Fox hunts in Cos Meath, Westmeath, Wexford, Carlow and Waterford were targeted yesterday by anti-bloodsports activists.
The Fingal Harriers meet in Meath was "totally disrupted", according to Ms Bernadette Wright, of the Association of Hunt Saboteurs.
Protesters also followed the Ashbourne-based Ward Union Hunt's pursuit of captive stags that were bred especially for hunting, Ms Ward said.
Peaceful pickets by the Campaiign for the Abolition of Cruel Sports (CACS) and the Association of Hunt Saboteurs were placed on coursing in Roscommon.
"With blood sports about to be banned in Britain, the CACS will be stepping up the national campaign to rid Ireland of these cruel and barbaric pastimes," said Ms Susan O'Connor, the campaign chairwoman.
"Only legislation will resolve the cruelty issue and put an end to the merciless hounding and tearing apart of wild creatures in our countryside."
Campaign activists were concerned at the prospect of a "hunt invasion" by British bloodsports fans, eager to continue their animal abuse activities, she said.
"Already large estates have been bought by wealthy English fox-hunters, and Irish auctioneers - to their eternal discredit - are advertising in Horse and Hound and other UK hunting publications with a view to attracting Britain's elite hunting set over here."
Animal rights campaigners want the Government to outlaw hunting with hounds, "not just for the sake of our persecuted wildlife but in the interests of farmers who continue to suffer from hunt incursions". Extensive damage to crops, livestock and other farm property was caused every year by horses and hounds trespassing on farm land, Ms O'Connor said.
"Many farmers have spoken out against the hunt on local radio stations across the country, and this year has seen a record number of hunt-ban notices in the provincial press."
Garda sources said there were no confrontations at the hunting events.