نوع مقاله : مقاله کامل
نویسندگان
1 علوم دامی- دانشکده کشاورزی- دانشگاه فردوسی مشهد- مشهد-ایران
2 علوم دامی- دانشکده کشاورزی- دانشگاه فردوسی مشهد- مشهد- ایران
چکیده
کلیدواژهها
موضوعات
عنوان مقاله [English]
نویسندگان [English]
Introduction and Aim: The improvement of digestibility plays an important role on enhancement of feeding efficiency in poultry. Bacteria produce beneficial enzymes that help to digest food. The use of bacteria to increase the digestion and absorption of feed nutrients was investigated in this study. Methods: Enzyme activity of 46 bacterial strains isolated from digestive system of broiler chickens and rumen of dairy cattle was tested by well diffusion method on solid medium containing the enzyme substrate. The bacteria with the highest enzyme activity were isolated and examined for dietary digestibility under different treatments. Food digestibility was measured by collecting the whole feces in Arian breed chickens. Results: The findings showed that rumen bacteria effectively secrete amylase, protease, cellulase, phytase and pectinase enzymes. None of Lactobacillus bacteria isolated from digestive system of chickens could produce cellulase and pectinase but some of them effectively exhibited lipase and xylanase activity that were used in 9 treatments containing different bacterial consortiums. In digestibility experiment, composition of isolates significantly affected nutrient digestibility in chickens, so as treatment 6 showed the highest digestibility for dry matter and starch and suitable performance in lipase activity. Conclusion: According to the results, Lactobacillus bacteria exhibited the ability to produce lipase and xylanase enzymes. However, bacteria isolated from Holstein cows’ rumen showed the ability to produce cellulose and pectinase, and lacked the ability to produce lipase. In addition, amylase, phytase, cellulase and lipase enzymes, produced and released by bacterial consortiums effectively broke down the nutrients in the feed, which led to improved nutrient digestibility. So, among the treatments under study, treatments 5 and 6 displayed the best performance compared to the other treatments regarding digestibility in broilers, and formed suitable consortium.
کلیدواژهها [English]
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