I have been mixing my own goat grain blend for a few years. The results have been good with my herd. I have a few reasons for deciding to mix my own grain, instead of using commercial, pelleted, pre-mixed feeds. First, it is cheaper per pound to buy the ingredients and mix the grain at home than to buy bags of pelleted feed. Second, there's no molasses or fillers in homemade grain. Third, my goats look and act healthier on my grain blend than on commercial feed.
My grain blend consists of 70% whole, steamed, or crimped oats (I haven't found a difference between the three so I just get whatever is available), 20% poultry scratch grains (cracked corn, oats, barley), 10% black oil sunflower seeds (BOSS). I mix this up in a large tote bin. Any leftover grain gets stored in another tote bin until I am ready to mix up the next batch. It's important to have a secure and dry place to store your grain blend ingredients. Since I am mixing parts of different sacks of grain, I wind up with leftovers in the bags and have to have storage available.
I feed this grain blend to all my goats. My non-pregnant or non-lactating goats get 0.5 lbs of grain per day. My pregnant goats start gestation at 0.5 lbs per day and end gestation at 2.0 lbs per day. I then increase the grain to 3.0 lbs per day at 1 month of lactation. Depending on how much milk the goat is producing, I will increase to a maximum of 4.0 lbs of grain per day. I decrease the amount slowly as lactation decreases.
This grain blend is fed along with Chaffhaye alfalfa silage. It is extremely important to provide all goats with a source of alfalfa daily. Goats need calcium in their diets and alfalfa is high in calcium. Along with building strong bones and being a major component of goat milk, calcium also helps balance out dietary phosphorus to keep goats healthy. Too much phosphorus can lead to urinary calculi, pregnancy toxemia, hypocalcemia and other health problems. All grains and feeds made from them (corn, oats, barley, wheat, sunflower seeds, etc) contain high levels of phosphorus. Grass and grass hay is also high in phosphorus. Thus when feeding any grains/feeds and hay or pasture to goats, you MUST provide alfalfa. I use 2 lbs of Chaffhaye per goat per day. Due to our calcium-poor soils in the North Country, it is even more imperative to provide calcium-rich alfalfa to your goats because the goats will get very little calcium through grazing.
When feeding a home-made grain blend that doesn't contain any mineral supplements, it is very important to supplement your goats with the extra minerals they need. The best way to do that is to provide a loose mineral blend designed specifically for goats. Sweetlix Meatmaker 16:8 is a good mineral blend that goats will readily consume. It is available through special order at most feed stores. Leave a pan of it out at all times so the goats can eat it as they choose. Be sure to clean and refill the pans often. Do not use salt licks, mineral blocks, or non-goat specific minerals. These do not contain enough of the essential minerals that goats have to have. It is also important to add copper and selenium to your goats along with their daily minerals. In the North Country, most goats are copper and selenium deficient due to our poor soils. Copper can be supplemented by using Copasure boluses for goats every 6 months. Selenium can be supplemented by using Selenium/Vitamin E gel for goats every month.
Mixing your own grain can be a positive choice for your goat herd. Be sure to do lots of research on goat dietary needs before planning to mix your own grain. If you do change your goats diet, be sure to watch for any signs of health changes. Change diets slowly and keep goats on the same diet for a few months to best assess the results.