The Howard County Council passed a sweeping rewrite of local animal control laws tonight that will require dog owners to leash their pets and double the fines for cruelty, but will not ban the use of steel leg-hold traps on wild animals.

The bill, proposed by the county's Animal Matters Hearing Board, had been widely criticized by trappers, hunters and dog fanciers who said the revisions would outlaw time-honored methods for training and trapping animals.

The council, acting at its first session to be broadcast live over local cable television, enacted amendments to answer most of the concerns without substantially altering the bill. It dropped the most controversial provision banning steel leg-hold traps, citing potential constitutional problems.

County Solicitor Timothy E. Welsh, in a legal opinion issued last Friday, concluded that only the Maryland General Assembly had the power to regulate trapping in the state. A law outlawing the traps in Baltimore County was overturned by a local court in 1980 on those grounds, Welsh noted in the opinion.

"It's as I expected. It's a matter of law. They can't do it. Nobody can, except the state legislature," said Bernard F. Serafin, Maryland director of the National Trappers Association, who lobbied against the ban.

Under the revised law, dog owners must leash their pets whenever they take them off their property, but the council, in deference to hunters and dog fanciers, exempted hunting dogs and dogs being trained from the requirement.

In another concession to hunters, the council amended the law's definition of animal cruelty to permit the use of live game to train hunting dogs.

Fines for subjecting an animal to cruelty or neglect were increased from a maximum of $500 to as much as $1,000. The council increased fines for multiple offenses under the new law.

The council also added a $50 fine for failure to stop after injuring an animal with a vehicle and made encouraging animals to fight a crime punishable by a $50 to $100 fine.