The aim of the study was to determine the effect of yeast probiotic on body weight, and the activities of anti-oxidant enzymes: superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx), and malondialdehyde (MDA) concentration of broiler chickens. The experiment was carried out on hybrid Hubbard broiler chickens (n = 200). Two-hundred day-old chicks were randomly selected and distributed into four groups of 50 day-old chicks each: Control, C, and treatment groups comprising T1, T2 and T3 administered with 0.25 mL, 0.5 mL and 1.0 mL yeast probiotic, respectively. Chicks were fed a commercial starter diet for the first 28 days of age, followed by pelleted finisher diet from 29 to 42 days. Chickens in T1 had a significantly (p < 0.01) higher body weight at 4th week of age when compared with the control. SOD activity in all treatment groups was not significantly (p > 0.05) different when compared with the control. GPx activity was significantly (p < 0.01) higher in T1, when compared with the control. GPx activity in T2 was higher (p < 0.01) when compared with the control. There was no significant (p > 0.05) difference in MDA level in all the treatment groups. In conclusion, administering yeast probiotic supplement increased body weight and enhanced serum anti-oxidant enzyme activities of broiler chickens.

The aim of the study was to investigate the effect of supplemental probiotic preparation on performance indices, serum enzymes and electrolytes of broiler chickens. Two hundred (200) day-old Marshall broiler chicks were randomly selected and distributed based on the level of supplementation into four groups of 50 chicks each (Control, C; E 1 0.5%, E 2 1.5% and E 3 2.0%). Chickens fed 2.0% probiotic had a significantly higher body weight when compared with the control group. Activity of alanine aminotransferase differed significantly in the group E 1 0.5%, and especially (p<0.01) in the group E 1 1.5%. Alkaline phosphatase activity decreased significantly (p<0.05), when compared with that of the control group. Serum calcium and phosphorus concentrations in experimental groups were significantly higher. Potassium concentration in experimental group rose significantly (p<0.05), when compared with that of the control broiler chickens. In conclusion, supplementing broiler feeds with 2.0% yeast probiotic improved performance indices, serum enzyme activities and enhanced the maintenance of electrolyte homeostasis in broiler chickens.