PIC Update: February 2009

Advances in the genetic selection of commercial laying hens have
reduced the age at onset of lay, improved feed conversion, increased
egg mass, and increased the total number of eggs produced over the
production cycle.

Yeast Beta Glucan and Osteoporosis
The influence of this complex carbohydrate on cage layer fatigue is being studied

Building Bones Researchers are studying the effect of the yeast beta glucan on bone strength and egg production to determine if it can increase calcium in laying hens. Advertisement

Advances in the genetic selection of commercial laying hens have reduced the age at onset of lay, improved feed conversion, increased egg mass, and increased the total number of eggs produced over the production cycle. With this increase in overall egg production, more calcium is needed to produce eggshell. However, as a hen ages, calcium mobilization from the hens bones decreases and less calcium carbonate is produced, creating a calcium deficiency. This deficiency adversely affects egg production and eggshell quality.

Furthermore, laying hens are commonly diagnosed with a disease referred to as “cage layer fatigue,” which is a form of osteoporosis that leads to thoracic vertebrae collapse and paralysis. Osteoporosis results when bone resorbtion (mineral release from bone fluid to blood) exceeds bone formation, leading to bone weakness. Hens with weakened bones result in economic losses for producers, and associated bone breakage raises welfare concerns. For these reasons the industry needs an effective strategy for managing this disease. 

Dr. Bruce Rathgeber and his research team at the Nova Scotia Agricultural College have been investigating the use of yeast beta glucan (a complex carbohydrate) to improve bone strength in laying hens. In lab studies, partially purified beta glucan has been shown to be a potent inhibitor of bone resorbtion. The researchers fed varying levels of yeast beta glucan to laying hens via their feed, and measured both egg and bone parameters.

Their findings? Overall, the yeast beta glucan did have an effect on bone metabolism, but the effect was not great enough to influence bone strength, egg production or shell quality. The amount of yeast beta glucan included in the diet seemed to be a very important factor, and perhaps feeding higher levels than those evaluated in this study would have a greater effect on bone condition and egg quality. To read more, please visit www.poultryindustrycouncil.ca .

Featured Researchers

Dr. Marie Archambault, DMV, MSc, PhD, Dipl ACVM, is currently an assistant professor in the Department of Veterinary Pathology and Microbiology at the Faculty of Veterinary Medicine of the University of Montreal. She received her Doctor of Veterinary Medicine degree from the University of Montreal in 1993. Later, she held various university teaching assistant positions while pursuing her post-graduate education. She obtained an M.Sc. in Veterinary Pathology and Microbiology in 1995, a PhD in Microbiology and Immunology in 2000, and Board Certification from the American College of Veterinary Microbiologists, with a subspeciality in Bacteriology and Mycology, in 2002. From 1999 to 2004, she was the head bacteriologist at the Animal Health Laboratory of the University of Guelph where she was also an adjunct faculty member. In 2006, Dr. Archambault received the best teaching award from the student committee of the Canadian Veterinary Medical Association of the University of Montreal. Her areas of research include antimicrobial resistance and alternatives to antibiotics. Her Natural Sciences and Engineering Research Council of Canada (NSERC) research program is on the investigations into the association between antimicrobial resistance and virulence factors of Clostridium perfringens.

Bacteriophages as an alternative to antibiotics for the control of necrotizing enteritis
by Marie Archambault, University of Montreal

Today’s consumer is becoming more aware of potential drug residues in the products they purchase, and the risk of establishment of antibiotic resistant bacteria in animal and human populations. Developing alternatives to the use of antibiotics in poultry production will help to meet consumer expectations and enhance confidence.

One challenge that has been identified in moving away from the use of antibiotics in poultry production is a rise in the incidence of necrotic enteritis. In countries that are no longer using antibiotics as growth promoters, the incidence of necrotic enteritis has increased markedly. The disease is caused by the bacteria Clostridium perfringens. Infection results in sudden mortality within the flock, with losses of typically around 10 per cent and ranging from about five per cent to 40 per cent.

The use of prebiotics and probiotics has been suggested to help control C. perfringens, but these are not available for practical use in the field at the present time. Therefore, in order to manage this important disease, new methods of prevention must be investigated.

Dr. Marie Archambault and her research team at the University of Montreal have been studying the use of bacteriophages to control C. perfringens. Bacteriophages (phages) are viruses that infect bacteria. If a phage encounters a bacterial cell that is sensitive to it, it will enter the cell and produce more phages, thereby killing the cell and moving to surrounding cells. Because of the mechanism by which phages kill bacterial cells, it is important to identify phages that are as disease specific as possible.

Their findings? The researchers discovered two new phages in poultry litter and poultry digestive tracts. In order to test the effectiveness of the phages on C. perfringens, this bacteria was isolated from the digestive tract of chickens and turkeys at processing plants. Lab testing showed that the newly discovered phages had the ability to destroy a proportion of C. perfringens isolates. The researchers combined these two phages with a third, previously identified phage, creating the first bacteriophage “cocktail” against C. perfringens. Lab work is continuing to optimize the cocktail before testing its effectiveness in live birds.

PIC Picks

It has been relatively quiet at PIC since the conference so I thought I’d tell you a bit about what we’re up to in 2009.

This year we’re looking to see what we can do about ensuring that the research we’re managing on your behalf gets results out in a format that you can utilize more quickly to enable higher productivity. We’ll report on this as the year goes on but first up it’s important to remember that research takes time and it is not one-dimensional.

Productivity is part of the research story, and as a result industry-funded research must seek to improve productivity. But at the same time, the less well-expressed research need of producers (industry) is to be prepared for whatever the climate, disease agents, the community and others throw at us.

To this end PIC has two portfolios of current research, both of which have been derived from the expressed needs of industry through our Strategy. The first is the research that is generated from our annual call for proposals (reported in the November 2008 edition of Canadian Poultry magazine). This is research designed by researchers to address issues we’ve raised in the Strategy.

At first glance, it can seem as though research doesn’t have any relevance to you (like research heavy on scientific exploration such as microbiology, genomics, pathobiology, etc.).  However, in time it can lead to a breakthrough in disease resistance or food safety, and we all benefit.

Then there are the projects that have immediate resonance with producers, projects designed or commissioned by industry. This is a relatively new area for PIC but one that is growing quickly. You may have heard of the work: we’re responsible for looking at the use of GPS to service track vehicular movement on and off properties to reduce the risk of disease transfer in the case of an outbreak (if you want more information – call us). We’ve also commissioned the writing of several service sector biosecurity protocols and we are heavily involved in the procurement and management of personal protective equipment for use in a disease outbreak as part of a cross-industry initiative.

We’ve also just completed three short projects for the Egg Farmers of Ontario looking at the impact in other provinces of their introduction of an animal health act, the upcoming organic regulations and the cleaning and disinfection procedures required in other countries. We’re currently developing three larger projects; one looking at the relative energy values of different poultry manures with a view to recycling for energy production; one looking at poultry barn emissions and how they compare with other livestock and a project that will allow us to scan the literature around the globe on a regular basis to bring the latest innovations from around the world to our industry more efficiently.

Finally we’ve also just completed a review of our local and national research facilities and human resources in readiness to meet with Ontario Ministry of Agriculture, Food, and Rural Affairs and the University of Guelph’s plan for the proposed research facilities at Elora. This year we are going to rework and reissue some of our factsheets on practical management in the barn.

So we have a big year ahead and we look forward to your continuing support and as always if you want more information about what we’re up to at PIC just give us a call or send us an email.

Don’t forget the London Poultry show is taking place at the Western Fairgrounds on April 8-9 our Research Day takes place on May 12.