Banned items for border crossing into Canada

I have crossed the border the other way and have had meat taken one year and found out it was OK the next. That year they were on a dairy products kick....I take next to nothing now and stop at a grocery store once in the US.

My understanding is, if the dog food is in the original package, its OK...could be wrong.
Alcohol is sold at the duty free at the border, so I cant see that being a problem
Guns....Maybe there is a gun shop that would store them near the border