Calcium propionate is an artificially synthesized organic salt with strong inhibitory and bactericidal activity against bacterial and mold growth. Calcium propionate is listed as a feed additive in China and is suitable for all farmed animals. As an organic acid salt, calcium propionate is not only used as a preservative, but also frequently used as an acidifier and functional nutritional additive in feed, playing a positive role in improving animal production performance. Especially for ruminants, calcium propionate can provide propionic acid and calcium, participate in body metabolism, improve metabolic diseases in ruminants, and promote production performance.
Cows are prone to a lack of propionic acid and calcium after calving, which can lead to milk fever and a decrease in milk production and feed intake. Lactogenic fever, also known as postpartum paralysis, is mainly caused by a significant decrease in postpartum blood calcium levels in cows. It is a common nutritional and metabolic disease in cows during the perinatal period. The direct cause is that at the beginning of lactation, intestinal absorption and bone calcium mobilization cannot timely supplement the loss of blood calcium, and a large amount of blood calcium is secreted into the milk, leading to a decrease in blood calcium levels and causing postpartum paralysis in cows. Milk fever occurs mostly in high-yielding multiparous cows. With the increase of parity and lactation capacity of cows, the incidence rate of milk fever increases continuously.
Both clinical and subclinical milk fever can reduce the production performance of cows, increase the incidence rate of other postpartum diseases, reduce the reproductive performance and increase the death rate. Improving bone calcium mobilization and gastrointestinal calcium absorption through various measures from pre partum to pre calving is an important measure to prevent postpartum fever. Among them, low calcium diets and anionic diets (diets that lead to blood and urine acidity) in the early stages of perinatal production, as well as calcium supplementation after calving, are common methods to reduce the occurrence of milk fever.
Monitoring blood calcium levels is the most basic method for diagnosing milk fever:
When the blood calcium level is less than 2.0mmol/L, it is diagnosed as subclinical milk fever;
When the blood calcium level is less than 1.5mmol/L, it is diagnosed as clinical milk fever.
(Note: The normal blood calcium level of cows is 2.0-2.5mmol/L)