The reason for cerfing your litter is to determine if there are any issues you need to know about for the pups you have produced that are going to their new homes; and for your future breeding program.
I had a litter cerfed by a board certified (ACVO) canine ophthalmologist (which I do with every litter) where one pup was diagnosed with Incipient Posterior Cortical Cataracts.
This is a condition seen often in King Charles Spaniels and I was advised by my canine Ophthalmologist that it usually goes away in 4 weeks and the dog will never have any eye issues for life.
However this vet/Optho advised me not to breed a pup from this litter or to ever repeat the breeding, which I have not and will not.
The pup was checked 4 weeks later and passed the cerf. Otherwise I would have paid for the surgery if needed.
That is the right thing to do as a reputable breeder.
There are dogs out there with issues that some breeders feel are a “non issue” and, therefore, keep breeding those lines.
I choose not to do that.
My reputation as a breeder is only as good as the pups I produce. And, therefore, I choose to spend the extra money to cerf my litters before they go to their forever homes.
Pups should not be cerfed prior to 8 weeks of age. If you check with your local Optho vets they often offer certain days of the week that are a “clinic” price.
Take the time and money to do this please. It is for the sake of your pups first and foremost, not to mention your reputation as a reputable breeder.