About 6 months ago Shady had the odd episode on a lead walk where she would suddenly drop her head and go as slow as a snail and look like she was slightly lame on her near fore leg. I would stop for a few seconds and give her a fuss (she looked like she was exhausted) and then she would set off normally again.
It could happen just 2mins into the walk or 20 mins into it. There was also some days she refused her breakfast (very unlike her) but it didn't seem to tie in with this strange happenning on her lead walks.
Now it is getting more frequent and happens at least once on most of her lead walks but not everyone. She is also refusing breakfast every morning but eating fairly normally the rest of the day.
When I take her over the field for a run off lead she seems fine, although now the warmer weather is here she does a couple of chases of the frisbee then lays in the cool grass for a while but I class that as normal as its still warm in the evenings when I take her.
I can't put my finger on what could cause it. Its like she has just walked 50 miles and can't take another step. I have also noticed she is much quieter in the mornings when she gets up and just comes down goes to the loo and then lays back down to sleep.
I havn't taken her to the vet as there is nothing to see and in the vets she would be acting quite normally and spending so much time there with Milo I don't want to seem like a paronoid mum.
Anyone else ever had anything like this? Or got any ideas?
Shady is just 4yrs old and a Rottie x GSD.

I think I'd like to get her heart listened to. It's probably totally irrelevant, but I know from experience that a mild arrhythmia can cause sudden tiredness that wears off once the heart's got over its skipped beat.

Thankyou for your quick reply.  I have just looked up what you said and it does sound as if it could be.  Its rather worried me now so I have made her an appointment with the vet at 8am tomorrow morning.
I have also always noticed when we play frisbee she starts to cough a bit after a couple of throws.  She has done this for at least a couple of years now, but I have always thought it was just her.
Just now I also noticed when she got up from laying position she stopped for a second and looked a little unsteady almost as though she was weak and dizzy. (I'm watching her like a hawk now LOL.).
I have booked her field for her tonight to go and have a game of frisbee in.  I will still take her as again I have noticed lately although she tires extremely quickly unlike a year or so ago she won't drop it for me to throw again until she feels ready and able and will just walk off uner a tree and lay down where its cool, so hopefully won't overdo it.
Out on lead walks when it happens I must admit I have been worried she is about to collapse and how I would carry a dog weighing over 40kg I just don't know.

I hope she'll be fine. I have the condition myself, which is why the symptoms seemed familiar! But I'm fine and on no medication.

Heart or even the hips with the crosses involved.

Heart or even the hips with the crosses involved

Not her hips I am pratically certain as because of her crosses I had her hips x-rayed by a good orthopedic vet when she was a year old and he said her hips were as near perfect as you would get in any dog and should never cause her a problem.

I would have her thyroid levels checked, this happened on and off with my rottie girl 18 months ago, once me and my OH were out walking and she suddenly just could take another step. a ran all the way home to get the car and when i got back she was walking again albeit slowly, this happened a few times and so i questioned her thyroid. She was diagnosed hypothyroid and has been on meds since and is a new dog.
Hopefully it is this as apposed to the heart as the meds for her thyroid will reverse all her symptoms.

My girls symptoms were tiredness and weakness along with continual weight gain

I would have her thyroid levels checked, this happened on and off with my rottie girl 18 months ago, once me and my OH were out walking and she suddenly just could take another step. a ran all the way home to get the car and when i got back she was walking again albeit slowly, this happened a few times and so i questioned her thyroid. She was diagnosed hypothyroid and has been on meds since and is a new dog.
Hopefully it is this as apposed to the heart as the meds for her thyroid will reverse all her symptoms.

My girls symptoms were tiredness and weakness along with continual weight gain

She doesn't have any weight gain and is not overweight at all.  But she is quite a nervy nuerotic dog that gets stressed over everything.
Also when we are out walking and she has one of these episodes usually within a minute she has recovered and back to walking fine on lead again.  Its only when we get up she seems quieter than normal for a couple of hours.
Off lead its hard to judge as she doesn't have the episodes of head hanging and look of general weakness, but I would expect her to be able to run for longer at 4 years old than just a couple of chases after the frisbee before panting heavily she finds a cool spot to lay and rest.  I know she is a big heavy dog but I would still expect her to be able to run more.

I have taken her to the big field I hire this evening and she managed 2 throws of the frisbee before she went and laid down really panting hard.  No sign of any lameness just couldn't manage anymore for a while.  She spent most of the time laying down huffing and puffing and of the 30 mins we were there managed about 8 or 9 throws on the frisbee.
Definetly doesn't seem normal for a 4 yr old dog.  I'm sure she should manage more than that.

Just reading your post and i have just posted about one of my dogs re possible heart tests...sound similar symptoms.That is how i feel about Tanna.  

Bev I can't add any more than the previous folk, but do hope that you get it sorted.  You must be beside yourself.  As if you hadn't had enough with Milo.  Fingers crossed here for you.  :-)

They don't have to be under or overweight for thyroid problems either.  Would get the heart tested first though.

I'm back from the vets.  He checked her heart and said she had a good rate of 70 beats per minute, which showed she was very fit too.
He ran full bloods and I waited for the results and they all come back normal.  He has taken her in to do a chest x-ray to see if there was a problem there as she coughs when she runs and exerts herself a lot. I will collect her tonight when i take the guinea pig in (don't ask LOL).
He said otherwise it is really waiting and seeing if anything else happens over the next few months that could give more clues or it could be neurological in which case she could be referred for an MRI scan.
I don't think I want to go as far as the MRI scan yet, will wait and see if the x-ray shows anything although I am certain it won't, but that will be another thing ruled out and then see how she goes for a bit.
I will mention Thyroid to him when I go back tonight as i forgot about that and see what he says.
Thanks for all you good wishes.
Will update again tonight.

Oh Bev, if its not one thing its another with your dogs, don't know how you keep going with it all. Fingers crossed for some good luck to be passed your so very soon and your digs are fine and also the GP..

> drop her head and go as slow as a snail and look like she was slightly lame on her near fore leg.

Have her elbows been checked? Buster has ED, dropping his head is a sign of his elbow playing up ('nodding' while walking can also be a sign of front-leg pain). The ED has not been opperated on and from time-to-time if he over does things he will be a lot slower in the mornings untill his elbow has 'freed' up. Yesterday he was very energetic on his walk, choosing to run & jog most of the way (for Buster that is amazing as he's generrally a plodder), so this morning he has been very slow and tired looking, but as I know what it is, I just encourage him to walk around which seems to get rid of the stiffness.
Before the diagnosis, I had to get some home-video footage of Buster to show to the vet as he alwasy acted normally in the vets!
When Buster was at his worst with the ED, he didn't have a very bad limp, it was more a reluctance to exercise or to get out of bed :(

Possibly hypoglaecemia? - low blood sugar. I had a terrier with this years ago. She would be absolutely fine, then just run out of steam, lie down for a few minutes and was then better. I was advised to take a Mars Bar with me and give her a bit - that did the trick.

This wouldn't necessarily show on the bloods if she was OK when they were taken.