Alfalfa is fine for them..
The layer feed I use has it in there infact in the winter I add wet alfalfa meal in with there scratch.
Here is a copy of the feed tag from the web page of the feed I use..
GUARANTEED ANALYSIS:
Crude Protein, Minimum 18.00%
Lysine, Minimum 0.89%
Methionine, Minimum 0.37%
Crude Fat, Minimum 3.50%
Crude Fiber, Maximum 4.50%
Calcium (Ca), Minimum 3.00%
Calcium (Ca), Maximum 4.00%
Phosphorus (P), Minimum 0.55%
Salt (NaCl), Minimum 0.10%
Salt (NaCl), Maximum 0.60%
INGREDIENTS: Ground Corn, Soybean Meal, Porcine Meat and Bone Meal, Wheat Middlings, Corn Gluten Meal, Alfalfa Meal, Animal Fat (preserved with BHA), DL-Methionine, Calcium Carbonate, Salt, Calcium Phosphate, Manganous Oxide Ferrous Sulfate, Copper Sulfate, Zinc Oxide, Ethylenediamine Dihydriodide, Sodium Selenite, Vitamin A Supplement, Vitamin D3 Supplement, Vitamin E Supplement, Menadione Dimethylpyrimidinol Bisulfite (source of Vitamin K Activity), Riboflavin Supplement, d-Calcium Pantothenate, Niacin Supplement, Vitamin B-12 Supplement, Choline Chloride, Folic Acid, Pyridoxine Hydrochloride, Thiamine Mononitrate, d-Biotin.
FEEDING DIRECTIONS: Feed as the sole diet to laying hens and breeders for maximum production and for improved hatchability. Hens may also be fed 5 pounds of Buckeye Layer-Breeder Pellets per 100 birds daily along with their regular ration to encourage additional daily feed intake for increased production. Maintain a clean,fresh supply of water and oyster shells available to the birds at all times. For top production, maintain light on the birds between 14 and 16 hours per day. Do not feed Buckeye Layer Breeder Pellets to poultry which are not in production because of the high calcium levels in the diet. This is particularly true of young growing birds.
Chris