I know that it is winter and horses put on an extra layer of hair to stay warm. I drove by a neighboring farm and saw one of their horses had patchy hair, it was not full and even. I am wondering if it is just the winter coat or if it is being undernourished.

It could well just be the winter coat. They do not always come in thick and beautiful and even all over, some end up looking raggedy and messy for a good long while!

They can definitely end up looking rather ragged through no fault of the owner. Sometimes its because they get caught on things or grow in at uneven rates or the nutrient levels change. You can never tell without a detailed history.

All right I gues I was being a worrier. I will keep an eye on them but I am not going to lose sleep over it. Thank you for reassuring it should be alright.

Really, don't stress. My horse looks messy in the winter and it really bothers me when riding her. I hate the thought of that ragged and long hair getting caught up or pulled under the saddle.

Anyway this is common, though I don't know why it happens.