What am I feeding my horse, anyway?

I've been wanting to write this post for awhile. I'm a little hesitant because I don't have complete control over what Will is fed, nor do I feel like I know enough to make those decisions myself.  However, I am taking steps to learn as much as I can about equine nutrition and figure out what exactly I am feeding "my" horse. [for ease of writing, I may refer to Will as my horse. Everyone at the barn does, so why not, lol].


To start the process of learning, I've been collecting info on what my horse is fed.  This is probably all a bit much but here is the run-down anyway.

He has unlimited access to hay (round bale, good quality first cut, grown on the farm) during turnout from about 6:30am to 8pm and has 2-3 flakes in his stall at night, depending on the size of flake. My boarding barn is pretty much full for indoor boarders so I've been lucky that Willy has had a stall most of the last 3 months. He did give up his stall for a week while one horse, normally on outdoor board, needed stall-rest. He lost it again recently so that the pregnant mare who usually lives outside could come in at night. He gets it back as of today because someone is moving their horse (yay for us!).

His feed consists of 2 feedings per day of a mix of Shur-Gain Equiline Xplosion, Shur-Gain Medallion, Finishing Touch, salt, and oil. The proportions are, 2 scoops each of Xplosion and Medallion, 1 of Finishing Touch, a tablespoon of salt (blue), and about 1/2 cup of oil (not measured precisely). Since I know many people feed by the "scoop" when it should be weighed, I brought my own kitchen scale to the barn and weighed each portion. I'm sure there is a slight degree of error on these measurements - I would have to repeat my scoops many, many times and take an average to be sure, but I doubt it would improve upon my initial measurements by much at all. I did repeat my own measurements a few times to get a sense of error and it was slight.

Details:
2 scoops Medallion = 1lb, 7.75oz
2 scoops Xplosion = 1 lb, 3.7oz
1 scoop Fin. Touch = 0.985oz

Now for the nutritional breakdown of each. I've included (and rounded) the daily totals at the top.

Medallion:
total daily ration =  2.44 lbs/1.11kg
Crude Protein (min): 35.0%
Crude Fat (min): 7.8%
Crude Fibre (max): 15.7%
Calcium (actual): 0.83%
Phosphorus (actual): 0.63%
Sodium (actual): 0.39%
Vit A (min): 9,970 IU/kg
Vit D (min): 1,895 IU/kg
Vit E (min): 394 IU/kg
Selenium added at 0.30 mg.kg


Xplosion:
total daily ration = 2.21 lbs/1.0kg

Crude Protein Min. 12.0% 

Sodium Act. 0.50%

Crude Fat Min. 10.0%

Crude Fibre Max. 15.0% 

Vitamin A Min. 11,000 IU/kg

Calcium Act. 0.85% 

Vitamin D Min. 2,200 IU/kg

Phosphorus Act. 0.60% 

Vitamin E Min. 300 IU/kg
Selenium added at 0.40 mg/kg 

Finishing Touch:
total daily ration = 1.23 lbs/0.56kg
(aside: I sent an email to Masterfeeds because the link to their nutritional info page wasn't working. They fixed the problem and responded in less than 24 hours)

Crude Protein (Min)  14.0%

Crude Fat (Min)        18.0%

Crude Fibre (Max)    14.0%

Calcium (Act)               1.0%

Phosphorus (Act)        0.60%

Magnesium (Act)         0.30%

Potassium (Act)     0.80%

Sodium (Act)  0.40%

Sulphur (Act.  0.20%

Flourine (Max)   60 mg/kg

Copper (Act)     35mg/kg

Manganese (Act)  110mg/kg

Zinc (Act)             110mg/kg

Cobalt (Act)         1mg/kg

Iodine (Act)     2 mg/kg

Iron (Act)             115 mg/kg

Vitamin A (Min)   12,000. iu/kg

Vitamin D (Min)   2,700 iu/kg

Vitamin E (Min.)    400 iu/kg

Selenium added at 0.300 mg/kg

And this is about where I lose any idea of where to go in terms of assessing the appropriateness of his rations!  I don't understand why there are no values for sugar/carbs. My main concern was whether he was getting too much sugar and equivalents. My other shortcomings are in knowing what a horse's typical dietary requirements are and how to calculate what he's actually getting based on the guaranteed analysis of his feed. If I could do that, I could compare the two and see where the deficits and shortfalls are. I would also need to know about regional variation - for example, I know selenium is deficient in this area but is there anything else? I have some homework to do, clearly!

Notes about the horse.
Willy is 5. Since I started working with him at the end of July, he has gotten this regime consistenly. He has put on weight and muscle. I was initally concerned about weight loss with working 5-6 days a week when he had been only getting 1 day a week. As the weeks went on, I saw that he was gaining condition and weight overall. He is in pretty good weight now but I'd be happy with a little more.  At stand still, you can't see any ribs but they can be felt easily. This was true even before he started gaining his winter wooly coat. When he moves, however, his ribs do become more visible.  A lot of people seem to like overly fat horses around here but I do not. I would be ok if he stayed the same weight or gained slightly but definitely don't want him to lose any.

Hooves - Willy's hooves have always been good, even when the trims haven't been. I don't want to go into too much detail in this post but it's hard since all things are connected! I will say that his hooves have improved concavity over the last few months. Also, the new growth (of which there has been a lot) is growing in very nice. He has several "ripples" on his external wall surface. Since I've been leasing, the new growth has been straight and true. I attribute this to the increased workload stimulating better growth in combination with better consistency in what and when he is fed grain. He is not "hot", though he can be a little looky/spooky/sensitive these times are quite easy to ride/work through.

All that to say, it doesn't seem there are any obvious problems with his feeding regime. Still, I would like to know how to better assess what he's eating with what he should be eating.  Here's to learning!