Hi guys, after a bit of advice. I had my 4 year old dog (malamute) castrated 5 weeks ago and since then I have noticed he's been slightly grumpy with my other dogs (male and female, both castrated/spayed, toy breeds) No fights or anything like that, but they are usually very good friends and he's growled at them a few times now, when food or attention is involved. I know they say their appetite can increase etc and he is always looking for food! Would the change in him be this quick? I've not noticed changes like this in my other dogs, they were a lot younger when they were done, would that make a difference? Do you think this could be something to do with his hormones? And is it likely to stay this way?
Thanks for any advice.

Castrating any adult will change the ambiant feel of the pack, it should settle but he may well still be feeling unwell it takes on average 3 weeks to recover from anethestic and some take a good deal longer.

It may well be he was top dog and now is either being challenged or feels unable to hold his place if this is the case there may well be a period whilst the pecking order is sorted.