Reducing weaning stress in beef cattle Derek B. Haley and Joseph M. Stookey Large Animal Clinical Sciences Western College of Veterinary Medicine University of Saskatchewan, Saskatoon, SK INTRODUCTION Beef cattle are traditionally weaned by the abrupt and permanent separation of cows and calves, which is stressful and dramatically different from the natural weaning process. As a result calves gain less weight and many get sick and need to be treated. Finding ways of reducing weaning stress can help alleviate these problems and improve cattle welfare (Fig. 1). OBSERVATIONS Behaviour was observed (12 h/d) during 3 distinct time periods: BASELINE period, for 4 d before experiment started NO MILK period, for 4 d two-step calves unable to nurse but still with their mother, control calves were still nursing SEPARATE period, for first 4 d after pairs had been separated General activity of each individual animal was recorded every 10 minutes Vocalizations by each individual were counted during a 2-minute period, every 10 minutes RESULTS Both groups behaved the same during the baseline period. The only behavioural changes seen in pairs when prevented from nursing was a slight increase in calling rate and walking by the TWO-STEP group; 2% above baseline (Fig. 6A, 6B). Behaviour of TWO-STEP pairs was only altered slightly by mother-young separation, which was dramatically different than the response of CONTROL cattle weaned the traditional way (Fig. 6A, 6B, 7A, 7B, 7C). CONCLUSIONS Calves reacted very little when milk was taken away and surprisingly little when subsequently removed from their mother. Two-step weaning dramatically reduced the behavioural changes associated with weaning distress in both cows and calves. Traditional methods unnecessarily exacerbate the weaning stress experienced by cows and calves and the two-step procedure reduces weaning stress in beef cattle. QUESTION Is stress at weaning the result of calves missing the milk or the mother or both? Fig.1 At weaning, vocalizations increase dramatically for 4-6 days. ACKNOWLEDGEMENTS Funding for this research was provided by the Saskatchewan Agricultural Development Fund. Thanks to Dr. Jon Watts and Jean Clavelle for their help with observations. Fig. 2. Anti-sucking device used. Fig. 3. Device fitted on a calf. Fig. 4. Nursing was prevented. Fig. 5. Calves were still able to graze and be with their mother. MATERIALS & METHODS 16 cow-calf pairs Two-step calves wore an anti-sucking device (Fig. 2, Fig. 3), which prevented nursing (Fig. 4) but still allowed them to graze (Fig.5). 8 CONTROLtraditionally weaned (see INTRODUCTION) 8 TWO-STEP nursing prevented for 4 days while pairs were still together [step 1] then cow-calf separation [step 2] Fig. 7C. Mean (±SEM) distance walked by calves on each of the first 4 days after being separated from their mother. DISTANCE WALKED (km) DAYS POST WEANING Fig. 6A and 6B. Mean (±SEM) daily number of vocalizations given by cows and calves based on recorded observations. NUMBER OF VOCALIZATIONS DAYS OF EACH PERIOD BASELINE all calves nursing NO MILK half calves nursing half calves no milk SEPARATE cow and calf pairs apart Fig. 6A - COWS DAYS OF EACH PERIOD BASELINE all calves nursing NO MILK half calves nursing half calves no milk SEPARATE cow and calf pairs apart Fig. 6B - CALVES TWO-STEP cattle called 85% less (Fig 6A, 6B), walked 80% less (Fig. 7A, 7B, 7C) and calves spent 25% more time eating (8A, 8B). Fig. 7A - COWS TIME SPENT WALKING (min) Fig. 7A and 7B. Mean (±SEM) time spent walking per day. DAYS OF EACH PERIOD BASELINE all calves nursing NO MILK half calves nursing half calves no milk SEPARATE cow and calf pairs apart Fig. 7A - COWS DAYS OF EACH PERIOD BASELINE all calves nursing NO MILK half calves nursing half calves no milk SEPARATE cow and calf pairs apart Fig. 7B - CALVES Fig. 8B - CALVESFig. 8A - COWS TIME SPENT EATING (min) Fig. 8A and 8B. Mean (±SEM) time spent eating per day, after separation DAYS POST WEANING DAYS POST WEANING STATISTICS Overall treatment effects within each period were analyzed using the Mann-Whitney U test statistic. NSP < 0.01 NSP < 0.01 NS P < 0.03NS