Right i have been on amazon tonight looking for a new book or two.anyway came accross the in the womb dogs- and thought i wondrer if this can be watched online.sure enough i watched it online.
heres the contadiction.

She says the males sperm can live inside the female for up to a week waiting for the egg to mature,it looked like it had attached itself to the wall.
so then she went onto say after the egg is mature the sperm knows this and conception takes place.so if conception takes place a week after the 1st mating how does the first day of mating count as day one?it cant be can it surely.this i assume is why some dogs are later than the average.

unless.......someone can explain this a bit better for me(huge grin)...lol.

Day one goes from ovulation not mating hence the difference very often in delivery days.

The first day of mating is used a rough estimate as to when the bitch will give birth as generally they won't stand until they are ready to mate (there are the odd exceptions on this though!) so this isn't exactly when the bitch conceived... So you are right in saying that some bitches go over the 63 days when infact they probably aren't over, they are just right from conception not the mating. where as bitches that go earlier probably had ovulated acouple of days before the matings took place. Not sure if others agree, but that is how I look at it anyway. :-)

The peak time for mating is generally when the bitch is ready to stand, when the egg is mature and ready for fertilization the bitches body and hormones send that signal which is why she will go from flirting to actually allowing a mating, it is also the time when the male will go from pestering to becoming more frenzied. Nature as always gives the correct signals for the right time to mate, it's what we should always trust in it is how species survive.

This is why IMO the more natural matings where the male and female are allowed days or the week together for flirting and awaiting the correct body signals are much more likely to be spot on for the date of whelping. My bitch has always been to the date without fail, as opposed to the scientific approach or us deciding it must be about right. It's interesting that you have read one week for sperm to stay live, I guess it must be right, but personally I believe it to be more like 3-4 days, I wouldn't really expect sperm to be alive much after the 4th day, but guess I was wrong about that. :-)

It's abit like us 40 week term but infact it is only 38 weeks !!!!! At the end of the day it is only a guide.

That is quite right, buitches are actually very reliable at whelping + or - 1 day the same number of days after ovulation (can't remember how many days), the rest of the difference is down to mating being various days before or after ovulation.

Found this very interesting question and answer session with a  repro specialist: http://www.dobermann-review.com/info/breeding/canine_reproduction.htm

quote: "The bitch's due date, 63 days from her ovulation date, the date she went above 5 nanograms progesterone. Breeding date has nothing to do with whelping date It's the OVULATION date. So if you know the day your bitch goes above 5 nanograms, you can set her due date at 63 days from that as her whelping date: set up your whelping box, take the day off work."

Thsi would account for why my bitches and most in our breed whelp in under 63 days as they tend not to stand (or males wait to mate) until after ovulation, in the two to 4 days after, when their eggs are ripe.

so interesting isnt it.trust me to ask all these questions lol.

thanx its not black and white is it.lol