Testimonial of a Swine Health Professional
Sow Farm 1
We began using MJPRRS® vaccine on a 3,700 head sow farm that had broken with a 1–?–2 family of PRRS virus (D4). The farm broke in October 2007 and continued to produce PRRS PCR positive weaned pigs through March of 2008 with 15 — 20% wean to finish mortality, despite live virus inoculation and herd closure. At the sow farm in March abortions began to increase and reached a point of 120 — 130 per week before the initial MJPRRS vaccination was delivered. Week one following MJPRRS® vaccination only 80 additional abortions had occurred. The second week after vaccination saw 40 abortions. The third week saw 15 abortions and the following weeks returned to 2 — 4 abortions. The farm has completed their booster vaccinations and is now using a prefarrowing vaccination program with 1 — 2.5% nursery and 2 — 3% finishing mortality.
Sow Farm 2
A farrow–to–finish farm on the eastern fringe of South Dakota was having PRRS recirculation every 5 — 6 months. The clinical signs would begin in the gestation barn and quickly move into the suckling piglets. Eventually the virus would settle in the first 3 — 4 weeks post–weaning and caused repeated seroconversion. Taking a retrospective look at the viral sequences revealed that every 6–month recirculation of the virus was a shift between groups D4 and D5.
We began vaccination with a D1456 S1 began in early January. On January 22nd, about 17 days after the initial MJ PRRS whole herd vaccination, there were increasing abortions and piglet quality in farrowing was deteriorating as well. At this point PRRS was suspected, but the decision was made to booster the herd again. The intent was to hasten the process of immune building/boosting while waiting for a diagnosis. A D6 PRRS (a new introduction) was confirmed and clinical signs in the herd began to slow within 5 — 7 days of the second vaccination.
It was later discovered that this virus matched others from nearby farms and had been tracking through the region for 3 — 4 weeks prior to arrival in this farrow–to–finish unit. The farm repeated the vaccination 6 weeks after the second shot and now maintains immunity with 5 whole herd shots annually. This farm was slightly ahead of the curve with use of a D1456 S1 vaccine and realized about 6% abortions. Neighboring farms with the same virus noticed 10 — 20% abortions and much higher death loss of sows and piglets alike.
Today, the farm is still weaning PRRS negative piglets (since May–June 2012) but the growing piglets are seroconverting to PRRS at 3 — 4 weeks postweaning. A partial depopulation of the nursery in late–August of 2012 provided 12 — 15 pounds per pig during their time in the nursery and intentions are to repeat this process again in late spring of 2013 if piglets are still being weaned negative.
A system receiving rotating sources of pigs and PRRS status was having difficulty controlling mortality and fallback animals throughout the growing cycle. In a short period of time, 3 different PRRS groups had been identified and the next group of animals was due to arrive. The groups were a D4, D6, and an S3.
At the time a gamble was taken to expose the pigs to the PRRS MLV vaccine and follow this up with a single dose of MJ PRRS 3 weeks later D456 S15. The nursery was somewhat isolated from the finishing flow and chores in the nursery were only completed first thing in the morning and after a shower in the afternoon/evening.
The group responded well and had minimal nursery death loss (1.5 — 2.0% ). This group was going to a finishing barn to stand right next to pigs that were just shy of 12% mortality as a group and a similar amount being light. Even without the S3 group in the MJ vaccine, this vaccinated group of animals performed amazingly. The mortality wean–to–finish was just under 5% and this group chased the group 8 weeks older off the site.
Keith Kinsley, DVM
LiManCo - Livestock Management Company
Swine Health Center
Sioux Falls, South Dakota