543
Genetic Parameters and Effects for a Major QTL of Piglets Experimentally Infected with a Second Porcine Reproductive and Respiratory Syndrome Virus
Blood samples were collected and weights
recorded periodically for 42 days on commercial crossbred
piglets for 4 trials, each of ~200 pigs, after being infected
with Porcine Reproductive and Respiratory Syndrome
Virus isolate KS-2006-72109. Blood samples were used to
measure serum viremia, which was used to compute viral
load (VL) from 0-21 days post infection. Heritability
estimates of VL and weight gain from 0-42 days post
infection (WG) were 0.65 and 0.44. Estimates of
phenotypic and genetic correlations between VL and WG
were -0.22 and -0.35. These estimates were similar to those
previously reported for experimental infection with another
PRRS virus. The effects of a SNP on SSC4
(WUR10000125) previously identified to be associated with
VL and WG were significant but smaller than observed
with the first virus, especially for WG, likely due to genetic
and pathogenic differences between the two virus strains
Keywords:
Pigs
PRRSV
Susceptibility
