Breeding Blog
“Ut est rerum omnium magister usus”
~ Julius Caesar
“Experience is the teacher of all things.”
[Kody, Seren, Llangwm Ffansi]
Section 2: Jan 2026 – Present
16-April-2026
Frozen Semen Doses
The famous American social commentator, Upton Sinclair, said:
“It is difficult to get a man to understand something, when his salary depends on his not understanding it.”
And so it is with the purveyors of frozen dog semen.
The use of frozen semen for working collies is little understood by the UK purveyors / suppliers.
A stud fee is paid for natural matings, often (most often?) involving two ties. The amount of semen deposited is 300 million to 2 billion. The normal sperm count in an ejaculate for a healthy, 2-7 year old, adult dog is 500 million – 800 million. In two ties, we could expect over 1 billion healthy sperm to be delivered to the uterus. The typical life expectancy of a sperm from a natural mating once in the uterus is 5 days.
Frozen semen is collected by hand, an ‘extender’ added to assist with freezing and thawing, and frozen in ‘doses’. A test is done to simulate what proportion of sperm will survive a thaw. The result is the number of post-thaw motile sperm. A ‘dose’ is whatever the collecting veterinarians says it is. The absolute minimum for frozen transcervical insemination (TCI) is 100 million post-thaw motile semen. The recommended number of post-thaw motile sperm is above 200 million, closer to 250 million. The higher the number, the greater the likelihood of successful of a normal-ish size litter.
A typical collection of 500 – 800 million healthy sperm with a 75% post-thaw ratio should result in 400 – 600 million viable sperm. The question then becomes: how many doses is that for the supplier to sell?
Using the bare minimum per dose, that is 4 – 6 doses, each priced at the standard stud fee …often times more, to account for the collection costs ($300-$500). Using a dose more apt to produce a good litter, that is 2-3 doses.
It is easy to see the divergent interests of the supplier and the buyer of frozen semen. The stud owner has an incentive to maximize doses, cut the ejaculate small. The buyer benefits from a larger dose.
…and now, just look at the math. By going to get a dog wanked, the same dose (or likely much lower) as a natural tie, just once, a stud owner has the potential to collect multiples of his normal stud fee, more if it cuts the dose smaller. Natural matings produce more sperm that survives longer, and are often done twice. A frozen mating, where the sperm survive only 12-18 hours, receives only a fraction –sometimes a very small fraction– of the normal ejaculate.
Artful stud owners choose the collecting vets who spread a collection into the maximum number of doses and charge a full stud fee for each. That, unfortunately, is now the standard practice in the UK.
The cunning sellers of semen, who know nothing about artificial insemination, don’t want to hear how unfair this system is …because the system as it has evolved maximizes their returns. And those who take the semen from overseas have to take it or leave it …or as some of the purveyors have suggested, purchase multiple doses for one frozen mating.
A fairer approach is for the buyer to pay the collection fee purchase the entire collection, with post-thaw doses of 250 million sperm. If there is more than one 250 million sperm dose, the buyer and seller agree as to whether the buyer pays for the extra dose of the seller retains it. It would be very unusual for there to be more than 3 doses from such a collection. The buyer might even want to use a second doses for the same mating, for better results.
The tricky bit is making sure the buyer does not game the system and himself sell on fractional doses. That can be handled by the record of collection which is supplied to the veterinarian doing the TCI and the registration organization (ISDS or ABCA). The veterinarian and registration organization verify the ‘dose’ received / used for TCI is as noted in the record of collection.
The stud owner is likely still better off than a natural mating, since it is likely he will have 2 doses from one collection. The buyer is better off because he has paid for a more appropriate dose, more likely to produce a successful and normal size litter.
I am not supposing much will change with the dominant sellers of semen. There is money at stake. However, for my own part, I choose to work with stud owners and repro vets who consider both the buyer and seller’s interest and work toward a fair contract.
I sell semen from my own stud dog, Peter, and the doses sold are 250 million post-thaw semen, just what I would use myself. And stud fee is the same, whether it is a frozen TCI or natural breeding. And to all those wanting to breed with Peter, I tell them that frozen is a last option. A natural mating with 1 or 2 ties is always the better option. Mostly, the frozen semen I collect from Peter for my own use, for when there is no more Peter.