By Garth Ruff
Are you having trouble keeping body condition on grazing livestock? Do you have heifers or ewe lambs that struggle getting rebred? If so, there is a good chance that a lack on available energy in your pasture or ration may be the culprit.
I have these types of discussions with producers fairly often, and usually (not always) supplementing additional energy into the diet seems to aid in rectifying the situation.
As managers we must remember that livestock utilize nutrients in waste not, want not hierarchy. Think of an order of operations where Maintenance > Development > Growth > Lactation > Reproduction > Fattening.
Therefore, an animal that is not maintaining body condition is less likely to reproduce. That first calf heifer that is thin at weaning, still has a requirement for growth and development before we ever think about getting her to a point where she will breed back in a timely fashion.
How do we address this lack of energy in a pasture-based system? Supplementation in some form or fashion is the most likely response, but I’ve many supplement strategies that vary greatly in effectiveness and cost.
Additional forage, AKA Hay – This strategy can work depending on the class of animal and quality of the hay. A high quality, 2nd or 3rd cutting, well-kept round bale of hay can often meet the needs of mature animals of the herd. In the case of the thin, first calf heifer, unless the hay is of exceptional quality it might keep her belly full but is unlikely to get her to a desired body condition.
Don’t guess. Forage test! Hay quality varies tremendously from farm to farm. Consider dry matter losses when buying hay. That year old bale that has sat uncovered in a fence row somewhere, no matter the cost is still over priced when you consider dry matter lost.
Tubs – Too often in these instances I’ve seen tubs relied on as a cure all. Look at the analysis of a tub and the ingredients and then compare the cost. Tubs may have a place in stocker situations providing weaned calves with some protein, but considering the cost and energy provided, they are likely nor cost effective in provided supplemental energy to grazing livestock. Also, not all tubs are created equal. To a degree you get what you pay for.
Grain – Pound for pound supplementing grain, typically whole shelled corn is a cost effective and efficient way to supplement energy in a grazing operation. Once we know the energy requirement of our livestock, we can calculate pounds of corn per head per day. In most instances it doesn’t take much corn to supplement the needed balance of energy.
Research conducted here at Ohio State looking at the supplemental energy requirements of third trimester bred heifers in muddy conditions vs those in dry conditions demonstrated that only 2.5 pounds of corn was needed to maintain body conditions. At $7/bushel corn that is a cost of $.25 cents per head per day, still very cost effective when compared to longer breeding intervals and open cows.
Bottom line – Supplemental energy is often needed to maintain grazing livestock through a typical Ohio winter. Consider cost and energy density of feedstuffs when making the decision to supplement animals on pasture.
Source : osu.edu