Effects of butyrate glyceride-based feed ingredient supplementation on weanling pig performance, fecal dry matter, serum chemistry, and intestinal short chain fatty acid concentration.

Two experiments determined the effects of butyrate-based feed additives on weanling pig performance, fecal dry matter (DM), serum chemistry, and intestinal short chain fatty acids. In Exp. 1, 300 pigs, initially 5.5 kg, were used in a 38-d trial with 5 pigs per pen and 10 replications per dietary treatment fed in three phases. Six dietary treatments consisted of a control that did not contain any carbadox or pharmacological levels of Zn and Cu, and four diets that contained butyrate-based feed ingredients added at 0.1% to the control diet in all phases consisting of encapsulated butyrate, monobutyrin, a mono-tributyrin (MTB) blend, and tributyrin (Eastman; Kingsport, TN). In addition, there was a positive control that contained 3,000 mg/kg of Zn, 2,000 mg/kg of Zn, and 250 mg/kg of Cu in phases 1, 2, and 3, respectively, and 55 mg/kg of carbadox (Mecadox; Phibro Animal Health Corp.; Teaneck, NJ) in all phases. Overall (day 0 to 38), pigs fed the positive control had increased (P < 0.05) ADG, and day 10 fecal DM compared with all other treatments. Pigs fed MTB had increased (P < 0.05) G:F compared with monobutyrin with pigs fed other treatments intermediate. Pigs fed MTB had the greatest (P ≤ 0.046) day 10 hematocrit and hemoglobin without significant mean separation. Pigs fed MTB had increased cecal butyrate compared with the control with pigs fed other treatments intermediate. In Exp. 2, 2,238 pigs, initially 5.1 kg, were used in a 42-d trial with 26 or 27 pigs per pen and 14 replications per dietary treatment. Six dietary treatments consisted of a control, a primarily monobutyrin blend, a 2:3 ratio of MTB, a 3:2 ratio of MTB, a MTB with C8 and C10 monoglycerides (Eastman; Kingsport, TN), and a commercial feed additive consisting of micro-encapsulated acids, thymol, and botanicals. The control diet contained 3,000 and 2,000 mg/kg of Zn in phases 1 and 2, respectively, and 55 mg/kg of carbadox in both phases. Each feed additive was added to the control at 0.3% in phases 1 and 2, and 0.1% in phase 3. On day 10, pigs fed the MTB at a 2:3 ratio had increased (P < 0.05) fecal DM compared with the predominantly monobutyrin blend and commercial additive with pigs fed other treatments intermediate. Pigs fed both ratios of MTB had decreased (P < 0.05) granulocyte-macrophage colony stimulating factor and IFNγ compared with the primarily monobutyrin blend. In summary, MTB increased cecal butyrate, hematological components, and modulated inflammatory status of weanling pigs.