Effect of a transitional diet on stocker heifers grazing wheat pasture

Abstract

Cattle on wheat pasture require an acclimation period before significant body weight gains occur. Weight loss is often observed during the adaptation period. The effect of energy supplementation while grazing wheat has been tested, and the effect of high energy diets during preconditioning before grazing wheat has also been tested. However, the strategy of designing a feeding program that continues from drylot through the transition to wheat pasture has not been explored. Therefore, a three-year study of three different diet strategies, including a combined (transitional) strategy was conducted and weights recorded daily using GrowSafe technology. A mixed model is estimated and, a partial budget is prepared for each diet strategy. Average daily gain differed significantly by treatment in the drylot phase (P < 0.05). On pasture, total weight-gain for cattle under the transitional strategy differed significantly from the other two treatments (P < 0.05) in the first 14 days. However, average daily gain did not differ significantly between treatments overall (P < 0 .05). This study reveals that the weight loss cattle experience during the transition period occurs during the first two days of wheat pasture grazing. Given that the transitional-diet strategy yielded no additional benefit overall, the net returns to such a strategy are negative. This study uniquely uses GrowSafe technology to reveal that cattle on wheat pasture lose weight quickly but rebound slowly.