileal samples will be collected for histological analyses, and ileal, cecal, and colon digesta will be sampled for bacterial enumeration and SCFA, BCFA, lactic acid, and ammonia determinations. Intestinal mucosa samples will be collected on day 7 for proinflammatory cytokines gene expression analyses. Statistical analysis will be performed using the GLM procedure of SAS (P < 0.05). (AU)