analysis and treatment of swine toxoplasmosis 1 Introduction Toxoplasmosis is also known as toxoplasmosis or toxoplasmosis, Toxoplasma gondii infection is caused by animal and human zoonotic protozoosis. the disease to high fever, respiratory and neurological symptoms, animals, animal deaths and pregnancy abortion, stillbirth, fetal malformations as the main feature.
disease pathogen is bow insects, carved in the entire development process 5 types, namely, trophozoites (tachyzoites), cysts, schizont, gametocyte and oocyst. gondii development process requires two hosts, which is the trophozoites and cysts intermediate host (humans, pigs, dogs, cats, etc.) formed in vivo, schizont, gametocyte and oocyst in the final host (cat) in vivo formation.
final host is the cat among both host. parasite in cat intestinal epithelial cells, the fission reproduction, reproductive fission repeated several times, the formation of a large number of merozoites, the last merozoites re-enter the epithelial cells, through the reproductive gametes, and finally the formation of oocysts. oocysts excreted with the feces, in the outside world the right temperature, humidity and oxygen conditions, after development of the infectious sporulated oocysts.
discharged from the final host of the oocysts can survive in the outside world 100 days to 1 year and a half, no effect on the general disinfectant. tachyzoite resistance to the weak, the loss of a few hours in saline appeal, a variety of disinfectant can be quickly killed.
3 treatment mechanism
Toxoplasma gondii can infect almost all types of cells. toxoplasma from invading the body parts into the blood and quickly spread into monocytes – macrophages and host tissue cells of various organs or the breeding until the cells burst, can also escape tachyzoites invade neighboring cells, so repeated incessantly, causing local tissue necrosis and focal inflammation of surrounding tissue, this is the acute phase of the basic disease. such as immune function in patients normal, which can quickly generate specific immune clearance of Toxoplasma gondii, the formation of latent infection; parasite can form cysts in the body, long-term potential; once the body immune function, encapsulated in slow tachyzoites escape the broken capsule, causing recurrent . If the patient immunocompromised, is the large population of insects, causing damage to the body disseminated. gondii can be used as antigen, causing allergic reactions, the formation of teeth in the meat to inflammation. In addition, focal damage caused by Toxoplasma gondii, can still cause serious secondary disease, such as small thrombosis, local tissue infarction, hemorrhage and inflammatory cells around the wrapping, for a long time to form the cavity or the occurrence of calcification.
Toxoplasma gondii can affect all kinds of dirty , or organization, predilection sites of lesions in the central nervous system, eyes, lymph nodes, heart, lung, liver and muscle.
4.1 source of infection
cat is the most important source of infection, especially with cat feces discharged oocysts contaminated feed and drinking water are a major source of infection. Putian, Fujian, a pig farm in 1980, because cats rodents and outbreaks of swine toxoplasmosis.
pigs were mainly eating parasite oocysts or meat of animals, organs, secretions and other beverages and drinking water contaminated by digestive tract infection. tachyzoites may also be through the mouth, nose, throat, respiratory mucosa and damaged skin and into the pigs. sows also infect the fetus through the placenta, the phenomenon is widespread.
disease prevalent in the age of 3 months or more varieties of pigs, some acute death, the individual in the 5 ~ 6 days after the onset of failure and died..
the disease-free significant seasonal. in some places in the hot summer month of the season 6-9 multiple.
General pigs after acute infection after 3-7 days of incubation, showing very similar symptoms and classical swine fever, body temperature rises to 40.5-42 ?, missed 7-10 days, pigs depression, decreased appetite, never to waste, hi water, accompanied by constipation or diarrhea. breathing difficulties, often has dogs sitting breathing or abdominal breathing. hindlimb weakness, shaking walking, hi lying. nose dry, coarse hair disorder, conjunctival flushing. as the disease develops, the ears, nose, inside of hind legs stock and lower abdominal skin between purple spots or bleeding. ill post serious difficulty breathing, shaking or rear downer, duration of 10-15 days.
resistant acute pigs had normally after 2 weeks of recovery, but are often left with coughing, breathing difficulties and paralysis of the hindquarters, torticollis, epilepsy-like seizures and other neurological symptoms.
piglets to neurological symptoms, such as circling, ataxia, and so on. 5.3 Pigs
fattening pigs and gilts showed a large can or tar-like Campylobacter was no blood in the diarrhea.
pregnant sows if acute toxoplasmosis, high fever, do not eat, mental Weidun and lethargy, this can produce symptoms for several days after the stillbirth or miscarriage, even if the output will be alive acute death or hypoplasia, not eating or freaks. sows often heal quickly after giving birth.
6 pathological changes
visceral most characteristic lesions of the lung , lymph nodes and liver, followed by spleen, kidney, intestine. lung was lobar pneumonia, dark red, interstitial widening, and expansion into the slurry containing large amounts of lung airless, cut out large amounts of slurry with foam. the body size of lymph nodes ranging from bleeding and necrosis of gray points, especially inguinal and mesenteric lymph nodes the most significant. liver swelling and a diffuse large tip to the soybean necrotic gray or sallow. spleen early in the disease a significant swelling, a small amount of bleeding point, the late decline. kidney section with the tip surface and bleeding points. mucosal hypertrophy, erosion, bleeding from the jejunum to the colon spots. pericardium, chest and abdominal cavity with water. histopathological changes to, focal liver necrosis, congestion, systemic lymph node congestion, hemorrhage, non-suppurative encephalitis, pulmonary edema and interstitial pneumonia, necrosis in the liver cytoplasm of liver cells surrounding the alveolar epithelial cells and mononuclear cells, lymph node sinus endothelial cells common are single and in pairs or gondii ranging from 3,5 orders, the shape is round, oval, arched or crescent shapes, etc..
no specific clinical symptoms of the disease, pathological change should be based on pathology, and pathogenic and serological examination to make diagnosis.
7.1 pathological change
visual body mucosa, ears, belly and legs inside of the skin flake purple patch. systemic lymph node high degree of congestion and edema. thorax, abdomen large effusion. lung dark red, shiny, cut out red and yellow foamy liquid, between the quality of thickening, bleeding points and gray necrosis. liver, spleen and kidney necrosis sallow sizes, kidneys were khaki. heart soft texture, significant expansion of the right ventricle. fundic gland area mucosa flushing, bleeding . mucosal bleeding point.
? direct microscopic examination: take lymph nodes, blood, brain, liver, spleen, lung, kidney and muscle smears, stained examination whether Toxoplasma gondii. ? animal experiment: the organization of the various organs of normal saline was injected into mice intraperitoneally emulsion. If mice morbidity or mortality, ascites can be used syringe, made of pressed, using high magnification Check for speed crack body.
7.3 Serological tests
staining reaction used to free toxoplasmosis (speed split body), respectively, in normal and immune serum by a -2 hours later, remove the addition and subtraction of the blue. after making the Toxoplasma antibody stained not color, check out the Huanchu Toxoplasma gondii antibodies in serum exists in animals 2 weeks after onset can have this reaction, this method is used in early diagnosis.
8 swine disease control
selected sulfonamide must be chosen with “trimethoprim” (TMP) of sulfa drugs. where the sulfa drugs preceded by a “synergistic” or “compound” should have added a representative of TMP. sulfadiazine sodium, such as efficiency, efficiency sulfa -5– pyrimidine trimethoprim, sulfamethoxazole trimethoprim hydrochloride efficiency, cotrimoxazole and other one either.
? sulfa -6– methoxy-pyrimidine (SMM), per kilogram of body weight per day 60mg, dubbed the solution for intramuscular injection of 10%, with 3-5 days. ? sulfadiazine (SD) plus pyrimethamine, the former per kilogram of body weight 70mg, which per kilogram of body weight 6mg, 2 times a day medication, the amount of the first times, even serving for 3-5 days. ? amine phenylsulfonyl (SDDS), 15mg per kg body weight drug. ? sulfamethoxazole (SMZ), per kilogram of 100mg, 1 time a day medication, and even served 2-3 days. ? efficiency sulfa -5– methoxy pyrimidine (containing 10% sulfa -5– methoxy pyrimidine and 2% three Trimethoprim), per kilogram of body weight does not exceed the amount of 2ml intramuscular injection, day 1, even the injection for 3-5 days. ? acetylspiramycin per kg body weight 5mg, 2 times a day service, the first times the amount, and even clothes 2-3 days.
for toxoplasmosis, only sulfa drug effects, other antibiotics ineffective, and the use of the medication must adhere to strict principles: first, the dose should be sufficient, the first dose should be doubled; secondly, according to sulfa drugs in the body to maintain the time, strict compliance with therapy; the third, stopping too early, treatment of the disease a course of treatment takes 5 to 7 days, usually to 5 days, pig temperature drops, there appetite, but this time not stopping, we must continue medication 1 to 2 days, or easy to relapse, and relapse after treatment is extremely difficult. Fourth , ill pigs sulfa 6 – methoxy-pyrimidine intravenous injection, efficacy fast, and can quickly control outbreaks of disease development, the amount of 0.5 ml / kg; to be in remission, may reduce the number of drugs, or changed to oral therapy. muscle large injection of drugs, be sure to use multi-point, deep intramuscular injection, is conducive to drug absorption.
in pig farms and the surrounding technology support should be banned cat, the breeder should also avoid contact with cats.
barn to keep clean, regular disinfection of the sows aborted fetuses, feces and dead bodies should be strictly treated to prevent pollution of the environment.
in disease-prone season, were added per ton of feed, 500 grams of sulfadiazine and pyrimethamine 25 grams, and even fed one week, can effectively prevent the occurrence of toxoplasmosis.
From the article – the piglets Network