Which term refers to something that is of, or relating to swine?

The term that refers to something that is of, or relating to swine is "porcine." This term is derived from the Latin word "porcus," which means pig. It is commonly used in veterinary science and agriculture to describe anything associated with pigs, whether it relates to their anatomy, behavior, or industry practices in swine production.

In contrast, "equine" pertains to horses, "canine" relates to dogs, and "galline" is associated with chickens. Each of these terms has its roots in different species, emphasizing the importance of specificity in terminology within veterinary and agricultural contexts. Therefore, "porcine" is the correct choice for anything relating specifically to swine.