Fennell, S., Wright, D., Beneke, G. and Young, B.

Effects of shade and feed quality on feed intake, water consumption, rectal temperature, respiration rate, heart rate, plasma protein and blood hematocrit were measured in growing Hereford heifers during the summer. Heifers that were fed a high energy grain diet and exposed to the sun had higher heat loads during the hotter part of the day. Plasma volume was unaffected by the treatments. Heifers on all treatments coped well with the heat load by utilising panting and changes in body temperature to compensate for the increased heat load from solar radiation and ingestion of grain. Heart rate was mainly affected by feed quality and not by solar radiation.

Part of the Advances in Pharmacological Sciences book series (APS)