Types of Feed Additives for Dairy cows

At the present stage, the dairy industry in China has developed greatly. with the continuous expansion of the scale of dairy farming, farmers pay more and more attention to the production performance and health status of dairy cows, such as milk yield, milk fat rate and so on. Dairy cow feed additives play an obvious role in increasing milk production, improving milk composition and reducing milk production stress.

Silage additive

Some additives are often added in the process of silage to improve the quality and palatability of silage. Commonly used additives are: non-protein nitrogen, enzyme preparations, bacterial inoculants and preservatives. The main non-protein nitrogen preparations are urea and ammonia sulfate. After adding non-protein nitrogen, the color and smell of silage are worse, but feeding cattle with this material can increase milk yield and milk fat content. The addition of compound enzyme preparation could significantly improve the fermentation quality of silage rice straw, and the effect of wheat bran (60.9%) and compound enzyme (1.3g / kg DM) was the best. The addition of lactic acid bacteria could increase the lactic acid content and reduce the acetic acid content in corn silage. For alfalfa silage, it could significantly reduce the pH value, butyric acid and ammonia nitrogen content, and improve the silage quality. The fermentation broth of green juice developed in recent years, as a pure natural inoculant of lactic acid bacteria, can make wild lactic acid bacteria multiply in large numbers and show higher fermentation stability under anaerobic conditions. The addition of formic acid preservatives can significantly improve the effective degradation rate of dry matter crude protein neutral detergent fiber and acid detergent fiber in alfalfa silage.

Choline

Choline is usually classified as B vitamins. Natural choline generally exists in feed materials, but its content varies with different cultivation conditions. Most animals have the ability to synthesize choline, but this ability is affected by the activity of enzymes related to choline synthesis and decomposition in animals. In the nutrition of dairy cows, the roles of choline include minimizing the incidence of fatty liver, improving nerve conduction and acting as a methyl donor. The addition of choline also has the effect of saving methionine, otherwise, methionine in feed will be used for the synthesis of choline. Animals lack choline, there will be respiratory disorders, behavioral disorders, loss of appetite, slow growth and other symptoms.

Amino acid additives

Recent studies have shown that dairy cows also have the problem of amino acid imbalance in the small intestine, mainly because lysine and methionine can not meet the needs of dairy cows. By changing the amino acid pattern of small intestine, the production performance and protein utilization of ruminants can be improved. The requirement for dairy cows to maintain digestible amino acids in the small intestine is 2.3 g / W 0.75, and the amount of digestible amino acids in the small intestine per kilogram of milk (containing 3.0-3.3% crude protein) is 41-45 grams. For high-yield dairy cows with daily milk production of more than 30 kg, the lowest requirements for methionine and methionine are 6.5% and 2.0% of the total digestible amino acids in the small intestine, respectively. Because of the degradation of amino acids by rumen microorganisms, the protected products must be selected to supplement amino acids to dairy cows. At present, there have been rumen-protected lysine and methionine products on the market.

Feed enzyme preparation

Enzyme is a kind of biocatalyst produced by activated cells and catalyzes specific biochemical reactions. Enzyme preparation is a kind of biological product with catalytic function after enzyme purification and processing. Feed enzyme preparation refers to the enzyme preparation added to animal diet in order to improve the digestion and utilization of nutrients, reduce anti-nutritional factors or produce functional components that have special effects on animals.

1. Single enzyme preparation: it is divided into digestive enzyme (amylase, Glucoamylase, protease, lipase) preparation and non-digestive enzyme (cellulase, hemicellulase, Pectinase) preparation.

2. Compound enzyme preparation: at present, using enzyme preparation to improve the digestion and utilization rate of feed raw materials is of great significance to solve the serious shortage of feed raw material resources and reduce environmental pollution in our country. If enzyme preparation was added to calf diet the digestibility of starch and crude protein could be significantly increased and the daily gain could be significantly increased and the diarrhea rate could be reduced by adding compound enzyme preparation. When adult cattle and adult cattle were fed with cellulase, the feed intake of roughage increased by 810%, the nitrogen in feces decreased by 30% from the initial to 70% after a week, and the nitrogen content in urine decreased by 60%. When 53 g / (per day) of cellulase compound enzyme was added to the diet of dairy cows, the average daily milk yield of dairy cows increased by 4.5%, and the ratio of milk to feed decreased by 4.32%, which had no effect on milk composition.

Yeast culture

The yeast culture is a mixture of living yeast cells and the medium used to culture yeast. Aspergillus oryzae and Saccharomyces cerevisiae are commonly used in the preparation of yeast culture at home and abroad. Yeast culture can stimulate the reproduction of rumen cellulose bacteria and lactic acid bacteria, change the mode of rumen fermentation, reduce rumen ammonia concentration, increase microbial protein production and feed digestibility. Under the condition of heat stress, the addition of yeast culture to the diet could reduce the rectal temperature of dairy cows. The addition of yeast culture to the diet of dairy cows could increase the daily milk yield by 1-1.5 kg, and the percentage of milk fat and milk protein were also increased in different degrees.

Living bacteria preparation

Live bacterial preparation, also known as direct feeding microorganism, is a kind of living microbiological preparation which can maintain the balance of gastrointestinal microflora of animals. There are mainly Bacillus, Bifidobacterium, Streptococcus, Bacteroides, Digestive cocci and so on. The dosage forms of live bacterial preparations include powder, pill, paste, liquid and so on. The application of live bacteria preparation in dairy cows can increase milk yield by 30.8%, reduce stress and enhance disease resistance.

Rumen element

Rumin, also known as monensin, is a polyether antibiotic, which is commonly used to change the type of rumen fermentation. It was first applied to beef cattle, and the experiments on adult cattle and first-born cows showed that it could increase the weight gain by 614%, but had no adverse effect on reproductive performance, calving process and birth weight of calves. Due to the accelerated growth rate, young cows can breed and calve ahead of time, thus saving a lot of feed costs. Application in dairy cows can reduce the production of acetic acid, butyric acid and methane in rumen, increase the production of propionic acid, synthesize more glucose, and provide more precursors for lactose synthesis, thus increasing milk yield of dairy cows. The mechanism of ruminin improving the production performance of ruminants is related to the change of the proportion of volatile acid production in rumen and the reduction of methane production. The reaction in production is to improve feed conversion efficiency, reduce heat consumption, alleviate heat stress, save protein, change rumen fullness and rumen chyme outflow rate.

Rumen buffer

Due to the large concentrate feed intake of high-yield dairy cows during the whole lactation period, it is necessary to add appropriate buffers such as baking soda and magnesium oxide to the diet to improve feed intake, milk yield and milk composition of high-yield dairy cows and maintain cow health. reduce the occurrence of rumen poisoning, regulate and improve the effect of rumen microbial fermentation.

1. Baking soda: feeding baking soda to high-yield dairy cows during peak lactation has a significant effect on the prevention of metabolic diseases such as diabetes and rumen poisoning. Especially if the cattle with high silage and concentrate are fed all the year round, the effect is better. Cows begin to be replenished after calving, and by the end of the lactation period, the supplementary feeding amount is 1.5% of the concentrate amount, that is, 150 grams of 200 grams of baking soda is mixed in every 10 kg of feed, not alone.

2. Magnesium oxide: 0.2-0.4% of dietary dry matter weight or 0.3-0.6% of concentrate dosage, or 2-3 parts of sodium bicarbonate mixed with 1 part of magnesium oxide, 0.6-0.8% of dietary dry matter or 1.6-2.6% of concentrate amount.

Anti-stress agent

Stress is an emergency response of dairy cows to adverse stimuli such as transportation, preventive immunity, high temperature, humidity, cold, calving, lactation and so on. High-yield dairy cows are sensitive to stress such as high temperature, cold, delivery and lactation. Therefore, before the occurrence of the above situation, the contents of manganese, iron, copper, zinc, iodine and cobalt in the diet should be increased by about twice as much as the normal level, which can effectively enhance the anti-stress ability of high-yielding dairy cows. In recent years, it has been found that organic chromium (chromium picolinate) has good anti-stress effect on high-yield dairy cows, but also can improve energy metabolism, increase the utilization rate of manganese, iron, copper and zinc, and activate the activity of many kinds of enzymes. the suitable adding concentration is 0.2 mg of chromium per kg.

Ectopic acids

Adding 1% heterotopic acid additives to the concentrate of high-yield dairy cows can significantly increase milk yield, milk fat rate and feed conversion efficiency. These substances mainly include isovaleric acid, isobutyric acid and isocaproic acid.

Propylene glycol

The addition or direct administration of propylene glycol in the diet of high-yield dairy cows, such as propylene glycol, ethylene propylene glycol, isopropanediol and so on, can effectively reduce and prevent the occurrence of ketosis.

Rare earth elements

Adding 40-45 mg rare earths to the concentrate of dairy cows can increase the daily milk yield of dairy cows by 1115%, increase milk fat rate, enhance disease resistance and prevent gastrointestinal diseases.

Zeolite

Zeolite is boiling when heated at high temperature, so it is called zeolite. For dairy cows, zeolite can adsorb harmful gases in the gastrointestinal tract, and slowly release the adsorbed ammonia ions for rumen synthesis of bacterial protein, increasing the production and deposition of animal protein. In addition, zeolite can enhance the enzyme of the body and improve the utilization of crude fiber by rumen microorganisms. Adding 40.7% zeolite to the cow concentrate can increase the milk yield by about 8%.