calcium - phosphorous ration

Question
I am looking for some nutritional advice, and I wonder if you could help me.  Is there a website that would let me know if I am calculating the calcium to phosphorous ratio correctly?  My 1300lb horse currently eats:

8lbs   Alfalfa Hay
16lbs Grass Hay
8oz    Whole Flax Seed
(at this dose contains 416mg calcium, 1056mg phosphorous)
4lb     LMF Senior          
(at this dose contains    .12% calcium, .08% phosphorous)

I just want to make sure that I am not overdoing the phosphorous.  If you could help that would be great.

Sincerely,
Sandy Wangberg

Answer
Hello Sandy,

Thank you for your question.  If I use average Ca and P values for your alfalfa and grass hays, I end up with a 2:1 calcium to phosphorous ratio, which in my opinion is good.  Not only is the ratio of these minerals within acceptable range, the daily intake of both is well suited to what I assume is a horse in light to medium exercise (based on your horses DMI).  There is a comfortable dietary excess of both calcium and phosphorous to ensure there is no period of mineral deficit, without there being a tremendous excess of either mineral in the diet.  My only word of caution is that in using the average Ca and P content of the forages, there may be some inaccuracy in the calculations.  Growing conditions can greatly affect mineral concentration in forages, and if the forages grew in a very wet growing season they might have a considerably lower mineral content than the average.  If you have true concerns with mineral content (seen as transient lameness) you might want to consider having your forages tested for nutrient content.

I hope that helps.

Thanks, Corlena