Berlin polar bear Knut died of excessive brain fluid

Mar 30, 2011, 15:52 GMT

Berlin - Knut, the Berlin Zoo polar bear who became an international celebrity before dying earlier this month aged just 4, died of an excess of brain fluid, not stress, according to sources quoting an post-mortem report Wednesday.

Cerebrospinal fluid fills the cavities of the mammal brain. An abnormal build-up of fluid can expand the cavities, known as cerebral ventricles, causing fits and death.

Knut died without warning March 19, slumping lifeless into his pond as horrified visitors watched.

Animal lovers around the globe have offered varying theories on his demise. Some demanded the zoo's closure, accusing it of hounded Knut to death by penning him up with three bossy older female bears.

But the pathology report, to be delivered to the zoo Thursday, says Knut, was already ill.

The sources told the German Press Agency dpa that an autopsy at the Leibniz Institute for Zoo and Wild Animal Research checked Knut's adrenal glands but found no signs of stress.

Nor did he have epilepsy, or a genetic defect caused by incest, but instead had developed a fatal brain disease.

Doctors said that once the fit happened, nothing could have saved Knut. Some water entered his lungs, but was not the cause of death. Even if he had remained on his rock, he would have died within seconds.

Bernhard Blaszkiewitz declined to say when he would hold a news conference to officially release the findings.

Knut was hand-reared by his keeper after his mother rejected him.

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