Background and Aim: The use of antibiotic growth promoters (AGPs) in the poultry industry has raised concern because of their potential harm to human health. Emerging evidence suggests that probiotics are a safer substitute, although little research has explored this in Bangladesh. We recently isolated local bacterial strains with probiotic properties. We aimed to determine their impact on the growth, hematobiochemical parameters, and production costs of broiler chicks relative to that of a commercial probiotic (CP) and AGP.

Materials and Methods: Day-old male broiler chicks (Cobb 500, n=63) were divided equally into three experimental groups (three replicates per group and seven chicks per replicate). First group was fed a basal diet supplemented with the AGP, ciprofloxacin (CTL group), second group was fed a basal diet supplemented with the CP, Protexin^® (CP group), and the third group was fed a basal diet supplemented with our isolated bacterial strains (study probiotic [SP] group) for 36 days. Body weight was recorded daily, and relative growth rate (RGR), feed conversion ratio (FCR), and organ weights and carcass yields were calculated at the study's end. Blood obtained on day 36 was used to determine the number of red blood cell (RBC) and white blood cells (WBCs), hemoglobin (Hb) concentration, packed cell volume, erythrocyte sedimentation rate, as well as levels of serum glucose, total and high-density lipoprotein (HDL) cholesterol, and triglycerides (TGs). Total production costs were estimated by summing the variable and fixed costs.

Results: Chicks in both the CP and SP groups experienced significant decreases in blood glucose levels and significant increases in BW, RGR, FCR, levels of RBC and WBC, Hb concentration, and packed cell volume compared with those in the CTL group (p<0.05 for all). Our data suggested a numerical reduction (p>0.05) in levels of total cholesterol, TGs, and HDL in the SP and CP groups when compared to the CTL group. In addition, both CP and SP treatments resulted in significant (p<0.05) gains in net profit compared with the treatment given to the CTL group.

Conclusion: Administration of probiotics, either from a commercialized or local source, led to greater improvements in growth, hematological parameters, and net profits of broiler chicks when compared with that of an AGP. This suggests that they are suitable alternatives to the AGPs used in poultry feed and that our isolated strains, in particular, are an ideal option for farmers in Bangladesh.

Keywords: Cobb 500 broiler, Enterococcus faecium, Pediococcus acidilactici, probiotics, serum biochemistry.