What are the three commonly used health-care feeds for laying ducks?
Commonly used health-care feeds for laying ducks include growth promoters (such as antibiotics, synthetic antibacterial drugs and enzyme preparations, etc.), deworming health-care agents (such as anticoccidial drugs), etc. Although they are not inherent nutritional components of feed and have no nutritional value themselves, they have effects such as inhibiting bacteria, resisting disease, maintaining body health, improving palatability, promoting growth and improving feed conversion.
????Chinese herbal medicine feed additives
As feed additives, Chinese herbal medicines have low toxic and side effects, are not easily residues in products, and contain various nutritional components and bioactive substances, having both nutritional and disease-preventing dual effects. Their natural, multifunctional and nutritional characteristics can play roles such as enhancing immunity, hormone-like, vitamin-like, anti-stress and anti-microbial effects, and have broad prospects for use.
?Feed enzyme additives
Enzymes are proteins with special functions synthesized by animal and plant bodies, and are also catalysts that promote the digestion of proteins, fats and carbohydrates, and participate in the biochemical reactions of various metabolic processes in the body. Adding enzyme preparations to duck feed can improve the digestibility of nutrients.
Commonly used feed enzyme additives include single enzyme preparations and compound enzyme preparations. Single enzyme preparations, such as α-amylase, β-glucanase, lipase, cellulase and phytase, etc.; compound enzyme preparations are made by using one or several single enzyme preparations as the main body, mixed with other single enzyme preparations, or obtained by fermentation of one or several microorganisms. Compound enzyme preparations can simultaneously degrade various substrates in feed that need to be degraded (various anti-nutritional factors and various nutrients), and can maximize the nutritional value of feed. Feed enzyme preparation products at home and abroad are mainly compound enzyme preparations, such as feed compound enzymes mainly based on protease and amylase.
Enzyme preparations are mainly used to supplement the insufficiency of endogenous enzymes in animals; feed compound enzyme preparations mainly based on glucanase are mainly used for feed with barley and oats as the main raw materials; feed compound enzymes mainly based on cellulase and pectinase mainly function to destroy plant cell walls, release nutrients in cells, make them easily acted upon by digestive enzymes, promote digestion and absorption, and can eliminate anti-nutritional factors in feed, promoting the digestion and absorption of animals; feed compound enzymes mainly based on cellulase, protease, amylase, saccharifying enzyme, glucanase and pectinase can combine the common effects of the above enzymes and have a stronger digestion-aiding effect. The dosage of enzyme preparations depends on the size of enzyme activity; different enzyme preparations have different activities, and the effect of supplementing enzyme preparations is related to the age of the animal.
Since the macro-mineral nutrient element most lacking in modern breeding industry and feed industry is phosphorus, but 70% of the phosphorus in crop seeds such as soybean meal, cottonseed meal, rapeseed meal, corn and bran is phytic acid phosphorus, which cannot be utilized by ducks and is excreted in feces in vain. This not only causes waste of resources and pollutes the environment, but phytic acid also exists as an anti-nutritional factor in the animal digestive tract, affecting the absorption of cations such as calcium, magnesium, potassium and iron and of protein, starch, fat and vitamins. Phytase can hydrolyze phytic acid (inositol hexaphosphate) and release absorbable available phosphorus, which not only eliminates the anti-nutritional factor and increases available phosphorus, but also improves the absorption and utilization rate of other antagonized nutrients.
?Microecological preparations
Microecological preparations, also called beneficial bacteria preparations or probiotics, are live bacteria preparations made by artificially screening and culturing beneficial microorganisms in animal bodies, then producing them industrially through modern bioengineering, and specially used for animal nutritional health care. They contain more than a dozen to several dozen kinds of beneficial bacteria in the gastrointestinal tract of livestock and poultry, such as Kato bacteria, effective microorganisms (EM), probiotics, etc., and there are also single bacteria preparations, such as lactic acid bacteria preparations. However, in the breeding industry, except for some special needs, compound preparations of multiple bacteria are used. In addition to being fed as feed additives and drinking water agents, they can also be used to ferment straw and duck manure to make bio-fermented feed, which not only improves the digestibility of roughage, but also turns waste into treasure and reduces pollution. After microecological preparations enter the digestive tract, they first establish and restore the dominant flora and microecological balance in the digestive tract, and produce some digestive bacteria, antibiotic-like substances and bioactive substances, thereby improving the digestibility of feed and reducing feed costs; inhibiting infections by harmful bacteria such as Escherichia coli, enhancing the body's disease resistance and immunity, and allowing less or no antibacterial drugs to be used; significantly improving the feeding environment, reducing odorous gases such as ammonia and hydrogen sulfide in duck houses by more than 70%.