Likewise, the P requirement also decreases with increasing weight of the animal so DRC and HMC were gradually replaced with corn bran to prevent overfeeding of P. During the second year, calves were placed on finisher two and finisher one was skipped due to heavier initial weights than in year one. At slaughter, hot carcass weights and liver scores were recorded. Quality grade, yield grade and fat thickness at the twelfth rib were recorded following a 48-hour chill. Steers were fed in 12 waste management pens. Manure was sampled during removal and pen soil samples were again collected to estimate nutrient balances after the feeding period.
Soil sampling allows adjustment for inevitable cleaning differences from pen to pen.
These pens also contain runoff collection basins to determine total runoff from pens on different treatments. This improved efficiency may have been due to the addition of corn bran, which replaced dietary starch, and may have decreased acidosis-related problems with EXP steers. Yearlings on the EXP treatment were also fed HMC which may have improved efficiency. The increased feed to gain ratio is primarily due to year two where calf gains were reduced due to the wet, muddy winter and spring in 1998. The reduced efficiency in this scenario may be explained by the corn bran addition, and a lower benefit from corn bran in preventing subacute acidosis in the calves as compared to the yearlings.