Dog getting obsessive over sticks

[VintageGardenia]

We have a 2.5-yr-old chocolate labrador who has always been very bouncy and full of energy but quite obedient (recall, sit, wait, on your bed) and quite submissive to e.g. our other dog / us / dogs we meet etc.

Over the last couple of weeks she seems to have gone bonkers over sticks. She picks up massive ones and runs around with them (walloping you on the bum as she races past) and will not give them up. Today, for e.g., I tried to wrestle one from her (probably not a good idea) and she slavered and her head went all trembly as she ground it between her jaws ifyswim. I couldn't "win", didn't particularly want to engage in a wrestling match (she is far stronger! but anyway I had ds2 in a backpack) and had to walk away and find another stick to distract her with / throw for her. But when I picked up the massive branch we'd been fighting over she leapt on it & pulled it out of my arms.

I know it may seem a trivial thing in a normally ok dog but as I usually have ds2 with me (he is 17 months) when I am walking the dogs I need them to be predictable and not to have the possibility of him having his eyes ripped out by a maniac branch-carrier.

Any ideas how I can sort her out?

I've nearly had my shins taken out a couple of times by dogs carrying overambitious sticks so you have my sympathy!

Does she maybe have a ball which she's fond of which she can carry around instead?

We have a ball flicker thing (dp says I have to stop using that term) you know those plastic arm things which let you fire a ball the length of a rugby pitch, and it is fantastic but she sometimes gets a bit antsy about it as well. I am worried she has some ishoo which I am not spotting.

Is she spayed?

Yes she is.

I'd have her checked out by the vet anyway - it's always the first port of call, especially with a sudden change in behaviour.

I actually hadn't considered the vet. We have had two other dogs staying with us for the past few weeks - I wondered whether it might be stress or something related.

Are the other dogs sharing/stealing her toys at the house? If so she could be turning a little bit possessive over things. We've got an eight month old pup and our older dog loves her to bits, but she still gets a bit iffy over her favourite toys if the pup is nearby (she usually buries them under the sofa cushion so they're safe ).

As we have two dogs normally, they do share each other's toys quite readily. I think perhaps the other dogs might have unsettled her a bit - one belongs to my mum & is allowed to sit on the sofa, go upstairs, etc, which she is not. (The labrador, that is - I usually let my mum do what she wants...)

Sticks are not good toys for dogs and you really need to discourage her having them. I have seen too many horrible injuries from dogs running onto sticks, both in the mouth and where they literally run onto them . Try taking a rope or rubber type toy with you that she prefers to hold and make that part of her exercise instead. If she picks up a stick then get her distracted with the favourite toy and she will hopefully just drop the stick.
If she likes a ball please make sure it is big enough not to be swallowed - also when they choke to death on them.