Abstract:
The effect of dietary direct-fed microbial (DFM) and antibiotics supplementation on health status and
growth performance of broiler chickens under hot humid environmental conditions was studied. A total
of 600 one-day-old Cobb hybrid broilers were randomly allotted to three dietary treatments. Three
hundred and twenty (320) birds were selected out of the 600 after phase 1 and allotted to four dietary
treatments: (i) Basal diet (BD) control, ii) BD plus DFM at the rate of 1.5 ml/kg, (iii) BD plus antibiotics at
the rate of 100 mg/kg and (iv) BD plus DFM and antibiotics at the same rate as earlier described. In
phase 1, birds fed DFM diet had lower feed intake (P<0.05) which did not affect weight gain but were
more efficient in converting feed to gain. In phase 2, increased feed intake, improved weight gain and
feed efficiency was observed for birds fed DFM diet. Growth performance of birds fed DFM diet was
similar to that of antibiotic diet. Mortality reduced in both phases in favour of DFM and was least
susceptible to disease occurrence. Increased intestinal acidity from a pH of 5.79 in control to 5.05 was
recorded for birds fed DFM diet. A reduction in serum cholesterol was recorded from 110.25 mg/dl in
control to 91.25 mg/dl in DFM fed group. It was more economical rearing broilers on DFM diet. It was
concluded that DFM can be a suitable alternative natural feed additive to conventional antibiotics as
growth and health promoter in a hot humid environment.
Key words: Direct-fed microbial, antibiotics, cholesterol, broiler.
