In search of the perfect pig

Thursday, November 25, 2021

Genetic advances will get us there.

By Geoff Geddes

While "faster, higher, stronger" is the Olympic motto, it is "leaner, healthier and more efficient" that serves as the gold standard for the pork sector. In a business where margins are thin and progress is essential, the role of genetics to fuel that progress is a critical one. Though genetic technology is complex and fraught with challenges, it holds the key to keeping producers competitive both at home and abroad.

"Genetics are vital to our industry," Tim Nelson tells Better Pork. "As the world's population continues to grow, we must be able to produce a high-quality product at a price that is accessible to the masses."

Nelson is the executive director of PigGen Canada in Guelph, Ontario. Formed in 2009, the organization includes all of the major pig genetic companies in the country, working collaboratively on issues affecting the industry as a whole.

Stress for success

The first application of DNA technology in pigs occurred in Canada last century, when David McClellan and colleagues found the mutation that caused Porcine Stress Syndrome.

"From there, science began looking at how the genetics of a pig could be used to make improvements," Graham Plastow tells Better Pork.

He is a professor and CEO of the Livestock Gentec Center, Faculty of Agricultural, Life and Environmental Sciences at the University of Alberta.

Over the last ten years, researchers have increasingly made use of genetic markers to predict the breeding value of pigs for traits like disease resilience, feed efficiency or longevity.

Live long and prosper

"With longevity, for example, you can only measure it after the sow has lived her life," says Plastow. "If we could get that information at birth, we could make much better and faster enhance-ments to such traits."

For the most part, the focus of genetic companies over the years has been on productivity, with impressive results.

"Genetics has been responsible for huge improvements in production for several decades, and the rate of change is accelerating due to the processes and technology used by breeding companies," Brian Sullivan, CEO of the Canadian Center for Swine Improvement (CCSI), tells Better Pork.

Based in Ottawa, Ontario, the CCSI aims to enhance the ability of the Canadian swine industry to compete domestically and abroad.

One of the most visible changes for producers involves sow performance, and the numbers tell the tale.

"When I started in genetics in the early 90s, pig producers were happy to get 20 pigs/sow/year, and averaged much less," says Sullivan. "Today, the average is around 25 pigs/sow/year, with some farms reaching 30 or more."

The weighting game

Over his career, Sullivan has also witnessed a rise in market weight – from 100 kg live to 130 kg live – that he attributes largely to genetics.

"If you raised them to 130 kg back then, the last 30 kg would have been all fat," says Sullivan. "Today, they keep growing and putting on lean weight. That has been critical for the hog industry in Canada where we export five times as much pork today as we did 25 years ago, and we don't have five times as many sows, so genetics has made the difference."

In fact, genetics has impacted many areas of interest to producers, and a change in one area can necessitate improvement in another. For example, as litter sizes continue to rise, there is more variation in piglet size, leading to issues around survivability.

"Litter size is still important, but we are seeing more emphasis on the uniformity and viability of those piglets," says Sullivan. "We want to maximize the number of piglets that turn into good quality weaned pigs as they grow."

Mother knows best

Genetics is also supporting piglets by focusing on sow milk production and mothering ability. As well, with the resurgence of loose housing, it's vital to select for sows that won't lie down on their piglets and crush them.

As always in the livestock sector, consumer demand plays a large role in driving genetic priorities.

"There is always going to be that mix of growth and pork quality when it comes to our genetic focus," says Plastow. "Science needs to maintain a delicious product with the great flavor and quality that the public expects, at a price that works for both producers and buyers. At the same time, people are increasingly conscious of where their food comes from and how it is produced."

Part of the focus from consumers is on the environment, and genetics helps address that issue by enhancing feed efficiency, thereby reducing manure production and limiting environmental impact in the process.

One aspect of the pig sector has been drawing more attention from genetic researchers of late, and it's also one of the more challenging traits to address: animal health.

Health breeds wealth

"If an animal gets sick, it costs more to raise, and if it doesn't survive, the producer has lost their investment," says Plastow. "Good health also supports animal welfare and boosts worker morale when staff don't see animals suffering on their watch."

Rather than target one disease, genetics aims to enhance overall disease resilience, so that pigs are less affected by viruses and able to carry on with little or no impact on production. With opportunity, however, comes obstacles.

"To address resilience, you need models where you can test the ability of thousands of pigs to withstand a health challenge, and sustaining those models is costly," Dr. Ben Willing tells Better Pork. "There is also an ethical side to this, as we must purposely make pigs sick to study resilience."

Willing is an associate professor in the Faculty of Agricultural, Life and Environmental Sciences at the University of Alberta.

The complexity of dealing with disease is also a factor to consider. While a trait like growth performance is easy to measure, there are many variables that impact resilience.

"How pigs deal with a disease challenge could be driven not just by their current state, but by their early life history," says Willing. "We have done work looking at changing the microbial environment of pigs in their first weeks of life, and there is evidence that doing so could impact how they deal with disease when they are older."

Passing the tests

While researchers continue to explore genetic options, breeders such as Brent Robinson are seeing the benefits firsthand. Robinson owns Vista Villa Genetics, an independent breeding stock supplier in Huron County, Ontario.

"We do a lot of scanning and testing of our piglets, so we know they are growing faster and demonstrating greater feed efficiency, as they gain more weight for every kilogram of feed," Robinson tells Better Pork.

"We also track intramuscular fat that leads to marbling in pork. Genetics is like an ocean liner; you can't change direction on a dime. You need to plan well ahead for the areas you want to target, and science realized long ago that more intramuscular fat was key to producing tasty, flavorful pork, especially in the Duroc breed, so they made that a priority."

Robinson learned the breeding business from his father and has applied one of dad's guiding principles in the current operation: it's all about balance.

"Dad always said that in addition to production and efficiency, we needed pigs that are structurally sound and will give customers value for their money," says Robinson.

"Just as a decathlete must perform well in 10 different events, you need to balance genetic improvement across a variety of traits."

Based on his experience, Robinson echoes the importance of healthy piglets in the face of ever-increasing litter sizes.

"I've seen some genetic companies that are wholly focused on producing more and more piglets, but my customers would rather have 14 or 15 beautiful, uniform piglets with a healthy birthweight," says Robinson.

"Heavier weaned pigs are more robust and save a lot on expensive nursery rations. At a time when feed represents 75 per cent of our production costs, that makes a huge difference to the bottom line."

For genetic companies to build on their progress to date, the bottom line is collaboration.

"You must do a lot of things well to succeed in genetics today," says Sullivan.

"Thirty years ago, breeders just weighed pigs and measured backfat, but today they also measure intramuscular fat, feed intake, sow productivity, pork quality attributes, robustness and behavioural traits. Just keeping up with all of this is a challenge and not something that really small companies can do effectively on their own."

Thinking big

Also, genetics is not a field where you can make breakthroughs with 100 sows. To compete globally, you must have access to nucleus populations in the thousands and be well funded. Fortunately, Canadian breeders have always worked together in programs where they have access to large numbers of purebred sows, and some of them even exchange genetics to help increase diversity.

"That willingness to cooperate gives Canada a real edge globally when it comes to genetic improvement," says Sullivan.

Going forward, Sullivan sees a continued focus for genetics on traditional areas like sow productivity and quality of weaned pigs, with greater exploration of newer aspects such as environ-mental impact, animal welfare and behavioural concerns.

"How do sows adapt to loose housing?" says Sullivan. "How do they interact with other sows in that environment? Some do very well, some are aggressive and others can be quite timid; genetics has a role to play there."

From a pork standpoint, genetics could address how the lean distribution varies in a carcass, perhaps increasing the marbling in the loin without adding fat to the shoulder or making the ribs longer.

"The focus will be on adding value to the carcass and providing more of what consumers are seeking in terms of quality attributes," says Sullivan.

Like the pork industry itself, genetics is focused on sustained improvement.

Onward and upward

"Genetic technology is never standing still, as it is continually looking at how to produce more from less," says Plastow. "Each year, we do a bit better at producing animals that eat less, get to market the way producers intend and provide a fair market value for those who raise them."

Though genetics is mostly about science, there is also an art element in trying to anticipate the long-term needs of the pork industry.

"With genetics, you are improving animals for the future," says Plastow. "What genetics companies are seeing today is what producers will see tomorrow. These companies must be good at predicting what the market will demand down the road, and each company has its own take on that.

"Raised without antibiotics' seems to be catching on, but will it really take hold? There is more cost involved for producers, so it only makes sense if the product is delivered consistently. If supermarkets have it on the shelf one week and then the shelves are empty the next, it defeats the purpose. It comes down to what we need to do to get the right pigs in producer hands so they have a stable supply at the right cost and can keep the industry moving forward."

Despite the challenges, experts like Plastow see a bright future for pig genetics.

"Our focus is on getting the right quality data that enables us to use the genetic tools we have now," says Plastow.

As it stands, there are an increasing number of tools that can help in gathering that data. Sensory and imaging technology are ideal for monitoring animal behaviour, as they offer a contactless way to gather different types of information. Scientists can home in on a particular pig and track its feed con-sumption, growth rate and interaction with other pigs.

"We are able to do more and more in regard to social aspects like tail biting that lead to loss of value," says Plastow. "We can gain a window into these traits that are of greater and greater importance to consumers who want to know that livestock lead happy lives."

These technologies allow for tracking over time and seeing early signs of change in animals, such as red flags around disease if pigs are not moving around as much as they usually do. Perhaps they have changed the way they move, which could be an early indicator of lameness.

"As we gather more data, we will explore aspects like artificial intelligence and machine learning to take those data points and convert them into predictions," says Plastow. "Everything we do on the genetics side is about refining our approach, expanding our reach and driving the genetic improve-ment engine forward."

Those efforts might not result in the perfect pig, but if they lead to animals that produce more for less, satisfy consumers, preserve the environment and sustain the industry as a whole, many will say that's the next best thing. BP