Molecular markers associated with response to vaccination against Porcine Reproductive and Respiratory Syndrome virus in a commercial swine farm from southern Sonora

Abstract

Porcine Reproductive and Respiratory Syndrome (PRRS) is a viral disease that seriously affects the swine industry. The main method of control is vaccination, which has shown variable effectiveness partly attributed to genetic variability in sows. The objective was to validate single-nucleotide polymorphisms (SNPs) associated with  performance traits following PRRS vaccination in replacement sows. A population of 100 Landrace(¾) / Yorkshire(¼) commercial line sows of 6 months of age, an average weight of 108 kg, and negative for PRRS virus were used. After an acclimatization stage, sows were vaccinated against PRRS (day 0). Daily weight gain (DWG) and rectal temperature (RT) were recorded on days 0, 7, 14, 21, and 28. A blood sample was individually collected on day 40 and used for DNA extraction and genotyping of 59 SNPs. These SNPs were previously identified through genomic analysis as associated with a vaccination response indicator. The 59 SNPs were validated in this study using a statistical mixed-effects model that included DWG or RT as response variables. From 59 SNPs, 5 of them were associated with DWG (P < 0.05), and 3 with RT (P < 0.05). Interestingly, the SNPs in the genes DENND5A (rs81409931 and rs81216494) and COL22A1 (rs329119519 and rs81381462) were associated with both DWG and RT, and they showed a higher allele contribution effect on phenotypes. These 2 genes appeared to be functionally related to DWG; therefore, their corresponding 4 SNPs are proposed as genetic markers associated with the response to PRRS vaccination in replacement sows from southern Sonora.