Nutrition and General Health
I debated discussing this but I decided that it's so important I needed to. Horse nutrition is a HUGE topic in which I have no real scientific knowledge or education. Google it, look it up on the Chronicle forums, ask around, whatever. There is a ton of varying opinions of feed this, feed that, don't feed that because the horse may dieee *cue fake dramatic shriek of horror*.
A happy, healthy horse always looks the best. Horses are meant to move and graze 24/7. Very often, especially in this area of the US, do horses live outside 24/7 in an area that they receive the type of lifestyle their wild ancestors had. I believe (and this is strictly opinion) that all horses should be kept up to date on any vaccinations that are recommended by a respected, knowledgeable veterinarian in that area. All horses should be given dewormer at the recommended dose at the correct time. Teeth should be taken care of as well by a vet or equine dentist. Horses should be conditioned and worked correctly, to help build up proper muscles so they can be happy doing their job at the highest level. They should be turned out as much as possible. The farrier should be out to trim or reset shoes every 4-8 weeks depending on the time of year and the horse. Above you, you need to listen to your horse. A fat or super skinny horse isn't going to look as nice as a well conditioned one in proper weight, no matter what the coat looks like.
High quality hay is always the start of good nutrition. It keeps horses happier, busier, and is very well suited for the grazing 24/7 lifestyle. If you horse needs extra calories, then start including grain. Tons and tons of grain does not create a high show bloom. That said, while prepping yearlings at work, we strictly limit their hay intake to avoid "hay bellies" and give several pounds of grain a day. It works. But these are yearlings on a strict feed regime, a strict exercise regime and closely monitored every single day to prevent OCDs, create a high shine coat and make them manageable. This is only their lifestyle for two to three months while they were in the barns for preparation for sales. It is NOT a long term feeding plan. All horses should have access to clean, fresh water at all times and I'm a personal fan of salt blocks. Buy the highest quality hay and grain you can buy and you should be fine in that catergory. If you have questions, ask your trainer, your vet, the barn manager or a knowledgeable friend.
Nutrition matters. The yearlings come in on one type of feed (I won't name names just in case) and we have a 7 day period that we switch them over to a new, higher quality feed. From our daily 30 minute grooming and the new feed, the horses look phenomenal when they leave for the sales. It's only a few months time span. The fat ones who get less feed usually have worse coats that we have to groom that much harder to make shiny. Coincidence? I'm not sure. That's for you to decide.
Be careful to provide the horse with the recommended amount of protein, vitamins and minerals for the age and workload. If you don't meet the recommended feeding amount on the back or tag of your feed bag, you may want to consider switching feeds or supplementing with a vitamin/mineral product (think Centrums for horses!) or a ration balancer. Many feed companies have ration balancers. Speak with your vet, knowledgeable person, etc etc or a feed specialist from the company you use if you have questions. (FYI - The difference between a vit/min supplement and a ration balancer is that a ration balancer contains protein as well as vit/min. Both are low calorie which is great for those chubby horses, though the vit/min supplements tend to be lower if you have a super easy keeper.)
Supplement and product wise, there's a TON out there. I've heard many, many reviews on this supplement or this spray or whatever. As a short term fix, yes products work. Showsheen DOES make them shiny for a day. Healthy Hair Care does make them shiny. I'm sure lots of other spray on products do as well. I just don't have the time or energy to list all the ones I've used or heard about. I've heard tons of good things about Omega Horseshine, SmartShine, and personally I've noticed a different since Digby's been on the Smart Omega3 to help with his lameness which isn't supposed to be for coats/shine but it has a lot of Omega 3s (hence the name) which help with shine. There are lots of options out there. I attended a lecture while I was in school given by a miniature horse breeder and winner of several national in hand competitions who swore up and down about feeding sunflower seeds for shine. Flax seed and linseed are also really popular at the moment. Honestly, while I think it probably helps, elbow grease is free. If you have a high quality feed and hay, you should have a healthy horse. A healthy horse is a shiny horse!
Even in poor, low lighting Fashion Gabby is a shiny colt! This is with NO spray on products or feed thru supplements to his feed. Nutrition matters! :)