Use of Growth Promoter in Feed: Tylosin Phosphate and Oxytetracycline Di-Hydrate Show Synergistic Effect on the Haematological Parameters and Biochemical Components of Broiler Chicken Blood

The antibiotic growth promoters (AGPs) are provided in poultry feeds as an additive on sub-therapeutic level. The in vivo study was designed to evaluate the effect of oxytetracycline di-hydrate (OXY) and tylosin phosphate (TP) on different blood physiological and biochemical parameters in broiler chicken. AGPs supplement alone and in combinations were provided as pre-starter (days 1-12), starter (days 13 to 24) and finisher (day 25 to 42) feed. Standard broiler rearing temperature was provided in the shed. Results showed that the OXY and TP had significant (P<0.05) effect on physiology of blood parameters, mainly on hemoglobin (Hb) and erythrocytes (RBCs) in all treatment groups treated till day 42 compared with the control group. Remarkably, the AGPs showed a positive impact on the liver enzymes such as alanine aminotransferase (ALT) and aspartate aminoransferase (AST) on day 42. A non-significant effect was seen on hematological and biochemical profile of liver and kidney of broiler chicken on days 14(th) and 28(th). In conclusion, the study showed significant synergistic effect of TP and OXY on the Hb, RBC and liver enzymes such as ALT and AST that ultimately lead to promote the growth and can be used safely at sub-therapeutic levels in food and/or water of broiler chicken. The result further determined that the longer use (6 weeks) of AGPs had no harmful effect on blood, liver and kidney in broiler chicken and can be used after withdrawal period.