Mycoplasma/Stud Refund - Page 4

"because the # of puppies is dependant on the female, not the male - if he sired one puppy, he had plenty of semen to sire 12.  "

I'm not sure I agree with the above. Sperm motility, number of leukocytes and morphology play a large roll in the number of eggs fertilized.  I worked in a lab for years looking at sperm, and  the male was the first to blame for small litters.

Some stud dog owners think they can take the money and run, several years ago I took my maiden bitch to a well known champion stud dog in the midlands, did all the blood tests first, she was ovulating, did first and second matings, no pups. Repeated the same on her next season, no pups. As the bitch's next season approached I discovered the stud that had produced male and female champions previously hadn't sired a single pup since before I first used him over a year earlier, when I questioned the stud dogs owner about this she decided to reveal the dog had been diagnosed with an infection but it was ok now, at her insistance the mating was repeated for a third time, again no pups. This was the time the stud dog owner chose to start rubbishing my bitch even involving her friends in the process, for what it's worth my bitch got in whelp the first time she was mated to another dog. According to the KC the stud in question never produced another pup.

Normally even if the male is low fertility, he still has plenty of semen to fertilize 6-12 eggs.  even a low-fertility male, as long as he's not completely sterile, and with the right timing for the female's cycle, can and will sire a  normal-sized litter.  If he's sterile, not so much.  a fertile male will have  billions of sperm for every breeding.  an infertile (but not sterile) millions, or maybe thousands.  plenty to fertilize a normal-sized litter.

all repro specialists I've worked with (many) have given the female credit for the number of puppies in a litter, as she will produce a finite number of eggs, and the male will produce far, far more than enough sperm to fertilize all of them - along with the fact that sperm can live inside the female for 3-7 days (plenty of time for all eggs to be fertilized even if some are not mature at the time of breeding). 

That said, I've had stud dogs who routinely sired small litters, even with females proven to produce large litters.  Semen as tested was "good" - not excellent, not fantastic, but "good".  plenty there swimming straight to sire big litters.  But  he didn't - so ????? repro specialists guessed that perhaps there was some incompatibility between the males' semen and eggs - perhaps they would fertilize the eggs but then the eggs would die, or some of the fetuses would be aborted mid-pregnancy - some sort of fatal gene?  He always sired litters, rarely missed a female, but his normal litter size was 2-6 puppies with more often 3 or so.