If it's not one thing it's something else at the moment! We've had some unusually wet weather lately and with it, all four horses on our property have had thrush, plus a friend's horse two doors down.
My gelding has pretty shocking feet to begin with, walls that chip and crack the moment they're a few millimetres on the longish side... his soles are nice and hard, though his heels are underrun and I don't know how to fix them. Will be asking the mother for help on that one I think, she's the real hoof trimmer in the family and has rehabbed various hoof problems despite the fact that all her knowledge is from experience and a 2 day clinic.
My filly was the first one that showed it up by suddenly going dog lame on her off hind (no sign of it beforehand). Within days the others all had smelly thrushy feet as well, but nobody else went lame. Picking up said filly's feet can be difficult, mind, so she might have been incubating it for some time. I haven't had her very long. She's still a bit lame on hard or rocky ground, but considering the state her frog's in I'm not surprised.
Currently, we have, between us and a friend, 5 horses... and TWO are rideable. My gelding and the friend's half-Arab pony. Out of the 5:
One mare has something going on where she all but throws herself on the ground the moment you touch her mouth under saddle, but is fine on the ground
One gelding has a swollen sheath from an insect bite (friend's pony)
One filly is lame from the damage that thrush has done to her offside hind
Other filly has a snotty nose (we're talking thick opaque yellow/green)
And other gelding is a-ok except for some rainrot scabs on the backs of his hind legs and a couple where the girth goes
Only one of us can ride with a saddle at the moment and that one of us is not me! Needless to say, I'm too lazy to ride bareback every single time I ride, so I go without quite a lot... would rather work with my unbroke slightly dangerous TB filly than ride my safe finished event horse bareback!
I'm just sick of something happening (or in this case multiple somethings) every time we bring a new horse onto the property... ugh!