The effect of vitamin D on pigs

Vitamin D is closely related to the absorption and utilization of calcium and phosphorus. Only with the participation of vitamin D, calcium and phosphorus can play a role in the process of constituting tissues such as bones and teeth. Otherwise, even if the content of calcium and phosphorus is rich, the proportion is appropriate. The utilization rate is also greatly reduced. Because vitamin D can promote the absorption of calcium in the intestine, it prevents calcium ions in the blood from being discharged from the large intestine wall, thereby maintaining normal blood calcium levels and promoting calcium deposition in bones. At the same time, vitamin D has the effect of blocking calcium from the kidneys and storing it in the body. Long-term lack of vitamin D can hinder the absorption and metabolism of calcium and phosphorus, causing bone calcification insufficiency, causing piglets to suffer from rickets, causing skeletal inorganic salts to dissolve in adult pigs and suffering from rickets.

When pregnant sows are seriously deficient in vitamin D, not only do the piglets born have weak constitution and are prone to rickets, but they also give birth to deformed piglets. Generally, the content of vitamin D in green fodder is very low, and some feeds even contain almost no vitamin D, such as grass, roots and cereals. However, most plant-based feeds contain ergosterol. After harvesting, ergosterol can be converted into vitamin D by ultraviolet radiation in sunlight. Therefore, the amount of vitamin D in the hay made by sunlight is high. Animal feed cod liver oil and liver powder have the most abundant vitamin D content. In addition, there is a small amount of 7-dehydrocholesterol in the skin of pigs, which is higher than other livestock and can be converted into vitamin D3 by ultraviolet radiation in sunlight. The most effective and simple way to prevent vitamin D deficiency in pigs is to let the pigs basking in the sun. This is especially important for pregnant sows, lactating sows and piglets.