Newly aggressive older dog

[Bripark89]

Hey everyone. I have a 5 year old harlequin rescue, named Hank. H is sweet as pie. We had him neutered about 8 months ago.

Over the past 3 months he has be come extremely aggressive when he is out in the yard by himself. He’s on an invisible fence. We’ve had 2 instances where people (women he has met and been affectionate with in the past) have come in the yard and he has lunged and snapped at.

Hank also went after the neighbor who was walking in the driveway on the other side of the invisible fence (the battery on his collar had died and Hank went through).

I’ve heard about the thyroid issues, and have an appointment to have a blood test done next week. He doesn’t show any signs of pain. Could it have anything to do with the neutering?

thanks in advance,
brian

[kahluadanes]

Not likely due to the neuter.. I would get a complete blood panel done including thyroid and lyme disease as well as other tick borne diseases..evens of pain I would still get it checked out... dogs can be very stoic.