BACK TO QUEBEC CITY 2002 TITLES
A procedure to reduce
the stress of weaning on beef cattle: On-farm trials of two-step weaning
D.B. Haley1, J.M. Stookey1
and D.W. Bailey2
1University of Saskatchewan,
Saskatoon, Canada; 2Montana State University, Havre, USA
Two-step weaning prevents nursing between cow-calf pairs for a few days (step 1) prior to mother-young separation (step 2) and may have advantages over traditional weaning. Calves wear a nose-piece that acts as a barrier which prevents nursing by blocking access to the teats. The goal of these experiments was to test the practical efficacy of using this weaning procedure on beef cattle operations. In trial 1, 175 cow-calf pairs (calves = 36±2 weeks of age) were randomly allotted to one of three weaning procedures that prevented them from nursing for 14d (n=57), 3d (n=58) or 0d (control, n=60) prior to separation. Two days prior to separation, cows and calves on the 3d treatment were observed to be in closer physical proximity to one another compared to the other treatments. After separation, transportation and overnight rest, 30 calves from each treatment were moved to experimental pens for two days observation. Fifteen pens contained 6 calves each (n=5 pens/treatment). Instantaneous sampling showed that after separation, two-step calves (14d and 3d) behaved remarkably similar to each other, but dramatically different than controls. Control calves called at a rate 28 times greater than two-step calves (P<0.05) and walked four times as much (P<0.05). Two-step calves were observed eating (P<0.05) and lying-down more frequently (P<0.05). Calves deprived of milk for 14d were lighter than calves from the other treatments 8 weeks after separation. In trial 2 nursing was prevented for either 5d (n=50) or 0d (n=50) prior to separation for pairs of similar age to trial 1. All calves were weighed 5 days before separation and on days 0, 7, 14 and 52 after separation. Two-step calves gained the same as controls during step 1. During the first 7 days after separation, two-step calves had a higher average daily gain, but this was reversed during the second 7-day period. No overall difference in weight gain was detected 52 days after separation. In trial 3, again with calves of similar age to the other trials, we used pedometers to record the walking behaviour of calves separated after 5d (n=5) or 0d (control, n=5) without nursing. Focal calves wearing pedometers were a subset of 50 calves, 25 from each treatment, all being kept together in the same pen. Applying the same average stride length to all (75 cm), controls walked twice as far as two-step calves during the first two days after separation (40 vs 15km; P<0.05). Two-step weaning drastically reduces the behavioural indicators of stress associated with the traditional abrupt method of weaning beef cattle and is easily applied to production systems.