|About Our Dual-Sired Breedings
~ Fall 2003 ~
|1. How were the breedings accomplished?|
For each of the two litters, semen was collected from one sire and, because of the geographic distance, the collection was cooled (not frozen), specially packed, and FedEx'd overnight to our local representatives of the International Canine Semen Bank (ICSB). Once the shipment was received and unpacked, the collection was carefully warmed to body temperature, mixed with fresh semen from our own champion male, and then surgically implanted directly into the uterus of the dam. The procedure was performed by a veterinarian while the dam was under general anesthesia The entire implantantion process from start to finish took less than an hour.
2. Can a puppy have two fathers?
No -- but the litter can be sired by two dogs. It is possible for some puppies to be sired by one of the males and the rest of them to be sired by the other male. Of course, all puppies in the litter would have the same mother.
3. Can the litter be registered?
Yes, it can under the rules of the American Kennel Club's DNA Certification Program. All parents and offspring of a dual- or multiple-sired litter must be DNA-tested so that the correct parentage can be determined. Once the DNA testing is completed and the report is evaluated, then the litter can be registered.
4. How is the DNA testing done?
Cheek cells are collected from the inside of the mouth of each puppy and sent in to the AKC for DNA testing. Puppies as young as just a few days old can be tested. The results are returned to the breeder in about six to eight weeks.
5. Why breed to two sires?
Primarily to obtain a nice selection of puppies to choose from - with less time spent. It is always possible that one combination of parents will produce puppies superior to the other combination. A dual-sired litter may enable more effective forward progress in a breeding program without having to breed two separate litters a year apart. We expect that all four combinations of parents in these two breedings should be quite nice. This method simply allows us to evaluate the different combinations at the same time, assuming there are puppies by all sires.
A second reason is to help ensure that there WILL be puppies! Statistically, semen that has been collected, chilled, and shipped appears to be less effective in achieving conception. Mixing fresh semen with chilled, shipped semen serves to "cover the bases." A "miss" from a single-sire chilled semen breeding always leaves the unanswered question of whether the "problem" lies with the sire or with the dam. Besides being very disappointing, a "miss" also means having to wait nearly a year before attempting to breed the dam again.
So, welcome to our "brave new world"! We are hoping for two healthy litters with puppies from each sire. Please check back to follow the results of these two breedings. They should be very interesting!
December 8 update:
The first litter (Kristi's) was whelped on November 28. There were six puppies in total. Unfortunately, two were stillborn and a third was lost about 48 hours later. Remaining and thriving are one sable female, one tricolor female and one sable male. We suspect that the male might be sired by Craig and the two females by our Simon. However, we have ordered DNA test kits for all six puppies in order to learn exactly how many puppies were by each sire.
The second litter (Steffi's) was whelped via c-section on December 8. There are two puppies: a sable female and a tricolor male. At this time, we have no opinion either way which potential sire might be the father of each of these puppies. The two puppies look very similar to each other, so there may be only one sire of this litter.
We are waiting to receive the DNA kits from the AKC so that we can collect and submit the samples from the puppies in both litters.
December 29 update:
Our DNA test kits arrived. Cheek cell samples were sent in via overnight mail on December 12 from Kristi's litter and December 19 from Steffi's litter. We received an e-mail acknowledgment from AKC on December 24 that the samples were being processed.
At this point, there is nothing more to do than enjoy the puppies and continue to play the "guessing game." At birth, the sable male in Kristi's litter looked distinctly "different" from his two siblings. However, at three weeks, he and his tri-color sister looked quite similar to each other while the sable sister was definitely the "odd person out." But by four weeks, the girls were back to looking more like each other. By five weeks, it will probably change again!
Steffi's two puppies continue to resemble each other as they grow. Time (and DNA) will tell the outcome for all...
January 28 update:
DNA results on both litters became available today. Because of the delay caused by the holidays, the AKC DNA Operations staff was kind enough to fax us the results. The outcome was as follows:
Kristi's Puppies (Ch. Burlywood Brand New Day, HIC):
Leo (sable male) - by Ch. Burlywood Bestseller, HIC ("Simon")
C.J. (sable female) - by Simon
Abby (tricolor female) - by Ch. Barksdale Beneficiary ("Craig")
Also, there were three deceased puppies from this litter. The DNA results on these puppies revealed two were sired by Simon and one was sired by Craig. So, out of six puppies, two came from the chilled-semen breeding and four were from the fresh semen breeding.
Steffi's Puppies (Ch. Burlywood Breakaway, HIC):
Zoey (sable female) - first-round DNA profiles are insufficient to determine which is the sire
Bartlet (tricolor male) - preliminary DNA profiles suggest that he is by Simon
Additonal DNA markers are being requested of AKC on both puppies, their dam, and both of the potential sires.
February 28 update:
Additional DNA markers were received from AKC on the two puppies, Bartlet and Zoey, their dam, Steffi, and both potential sires, Bone and Simon.
To understand how the DNA results are interpreted, remember that each parent contributes one allele to each gene. If an allele does not match either possibility which a parent can contribute, it is called an exclusion. As a general rule, a single exclusion does not rule out a dog as a potential parent because the exclusion could be the result of: a) a mutation, b) a statistical blip, or c) a laboratory error. For AKC's purposes, two or more exclusions rule out a dog as a potential parent of a given puppy.
On the table below are the extended DNA profiles of all the dogs involved in Steffi's litter. Within the first 14 markers, there is only one exclusion on Bartlet's profile (PEZ 12) against Bone as a sire and NO exclusions in Zoey's profile against either sire. Note: the marker GEN confirms the gender of the animal and is used for quality assurance in the testing process.
|DNA Analysis - Steffi's Litter|
|However, when the profiles were extended to
17 markers, an additional exclusion was found on Bartlet's profile (PEZ 10), giving him two exclusions and ruling out Bone
as a possible sire. Simon is Bartlet's father.|
On Zoey's profile, there was only ONE exclusion against Bone and none against Simon. However, since this single exclusion was located on PEZ 10 as littermate Bartlet's was, AKC DNA Operations analysts concluded that Zoey was also sired by Simon. They felt it was extremely unlikely that a mutation or error was the cause of the exclusion. Indeed, a littermate with the same exclusion serves as validation.
So, we were half right and half wrong. We were right about C.J., right about Bartlet, unsure about Zoey, and dead wrong about Leo and Abby. We had those two switched. And, no, they didn't mix up the samples because remember, the markers for gender (X and Y) are included as part of the profile!
It certainly has been a very interesting journey. The advantage of doing a dual-sired breeding has proven to be an increased opportunity to allow for genetic diversity within a single breeding. The disadvantages, of course, are the higher costs, the uncertainty felt during the wait for DNA results, and the fact that results might be a bit difficult to get one's head around. It's easy to make assumptions about who might be who. You have to be prepared for the "what if's" - if your assumptions are incorrect.
Would we do it again? ABSOLUTELY - in a heartbeat! It's been a truly amazing learning experience!
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