Efficacy comparison of 2 different PRRS MLV type 2 vaccines in a commercial farm in Thailand

The PRRS vaccines have been considered as a part of the tools to control PRRSv problems. Several commercial type 2 PRRS vaccines are available in the Thai swine industry. The aim of this study is to compare the efficacy of PRRS vaccines type 2 vaccination in piglets in a commercial farm in Thailand.

The retrospective study was observed in 1,300 sows farrow – nursery farm with conversional system located in Chonburi province, the eastern part of Thailand. Farm has been stabilized herd by mass vaccination with Ingelvac PRRS MLV for 4 years. To minimize losses in nursery and finishing period, piglets PRRS vaccination was applied at 2 weeks and PCV2 and Mycoplasma as Flexcombo at 3 weeks then pigs are weaned at 24 days of age. A total 9,028 pigs were included in this study; 4,346 pigs vaccinated by PRRS vaccine Type 2 and 4,682 pigs were vaccinated with Ingelvac PRRS MLV. Both observation groups were vaccinated at the same age and raised under the same conditions. The mortality in the finishing site farm (8-24 weeks) was recorded as the primary parameter and analyzed by Chi Square Test and Fisher’s Exact Test through the SAS System.

With respect to the mortality, there was a significant statistic difference between each PRRS vaccine group; p< 0.001. The mortality of PRRS MLV Type 2 vaccine group ranged from 8.9% to 31.0% (Mean 17.23%). When the farm changed vaccine to Ingelvac PRRS MLV the mortality decreased from 7.4% to 2.9% (Mean 4.9%).

The results of this study demonstrated that Ingelvac PRRS MLV® vaccine had a significantly better efficacy in grower-finisher pigs. This also marks the importance of considering using specific PRRS vaccines against PRRS field virus as measured by grower - finisher mortality reduction.

Disclosure of Interest: None Declared.