Detailed Explanation of Post-weaning Multisystemic Wasting Syndrome in Pigs (Part Two)

4 Prevention and Control

PCV2 is highly resistant to inactivation by many detergents and disinfectants, and the effect of medication is limited. Therefore, it is crucial for pig farms to take measures such as changing rearing techniques, improving hygiene conditions, and reducing stress at different stages, in order to lower the "infection pressure" (including PCV2 and any other pathogens).

4.1 Farrowing Period

4.1.1 All-in/all-out, with thorough cleaning and disinfection between two batches of pigs.

4.1.2 Wash sows and deworm them before farrowing;

4.1.3 Limit cross-fostering; if it is truly necessary, it should also be limited to within 24 h after farrowing.

4.2 Post-weaning and Growing-Finishing Period

4.2.1 Pig pens should be small with solid partitions;

4.2.2 Empty out the pens and thoroughly clean and disinfect them;

4.2.3 Reduce stocking density;

4.2.4 Increase feeder space;

4.2.5 Improve air quality;

4.2.6 Improve temperature control facilities inside the barn;

4.2.7 Do not mix groups for rearing between batches.

4.3 Other Measures Adhere to a strict all-in/all-out system.

4.3.1 Strict health care measures, such as careful disinfection when cutting the umbilical cord, docking the tail, and ear-notching; iron supplementation, teeth clipping, and tail docking must be done at scheduled times; special care is required during castration; and deworming of breeding pigs and piglets must be done at scheduled times, and so on.

4.3.2 An appropriate vaccination plan, with attention to the use of antibiotics before and after vaccination, to ensure that the whole herd has a consistent and high level of immunity.

4.3.3 Keep air circulating inside the buildings, maintain a relatively stable temperature, regularly eliminate mosquitoes and rats, and prevent other wildlife from entering the pig barns.

4.3.4 Set up isolation rooms, and remove sick pigs from the production herd as early as possible or cull them, to reduce the spread of pathogenic microorganisms.

5 Treatment

The treatment effect for PMWS is very poor. At present, serum therapy has been attempted abroad and has achieved substantial success in reducing mortality. The specific method is as follows: collect blood from healthy adult pigs on farms with PMWS, extract the serum, add 0.25 mg enrofloxacin per mL, aliquot and freeze for preservation, and inject 3 mL per piglet subcutaneously 7 d after birth; the effect is very good. There are also reports that the use of immunomodulators and the feedback method brings some improvement in clinical condition, but the effect is unstable and may even worsen, which may be related to the condition of the immune system of the sick pigs.