Celebrity zookeeper Jack Hanna, diagnosed with dementia, daughters say in statement

Jack Hanna, the celebrity zookeeper and TV show host, has been diagnosed with dementia which is now thought to be Alzheimer's disease, according to a statement shared on Twitter by his family.

"Doctors have diagnosed our dad, Jack Hanna, with dementia, now believed to be Alzheimer's disease. His condition has progressed much faster in the last few months than any of us could have anticipated. Sadly, Dad is no longer able to participate in public life as he used to, where people all over the world watched, learned and laughed alongside him," Hanna's daughters said in the statement about their 74-year-old father.

"Dad engaged with millions of households through his media appearances and weekly television programs — including Animal Adventures, Into the Wild and Wild Countdown. This allowed him to bring an unparalleled level of awareness to the importance of global conservation given the unrelenting pressures on the natural environment. To say that we are abundantly proud to be his daughters is an understatement," they said in the statement. 

"While Dad's health has deteriorated quickly, we can assure you that his great sense of humor continues to shine through. And yes — he still wears his khakis at home," they said.