MOUNT LAUREL, N.J. – More than 23,000 pet owners in the United States have asked for money from a $24 million settlement for owners of dogs and cats who were sickened or died after eating pet food contaminated with an industrial chemical.

U.S. pet owners with claims were set to start receiving checks sometime in 2009, but their payments could be held up even longer while a judge sorts out last-minute appeals to the settlement filed by four people.

The legal snag pits lawyers against lawyers in a complex and emotionally fraught case.

"If one of their objections succeeds, the class comes unraveled," said Kenneth A. Wexler, a Chicago lawyer involved in working out a settlement.

The case began in March 2007, when dogs and cats mysteriously started getting sick. It turned out that the common thread was pet food produced under nearly 200 labels – much of it by the Menu Foods Income Fund in Streetsville, Ontario.

Most of the food contained Chinese-made wheat gluten laced with melamine, an industrial chemical used to make plastics and fertilizers.

Menu Foods other companies involved in making, distributing and selling the food, agreed to pay pet owners up to $24 million in a deal approved by a judge in October.

The settlement also includes Canadian pet owners, who have until Jan. 27 to file claims.

While the settlement does not compensate owners for pain and suffering associated with the death or illness of their pets, it was structured to pay up to 100 percent for a variety of other costs – from vet bills to replacing carpet ruined by sick pets.

Pet owners can get up to $900 for undocumented claims – for example, if they didn't save receipts that showed they bought the contaminated pet food.

A claims administrator will review the claims. If those that are approved add up to more than the amount available to pet owners, the payout to each owner will be reduced. It's not clear yet how long it might take to determine whether the awards would be reduced.

Plaintiffs lawyers have requested more than $6 million from the settlement.

Four pet owners are appealing the case for a variety of reasons.

Two California pet owners say the settlement does not address their concern that the contaminated food was labeled "Made in the USA" though it contained products from China.

Attorney Jeffrey L. Weinstein from Athens, Texas, who is representing two other people, said class action settlements are often rushed through.

"There's this wink-wink agreement, where all of the sudden, everybody's so happy there's this resolution," Weinstein said. "In most of these scenarios, the class members get little or no true value."

In legal filings, plaintiffs lawyers called Weinstein "a professional objector" to class-action settlements who uses the same boilerplate objections repeatedly and said Weinstein's efforts were aimed at helping himself, not the pet owners.

Lawyers for the plaintiffs have asked a judge to make the objectors post bonds – $12,500 combined for the California pet owners, and $192,500 for Weinstein's clients – to assure they're serious about their claims before the objections can move ahead.

The judge has asked for legal briefs to help him work through the bond request.