The use of horse meat in foods for human and pet consumption is frowned upon in the United States, Rena. As a result, almost all horses slaughtered in the U.S. are shipped overseas for consumption, which decreases the chance of horse meat being included in products manufactured here. However, if you’re curious about a product's ingredients, the best thing to do is thoroughly check the label. The FDA requires that all ingredients be listed on pet food labels. Foods that list "meat by-product meal,” as one of their ingredients can contain any number of meats, so you may want to watch for that and instead, choose foods that include "chicken by-product meal,” or are more specific with their list of ingredients.