How old is too old?

I have an entire male dog and recently a friend enquired if they could use him at stud. He's 14 years old and has never been used before, so there's a chance he won't have a clue what to do in any case, but is there any negative health wise for a much older male siring a litter?
He's got a lovely nature and has always been very healthy.
Should I let him try?
The owner of the bitch has lots of people on her waiting list and to be honest I would love one of the pups, too.
Simon Edrich, Chester

You are indeed lucky to have a fit and healthy fourteen year old dog, whatever his breed, and I can understand why you would love to have one of his puppies. Generally, any dog used as a stud has a good clean pedigree and a proven track record in the ring, be it show, obedience or trial, for example. He will be passing on traits to his offspring, as will the dam, which should all be desirable for that breed.
If this was a fourteen-year-old bitch then I think that no-one would be in any doubt as to the answer. I do remember the case of a twelve or thirteen year old bitch who had been unknowingly mated. In fact, the owner was totally unaware of her bitch being pregnant until she ran into problems and, to cut a long story short, needed a Caesarian. Needless to say, it did knock her for six, but she successfully reared her two puppies.
For an older dog, the only physical demand is the actual mating. He will play no other part since he does not live in the same household. The bitch obviously goes through pregnancy on her own, and the dog is generally not at all involved in rearing the puppies. There is therefore no comparison either with the situation with an older human father.
There are six points, however, which do spring to my mind as being important to consider:
1. Inherited diseases are not just a consideration for the young bitch mated to a young sire. You do not mention what breed your dog is – and I am assuming he is a pedigree purebreed - but he should still be screened for those inherited conditions appropriate to his breed. For example, if he is a Labrador retriever then his eyes, hips and elbows should be screened. Temperament is certainly very important indeed, but as the owner of the sire you would not want him to be passing on a serious inherited defect. It follows that the same applies to your friend’s bitch, as well as all the care needed during pregnancy and the risks involved, let alone the costs;
2. How many times have people said that they would love to have a puppy from a litter, only to back out when the litter has actually been born? There are so many puppies around from reputable breeders, and so many puppies and adults in rescue centres;
3. Fertility – being an older dog, it is likely that he will be less fertile, ie have fewer viable sperms. I would have thought that there would also be a higher risk of abnormal sperms which may affect the number and health of puppies developing through to birth. You have not indicated how old your friend’s bitch is but do remember that age will also affect the fertility of the bitch, and the Kennel Club will not register puppies born to a dam less than a year old at mating or more than eight years old when the puppies are born;
4. The mechanics of mating do require the dog to rear up on his hindlimbs. Although it is usual for the dog to turn to achieve a tie ,which may last as long as twenty minutes, bitches will conceive without this stage occurring. If your dog has arthritis, this may be painful for him so should be considered carefully. If it does not put him off from mounting the bitch, in how much discomfort will he be?
5. Mating does involve exertion. An increase in heart rate will put additional stress on the heart. The heart of a fourteen-year-old dog will have been beating for fourteen years and coping with the slow demands of old age. What effect might the exuberance of mating have on it?
Maiden bitch and first-time sire is not always a good recipe for success. It simply may not happen, in which case your friend would be best advised to find an experienced stud dog with a proven track record.
So, not a straight forward decision which is, after all, why you have posted on the Think Tank! The chances of failure are undoubtedly higher than with a younger, proven stud dog. It may be that if you were to decide to go ahead, both dogs having passed screening tests, the bitch might not have a live litter anyway, with a failure anywhere along the way from mating through conception and ultimately to delivery.
Alison Logan, vet