Evolution of animal cruelty laws

I just found a phd thesis by a Daniel L. Moorehead from Central Missouri State University. It's a 2004 thesis titled:

The evolution of animal cruelty laws: A comparative analysis of animal cruelty laws in the United States and Europe

Here's the abstract:

This study examines animal cruelty laws in both the United States and Europe. It provides a thorough comparative analysis of existing laws regarding companion animals, farm animals, and animals raised for food. Documented evidence shows that continued violations of the Animal Welfare Act, the Animal Transportation Act and the Humane Slaughter Act persist in the United States and Europe. Unfortunately, the United States is by far the greatest violator of these laws due in large part to greed and the animal's status as mere property. Unlike the Europeans, who consider animals as sentient beings, the United States places little value on an animal's life other than its immediate profitable value to humans. The very government that has enacted laws to protect animals from maltreatment is the very one who sanctions the atrocities inflicted on innocent animals.