Effect of Supplemental Sodium Butyrate on the Activity of Carbohydrate-Digesting Enzymes in the Reticulo-Ruminal Digesta and Brush Border Enzymes in Sheep

The aim of the study was to determine the effects of sodium butyrate supplementation in the diet on activities of carbohydrate-digesting enzymes in the reticulo-ruminal digesta and brush border enzymes in sheep. Eighteen rams (30.8 ± 2.1 kg; 12 to 15 months of age) were allocated to the study and fed a diet without (CTRL) or with sodium butyrate (BUT; 3.6 g/kg of offered dry matter). The rams were allocated to the study in four blocks of 6, 4, 4 and 4 rams, respectivrely, within block paired by body weight (BW), and ram within pair randomly allocated to treatments (9 rams/treatment). Diet consisted of 65% of chopped meadow hay, 19.5% of concentrates and 15.5% of ensiled ground high moisture corn grain (on dry matter basis). Dry matter intake was limited to 2.75% of initial BW. Feed was offered in two equal meals at 0700 and 1500. Sodium butyrate was mixed with the concentrates and high moisture corn grain prior to feed allocation. Experimental diets were fed for 2 weeks and rams were killed 3 h after morning feeding. Reticulo-ruminal digesta was collected and analyzed for amylase, cellulase, xylanase, inulinase and pectinase activities, whereas in the epithelia of the duodenum, proximal, middle and distal jejunum and ileum activity of maltase, aminopeptidase A, aminopeptidase N and dipeptidylpeptidase IV were determined. The statistical model included the fixed effect of treatment and the random effects of block and animal within pair. Amylase activity in the reticulo-ruminal digesta was greater for BUT compared to CTRL (17.7 vs. 14.9 U/g of digesta dry matter; P = 0.04) whereas cellulase and xylanase activities were lower for BUT compared to CTRL (8.4 vs. 10.5 and 17.3 vs. 26.1 U/g of digesta dry matter for cellulase and xylanase activity, respectively; P ≤ 0.02). Aminopeptidase A and dipeptidylpeptidase IV activities in the distal jejunum were lower for BUT compared to CTRL (30.8 vs. 44.6 and 14.5 vs. 20.5 U/mg of protein for aminopeptidase A and dipeptidylpeptidase IV activity, respectively). Under the conditions of this study, dietary sodium butyrate increased amylase activity, but decreased cellulase and xylanase activity in the reticulo-ruminal digesta and decreased aminopeptidase A and dipeptidylpeptidase IV activities in the distal jejunum of sheep (The study was co-supported by the National Science Centre (Poland) based on decision No. DEC-2013/11/B/NZ9/01938 and Statutory Research Found of The Kielanowski Institute of Animal Physiology and Nutrition Polish Academy of Sciences).