Welfare assessment of cattle cleaning techniques

Summary

To conduct a welfare assessment of the Rockdale Dedag Machine (RDDM) relative to other beef industry cattle cleaning practiCes for support of the process and later defence of its use by industry if required, and to aid in interpretation of meat quality issues resulting from cattle cleaning techniques should they occur. One hundred and ten steers, 45 of which were pre-shorn, of similar Bos taurus genotype were studied.

The cattle were part of the 200 steers (90 pre-shorn) in the overall cattle cleaning study coordinated by Agriculture Victoria. Approximately 9 weeks later, preshorn and unshorn animals underwent cleaning using either the RDDM, shearing or washing procedures. Control animals were managed in a similar manner to the RDDM and shearing procedures but were not cleaned. The day following cleaning the groups were handled using the same facilities as on the previous day, but without cleaning, to enable an assessment of residual psychological effects to be made. Stress resulting from the procedures was assessed using plasma cortisol concentration and various behavioural indices. The RDDM did not elevate plasma cortisol or result in residual psychological stress beyond levels associated with other procedures involving similar handling of animals.

However, plasma cortisol levels associated with RDDM, shearing and control groups were high compared to other cattle handling studies, indicative that the general handling procedure employed for these groups was stressful and, in likelihood, handling practices stressed the animals more than the cleaning procedures per se. Cortisol levels were far lower after the more chronic washing procedure than after the more acute RDDM, shearing and control procedures. Pre-shearing resulted in lower cortisol levels compared to animals which were not pre-shorn, although this result appears to have been confounded by residual effects of drafting just prior to the welfare assessment.

The RDDM be considered as a viable option for cleaning cattle as it does not stress cattle beyond levels associated with usual husbandry practices. Handling practices associated with the RDDM be designed and conducted to minimise stress.A further investigation to assess the extent to which animals are stressed during washing procedures and effects of washing in differing climatic conditions on cattle welfare be conducted.