A very plausible possibility in Canada I know that they waived all plant and ingredient inspections as well as safety measures regarding any vaccines related to COVId-19, under the ACCESS agreement.Or they could just have bad quality control, and some of them end up contaminated by all kinds of things.
The only issue that I have is that 5% is an awful neat number, and one could hypothetically propose that was done to cull the herd at a rate that would not overly spook the herd. Again just a hypothesis nothing to validate.