Analysis of the role of vitamins in pig breeding

As a big country in the pig breeding industry, China has a large proportion of live pigs in the world. The health and production performance of pigs are closely related to the quality of feed. Vitamins are easily overlooked as a trace element, but they are crucial to the health of pigs and are also indispensable nutrients for maintaining the physiological functions of pigs. If the pig body lacks vitamins, it will lead to corresponding deficiency, which will not only lead to physiological and metabolic disorders of pigs, but also affect the quality of pork and reproductive performance. Some vitamins can be synthesized by the body itself, while others must be obtained from the diet. This paper analyzes the role of several common vitamins (vitamin A, vitamin D and vitamin E) in the growth and development of pigs, in order to attract the attention of farmers and ensure the health of pigs.
1 Effects of Vitamins on Animal Physiological Functions
1.1 Vitamin A Vitamin
A has an important function of maintaining animal vision. If it is severely deficient, it will lead to functional night blindness. It is also one of the trace substances necessary to participate in the metabolism of protein, fat and carbohydrates in animals. . It plays an important role in maintaining high immunity and resistance of animals. When vitamin A is deficient, it will affect the production of related antibodies in the animal body and affect its health level.
1.2 Vitamin D
regulates calcium and phosphorus metabolism in animals is one of the most important physiological functions of vitamin D, especially by promoting the formation of calcium-binding protein to promote the absorption of calcium and phosphorus in the gastrointestinal tract and increase its utilization efficiency. Vitamin D also regulates the immune system of animals, helps to increase the level of related antibodies in animals, and enhances the body's immunity. Appropriate amounts of vitamin D can improve the reproductive performance of animals in the form of transport through the placenta, and act on the fetus through the mother. Vitamin D also plays a role in improving meat quality, helping to improve meat quality.
1.3 Vitamin E
Vitamin E, also known as tocopherol, can enhance animal immunity and resistance, improve antioxidant capacity and improve animal production performance. Vitamin E achieves the function of enhancing animal immunity and resistance by increasing the body's antibody concentration and strengthening cellular immunity. The concentration of vitamin E contained in the mitochondria and microsomes in animal tissues is increased, so that the stability of the subcellular membrane structure is improved when the antioxidant reaction occurs, thereby achieving the purpose of enhancing the antioxidant capacity of animals. The improvement of animal production performance by vitamin E is mainly reflected in that it can significantly improve its cold resistance, and can improve the damage caused by adverse factors such as heat stress to the body.
2 Effects on pigs
Feed factors, housing environment factors, breed genetic factors, etc. will all have an impact on the performance of pigs, and some influencing factors can be improved through external adjustments, among which the addition and improvement of vitamins in the feed can affect the performance of pigs. Both reproductive performance and meat quality are affected.
2.1 Reproductive performance
2.1.1 Vitamin A affects the reproductive performance of pigs.
When multiparous sows lack vitamin A, it is easy to cause sows to be in oestrus, ovulation cycle is not fixed, and the pregnancy rate is low. Occurrence of absorption, miscarriage, deformed fetus or stillbirth. When boars lack vitamin A, it will lead to decline of sexual function, lower quality of semen, low fertilization rate, etc. By studying the effect of vitamin A on the early development of porcine oocytes and embryos, it was found that when the concentration of vitamin A added to the medium was 20 μg/mL, the in vitro maturation rate of oocytes, the cleavage rate of embryos, the cyst Embryo rate and other indicators were significantly increased, and the multifunctionality and cell number of blastocysts were also significantly increased, indicating that an appropriate amount of vitamin A can improve the reproductive performance of sows.
2.1.2 The effect of vitamin D on the reproductive performance of pigs
The concentration of vitamin D affects spermatogenesis and maturation by affecting the expression of vitamin D receptors and related vitamin D metabolic enzymes in boar reproductive organs, and the form of added vitamin D has different effects on the reproductive performance of boars. Studies have shown that the concentration and form of vitamin D3 added in the feed have an impact on the quality of boar semen. When the concentration of vitamin D3 in the feed was 2 000 IU/kg, the indicators of sperm motility, effective sperm count, sperm acrosome integrity rate and plasma membrane integrity rate of boars were significantly higher than those in the group with the concentration of 200 IU/kg. In addition, the speed of sperm movement curve, linear speed and path speed were also significantly improved. It shows that when the concentration of vitamin D3 added in the feed is 2 000 IU/kg, the reproductive performance of boars can be significantly improved. When the form of vitamin D added in the feed was 25-hydroxyvitamin D3 (25-OHD3), the indicators of boar sperm motility, sperm linear motion speed, acrosome integrity and effective sperm count were significantly higher than those with vitamin D3. form of the added group, and the deformity rate of sperm was significantly reduced. It shows that when vitamin D in the feed is added in the form of 25-OHD3, it can more effectively improve the reproductive performance of boars from the aspects of improving sperm morphology and motility.
2.1.3 The effect of vitamin E on the reproductive performance of pigs
The antioxidant function of vitamin E is mainly achieved by regulating the body's enzyme system to ensure the normal function of the endocrine system. Vitamin E is also involved in the growth and development of embryos. If pregnant sows lack vitamin E, it may lead to early death of embryos, and at the same time increase the probability of weak fetuses and stillbirths in sows. If boar vitamin E is deficient, it will lead to the development of boar testes, spermatogenesis, development, etc. will be affected. Adding 220 IU/kg of vitamin E to piglets’ diets from weaning to 18 months of age can reduce the concentration of prostaglandins in the prostate and seminal vesicles, indicating that boars have a strong sexual desire at this time, and glutathione The activity of peptide peroxidase in testis and sperm cells was also significantly increased, indicating that the antioxidant capacity of boar reproductive organs was enhanced. Adding 60 IU/kg of vitamin E to the boar's diet can improve the adverse effects of heat stress on boars, especially to ensure the normal function of testicular Leydig cells, so that the quality of semen and the reproductive system of boars remain normal and stable. Another study found that adding vitamin E to boar diets for 7 weeks can effectively inhibit lipid peroxidation of sperm and significantly increase the number of sperm. It shows that vitamin E plays a positive role in improving the reproductive performance of boars.
2.2 Impact on meat quality
Meat quality is affected by many factors, such as genetic factors, feed nutrition factors, and slaughtering and processing techniques, among which oxidative deterioration is most likely to occur in the processing, slaughtering and storage stages, and some vitamins have anti-oxidation effects. Appropriate addition can improve pork quality.
2.2.1 The effect of vitamin A on meat quality
Vitamin A can achieve the purpose of improving pork quality when the dietary protein concentration is too low by regulating fat metabolism. Studies have shown that adding vitamin A at a concentration level of 3 000 and 6 000 IU/kg to the low-protein diet of fattening pigs, the results found that the growth performance and slaughter performance of fattening pigs after adding vitamin A did not change significantly, but after slaughter The protein content in the longissimus dorsi muscle was significantly increased, and the saturated fatty acid content was significantly reduced.
2.2.2 The effect of vitamin D on meat quality
The main physiological function of vitamin D is to promote the absorption and deposition of calcium and phosphorus. Therefore, by increasing the calcium concentration in the muscle, the protein decomposition of pigs after slaughter can be changed, thereby improving the tenderness of pork and making pork tender to a certain extent. The color and water retention are improved. Adding vitamin D3 (40 000 IU/kg) to the diet of fattening pigs before slaughter can slow down the decline of muscle pH after slaughter, and can improve the tenderness of pork by increasing the calcium content in muscle. Adding 500,000 IU/kg of vitamin D3 to the diet of pigs, when testing the quality of pork 7 and 14 days after slaughter, it was found that the brightness value of the tenderloin decreased significantly while the red value increased significantly. This result shows that in the feed Adding vitamin D3 can improve the color of slaughtered pork to a certain extent.
2.2.3 The effect of vitamin E on meat quality
Vitamin E has the effect of anti-oxidative stress, and can alleviate the oxidative deterioration of meat quality by preventing fat oxidation. Add 0, 100, 200 IU/kg vitamin E to the diet of hybrid fattening pigs, and study its effect on pork quality. The addition group; the fading rate after 24 hours of refrigerated storage was significantly less than that of the no-addition group, the hydraulic power of the system was significantly improved, and the drip loss was reduced, but the pH did not change significantly. The changes of these indicators all indicate that adding vitamin E to the feed can significantly improve the quality of pork and increase its competitiveness in the consumer market.
3 Summary
Vitamin  is an essential nutrient in the growth and development of pigs. Although the demand is small, it plays an important role, especially for the reproductive performance and meat quality of pigs. Therefore, adding an appropriate amount of vitamins in the feed can effectively improve the production performance of pigs. Under the condition of fully ensuring the health of pigs, improve reproductive performance, gradually expand the production scale of the farm, and produce high-quality pork. Get the favor of consumers and improve market competitiveness.