Diagnosis and prevention of porcine dysentery

Pig dysentery is also called blood dysentery. It is a serious intestinal infectious disease caused by Borrelia pullorum. The main clinical symptoms are severe mucinous hemorrhagic dysentery, acute hemorrhagic dysentery, subacute and chronic mucinous diarrhea. The pathological features of autopsy were catarrhal, hemorrhagic and necrotizing inflammation of large intestinal mucosa.

Main points of diagnosis

The main results are as follows: 1. Under natural circumstances, only pigs can be infected, and pigs of all ages and breeds can be infected, but the main damage is piglets of 2-3 months old; the morbidity and mortality of piglets are higher than those of big pigs; sick pigs and carriers are the main sources of infection, and the occurrence of the disease is not obvious seasonality; due to the existence of infected pigs, the disease is often dispersed through the transfer and sale of pigs. Pigs with bacteria often do not get sick under normal feeding and management conditions. when there are adverse factors to reduce pig body resistance, insufficient feeding, lack of vitamins and stress factors, it can promote the occurrence of disease.

2. The most common clinical symptom is diarrhea with different degrees. Generally pull soft dung first, gradually change to yellow dilute dung, mixed with mucus or with blood. When the condition is serious, the defecation is red paste, there are a lot of mucus, bleeding mass and purulent secretion. Some pull gray, brown or even green paste dung, sometimes with many small bubbles, and mixed with mucus and fiber pseudomembrane. Diseased pigs are lethargic, anorexic and like drinking water, arch back, dehydration, abdominal curling, walking and rocking, kicking with hindlimbs, rough coat, rapid weight loss, and defecation incontinence in the later stage. Around the anus and the tail root are contaminated by feces, stand up powerless, extremely weak and die. The body temperature of most diseased pigs is normal. Chronic illness, mild symptoms, feces containing more mucus and necrotic tissue fragments, longer disease period, progressive emaciation, growth stagnation.

3. Pathological examination showed that the main pathological changes were limited to large intestine (colon, cecum). Acute swine is mucous and hemorrhagic inflammation of large intestine, mucosal swelling, congestion and bleeding, intestinal cavity full of mucus and blood; longer cases, mainly necrotizing colitis, mucous, flaky or diffuse necrosis on the mucosa, necrosis is often limited to the mucosal surface, the intestine is mixed with a large amount of mucus and necrotic tissue fragments. There are often no obvious changes in other organs.

4. Etiological diagnosis (1) fresh feces or large intestinal mucosal smears of diseased pigs were stained with Giemsa, ammonium oxalate crystal violet or complex red solution, and microscopic examination showed that more than 3 large spirochetes with 3-4 curved spirochetes could be seen in each visual field at high magnification. (2) isolation and culture; need to be carried out under anaerobic conditions.

5. Serological diagnosis includes agglutination test, immunofluorescence test, indirect hemagglutination test, enzyme-linked immunosorbent assay and so on. Agglutination test and enzyme-linked immunosorbent assay are better, which can be used as an index for judging grafting.

Prevention and cure method

1. Prevent the purchase of infected breeding pigs from the hospital; if introduced, pigs should be isolated, observed and quarantined.

2, timely treatment of diseased pigs, drug treatment, often have a certain effect, such as MAQO,3- methyl-acetyl-quinoxalin-1 Magin 4-dioxide) 5mg/kg, orally, twice a day for 3 days as a course of treatment, or according to 0.5% dysentery net solution 0.5ml/kg, intramuscular injection Many kinds of antimicrobials such as dimethylnitromidine, neomycin sulfate, dysentery, lincomycin, tetracycline antibiotics and so on have certain curative effect. It should be pointed out that the disease is easy to relapse after treatment, and good results can only be achieved by adhering to the course of treatment and improving feeding and management.

3. Do a good job in the cleaning and disinfection of piggery and environment, and deal with feces.

4. Sick pigs had better be eliminated.

5. Better purification effect can be obtained by adhering to the purification measures of the combination of medicine, management and hygiene.