Importance of outdoor shelter for cattle in temperate climates

It is well documented that health, welfare and productivity of cattle in (sub)tropical and cold regions can be improved by measures that mitigate the adverse effects of extreme climatic conditions. In temperate regions, however, the need for and effectiveness of such measures has received much less attention.The aim of this review is to give an overview of the most relevant climatic factors, animal characteristics and adaptation strategies that have to be taken into account when assessing the need for mitigating measures for cattle on pasture, more specifically in temperate areas. Belgian climatic data are used to show that conditions outside the thermo-neutral zone of certain cattle types, possibly leading to cold or heat stress and impairment of production if persistent, occasionally occur even in temperate climates. Such thermal stress is likely to become more common in the future, due to global warming and cattle's decreased capacity for thermoregulation caused by selection for high productivity. Recent research is reviewed to show that the traditional climatic indices and threshold values of the associated heat stress risk classes are outdated, too strongly focused on hot climates, and too general to evaluate heat stress in the different (mainly high-producing) cattle types bred in temperate areas nowadays. Nonetheless, the (currently limited) knowledge on the effect of adverse weather on pastured cattle in temperate climates suggests that providing shelter will benefit their welfare and productivity. Further research is needed, however, to estimate the effectiveness of different types of shelter for different types of cattle (for instance those differing in age, breed, experience and productivity).