The effect of a new probiotic preparation on the performance and faecal microflora of broiler chickens

The aim of the study was to examine the possibility of replacing antibiotic growth promoters with a new probiotic preparation. One gram of the preparation contains: 4.7 x 10(7) of LAB (Lactobacillus casei/paracasei LOCK 0920, L. brevis LOCK 0944, L. plantarum LOCK 0945), 2.0 x 10(3) of yeast (Saccharomyces cerevisiae LOCK 0140) and a 50 mg of extract from Yucca Schidigera. The experiment was conducted on 99 female broilers divided into three groups consisting of 33 chickens, kept separately. A wheat- and soybean meal-based diet was divided into three parts: A (containing 1 g/kg of probiotic for starter and grower diets and 0.5g/kg for finisher diet), B (containing 14 mg/kg of flavomycin), and C (unsupplemented). The diets were fed from Day 1 to Day 41 of life. Final BW was on average 2.4 kg in all groups, FCR was 1.63 kg feed/kg BWG, neither BWG nor FCR nor mass of the liver, pancreas and gastrointestinal tract were significantly influenced by supplementing the diet with either additive. Special attention should be drawn to the fact that supplementing feeds with a probiotic preparation already after one week of breeding considerably decreased the number of Clostridium bacteria in broilers' faeces. Nevertheless, it should be emphasized that in this study the excreta of chickens fed with the feed mixed with a probiotic contained the lowest changeability of the number bacteria of the Enterobacteriaceae family and bacteria belonging to coli groups in individual weeks of breeding. It may be concluded that the studied probiotic can be considered as a substitute for antibiotic growth promoters in broiler diets.