Mr. Chair, I wish I had a simple answer to that question.
The introduction of disease and the spread of disease on a farm or premises where animals are kept are very complicated and complex. There are a number of ways a disease can enter into a farm. Humans can introduce disease onto a farm. Animals can introduce disease onto a farm, and that includes animals that may have left the premises, commingled someplace else and come back. It can also be the introduction of new animals.
We also have wildlife that have the potential to introduce disease onto farms. In cases of highly pathogenic avian influenza, we have seen that wild migratory water birds are the likely source of introduction into Canada. We also have things that can introduce disease—tractors and objects that might be contaminated with manure from wild birds, for example. That is why biosecurity contemplates all the different routes of transmission onto premises.
We also have to think about which disease we're worried about. How is it transmitted? Is it a virus? Is it bacteria? Is it food-borne, feed-borne or water-borne? That is why biosecurity standards and protocols are so important. Each farm is going to have different risk factors to consider, and those national biosecurity standards give people a starting place from which to build their own.
I would also say that we are not aware of a confirmed case of a disease as a result of trespassers, but humans are a factor in the introduction of disease onto a farm.
To conclude, Mr. Chair, I would like to say that we as the Government of Canada take the health and well-being of animals, including farmed animals, very seriously. The vast majority of producers also take the health and welfare of their animals very seriously. It is linked to their livelihood and their businesses.