Salt contains sodium and chlorine, and salt is often used to supplement the deficiency of sodium and chlorine.
Sodium plays an important role in maintaining the acid-base balance in the body, maintaining the normal osmotic pressure of body fluids and regulating the volume of body fluids. Sodium ions are excreted with saliva in the form of bicarbonate, which can inhibit the rumen, reticulum and flap stomach of ruminants from producing too much acid and create suitable environmental conditions for rumen microbial activities. Chlorine and sodium cooperate to maintain the osmotic pressure of extracellular fluid, participate in the formation of gastric acid and ensure the necessary pH value of pepsin.
In order to supplement nutrition, improve the production performance of beef cattle, improve feed utilization rate, improve feed quality, promote the growth and reproduction of beef cattle, and ensure the health of beef cattle, adding a small amount or trace of nutrients or non-nutrients into feed is called feed additive. Commonly used cattle feed additives mainly include: macroelement (mineral) additives, such as calcium, phosphorus, sodium, chlorine, magnesium and so on. Vitamin additives, such as vitamin A, vitamin D, vitamin E, nicotinic acid, etc. Trace element additives, such as iron, zinc, copper, manganese, iodine, diamond, selenium, etc. Amino acid additives such as protective lysine and methionine; Rumen buffer regulator, such as sodium bicarbonate.
mineral
Salt can stimulate the secretion of saliva, promote the digestion of other digestive enzymes, improve the taste of feed and stimulate the appetite of animals. Lack and excess of sodium and chlorine will affect the production performance and health of beef cattle. Long-term salt deficiency in adult cattle diet can lead to loss of appetite, listlessness, malnutrition, rough coat, decreased milk production and productivity. Calf diet is short of salt for a long time, which is characterized by stagnant growth and reduced feed utilization rate. However, when the salt is seriously excessive, it will cause an increase in drinking water, diarrhea and poisoning. The feeding amount of salt should generally be 0.5% ~ 0.1%of concentrate; When the milk yield of beef cattle increases, the salt can be appropriately increased.
Calcium hydrogen phosphate and stone powder calcium hydrogen phosphate and stone powder calcium hydrogen phosphate are commonly used mineral feeds for beef cattle to supplement calcium and phosphorus. The feed grade standard of calcium hydrogen phosphate in China stipulates that the phosphorus content is not lower than 16%, the calcium content is not lower than 2 1%, and the fluorine content is not higher than 0. 18%.
Stone powder mainly refers to lime powder, which is a kind of natural calcium carbonate with a calcium content of 34% ~ 38%. It is the cheapest and most accessible mineral feed for calcium supplementation.
Insufficient calcium and phosphorus in adult cattle diet can lead to osteomalacia or osteoporosis, loss of appetite or food waste, ectopic addiction and decreased production performance. Cows have abnormal estrus, repeated infertility and reduced lactation. When calcium and phosphorus in calf diet are insufficient, rickets can be caused. At the initial stage of the disease, the symptoms are loss of appetite, listlessness, gradual weight loss, unkempt hair, lying down rather than standing up for activities and dyskinesia. With the development of the disease course, skeletal dysplasia and softening gradually appear, ossified tissue at the bone end becomes thicker, and the spine and sternum are bent and deformed.
In beef cattle and beef cattle, the calcium level in concentrated feed at different physiological stages is 0.9% ~ 1.2%, and the phosphorus level is 0.5% ~ 0.7%.
Vitamin and trace element additive premix
Vitamins are low molecular weight compounds necessary to maintain normal physiological functions of animals. Once vitamins are lacking in feed, it will cause physiological dysfunction of the body and various vitamin deficiencies. Therefore, vitamins are essential nutrients to maintain life.
There are many kinds of vitamins, which are usually divided into two categories according to their solubility, namely fat-soluble vitamins (vitamin A, vitamin D, vitamin E and vitamin K) and water-soluble vitamins (vitamin B and vitamin C).
Because rumen microorganisms can synthesize vitamin K and B vitamins, and liver and kidney can synthesize vitamin C, generally speaking, there is no need to add extra vitamins except calves. However, sufficient vitamin A, vitamin D and vitamin E must be provided in the diet to meet the needs of beef cattle and beef cattle in different physiological periods.
It is also reported that nicotinic acid plays an important role in nutritional metabolism and milk production of beef cattle. Generally, feeding 3-6 grams of nicotinic acid to each cow every day in the early lactation or before delivery can prevent ketosis in dairy cows and significantly improve milk yield. In summer, high-yield beef cattle can also increase milk production by increasing 6 grams of nicotinic acid per head every day.
The amount of vitamins added should be determined according to the nutritional needs of different varieties and different physiological periods. Insufficient and excessive vitamins have adverse effects on the health and production performance of cattle.
Lack of vitamin A will lead to the stagnation of calf growth and development, rough and dull fur, low pregnancy rate of dairy cows and postpartum uterus inflammation, which will seriously affect production performance. When vitamin D is deficient, osteochondrosis occurs in calves and osteoporosis occurs in adult cows. The main symptom of vitamin E deficiency is degeneration of calf skeletal muscle, which leads to dyskinesia and decreased reproductive rate of adult cattle.
Excessive vitamin addition will not only cause waste, but also cause poisoning. For example, excessive vitamin A can lead to loss of appetite, itchy skin, joint swelling and pain, hyperosteogeny and weight loss; Excessive vitamin D will lead to the increase of calcium in blood, the loss of calcium in bones and osteoporosis.
Trace elements Trace mineral elements commonly used as feed additives include iron, copper, manganese, zinc, selenium, iodine and cobalt, which play an irreplaceable role in the body. Iron, copper and cobalt are all indispensable elements for hematopoiesis and play a synergistic role; Manganese is a component of many enzymes involved in the metabolism of sugar, protein and fat, and is also one of the necessary components for the formation of chondroitin sulfate, which promotes the metabolism of calcium and phosphorus and the formation of bones. Iodine is an essential element for thyroid gland to form thyroxine. When iodine deficiency occurs, it is mainly manifested as goiter, decreased metabolic function, hindered growth and development, and loss of fertility. Zinc is a component of many enzymes and insulin in the body. Zinc mainly participates in various metabolic activities in the body through these enzymes and hormones. Selenium is a component of glutathione peroxidase. Glutathione can eliminate the toxic effect of lipid peroxide and protect cells and subcellular membranes from peroxide damage.
The compound premix is easy to cause poisoning because of the small amount of vitamins and trace elements added in the feed, which brings a lot of inconvenience to farmers.
In recent years, based on nutrition balance theory, electrolyte balance theory and nutrition immune regulation technology, Beijing Challenge Group has developed calf period, breeding period, lactation period and dry milk period of beef cattle according to the needs of beef cattle and beef cattle for various vitamins and trace elements in different physiological periods and abnormal situations such as stress, combined with mature and efficient feed additive application technology at home and abroad. 1% and 4% series products of beef cattle compound premix in cow period, fattening period and pregnancy period. Through the application in recent years, the results show that this series of premix can significantly improve the milk yield of beef cattle, increase the milk fat rate, prevent osteoporosis, increase the pregnancy rate, increase the feed conversion rate of beef cattle, increase daily weight gain, improve meat quality and reduce nutritional metabolic diseases.
buffer
The addition amounts of various buffers are as follows:
Sodium bicarbonate accounts for 0.7% ~ 1.5% of daily dry matter intake, or 1.4%~3.0% of concentrate.
Magnesium oxide accounts for 0.3% ~ 0.4% of daily dry matter intake, or 0.6% ~ 0.8% of concentrate.
Bentonite accounts for 0.6% ~ 0.8% of daily dry matter intake, or 1.2%~ 1.6% of concentrated feed.
The mixture of baking soda and magnesium oxide is better, accounting for about 0.8% of beef concentrate (baking soda accounts for 70% and magnesium oxide accounts for 30% in the mixture). High-yield beef cattle eat more concentrate, which is easy to increase rumen acidity, inhibit rumen microbial activity, cause digestive disorders, reduce milk fat rate and cause some related diseases. In order to prevent the occurrence of such diseases, buffer should be considered in the following situations: early lactation; Concentrate accounts for more than 50% in the diet; Roughage is almost all silage; In summer, the milk fat rate decreased significantly or the appetite of lactating cows decreased, and the dry matter intake decreased significantly; When concentrate and coarse materials are fed separately.
There are many kinds of buffers, mainly sodium bicarbonate (baking soda) and sodium carbonate (edible alkali), but magnesium oxide or bentonite should be added to high-yield beef cattle with daily milk output higher than 30 kg.