Technical Key Points for Pollution-Free Classical Swine Fever Prevention in Pig Farms

1. Isolation measures Countries and regions that have eliminated classical swine fever mainly adopt measures such as prohibiting the introduction of live pigs, pork and inadequately heated classical swine fever products from countries and regions where classical swine fever exists, in order to prevent the reintroduction of classical swine fever virus. If classical swine fever cases appear, all pigs in the infected herd shall be destroyed immediately, the source of infection and possible contacts shall be traced, and contaminated sites shall be thoroughly disinfected. In areas where classical swine fever is prevalent, comprehensive epidemic prevention measures focusing on prevention shall normally be adopted. When classical swine fever is prevalent, the epidemic site shall be blockaded, the entire pig farm shall be inspected, sick pigs shall be urgently slaughtered, and the livestock sheds, environment, manure water and leftover feed shall all be thoroughly disinfected. At the same time, healthy pigs shall be urgently injected with medication, and movement of personnel within the pig farm shall be prohibited.

2. Immunization The lapinized attenuated classical swine fever vaccine is a very effective vaccine for preventing classical swine fever. Immunity is produced 7 days after inoculation, and the immune validity period is 1 year. Generally, for boars, breeding sows and growing pigs, the vaccine is injected once each in spring and autumn every year, with a dose of 1 to 2 doses, and it may also be doubled according to circumstances. Immunization of piglets may be carried out by the following two methods.

(1) For those 3 to 4 weeks old, the first immunization injection is given at a dose of 3 to 4 doses, and the second immunization is carried out at 9 to 10 weeks old at a dose of 1 to 2 doses.

(2) On pig farms where classical swine fever has occurred, newborn piglets are injected with 4 doses of vaccine before suckling, and after 2 hours they are allowed to suckle freely, after which booster immunization is given once more at 8 to 9 weeks old. When classical swine fever is prevalent, pigs with normal body temperature and no symptoms yet may be urgently vaccinated with 2 to 4 doses of classical swine fever vaccine, while pigs with high temperature and symptoms are given intramuscular injection of a large dose of classical swine fever vaccine, generally at 0.5 dose per kilogram of body weight, which may be increased or decreased according to the condition, and if necessary the injection may be repeated on the 3rd day.