foal
The word used for one set of offspring is "progeny."
Fdikvg
as long as they get together and as long as they are both horses, yes, there will be offspring.
Foal.
A Foal
Foal.
A foal is the offspring of a horse but if you must be more specific a girl baby is a philly and a boy baby is a colt.
Fdikvg
That is a mule.
When a donkey and a horse breed, the offspring will be called a Mule. Due to the uneven number of chromosomes the offspring will be sterile.
mule
A foal