Would there be a Kosher concern of animals being fed non-Kosher (animal) feed?
The Halachic answer is: In most instances, what animals eat have no effect on their Kosher status. The news about Kosher poultry is somewhat more heartening. The largest provider of Kosher poultry, Empire Poultry Co. makes the claim on their website they their poultry is ‘free-range, and their care does not allow hormone or antibiotics and certainly no animal wastes. A number of other small companies raising chickens serving the Kosher market make the same claim. On December 29, 2003 the OU issued the following statement about BSE. FOR IMMEDIATE RELEASE CONSUMER MAY HAVE ADVANTAGE IN PURCHASE OF KOSHER BEEF, ORTHODOX UNION EXPERTS ANNOUNCE, AS KOSHER SLAUGHTERED CATTLE HAVE BEEN FREE OF MAD COW DISEASE “To this date, no kosher slaughtered cattle anywhere in the world have ever been found to have had mad cow disease,” Rabbi Menachem Genack, Rabbinic Administrator of the Kashrut (Kosher) Division of the Orthodox Union, and Rabbi Yehuda Kravitz, the Division’s specialist in meat slaughter