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Evaluation of dietary acidifiers on growth performance of nursery pigs
Three 28-d experiments evaluated dietary acidifiers on the growth performance of nursery pigs housed under both university and field conditions. All diets were corn-soybean meal-based and fed in meal form. Each experiment consisted of a 2-phase diet series. The same 4 dietary treatments were evaluated in all 3 experiments, including a control with (1) no acidifier; (2) 0.5% Vevovitall (DSM Nutritional Products, Parsippany, NJ); (3) 0.2% Kem-Gest (Kemin Americas, Des Moines, IA), or (4) 0.05% ButiPearl (Kemin Americas). In Exp. 1, 280 weanling pigs (PIC 327 × 1050, initially 7.3 kg, 3 d postweaning) were used with 7 pigs per pen and 10 pens per treatment. From d 0 to 14, pigs fed Kem-Gest tended to have increased (P<0.07) ADG (245, 236, 263, 240 g, respectively) compared with pigs fed other treatments. From d 14 to 28 and overall (d 0 to 28), no differences were observed in ADG, ADFI, or G:F among treatments. In Exp. 2, 1,728 nursery pigs (PIC 327 × 1050, initially 5.8 kg, 10 d postweaning) were used with 48 pigs per feeder (24 pigs per pen) and 9 feeders (replications) per treatment. Treatment diets were fed from d 0 to 14, and a common diet was fed from d 14 to 28. From d 0 to 14, pigs fed the control diet had decreased (P<0.001) ADG (299, 367, 354, 363 g, respectively) and G:F (0.733, 0.810, 0.813, 0.825, respectively) compared with pigs fed diets with acidifiers. From d 14 to 28, there were no differences in performance between treatments. Overall (d 0 to 28), there were no differences in ADG, ADFI, or G:F but pigs fed diets containing acidifiers were approximately 0.95 kg heavier at the conclusion of the trial. In Exp. 3, 1,800 nursery pigs (PIC 327 × 1050, initially 7.4 kg, 13 d postweaning) were used with 50 pigs per feeder (25 pigs per pen) and 9 replications per treatment. Treatment diets were fed throughout the entire trial (d 0 to 28), with no differences in ADG, ADFI, or G:F observed. In conclusion, the responses to dietary acidification were inconsistent across experiments with pigs fed acidifiers having improved growth performance in Exp. 2, but not Exp. 1 and 3. More research is needed to fully elucidate the acidifier response for weanling pigs.
Keywords: acidifiers, benzoic acid, pig