(1) Specific epidemic prevention measures
It mainly includes two aspects: on the one hand, preventive measures in peacetime; On the other hand, it is a measure to put out infectious diseases.
① Preventive measures at ordinary times
Strengthen the feeding management of cows, give corresponding feed nutrition according to different types of cows, and improve the body resistance of dairy cows. Try to adhere to the principle of self-reproduction and self-support, and introduce good cows. If it is necessary to introduce dairy cows, they must be imported from non-epidemic areas and quarantined according to their heads to prove that there are no infectious diseases before they can be introduced. Before entering the cattle, it needs to be observed in isolation for two months, and if necessary, it needs to be quarantined again to prove that there is no infectious disease before it can be mixed with the original cattle. Establish a system of isolation and disinfection of cattle farm, and close the entrance of cattle farm. The gate of dairy farm can't be unblocked, so isolation must be set up. Personnel and vehicles entering the farm must be disinfected. The disinfection pool always keeps the effective concentration and quantity of disinfectant (2% caustic soda or 4% lysol, and quicklime can be used in winter). Personnel should use ultraviolet disinfection lamp for about 10 minutes or wash their hands with 0.2% sodium hypochlorite. Cowshed, surrounding environment, playground floor, drinking trough, feeding trough or feeding passage should be carefully cleaned and scrubbed, and then disinfected with disinfectant (such as Baidusha, 12 10 disinfectant, 84 disinfectant, sodium hypochlorite, etc.). ). Establish a regular quarantine and immunization system to find out the source of infection and protect healthy cattle. Dairy farms quarantine brucellosis and tuberculosis twice a year in spring and autumn. Foot-and-mouth disease vaccine is injected twice a year. If there are other infectious diseases in the local area, negative cattle should also be vaccinated after quarantine (such as epidemic fever vaccine, anthrax vaccine, brucellosis vaccine, mucosal disease vaccine, etc.). ). If cattle are imported from other places, healthy cattle will be immunized according to local actual conditions after quarantine, and positive cattle will be eliminated at the same time.
(2) fire fighting measures when infectious diseases occur.
Cattle with infectious diseases should be isolated immediately. During the isolation period, continue to observe and diagnose, and give symptomatic treatment when necessary. Isolated sick cows should be raised and cared for by special personnel, and special feeding equipment should be used. It is forbidden to contact healthy cows. Report the epidemic situation in time. When a notifiable infectious disease is found, it should be reported to the superior business department in time, and the species of sick animals, the onset time, the onset place, the number of onset heads, the number of deaths, clinical symptoms, pathological changes after autopsy (autopsy is prohibited for acute infectious diseases such as anthrax, and disinfection should be done under special circumstances to prevent the spread of environmental pollution), newly diagnosed pathogens and preventive measures taken. If necessary, the neighboring areas should be notified to prevent the spread of epidemic diseases. Thoroughly and thoroughly disinfect the cowshed, activity place and contacted appliances where the sick cattle are located. The feed contaminated by sick cows is destroyed after disinfection, and the feces discharged from sick steaks should be concentrated in designated places for accumulation, fermentation and disinfection. Clinical examination should be carried out on other cows in the same house or group one by one, and serological diagnosis should be carried out when necessary, so as to find sick cows as soon as possible. In order to protect healthy cattle, it is necessary to carry out emergency immunization for cattle with no clinical symptoms and negative serological diagnosis. Dead cattle carcasses should be treated harmlessly, destroyed, burned or buried deeply in strict accordance with the provisions of the epidemic prevention law. Seriously ill cows and sick cows with no therapeutic value should be eliminated in time in order to eliminate the source of infection as soon as possible. When a serious infectious disease occurs, it should be reported to the relevant government departments to designate epidemic areas and epidemic spots, and after approval, it should be blocked within a certain range to avoid the spread of the epidemic. The blockade action should be decisive and rapid, the blockade scope should not be too large, and the blockade measures should be strict.
(2) The epidemic characteristics and prevention principles of some infectious diseases.
① Foot-and-mouth disease is caused by foot-and-mouth disease virus, which mainly infects cloven-hoofed domestic animals and cloven-hoofed wild animals. It is an acute, hot and highly contagious infectious disease characterized by blisters and erosion of oral cavity, hoof and breast skin (mainly nipples). Although it is mostly benign, it is a serious infectious disease because of the large number of susceptible animals, rapid spread, wide epidemic range and zoonosis. The main epidemic characteristics of the disease are strong infectivity, many sources of infection, fast epidemic speed, high incidence rate and low mortality rate, and it has certain seasonality. Therefore, comprehensive measures are mainly taken to kill sick animals, eliminate the source of infection, and vaccinate according to the type of epidemic virus. At present, effective vaccination can basically control the continuous development of the disease.
② Brucellosis is a chronic infectious disease caused by Brucella, characterized by abortion, postpartum infection and joint swelling and pain. Sheep, cattle and pigs are susceptible animals. The disease can be transmitted from susceptible animals to people, especially sheep type, which is the most contagious and harmful. At present, the disease has an obvious upward trend in some areas of China, especially in pastoral areas. The disease can be preliminarily diagnosed by the pathological changes of abortion and aborted fetus and placenta, and the diagnosis needs serological tests (plate agglutination test, tube agglutination test and total mammary ring test). The prevention and control principle of the disease is to introduce improved cattle into the customs, quarantine twice a year, and eliminate positive cattle and sick cattle in time. Vaccinate S 19 (cattle) when necessary (Brucella vaccine has residual toxicity and can cause human and animal infections, so it should be well protected and strictly disinfected when used). It is necessary to isolate the aborted cows, diagnose them as soon as possible, and isolate the calves of sick cows.
③ Tuberculosis is a chronic infectious disease caused by Mycobacterium tuberculosis, characterized by nodular granuloma and caseous necrosis. Cattle are the most susceptible among domestic animals, especially cows. Tuberculosis between humans and cattle can be transmitted to each other. Mycobacterium tuberculosis is divided into bovine type, human type and avian type. Bovine tuberculosis is mainly caused by bovine tuberculosis, but it can also infect human and poultry bacteria, but its pathogenicity is weak. Bovine bacteria mainly infect cattle, pigs and people, but not poultry. Human-type bacteria mainly infect people, cattle and pigs, but not poultry. Avian bacteria mainly infect birds, but also cattle, pigs and people. The main diagnostic points of the disease are: progressive emaciation, swollen lymph on the body surface, abnormal auscultation and percussion in the lungs and intractable diarrhea. The quarantine method is mainly to observe the allergic reaction by intradermal injection of purified bovine tuberculin. The disease is mainly prevented by quarantine, isolation, disinfection, culling and feeding healthy calves.
④ Paratuberculosis, also known as Paratuberculosis Enteritis, is a chronic infectious disease mainly occurring in cattle, characterized by intractable diarrhea, gradual emaciation, thickening of intestinal mucosa and chapped formation. This disease may exist in general cattle-raising areas. The early symptom is intermittent diarrhea, and later it becomes recurrent intractable diarrhea. The excrement is thin and smelly, with bubbles, mucus and blood clots. I had a normal appetite and a good spirit in the early stage. Later, the appetite decreased, the eye socket gradually sunken, the spirit was bad, the milk yield gradually decreased, and finally stopped completely, with rough skin, rough hair, mandibular edema, drooping skin and constant body temperature. Diarrhea sometimes stops, excrement returns to normal, weight increases, and then diarrhea. Giving green feed will aggravate the symptoms of diarrhea. If diarrhea persists, it can fail and die after 3 ~ 4 months. Sick cows often have symptoms in the late stage of infection, so it seems meaningless to treat them with drugs. In order to prevent this disease, we should strengthen the management of feeding, especially pay attention to giving young cattle sufficient nutrition and enhancing their resistance, and do not introduce cattle from epidemic areas. If it has been introduced, it must be checked and confirmed to be healthy before it can be mixed. On the basis of observing the supposed healthy cows with medical history at any time and conducting regular clinical examination, all cows are examined once every three months every year. Those who pass the examination for three consecutive times can be regarded as healthy cows, while those who fail the examination and those with obvious clinical symptoms should be culled in batches. Polluted cowsheds, railings, feeding troughs, utensils, ropes, sports fields, etc. should be sprayed or cleaned with disinfectants such as quicklime, lysol, caustic soda, bleaching powder and carbolic acid; Feces should be piled up and fermented at high temperature to make fertilizer.
⑤ Salmonella disease, also known as paratyphoid fever, often manifests as septicemia and enteritis, and can also cause abortion in pregnant women. Not only does it pose a serious threat to livestock reproduction and the health of young animals, but some salmonella can also infect people and cause food poisoning, which should be paid attention to. Symptoms: Adult cattle often start with high fever of 40 ~ 465438 0℃, coma, loss of appetite, frequent pulse, dyspnea and gradual decline of physical strength. Most cases have blood clots in the feces 12 ~ 24 hours after the onset of diarrhea, which quickly turns into dysentery, and the feces are smelly, containing cellulose tablets, and occasionally mucus lumps or mucous membranes are discharged. After the onset of diarrhea, the body temperature drops to normal. Most of them died within 1 ~ 5 days. The patients with prolonged illness appeared dehydration, emaciation, sunken eye sockets, mucosal congestion and yellowing, abdominal pain in sick cows, abortion in pregnant cows (this bacterium was found in aborted fetuses), some cases could be recovered, some cows had fever, loss of appetite, listlessness and reduced milk production. After 24 hours, these symptoms can be alleviated. There are also some cows that can't be seen or touched. They just excrete germs from their feces, but after a few days, they no longer excrete germs. The main pathological changes are hemorrhagic enteritis and pneumonia. Calves: If there are cows with bacteria in the herd, they can refuse to eat, fall to the ground within 48 hours after birth and quickly fail, and often die prematurely within 3 ~ 5 days. There was no special change in autopsy, but Salmonella could be found in blood and viscera. Most calves get sick at 10 ~ 14 days after birth, and their initial body temperature reaches 40 ~ 4 1℃. After 24 hours, the grayish yellow liquid feces mixed with mucus and bloodshot are discharged, and they usually die within 5 ~ 7 days after onset. Sometimes the mortality rate can reach 50%, and sometimes most of them can be recovered. Wrist and tarsal joints with a long course of disease may be swollen, with symptoms of bronchitis and pneumonia. Prevention: we should strengthen the feeding management of this disease, eliminate the inducement, keep the feed and drinking water clean and hygienic, and use calf paratyphoid vaccine. Treatment: oxytetracycline, sulfamethazine, etc. Can choose and symptomatic treatment, such as infusion, can strengthen the heart. Salmonella can be transmitted to people, such as poisoning caused by eating dairy products that are not fully heated and disinfected by sick animals and infected animals. The incubation period is 7-24 hours, which can also be extended to several days. The more bacteria, the stronger the virulence, the earlier the symptoms appear, sudden fever, elevated body temperature, accompanied by headache, chills, nausea, vomiting, abdominal pain and severe diarrhea.