Protected organic acid blends as an alternative to antibiotics in finishing pigs

Abstract Text: Organic acids are of interest in pig feeding as promoters of gut health and growth, as pressure mounts to reduce or eliminate the use of antibiotics as growth promoters. A total of 120 finishing pigs [(Yorkshire×Landrace)×Duroc] with an average BW of 49.7 kg were used in 12-wk growth assay to determine the effects of protected organic acids blends (fumaric, malic and citric acid) on growth performance, nutrient digestibility, fecal micro flora, meat quality and fecal gas emission. Pigs were allotted to pen based on BW and sex with 4 pigs/pen and 10 pens/treatment. Treatments were corn soybean meal-based diet as control and the control with 0.1% and 0.2% protected organic acid blends. Dietary treatment with protected organic acid blends linearly increased (P < 0.001) ADG during 0 to 6 week, 6 to 12 week as well as overall with the increase in the inclusion level of organic acids in the diet. However, ADFI and G:F were not influenced by organic acids supplementation. The DM (75.3%, 77.5% vs 72.63%), N (76.05%, 79.05% vs 72.68%), and energy digestibility (78.97%, 79.43% vs 74.3%) increased linearly (P < 0.001) with the increase in the dose of protected organic acid blends during 12 week. During week 6 and 12, fecal ammonia emission linearly decreased (P = 0.01 and P< 0.001, respectively) on d 3 and d 5 of fermentation and acetic acid emission decreased linearly (P < 0.001) on d 5 and d 7 of fermentation on 12 week. Supplementation of organic acid blends linearly increased the longissimus muscle area (49.16cm², 50.79cm² vs 47cm²) with increasing level of organic acids. Based on sensory evaluation, score on color of meat showed linear and quadratic effects (P < 0.001, P < 0.002 respectively) and score on firmness of meat showed quadratic effects (P = 0.003) with the increase in the level of organic acid blends in the diet. During the 6 week, increment in the level of protected organic acid blends linearly decreased (P = 0.01) E. coli counts and linearly increased (P = 0.004) Lactobacillus counts in the feces. During 12 week, a linear reduction (P < 0.001) of E. coli counts and the tendency of linear increase (P = 0.06) in Lactobacillus count in the feces were observed with the increase in the level of organic acid blends. In conclusion, 0.2% protected organic acids blends positively affected growth performance, nutrient digestibility, fecal gas emission and meat quality in finishing pigs.

Keywords: growth performance, micro flora, protected organic acids