Leptospirosis is a complex zoonotic infectious disease and a natural epidemic. It is now occurring in the clinic, but because the majority of farmers usually do not know enough, the defense is negligent, and the prevention and treatment measures cannot be taken in a timely and effective manner after the onset, resulting in economic losses. The disease mainly occurs in pigs, cattle and other animals in the herd. The manifestations are diverse, mainly fever, jaundice, hemoglobinuria, hemorrhagic quality, abortion, skin and mucosal necrosis, edema, etc.

Pigs of all ages can be infected, but the incidence of piglets is more serious, especially in suckling piglets and weaned piglets. The disease is not seasonal, but the summer and autumn rainy season is the peak of the disease, and the infected pigs can be poisoned for a long time. The main source of infection of this disease. The disease mainly passes through the skin, followed by the mucosal spread of the digestive tract, respiratory tract and reproductive tract. Moreover, the disease can infect people, and there is a complex cross-distribution between humans and animals.

Clinical symptoms

In clinical practice, leptospirosis can be divided into acute, subacute and chronic forms.

1. Acute type is more common in piglets, especially suckling pigs and nursery pigs, which are outbreaks or sporadic. The incubation period is 1 to 2 weeks. Symptoms of clinical diagnosis are sudden onset, body temperature rises to 40 ~ 41 ° C, and stays for 3 to 5 days, sick pigs are depressed, anorexia, diarrhea, dry skin, body skin and mucous membrane jaundice, hind limbs with neuropathic weakness, tremor; The case of hemoglobinuria, the color of urine is like strong tea; the stool is green, with a foul smell, and the blood is fecal. The mortality rate can reach more than 50%.

2. Subacute and chronic forms are primarily characterized by damage to the reproductive system. The body temperature of the disease increased to varying degrees, the conjunctiva was flushed, edema, some yellowed, and some jaw, head, neck and body edema. Sows generally have no obvious clinical symptoms, and sometimes they can express heat and no milk. However, sows less than 4 to 5 weeks pregnant may have miscarriage and stillbirth 4 to 7 days after infection with Leptospira, and the abortion rate can reach 20% to 70%. In the late pregnancy, the sow can produce weak babies after infection. The piglets cannot stand, do not suck, and die within 1 to 2 days.

Pathological changes

1. Acute This type is characterized by sepsis, systemic jaundice, and extensive bleeding and necrosis of various organs and tissues. Tissue yellowing and varying degrees of bleeding in the skin, subcutaneous tissue, serosa and visible mucosa, liver, kidney and bladder. Dry skin and necrosis. There is a turbid yellow effusion in the chest and pericardium. Spleen enlargement, congestion, and sometimes hemorrhagic infarction. The liver is swollen, showing a yellowish or brownish color, brittle, gallbladder filling, congestion, and bleeding under the capsule. Kidney enlargement, congestion, and bleeding. Pulmonary congestion, edema, and bleeding spots on the surface. The bladder has red or dark yellow urine. Intestinal and mesenteric congestion, mesenteric lymph nodes, inguinal lymph nodes, submandibular lymph nodes, grayish white.

2. Subacute and chronic manifestations of edema in various parts of the body, most prominent in the head and neck, abdomen, chest wall, limbs. Kidney, lung, liver, and epicardial hemorrhage were obvious. Excess yellow liquid and fibrin are often seen in the serosal cavity. The liver, spleen, and kidneys are swollen. Chronic cases of adult pigs are most pronounced in kidney disease. Sometimes hemorrhagic symptoms can be seen. The disease needs to pay attention to the differential diagnosis of erythrocyte disease and hemolytic anemia in piglets.

If the diagnosis cannot be confirmed according to epidemiology, clinical symptoms and pathological changes, blood, urine and milk can be taken to the diagnostic room of the Pig Service Center of Jiuding Technology Co., Ltd. for testing.

Control measures

(1) Prevention

1. Eliminate all kinds of animals with bacteria and bacteria, including isolation and treatment of sick pigs, elimination of rodents, disinfection and cleaning of contaminated water, sewage, silt, pasture, feed, field and utensils, etc. 2% caustic soda solution or 20% lime milk, bleached powder can be used as a polluted water source.

2. Add 1-1.5 kg / ton of oxytetracycline to the full price

(B) treatment for the treatment of infected pigs: intramuscular injection of procaine penicillin (procukain penicillin 300,000 U, penicillin sodium / potassium 100,000 U) plus dexamethasone injection, one dose per kg of body weight 2-3 million Unit, once a day for 2-3 days. Boars and sows can be given intravenous drip. Glucose + VC supplements body fluids. If you have allergies, you can urgently inject adrenaline. Streptomycin, tetracycline, and doxycycline also have a certain effect.