The easiest and most practical way to keep ants from invading pet food is to store them in pet food containers. Use air-tight pet food tins or dog treat jars to keep your pet food stock fresh, and then use a smaller dog food storage container for your dog's left over treats. This will work well to keep the leftover food fresh and ant-free, so you can re-serve when your pet gets hungry.


Here are a few tips for getting rid of ants in left-over dry pat food:

1. If you have neglected to transfer the leftover food to a sealed container and ants have already invaded, just cover the dish and then put it in the freezer. Keep it there for two hours or more - this will kill the ants without ruining the food.  
2. While the food is in the freezer, go back to the feeding area and try to sweep off any crumbs or morsels that may have spilled on the floor. Wash the area with soapy water to keep ants from returning.  
3. After 2 hours, take the food from the freezer and put in a strainer. Shake vigorously over the sink until there are no more dead ants coming out. Put in a dog plate and re-serve.


As for ants in pet food bags:

1. If the bag is relatively small, just transfer food into a small container and freeze the food.
2. If the bag is quite big, empty its contents into a plastic bucket or any other type of water-safe container. Leave it uncovered.
3. Next, fill a tub or sink with three to five inches of water, set the container of ant-infested container on it, and stir the food. This will get the ants out of the container, and then they will eventually drown.  
4. This will take about three or more days to get rid of all the ants. Once the food is cleared of ants, transfer them onto large dog treat jars.