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

There was a weaning strategy × ITM interaction for the percent of steers walking on day 2 where AbtMM steers walked the most. Although authors expected abruptly weaned steers to spend more time walking after separation due to greater stress, it is difficult to explain why AbtMM steers walked more than AbtSAL steers. As hypothesized, the current study showed that two-stage weaned steers vocalize less frequently than abruptly weaned steers on both days 1 and 2 and there was a lower percentage of two-stage weaned steers standing and walking on day 1 compared to abruptly weaned steers. In addition, two-stage weaned steers spent more time lying on day 1 and eating on both days 1 and 2 compared to abruptly weaned steers. This is similar to previous observations (Haley et al., 2001 (Haley et al., , 2005 ) that on days 2 and 3 after separation that calves weaned in two stages with the use of anti-suckling nose flaps walk less, spend more time eating, more time lying, and less time standing than calves weaned by traditional abrupt separation. These mentioned findings clearly demonstrate that two-stage weaned calves display less behavioral signs of stress upon separation from the dam than calves weaned by the traditional abrupt separation method. However, calves were not observed for behavior and vocalizations during the 6 d while nose flaps were inserted in two-stage weaned calves, so there is no data to compare behavioral stress of treatment groups prior to separation. Though cortisol levels were not different, based on behavior parameters, it is possible that the two-stage weaned calves were not as stressed upon entering the feedlot compared to the abruptly weaned calves. However, a potentially more complicated interaction between ITM and level of stress may exist.