Planning for Winter Feed
By : Denise Schwab, ISU Extension beef specialist and Katy Lippolis, assistant professor of animal science at Iowa State University
It seems we just finally got to grass, but it is never too early to start planning for winter. Most producers used up most if not all of their hay carryover, so are starting with no reserves which makes winter feed planning even more critical this year.
There are many ways to approach winter feed planning, but a simple approach is to calculate feed needs versus feed available. Start with an inventory of all the cattle that you plan to winter, including replacement heifers, backgrounding calves and bulls in addition to the main cow herd. You’ll also need approximate body weights to use in calculating feed needs. Next, inventory the feed resources available, approximate weights, dry matter and quality.
To calculate feed needs, multiply the number of animals times their weight. A general assumption is that cattle will eat 2.25-2.5% of their body weight in dry matter per day, so body weight times 2.5% times the days gives you approximately the amount of feed needed.
An example would be:
- 100 mature cows X 1400 pounds = 140,000 lb. weight x.025 = 3500 lb DM/day x 150 days = 525,000 lb
- 20 first calve heifers X 1000 pounds = 20,000 lb. weight x.025 = 500 lb DM/day x 150 days = 75,000 lb
- 25 replacement heifers X 700 pounds =17,500 lb. weight x.025 = 437.5 lb DM/day x 150 days = 65,625 lb
- 6 bulls X 2000 = 12,000 lb weight x.025 = 300 lb. DM/day x 150 days = 45,000 lb
- 65 background calves X 650 = 42,250 lb weight x.025 = 1056 lb. DM/day x 60 days = 63,375 lb
This example would need 774,000 lb, or 387 tons of hay on a dry matter basis. Assuming hay is 85% dry matter, you need 455 ton of as fed hay. You also need to factor in some storage and feeding waste. Well managed hay feeding with good hay bale feeders probably need to factor in 10%-15% additional waste, so now you need about 524 tons of hay for a 5-month feeding period. This assumes you provide full feed of hay at all times.
A second step to forage planning is to allocate resources based on forage quality and nutrient needs at various time periods. First cutting hay usually comprises about half of the total hay crop, but also tends to be more mature and therefore lower in quality. It is a good feed for mid-gestation cows, and maybe bulls after they are back in good condition. Second and third cuttings of hay tends to be higher quality because they are less mature at harvest, and are best targeted to late-gestation, calving and young stock. Grass hay tends to be a good match for weaned calves provided it isn’t too mature.
There are many things you can do to reduce the amount of hay needed, such as grazing crop residue or cover crops, controlling feed waste, substituting lower quality forages such as corn stover, limit feeding forage and supplementing with corn or corn coproducts, or feeding an ionophore. But having a rough plan for feed needs provides you the opportunity to purchase or harvest additional forage during the growing year when those forages tend to be less expensive.