Abstract
A total of 710 pigs (Line 400 × 200, DNA, Columbus, net energy (NE)) were used in two experiments (Exp. 1: initially, 6.3 ± 0.05 kg; Exp. 2: initially, 6.8 ± 0.05 kg) to evaluate the effects of two medium-chain fatty acid (MCFA) based products on nursery pig growth performance. Following their arrival at the nursery facility, pigs were randomized to pens (five pigs per pen) and allowed a 4-d acclimation period. Thereafter, pens of pigs were blocked by initial weight and randomized to dietary treatment. In Exp. 1, the dietary treatments were a dose titration of: 0%, 0.5%, 1.0%, or 2.0% MCFA-based additive, as well as a diet including 1.0% MCFA from a 1:1:1 blend of C6:0, C8:0, and C10:0. In Exp.2, dietary treatments consisted of a basal diet containing no MCFA (control), the control diet with a 1.0% inclusion of four different blends of MCFA, lactic acid, and monolaurin or a diet with 1.0% added MCFA (a 1:1:1 blend of C6:0, C8:0, and C10:0). The four blends consisted of 50% C6:0, 20% lactic acid, and increasing levels of monolaurin (0%, 10%, 20%, and 30%) at the expense of C12:0 (30%, 20%, 10%, and 0%). Treatment diets were formulated and manufactured in two dietary phases. Data were analyzed as a randomized complete block design with pen as the experimental unit. In Exp. 1, overall (days 0-34), increasing CaptiSURE increased (linear, P ≤ 0.014) average daily gain (ADG) and average daily feed intake (ADFI). Feed efficiency improved (quadratic, P = 0.002) with increasing CaptiSURE up to 1.0% of the diet with no benefit thereafter. There was no evidence for differences between pigs fed 1.0% CaptiSURE and pigs fed the 1.0% MCFA blend of C6:0, C8:0, and C10:0. In Exp. 2, overall (days 0-35), pigs fed the 1.0% 1:1:1 MCFA blend had increased (P < 0.034) ADFI and ADG resulting in 0.9 kg greater final weight (P = 0.014) compared with the control group. There was no evidence that the mean performance of pigs fed the four blends of MCFA, lactic acid, and monolaurin were different from the pigs fed the control diet. In summary, the addition of a 1.0% 1:1:1 blend of C6:0, C8:0, and C10:0 in nursery pig diets improved ADG, ADFI, and gain to feed ratio (G:F) compared with pigs fed the control diet. In addition, providing nursery pigs with the MCFA product CaptiSURE, up to 2% of the diet, resulted in linear improvements in ADG and ADFI. Altering the C12:0 to monolaurin ratio and adding lactic acid did not improve growth performance compared with pigs fed the control diet.