Influence of dietary supplementation of synbiotics as an alternative to antibiotic growth promoters on performance, ultrastructure and histomorphology of gut integrity in broilers

Abstract

A study was carried out to investigate the effect of dietary supplementation of synbiotics (combination of probiotics and prebiotics) as an alternative to replace antibiotic growth promoters (AGPs) – (Oxytetracycline OTC and Chlortetracycline CTC) and on the histomorphology and ultrastructure (SEM) of gut integrity of broilers. A total of 360 day old commercial male broiler chicks were randomly divided into 6 treatment groups with 12 replications of 5 birds each (6×12×5) and reared up to 42 d of age. The broilers were fed corn soya based broiler pre-starter (0-14 d), starter (15-28 d) and finisher (29-42 d) diets. The control diet (T1) was prepared with corn-soya diets without antibiotics, for remaining treatment groups (T2- T5) diets were formulated by corn-soya diets with different levels of antibiotics, OTC@ (100 mg/kg) (T2), OTC@ 200 mg/kg (T3), CTC @ 100 mg/kg (T4), CTC @ 200 mg/kg (T5) and synbiotic @250 mg/kg (T6) for 42 days. The results indicated that the body weight gain of broilers were increased significantly (P<0.05) in the dietary groups on supplementation of OTC, CTC or synbiotic. The morphology of intestinal samples by scanning electronic microscope (SEM) and histopathology revealed that there was a significant (P<0.05) difference in the height of intestinal (ileum) villi of broiler at 42 d fed with both OTC, CTC @100 mg and 200mg/kg diets and synbiotic @ 250mg/kg. The length of villus was highest in CTC 200mg/kg (844µm) followed by OTC 200mg/kg groups (759.8µm). Synbiotic (626.5µm) showed comparably increase in villi height than OTC, CTC 100 mg/kg and control group (543.3µm). There were no significant histopathological changes observed in the intestinal villi. It can be concluded that supplementation of synbiotics@250mg/kg can also be used as alternative to the AGPs in the broiler production replacing AGPs in the diet.