BACK TO QUEBEC CITY 2002 TITLES
A novel protocol to assess
methods of reducing riding behaviour in feedlot cattle
K.S. Schwartzkoph-Genswein1,
J.P. Kastelic2, T.A. McAllister2, R.D. Wilde2, R. Silasi1 and D. Milligan3
1,3Alberta Agriculture,
Food and Rural Development, 1Lethbridge,Canada; 3Red Deer, Canada; 2Agriculture
and Agri-Food Canada,
Lethbridge, Canada
Strategies for reducing riding behaviour among feedlot cattle are often sought, but assessing their effectiveness is difficult. A novel protocol for assessing such strategies was tested using 60 crossbred heifers (423.1 ? 2.8 kg BW) to determine the effects of access to a cattle brush (BRUSH) vs no brush (CONT) on riding behaviour, feeding patterns and growth. Heifers were housed in four pens equipped with electronic bunk attendance monitors and two were also equipped with a brush. Heifers had ad libitum access to a diet comprising (as fed) 80 % barley grain 15% barley silage and 5% supplement, and were weighed at 21-d intervals. Melengestrol acetate (MGA) was provided in the supplement (0.5 mg/head/d) for the first 21 d and from d 42 to 63. On d 0, 35 and 49, heifers were injected (IM) with 0.5 mg cloprostenol to induce luteal regression. This protocol was designed to induce three distinct periods of mounting activity. Mounting was monitored electronically and brush use by video surveillance (two 24-h periods per wk per pen). Mounting peaked on d 26-31, 37-39 and 67-69; at those times, heifers averaged 28.3 mounts/d lasting 3.4 s. Mount frequency and duration did not differ between treatments either overall (P < 0.11) or during peak periods (P < 0.17). Heifers in the BRUSH pens attended the feedbunk more frequently (15.3 vs 10.2 visits/d) and spent more time there (169.6 vs 141.5 min/d) than did the CONT heifers (P < 0.01). However, DM intake (9.54 vs 9.09 kg/d), rate of gain (1.25 vs 1.17 kg/d), and final weights (528 vs 521 kg) were higher (P < 0.01) in CONT than in BRUSH heifers. Feed:gain ratios (6.8 vs 7.1) did not differ (P > 0.05) between treatments. Correlation between mounting frequency and average daily gain was poor (r = 0.07) . Access to a brush did not reduce riding behaviour or improve performance over an 85-d period. The effect of MGA withdrawal and strategic administration of cloprostenol reliably synchronized riding behaviour providing an effective means of testing strategies to discourage mounting behaviour.