If you want to kill the buzz at a party, bring up diarrhea. 

Though it’s rarely discussed off the farm, the condition is a major concern for producers, sparking science to look for solutions. 

Given the stakes, developing an alternative and environmentally friendly strategy to combat PWD and improve the overall health of pigs is imperative. Post-weaning diarrhea (PWD) is caused by a group of E. coli that produce special toxins, and is widespread in swine production today. In addition to causing stress for the animals, it does the same for their owners by harming growth performance and increasing mortality in the barn.

In many cases, farms rely on antibiotics to treat PWD. Given the rise in antibiotic-resistant bacteria associated with livestock farming, pressure is growing to phase out the drugs completely, with some countries already banning their use in feed to promote growth. Under the heading “the cure is worse than the disease”, heavy metals like zinc oxide (ZnO) have proved effective in controlling PWD, yet have come under considerable scrutiny for their negative effects on animal health and the environment. These metals can accumulate in vital organs like the pancreas and liver, and can also damage the environment by contaminating soil and water.

Probiotics: All pros and no cons

Now that we know what doesn’t work, only one question remains: what does? Based on recent studies, the addition of probiotic bacteria (live microorganisms that are intended to have health benefits when consumed) to the diet has a number of advantages for piglets during weaning: improved nutrient digestibility, reduced pathogen levels, greater gut immunity and enhanced overall growth performance.

As a further benefit, including specific probiotics in pig feed could help reduce the number of antibiotic-resistant bacteria in the intestine. One such probiotic – lactobacillus – has been studied extensively for this purpose, and is now being used in commercial applications.

The right spore for the chore

Another promising option in the PWD battle is a particular strain of Bacillus species, known as Bacillus subtilis. Bacilli are rod-shaped bacteria that can form spores and survive in harsh conditions. These bacteria are plentiful, residing in soil, water, dust and air, and will thrive in various temperatures. Furthermore, their ability to create spores at high temperatures and endure low pH (phosphorus) environments make Bacillus subtilis a robust strain that could be developed as an in-feed probiotic supplement. In recent studies, augmenting pig diets with a probiotic-based in Bacillus subtilis reduced the incidence and severity of diarrhea and enhanced growth performance by boosting immunity in weanling piglets.

If the eyes glaze over at terms like lactobacillus and Bacillus subtilis, the benefits of this study should be eye-opening for producers. Apart from addressing PWD caused by E. coli, the inclusion of Bacillus-based probiotics in nursery pig diets may reduce the presence of feed-induced diarrhea and help maintain or improve growth performance. This is significant, since weaning-associated diarrhea can also be triggered by economical diets which are mostly plant-based (corn and soybean meal-based).

Because feed cost is a huge burden on the industry, less costly regimens are often necessary, but they have also been associated with a higher incidence of diarrhea and lower intestinal integrity (the ability of the intestine to maintain its structure and function).

It takes a village

Good research is an investment in the future, so the scientists in this study were grateful for financial support from Swine Innovation Porc (SIP), Ontario Ministry of Agriculture, Food and Rural Affairs (OMAFRA) and CBS Bio Platforms Canada.

From the University of Guelph’s Department of Animal Biosciences, a number of research minds joined forces for the project: Dr. Julang Li, professor; Sudhanshu Sudan (a PhD student at the time, now a research scientist at U of G); Dr. Lee-Anne Huber, assistant professor; Dr. Robert Friendship, professor, Ontario Veterinary College; Dr. Elijah Kiarie, professor; Xiaoshu Zhan, Ph.D. candidate; Lauren Fletcher, Ph.D. candidate; and Serena Dingle, M. Sc.

Also integral to the project were Rob Patterson, vice president - Innovation & Commercialization at CBS Bio-Platforms, and the animal care and sampling assistance provided by the Arkell Swine barn staff, research associates Cuilan Zhu and Douglas Wey, and undergraduate research interns. Metabolite sample processing and data extraction were delivered by Robert Flick, Mass Spectrometry and Metabolomics Services Manager at BioZone, University of Toronto.

Based on the current results, low-dose supplementation can achieve significant improvements in growth performance in a research environment. From here, larger studies in a similar setting, as well as in production/commercial settings, must be conducted to confirm these findings.

While there is still work ahead, this study adds to a limited body of research on the use of probiotics as an alternative to ZnO and antibiotics in guarding against PWD. The results also suggest that supplementing piglets with a novel bacillus-based probiotic may improve feed efficiency and growth performance, offering an economical feeding strategy to benefit producers around the world.

As a dinner topic, that sure beats diarrhea.

The pork sector is full of acronyms: ADG (average daily gain); FCR (feed conversion ratio); and of course, BYOB. 

For producers, the one they could do without is PED. Porcine Epidemic Diarrhea, which causes vomiting, diarrhea and often mortality, has wreaked havoc on pigs around the world, and science is helping to combat it on a number of fronts. Most recently, researchers targeted a common mode of disease transmission – trailers – as they strove to improve cleaning methods and boost biosecurity in the Canadian swine transport industry.

What started as an effort to save time and money when cleaning hog trailers took on added meaning in early 2014. That was when the federal agriculture minister called industry with a chilling pronouncement: “PED is now in Canada”. The disease that first hit North America in the United States, costing their pork sector billions of dollars, was here, and producers were in panic mode.

PED prevention partners

For guidance on how to proceed, the federal government and pork producers asked the University of Saskatchewan to lead efforts to stop the transmission of PED and other diseases that can result from transporting animals.  Researchers consulted with a PED advisory committee comprised of members from across the country, including transport companies, provincial pork associations, packers, producers and swine veterinarians. 

Together, the parties identified priorities around PED prevention, starting with how to clean trailers thoroughly enough that no trace of the virus remained on board. Working with the Prairie Agricultural Machinery Institute (PAMI) in Humboldt, Saskatchewan, scientists devised a high-pressure washer and vacuum system that would reach every corner of a trailer and blast out clumps of manure or any other material that might harbour PED.

The washer was a good start, so the next step was developing a remotely controlled system that would allow complete cleaning of trucks without the need for human workers entering the trailer. This involved trying different technologies, including a small robot vehicle used by the military to pick up explosive packages and safely detonate them. Eventually, the project partnered with Truck Wash Technologies Inc. in Sault Ste. Marie, Ontario, to advance its gantry-style wash system for their purposes. This system moves across the length of the vehicle in multiple passes, simultaneously cleaning the exterior and interior of swine transport trailers.

Feeling the heat

Researchers were also tasked with finding the optimal level at which to heat trailers, so that if any trace of the pathogen remained after washing, it would be deactivated. Collaborating with VIDO-InterVac in Saskatoon, Saskatchewan, the research team concluded that heating the trucks at 75°C for 20 minutes would be sufficient to kill the threat.

Sensor-ship

The challenge with heating was that some areas of a hog trailer, such as behind gates and walls, can be harder to warm sufficiently. In response, the team looked for sensors that could be installed in trailer trouble spots and monitor temperatures. Though they found a company that specialized in sensors to assist in this effort, it overlooked one small detail: pigs eat sensors.

Undeterred, the University of Saskatchewan engineers collaborated with the sensor company, Transport Genie in Burlington, Ontario, to develop sensors and insulate them properly to protect against curious snouts. The new sensors deliver GPS traceability of swine transport trailers, continuously measure environmental conditions during transport of animals and verify that trailer trouble spots reach the required time and temperature during heat treatment.

Idle threats? Not a chance

Though the early panic from PED in Canada has subsided, it and other diseases continue to threaten the swine sector. Thanks to this project, the risk of transmitting pathogens during transport has been drastically reduced, saving producers millions of dollars per year from illness and death loss. Findings from the study have raised the biosecurity bar, and heating trailers at 75°C for 20 minutes is now the industry standard.

Based on this project, Prairie Swine Centre has developed guidelines to assist designers in considering animal welfare and biosecurity with new trailers.

As a further benefit, scientists are working with trucking companies to install their sensors, not only for biosecurity, but to warn drivers when the temperature and humidity levels are endangering their pig passengers. Apart from enhancing animal welfare, this move will aid both trucking companies and packers, as each is responsible for the pigs once in their possession.

Driven by the project lead, Dr. Terry Fonstad, Associate Vice-President Research (Ethics and Infrastructure) at the University of Saskatchewan, this study drew on funding from Swine Innovation Porc (SIP) and expertise from several corners: Prairie Swine Centre, PAMI, Truck Wash Technologies Inc., Transport Genie Ltd, the PED advisory committee and VIDO-InterVac.

Arms race

As the world learned the hard way from COVID-19, we must always stay a step ahead of the enemy. In that spirit, researchers are addressing what happens if a trace amount of virus survives washing and heating of the trailer and imbeds itself in a biofilm for self-protection. A biofilm is a thick layer of organisms that gather to form a colony.

With the attention garnered by their findings, researchers are now fielding calls from the Canadian Food Inspection Agency (CFIA) about other diseases of concern, such as African Swine Fever (ASF), and how to defend against them.

As the world scrambles to address important diseases like COVID, it's African swine fever (ASF) that's turning up the heat on the hog sector. 

A serious viral disease of pigs that can cause fever, internal bleeding and high death rates, ASF is extremely contagious, spreading rapidly through both direct and indirect contact with infected pigs or pig products. 

Though there is a concerted effort to keep it out of Canada, such was the case with COVID-19, and we know how that turned out. In helping industry prepare for a worst case scenario, Dr. Aruna Ambagala presented a talk on “Diagnosis of ASF using Alternative Sample Types” as part of SIP’s webinar “African Swine Fever: How is Canada Getting Prepared?” at the 2021 Banff Pork Seminar.

With any virus, diagnosis is critical, and that is doubly true with a disease like ASF that can be hard to spot on farm. Though Canada has cutting edge diagnostic tools, the danger from the virus, and the ambiguous clinical signs that often accompany it, have scientists focused on continuous improvement.

“We have two options when it comes to ASF diagnosis,” said Dr. Aruna Ambagala, a research scientist with the Canadian Food Inspection Agency (CFIA) at the National Centre for Foreign Animal Disease (NCFAD) in Winnipeg. Dr. Ambagala is head of the Mammalian Disease Unit and World Organisation for Animal Health (OIE) Reference Lab for Classical Swine Fever at the NCFAD. “We can either look at the virus itself, or at the antibodies to the virus.”

When looking for the genomic material of ASF virus, scientists use a real-time PCR screening test available at the NCFAD and at labs that are part of the Canadian Animal Health Surveillance Network (CAHSN). The CAHSN is a network of federal, provincial, and university animal health laboratories across Canada.

Testing Time

The PCR test, which requires two to four hours to complete and review, can be employed in ongoing outbreaks to detect ASF in pigs. Following this test, additional tests will be performed at the NCFAD to confirm the results.

“If a pig is dead, we request a full post-mortem and submit tissue samples such as tonsils, spleen, liver, kidney or lung,” said Dr. Ambagala. “The most important sample for detection of ASF and other viruses like classical swine fever are the tonsils, and bone marrow is requested if the carcass is decomposed.”

For the antibody option, which is used to find evidence of past virus exposure, an ELISA based test is carried out to spot the antibodies in serum samples months or years after infection. ELISA (enzyme-linked immunosorbent assay) is an immunological assay commonly used to measure antibodies, antigens, proteins and glycoproteins in biological samples.

Given some limitations to the ELISA based test, additional tests using whole blood or serum samples must be done to confirm the results.

Surveillance based on individual animal sampling can come at considerable expense and increased labour requirements, as each pig must be handled separately, or a full post-mortem completed. In an attempt to ease that burden, researchers on this project examined alternative sample types for live groups of animals and herds with high mortality.

“For group samples, we are looking at oral fluids and processing fluids. In the case of samples from carcasses, we need ones that can be collected quickly and safely from dead pigs without a full post-mortem, such as lymph nodes accessible through the skin, skin biopsies, ear notches, ears and meat swabs.”

The facts on fluids 

As a mode of sampling, oral fluids have several advantages. They are a rich sample that is easy to collect, as producers can simply hang a rope from the ceiling and wait for pigs to chew on it.

Oral fluids have proven effective for detection of PRRSV [Porcine reproductive and respiratory syndrome virus], PCV2 [Porcine circovirus type 2] and SIV [Swine influenza virus]. Last, but certainly not least, they can be collected in a manner that is humane and non-invasive.

Of course, testing with oral fluids needs to be validated for accuracy before it can be widely used. To that end, the NCFAD is assessing the effectiveness of these fluids for early ASF detection in a project with the Plum Island Animal Disease Center of New York.

“We inoculated four pigs in a pen with ASF and found we could identify the oral fluid before the animals showed real clinical signs. We then repeated that experiment on a larger scale with similar results.”

Since more validation is always better in scientific circles, field evaluations are planned for Vietnam, as well as more lab testing here at home. “We are also looking in more detail at the diagnostic sensitivity, specificity and measurement of uncertainty of the oral fluid samples. We are trying different instrumentation and technicians, and, because these samples can be tricky to work with, we are planning to conduct a reproducibility experiment where we test the same oral fluid samples at two labs to ensure our detection is accurate.”

Science is all about collaboration, and this project is no exception. Working to enhance the effectiveness of ASF detection in oral fluids, Dr. Ambagala and colleagues are teaming up with Iowa State University. They also want to gauge the effectiveness of commercial PCR kits to spot ASF in oral fluids, and will partner with Kansas State University to drive that effort.

The other option being considered for ASF detection is processing fluid, which is collected during castration and tail docking. “With processing fluids, we are targeting breeding herds and suckling pigs, two groups that are not well suited to oral fluid testing because they won’t go after the rope that is used to collect the fluids. 

If we can target these groups with this sample type, we will expand our ability to screen our swine herds, and to do so with much less strain on producer finances and human resources.”

To offer veterinarians a third choice to replace complicated post-mortem sampling, scientists are investigating alternative sample types. Research continues on practical, affordable ways to diagnose ASF, but until there is a viable vaccine, alternative sample types may be our best shot.

Also called DON, vomitoxin is produced by Fusarium fungi that cause fusarium head blight in corn, wheat and barley. 

Vomitoxin can be toxic when inhaled, absorbed through the skin, or consumed at very low concentration levels, so that even small amounts may be harmful to humans and animals.

In pigs, vomitoxin at levels above 1 ppm (parts per million) may cause a reduction in feed intake and growth rate. These effects become even more pronounced at higher concentrations, leading to significant losses for producers. In response, researchers sought strategies for detoxifying vomitoxin using innovative chemical and biological approaches in post-weaning piglets.

For this project, the starting point was sodium metabisulfite (SMBS), an inorganic compound used as a disinfectant, antioxidant and preservative agent with certain food. Scientists already know that this compound can transform vomitoxin in vitro and reduce its toxicity, but what about adding it directly to the feed so it detoxifies DON in the piglet’s gut?

Water worries

One challenge with this approach is that SMBS is highly sensitive to moisture. When exposed to water in the body, it decomposes quickly to produce gas that upsets the stomach. As a means of protecting SMBS, researchers used different fats to create technologies that encapsulate the compound and produce microparticles that can be mixed with feed for consumption by the animals.

Based on their trial results, scientists may have solved the DON dilemma. To gauge how effectively SMBS neutralizes the impact of vomitoxin, they combined the chemical with DON-contaminated feed, fed it to post weaning piglets and monitored the results. Whereas such feed normally impairs or halts pig growth, the coated SMBS managed to reverse the negative effects on growth performance.

Protecting health and wealth

The results mean that the research team has proven the viability of their concept, that it is feasible to use encapsulation technology for effectively delivering SMBS as a detoxifying agent for swine production. This is an encouraging sign for producers and the industry, as vomitoxin is both a financial burden and a safety hazard.

Once the toxin is detected in pork, producers may be banned from exporting their products to other nations, depending on the concentration. While each country has its own limits, they are generally 1 ppm or less, and nowhere is the havoc wreaked by mycotoxins on Canadian pork sales more evident than in Japan. The country is our second largest export market, purchasing 264,635 tonnes of pork worth $1.3 billion in 2018. It is also one of the strictest nations on earth when it comes to mycotoxins, rejecting any food products with levels above 10 ppb (parts per billion). Consequently, anything that protects our pork will safeguard the bottom line for producers.

A coast to coast approach

A project that is addressing a worldwide issue and forging new technology is a huge undertaking with a lot of moving parts, and this study was no exception. Backed by funding from Swine Innovation Porc (SIP), Ontario Pork and Agriculture & Agri-Food Canada (AAFC), the research team was comprised of members from across the country and spanned universities, government and research facilities.

AAFC in Guelph was well represented with research scientists Dr. Joshua Gong and Dr. Qi Wang, as well as Dr. Dion Lepp, biologist and manager of the Guelph Research and Development Centre’s genomics lab.

Participating from Quebec was Dr. Martin Mondor, research scientist with the Saint-Hyacinthe Research and Development Centre.

Out west, the University of Manitoba’s (U of M) Faculty of Agricultural and Food Sciences provided a number of collaborators: Dr. Chengbo Yang, associate professor, Department of Animal Science; and Dr. Song Liu, professor, Department of Biosystems Engineering.

While pleased with their progress thus far, the team plans to seek more funding to continue their research and examine how their findings hold up in a barn setting. While they can’t stop vomitoxin from sounding bad, they hope to make it a bit less scary in the years ahead.

When it comes to feeding your animals, forget about nice linens and gourmet meals. 

To support their growth and well-being, pigs need good, nutritious food on a regular basis. The challenge for producers is to offer those meals without breaking the bank. Given ever rising feed costs and the volume required on farm, especially for growing-finishing pigs, scientists investigated new options to diversify the ingredient supply and methods for getting the most from nutrients in pig diets.

Today, a burgeoning global population and rapidly evolving climate change have altered the food producing environment. More than ever, alternative ingredients, especially proteins and fats, are required to sustain the pork sector, the food chain and the planet. To give producers the greatest return on their feed investment, those ingredients must be of high quality and able to maximize pig performance.

A healthy pulse

With those ends in mind, researchers focused on a few key areas in these studies. First, they looked to characterize the nutrient content of Canadian grown pulses, which have gained attention as alternatives for inclusion in current swine diets. These pulses included two varieties of field peas, as well as lentils, chickpeas and faba beans. They also aimed to understand how pelleting and extrusion under different conditions affect the nutrient content of the ingredients.

Pelleting is the process of converting finely ground mash feed into dense, free flowing pellets. Pelleting a diet makes it easier to handle feed and helps reduce feed waste, while supporting optimal performance. Research has demonstrated that pelleted feed supports roughly a 7% increase in feed efficiency.

Extrusion, which involves applying heat, moisture, and pressure to an ingredient, can improve energy and protein digestibility for pigs, and the heat treatment increases the storage life of pulses by reducing water content.

Amino acids to the rescue

The project also measured the digestibility of amino acids in faba beans, lentils and yellow field peas. Since pigs are unable to synthesize all of the amino acids required to function normally, they must obtain many of them from feed ingredients.

Based on their work, researchers now have sufficient nutrient data on Canadian grown field peas, lentils, chickpeas and faba beans for these ingredients to be considered for inclusion in swine diets.

Dare to be different

While pulses are rich in macro and micronutrients, the study noted that various cultivars differ in what they can provide and how they react to processing treatments. Overall, however, there were no extreme detrimental effects of processing on nutrient content of the pulses, specifically in relation to protein and amino acid content.

For swine nutritionists, the results also warned against making assumptions on how the nutrients of one pulse ingredient might change due to processing, simply by comparing it to another pulse ingredient.

As for pork producers, they will now have more quality, low-cost feed options. Additionally, they can consider different processes, such as extrusion, to improve the digestibility and availability of nutrients.

Teams work

Three people led the way on this project:  Dr. Kate Shoveller, professor, Animal Biosciences at the University of Guelph (U of G); Dr. Dan Columbus, research scientist – nutrition at the Prairie Swine Centre (PSC) in Saskatoon and adjunct professor in the Department of Animal and Poultry Science at the University of Saskatchewan (U of S); and Cara Cargo-Froom, a PhD student at the time and currently a postdoctoral research fellow at the U of G.

Other key experts involved were Dr. Rex Newkirk, associate professor in the Department of Animal and Poultry Science at the U of S; Dr. Yongfeng Ai, associate professor, Food and Bioproduct Sciences, U of S; Dr. Olufemi Babatunde, postdoctoral researcher- Nutritional Physiology at the PSC; and Dr. Chris Marinangeli, former Director of Nutrition, Science & Regulatory Affairs with Pulse Canada and currently Senior Director, Research and Regulatory Affairs at Pulse Canada

Although scientists can now draw broad generalizations about changes in nutrients across pulses or within a pulse category (e.g., changes in beans), there is more to be done. Understanding how processing can affect each category of pulse, and the varieties within the category, can provide much needed insight on the specific varieties of interest.

As part of her ongoing program, Dr. Shoveller will continue to seek quality protein sources for pigs, dogs, cats and horses.

With the high price of pig feed these days, anything that lowers your cost is easy to swallow. 

Science is constantly seeking new ways to do that, and a recent study found that pulses, especially faba bean, could help trim the expense.

Pulse power

In a bid to diversify energy and protein for pig diets, University of Alberta researchers have been looking at increasing the inclusion of locally grown pulses in feed. Apart from reducing feed cost, there are a number of agronomic and sustainability benefits to growing pulses. In addition to fixing atmospheric nitrogen (N) in symbiosis with root bacteria, pulses aid in diversifying soil microbial populations and nutrient uptake. If that’s not enough, they also break pest and disease cycles in yearly crop rotation with cereal grains and oilseeds.

This study looked at the potential for faba beans, which offer greater yield compared to field peas, fewer inputs in relation to other crops, and a lower carbon footprint than sourcing animal forms of protein.

However, the inclusion of faba beans in swine diets has been limited by its content of antinutritional factors like tannins and vicine and covicine. Antinutritional factors are components in food that can reduce nutrient use or feed intake. In response, researchers have found solutions through this study by identifying more suitable faba bean cultivars for producers.

Faba takes flight

When faba beans were first introduced to Western Canada about 20 years ago, their high tannin content served as a double-edged sword. The tannins helped guard the crop from early frost damage in the fall, but they gave the beans a bitter taste, rendering them of limited value for inclusion in pig diets. To improve their feed potential, a new white-flowered cultivar named Snowbird was introduced. While its lower tannin level improved feed potential, that came at the expense of reduced protection against early frost.

In a nutshell (or bean pod), the dilemma was this: How could science achieve the best of both worlds for producers, rendering the beans effective as a crop and a feed source? For a solution, crop researchers have reduced the level of tannin to retain frost protection while enhancing digestibility of the bean. Though producers also receive low tannin levels with Snowbird, they lose frost protection in the process. In the course of this study, University of Alberta researchers found that faba bean cultivars with moderate amounts of tannin could still be included in pig diets, provided that the cultivar was also low in vicine and covicine – the anti-nutritional factors. This was a notable breakthrough for producers, as it meant they could reduce their risk of frost damage while growing faba bean for both food and feed without harmful effects.

 It pays to be picky

To maximize the benefit of adding faba beans to a rotation, it’s important to do your homework before choosing the best variety for your farm. Among faba bean cultivars with moderate tannin content, researchers found Fabelle to be a top choice for feed intake and weight gain. Across cultivars, variations in dietary fiber and starch content contribute to differences in dry matter, energy digestibility and growth performance of pigs – which can all impact the bottom line. On the other hand, while ensuring that a cultivar will benefit your pigs is obviously paramount, this also needs to be weighed against yield impacts from reduced frost protection.

Having established the viability of faba beans in reducing feed cost, scientists on this study feel that getting that message to the end user is critical. For the findings to be adopted, pig producers must be convinced that pulse grains like faba bean are cost effective.  By replacing expensive soybean meal with the less costly faba bean as a protein source, while maintaining growth performance, producers can reduce feed cost per unit of growth.

Digesting the results

Though researchers found that the antinutritional factors in faba beans may slightly reduce a pig’s ability to digest nutrients, this should not hamper growth if producers consider that fact when formulating diets. For feeding pigs, medium levels of tannins in faba bean are acceptable, provided that vicine and covicine levels are limited.

This study was led by Dr. Eduardo Beltranena, pork research scientist at the University of Alberta. In the barn and lab, graduate student Protus Nyende did the legwork, ensuring that all trials were completed accurately. The project was supported with funding from Swine Innovation Porc and Alberta Pork, which was provided to Dr. Ruurd Zijlstra.

As its next order of business, the team plans to delve deeper into characterizing faba bean cultivars and gaining a better picture of what is happening with this ingredient in western Canada. Wherever that may take them, they know their work to date should take a bite out of producer costs.

Now THAT’S food for thought.

To a non-scientist, the notion of “good bacteria” is like the idea of a friendly monster - it seems counterintuitive or even contradictory at first glance. 

In fact, the bodies of pigs and people contain more helpful bacteria than the bad kind, especially in the gut. Since good bacteria, also known as probiotics, play a critical role in keeping pigs healthy and producers above water, researchers ran a study to better understand both types of bacteria.

Probiotics offer a number of benefits for pigs, such as improved digestion, protection from pathogens and the production of nutrients and antibodies. These advantages are especially valuable for peri- and post-weaning pigs, as they are often exposed to diseases like E. coli and rotovirus, a highly contagious infection that causes diarrhea and dehydration. At present, the main means of combating these conditions on farm are vaccination, zinc supplements and the inclusion of antimicrobials in feed; but all three have limitations.

Good news, meet bad news

For their part, antimicrobials have sparked a public health concern as more and more infections show resistance to these drugs. They also represent another cost to producers and could render future pathogens harder to treat.

While vaccination has its place in the barn, it is less effective with younger pigs, as their immune system is not yet properly developed to respond to vaccines.

As for zinc, its negative impact on the environment has been well documented, leading some countries to ban its use with pigs, and Canada may soon follow suit. In the eyes of scientists on this project, the best alternative to these measures are probiotics. Previous research has shown that piglets who are not exposed to good bacteria early on can be highly susceptible to disease. With the addition of probiotics to swine diets, like Lactobacillus that is also found in yogurt, the influx of good bacteria in the gut works to crowd out the bad ones. Lactobacillus is a probiotic that restores the balance of good bacteria in the intestine that may be disrupted after the application of antibiotics or due to intestinal infections.

A gutsy effort

In their quest to learn more about bacteria as it relates to pig health, scientists explored the composition of the gut microbiota, which comprises thousands of bacteria. One finding of interest is that the microbiota changes as pigs age. At birth, piglets have no bacteria in the gut, but begin to acquire them when exposed to the sow during farrowing. Because the bacteria needed to digest liquids and solids are different, the microbiota changes again when piglets move from a liquid milk diet to solid food after weaning.

Researchers also examined the relationship between the gut microbiota and growth performance, and found that pigs of a certain microbiota enterotype showed better growth and less incidence of diarrhea. An enterotype is a classification of living organisms based on the bacterial composition of the gut’s microbiome.

Finally, the team sought a connection linking the microbiota and genetics, noting that some bacteria is unable to survive in the pig’s gut due to a genetic variation in the animal.

Knowledge is powerful

When it comes to pigs, health and bacteria, the more science knows, the more it can aid producers. With antimicrobials being slowly phased out, industry needs an alternative to keep pigs thriving in the face of a disease challenge, and probiotics show the best potential. Many pharmaceutical companies have expressed interest in developing probiotics. To support these efforts, science must gather as much knowledge as possible, such as how to distinguish good and bad bacteria in the gut.

If the work from this study leads to a new probiotic that can be commercialized and used by producers, it could amount to a triple threat: healthier pigs, a more productive swine industry, and less reliance on antimicrobial use in animals.  

To ensure success for researchers, collaboration was critical. They received funding from Swine Innovation Porc (SIP), Cargill Limited, and the Ontario Ministry of Agriculture, Food and Rural Affairs (OMAFRA).

The research team included Dr. Vahab Farzan, Dr. Brandon Lillie, Dr. Khurram Nadeem, and graduate student Madison Arsenal from University of Guelph, as well as Dr. Ehsan Khafipour from Cargill Inc.

In the years ahead, scientists envision a time when they pinpoint the specific bacteria that are associated with better performance and health, and use them to produce effective probiotics for pigs. If they can also identify the genetic markers for these traits, that information could be shared with swine breeding farms for the betterment of their herds.

In a sector where things aren’t always cut and dried, there is at least one certainty: Piglets need milk, and an adequate supply is crucial for their development. 

Unfortunately, sows don’t produce sufficient milk to optimize piglet growth. As well, the introduction of hyperprolific sow lines (ones that often give birth to more piglets than their functional teats) has made the problem greater by increasing litter size. As a result, there is less milk available per piglet, leading to lower weaning weights.

With sufficient milk in their system, piglets will be heavier at weaning, have greater vigor and be more resistant to disease challenges. They will also require fewer days to reach market weight, something producers currently address with creep feeding (providing a solid diet to piglets while they are suckling the sow, preparing their digestive system for weaning). Though creep feeding can be effective, it is also expensive, so science went in search of a more viable option.

Got Milk?

Taking up the challenge was Dr. Chantal Farmer, research scientist with Agriculture and Agri-Food Canada in Sherbrooke, Quebec. To address the milk shortage, Dr. Farmer sought to increase milk yield through enhanced mammary development, taking a multi-pronged approach:

Feeding fiber

With gilts growing faster these days, they often encounter leg issues, prompting some producers to slow that growth by restricting feed intake. This can be problematic, as Dr. Farmer had previously shown that a feed reduction of 20% between day 90 and puberty inhibits mammary development. With that in mind, she teamed up with Dr. Lee-Anne Huber at the University of Guelph. 

They found that either using that same 20% decrease in feed intake or feeding an ad libitum diet (as much as the pig wants) with 25% more fiber could have a similar effect. Both approaches will reduce the growth rate of current gilt lines (that consume more feed compared with older lines) without lowering milk yield.

Need lysine? Try soybean

In the last third of gestation, mammary development is very rapid; however, there seems to be an underestimate of the recommendation for the dietary amino acid lysine during that crucial time. 

By putting more soybean meal in feed, researchers managed to boost lysine levels by 40%, which increased the amount of milk synthesizing tissue in the mammary gland by 40% as well. Like farmers, scientists can’t stand still, so they will look to further benefit producers down the road by testing the lysine effect on multi-parity sows as well.

Prolactin is pro-milk

Prolactin is a hormone that plays a critical role in enabling mammals to produce milk. In the past, the hormone has been injected to raise prolactin levels in sows and increase milk yield. Through this study, researchers examined the potential for a drug called domperidone. This drug helps the body increase its own production of prolactin, and is even used by women who can’t supply enough breast milk after giving birth. With a veterinary prescription for use with sows, domperidone can be added to feed to stimulate prolactin, replacing the need for hormone injections. Given the current scrutiny around added hormones for animals, this could mean a better image for the industry as a whole.

As well, when the project team tested the drug that aids pigs in synthesizing more prolactin, they saw an average increase of 5.6% in body weight for piglets at day 22.

As with much in life, timing is critical for increasing prolactin. Prior to puberty, the gilt’s physiology is not equipped to reap the benefits from the drug; for best results, it needs to be incorporated in the diet during lactation.

Though all aspects of the study hold promise, the raising of recommended lysine levels in the gestation diet may be most critical. At present, some in the industry still assume that replacement gilts can be fed like market pigs, and that is simply not the case.

Hungry for More

Ultimately, this study was the product of cooperation. While Dr. Farmer provided expertise in swine lactation biology, Dr. Huber brought her extensive knowledge of swine nutrition. Work was done at both the University of Guelph and Universite De Sherbrooke, providing opportunities for new graduate students at these institutions.

Building on this study, researchers want to answer a key question related to the beneficial effect of an increase in soybean meal on mammary development of gilts in late gestation: Is that benefit really due to the increase in lysine, or to other components of the soybean meal?

With the high cost of production these days, anything that stimulates the mammary system should be a stimulating topic for years to come.