Using rat repellent is dangerous for raptors. The hawks catch the sick rodents, eat them and the poison, and are themselves poisoned. Not to mention your dogs will get poisoned if they eat the poisoned rodents. Use a Ratinator rat trap. It comes with a plastic box that you put the trap in with the rats and fill with water. Safely drowns them.
Also get lots of cats. Don't neuter them because the kittens will themselves become coyote and owl food. Sounds mean, but it is nature's way.
We use the large metal 50 gallon drums for feed, and 30 gallon trash cans. Rodents will chew thrugh the bottom of the plastic trash cans. DH bought some of the heavy duty plastic dog feed containers (expensive) and the rats chewed right thrugh the bottoms and sides! If yu get the 50 gaon barrels, make lids with large circles of plywood. Screw handles on the to and then attach pieces of wood under the bottom of the plywood to fit inside the barrels. Those pieces of wood will keep the lids in place. Whie you may get some bugs in the barrels the rodents are the most dangerous since rats will pee and poop on a food source after they have eaten their fill. Other animals will not touch rat peed and pooped on food, so your entire barrel then has to be dumped. Rat feces also carries disease that you can catch when handling the food. Make sure that the barrels are stored in a dry place under cover so the feed doesn't get damp and mold.