Manufactured Feeds
Always read the ingredient lists on every single feed bag.
While most feed manufacturers provide a nutritional analysis and list of minerals, not many feeds provide an ingredients list - and it is the ingredients list that tells you what is in there. If you don't know what is in there you don't know if that feed is safe for your horse.
Rule 1: If there is not an ingredients list, then consider whether you should buy it. I wouldn't myself!
If I don't know what is in that bag it is just not going in my horse! I now have a policy of not purchasing any product for my horses (or for myself or my children for that matter!) that does not have a full ingredients list, or one that contains such vague terms as "cereal derivatives" or "materials of vegetable origin"
Rule 2: Never trust the marketing or any approval logos on the bag
Labels are simply a general indictation that the feed may be suitable for a particular type of horse. Often “low sugar” feeds still contain molasses/glucose/syrups and “cereal free” feeds can contain cereal by products and questionable substances like wheat syrup.
For some compounded feeds there can be many tens of ingredients - so how do you know which one your horse may be intollerant to or gives them problems?
Rule 3: Understand the feed rates
Many horse owners (me included at one time) read the nutritional information and assume that this will provide all my horse and pony's needs - but it is important too to understand the feeding rate - a horse getting 500g of the feed is getting far less nutrition than a horse getting 2Kg of the same feed. Often it is quite simply impossible to feed at the manufacturer's recommended rates or we have one very round, very satisfied pony!
Rule 4: Be realistic about what you are paying for!
Another consideration with many bagged feeds is simply that if you are buying 20Kg of a feed for £8.50 then the content of the feed must be made up of quite low cost ingredients to be able to make the feed and cover all of the manufacturer's production, marketing, distribution, administrative, sales costs and wholesaler and retailer profits and costs! Any vitamins, minerals or herbs in there are going to be the lowest cost materials.
Just think about it that way, and the feed becomes less palatable! The same applies to your own food - cheap, bulk food is cheap for a reason!
Many supplements are very smartly packaged and carry a price tag that reflects the "value add branding" of the packaging and marketing materials. Don't buy a supplement just because it is smartly packaged, or endorsed by a leading equestrian personality. For example a commonly used "calmer "contains 1KG for £22. The major ingredient is Calcined Magnesite which is available from farm stores for £8 for 20Kg! Seaweed sold by NAF works out at £10 a Kg, but you can buy the same seaweed from Agri stores (SeaQuim) for £25 for 20Kg - quite a markup for NAF!
Rule 5: "Safe" is a relative term
Be aware of free flowing chaffs. These seem to cause problems for some sensitive horses, even when they only contain apparently “safe” ingredients. It is not yet clear what the trigger is, although it may be the mould/fungal inhibiting agents that are added or sprayed on to such chaffs. Some owners of barefoot horses have found tha tthey can tollerate pelleted alfalfa where they cannot tollerate the flash dried form, it is unclear why this should be the case but it may be that the pelleting process destroys some of the sugars in the alfalfa.
For a footy horse it is always worth while eliminating compound feeds and then checking for improvement. In any event good quality hay is a cheaper and better form of fibre for most horses.
Feeds that are "low starch," "reduced starch," "safe," etc., aren’t necessarily low calorie. In many cases, the calories that were coming from high-starch grains and molasses have been replaced by fat calories. Because they’re not necessarily low calorie, you can’t substitute these feeds for your current feed and expect your horse to lose weight. Dietary fat increases or even causes insulin resistance in other species. It’s known to cause insulin resistance in ponies; there’s some evidence to suggest caution with feeding high-fat feeds to insulin resistant full-size horses as well.
Supplements
"The equine marketplace is flooded with supplements, each designed to address a problem that has it's roots in inadequate nutrition." Dr Kellon VMD
There are many supplements that are useful and will support your horse. Some are surprisingly inexpensive (such as seaweed) and some are eye wateringly expensive and may not deliver any real benefits. Some supplements can actually cause harm to sensitive horses and recent high profile fatalities in the US indicate that supplements should be used with caution.
Some thoughts around supplements:
Know what you are supplementing for - have a reason for supplementing. If your horse is already getting sufficient, additional supplementation is a waste and may even be toxic.
Don't just use a feed balancer because everyone else in your yard is using this or that feed balancer - or your riding instructor likes that brand. Your horses diet should contain everythign they need without resorting to a feed balancer - and in any case none of these companies will tell you what is in the feed balancer - so back to Rule 1 - if it hasn't got a complete ingredient list then don't feed it!
Maintain reasonable expectations around what supplements can achieve. A supplement may take several weeks or months before a tangible result is seen, if at all.
There is no point supplementing something your horse does not need. For example a "magnesium calmer" will probably have very little or no effect if your horse is not deficient in magnesium!
Supplements need to be fed consistently for best effect. Just as you would take your multi-vits every day, feed the supplement at the recommended dose every day.
Some compounds, such as Rosehips and Schizandra, are adaptagens and can address a number of different issues as needed.
Often a supplement will only be needed for a short time and then its effect will wear off. The horse will take what he needs to effect repair and then discard what he does not need. Continuing to feed the supplement after that point is a waste.
One of the cheapest and most useful supplements that can help coat and hooves is simply seaweed. It is cheap, readilly available and you are paying for the supplement, not the marketing hype or fancy packaging.
Owning horses is expensive enough - smart buying can help you to focus your limited finances where you really need to. Shop wisely, save your money for doing fun things with your horse.