Abstract

This study was conducted to evaluate the effects of probiotics and organic acids, as alternative feed additives to antibiotics, on productive performance of broilers. Two different types of probiotics varying in the microbial content were tested and organic acids blend was compared against a single organic acid (lactic acid). One hundred and ninety eight broiler chicks were randomly allocated into six treatments, each with 33 chicks. Every treatment consisted of 3 replicates with 11 birds per replicate. The dietary treatments were a control diet without any feed additives or the same control diet supplemented either with a commercial antibiotic (Maxus®G200), probiotics (Bactocell® or Biopellet-S®) or acidifiers (Salmo-Nil Dry® or lactic acid). The antibiotic was added to the diet at the rate of 0.005%, whereas the probiotics were used at 0.01%. The product Salmo-Nil Dry® was provided to the diet at a level of 0.4%, whereas the lactic acid was used at 0.20 %. It was found that the antibiotic, probiotics and lactic acid increased the body weight. All dietary supplements improved the FCR compared to the control. The additives reduced the serum cholesterol level and the pH of small intestine but did not affect the carcass yield, breast or organ weights. The feed supplements showed a numerical decrease in intestinal aerobes, fecal coliforms and E. coli counts. In addition, all additives significantly reduced total aerobic and staphylococcus counts in the carcass meat, with a numerical decrease in E. coli count. In conclusions, probiotics and acidifiers can be used as potential alternatives to antibiotics in broiler diets. No difference between the used types of probiotics was detected. Lactic acid alone seems to produce better performance results than the organic acid mixture. The effect of lactic acid produced by bacteria might be similar to that of the chemical one.