My mare just had Casslicks done this fall. She had a
foal in May 2005, and tore some during the birth. She did "wind suck", and
it is a most unpleasant sound. I have lived with remarks by fellow riders,
such as "What is that noise pray tell?", (poetic license adjusted phrase) as
their faces contorted into a memorable conformation. Undaunted, I
have answered politely that she had done that since foaling, please
pardon.
However, I noticed a change in her during her last heat
cycle which included occasionally plopping out a copious clear discharge, and
squatting even more often. I feared perhaps urinary or vaginal
infection. Took her and a urine sample to the vet to get it checked
out. She recommended the Casslicks to me. She explained that the air
sucking irritated the tissues, and made them more prone to infection as well as
the obvious larger opening for that which don't belong there. It turned
out she had a vaginal infection, and was put on a round of
antibiotics.
She did ask if I intended to breed her again, which I
don't. She said she makes the closure a bit different in that
case.