Age to Breeding Male Dogs by: Donna - dog-beds-n-beyond
Hi Sherry,
Thank you for your question.
Puberty is reached about 6-12 months on the average and sexual characters are developed that allow the male to mate, but prior to one year, the sperms may not be fully developed and fertilization that leads to pregnancy may be poor.
Since your have medium sized breeds, they may take a little longer to reach full sexual maturity than a smaller breed.
Beyond that however, it is recommended by most veterinarians that you wait to breed until a conclusive health test can be preformed at 18-24 months. Each breed has health issues associated with them that could be passed down to the puppies.
If your male dogs (unlike bitches) are healthy they can remain sexually active and fertile into old age.
Your Border Collie is past this age but it should be noted that the AKC will not recognize a litter from a male under 7 months or over 12 years of age.
Health issues for Border Collies - Hip Dysplasia, Collie Eye Anomaly which effects the retina, choroid and sclera of the eye, Elilepsy and Osteochondritis Disease which like Hip Dysplasia is a joint disease.
Health issues for Australian Shepherds - Hip Dysplasia, eye problems, allergies, Thyroid Dysfunction and Heart disease. Here is a link you may find helpful...
