To fatten you want to lean more towards a high Carbohydrate diet than towards a high protein diet. Protein is more for growing muscle, carbohydrates tends to fatten.
The protocol that we followed with raising 4-H steers was first to put them on a high protein diet to "grow" them, and then gradually switching to a high carbohydrate diet towards the end.
We used steam flattened corn, oats and barley as it is digested /absorbed better than whole grains, and sometimes switched to straight barley towards the end. Barley is pretty hot and you can burn them out if you are feeding high volumes without roughage such as a good flake of grass hay to go along with it, so be careful with it.
Sodium Bicarb might be a good idea with high volumes of grain, not familiar with monensin, execpt heard that if horses accidently get into it, it is toxic to them.
Straight Alfalfa is a good feed if an animal is working ( milking etc) but pretty hot for animals that are not doing anything. Seen animals get the "runs" from it. although some animals it don"t bother.
Good to mix it with a bit of grass hay.
Most large feed stores have someone who is up on the different feeds,and sometimes there are government people who can give advice.
Hope that helps.
Nite Hawk
