Vaccination Strategies to Control PCV2 and MHyo Compared

Vaccinating pigs for porcine circovirus type 2 (PCV2) and Mycoplasma hyopneumoniae (Mhyo) with different vaccination strategies resulted in differences in growth rate in the nursery and finishing phases but equal performance overall, according to Bergstrom and co-authors at the Kansas Swine Day 2009.

10 February 2010

4 minute read

A total of 1,995 pigs were used to evaluate the effects of two porcine circovirus type 2 (PCV2) and Mycoplasma hyopneumoniae (Mhyo) vaccination strategies and birth weight on pig performance and carcass characteristics.

The first vaccination strategy (1) was a single full dose of CircoFlex-MycoFlex (Boehringer Ingelheim, St Joseph, Missouri) at weaning. The second strategy (2) was a full dose of Circumvent and Mycosilencer (Intervet/Schering-Plough Animal Health, Millsboro, Delaware) at weaning and again 22 days later.

At a commercial sow farm, all pigs born alive for 22 consecutive days were identified individually at birth with a numbered ear tag. The dam, gender and birth weight were recorded and used to randomly allot pigs at weaning (day 0) to the PCV2/Mhyo vaccination treatments. The pigs were weaned into four consecutive nursery rooms of approximately 500 pigs each on six occasions during a 19-day period.

Pigs from each vaccination treatment were co-mingled in pens within rooms throughout the study. Pigs were moved to a finishing barn on day 74. Pigs were individually weighed on days 0, 22, 44, 74 and 156 to measure growth rate. Carcass data were obtained from a sub-sample of 420 pigs harvested on a single day (day 167).

For data analysis, individual birth weight was used to assign pigs to seven birth weight categories, each containing a similar number of observations. Therefore, data were analysed as a 2×2×7 factorial arrangement in a completely randomised design with main effects of vaccine strategy, gender and weight category.

As birth weight category increased, average daily gain (ADG) increased (P<0.01) during each weight period and overall. Percentage of culls and light weight pigs at market also were reduced (P<0.01) as weight category increased. Overall, ADG, final body weight (BW), hot carcass weight (HCW) and backfat depth of barrows were higher (P<0.0001) than gilts, whereas the percentage of culls and pigs under 215 lb and fat-free lean were lower (P<0.0001) in barrows than gilts.

From days 0 to 22 and days 44 to 74, vaccine strategy did not influence ADG. However, ADG and BW were greater (P<0.05) from days 22 to 44 for pigs vaccinated using strategy 1 than strategy 2. From days 74 to 156, pigs vaccinated using startegy 2 had greater (P>0.05) ADG than those vaccinated once with vaccination strategy 1.

There were no differences between the two vaccination strategies for overall growth performance, carcass measurements or mortality. These results are similar to those of previous experiments that demonstrated that vaccination with Intervet reduced performance in the nursery stage but improved performance in the finisher stage.

In summary, vaccination strategy, piglet birth weight, and gender all influence the growth of pigs during the nursery stage, finishing stage, and overall and should be considered to enhance overall performance, concluded Bergstrom and co-authors.

Reference

Bergstrom J.R., M.L. Potter, M.D. Tokach, S.C. Henry, S.S. Dritz, J.L. Nelssen, R.D. Goodband and J.M. DeRouchey. 2009. Effects of porcine circovirus type 2 and Mycoplasma hyopneumoniae vaccination strategy, birth weight, and gender on postweaning performance of growing-finishing pigs reared in a commercial environment. Proceedings of the Kansas Swine Day 2009, 8-20.