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Nutrition Table 3.  Daily added pounds of feed needed to maintain BCS on a 10 o F day with a 10-mph wind Table 4.  Energy reserves for cows with different body weight (BW) and BCS (NRC, 2000) Mature BW (lbs) at BCS 5 Pounds, as fed Grass hay 10.2 BCS 1,200 1,300 1,400 1,500 Corn grain 5.4 3 172 186 200 214 Corn silage 17.2 4 196 212 229 245 5 226 245 264 283 6 264 286 308 330 7 311 337 363 389 Additionally, these effects are cumulative. For example, when feeding corn silage, not only does the cow need an additional 17.2 pounds for managing cold stress, but she will require another estimated 4.5 pounds when prolonging lactation. This equates to an additional 22 pounds of corn silage required daily, simply to maintain condition. Adding condition A common situation is trying to put a “little condition” on cattle. Findings by the National Research Council (NRC) in 2000 have provided us with the information necessary to determine the appropriate nutrition required to change condition (Table 4). While each condition score results in roughly the same change in weight for a given cow (80–100 pounds), the composition of gain changes (more fat, less protein). Thus, it takes more energy to achieve each pound of weight gain for a cow with a BCS 5 compared to one with a BCS 3. *Mcal NE required or provided to change condition score So, how is this information practically applied? Cow feeding decisions require the following considerations: • What change in BCS is desired? • How many days do we have to make this change? LIMOUSIN Today | 53