20 yo and 7 yo OTTB. Moved 3 weeks ago to pasture. Had been on grass but it was pretty meager and were largely eating round bales.
Just noticed this past week both horses are growing mustaches. I noticed on the older guy first and thought this was a sign of getting old then I noticed the 7yo is also growing a stache.
They look good in every other way. Their coats otherwise look normal.
Is this a cause for concern? Has anyone seen an abrupt growth of hair like this? What on earth could cause this?