They do have some pretty weird rules though.
15 Feb 1964 Watchtower, Questions From Readers
What, then, of animal food? May it be used if there is reason to believe there is blood in it? As far as a Christian is concerned, the answer is No, on the basis of principles already mentioned. Therefore, if a Christian discovers that blood components are listed on the label of a container of dog food or some other animal food, he could not conscientiously feed that product to any animal over which he has jurisdiction. He could not conclude that doing so would be excusable, for this would not be a case of an animal killing another animal and helping itself to the blood of that creature. No, this would be a direct act on the part of the Christian, making him responsible for feeding blood to a pet or other animal belonging to him.