Effect of Pediococcus spp. in feed instead of antibiotic on broiler chicken body weight, mortality, slaughter traits and meat quality.

Abstract

in an experiment performed on 608 ross 308 broiler chickens the effect of dietary Pediococcus Spp. 840 and Spp. 841 lactic acid bacteria (lab) in the presence of mannan oligosaccharide and fumaric acid compared to the control unsupplemented group and the group supplemented with Lactobacillus acidophilus 842 (lac) was studied. the body weight, feed intake, feed conversion, mortality, dressing percentage, proportion of valuable cuts in the carcass and physicochemical characteristics of breast muscle were investigated. probiotic bacteria significantly reduced broiler mortality compared to the control group (p<0.01). no significant differences between feed intake and feed conversion were found. feeding Pediococcus Spp. significantly increased chickens' slaughter weight and carcass weight (p<0.01). there were no significant differences in the weight and proportion of breast and leg muscles, and in the weight of gizzard, liver and depot fat. no significant differences occurred for the dry matter, protein and fat content of breast muscles. the same held true for blood plasma components and physical characteristics of muscle tissue such as hardness, springiness, cohesiveness, gumminess, chewiness and resilience. it was concluded that probiotic bacteria do not significantly modify the physicochemical and sensory parameters of breast muscles from broiler chickens. key words: lactic acid bacteria, broiler chickens, body weight, feed conversion, meat composition, physical characteristics of meat Oligosaccharides, low-molecule organic acids and probiotic lactic acid bacteria have shown positive effects on reducing chicken mortality due to digestive tract infections, thus decreasing rearing costs (Patterson and Burkholder, 2003; F. Brzoska et al. 168 Brzoska and Stecka, 2007; Brzoska et al., 2007). Lactic acid bacteria act by colonizing different parts of the digestive tract, living in symbiosis with birds and stimulating their immune system (Dalloul et al., 2003; Huang et al., 2004; Koenen et al., 2004). Low-molecule organic acids acidify the digestive tract, which is paralleled by bacterial synthesis of lactic acid. Probiotic bacteria synthesize bacteriocins that inhibit pathogenic bacteria by reducing the incidence of infections causing proliferation of these bacteria, and by limiting the production of endotoxins that cause diarrhoea and mortality in birds (Cleveland et al., 2001). Probiotic bacteria are lactic acid bacteria belonging to the genera Lactobacillus Spp., Enteroccocus Spp., Streptoccocus Spp. and Bacillus Spp. Although many strains of lactic acid bacteria have been patented and put into production. Research is underway to obtain new bacteria characterized by more efficient synthesis of lactic acid and more efficient effect on broilers. To date, probiotic lactic acid bacteria were selected from diverse materials such as digestive contents of infants and animals or fermented dairy products. Most preparations contain Lactobacilus Spp. (including L. acidophilus) and Enterococcus Spp. bacteria. Several strains of Pediococcus Spp. with potential probiotic properties were obtained recently. These bacteria were assumed to show probiotic effects because of the rate of glucose metabolism. Several years' research on use of lactic acid bacteria in broiler chicken nutrition in our facility leads us to believe that the meat of chickens receiving probiotic bacteria has better taste compared to that of unsupplemented control chickens. It is our hypothesis that probiotic bacteria may change some physical characteristics of poultry meat such as aroma, juiciness and tenderness, which results in better sensory score of muscle tissue. The aim of this study was to determine if the Pediococcus Spp. probiotic bacteria fed to chickens can change their body weight, feed conversion, mortality, proportion of valuable cuts in the carcass, as well as palatability and physicochemical and sensory characteristics of meat. material and methods A total of 608 Ross 1-day-old unsexed broiler chickens were randomly allotted to 4 groups, with 4 replications of 38 birds per group. Chickens were kept in cages with sawdust floors, stocking density was 18 birds/m2 and 35 kg of birds/m2 at the end of the trial. Broilers were fed maize, wheat and soybean meal diets to 42 days of age (Table 1). The nutrient content of feed was estimated by chemical analysis (AOAC, 1990). The control group received a diet without probiotic bacteria (Negative control) and a diet with Lactobacillus acidophilus 842 (Positive control). The experimental groups received diets supplemented with Pediococcus Spp. 841 and Pediococcus Spp. 840, respectively. All groups received oligosaccharides (BIOMOS; 1 g/kg feed) and fumaric acid (FUA; ORRFA-Polska Sp. z o.o.; 9.0 g/kg feed). The bacteria were used at a rate of 3 million bacterial cells/bird/day. LAB were added to drinking water. The probiotic bacteria originated from the collection of the Institute of Agricultural and Food Biotechnology in Warsaw. Pediococcus Spp. in broiler chicken feeds 169 Table 1. Components and nutritive value of the feeds