colt

Question
what is diffrent between a cold and a stud colt

Answer
Dear Amelia,
A "cold" is a virus and a colt is a young (three or under) un-castrated male horse. I am assuming that you REALLY meant to ask, "What is the difference between a "colt" and a "stud colt?" Technically there is no difference although "stud colt" is usually reserved as a term of reference for a male foal that is destined to become a breeding stallion.
I hope this answers your question.
S. Evans