I'm a bit of a jokester at work. I enjoy sarcasm and literalism and will crack jokes whenever I can. One of my favorite tricks is to scare the easily frightened among my staff, especially my office manager who startles rather easily. Sometimes I'll use odd accents just for the fun of it or will dance in a silly manner. I enjoy making people laugh and keeping the mood light.
This humor extends to my clients when I can. I've worn bunny ears at Easter and a dog-head visor hat during the summer. If I can make a client smile I consider myself successful.
I also enjoy self-deprecating humor and am not afraid to make fun of myself. Among staff I don't care that they always call me "Dr. Bern", and will sometimes pick up nicknames like "Bernie" or "Bernster". I readily acknowledge when someone gets me with a joke or witty comment and admire their ability.
I work in a profession that can be depressing and heart-wrenching. Every day I see sick and injured pets. Death happens every week. I routinely see owners neglect their pets and refuse necessary treatment. This can be a very emotionally draining job if you stop and think about the hardships and challenges. Burnout is high in veterinary medicine due to long days and nights of dealing with illness and getting few breaks.
That's why I value humor.
When the day wears on you it helps to inject some humor into the situation. This is actually common in other professions that face similar emotional roller-coasters and life-or-death events. I have a good friend who is a paramedic and he says they also have a sort of gallows humor. It's a coping mechanism that allows us to deal with things that sometimes make us want to spiral into depression.
I have found that it's a good idea not to take myself too seriously. It keeps me honest and humble. It also allows me to lead my team by being willing to be the butt of a joke, thus allowing them to laugh.
It's also just fun.