MADISON, Wis. — Gov. Scott Walker directed state agencies Wednesday to develop emergency regulations requiring captive deer farms to upgrade fencing and restricting deer movement in an effort to slow the spread of chronic wasting disease, saying it's time to get more aggressive in the fight against the fatal deer brain ailment.

State officials have been struggling to find an effective strategy against CWD since it was discovered in Wisconsin 16 years ago. Democrats have criticized Walker for adopting a largely hands-off strategy centered on monitoring and research. They say the governor has allowed the disease to expand unchecked.

According to the Department of Natural Resources' website, 25 counties have confirmed a CWD-positive wild deer and 12 counties have seen a captive deer test positive. Last month Oneida County recorded a CWD-positive deer, signaling the disease is spreading north from its core infection area in south-central Wisconsin. The news comes just as Walker is ramping up his re-election campaign.

"It's just clear to us that we need to do more," Walker said. "We want to show those who hunt here and those we're trying to attract to hunt here that we're doing all the right things to combat chronic wasting disease."

The governor ordered the state Department of Agriculture, Trade and Consumer Protection to develop an emergency rule requiring deer farmers to do one of three things: install a second 8-foot-tall fence, install an electric fence or install an impermeable physical barrier. Deer farms currently must have a single 8-foot fence.

The proposal mirrors a bill Democratic state Reps. Dana Wachs and Nick Milroy introduced last summer. That measure would have required deer farms with CWD positives to install double fencing or electric fencing.

The bill went nowhere in the Republican-controlled Legislature. But Walker has adopted a number of other Democratic initiatives as his own this year, including removing offenders from the state's troubled youth prison, guaranteeing insurance coverage for people with pre-existing conditions and pumping up school funding.

"Now he's pulling the fire alarm?" said Wachs, one of more than a dozen Democrats running against the governor this fall. "He ignores this problem until it's a raging epidemic. It was not difficult to predict (CWD) would spread."

Walker acknowledged taking ideas from the bill. But he stressed the rule goes further, requiring farms statewide to upgrade fencing rather than just farms with CWD-positives.

Deer farmers have balked at the cost of enhanced fencing. Richard Vojtik, president of the Whitetails of Wisconsin Association, which represents game farms, has complained that double-fencing would cost farms millions of dollars without guaranteeing disease containment. Vojtik didn't immediately return a telephone message Wednesday.

Walker also ordered DATCP to develop an emergency rule banning the movement of live deer from deer farms in CWD-affected counties, defined by the DNR as counties with a positive as well as counties within 10 miles of an infection.

He directed the DNR to ban movement of whole deer carcasses from CWD-affected counties unless the carcasses are headed to a taxidermist or meat processor. Hunters could still quarter the deer within the county where it was killed and take the meat anywhere in the state but no portion of the spinal cord could be attached or moved. Scientists have discovered prions, the pathogenic agent that causes CWD, in the spinal fluid of infected animals.

Walker said he wants the rules in place in time for the fall hunting seasons.

CWD attacks the brains of deer. Infected animals grow thin, act strangely and eventually die. It was discovered in Wisconsin near Mount Horeb in 2002. The finding sent shockwaves through the state's $1 billion hunting industry.