A year from now, Pennsylvania's commercial dog breeding kennels will face tough new rules regarding the treatment of the animals they house.

Aimed at changing Pennsylvania's reputation for "puppy mills,'' the new regulations govern temperature, ventilation, humidity, lighting and flooring in kennels that breed dogs for sale to dealers or pet stores or that sell more than 60 dogs during a year.

The regulations mandate that kennels be adequately ventilated, that excessive humidity levels be reduced and that temperatures be continuously monitored throughout the day.

But one part of the rules - which run 873 pages - remains particularly controversial. This is language that allows puppies and their mothers (for a limited time) to reside in cages in which the flooring is comprised of wire mesh.

Mesh flooring allows animal waste to pass through and makes cleaning easier for kennel operators. However, this flooring is very hard on animal paws and can result in abrasions and splayed feet.

Mesh flooring is generally banned by the new kennel regulations, but this exception has attracted the concern of animal rights organizations and some lawmakers.

Even the state's Independent Regulatory Review Commission, which has final say on all new state regulations, noted the contradiction in the mesh flooring exception.

In approving the kennel regulations, the commission said there was an "oversight'' in the law regarding mesh flooring and called on lawmakers to amend the measure to ban it entirely.

We agree. We would urge the Legislature to address this situation immediately so that kennel operators will have time to comply before the regulations take effect on July 1, 2011.

Kennel operators complain that the new rules are unnecessarily costly. However, the state's tough new approach to dog breeding was a response to horrific conditions in some kennels, a number of which operated outside earlier regulations.

Already, new requirements for licensing, veterinary care and now the specter of rules on temperature, ventilation, humidity and lighting have led to the demise of about two-thirds of the commercial kennels in the state. About 100 of these large kennels now remain.

The state has a responsibility to make sure those that remain comply with all the new rules and lawmakers and regulators must make sure that this includes a complete ban on mesh flooring.