Performance and slaughter breakeven analysis of calf and yearling systems and compensatory growth

Four yr of yearling grow/finish systems were evaluated. In the first 2 yr, treatments were (1) animals grown at a ‘fast’ rate of winter gain (0.73 kg/d; FAST) using-wet corn gluten feed as an energy source and (2) animals grown at a ‘slow’ rate of winter gain (0.20 kg/d; SLOW). Treatments were designed to evaluate compensatory gain on summer grass. Summer forage intakes were measured in an attempt to explain any compensatory growth. Steers on the SLOW treatment gained faster during summer grazing compared to FAST; however, no differences were noted for kg forage intake/head. Steers on the SLOW treatment consumed more forage, as a percentage of body weight, compared to FAST. In yr 3 and 4, additional treatments were added: steers wintered at a ‘fast’ rate of gain using corn as an energy source (CORN), steers grown at a ‘fast’ rate of gain for half of the winter, followed by a ‘slow’ rate of gain (FAST/SLOW), and steers grown at a ‘slow’ rate of gain for half of the winter followed by a ‘fast’ rate of gain (SLOW/FAST). With this treatment structure, the effect of winter energy source and duration and severity of winter growth restriction were evaluated. Steers on the FAST/SLOW, SLOW/FAST, and SLOW treatments gained faster in the summer compared to FAST and CORN. Compensation ranged from 20–40%, and was not impacted by winter energy source or duration or severity of winter growth restriction. In addition, the 4 yr of yearling systems were evaluated in relation to calf-finishing (CALF). Only FAST and SLOW treatments were used. Steers on the CALF treatment consumed less feed and converted more efficiently, but gained less with more d on feed compared to yearlings. Steers on the FAST treatment were more profitable ($/head) compared to CALF and SLOW. Based on results from the above trials, steers must be fed to gain at increased rates over the winter to lower slaughter breakeven. Only 20–30% compensation on grass is realized following winter restriction