Final answer:
Ear tags are a common form of identification for swine animals, while nose rings, electrolysis, and shingling are not.
Step-by-step explanation:
Ear tags are a form of identification for swine animals. They are small plastic or metal tags that are attached to the ear of the animal. These tags usually have a unique alphanumeric code that can be used to track and identify the individual swine.
Nose rings, on the other hand, are not typically used for identification purposes in swine animals. They are often used to control the behavior of the swine or to prevent them from rooting or digging.
Electrolysis and shingling are not forms of identification for swine animals at all.
Learn more about Identification of swine animals