Adding enzyme preparations to increase fish feed utilization

Feed enzyme preparation is a kind of environment-friendly green feed additive with no residue, no pollution and no pollution. Due to the high protein content of fish feed, even though fish have a high rate of digestion and absorption of proteins (78% to 90%), endogenous proteases are not yet fully functional. After the addition of exogenous proteases, they can be remedied. The deficiency of the source-derived protease increases the digestion and absorption rate of the protein by about 10%, thereby saving protein.

Sugars are cheaper feed ingredients. Although the digestion and absorption rate of starch by fish is very low, in order to ensure feed safety and reduce feed costs, the amount of sugar added in feed is still 20% to 50%. . After the addition of amylase and glucoamylase, it can supplement the severely deficient amylase in fish and increase the digestion and absorption rate of starch from 20% to 40% to 80% so as to increase feed energy, improve feed utilization and reduce protein as energy. Consumption, lower feed costs and other purposes.

Fish is a unique group in the animal classification. The vast majority of fish are low-grade vertebrates and live in water all their lives, forming a unique digestive physiology that is different from that of livestock. The digestive system of fish is not as good as livestock and poultry, and endogenous enzymes are not as complete as livestock and poultry, affecting the digestion and absorption of nutrients in feed and requiring the addition of exogenous enzymes to assist digestion.

Most of the fish have no stomach, only the digestive tract. Gastrointestinal fish have a neutral digestive environment such as carp or alkaline. Adding exogenous enzymes to fish feeds requires careful adaptation to the neutral base. Environmental conditions of enzymes.

The fish lives in water for life. Because of the buoyancy of the water, it consumes less energy and can save energy substances in the feed. However, the demand for protein is high, and the suitable energy-protein ratio is 31-60 kJ/g. Digestion and absorption of carbohydrates by fish is low, and the digestibility of carbohydrates is also different with different dietary habits. Carnivorous fish (carp, carp) are 30% to 40%, omnivorous fish carp and carp are 60%, herbivorous fish grass carp, group head lice in more than 70%. From the perspective of endogenous amylase activity, the highest order was herbivorous fish> omnivorous fish> carnivorous fish. The digestive tract of fish contains no xylanase, and the protease activity is relatively low. It has no decomposition ability to cellulose and must add the corresponding exogenous enzyme.

The study found that the application advantages of feed enzymes in fish feed are mainly reflected in the following 10 aspects: 1 to promote fish growth, the growth rate can be increased by 8% to 16%; 2 to supplement the deficiency of endogenous enzymes, improve the fish itself Intestinal enzyme effects, improve the digestion and absorption rate of nutrients, participate in cell wall degradation, make full contact of the enzyme with the substrate, enhance the digestion of existing nutrients, improve the feed conversion rate; 3 improve the disease resistance of fish and improve its survival Rate; 4 improve the uniformity of groups; 5 change the composition of fish tissue; 6 reduce the stress response of fish, reduce the adverse effects of fish under adverse environmental conditions on its performance; 7 change the distribution of bacteria within the digestive tract of fish; 8 Reduce the contamination of fish manure and improve the culture environment; 9 Reduce the viscosity of fish digestive tract contents; 10 Elimination of anti-nutritional factors.