BATON ROUGE - Federal officials are putting together a report on the deaths of animals at the Baton Rouge Zoo.

Since the start of 2016, eighteen animals have died. Most recently, a juvenile Malayan tiger died. The tiger, named Hadiah, died in mid-April.

"This death was much unexpected," zoo veterinarian, Dr. Gordon Pirie, said in a WBRZ and WBRZ.com report on the death. "(earlier in the day on the date the tiger died), we were performing routine rounds with a LSU veterinary intern and she appeared to be exhibiting normal behavior and in great health."

Zoo veterinary staff were able to review the tigers' behavior from the installed camera inside the cats' den. The footage shows the tiger entering the den as usual and then resting for a short period of time before showing obvious signs of distress. She died approximately 15 minutes later.

The zoo asked the USDA to come to the facility after the tiger died. A report from the USDA is expected to be complete and released soon.

The zoo released necropsies - autopsies of animals - for each case Thursday. Multiple fish, a duck, antelope, two giraffes, primate, cheetah, two bats, a parrot, turtle, wild cat, and frog have died. In all, 18 necropsies have been conducted. Officials are still awaiting a final necropsy on the tiger. A preliminary report showed nothing conclusive.

Thursday night we spoke to Zoo Assistant Director Sam Winslow about those reports. He says both the cheetah and several were relatively old. The big cats are on long-acting birth control, and there are indications that the birth control may sometimes lead to uterine cancer. While neither the cheetah nor several had uterine cancer, both had conditions related to their reproductive or urinary systems.

The sheep died of a ruptured bladder following a kidney stone. Winslow says kidney stones in sheep aren't treatable surgically, so the medical strategy is to treat them for pain and wait to see if the stone will pass on its on. Records show the sheep was treated for its pain.

The bullfrog and fish both died of conditions typical in the wild. The box turtle was part of a colony of turtles at the zoo that have mycobacterium, which they contract in the wild. They cannot be released back into the wild, otherwise the condition will spread.

Winslow also claims most zoos don't perform necropsies following all animal deaths.

"They might just you know take them out and bury them out in the back," he told News 2. "We care about our collection...If we know how they died [we can] survey their health and see if there is anything going on so that we can better take care of animals in the future."

Coincidentally, the deaths come as the zoo announced a controversial study of its future at its north Baton Rouge location. Officials are considering a $110 million upgrade that could include moving it to a different location.

Check back for more on the necropsy data later Thursday.

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