My in-laws have got a Jack Russel. He’s been with them on their farm for a few years now, having been passed around a few homes beforehand. We think he’s 5 or 6 years old, but can’t be sure. He’s got the loveliest temperament and is great with people and, until now, other dogs. However, recently this has changed and he has become aggressive towards other male dogs.

It started with our dog (also male, a couple of years younger), which used to spend quite a bit of time down at the farm when we were out. They had a couple of big fights, to the point of blood being drawn, so now we can’t leave our dog down there. We thought that this might be because our dog was too boisterous – he always wants to play, but can get a bit possessive over toys – but now he has started attacking their other (older) male dog. This has got to the point where they are trying to rehome him, but this would be a real shame so I was wondering if anyone had any suggestions on how to stop this aggressive behaviour.

There are a few things that may have caused the change in dynamic:
1. They also have an old female spaniel who is coming to the end of her life. She has become very aggressive towards our dog (although snarling and barking rather than fighting), but is fine with their other dogs.
2. The in-laws are now looking after our 1-year old son a couple of days a week, so there is a baby in the house. However, this hasn’t affected the dogs’ routines – if anything they get a few more walks.
3. Our dog had been spending quite a bit of time down at the farm, but this stopped after the initial aggression between them and before he started attacking their other dog.

Any thoughts/tips would be greatly appreciated – we really don’t want to see him go as he’s such a lovely dog otherwise.

I’m confused…
Your dog started attacking their older dog?
Their JR started attacking your dog?

So the JR gets the push…

Jack Russells are very loyal and protective of their “family”, which now includes an infant. Has it ever shown any aggression to the baby?

It would seem the problem is your dog, not theirs…

it reads like your dog is the problem.

Not sure how you came to that conclusion given we’ve removed our dog from the equation and their dog has started being aggressive towards their other male dog.

As for our dog starting to attack their dog? I didn’t say that, although maybe my wording was unclear. Our dog and theirs had a couple of bad fights, initiated by their dog. We thought that might be because our dog was too boisterous when they were playing together, or wanting to play too much.

Anyway, as I say, our dog no longer goes down to the farm except occasionally with us. The issue is that the Jack Russel has started attacking their own older male dog.

For clarity:

Jack Russel and our dog (miniature Schnauzer cross) started fighting
Our dog no longer goes down to the farm because of this
Jack Russel has started attacking their male (older) Welsh Terrier

I should also point out that for the last few years our dog has been getting on perfectly happily with theirs (even for extended periods when we’ve been away and our dog has stayed there), and the Jack Russel and Welsh Terrier have been perfectly happy living together.

The Jack Russel has not shown any signs of any aggression towards our baby, any people, or the old female Spaniel.

Presumably the old spaniel was top dog and the JR knew it. Now she’s old and weak the JR wants that position. THey’ll soon work it out and peace will be restored.

has he been castrated?

My sister has a wire haired terrier of some description & it sounds like a very similar thing that happened to her.

She used to have a very good temperament, but got in a couple of scraps & now is very aggressive when around other dogs – they took her to a pet behaviour expert who reckoned that the fights she’d had made her scared of other dogs, so now when she sees other dogs she goes straight into fight mode.
They tried all sorts to resolve it, but nothing has ever worked.

Not much help, but hope you have more luck in finding a solution.

All dogs have been castrated.

Sometimes he gets on fine with our dog – it’s all very unpredictable. The Jack Russel doesn’t instantly show aggression towards him and will often quite happily play with him.

However, it’s easy to solve the problem of him attacking our dog – our dog just doesn’t go there. That’s not ideal for us, but a hell of a lot better than rehoming the Jack Russel (which nobody wants to do, it is really a last resort). As I say, the real issue is the attacking of their other dog.

Thoughts are…

1. Younger JR flexing his muscles.
2. Older JR has become more protective with the addition of the child.
3. Older Spaniel likewise.

Q: did the aggression start at around the same time the child was introduced?

Well if your thinking of getting rid I would try a muzzle, don’t separate them, as soon as he gets aggressive muzzle him for 5 mins, repeat as necessary, he will learn it’s not acceptable.

Thanks dirtydog, going to give that a go.

Small dogs, especially JR, are aggressive in our experience [obvs this is a sweeping statement and not true for all JR]. Old dogs can also have a shorter fuse and more likely to have a go.

When our older dog (lakeland cross) was loosing her sight she became very aggressive to our patterdale. It was carnage we all ended up being bitten trying to separate them and had two expensive vets bills. We kept them apart and used a muzzle when out walking.
Now she is blind (cataracts) the aggression has almost gone, we don’t trust her 100% but dog owning is now a lot more relaxed.

has he been castrated?

yes, that would piss me off too.

It was carnage we all ended up being bitten trying to separate them and had two expensive vets bills

I think you went to the wrong place to get your bites sorted out 😉

Freester – Member
It was carnage we all ended up being bitten trying to separate them and had two expensive vets bills
I think you went to the wrong place to get your bites sorted out

Have you not been watching Better Call Saul, it’s the best place to go if you want to avoid the law 😉