Efficiency is output divided by input. When discussing beef cattle efficiency, this is usually measured with feed intake within a controlled environment such as a feedlot. However, mature cattle that make up the US cow herd live primarily outside of confinement in open pasture and range systems. The main goal of this research was to characterize the forage intake of 24 two-year old lactating cows at both mid- and late-lactation while grazing sagebrush steppe rangeland during June and August 2016. This herd of cows had been previously classified as either efficient or inefficient in a drylot system. To determine their range forage intake, gelatin boluses delivering 4.5 g of alkane were administered orally at the start of the two collection periods. The release of the marker into the lower tract was measured over the next 4 d by collecting fecal samples from the animals. There were no differences between efficient and inefficient cows for the intake variables measured but differences were present between grazing periods. Reasonable, though slightly inflated, estimates of intake with the pulse dose procedure were obtained but differences in intake in a feedlot setting did not translate to a range setting.

Read the full article in the Journal of Animal Science.