Effects of Dietary Lactiplantibacillus pentosus and Salinomycin on Growth Performance, Meat Quality, Antioxidant Status, and Serum Parameters in Broilers Fed Diets Differing in Nutrient Density

Abstract

ABSTRACT The study aimed to evaluate dietary Lactiplantibacillus pentosus [LP]-based probiotic as an alternative to in-feed antibiotics for broilers fed diets containing different nutrient densities. A total of 630 day-old male Ross 308 broiler chicks were randomly assigned to 42 pens (15 birds/ pen) in a 2×3 factorial design with three additives (none, salinomycin at 60 mg/kg, or LP at 1.0 × 108 cfu/kg) and two nutrient density levels (optimal [OPT] or reduced [DEF]). The OPT diets increased (p<0.05) body weight gain in relation to the DEF ones. The LP diet impaired body weight gain and feed intake compared with the control and salinomycin diets (p<0.05). The LP diet lowered feed conversion ratio in the OPT diet, but increased it in the DEF diet, leading to a significant interaction between the two factors (p<0.05). Breast meat yields were increased in the salinomycin group but decreased in the LP group as compared to the control group (p<0.05). CIE a* and b* values in breast meat and CIE a* value in thigh meat were highest in broilers fed salinomycin as compared to the control groups (p<0.05). The OPT diets increased cooking loss in breast meat and decreased CIE L* value in thigh meat (p<0.05) in comparison to DEF diets. Serum superoxide dismutase was higher in the salinomycin and LP groups than in the control group (p<0.05). The salinomycin diet lowered jejunal secretory immunoglobulin A compared with the control group (p<0.05). An interaction between additives and nutrient density on serum glutamic oxaloacetic transaminase was observed (p<0.05). Under the conditions of this study, dietary L. pentosus S14 increased serum SOD activity but impaired growth performance and breast meat yield; therefore, this strain cannot be recommended as a direct replacement for salinomycin without further dose optimization, strain validation, and challenge-model testing.