Dairy cow mastitis is one of the main diseases that endanger dairy farming. It exists in almost every farm, not only in China but also abroad. Dairy cow mastitis has become a worldwide problem. Dairy cows infected with mastitis not only affect the milk production of cows, but also affect the quality and quality of milk, and threaten the food safety of our human beings.
1. Effect on Milk Yield of Dairy Cows
When mastitis occurs in dairy cows, the mammary gland tissue will be damaged and destroyed to varying degrees. At the same time, to eliminate pathogenic bacteria, the body will produce a large number of immune cells, such as white blood cells and macrophages. When these cells gather together, they will block part of the mammary duct and make the milk unable to be discharged from the mammary duct. It results in temporary loss of function of some breast cells and permanent loss in severe cases, which leads to the decrease of milk production in dairy cows. Every occurrence of mastitis in dairy cattle will cause certain damage to breast and lactation function, and the decline of milk production is difficult or even unable to restore to the normal levels. The more the occurrence of mastitis, the more serious the damage to breast, the more the total amount of breast cells is reduced, the worse the lactation function, and milk production. The lower the quantity, therefore, if cows suffer from mastitis for a long time or frequently, it will affect the milk production of cows throughout their lives.
2. Effect on Milk Quality
After mastitis occurs in dairy cows, the number of bacteria in the body increases, which will destroy the nutritional facts of dairy cows, and make the nutritional distribution of milk change significantly, thus seriously affecting the quality of dairy products. The milk produced by cows with mastitis will also change in taste. The saltiness of milk will increase and produce bad gas. Sometimes it will lead to the sour taste of milk, and the shelf life of milk will be significantly shortened. Because of mastitis, the nutritional components of milk change, and the protein in the milk becomes easily decomposed by enzymes, which affects the processing cost and quality of dairy products.
Also, the white cells and macrophages in dairy cows kill pathogenic bacteria and leave the related enzymes behind. These enzymes are heat-resistant. When milk is heated to disinfect, these enzymes are resistant to heating and disinfection of milk, which damages the fat and protein in milk, thus reducing the quality of milk. In addition, when mastitis occurs in dairy cows, a large number of drugs will be used for treatment, among which antibiotics are commonly used, and antibiotics will remain in milk, so that the growth and reproduction of beneficial bacteria in milk, such as lactic acid bacteria, will be inhibited, the production of lactic acid will be blocked, affecting the production of dairy products.
3. Increase the cost of farming
When dairy cows suffer from mastitis, their mammary tissue cells will be damaged to varying degrees. When serious damage occurs, they will form spots or abscesses, or even necrosis, which will cause permanent damage to the mammary tissue, thus completely losing the lactation function. This has a more serious impact on high-yielding dairy cows, which will force many dairy cows at the peak of milk production to be eliminated, increasing the cost of herd replacement. Also, when cows suffer from mastitis, they are susceptible to a variety of pathogenic microorganisms and become the main source of infection during milking. Especially in the case of sharing a milking hall, it is very easy to spread diseases, which makes the whole cattle face the risk of elimination, which greatly increases the cost of cattle farming and causes extremely severe damage to dairy farming. Heavy economic losses.
When dairy cows suffer from mastitis, they need to be treated with drugs. Especially for chronic mastitis, the treatment period is longer and the cost is higher, which undoubtedly increases the cost of dairy cow breeding. Also, dairy cows need special management during the occurrence of mastitis, infectious mastitis also needs separate management, milking work also needs to be changed from machine to manual, which increases the labor force, resulting in increased costs in dairy farming management.
4. Influencing the Reproductive Performance of Dairy Cows
The occurrence of mastitis in dairy female cows will have a very adverse impact on their reproductive performance, which will lead to abnormal oestrus or no oestrus in cows, and reduce the fertility rate of cows. This is mainly due to the influence of the secretion of estrogen after mastitis in cows, the decrease in the level of estrogen, and the lack of lutein to stimulate ovulation, thus resulting in milk. Cattle can't oestrus on schedule, or the oestrus symptoms are not obvious and the best mating time is missed, which will reduce the fertility rate of mating, and sometimes lead to cows, not oestrus. This delayed the estrus cycle of cows. Also, if cows with mastitis succeed in conceiving, their abortion rate is also higher than that of normal cows. Studies have shown that cows with mastitis have three times as many abortions within 45 days of insemination as healthy cows.
5. Threatening human health
Some of the causes of mastitis in dairy cows are due to breast obstruction, which leads to the abnormal secretion of milk, while most of the reasons are caused by infection of pathogenic microorganisms, which results in the production of milk containing a large number of pathogenic microorganisms. For cows with recessive mastitis, this problem is easily ignored, if If these pathogenic microorganisms are not completely destroyed in the process of milk processing, they will remain in the milk products, and some pathogenic bacteria belong to zoonotic pathogens, which will inevitably bring great harm to people's health.
In addition, antibiotics and other drugs will be used in the treatment of dairy cows suffering from mastitis. For intractable mastitis or chronic mastitis, the treatment cycle is longer and the use time of drugs is longer, which will lead to a large number of antibiotics remaining in the breast, and some of these antibiotics will not be eliminated in the process of processing and sterilization of dairy products. When people eat this kind of milk or milk products, they may have some adverse reactions, such as allergic reactions, poisoning reactions, and even cause anaphylactic shock and death. In addition, people may become resistant to some drugs after long-term consumption of milk containing drug residues, which has a great impact on the prevention and treatment of diseases in the future.