The case of two English-women who recently chose to go to jail rather than stop demonstrating against blood sports has revived yet again an old and bitter British controversy.

It is not surprising that a nation of both animal lovers and lovers of sport should find itself in internal conflict when one group derives its pleasure from slaughtering the interests of the other. But the depth of feeling and the intensity of the passions aroused lift this debate into a class of its own.

There are about 4 million blood sport enthusiasts in Britain, drawn from all social classes. Fishing attracts 3 million followers, 750,000 people shoot birds and 500,000 go fox-hunting. Others stalk stags, hunt ofters, or engage in the controversial pursuit of hare coursing, in which the speed and agility of a greyhound is matched against those of a hare. If the hare loses, it pays the penalty of a violent death.

Foxhunting, however, has always attracted the greatest obloquys; partly, one suspects, because of its ritualistic flavor, including the wearing of the hunting pink, and also because of its association with the landed gentry, a dwindling but traditionally unpopular section of society.

Until comparatively recently the foxhunting fraternity scornfully dismissed its opponents as an insignificant group of harmless fanatics unversed in the ways of the countryside. But during the last 10 years or so, some enemies of the hunt have adopted the modern style of protest and become militant and occasionally violent.

Earlier this year, at the Lakeland village of Caldbeck, the grave of John Peel, the most famous foxhunter of them all, was desecrated and a stuffed fox's head placed on the shattered headstone.

Hunt meetings have been disrupted by saboteurs blowing whistles, shouting, and in some cases spraying lacquer into the hourds' eyes. Similar tacties, including the throwing of smoke bombs, have been employed at hare courses. On several occasions, huntsmen have responded by attacking protesters, but so far no one has U.S. District Court of six real estate been seriously injured.

There are signs, however, that next season the hunters will be hounded as never before. Last May, an uncharacteristically boisterous meeting of the League Against Cruel Sports ousted its chairman of the last 15 years, Ray Rowland, and elected in his place Jan Rennison, a 30-year-old former Miss Australia and a militant opponent of cruel sports.

In the past the league, which has 15,000 members and a substantial bank balance, has condemned violent action on the ground that it is more likely to alienate public opinion than enlist support. Rennison and her followers have grown impatient of such moderation and threaten to employ more spirited tactics in the future.

The prospect of aggressive opposition finds the hunt lobby weaker than it has been for some time. Two years ago, the Royal Society for the Prevention of Cruelty to Animals broke its silence on the subject and declared that it was no longer convinced that the fox was a pest.

Even if it was, argued the society, encouraging dogs to tear an animal to pieces was barbaric, and more humane methods of controlling the fox population should be found. What was more, added the society, it was about to turn its attention to other blood sports, including shooting and angling.

All of which, given the society's royal patronage, placed the queen and her family in a slightly embarrassing position. The queen enjoys fishing for salmon on her Scottish estates, and has occasionally given financial support to hunt associations.

Her husband, the Duke of Edinburgh, is an accomplish shot who has killed countless pheasants, and on trips abroad, the occasional tiger or bear.