When I bought my horse last fall his mane was thin, dry and frizzy. Tail was pretty sad and dry too.
I have been feeding him about 1 tablespoon of flaxseed a day for 6 months now and the new growth is thick, healthy, strong, soft and as shiney as horses going in the show ring coated with mane and tail shine enhancers.
I have never applied anything topically (although I am not against them) and he does still have a few fuzzes on the tips, but otherwise it is a pleasure to run my hands through his mane and tail now.
Hmm...i will have to try that olive oil trick! Also make sure to rinse the tail out really well after washing or the hairs will get frizzy. My horse rubs her tail as well when there is left over conditioner-not a pretty sight!