Yes, the hooves get dry. Dry hooves are definitely not a good thing (well, depends what you mean by "dry", if you mean it as in "not wet" then I guess it's good...). My horse's hooves get extremely dry in the summer and crack easily if not moisturised and you don't want your horse's hooves to crack. They're minor cracks but I won't risk leaving it alone for the cracks to expand. By the time I start putting the moisture on (sometimes twice a week, sometimes every day - my farrier always tells me how dry the hooves are) the cracks stop creating and expanding, the farrier does his best to fix the worst ones and we just wait for the hoove to slowly grow new and healthy again. I said I bought a crappy moisturiser in my previous post and it did some serious damage. I thought it is somehow helping though I didn't see any results (everyone in the stable recommended this one to me) and then once I came to the stable in the morning and my horse's shoe was hanging on one single nail, the rest was... chopped off off the hoof... I don't know how to describe it.
This is exactly the way my horse's hooves crack though I've never let it go this far. Basically where the nails are in the hoof, it was chopped off so the shoe had nowhere to be attached to it.
Why were you using the moisturiser? You said you used it but it didn't do any good and then you're stating that you don't even know what moisturisers are for. If you were using it "just to try it cause you saw it in the shop" I'm not surprised it didn't help you. It's not a thing to mess with. Too much moisture and especially there where it's not needed and you can create much more serious problems. It's a matter of climate your horses live in, their health, the way you care for them... While some horses will never have problems with their feet in their lives, some horses have them regularly and some horses experience them once or twice in a lifetime due to change of feed, pasture, bedding... My horse gets dry and cracked hooves in the summer when the temperatures reach far beyond 30°C (90°F - 90°F), July and August being the worst time of the year when the ground is rock dry and walking on it almost equals walking on concrete. It's just like fingernails. Mine used to crack a lot, I was always dreaming about having long nails but they always cracked or tore when I tried to grow them longer. A few years of healthy food (ok, not really healthy, but much healthier than I used to eat before
), vitamins and proper care and my nails (along with my hair) are much stronger and I can finally enjoy having them long!