Hello, recently I bought 2 large pack of dog food and found there's maggots in it. I tried removing the maggots but there are just too many of them. In the end, I decided to throw all of them away.

It was really a hard decision because i feel cheated for my money and I did'nt want to affect my dogs.

I just want to know how can the maggots develops inside the dog food and how to ensure we buy a pest-free dog food?