This week's hot weather has forced the Irish Greyhound Board to cancel some events.
All trials have been suspended for the rest of the day, while this evening's races in Longford has been called off.
Tonight's cards at Enniscorthy and Youghal will proceed as planned.
They are monitoring all race meetings subject to changing weather patterns and local conditions throughout the week.
A spokesperson for the IGB commented: "To cancel trials or racing can be a great inconvenience to owners and our customers but the welfare of greyhounds comes first in all operational decisions.
"Staff at all tracks have been advised to supplement existing operational arrangements during this heatwave to ensure welfare considerations are fully taken into account."