Dietary strategies for amelioration of heat load in feedlot cattle

Summary

The proposition was examined that feeding management and ration formulation can lead to amelioration of body heat load in feedlot cattle exposed to high environmental heat load. From the available literature, it was concluded that changes in diet formulation by itself, for instance by inclusion of rumen-inert lipid or slowly-digesting grain, were less likely to lead to significant heat load amelioration than a strategy which combined dietary changes with changes in feeding time.

This would allow a match between the period of peak heat production and the cooler night period. Knowledge required for assessment and implementation of this strategy was identified. A key component of the assessment would be investigation of the utility to predict heat production from cattle, using an existing Australian database of rates of grain fermentation. The anticipated outcome would be to provide a tool to reduce mortalities and production losses in the feedlot industry during heat waves.