does the sire or dam determine size pf puppies

Question
Hi,
Can you please tell me if the sire or the dam of a litter is the one which determines the size of the puppies at birth?  I have heard both ways.  Also, does the number of ties determine number of puppies? (More ties, more puppies?) My vet kind of fussed at me for allowing 4 ties when I bred my girl, stating that it resulted in her having too many puppies.(6) Thanks, Lani

Answer
Both the sire and the dam contribute to the size of the puppies, along with grandparents on both sides and all the way back to the fifth generation. Which is why breeding a very tiny female is always dangerous no matter the size of the dog being bred to her. You have to take into account the size of ALL the dogs in their genetic make up for at least five generations,
As for how many ties.If your bitch has ovulated, then she only releases a certain number of eggs to be fertilized. It takes sperm at least forty eight hours to regenerate (live sperm) so a breeding any sooner is just an irritation. More breedings can increase the size of the litter if the dog continues to produce live sperm that continue to fertilize the eggs produced by the bitch. Which can lead to pups in the litter not being conceived on the same date and some being early born and some late. The best way to breed is to have your vet do progesterone screens and  cystology to determine the optimum breeding date for your bitch. Breed her that day and preferably no more, if you INSIST on two breedings,. don't repeat for 72 hours. I've seen dogs with one breeding have sixteen puppies and dogs with four have two.
Hope that answers your questions
Cindi :)