Sudden guarding aggression
We have a huge problem with my 19 week old that just came out of nowhere. Yesterday while my husband was flirting with her, they took a break and he put the flirt down and went to handle her. We practice handling her multiple times a day (let me see your teeth, your ears, your eyes, your paws, etc). She growled and snapped at him in a way that suggested she was guarding the flirt. We thought it might be an isolated incident because she doesn't want to be handled when she's in prey drive mode, which makes some sense.
She got LOTS of exercise last night and this morning we got up and went out as usual. My husband took her for a walk and it went great. Then he fed her in her crate. We do it exactly the same way all the time. We prepare her food in one bowl and then dole it out in portions in another bowl while she's in her crate. So she sits and waits for us to prepare it, then she settles in the crate, then she gets the food. When the bowl is empty, we take it out (she stays in the crate), put more in, and give it back to her. We have always done this and she's always been perfectly fine. But this morning, she guarded her bowl, even when it was empty and he was putting more in. She barked and actually bit his hand and drew blood. I went in to finish feeding her and she was fine when I gave her her food, but when I went to take the bowl away, she barked and snapped at me. She's obviously resource guarding, but why now? We've been taking her to puppy training and working with her constantly. We exercise her and love on her and she's really been coming along with obeying us more and biting less. But this new behavior out of nowhere is terrifying. She's 45 pounds already and will obviously only get bigger. I know there are things we can work on with guarding, but it worries me that we had already firmly established with her that us being around while she's eating is a GOOD thing. We take the bowl, she gets more food.
We're both in tears because we feel like we already give every single minute of our time and effort to this dog. We work full time and we walk her every morning, come home and interact with her every lunch, and exercise and play with her every night for all of the time we have. She's always been on the verge of being "too much dog" for us, but I've always said that if it's just a matter of us trying harder, we'll keep trying harder. She's SO good and SO sweet and we love her SO much. But I don't know how much MORE work we can do.
I know that guarding is a fairly common issue, but does anyone know why it would come out of nowhere like this? And what we can do about it?