Effects of Lactobacillus Lactis Supplementation on Growth Performance, Hematological Parameters, Meat Quality and Intestinal Flora in Growing-Finishing Pigs

SIMPLE SUMMARY: Recently, many probiotics have been used as feed additives in the livestock industry for various purposes. Specifically, Lactobacillus lactis (LL) is effective as a growth promoter, anti-stress agent and immune enhancer. However, studies evaluating the effects of LL on growing-finishing pigs are limited. Therefore, in this study, we evaluated the growth performance of growing-finishing pigs using different doses of LL as a supplementary additive. The findings suggested that the inclusion of LL in the diet had a positive effect on growth performance in the grower phase and on meat quality. ABSTRACT: Objective: The study was conducted to assess the effect of supplementation with Lactobacillus lactis (LL) on growth performance, hematological parameters, meat quality and intestinal flora in pigs from growing until slaughter. Methods: A total of 72 growing pigs (30.46 ± 3.08 kg) were randomly assigned to 3 groups (including 3 pens for each group, with 8 pigs in each pen). The three treatments comprised a basal diet (O-0) and two experimental diets supplemented for 14 weeks with 0.01% (O-100) and 0.03% (O-300) LL, respectively. Results: The final body weights of the pigs in the O-100 and O-300 groups were significantly higher (p < 0.05) than those of the O-0 group. In the grower phase, the average daily weight gain (ADG) and average daily feed intake (ADFI) of pigs fed the O-300 diet were higher (p < 0.05) than those of pigs fed the O-0 diet during the grower phase. BUN and MDA were significantly higher (p < 0.05 for all) in the O-0 group than in the O-100 and O-300 groups during the grower phase. No difference (p > 0.05) was observed in the hematological parameters among the three groups during the finisher phase. Counts of LL in the stomach were significantly higher (p < 0.05) in the O-300 group than in the O-0 group. Counts of Escherichia coli in the jejunum were significantly higher (p < 0.05) in the O-0 group than in the O-300 group. Furthermore, the hardness, cohesiveness, gumminess and resilience of longissimus dorsi muscle collected from pigs fed the O-300 diet were higher (p < 0.01; p = 0.024; p = 0.003; p = 0.014, respectively) than those of tissue collected from pigs fed the O-0 diet. Conclusion: Dietary LL supplementation increased final body weight, increased ADG in the grower phase and enhanced meat quality.