Im just curious how often do dogs have a singleton puppy and what causes a singleton?
thanks xx

i dont know, i havent bred a litter but could it be down to the bitch?  my youngest dog was a singleton (the mothers second singleton), my breeder has had one last try and said she had her mated very early this time and has just had 3 pups, which is average for our breed. dont know whether thats the answer though, sorry.

I had a bitch have a singleton then go on to have 7 puppies.  Think there are a variety of factors from age of the bitch, the fertility of the male, temperature at mating & all sorts. 

I've had a singleton from my girl, she was mated to the same stud dog 18 months later and had 7

Not sure what causes a singleton, except that it's the bitch that decides.  I do think that maddog is right about a multitude of factors affecting numbers though.

Not sure what causes a singleton, except that it's the bitch that decides.

Not always true I am afraid. I mated my girl to a dog and had a singleton, later turned out that it could have been him who had a problem, although not easy to prove one way or another and there is a possiblility she was mated at the wrong time of course, but I would say it could be either. She carried two litters of 9 to other males, one prior to the singleton, one after.
Aileen