Dr. Joshua Gong

Dr. Gong is a Researcher Scientist with Agriculture and Agri-Food Canada (AAFC), based in Guelph. He has been in that role and working with poultry since 1999. Gong received his M.Sc. degree from the China Agricultural University and PhD degree in microbiology from the University of Guelph in 1994.

The Canadian Poultry Research Council (CPRC) has supported a number of projects from Gong’s research team who have done a great deal of work on priority issues for the poultry industry. Gong has also been a valuable collaborator with CPRC since its inception, providing consultation advice during the forming of the council and serving on the scientific advisory committee to evaluate research proposals submitted to CPRC. He was also the first Lead of AviMicroNet (Canadian research network for avian microbiology) under CPRC. To-date Gong has co-authored more than 125 research and review articles, 3 patents, and over 190 conference abstracts.

Fostering expertise in the industry

Gong has co-supervised 15 Ph.D., 3 MSc, and 17 project students and hosted nearly 20 visiting scientists and post-doctoral fellows. Among his former students and post-docs, three are continuing to conduct poultry research as a professor or professional in research institutions in North America. Another two are with the industry relating to poultry located in Guelph- one is now a Scientist at Elanco Canada, and the other is a Scientist at Ceva Animal Health Inc.

Highlights of research outcomes

The very first project funded by CPRC was a collaboration of Dr. Gong and Dr. Shayan Sharif (University of Guelph) who continue to work together today. This particular study was among the early research investigating how antibiotics change the gut microflora in broiler chickens and how those microbial changes can affect chicken immune response. Using DNA techniques, they identified microflora composition changes in the chicken gut responding to antibiotics in feed. Additionally they found that Virginamycin and Bacitracin (two commonly used antibiotics in poultry) both had an effect on Lactobacillus bacteria in the gut- some lactobacilli would increase or decrease in number in response to exposure to the antibiotics, and the net result could alter chicken immune response. The knowledge gained from this study led to the later work by both research groups on developing effective probiotics.

CPRC initiated the first Poultry Cluster in 2010, which has brought together scientists from various fields to work on priority issues for the industry. As part of the first Cluster, Gong’s group aimed for developing technologies to encapsulate essential oils (volatile components of plant extract) for effective protection and delivery to the chicken gut. Essential oils have previously shown strong antimicrobial activity against enteric pathogens including Clostridium perfringens (a pathogen causing necrotic enteritis in poultry), therefore demonstrating potential as an antibiotic alternative. The research led by Dr. Gong has demonstrated the effectiveness of encapsulated essential oil in combating C. perfringens to control necrotic enteritis (NE). Gong’s group has continued this work over the years and in 2014 Chicken Farmers of Canada approved funding for his team to validate encapsulated essential oils in on-farm trials for controlling NE disease in commercial broiler production.

NE is among the most common enteric (intestinal) diseases in poultry caused by C. perfringens that adheres to and damages gut tissues. Left unchecked, this damage can impair nutrient absorption, reduce growth performance and, in severe cases, cause mortality. As part of the second Poultry Cluster, Gong’s team, in collaboration with Dr. John Prescott (University of Guelph), investigated the potential in developing a novel vaccine for controlling NE, for which an effective method has yet to be developed. Pilli (hair-like cell surface appendages, often important in pathogenesis) have often been used to develop effective vaccines for controlling a number of human and animal infections, and the team has identified a specific pilus with good potential for developing a vaccine to control NE. Trials for the vaccine development are still underway.

Another project of Gong’s in the second Poultry Cluster investigated the potential of butyrate glycerides as an alternative to dietary antibiotics to enhance chicken growth performance. Dietary supplementation of butyrate has been reported to improve growth performance of broilers. Butyrate has also shown antimicrobial activity. However, the application of pure butyrate is limited by its offensive smell, difficulty to handle, and its absorption in the upper gut. In contrast, butyrate glycerides have no such issues, are water soluble, and can release butyrate in the small intestine, thus providing a novel delivery system to the chicken gut. Trials done by Gong’s research team demonstrated that butyrate glycerides can benefit broiler production by reducing abdominal fat and increasing breast muscle, although no impact on overall growth and feeding efficiency of broilers was observed. Additionally, they found that the effects of butyrate glyceride supplementation can be significantly different on genetically similar birds, so outcomes on a given flock may be variable.

Next steps

Gong is continuing work on the encapsulated essential oils. He and his colleagues at AAFC are now collaborating with a feed company and a consultant to conduct on-farm trials. This would be one of the last steps in the validation process, with the hope of getting the product on the market for farmers’ use.

Work is also continuing, not only by Gong’s team but by researchers worldwide, on a vaccine for controlling necrotic enteritis.