Integrated Approaches to Replace Antimicrobials and Promote Health in Weaned Piglets.

Why is this project important?

Weaning is a critical and difficult time for piglets, as they are undergoing several stressful changes including separation from the mother, a change from milk to solid feed and a new housing environment. Compounding the problem is that during this period, their digestive and immune systems are far from fully developed. As a result, piglets often suffer from decreased feed intake, impaired digestion, and an increased susceptibility to disease.

During this period, enterotoxigenic Escherichia coli (ETEC) – a leading cause of bacterial diarrheal illness - often causes colibacillosis, a common disease of nursing and weanling pigs caused by colonization of the small intestine by strains of ETEC. Colibacillosis typically results in severe, watery diarrhea and dehydration. Weaning can also be marked by Streptococcus suis (S. suis), an infection that may lead to arthritis, septicemia, and meningitis with sudden death in piglets.

While the pork sector has used antibiotics for decades for these infections, over reliance on this approach has led to anti-microbial resistance. Consequently, the European Union (EU) has banned antibiotic growth promoters (AGP) in animal food production since 2006, while Canada did the same beginning in 2018. Unfortunately, the removal of antibiotics can compromise piglet gut health and growth performance. Since no single option can replace antibiotics completely, researchers on this project are seeking an integrated approach to protect the animals. This strategy would combine two bacteriophages – one for E. coli and one for S. suis – and functional amino acids such as tryptophan to safeguard piglet health. A bacteriophage is a virus that neutralizes a bacterium by infecting it and reproducing inside it.

What will researchers do?

Researchers will focus on four key activities for this project:

1. Assessing the feasibility of bacteriophages in the management of post-weaning diarrhea (PWD) associated with enterotoxigenic E. coli (ETEC) in pigs. 

   
   
   
   

2. Isolating S. suis phages and evaluating their capacity to protect pigs against S. suis infection.

   
   
   
   

3. Evaluating and optimizing the use of functional amino acids to improve gut health and performance of weaned pigs.
   

4. Developing combinations of bacteriophages, probiotics, and functional amino acids and determining their effectiveness in improving performance and health in weaned piglets.

What will be the benefit of this research?

While Canada has made substantial progress on the use of antimicrobials in livestock production, there is still significant room for improvement. The pork sector must continue to develop effective strategies to improve the health status of pigs while reducing or eliminating their reliance on antimicrobials.

Finding alternatives to antibiotics will benefit pigs, producers, and consumers. For the animals, it will prevent the negative effects of removing these drugs from their system, including increased mortality, reduced growth performance and lower feed use.

Of note, given the current negative view of antibiotic usage in animal production among consumers, identifying a substitute will help allay their concerns and increase public trust in the pork industry. Finally, this project will improve science’s understanding of the molecular mechanisms underlying the functions of the new alternatives. This will enable researchers to make the best use of them for promoting pig health and production going forward.

What has been done so far?

Researchers have conducted a literature review in preparation for the study and have recruited students to assist with the project.

Project status: Currently in progress. Results expected in 2028.

Collaborators:

• Dan Columbus, Prairie Swine Centre

• Qi Wang, AAFC-Guelph

• Joshua Gong, AAFC-Guelph

• Hany Anany, AAFC-Guelph

• Vahab Farzan, U. of Guelph

• Robert Friendship, U. of Guelph

• Brandon Lillie, U. of Guelph

• Nicole Ricker, U. of Guelph

• Cezar Khurisgara, U. of Guelph

• Martin Nyachoti, U. of Manitoba

• Song Liu, U of Manitoba

• Karmin O, U. of Manitoba

• Benjamin Willing, U. of Alberta

• John Fairbrother, U. of Montréal

• Dongyan Niu, U. of Calgary