Pay attention to the prevention and treatment of respiratory diseases in pigs in winter

Winter is the season of frequent occurrence of swine respiratory diseases, which cause serious economic losses to many pig farms, such as slow growth rate, reduced feed return, increased mortality, delayed marketing and vicious circle in management.

I. Occurrence characteristics

1. Multiple pathogens mixed infection. Porcine respiratory tract diseases are caused by the interaction of virus, bacteria, parasites, environmental stress and low immunity of pigs, and few of them are caused by single factor clinically. Therefore, a series of syndromes, called porcine respiratory disease syndrome (PRDC), appear in pig respiratory system. It is often a double or multiple infection between virus and virus, virus and bacteria, bacteria and bacteria. Such as porcine reproductive and respiratory disorders syndrome and porcine postweaning multisystemic failure syndrome.

2. A large proportion of swine respiratory tract diseases changed from acute to chronic, which was difficult to eradicate in pigs and became frequent and frequent diseases, and the harm became more and more serious.

3. Complicated and serious disease, increased mortality, acute onset, rapid spread.

4. Stress is an important trigger. Such as climate change, pig breeding density is too large, weaning, mixing, transfer, long-distance transportation of pigs, excessive temperature change, excessive humidity, poor ventilation, poor air quality (ammonia, hydrogen sulfide, carbon dioxide is too high), etc.

II. Prevention and control measures

1. Integrated control measures. (1)Insist on self-propagation and self-cultivation. Establish stable breeding herd, not easy introduction. If it is necessary to introduce, first of all, to clarify the epidemic situation of the pig farm introduced, in addition, serological testing should be carried out, negative pigs can be introduced, and the introduction of positive pigs with virus is strictly prohibited. After introduction, appropriate isolation areas must be established and monitoring work should be done well. Generally, isolation and quarantine should be carried out for 4~5 weeks. Healthy people can be raised in mixed groups. (2)All in and all out. At least two stages of delivery room and nursery should be fully in and out. (3)Establish and improve the biosafety system of pig farms. Regular disinfection of pig houses and environment, keeping pig houses, feeding management tools and environment clean and hygienic, on the one hand, can prevent the introduction of external diseases, on the other hand, through strict sanitary disinfection measures to reduce the contamination of pathogenic microorganisms in pig farms to the minimum, can control and reduce the incidence of infected pigs and the opportunity of secondary infection to the maximum extent. (4)Do a good job in pig breeding management. The feeding and management of pig herd at each stage should be done well to ensure the nutritional level of pig herd, and the feeding of moldy and rotten feed should be prohibited to improve the immunity of pig herd, thus reducing the incidence of secondary infection and the resulting loss. (5)Immunization against major diseases. Such as swine fever, pseudorabies and swine asthma immunity. (6)Closed management is adopted in pig farms. The pig farm prohibits all outsiders from visiting and reduces the flow of people and goods. Breeders should minimize mobility. Reduce the number of entries and exits, and prohibit the use of production tools.

2. Preventive measures. (1)Control of primary diseases. Porcine asthma, porcine reproductive and respiratory syndrome (blue ear disease), porcine circovirus type 2 disease, swine influenza, etc. are considered to be the prime causes of swine respiratory diseases (primary diseases). Therefore, in the prevention of respiratory diseases, the primary disease must be effectively controlled first, and other respiratory diseases may be reduced accordingly. These diseases are related to immunosuppression. In order to improve pig immunity, Astragalus polysaccharide injection combined with vitamin B1+B12+C intramuscular injection, or Astragalus polysaccharide and multi-dimensional drinking water. Of course, antiviral preparations such as interferon and leukocyte-mediated cytokines can also be appropriately selected for treatment, or combined with some Chinese herbal antiviral preparations. (2)Prevention with commonly used drugs. Lactating sows: Antibiotics can be added to sow feed before and one week after sow delivery, and 400g of "Jiakang" can be added to each ton of feed for prevention; or "Zhiyuanjing" 100ppm/ton + aureomycin 300ppm/ton can be added to reduce the contamination of sow discharge bacteria, cut off the horizontal transmission of diseases from sow to piglet, and insist on prevention over treatment to ensure the health of "mother and child". Suckling piglets: long-acting oxytetracycline injection, such as "Demixian" and "Aituda", was injected into suckling piglets at the age of 21 days to prevent the occurrence of digestive and respiratory diseases in suckling pigs. Weaning piglets: adding antibiotics to piglet feed from 1 week before weaning to 4 weeks after weaning, adding "Jiakang" according to 300~400 grams per ton of feed, or adding "Zhiyuanjing" 100ppm+ aureomycin 300ppm/ton, or using "Junkang"(clindamycin + spectinomycin + immune enhancer)1~2 kg/ton to cut off the horizontal transmission of diseases between piglets and piglets, which has obvious effect on preventing various bacterial diseases and mycoplasma. The above drugs can be used in turn, and each drug can be used for 2 to 3 months. Growth and breeding period: effective drugs should be used for prevention at 12~13 weeks and 17~18 weeks of age, but drugs that produce false positive clenbuterol hydrochloride should be avoided."Jiakang" can be added according to 300~400 grams per ton of feed, or "Junkang" 1 kg/ton. Pulse administration is adopted for 1 week continuously. After 1 week of drug withdrawal, the drug is re-administered for 1 week. Reserve pigs: adding drugs to reserve pig feed to purify pathogens in vivo. 100ppm tiamulin and 300ppm aureomycin (100mg doxycycline)/kg feed, or "Jiakang", added at 200 - 300 g per ton of feed, one week per month, directly fed until mating.