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Carbohydrases, namely xylanases and beta-glucanases, are widely used in animal nutrition for modification of NSPs to improve the quality of feeds and productivity of animals. Хylanases are inhibited by plant proteins like TAXI, XIP, and PGIP, while 1,3-- and 1,4- endoglucanases are less affected by plant inhibitors. Recombinant strain development with optimized xylanase and endoglucanase composition suitable for local cereal diets and applied animal tests with chicken and pigs. The design and creation of well-balanced enzymatic complex of 1,4-b and 1,3-b endoglucanases and 1,4-b-endoxylanases with high molecular activity and low level of inhibition by cereal proteins. Endoglucanases and xylanase were expressed in Penicillium sp. host strain to give enzyme preparations with various Xyl/EG activities ratio. The strains were cultivated at lab-scale fermentation system for cultivation parameters optimization and development of post-fermentation steps. The best clones were selected for up-scale and industrial production of feed enzymes and animal testing. Testing of xylanase and endoglucanase enzyme preparations for application in chicken and pigs diets were performed with 210 chicken (Kobb) and 70 pigs (Yorkshire and Landrass). Chicken were feeded for 36 days with standard balanced chicken feed based on wheat (46-55%), corn (7-10%), soy and sunflower mix depending on the age. The dosage of enzyme preparations were 50 and 75 g per ton of feed. The addition of enzyme preparations with endoglucanase and xylanase activities lead to the increase of animal weight 4,71% and 5,66% after 21 days; 4,22 and 6,20% after 36 days for 50 and 75 g/ton of enzymes respectively. Pigs were feeded with standard balanced feed based on wheat, corn, and barley as carbohydrate source and soy and sunflower mix as protein source depending on the age. The dosage of enzyme preparations were 75 and 100 g per ton of feed. After 90 days from 4,3 to 8,8% increase in animal weight were reached for the groups feeded with xylanase and xylanase/endoglucanase enzyme prepaprtions at the dosage 75 and 100 g/ton respectively.