EFFECTS OF DIETARY VOLATILE FATTY ACIDS AND PROTEIN ON FEEDLOT PERFORMANCE AND CARCASS TRAITS OF STEERS
Sixty-nine head of Hereford steers were used to study the effects of three different levels of dietary protein (low, basal, and high) and two levels (0 and 5%) of volatile fatty acid (VFA) on efficiency of gain and carcass composition. Energy retention data was determined by using a comparative slaughter technique. The accumulation of fat resulted in higher gross efficiency of gain. A 5% addition of VFA resulted in 9% better gains. These data suggest that increasing dietary protein without simultaneously increasing dietary energy, as VFA, will not increase performance. However, when energy, in the form of 5% VFA and protein were added together, increased performance occurred. Increasing the level of dietary protein resulted in increased levels of plasma urea nitrogen and total ruminal VFA concentrations. Results of this experiment suggest that blood glucose levels increase when 5% VFA is added to each of the three dietary levels of protein. These results suggest that the addition of 5% VFA to each of the three dietary levels of protein provide a more readily available energy source than a non-VFA supplemented ration.