Health Canada has concerns about environmental and antimicrobial impact of ZnO at high levels in pig diets
By Jackie Clark
Zinc, in the form of zinc oxide (ZnO) is commonly used by pig farmers as a feed additive and is thought to help prevent post-weaning diarrhea.
However, heath professionals are raising concerns about environmental and resistance concerns, which has led to a decision to restrict the use of ZnO in medicated feeds in the EU starting in 2022.
Canadian swine and human health professionals are considering the best way to manage this issue.
“Health Canada has shared with Animal Nutrition Association of Canada (ANAC) that they have environmental safety and co-selection of antimicrobial resistance concerns with the use of ZnO at therapeutic levels in pig feed,” Melissa Dumont, executive director of ANAC, told Farms.com.
“The use of high levels of ZnO in piglet feed to help manage post-weaning diarrhea is considered a therapeutic use in Canada and there is no ZnO product approved for that use in Canada,” she explained. “Therefore, as the modernized feeds regulations are proposing maximum nutrient levels related to animal nutrition, the use of the zinc, whether in the form of ZnO or other, at such high levels is not within the scope of the Canadian Food Inspection Agency’s (CFIA) regulatory authority, rather, it falls under Health Canada’s authority.”
The ANAC is working with the Canadian Pork Council (CPC) to address that concern.
“If Health Canada were to approve a ZnO product to be used at therapeutic levels (i.e. 3,000 ppm maximum, up to 12 kg body weight) in nursery pig diets, then we would be allowed to continue to use it in feed at that level and for that purpose,” Dumont explained. “The use of ZnO for nutritional purposes will continue to be regulated by the CFIA. However, high levels of ZnO used for health/therapeutic purposes could be regulated under Health Canada if the industry is successful in getting a drug product approval for such use.”
As regulations change, farmers may need to work with their swine health team to find solutions.
“Not all farms use ZnO today and there are other management tools available to producers,” Dumont said. “Nutritionists, veterinarians and producers will need to continue to work together to evaluate each farm’s individual needs and come up with that farm’s optimal strategy.”
However, officials don’t expect regulatory changes overnight.
“Any change related to how ZnO will be allowed to be used in Canada will not happen immediately,” Dumont explained. “A phase-out period, similar to the one seen in the EU, will be put in place and we are not expecting any major changes for the use of ZnO in nursery pig diets until 2026. Until then, ANAC and CPC will continue to work collaboratively in identifying options and solutions.”
Swine health and nutrition officials “are keeping a close eye on what is happening in Europe as they transition away from the therapeutic use of ZnO over the next year. We hope to learn from their experience and bring to Canada any lessons learned from their transition,” she added.
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