Effect of Supplemental Sodium Butyrate on Gastrointestinal Tract Measurements in Sheep

The aim of the study was to determine the effect of sodium butyrate supplementation in the diet on reticulo-ruminal, omasal and abomasal digesta and tissue mass and small intestinal tissue mass and length. Eighteen rams (30.8 ± 2.1 kg; 12 to 15 months of age) were allocated to the study and fed 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, within block paired by body weight (BW), and 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 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. The statistical model included the fixed effect of treatment and the random effect of block and animal within pair. Dry matter intake was not different between treatments (862 and 864 g/d for CTRL and BUT, respectively; P = 0.82). Initial BW did not differ between treatments (30.8 and 31.1 kg for CTRL and BUT, respectively; P = 0.61) but final BW was greater for BUT compared to CTRL (33.4 vs. 32.2 kg; P = 0.03). Sodium butyrate supplementation increased butyrate concentration in the digesta of reticulo-rumen (20.7 vs. 11.7 mmol/L; P < 0.01), abomasum (2.0 vs. 1.3 mmol/L; P = 0.01) and proximal small intestine (0.68 vs. 0.22 mmol/L; P = 0.05). Reticulo-ruminal tissue mass tended to be greater for BUT compared to CTRL (21.4 vs. 20.4 g/kg of BW; P = 0.09). Omasal digesta mass was lower for BUT compared to CTRL (2.2 vs. 2.8 g/kg of BW; P = 0.02). Reticulo-ruminal digesta mass, abomasal tissue and digesta mass, omasal tissue mass and small intestinal tissue mass and length were not affected by BUT (P > 0.05). Supplemental sodium butyrate tended to increase reticulo-ruminal tissue mass and decreased omasal digesta mass but did not affect omasal and abomasal tissue mass, and small intestinal tissue mass and length in sheep (The study was supported by the National Science Centre (Poland) based on decision No. DEC-2013/11/B/NZ9/01938).