Https://answers.yahoo.com/question/index?qid=20080317221239AAkXd1K the awnswer is there
Answer: The resolution doesn’t mention the bloody war between the U.S. and Mexico just a few years prior to Cinco de Mayo in which Mexico lost most of its territory.
Explanation: (I could be wrong tho idk tbh)
Because they were hunting dogs and cats to eat so they can survive . Also the government wasn’t helping them