I have a draminski ovulate and think you can only use it as a guide. The rest is being observant and a bit of luck and common sense I guess.
I had a long trip to the dog and using the draminski and watching how she was with my others including my neutered dog ( who is a very good indicater) I went for the first mating at 15 days. We had a 2nd mating at 17 days.
I used the draminski again and the reading had gone down so I was as happy as I could be I had gone at the right time. She was still bleeding but I wasn't concerned as have had that for at least a week afterwards in past matings.
However to-day there have been some odd signs ( 21 days). I saw some fresh blood on the floor and to be honest she has been so clean I have barely seen any apart from on her. She has been flying around with my neutered dog, backing up to him, turning her tail and showing all the signs that suddenly she is ready now? I know that some matings are successful at 20 days.
The 17 day mating was Monday.

Hum.   Did the stud dog 'oblige' at the time?   I tend to go with an experienced stud dog who won't usually do the job unless HE knows the bitch is right-on.... to say nothing of her accepting him!!

I have had a bitch come back into producing a blood-coloured discharge through the final week after two good matings, on days 11 and 13.   As mine usually had little to no appreciable discharge through the final week, and certainly not blood-coloured, I started to believe she'd not taken.   But after an uneventful pregnancy, she produced (albeit via C.Section after secondary inertia) 9 really super puppies.   Possibly the best we'd ever had (coming back to the UK with the 3 we kept, one became a UK Champ. and the other, her sister, perm.qual. for Crufts - their brother is back of a number of lines in the UK now too.

Fingers x-d she's now in whelp 

Oh I really hope so as desperate to keep a bitch to show as although she is very nice and did well as a puppy she has now decided that the ring is not for her. My alert bouncy girl at home turns into a sack of potatoes at a show grrrr
The two matings went very well and were not problematical. She was keen enough and both resulted in a reasonable length tie. I realise of course that a tie is not everything.
Just wondered whether others had experienced a bitch that still seemed to flag 4 or 5 days after the last mating..

Mine certainly will continue to hump with the bitches at home to well past 21 days and will bleed right through to the end of the season and even to a full month and still taken.

At a seminar with a canine reproductive specialist someone asked about6 the Draminski, and the specialist said it was not reliable for bitches as it is designed for cattle, and any success is coincidental as bitches have such a wide window of opportunity for mating and subsequent pregnancy compared to most species.

Just wondered whether others had experienced a bitch that still seemed to flag 4 or 5 days after the last mating..

Gosh yes, every time.

I've only ever relied on the stud dog to tell me when the bitch is ready, never done any sort of testing, and have so far never had a missed mating, every single one has resulted in pregnancy.

Thanks for all your replies. I too have only ever missed with one bitch who was mated over 3 seasons and in the end 2 different dogs just in case but never took. Obviously the problem was hers. This would be the 2nd litter for this girl.
I understand what is being said about the Draminski and would not take it on its own as red so to speak. I find the readings a bit haphazard and always seem to land up contacting the people I bought it from for reassurance. The only thing about it is you can see a rough trace pattern and last time I used it after mating and the readings had returned to pre season levels indicating that ovulation had passed.
I'm keeping my fingers x'd over this one and will keep you posted when I have some news one way or the other.

I had my bitch scanned to-day by my vet. He never talks numbers just points out what he sees.
He was ages and first of all said there was nothing there and I was already discussing a miss. AFter a bit he says oh that might be something, then came up with 3.
She is 28 days to-day 2nd mating 30 1st mating.
3 would be a small number for my breed but of course better than the original verdict. I am thinking of making an appointment in a few days, not with my vet but with a private scanner
who scans from her home. I did use her a couple of litters back.
Has anyone experienced more pups at a later scan than an earlier one, and being told she had nothing then finding 3?

Congratulations that there are pups. Your vet doesn't sound all that good at scanning. Of course, it IS rather early still if she took from second mating, and some vets not all that used to scanning prefer to do it past 30 days. I have had one vet in the past tell me there was ONE pup, only for TEN to be born. Thankfully my new vet tends to be spot on, every time the bitch has had the exact number seen on the scan, or one more.

Thanks for that. So it sounds like it could be worth going again. ( I was once told 6 and had 11 with her grandmother)
She had 10 last time - of course I know that is nothing to go by. It would be nice to know whether he is accurate as I can let
puppy buyers down gently. If only a small number they ought to look elsewhere.

OK I did go for another scan to-day but with a private scanner much more everyday experience with scanning.
I have been told before when I went with her Mum that she was very gassey and it is possible this can mask puppies.
I've tried to look this up and one site said gassieness in the uterus can be caused by dead puppies.
I have sent the lad a message as feel a bit daft now. Not sure if she meant in the uterus or in the stomach?
Anyone else been told this on having a scan and if so what was the end result of the litter?

The gas is usually in the gut (which shares the abdominal space) and is often seen on x ray so bound to be noticed on US.
Don't worry.