Effects of shade provision on the behaviour, body temperature and milk production of grazing dairy cows during a New Zealand summer

Abstract

The aim of this study was to quantify the behavioural use of shade during a New Zealand summer, and to determine the effects of shade availability on body temperature and milk production. Holstein-Friesian cows were either grazed with access to shade, or grazed in an adjoining part of the field with no shade, for two 10-day periods in a cross-over design with 10 cows per treatment. Vaginal loggers recorded body temperature and video cameras recorded shade use. Cows started to use the shade when the temperature reached 25°C and shade use increased exponentially with increasing ambient temperature. Data analysis for behaviour and body temperature was restricted to 6 days on which the maximum t..