Substituting grain for hay is economical when roughages are in short supply. Since grain costs more per pound than hay, a smaller amount of grain must be fed to economically substitute for hay. This will require restricted feeding of grain.
The most economical diets are those diets that have almost no hay at all. Dr. Steven Loerch et al. (1995) fed 3 lbs. of hay, 3 lbs. of supplement, and 10 lbs. of whole shelled corn per cow per day during November and December. The cows received 3 lbs. of hay, 3 lbs. of supplement, and 12 lbs. of corn until spring turn-out. The cows averaged 1,300 lbs. in this study. Dr. Loerch recommends taking three to Four days for adjusting the corn and decreasing hay to the two- to three-pound level. The facilities need to be fairly secure. The supplement that was used follows:
| Feedstuff | % |
|---|---|
| Ground Corn | 31.95 |
| Soybean Meal | 45.60 |
| Urea | 4.10 |
| Limestone | 7.80 |
| Dicalcium phosphate | 4.30 |
| Trace mineral salt | 3.20 |
| Dyna K | 2.30 |
| Selenium premix (200 ppm) | 0.40 |
| Vitamin premix | 0.20 |
| Rumensin 60TM | 0.15 |
Hay-restricted diets will be the most economical, but secure facilities to control hungry cattle may be limiting for some producers. Therefore, for those individuals with limited facilities, substitute grain for only part of the hay or roughage (Steeds and Devlin, 1984; Whittington and Minyard, 1988). A minimum of one-half pound of hay per 100 lbs. of body weight is suggested (approximately 5-6 lbs. of hay/day). During extremely cold weather or in pastures with little winter protection, the hay could be increased to three-fourths of a pound of hay per 100 lbs. of body weight (8 to 9 lbs. of hay/day).
Additional hay can be provided in the form of very mature, low-quality hay or straw bales placed in hay feeders. This could be provided in addition to the previously mentioned hay. This hay, however, must be purchased or produced at a very cheap price to maintain an economical diet. Moldy hay is not cheap at any price.
The amount of grain necessary for each cow will depend on the initial condition of the cow. From 8 to 12 lbs. of grain is suggested, with lower-conditioned animals receiving the higher amounts. Increase the grain allowance during the last two months before calving.
Include a protein supplement during the last two months of pregnancy if low-quality forages are fed. Lactating beef cows can be fed a 50% straw-based diet without rumen-impaction problems occurring.