While 20 million sounds like a lot, it is not. I worked in the poultry biz for 30 years and left as a Sr Manager for a very large company.
We slaughtered 6 million each week.
20 million is just a drop in the bucket.
And with the melamine scare being blown out of proportion, you can bet that the U.S. food supply is under tight scrutiny and is as safe as ever.