I know that its down to how many eggs the dam produces but a sire belonging to a breeder i know has produced a string of tiny litters from girls that usually produce large litters( from different sires).His owner is going to have him tested for low sperm count etc.would this make him produce small litters ie litters of 2 or 3?

well presumably if there's very little viable sperm then yes....

Reckon a stud would have to be all but sterile to have any effect on the numbers, after all 24 eggs and 24 sperm just would not do and even with a low count one would expect it would be the number of eggs produced and the number implanted not the number of viable sperm. As far as I know a dog will either produce viable sperm or it will not although illness or overheating can have a temporary effect of the studs ability to produce viable sperm.

I'm no expert but quite a few years ago but in my breed they tested 30 males on the club stud register and quite a few came back as low count or with abnormal sperm(and few with no viable sperm)
If lot of the sperm of the dog is abnormal maybe it is unable to swim effectively meaning not able to reach eggs in time?
This could have an effect on litter size?

Or another factor if the sperm is fine could be that for some reason this male tends to mate the bitches right at the end of the period the eggs are viable (and not before) meaning some eggs have died before sperm gets to them. Of course the mating time is also determined by when the bitch stands but some males can also be very particular on when they will mate.

> Or another factor if the sperm is fine could be that for some reason this male tends to mate the bitches right at the end of the period the eggs are viable

Or of course a male who mates a bitch as soon as presented, so too early.

With fewer stud owners offering to board a bitch, bitch owners not wanting to leave their bitches or feeling unable to travel for more than one mating, this could be an issue.

If males are never given the opportunity to court and learn when a bitch is ready, but only gt presented with one and then she is taken away, they can get into the habit of mating anything presented (and maybe forced/restrained).

Or of course a male who mates a bitch as soon as presented, so too early.

Can it really work that way? With a bitch that is willing? Say you let a dog mate a bitch on the very first day she is willing, could that mean the litter would end up smaller? Because if that is the case, I will do ALL my future matings that way!! The less pups the better. For my next planned litter I will be using a dog of my own so no travelling involved, so would be easy to mate the moment the bitch accepted him. (Assuming the dog is willing, that is.)

Think that would depend on how the bitch ovulates - some may produce a few ripe eggs over a few days and others within a few hours. Not sure there has been any work on this.

> Can it really work that way?

many bitches will stand at the point of the LH surge about two days before ovulation, where the eggs won't be fertilizeable for 4 days. 

Assuming you have a male with reduced fertility (due to age or whatever), there may be Little viable sperm left to fertilise the eggs.

It has been shown that bitches whelp 63+/- a day from ovulation.

My Inka was mated days 14, 16 and 18 when I went to USA, and whelped 66 days from first mating, which would suggest she had yet to ovulate.  She had 5 live and 1 stillborn pup.

This time she was mated days 16, 18 and 19, whelped 62 days from first mating which points to having mated at or a day after ovulation. 

This time we had 7 live pups (though we lost one in the first few days) and two stillborns.  The bitch had been unwell after her usual food had a major recipe change, so the last two weeks of pregnancy and after whelping was a nightmare with her not eating.

A lady I know who had a champion in a large hound breed (her main breed being a toy breed) chose to use an old stud and only mated once the moment she showed wiling, and had just 4 pups.

.

Do respect your knowledge and experience Brainless but to come to a conclusion on a small sample is not likely to be reliable - worth a try I suppose as long as the result does not matter too much.

According to Goldmalis own website her first litter was an accidental mating.  From the description it would seem it took place as soon as the bitch would accept the male and resulted in 10 puppies.

My first litter was day 13 which was the first day my bitch would mate and resulted in 7 puppies. Interestingly my mentor had a Draminski ovulation detectore and declared that my bitch had gone over and we would not get any puppies.

Next litter was 10 puppies, Bitch mated on day 15. She was ready earlier but we couldn't get to the stud before that for various reasons. Only one mating.

My most recent litter Mating was done 2 days after ovulation as per Idexx testing Only one mating and resulted in 10 pups again. Different bitches and sires in all cases.

I was told by the owner of the sire of my girls first litter that he only threw small litters. I was surprised at this as I thought it was the bitch alone that determined numbers. Sure enough she had 3 puppies. The following year with another sire she had 7.