Beware of necrotizing dermatitis in pigs in summer and autumn

I have never seen necrotic dermatitis in pigs. I thought it was an old disease and may have disappeared here. I didn't expect it to occur in a small @#@ farm in our county last July. The diagnosis and treatment are summarized as follows to remind farmers to pay attention to the prevention of this disease.

1 Condition

The normal stock of the pig farm was 70~80 pigs. Due to the poor pig market at that time, the owner of the farm had more pigs and reached 100 pigs. When the pig weight reached 60kg in July, it was found that some pigs had broken skin, itchy skin and scab, mainly on the buttocks, neck and side of the pig. At that time, the author suspected that it was caused by ectoparasites or mosquito bites, so he sprayed the whole group with Chulailing (main component phoxim) mixed with water. 2 days later, 1 pig died, the owner suspected that it was poisoned by leprosy, the author rushed to the pig farm, the dead pig had been buried, another 2 pigs had been seriously infected, and some parts of other pigs had been infected. 2 pigs with severe disease had depilation on neck, buttocks and sides of body, some of them had broken skin, some of them had greyish yellow and some of them had greyish brown fetid exudate, the size of broken wound was different, and the size of common wound was 1 yuan coin, and the wound bottom was uneven. There were more than 10 such necrotic foci in the two severely infected pigs and 4 - 5 in the slightly infected pigs.

2 Initial diagnosis and treatment

According to the symptoms, the location of the lesion, the special thick juice and odor, the preliminary diagnosis was necrotic dermatitis of pigs, caused by necrotic bacilli. It is suggested to strengthen heart, rehydrate and detoxify 2 seriously ill pigs immediately. Local treatment: wash the necrotic focus on the body surface of the sick pig with warm water, expose the necrotic focus with a brush, and then spray medical hydrogen peroxide (usually sold in pharmacies) onto the necrotic focus with a syringe to remove necrotic tissue, and then apply erythromycin ointment. Due to itching of sick pigs, they do not resist treatment. Symptomatic treatment, oxytetracycline hydrochloride injection, analgin injection, intramuscular injection, continuous 3 days later. 10% sulfadiazine sodium was injected intramuscularly 3 times a day for 3 days. For pigs, immediately isolate the sick pigs, disinfect the whole herd with Quanfu (main components of double-chain quaternary ammonium salts, iodine complexes, etc.), and mix with oxytetracycline tablets for prevention for 5 days.

3 Laboratory tests

Smears were taken from the junction of necrotic and healthy parts, and methylene blue staining was used for microscopic examination. The uneven staining of slender bacilli could be seen, and further diagnosis was made as necrotic bacilli disease.

4 Causes

Because the pig farm usually has only 70~80 pigs, but suddenly increased to 100 pigs, the pig activity site is too crowded; Moreover, the pig farm is in the wild, there are two artificial fish ponds nearby, there are too many mosquitoes; will reduce the resistance of pigs and cause disease in pigs.

5 Symptoms

Necrotic dermatitis occurred in this pig farm with obvious symptoms, mainly on the buttocks, neck and body side, characterized by necrosis and ulceration of skin surface and subcutaneous skin. Early onset due to local itching manifestations and ectoparasitism confused. On closer examination, nodules with dry scabs are seen, hard to the touch, swollen but without thermal pain. With the tissue necrosis under the eschar, the necrotic focus developed rapidly, and the necrotic focus had grayish yellow or grayish brown fetid liquid flowing out. The necrotic focus wound size was different, the edge was uneven, and the wound bottom was uneven. The ears or tails of individual sick pigs will become dry and necrotic, and some sick pigs will cover the body like armor, and finally gradually peel off from the edges. Severe pigs will eat less or no food, temperature rise and lead to death.

6 Prevention

Pigs should avoid overcrowding, prevent mutual fighting, avoid skin and mucous membrane damage, and deal with trauma in time; when introducing piglets, attention should be paid to whether necrotic bacilli have occurred in the local area; keep the house, environment and utensils clean and dry; correct feed mix and scientific feeding; clean up the feces and dirt on the site in time. When the pig herd disease, should pay attention to inspection, isolation, timely treatment of sick animals; contaminated sites timely disinfection. The treatment of this disease is mainly to improve the feeding and sanitary conditions, eliminate the causes of disease, and cooperate with drug therapy to stop the epidemic and improve the cure rate.

7 Pay attention to the identification of scabies

Swine scabies mite disease occurs more frequently within 5 months of age, starting from the head, and then in the ears and eyes; due to itching and bleeding, scab, hair loss serious, white epidermis and deep cracks; take sick material, find the worm body can be diagnosed, it is a parasitic disease.

Due to the correct diagnosis and timely treatment, the disease was quickly controlled and no pigs died. Here is a reminder to colleagues, do not think that the old disease that has not occurred for more than ten years will not happen again. We should always be vigilant against old diseases and new ones. Blue ear disease, which spread throughout the country last year, has given us a shot. As veterinary workers, we should remember our responsibilities.