Which of the following is NOT a common horse parasite treatment?

Amoxicillin is not a common treatment for horse parasites because it is an antibiotic primarily used to combat bacterial infections, rather than a dewormer. In contrast, Moxidectin, Levamisole, and Ivermectin are antiparasitic medications specifically designed to target and eliminate various internal parasites in horses, such as roundworms and bots. Each of these antiparasitic medications works differently—Moxidectin and Ivermectin are part of the macrocyclic lactone class, while Levamisole is an imidazothiazole. Therefore, while Amoxicillin serves an important role in treating infections, it doesn't fit into the category of parasite treatments commonly used for horses.