The jaguar that was euthanized Monday due to kidney failure clearly had suffered from the disease before his Feb. 18 capture, but the stress of the capture probably aggravated Macho B’s problems, a veterinarian who treated the cat said today.

“I’m sure kidneys were going bad for some time. Kidneys don’t go bad at the snap of a finger,” said Dr. Dean Rice, the Phoenix Zoo’s executive vice president. “All they are is filters. As we get older, they don’t filter as well.”

But the sedative that Game and Fish researchers gave the cat at the time of capture, along with other stresses associated with capture, probably took a toll on the cat, according to Rice.

“Any medications, any drugs we take, no matter whether you are human or animal . . . if you give them sedation and the kidneys are not working,” the sedative can have a negative effect, he said.

Macho B was captured inadvertently two weeks ago southwest of Tucson, during a research project aimed at capturing mountain lions and black bears, Game and Fish officials said. He seemed healthy and hardy at the time, officials said.

The cat, age 15 to 16, was the last jaguar known to be living in the wild in the United States, officials have said.

But over the past weekend the cat had slowed in its movements and reduced its foraging. He was recaptured on Monday, flown by helicopter to Phoenix and taken to the zoo where a blood test found he had advanced kidney failure.

At the time of Macho B’s death, state and federal wildlife officials had said they hoped that blood samples taken of the cat back on its Feb. 18 capture would show how serious were the kidney problems then. Kidney failure is common in aging cats, the Game and Fish Department said today in a news release.

But it turned out that the blood samples were not taken in a way so they could be used to analyze the cat’s health — only to analyze its DNA, Game and Fish said in the news release. That was the sampling method previously approved as part of a capture protocol developed by leading jaguar experts, the department said.

Now, authorities are counting on an analysis of tissue samples of the dead jaguar to provide clues to how long the cat had kidney problems. The zoo sent the samples on Tuesday to the Arizona Veterinary Diagnostic Lab at the University of Arizona in Tucson.

Some environmentalists have been critical of the department’s handling of the capture, and expressed concerns that the stress of capture could have led to his death.

Rice declined to criticize the department.

“I’m glad they collared him,” Rice said. Otherwise, “he would have just gone off and died somewhere on his own,” Rice said.

Memorial service

A memorial service for the jaguar Macho B, and a plea for better protection for his fellow jaguars, will be held from noon to 1:00 p.m. Thursday outside the offices of the U.S. Fish and Wildlife Service, 201 N. Bonita Ave., Suite 141, in Tucson.

“Macho B epitomized the majestic but fragile nature of our southwestern ecosystems. By speaking out for Macho after he is gone, we fervently hope that our mountains and deserts can still be home to his kin for decades and centuries into the future,” Michael Robinson of the Center for Biological Diversity said in a news release. The group is organizing the event.

Contact reporter Tony Davis at 806-7746 or