What are the common diseases in pig factories?

(1) Overview

Swine asthma, also known as pig asthma, mycoplasma hyopneumoniae or mycoplasma hyopneumoniae, is called endemic pneumonia abroad.

The pathogen is mycoplasma hyopneumoniae, which was once translated as mycoplasma. Pathogens mainly exist in respiratory tract, lung and hilar lymph nodes of pigs.

Swine asthma is a chronic respiratory infectious disease, characterized by cough and wheezing, with high incidence and low mortality, which affects the growth and development of pigs, is easy to be infected with many diseases and brings huge losses to pig production.

There is no age, variety, sex and seasonality in the onset. The morbidity and mortality of suckling piglets and young pigs are higher, followed by late pregnancy and lactating sows.

Cold, damp, rainy, improper feeding management and poor sanitary conditions can all induce or aggravate this disease. The infected pigs have been infected for a long time after rehabilitation, and some of them are as long as 1 year.

(2) Clinical symptoms

Intermittent cough and wheezing, runny nose, visible mucosal cyanosis; There was no obvious change in appetite and growth was hindered.

The temperature is generally normal. If a secondary infection occurs, the body temperature will rise and the condition will be more complicated.

(3) Pathology

Pulmonary lesions are obvious, such as swelling, pneumothorax and pneumothorax; There are fused bronchopneumonia lesions in the anterior lower margin of each lobe of the lung, and the boundary is obvious.

From "pork-like degeneration" to "pancreatic degeneration" or "shrimp-like degeneration" (the initial lesion is red-gray and the section is as thin as honey, commonly known as pork-like degeneration of the lung, and later it is lavender, crimson and grayish yellow with enhanced toughness, commonly known as "pancreatic degeneration").

Pericarditis, pleurisy and pulmonary pleural adhesion can be seen after secondary infection.

(4) Prevention and control

Zhiyuan Jing 100mg/kg or doxycycline 150mg/kg or clozapine 250mg/kg or colistin sulfate 40mg/kg (two weeks before and after weaning); Kanamycin and oxytetracycline are also sensitive.

Immunization: inactivated pig asthma vaccine, piglets 1~5 days old, 0.25ml/ head; Two exemptions for 3~4 months old; Breeding male sows twice a year, 5ml/ time.

Second, contact with contagious pleuropneumonia.

(1) Overview

Also known as Haemophilus parahaemolyticus disease in pigs, the pathogens are Haemophilus parahaemolyticus and Haemophilus parahaemolyticus.

Acinetobacter pleuropneumoniae is a strict mucosal parasite, which usually mainly exists in the respiratory tract of pigs. At present, serotype 12 has been found in this strain, and 7 confidants are mainly prevalent in China.

This is a contact respiratory infection. Characterized by acute hemorrhagic pleuropneumonia and chronic fibronecrotizing pleuropneumonia, it is internationally recognized as one of the most harmful infectious diseases to the pig industry.

The mortality rate of acute pigs is high, generally around 50%, and chronic diseases are often tolerated.

Regardless of breed, age, sex and season, piglets about 3 months old (6 weeks to 6 months old) are most susceptible, and they are most susceptible in April, May and September, 10 month.

The inducement is pressure or deterioration such as traffic, sudden change of climate, poor ventilation, congestion and sudden change of environment.

(2) Clinical symptoms

High fever, above 4 1.5℃; Cough, mouth breathing, late dyspnea, sitting on a dog; Sometimes reddish foamy secretions can be seen in the nose and mouth; Nose, ears, legs and side skin are purple; There was foam-like blood secretion in the mouth and nasal cavity before death; Individual pigs vomited, and a few pigs were accompanied by diarrhea; Some joints are swollen; Crappy.

(3) Pathology

Trachea and bronchus are filled with bloody foam-like secretions; There is reddish exudate in the chest cavity.

Pneumonia, interstitial lung filled with bloody colloidal fluid, obvious fibrous pleurisy sometimes manifests as adhesion between lung and pleura (congestion and edema). At the early stage of pneumonia, there was cellulose attachment and yellow exudate exudation. In the later stage, the lung consolidation area is large, and there is connective tissue-like adhesion on the surface. Later, the focus of pneumonia hardened or became necrotic.

Sometimes exudative cellulose pericarditis can be seen.

(4) Prevention and control

Ampicillin: 4~ 15mg/kg body weight, intramuscular injection, twice a day for 3 days;

Kana: 10~20mg/kg body weight, intramuscular injection twice a day for 3~5 days;

Sulfonamides: 0.07~0. 1mg/kg body weight, intramuscular injection, twice a day for 3 days;

Compound sulfamethoxazole: 0.07~0. 1mg/kg body weight, intramuscular injection, twice a day;

Methylsulfone: 0. 1ml/kg body weight, intramuscular injection, twice a day;

Zhiyuan. com: 100~ 150mg/kg mixture.

(A few pigs with severe symptoms were injected, and a large group were injected with mixed materials)

Immunization: Inactivated vaccine of porcine contagious pleuropneumonia oil adjuvant, inject 2ml into sow and 2ml into boar twice a year before 1 month; Piglets were injected with 0.5~ 1.0ml at the age of 4~5 weeks, and strengthened every 7~ 14 days/time.

Three. Swine Infectious Atrophic Rhinitis

(1) Overview

The main pathogen of this disease is Bordetella bronchiseptica, followed by Pasteurella multocida type D, which produces toxins.

Other pathogenic microorganisms such as Pseudomonas aeruginosa, defensible bacteria, Haemophilus, Corynebacterium pyogenes, Mycoplasma hyopneumoniae, Trichomonas and porcine cytomegalovirus are also related to infection.

The disease is a chronic respiratory infection in pigs, characterized by rhinitis symptoms such as sneezing and nasal congestion and facial changes, which mainly leads to delayed growth and development of pigs, low feed reward and prolonged slaughter period.

Pigs of all ages and breeds can be infected without seasonality.

It is common that infected sows with no clinical symptoms detoxify from the respiratory tract to infect piglets, and then the piglets expand the infection.

The disease spreads slowly and sporadically. In addition, the disease can also infect dogs, cats, cows, horses, sheep, chickens, rabbits and people, causing chronic rhinitis and purulent bronchopneumonia.

(2) Clinical symptoms

Rhinitis, sneezing and poor breathing; Thick, purulent, bloody nose; Tears, "half moon" tears.

Nasal and facial deformation; Twisted, shortened or upturned.

(Facial deformities mostly occur in piglets. The symptoms of 30~40Kg pigs are mild or asymptomatic, and most large pigs are asymptomatic carriers. )

(3) Pathology

Lack of ocular lesions

(4) Prevention and control

Penicillin, streptomycin, sulfonamides, amoxicillin, quinolones and ceftiofur are sensitive.

Immunization: Generally, erysipelas pneumonia combined vaccine is selected, 60-day-old piglets 1 time; One month before the breeding of reserve pigs 1 time; Breeding boars twice a year. Inoculate according to the instructions.

Six, streptococcosis

(1) Overview

Streptococcus suis is the general name of various infectious diseases in pigs caused by several main streptococci (groups C, D, E and L).

It is characterized by acute type, often showing hemorrhagic septicemia and encephalitis; Chronic type is characterized by arthritis, endocarditis, suppuration of lymph nodes and tissue. People and animals suffer from * *.

Only pigs are susceptible, not seasonal. Pigs of all ages and breeds are susceptible. The morbidity and mortality of newborn piglets and suckling piglets are the highest, followed by medium-sized pigs and pregnant sows, and the morbidity of adult pigs is less.

Mainly through digestive tract infection, but also through respiratory tract infection.

(2) Clinical symptoms

Septic blood type: sudden onset, high fever, lethargy, depression and shortness of breath; Serous, mucinous nasal discharge, constipation or diarrhea, bloody stool, yellow urine or hematuria; Conjunctiva is flushed, congested and tearful, and the skin at the centrifugal end is purple; * * * Ataxia, molar, empty chewing.

Meningitis type: more common in suckling piglets, with high body temperature and constipation; * * * dysfunction, turning around, corner workers stretching backwards, twitching, unable to lie down, paddling on all fours, foaming at the mouth; Finally, he died of exhaustion or paralysis, with a high mortality rate.

Lymph node abscess type: it is more common in inflammation and swelling of submandibular, pharyngeal, subauricular and cervical lymph nodes, unilateral or bilateral. Inflammatory lymph nodes can mature and fester, burst and discharge pus, and then the whole body symptoms get better, forming scar healing.

Arthritis type: mainly swelling and limping of limbs, or worsening or improving.

(3) Pathology

Hemorrhagic serosa and mucositis; Congestion of nose, trachea and lungs, hepatosplenomegaly and hemorrhage.

Enlargement or necrosis of lymph nodes in the whole body; Joint jelly or cellulitis; Encephalitis, cerebral parenchymal hemorrhage.

(4) Prevention and control

Penicillins are the first choice, and muscle attention is given once a day for 3 days; Followed by 20% sulfadiazine sodium, 0. 1 g /kg body weight, intramuscular injection, twice a day for 2 days. Local joint surgery is feasible.

Immunization: all weaned or adult pigs are injected with 1m 1 subcutaneously (according to the bottle label), or piglets are exempted for the first time at the age of 20-30 days and for the second time at the age of 50-60 days; Sows are vaccinated 3 weeks before delivery (according to regulations).

Seven, piglet paratyphoid.

(1) Overview

Also known as Salmonella suis, it is an infectious disease of piglets caused by Salmonella.

It is characterized by acute septicemia and extremely high mortality. Chronic diffuse cellulose necrotizing enteritis occurred in the large intestine, which showed intractable diarrhea and seriously affected the growth and development of pigs. The disease is a bacterial infectious disease that threatens piglets. Many types of salmonella are pathogenic to humans and many kinds of domestic animals and poultry.

Pigs of all ages can be infected, and piglets aged 1~4 months are the most susceptible to infection.

No seasonality, more common in rainy and humid seasons.

Incentives can promote the occurrence of this disease, especially when classical swine fever occurs, it is often secondary or complicated with this disease infection.

The disease is mainly infected through the digestive tract, but also through mating.

(2) Clinical symptoms

More common in weaned piglets; High fever, lethargy and dyspnea; The skin at the centrifugal end is crimson or purplish red.

Refractory diarrhea, gray-white, yellow-green, foul-smelling feces; Hanging his stomach, hunching his back and screaming, his hair is rough.

(3) Pathology

Systemic serosa, mucous membrane and visceral hemorrhage.

Lymph node enlargement, systemic bleeding.

Thickening of blind wall, nodular wall and ileum wall (wheat bran pseudomembrane).

Liver, spleen and kidney are enlarged, and the gray-yellow necrosis focus is the size of liver tip or millet.

(4) Prevention and control

Thiamphenicol, Keliwang, Neomycin, Quinolones, or (Qingda+Kana+Lijun Jing), etc.

Immunization: Vaccinate with piglet paratyphoid attenuated vaccine 1 time from 28 to 30 days old.

Inoculation method:

1, oral: diluted with cold boiled water 1~ 10ml/ serving, 4 serving/tablet, oral.

2. Mixing: dilute 5~ 10ml/ head with cold boiled water, 4 heads/tablet, and mix.

3. intramuscular injection: intramuscular injection behind the ear 1ml.

Eight, piglet yellow dysentery

(1) Overview

Also known as colibacillosis of newborn piglets, it is an acute and highly fatal infectious disease caused by pathogenic Escherichia coli. It is characterized by severe diarrhea, yellow or yellow-white feces, and rapid dehydration.

The antigens of Escherichia coli are complex, including O, H and K; There are thousands of serotypes; The resistance to external environment is not strong.

The pathogenicity of Escherichia coli depends on its ability to adhere, colonize and proliferate in the small intestine and its ability to produce toxins. Adhesion factors or cilia determine the ability of bacteria to colonize. Once the bacteria are colonized, diarrhea will be caused by the production of toxins. The most important adhesion factors are F4(K88ab, K88ac), F5(K99) and F6(987P).

Early onset, mainly affecting 1~3-day-old piglets, acute onset, obvious symptoms and high mortality.

There is no seasonality, but the incidence rate is higher when it is cold, when the delivery room is humid and the sanitary conditions are not good. Once a pig farm is sick, it is difficult to eradicate it.

It is mainly digestive tract infection, and sow with bacteria is the main infectious disease.

(2) Clinical symptoms

The water sample is thin feces, yellow or grayish yellow, containing small pieces of curd and small bubbles.

Sick pigs are thirsty, lack of milk, dehydration, emaciation, coma and exhaustion.

(3) Pathology

Intestinal mucosa congestion, edema, and even shedding.

The intestinal wall is thin, loose and swollen, especially the duodenum. Intestinal contents are yellow, sometimes mixed with blood.

The heart, liver and kidney are degenerated, and in severe cases, there are bleeding spots or coagulation necrosis.

(4) Prevention

Do a good job in prenatal and postpartum management of sows; Strengthen the nursing of newborn piglets.

Drug prevention (oral sensitive antibiotics within 0/2 hours after birth).

Microbial preventive agents (such as promoting bacterial growth, regulating bacterial growth, milk Kang Sheng, Kangdabao, etc.). ) can inhibit Escherichia coli by regulating the balance of intestinal flora in piglets.

(5) treatment

Comprehensive measures such as antibacterial, antidiarrheal, digestive aid and rehydration should be taken to treat yellow and white dysentery of piglets.

Antibacterials: Apramycin, Streptomycin, Ciprofloxacin, Enrofloxacin, Thiamphenicol, Amoxicillin, Xieliting and Keliwang.

Antidiarrhea: tannin.

Help digestion and absorption: feed mom, baking soda, pepsin, etc.

Liquid supplement: oral glucose saline and multivitamins. Formula of glucose physiological saline: Add 20g of glucose, 3.5g of sodium chloride, 65,438+0.5g of potassium chloride and 2.5g of sodium bicarbonate into 65,438+0,000ml of water.

Immunization: pregnant sows were immunized 30 days before delivery and 15 days, and the vaccine was genetically engineered Escherichia coli.

Nine, piglet dysentery

(1) Overview

Also known as delayed Escherichia coli, it is a common diarrhea in piglets during lactation.

It is characterized by milky white or grayish white stench, sparse feces, high morbidity and low mortality, but the growth rate of piglets is obviously slowed down.

The cause is complicated, and it can't be completely determined. It is generally believed that the imbalance of intestinal flora in pigs and the overproduction of Escherichia coli are the important causes of the disease. It has been proved that porcine rotavirus is one of the pathogens of pullorum disease in piglets.

The disease mostly occurs in piglets aged 10~30 days, and rarely occurs in piglets less than 7 days and more than 30 days. No seasonality, severe climate change in winter and spring, rainy, humid or poor warmth retention, and insufficient milk for sows is more common.

The incidence is closely related to feeding management and pig house hygiene, and stress and other factors are also one of the important pathogens.

Mainly through digestive tract infection.

(2) Clinical symptoms

Piglets suddenly have diarrhea, and the same litter appears one after another, discharging white, grayish white, fishy, pasty or pulpy feces.

Piglets are listless, chills, dehydrated, eat little or no milk, and sometimes spit milk.

Generally, sick pigs are mild and can be cured by timely treatment, but most of them become stiff pigs due to repeated attacks. Severe cases of fecal incontinence, 1 week or so died.

(3) Pathology

The dead pig was dehydrated, emaciated and pale.

The gastric mucosa is congested and edematous, and the intestinal contents are gray, sour or mixed with bubbles.

Intestinal wall is thin and translucent, mucous membrane is congested, bleeding is easy to peel off, mesenteric lymph nodes are swollen, and secondary pneumonia is often found.

(4) Prevention and control

It is basically the same as the prevention and control measures of yellow dysentery in piglets.

Edema disease

(1) Overview

Enterotoxemia of weaned piglets caused by pathogenic Escherichia coli: it is characterized by edema of stomach wall and other parts.

Often sudden onset, the incidence rate is low, but the mortality rate is high, endotoxic shock symptoms often appear, and death is fast.

This pathogen often has no adsorption factor, but hemolysis, which has both toxins and neurotoxins.

(2) Clinical symptoms]

Eyelid, head, neck and even whole body edema.

Generally, there is no change in body temperature, rapid breathing and heartbeat, muscle tremor, blindness, rotation, * * * ataxia, convulsions or convulsions, screaming, foaming at the mouth, convulsions on the ground, paddling on the limbs, and finally paralysis of the limbs, inability to stand, shock and death.

(3) Pathology

Gelatinous edema of upper and lower eyelids, face, mandible, etc.

Mucosal edema of gastric mucosa (between gastric curvature and stomata, mucosa and muscle layer).

There is bloody effusion in pericardium and body cavity.

Almost all lymph nodes in the body have edema, especially mesenteric lymph nodes (colon and mesentery).

(4) treatment

Edema buster or Edema Kang (5ml/ head), twice a day, 1~2 days, sodium selenite VE injection, 1~2ml intramuscular injection, twice, furosemide diuresis. Add 1 ml to 20% sulfamethoxazole sodium, 1 ml to 50% sulfamethoxazole sodium, and 3 ml/kg body weight to 50% glucose for intravenous injection twice a day.

Eleven, piglet red dysentery

(1) Overview

Also known as porcine infectious necrotizing enteritis or clostridial enteritis. It is a highly lethal enterotoxemia in piglets.

The pathogen is Clostridium perfringens type C, which can produce α and β toxins, causing enterotoxemia and necrotizing enteritis in piglets. It is characterized by bloody stool (bloody dysentery), intestinal necrosis, acute onset, short course of disease and high mortality in piglets aged 1 ~ 3 days.

Susceptible animals range widely: pigs, horses, cows, chickens, rabbits, deer and so on. Among them, ruminants, especially sheep, are more susceptible to infection, and so are people. Pigs mostly occur at the age of 1-3 days, and rarely get sick above 1 week.

There is no seasonality, and the infection is mainly transmitted through the digestive tract.

Once the disease occurs, the pathogen will exist for a long time, and the spores of this bacteria widely exist in human and animal intestines, polluted external environment, sewers and other places for a long time.

(2) Clinical symptoms

The disease is acute, and the piglets can get sick within 1 day after birth, and the reddish and reddish-brown feces are discharged.

Sick pigs are rapidly dehydrated, emaciated and tired, and some sick pigs vomit, scream and act involuntarily.

Most of them died within a few days. If the course of disease exceeds 7 days, intermittent or persistent diarrhea will occur, and the sick pigs will stagnate, gradually lose weight, fail or die.

(3) Pathology

There is a lot of scarlet effusion in the abdominal cavity.

The jejunum is dark red, and the intestinal cavity is full of bloody liquid, and the contents are reddish brown with small bubbles.

Intestinal submucosa, muscle layer and mesentery contain bubbles.

A necrotic yellow pseudomembrane is formed on the intestinal wall with a long course of disease, which is generally not easy to fall off, and the mesenteric lymph nodes are swollen and bleeding.

(4) Prevention and control

Piglets were injected with porcine red dysentery serum after birth, 3 ml/kg body weight; Oral "life-saving oil" after birth, or oral gentamicin; Antibiotics (penicillin, sulfanilamide, etc. ) combined with VC combined therapy.

Immunization: Pregnant sows were immunized with red dysentery vaccine 30 days before delivery and 15 days before delivery.

Twelve, swine dysentery

(1) Overview

Commonly known as swine dysentery, the pathogen is treponema suis dysentery. Characterized by mucus or mucus hemorrhagic diarrhea.

Once the disease is introduced, it is not easy to eliminate it. The carrier rate of recycled pigs is very high, and the carrier time can reach more than 70 days, which seriously affects the production and development of pigs and increases feed consumption.

Only infected pigs, regardless of breed, sex and age, are mostly pigs of 7- 12 weeks old, and there is no obvious seasonality.

The digestive tract is the only route of infection, with flies carrying bacteria for 4 hours, mice carrying bacteria for more than 0/00 days and mice carrying bacteria for 2 days. It is also the source and disseminator that cannot be ignored.

(2) Clinical symptoms

Different degrees of diarrhea, first soft and then thin, and finally watery stool, mixed with mucus or blood. In severe cases, the feces are red and mushy, containing a lot of mucus, blood clots and purulent secretions.

Temperature rise, 40 ~ 4 1℃, listlessness, anorexia, emaciation and dehydration, hunchback of back and abdomen, roughness, incontinence, failure, recovery or death in the later stage.

(3) Pathology

Mainly catarrhal and hemorrhagic enteritis of the large intestine; The mesentery and its lymph nodes are hyperemia and edema.

The intestinal cavity is full of mucus and blood, and the mucosa with a long course of disease forms a yellow and gray cellulose pseudomembrane similar to bran or bean dregs, which is easy to fall off.

(4) Prevention and control

Lijun Jing, tylosin, cyclopropane, etc.

Thirteen. spirochete

(1) Overview

Also known as leptospirosis. The pathogen is pathogenic leptospira, which is a zoonotic disease. It is characterized by fever, jaundice, anemia, hemoglobinuria, abortion, skin mucosal necrosis and edema.

Almost all warm-blooded animals can be infected, among which pigs and cattle are the most susceptible.

It can be infected at any age, especially in piglets. No seasonality, more common in summer and autumn.

The main injury is skin infection, followed by mucosa (digestive tract and respiratory tract mucosa), which is generally sporadic and sometimes endemic.

(2) Clinical symptoms

Piglets have fever (39~40℃), thick stools, hard and granular urine, urine as thick as tea, hematuria (reddish) or hematuria.

There is edema in the neck of the sick pig head, so it is named "swollen head disease" or "big head plague". Conjunctivitis can be seen with yellow staining of mucosa.

Pregnant sows miscarry, while lactating sows have fever and do not produce milk.

(3) Pathology

Head, neck and subcutaneous tissue edema, serosa and mucosa yellow staining.

The bladder is highly inflated and full of reddish brown, similar to the urine of strong tea.

The liver is swollen, yellow-brown, jaundice cyst is full, the kidney is swollen, and there is gray necrosis focus.

The aborted fetus has edema, erythema on the skin and black necrotic focus in the lungs.

(4) Prevention and control

Commonly used are streptomycin, oxytetracycline and chlortetracycline. Combined with symptomatic treatment, intravenous injection of glucose and vitamin C and cardiotonic diuresis are beneficial to improve the cure rate.

Immunization: Leptospira vaccine, 2ml subcutaneous or intramuscular inoculation for piglets below 15kg, 3~5ml adult pigs, every 7 days 1 time.

Fourteen, brucellosis

(1) Overview

Brucellosis in pigs is an acute or chronic infectious disease caused by Brucella. It is characterized by abortion and infertility of sows and orchitis of boars.

Regardless of age and breed, pregnant sows are most susceptible to infection, and suckling piglets do not show clinical symptoms after infection.

The secretions, excreta, milk and semen of sick animals are generally infected by bacteria, mainly through digestive tract infection, but also through skin, mating and respiratory tract infection.

Not seasonal, sporadic or local.

(2) Clinical symptoms

Pregnant sow abortion, residual afterbirth, breast swelling and viscous purulent secretion oozing from vagina.

Testicular and epididymitis in boars are characterized by obvious swelling of testicles, late atrophy and loss of mating ability.

In a few cases, arthritis, mostly in the hind limb joints, swelling, increased cystic fluid, and sometimes hard joints.

Lymph nodes in submaxillary, neck, groin and pharynx are often swollen.

(3) Pathology

Purulent inflammation and catarrhal inflammation of uterine mucosa in sows.

Purulent or necrotizing orchitis and epididymitis purulent or necrotizing lesions can be seen on testicular sections of boars.

Arthritis, which mostly occurs in the compound joints of limbs, begins with synovitis, followed by suppurative or cellulosic arthritis.

(4) Prevention and control

Regular serological quarantine, timely elimination of positive and suspicious pigs.

Fifteen, pig dermatomycosis

(1) Overview

Porcine dermatomycosis is also called dermatomycosis, superficial mycosis and microsporomycosis. , commonly known as ringworm, alopecia ringworm, alopecia ringworm, etc. It is the general name of pig dermatosis caused by various dermatopathogenic fungi.

Regardless of breed, age or sex.

No seasonality, more common in autumn and winter. Cold, humid and unsanitary environment is more conducive to the occurrence and spread of this disease.

(2) Clinical symptoms

There are patches, congestion, edema, depilation, papules, blisters, nodules, scabs, scales or ulceration on the skin of head, neck and shoulders, and some of them have exudation or suppuration.

The sick pig showed local itching. This disease generally does not cause visceral lesions.

(3) Prevention and control

First cut the affected area, then wash the scab skin with warm soapy water, and apply 10% salicylic acid alcohol or ointment or 5%~ 10% copper sulfate solution every day or every other day until it is cured.

Can also be used externally, such as clotrimazole tinea lotion, nystatin, griseofulvin, etc.

Sixteen, swine fever

(1) Overview

Classical swine fever, commonly known as intestinal plague, classical swine fever in the United States and classical swine fever in Britain, is an acute, febrile and septic infectious disease of pigs.

The pathogen is classical swine fever virus. At present, it is considered that there is only one serotype of classical swine fever virus, but the virulence of the strain is divided into strong, medium and weak.

The characteristics of this disease are: acute septic changes, bleeding and necrosis of parenchymal organs. Subacute and chronic types not only have different degrees of septic changes, but also have cellulosic and necrotizing enteritis. With high morbidity and mortality, it is an important infectious disease in pigs, often infected with paratyphoid fever and Brucella.

This disease only infects pigs under natural conditions.

Regardless of breed, age, sex and season.

Generally transmitted through the digestive tract, but also through respiratory tract, conjunctiva infection, or through damaged skin or placenta infection.

(2) Clinical symptoms

The most acute type: acute onset, high fever, spasm, convulsion, cyanosis of skin and visible mucosa, bleeding point, and rapid death.

Acute type and subacute type: high fever, mental depression, anorexia, initial constipation, diarrhea, hydrocele in boar foreskin, centrifugal bleeding or erythema, with few neurological symptoms and high mortality.

Chronic type: appetite is good and bad, body temperature is high and low, constipation and diarrhea alternate. The skin of the tip of the ear, the root of the tail and the limbs is often purple and necrotic, even dry. Emaciation, general weakness, paralysis of hind limbs, unsteady walking or inability to stand.

Reproductive disorders (sow virus syndrome): early and middle infection, sow abortion, stillbirth, fetal mummy, etc. Infection in the third trimester, normal appearance, life-long infection of piglets, immune tolerance (no immune response).

(3) Pathology

Bladder mucosa and larynx will hate cartilage mucosal bleeding, pale kidneys, bleeding spots, spleen bleeding and marginal infarction.

Lymph nodes are swollen, bleeding and marble-shaped.

Necrotizing enteritis, button swelling or ulcer of cecum. Punctate hemorrhage of left atrial appendage.

Stillborn fetus subcutaneous edema, ascites, subcutaneous, limb bleeding.

(4) Prevention and control

immune

General area: pre-breast immunization, the second immunization around 70 days old, pay attention to the allergic reaction during pre-breast immunization.

On the basis of the above immunization, breeding pigs should be strengthened 1 time every six months, reserve sows should be strengthened 1 time 20-30 days before mating, and sows should be strengthened 1 time about 25 days before mating.

Emergency vaccination: 4~8 times of the constant, and antibodies are produced in 5~7 days.

Treatment: Dexamethasone, Analgin, Virin and Antibiotics.