Just wondered whether anyone had this problem. In all my litters never experienced this.
There were 5 in the litter and all was fine until they were about 6 weeks when I had some infighting. Some of it quite bad. I suddenly became aware that that they were running around the rear ends of some of the puppies before going into attack mode. \i then had a light bulb moment and checked glands which were full. Leading up to this their poos had been a bit soft which I was putting down to Mum's milk as the food they were on should have produced firm stools indeed as they are now.
After this they were a little better within the pack although not perfect. I am guessing the smell may have led them to think they were foreigners in the pack.
Now I have kept 2 girls from the litter. They are fine together and their stools very firm now but I put them up to groom and look at them to-day and thought I would check and low and behold one out of the 2 needed doing. Anyone experienced this before as obviously I am hoping they will be like any other of the breed I own and never have a gland problem.

Sorry should have said they are 10 weeks old tomorrow.

All I can say is that when I started working as a vet nurse and learnt to empty anal glands, I obsessed about them and emptied my puppy's, and that was a huge mistake as they ended up being too slack due to being manipulated too often at a young age and he had problems for life. I would never touch anal glands in a pup unless there were obvious problems/discomfort -they can be full without there being a problem.

Ok
Understand but had a real problem with fighting which eased after they were done so felt I had no choice.
They were laying into the smallest puppy like nothing I have ever seen before. It was obvious it was the rear end that was causing great interest.
I have never ever done that before in fact never even thought about them in puppies or my older dogs.
I wondered whether this would be ongoing or now they are pooing solid, the problem is likely to go away.

I agree with Goldmali anal glands should not be routinely emptied, diet plays a big part and with a good diet they should empty naturally.
This article explains better than I could ever do.
http://dr-dobias-natural-healing.myshopify.com/blogs/blog/11014181-holistic-approach-to-anal-gland-problems-in-dogs

I am a very experienced dog person and am well aware of the problems of doing this routinely.
Everything is now normal stools wise but at the time they were not as I have had before with a young litter.
I only wondered whether the obsession with rear ends ( which I now believe was glands) had led to fighting/attacking
I have never, ever experienced this situation before.

I so agree about not routinely manually emptying these glands (which are meant to fill again btw).   The more you mess around back there, the more you may actually need to!    I have had the occasional puppy who started to 'bulge' making me investigate however.   Fact is unless these glands become impacted, and perhaps infected, they shouldn't need touching - and I'd never allow a groomer to do this.   If I have a problem (adults) I get my vet to do the job so they can see what comes out and whether it needs treating.

Whether this would be the cause for the litter not to be getting along, I have no idea, but for sure, when a bitch has a problem with these glands, it will attract the boys.

If once drained and treated, this returns, then I'd always look to the diet so the stool is kept 'normal', ie not loose.  

ps   My current Basset has had a problem with these glands, and at the time, with the vet I was using, I was told he was 'big back there' so a firm stool didn't always do what it should be doing to release a small amount of the fluid.   Whether this is true I have no idea (size back there) but for sure, although I can usually drain the glands myself, externally, I can't with him!

It may not have had anything to do with the anal glands at all Hazenaide, watching many litters I've seen such variations, some litters in-fighting does not happen at all, although you would be really lucky to not have any from 8 weeks, but, sometimes you can get characters who literally look like they are killing each other between 6-8 weeks, it's why if I see any roughuiens in a litter they tend to spend more time with me, they get even extra socialising......I know that you are experienced with dogs as you say, but you can get characters who surprise you, and litters which surprise you.

If all is well you can socialise them as you always do, but if things kick off more than what you would usually expect, then spend more time with the trouble maker and the one being picked on. You need to make sure all the litter feels confident and ready for their new homes, you can't allow the more confident to hold the others back. Some litters have too many strong or weak characters to have a good balance.

There may well be an anal gland problem, but we know it would be a bad thing to continue to self express unless blocked, so just go with one to one socialising and playing with the pups to keep their focus on yourself and new experiences to contain any problems, if they re-occur.

Although, if you are really worried about any of the pups I would advise a vet check. :-)

The pup that was being attacked has gone and I'm just left with my two.
They are fine together.