Mastitis in dairy cows is mostly caused by pathogenic microorganisms, mainly Streptococcus, Staphylococcus, Enterobacter, Corynebacterium pyogenes, or pathogens of some infectious diseases, such as actinomycetes, Mycobacterium tuberculosis, foot-and-mouth disease virus, etc., which invade the breast through papillary ducts, lymphatic vessels or blood vessels. Poor sanitation in cowshed, nipple trauma caused by sagging breasts, endless milking, high vacuum of milking machine and long-term empty suction can all promote the occurrence of this disease. In addition, when drying milk, the imbalance of hormone regulation in the body will also lead to the onset.

Cow mastitis can be divided into clinical (dominant) mastitis and subclinical (recessive) mastitis.

Clinical mastitis includes acute mastitis and chronic mastitis.

(1) Acute mastitis: redness, swelling, heat and pain of different degrees suddenly appeared in the sick breast room. The milk yield is obviously reduced. The milk turns thin and yellow, and flocs appear. Severe cases are often accompanied by systemic symptoms, such as mental fatigue, loss of appetite, and elevated body temperature. The most serious is necrotizing mastitis, that is, a dark and cold necrotic area appears on the skin of the sick breast room, which gradually becomes larger and flows out a lot of pus, and finally the substantial part of the whole breast room falls off from the necrotic cavity.

(2) Chronic mastitis: Except that the milk is yellow, sticky and flocculent in different degrees, the elasticity of the sick milk room is often reduced or there are lumps of different sizes, which generally have no systemic symptoms.

Cows with subclinical mastitis have no abnormal appearance in milk, but the number of bacteria in milk is greatly increased, the pH value is increased, and the amount of dry matter (protein, fat) is reduced. Once improperly managed, it is easy to turn into clinical mastitis.

Treatment of mastitis: If only the first few handfuls of milk are flocculent, the breasts are not hard and the milk is milky white, it is necessary to massage more and milk as much as possible. If there are many flocs in the milk, the milk is grayish white and there are lumps in the breast, antibiotics are used for treatment. The treatment method is:

(1) Penicillin 800,000 ~1.6,000 units, streptomycin 1 g, and 20 ml of sterilized water were injected into the sick breast room with mammary duct, three times a day.

(2) Dissolve 1.6 million ~ 2.4 million units of penicillin in 50 ~ 100 ml of 0.5% procaine hydrochloride injection, and perform closed injection treatment at 2 ~ 4 points at the base of the sick breast room, repeating 1 time every 2 ~ 3 days.

(3) For mastitis caused by hormone imbalance in dry milk, progesterone 100 mg can be injected intramuscularly 1 time, and repeated injection 1 time several days later.

(4) Necrotizing mastitis can be treated with high-dose antibiotics such as penicillin, streptomycin, tetracycline and erythromycin, but the effect is often poor. When the whole sick milk room falls off, it should be washed with disinfectants such as 0. 1% potassium permanganate solution, once a day. Breast skin usually grows up in about half a month. The milk yield of other milk rooms increased significantly.