Detailed Explanation of the Causes and Comprehensive Prevention and Control Measures of Swine High Fever Syndrome
Recently, many @#@227@#@ farms have consulted about the causes and prevention and control technical issues of swine high fever syndrome. Based on my own practical experience, the author puts forward some views for your reference.
Causes
Swine high fever syndrome is essentially a swine disease caused by mixed infection of multiple viruses, bacteria, and protozoa triggered by immunosuppressive swine diseases.
Biological factors: mixed infection of pathogens such as classical swine fever virus, circovirus, porcine reproductive and respiratory syndrome virus, pseudorabies virus, Eperythrozoon, Toxoplasma, Streptococcus, Salmonella paratyphi, Mycoplasma, Actinobacillus pleuropneumoniae, Haemophilus parasuis, and Pasteurella. There can be more than 15 types of pathogens, among which classical swine fever virus has the highest infection rate and is the most typical. Mixed infection of Toxoplasma, Eperythrozoon, porcine reproductive and respiratory syndrome virus, circovirus, and classical swine fever virus is common. There is also mixed infection of classical swine fever virus and Salmonella paratyphi in piglets, often dominated by classical swine fever virus, with mixed infection of one or more than two kinds of viruses, bacteria, and protozoa. Therefore, the mortality rate is high, the cure rate is low, and it may even wipe out the entire herd.
Stress factors: high temperature and high humidity climate, high stocking density, poor weaning transition, mixing groups and fighting, long-distance transport, vaccination, water deprivation causing stress, etc.
Nutritional factors: deficiency and imbalance of vitamins and trace elements in feed, or increased content of growth-promoting and liver-damaging elements; moldy feed, with mycotoxins damaging the body; antibiotics and other immunosuppressive drugs added to feed, etc.
Drug factors: First, abuse of antibiotics. Long-term, large-dose, and compound addition of antibiotics to prevent swine diseases causes pigs to develop drug resistance, increases the detoxification burden on the liver and kidneys, damages the normal functions of the liver, kidneys, and gastrointestinal tract, and thereby reduces the pigs' ability to resist diseases. Second, improper medication during treatment. Extensive use of antipyretic and analgesic drugs and immunosuppressive drugs such as dexamethasone treats only the symptoms, not the root cause, aggravates the condition, and accelerates death.
Immunological factors: failure to attach importance to routine programmatic and scientific immunization with vaccines (bacterins), resulting in poor immunity of pigs after immunization; improper storage, transport, and use of vaccines causing immunization failure; indiscriminate injection of vaccines, coupled with poor disinfection, causing expansion of the epidemic or increased deaths; use of antiviral, immunosuppressive drugs, and antibiotics before and after vaccine (bacterin) immunization causing ineffective immunization.
Environmental factors: non-standard construction of pig farms; unreasonable formulation of disinfection systems and procedures, and inadequate implementation of systems; failure to attach importance to rodent, mosquito, and fly control, and keeping dogs and cats on pig farms, causing spread of epidemic sources; breeding pigs carrying pathogens themselves, with inadequate monitoring, culling, and purification; selling pigs as soon as they are sick, spreading epidemic sources, so that when one household's pigs become sick, the neighbors suffer.
Prevention
Scientific feeding and management are the prerequisite. Large-scale pig farms should implement scientific production processes and standardized feeding; farmers and small-scale pig farms should use premixes produced by standardized enterprises with standardized nutrition. Immunization is the key to disease prevention. Formulate a scientific and standardized immunization program based on local epidemic conditions, and verify it on site so that it can provide uniform and consistent immunity for the pig herd in the region and on the farm. Drug health care is the guarantee. Drug prevention is very necessary because there are many types of diseases that may occur on pig farms, and it is impossible to immunize against all of them with vaccines. Moreover, effective vaccines (bacterins) have not yet been developed for many diseases. When there is no disease, antibiotics should not be used for prevention; probiotics and traditional Chinese medicine health care are advocated. For high fever syndrome, every 2 weeks, use 100 ml of Yuanlan Wutai plus 50 kg of water and let the pigs drink freely for 1 day, and use 200 g of Lanyuan Reduqing mixed into 100 kg of feed and let the pigs eat freely for 2 days for prevention; in hot weather, add 100 g of Yingji Su'an per 100 kg of feed and let the pigs eat freely to reduce stress reactions. At the same time, pay attention to strengthening disinfection. Formulate a scientific disinfection system and ensure its implementation is in place; regularly test and cull virus-carrying breeding boars and sows to purify epidemic sources; use mechanical rodent control; mix Qiangshou (main ingredients: cyromazine, etc.) into feed at 500 g per ton of feed, and mix according to the program to prevent mosquitoes and flies; dogs and cats are prohibited on pig farms. Once swine high fever syndrome occurs, report it promptly to the local government in accordance with the provisions of the Animal Epidemic Prevention Law, and decisively and rapidly extinguish the epidemic according to the principle of "early, fast, strict, and small."
Treatment
I. Treatment of high fever syndrome caused by classical swine fever virus accompanied by porcine reproductive and respiratory syndrome virus, circovirus, pseudorabies virus, Streptococcus, Pasteurella, Haemophilus parasuis, Eperythrozoon, and Toxoplasma: emergency immunization. For pig farms where classical swine fever vaccine immunization is uncertain or has not been done, emergency immunization with double-dose attenuated lapinized classical swine fever vaccine should be carried out under strict disinfection and precautions. Mix drugs into feed. Mix 200 g of Lanyuan Reduqing and 2-5 kg of glucose into 100 kg of feed, and let the pigs eat freely for 3-5 days. Inject pigs that do not eat. Use Xuechongke (main ingredients: sulfamonomethoxine, etc.) by intramuscular injection at 0.2 ml per kg of body weight, continuously for 2-3 days; Yuanlan Wutai by intramuscular injection at 0.4 ml per kg of body weight for the first time, then 0.2 ml, twice daily when body temperature is high, once daily after it decreases, continuously for 5 days.
II. For diarrhea and persistent high fever caused by classical swine fever accompanied by Salmonella paratyphi in piglets, in addition to emergency immunization with double-dose attenuated lapinized classical swine fever vaccine, separately inject Yuanlan Wutai (same dosage as before) and Jinfu Qi'an (main ingredient: florfenicol) intramuscularly at 0.2 ml per kg of pig body weight, once daily, continuously for 3 days; at the same time, for the whole herd, use Lanyuan Reduqing (same dosage as before) and 50 g of florfenicol mixed into 100 kg of feed, and let the pigs eat freely for 5 days.
III. Symptomatic treatment: if accompanied by hindlimb paralysis, use Cefaclor (main ingredient: lincomycin) at 0.2 ml per kg of pig body weight and Yuanlan Wutai at 0.2 ml per kg of pig body weight by intramuscular injection, twice daily, and Vidine colloidal calcium (for adult pigs) 5 ml by intramuscular injection, once daily, continuously for 5 days; if accompanied by respiratory symptoms, use Changxiao Mixian (main ingredients: oxytetracycline, etc.) at 0.2 ml per kg of pig body weight and Yuanlan Wutai at 0.4 ml per kg of pig body weight, by intramuscular injection once daily, continuously for 2-3 days; if accompanied by neurological symptoms, in addition to intramuscular injection of Xuechongke and Yuanlan Wutai, Qingkailing or Anxiu injection should also be used in combination for treatment. During treatment, attention should also be paid to oral or intravenous fluid replacement to improve the therapeutic effect.
At present, the causes of swine high fever syndrome are already very clear. As long as the principle of prevention first is adhered to, disinfection is institutionalized, immunization is programmatic, and correct drug prevention and treatment are carried out, and the "five early" measures of "early discovery, early diagnosis, early treatment, early isolation, and early elimination of sources" are implemented, and the 24-character policy of "strengthen leadership, close cooperation, rely on science, prevent and treat according to law, mass prevention and mass control, and decisive handling" is carried out, high fever syndrome is not difficult to control.