male chocolate lab 5 years old

Question
I have a male lab named Ditka.  He is your typical all American family pet who is and always has been very patient with my kids (7 and 4) we've had him since he was a puppy.  The only time he ever showed aggressive behavior was toward me when I was about to spank one of the kids.  HOWEVER, it would always be a "warning" type of aggression in that he would bark and bite my arm but very little pressure.  As of about the last 6 or so months, he has suddenly developed an aggression toward females but ONLY when they are leaving my house.  Literally when any female young or old gets up to leave my house, he starts barking and then he grabs one of his toys and thrashes it (the way dogs do when you play tug O' war).  If we don't watch him and yell at him to get back and sometimes get between them, he puts the toy down suddenly and makes a move toward the person.  He has nipped 3 people now and this latest one is a full fledged bite in the back of the calf that may require stitches.  I have no idea where this behavior comes from.  On one occasion, he got out the front door once and my neighbor was out there and he ran after him so my neighbor had to jump into the bed of his truck but he caught his leg.  I don't know what to do at this point.  Any clues???

Answer
Hi Donovan,

Chasing females back ends out the door is aggression with no confidence. It's the old moray eel "AND STAY AWAY" routine. It's great that he targets the toy but bad that he chooses to drop it and come after them. Rather than using it to alleviate tension, he seems to be using it to build himself up.

My suggestion is to have someone knowledgable in aggression come out and work with you one on one. It could be a lot ofthings and none are appropriate to speculate about online in an email format.
Try www.ccpdt.org make sure that are familiar with aggression and should be able to come up with a plan of attack after an assessment, not on the phone and not until they actually see Ditka.

You may also want to get him to the vet for a wellness check. But I would find someone to work with you first and defer to their judgement about whether or not he needs to go to the vet.

Lastly, Absolutley manage him better around strangers until you have a better understanding of what is going on. Do not let him rehearse this stuff even one more time. He appears to be getting bolder very quickly.

Please let me know how things go.