- 10 minutes
- Expertise article
- V. Normand, A. Lebret, I. Messager, C. Chevance, F. Bouchet, P. Berton, M. Brissonnier, G. Boulbria
V. Normand1, A. Lebret1, I. Messager2, C. Chevance1, F. Bouchet1, P. Berton1, M. Brissonnier1, G. Boulbria1
1PORC. SPECTIVE, Swine Vet practice, Noyal-Pontivy, France 2Boehringer Ingelheim, 16 rue Louis pasteur, 44119 Treillières, France
Background and Objectives
The aim of the study was to calculate the time to PRRSv-stability (TTS), the time-to-baseline-production (TTBP) and total losses in a European context.
Material and Methods
The study was conducted in a breeding 1000-sow herd, conducted in 10 batches (farrowing each 2 weeks, weaning age at 21 days). After the detection of the contamination by a PRRSv-1 strain in January 2018, a mass vaccination protocol, using ReproCyc ® PRRS EU, associated with strict internal biosecurity measures was implemented aiming to achieve PRRS stabilization. The success of the vaccination protocol was determined as the failure to detect PPRSv RNA in serum of pre-weaning pigs by RT-PCR, tested in 4 different batches.TTS is defined as the time in weeks taken to produce PRRSv negative piglets. Day 1 was the day of the 1st mass vaccination.TTBP is defined using statistical process control methods to represent time to recover the number of pigs weaned per batch that the herd had before PRRSv contamination. The data from the 20 batches prior to the outbreak were used as baseline data. A kappa (weight) of 0.400 and 3 sigma were used to define the control limits (according to Linhares 2017).Total losses was measured by the number of pigs not weaned per 1000 sows between the time of PRRSv detection until TTBP was reached.Statistical analysis were performed using SAS 9.2 software.
Results
TTS was 22 weeks, TTBP was 7.66 weeks and total losses were 2421.68 piglets.
Discussion and Conclusion
This study is the first one, in our knowledge, aiming to calculate TTS, TTBP and total losses in our European context. Face to a PRRSv-1 contamination in a naïve herd, TTS and TTBP were below those previously described in the US after a PRRSv-2 outbreak but total losses calculation was similar.