Evaluation of two-stage weaning and trace mineral injection on receiving cattle growth performance and behavior

Rauch, Jordan C; Stokes, Rebecca S; Shike, Daniel W

On day 0, calves were removed from dam, weighed, plastic calf weaner devices were removed from twostage weaned calves, and ORC calves were shipped via commercial trucking 272 km to Urbana, IL. Calves from Urbana were shipped via commercial trucking for an equal distance as ORC cattle so that calves from both facilities were subjected to similar shipping time and stress. Upon arrival, calves were reweighed and pre-trucking and arrival BW were used to calculate a percent trucking BW shrink for each calf. Upon arrival, calves were sorted by source and treatment and randomly assigned to pens (5-7 steers per pen [4.88 × 10.36 m]). Calves were housed in two identical barns. Barns were constructed of a wood frame with a ribbed metal roof and with siding on the north, west, and east sides. The south side of the barn was covered with polyvinyl chloride-coated 1.27 × 1.27 cm wire mesh bird screen and equipped with retractable curtains for wind protection. Pens had slatted concrete floors covered by interlocking rubber matting. Weaning method was separated by barn to minimize influence of other treatment on behavior. Calves were fed in 4.27 m concrete feed bunks and were offered ad libitum access to a receiving diet from day 0 to 6, a transition diet from day 7 to 42, a step-up diet from day 43 to 53, and a growing diet from day 54 to 124 (Table 1 ). All calves were weighed again on days 41, 42, 123, and 124. Day 0 to 42 was referred to as the receiving period. The growing period was considered to be from day 42 to 124 and overall period was considered day 0 to 124. Average BW from days 41 and 42 and days 123 and 124 were used to calculate average daily gain (ADG) for receiving and growing periods, respectively. Incidence of morbidity was recorded daily by animal care personnel throughout the duration of the trial.