Evaluating the efficacy of Lactobacillus acidophilus derived postbiotics on growth metrics, Health, and Gut Integrity in broiler chickens.

Continuous use of antibiotics in poultry feed as growth promoters poses a grave threat to humanity through the emergence of antibiotic resistance, necessitating the exploration of novel and sustainable alternatives. The present study was carried out to evaluate the performance of postbiotics derived from Lactobacillus acidophilus in broiler birds. The postbiotics were harvested by culturing probiotic bacteria from the stock cultures at the required temperature and duration under laboratory conditions and supplemented to broilers via feed. For experimentation, 480-day-old CARI-Bro Dhanraja (slow-growing broiler) straight-run chicks were randomly split up into six groups. Treatment groups diets are as follows: T1- Basal diet (BD)+0.2%(v/w) MRS Broth/ uninoculated media; T2 - BD + Antibiotic (CTC); T3- BD + Probiotic; T4, T5 & T6 - BD + postbiotics supplementation of 0.2%, 0.4% and 0.6% (v/w) respectively. The chicks were raised under an intensive, deep litter system with standard protocol for 6 weeks. Results showed that 0.2% of postbiotics (T4) had significantly (P < 0.001) higher body weight (1677.52 g) with better FCR (1.75) and immune response. Postbiotic supplementation altered various serum attributes positively, in this study. Significant (P < 0.001) reductions in total plate counts (TPC), coliform counts, and maximum Lactobacillus counts were recorded in all postbiotic-supplemented groups. The villus height (1379.25 μm), width (216.06 μm) and crept depth (179.25 μm) showed significant (P < 0.001) improvement among the treatment groups on the 21st and 42nd day of the experimental trial, with the highest value in the T4 group (0.2% postbiotic supplementation). Jejunal antioxidant values also noted significantly (P < 0.001) higher values in T4 group. The study concludes that 0.2% postbiotic supplementation can act as a substitute to antibiotic growth promoters and also combat the disfavour activity of probiotics in broilers.