Growth, nutrient utilization and immunecompetence in broiler chicken fed probiotic, gut acidifier and antibacterial compounds

Abstract

A study was conducted to compare the efficacy of a gut acidifier (GA), a probiotic (PB) and an antibacterial (AB) feed additives in female commercial broiler diets. AB, PB and GA were supplemented separately to the maizesoyabean basal diet at the rate of 25, 10 and 300 g/100 kg, respectively and were fed ad libitum to broilers from 3 to 35 d of age. Each diet was offered to six replicate groups housed in raised wire floor stainless steel battery brooders. Body weight gain and excreta moisture contents were not influenced by the dietary treatments, whereas feed/gain, dry matter digestibility and nitrogen retention were improved and pH of ileal contents and excreta was reduced by PB feeding. Carcass variables were not affected due to treatment affect except liver fat content, which was significantly increased in GA fed broilers compared to AB. GA also reduced the pH of duodenal content. Feeding PB or GA improved antibody titers against New castle disease and infectious bursal disease virus. The total bacterial, coliform, and Escherichia coli counts in crop and caecal contents and intensity of air sac lesions to E. coli inoculation were low in broilers fed PB and GA. It is concluded that probiotic or gut acidifier can safely replace antibacterial compounds in broiler chicken diets with beneficial effects on immune response, intestinal bacterial colonization and resistance to E. coli challenge.