Genetic Line Influences Growth Rate Responses to Vaccination for PCV2

Pig genetic line affected the response to porcine circovirus type 2 (PCV2) vaccination in terms of growth response in a study carried out in Kansas. The mean weight difference between vaccinated and control pigs was almost four times greater in the purebred Durocs than a synthetic White Pietrain line on day 130. This difference should be considered a risk factor for the expression of this disease, the researchers said.

1 March 2012

3 minute read

By: Jackie Linden

In a paper published recently in Journal of Swine Health and Production, Megan L. Potter from Abilene Animal Hospital in Abilene, Kansas, and co-authors there and at Kansas State University report a new study into the effects of PCV2 vaccination on growth rate, backfat depth and loin depth of pigs in a high–health herd that contained different genetic lines.

They used a total of 454 pigs (20.6±1.98 days of age; 6.1±1.27kg bodyweight) in a 130–day randomised controlled field trial.

Genetic designations were A×A (Duroc line), B×B (synthetic White Pietrain line), A×B, and B×A. Pigs were randomly assigned to vaccination treatments (vaccinated or non–vaccinated control) within litter by gender (boar or gilt).

Vaccinated pigs received two doses of a PCV2 vaccine at three and five weeks of age (Circumvent PCV; Intervet/Schering-Plough Animal Health). Serum samples were collected and pigs were individually weighed on days 0 (weaning), 40 and 130 to determine PCV2 viral load, antibody level and average daily gain. Data were analysed from 417 pigs with complete growth records.

The higher average daily gain from day 0 to day 130 for vaccinated pigs depended on the genetic line; genetic line–by–vaccination interaction was P<0.05. The mean weight difference between vaccinated and control pigs was almost four times greater in the A×A pigs than in the B×B pigs on day 130.

On average, compared with control pigs, vaccinated pigs had lower serum PCV2 viral load levels on days 40 and 130 (P<0..001).

Pig genetic line affects growth rate response to PCV2 vaccination and should be considered a risk factor for the expression of circovirus disease, concluded Potter and co-authors.

Reference

Potter M.L., L.M. Tokach, S.S. Dritz, S.C. Henry, J.M. DeRouchey, M.D. Tokach, R.D. Goodband, J.Nelssen, R.R.R. Rowland, R.A. Hesse, R. Oberst, J. Anderson and M. Hays. 2012. Genetic line influences pig growth rate responses to vaccination for porcine circovirus type 2. J Swine Health Prod. 20(1):34–43.