For the Love of the Dog posts here on the seven states that still have not adopted felony animal cruelty provisions. Alaska, Arkansas, Idaho, Mississippi, North Dakota, South Dakota and Utah still don't punish even the most egregious cases of animal cruelty as anything other than a misdemeanor. However, the ranks of shame are dwindling - Hawaii recently left the list after passing a new animal cruelty law that has a felony penalty.
The Animal Legal Defense Fund publishes a list available through this link detailing which states have felony animal cruelty statutes, and when they were passed. Notably, Florida was a leader in this regard having added a felony animal cruelty provision in 1989, making it one of the first states to have done so.