Why are cattle called doggies?

Answer 1

A species is sometimes defined as a group of organisms capable of interbreeding and producing fertile offspring. Even though this definition is adequate, more precise or differing measures are often used, such as based on similarity of DNA or morphology.

So species might not be the best choice of words in this case, although anything is arguable :)

It refers to the male (bull) and female (cow) as a gender. In other words...

have no clue as to "why" :)

Answer 2

This term originated in the American West, where cattle ranchers often referred to their cattle as "doggies" as a term of endearment or familiarity. It may have been influenced by the cowboys' relationship with their loyal working dogs on the ranch.

Answer 3

This typically refers to a orphan or orphans. these cattle were difficult to keep in line on the trail and needed extra attention, thus slowing or " dogging the herd".