Hello Dr Getty,

Our hay is low in crude protein, about 8 percent, which means that the digestible protein is probably around 6 percent. So I have been supplementing with about 2 oz daily soybean meal. We have one pregnant mare that I plan to go up to about a pound daily during lactation.

But now I recently read where soybean meal is high in omega 6s, so high that it could throw off the balance of 3/6s. I already add 3 oz of stabilized flax daily so my 3s are being boosted, but I am still concerned about the soybean meal.

I have considered using whey isolate instead. Isolate instead of concentrate because isolate has no lactose, right? Whey's amino acid profile seems to be better overall than soybean meal, just not as much lysine.

How much whey should be fed daily, or do you disagree with switching to whey from soybean meal or do you have a better suggestion?

Thanks

Where are you from? North Florida

Hello Billy,

Whey protein is an animal source (milk) and therefore is of higher quality than a plant source. You could feed the isolate (less lactose, as you mentioned) instead of soybean meal to keep the fatty acids in balance. However, two ounces of soybean meal (by weight) is not going to make a significant change, especially if you add more flaxseed meal.

In general, I recommend adding more flax -- you mentioned 3 ounces. If that is by weight, it would be equivalent to 6 fluid ounces (3/4 of a cup). I recommend feeding 1/2 cup (2 ounces by weight) per 400 lbs of body weight.

During lactation, she does requires at least 1535 grams of protein (for an 1100 lb mare), so figure the amounts accordingly by adding more whey, rather than soy.

Happy Foaling!

Dr. Getty
Author of Feed Your Horse Like A Horse

Where are you from? Bayfield, CO