Apparently Jason has a cancer of the esophagus From The Big Cats facebook page:
Hey there friends, sad to say but the Big Cats have to step aside and miss our annual holiday show this year. A few weeks ago Jason found out that his two month long sore throat was in fact a bit of cancer growing on his esophagus. The good news is that it's localized and very much treatable. He gets started later this week. Thanks in advance for keeping him in your thoughts. We'll see ya in 2015.