Boosting Your Herd

Saturday, March 11, 2023

Are your pigs up to potential health challenges?

By Colleen Halpenny

As many producers face problematic labour shortages, much emphasis has been placed on working with pigs which require less labour time.

The highest negative cost is time spent managing illness in the herd, and researchers are working to find new ways to improve swine resiliency.

Dr. Pramod Mathur, senior geneticist and director of research and development for Topigs Norsvin Canada, has seen an increasing focus on vitality in the past few years.

"Remarkable improvement has been made in traits related to efficiency and productivity. These traits are now reaching their optimum. At the same time, the trend towards lower labour continues and it is becoming increasingly difficult to manage extra piglets and fast-growing feed efficient finishers due to a shortage of labour. This explains why it is becoming even more important that pigs are self-sustaining and vital," he says.

Dr. John Harding, DVM, Department of Large Animal Clinical Sciences at the University of Saskatchewan and Western College of Veterinary Medicine, and colleagues have been praised for their work exploring the natural disease challenge model.

The natural challenge disease model, conducted from 2015 until 2020, explored the long-term effects of disease presence in a commercial setting.

"The premise behind the project was that pigs raised in nucleus and test progeny sites are typically high health status, but these pigs will be exposed to different diseases and strains when introduced into commercial farms.

"Our initial project investigated resiliency of F1 gilts. We switched from working with F1 gilts into a general resilience focus and moved on to a wean-to-finish pig model. We would bring in three-week-old piglets at weaning from high health farms and introduced them into a very conventional health status finishing barn setting," Harding says.

To keep an active exposure level, new batches of 60 to 75 pigs arrived every three weeks.

Harding explains this took advantage of the natural transfer of pathogens at peak shedding from the previous batch to the next.

Working with pigs from different genetics companies, combined with the general environmental factors through the seasons, delivered variable transmissions across the batches, and showcased the spectrum of resiliency.

"From the producer standpoint, we think about controlling diseases through vaccines and management, but with the intense public scrutiny antibiotics are under, and no new ones coming to the market with resistance on the rise, the toolbox is dwindling. We need to find new solutions," says Harding.

Biosecurity & your weakest link

With viral and bacterial challenges constantly evolving, along with traditional challenges which do not disappear, producers are under pressure year-round for best solutions.

"As pathogens wax and wane, evolve and revert, the most powerful tool we have for mitigation of disease is biosecurity. We talk about it so much, but it doesn't only pertain to keeping disease out. We really have a lot to speak about on the internal biosecurity space. How are we managing the diseases our herd has, and how do we keep it from rearing its head in a widespread way," queries Dr. Egan Brockhoff, DVM, veterinary counsellor with Canadian Pork Council and president of Prairie Swine Health Services.

For Brockhoff, vaccination protocols will always play a key role for proper internal biosecurity, but he is excited for additional focus being placed on other areas of opportunity.

Speaking highly of the acclimation space, and the uptake of producers who are putting more time into improving its management, Brockhoff reminds them that, "they need time to adjust to your feed, housing and management system, but above all to those pathogenic organisms in your herd that they may have no immunity to."

Brockhoff also feels as though the surface has only just been scratched on understanding nutrition and vet health products added to water, and how they will impact the microbiome of the pig, along with immune response.

Scott Nyenhuis, who operates a 270 sow-to-wean facility in Durham, Ont., stresses that "you need everyone else to do their part. As an owner, you rely on your employees and other consultants to take biosecurity as seriously as you do. If there's a gap, you've left yourself exposed."

Be intentional

Nyenhuis reflects on the changes to management styles in sow housing, and how the learning curve was a big transition for owners and employees.

"Now we're relying on a computer to do those early detections of illness, which does cut back on labour – but if the readings don't come in properly, or there isn't the best understanding of what those reports are telling you, it can become easy for a sow to fall through the cracks.

"You can't just be good in the barn and around the pigs – you need to have technology and software skills as well. Those are learned skills and take a huge amount of commitment from both the owner and employee to make it successful," he says.

Brockhoff feels much success can be derived from mapping out an action plan, learning from each cycle, and working to improve for the next.

"As you review your transitions and movements, really look at what was successful and what failures happened. And then ask, what can we do better next time to ensure even higher compatibility," he says.

Harding knows the industry has moved to high stocking densities and numerous transports. He suggests producers need to manage their way out of this to decrease the incidence of exposure.

"If we look after the basics like proper ventilation, humidity and water access – then the pigs can do a lot of the work themselves. But for many, we are working in barns that are stocked even heavier than they were ever meant to be.

"So, we need to look at what our goals are 15 years from now. It's hard to manage today versus tomorrow's needs, but you could cut your herd by 15 per cent to have better returns because productivity per head will be increased," he says.

In-house multiplication

"The best insurance policy you can give yourself, and how you really get your herd to that next level, is in-house multiplication," says Nyenhuis.

For Nyenhuis, eliminating the potential exposure risks from outside introductions, and working with the genetics of those who have already proven their worth, is worth the financial investment in additional facilities and purebred semen.

"It's obviously not for everyone, and there are situations where, during expansions or repopulations, you need to bring in those outside numbers. But I've decided to look at it as though I'm not exposing my best to anything that could negatively impact them, or working with subpar gilts who aren't going to be successful," he says.

Access to genetic testing and increased reporting, something that traditionally was not a widespread focus, has positively impacted the industry, says Harding.

Further research is taking place based on his natural disease challenge model, led by Dr. Michael Dyck, Faculty of Agricultural, Life and Environmental Sciences at the University of Alberta.

Dyck's research will validate biological and genomic indicators of disease resilience in commercial pork production that can be measured and implemented in genetic improvement programs. This will involve validating promising disease resilience indicator traits and genomic tests in pigs that are exposed to pathogens in a controlled environment.

This is expected to increase the rate of genetic improvement in pig health by 30 per cent, increase the production of high value pork products, and improve the competitiveness in export markets.

"Pigs' resiliency is really important for our Canadian industry, and the natural disease challenge model, with the work of researchers, have given the breeding companies tools to improve this genetically," says Frédéric Fortin, genetics manager of Centre de développement du porc du Québec, who oversees the pigs involved in these trials.

Brockhoff recommends producers looking to bolster their herd start those conversations with their genetics advisors.

"The days of simple breeding conversations are gone. Top trait discussions are happening with the genetic companies as we explore sow mortality, prolapse, and longevity, to name a few. These aren't phenotypic traits; they are genotypic.

"Understanding resilience at the gene level needs to be in the producers' hands.

"A dramatic shift is happening in the industry where we are seeing the uptake of genetic analysis – exploring what genes these pigs have that will offer a disposition to disease prevention, robustness, pelvic strength or optimal foot health," he says.

In 2018, Topigs Norsvin implemented selection for increased natural resistance to PRRS by including breeding values for partial PRRS resistance into the selection index.

Breeding values are calculated based on WUR SNP genotype, a genetic marker for a major gene associated with natural resistance to PRRS. Pigs with the favourable genotype are better able to cope with the PRRS virus infection and this results in better performance following infection, and therefore, reduces the overall economic impact of the disease.

"Moving away from individual management to a broader, one health, whole herd approach, is going to see our industry make huge strides," says Brockhoff. BP