Veterinary session

Evolution of large-scale swine herds made effective biosecurity measurements essential. In our study, we surveyed the external and internal biosecurity, the used disinfectants and hygienic tools of 19 Hungarian large swine farms (altogether 30,719 sows) by using a questionnaire between November 2020 and March 2021. Each questionnaire was completed during an interview in person or via videochat with the veterinarians and/or farm managers.

Results showed that 26% of the farms were completely closed (no animal purchase), the others were in cooperation with carefully chosen permanent partners, and the purchased animals were quarantined for at least 60 days, but only 11% of the surveyed farms had a separated quarantine facility outside the farm. Regarding external biosecurity, the most common risk factor was the proximity between swine farms: only 28% of the surveyed herds were the only swine farm within a 3 km radius and 21% of them had a neighbouring farm in a distance of less than 500 meters. Only 58% of the farms managed to load live animals for transportation in the fence-line while this number is 32% in case of feed. The transportation vehicles were disinfected at the entrance in 48-69% of the farms. As regards to showering and downtime the entrance of people to the herds was sufficient on almost every farm; none of the farms allowed people to enter the facility without changing clothes and visitors were obligated to have downtime of at least 2, most commonly 3 nights since the last connection with pigs.

Considering internal biosecurity, all in-all out systems were widely used but the length of the service period before the following batch was usually short, in case of the farrowing rooms less than 4 days in 81% of the farms, which does not facilitate sufficient disinfection. Workers’ movements inside the facility were usually performed in the direction of younger to older animals in most of the farms, thus they are exposed to less risk. On the other hand, 58% of the farms had no tools which were exclusively used in the different rooms, so they are regularly carried among different groups of animals. Disinfection protocols were usually performed with a combination of disinfectants. The most common agents were aldehydes, peroxides, alcohols and detergents. UV-light was also a widely used method to disinfect personal belongings.

It can be concluded that risk factors related to the location of the farm can be minimised by installing HEPA-filters to the barns. Limited vehicle entry could be achieved by installing the relevant infrastructure in the fence-line and if necessary, purchasing of a vehicle that is exclusively used inside the farm. Strict all in-all out management is possible by the implementation of the farm rotation plan and avoiding any capacity overrun of the houserooms.