All horses and racegoers at the Fairyhouse racecourse, Co Meath, are to be disinfected in a bid by the Government to avert the threat of foot-and-mouth disease.
In addition, all livestock markets near the border with Northern Ireland are to be stopped until further notice.
Hunting has also been banned throughout the country, along with other farming and agri-sporting events.
Meanwhile, 30 crossings along the 240-mile-long border are being manned by police and troops enforcing an existing ban on all livestock, meat and dairy products imports from the UK, including Northern Ireland.
There have been no cases of foot-and-mouth in Ireland since 1941.
The extended set of measures announced by Agriculture Minister Joe Walsh aims to prevent the recent British outbreak of the disease reaching the republic.