Goal: Determine if NWZ-B carries the "En" (broken) gene.
Result: No Brokens in the four offspring.
Conclusion: Not enough evidence to prove NZW-B does not carry the "En" (broken) gene. Another test breeding with a self (solid colored) doe would be provide more evidence.
Result: No Brokens in the four offspring.
Conclusion: Not enough evidence to prove NZW-B does not carry the "En" (broken) gene. Another test breeding with a self (solid colored) doe would be provide more evidence.
I knew it was unlikely, but I still tried a breeding with one of our new junior NZW bucks, NZW-B, and our youngest brood doe, Golden Girl, on September 9th. It did not take. The buck may have been too young as he was just three months old at the time, but Golden Girl had an entire year off from breeding, so the fault could have been one or the other or both. Usually, I would not try breeding a buck quite that young, but we have had accidental pregnancies from NZW bucks about that age and I had no bucks older. So, I rebred the same pair on October 9th and got results on November 9th! Golden Girl had not kindled as little as four kits previously, but I was pleased with their sizes and health.
 |
 |
| __ __ cc __ __ | _a B_ Cc Dd EsE Sisi enen |
| Ear Tag | Gender | Color | Genotype |
|---|---|---|---|
| BGG1 | Buck | White | __ __ cc __ __ |
| BGG2 | Doe | White | __ __ cc __ __ |
| BGG3 | Doe | Gold-Tipped Black Steel | A_ B_ Cc D_ EsE |
| BGG4 | Doe | Black | __ B_ Cc D_ __ |
At the time I was thinking that we would be crossing NZW with Silver Foxes as we had been doing, so my goal was to test breed the NZW bucks and hopefully find at least one of the three that did not throw Brokens (spotted). I was very pleased to see no Broken patterns in this kindle.
BGG Kindle Genetics
Having only four and two of them being Red-Eyed Whites, which would hide the dominate "En" (broken) gene, I did not feel that was evidence enough to eliminate the possibility that NZW-B is a Broken carrier. However, two of the colored kits did not show Broken, so it is also still a possibility that NZW-B is not carrying Broken.
In addition, there is the question if NZW-B is carrying Steel. Since the Steel gene "Es" is also a dominate gene that can be hidden by other genetic factors, I would not be able to eliminate that trait with this breeding. In fact, the BGG4-Black doe is a bit of a real mystery, genetically speaking, because of the Steel gene being in play.
All these bunnies have the potential to carry Steel from their mother. However, what if the father also carries steel? BBG4 has the potential of being several genotypes and the reason I find her particularly interesting is that she has Silver Fox no-fly-back fur. It is highly unlikely that she will silver although not impossible if the father has a recessive Silver gene, but I am seeing no signs of it at this time. She does have the undercoat slate color seen on Black Silver Foxes, so it is likely that she has the typical Self genetics as with a Black Sliver Fox.
She could simply be:
However, she might also have a Steel gene that is dominate yet hidden due to the combinations on the "A" and "E" loci. I was told that a Steel rabbit must be an "A" Agouti (or even "at" Otter) to show Steel, so the "aa" Self genetics would hide it, but it seems to be a bit more complicated than that. I have also read that there is an exception in that aaEsE-Self with the Steel and the Extension gene will show Steel and that is why I cannot be certain of whether the mother, Golden Girl, is is aa-Self or Aa-Agouti. If BGG4 is aa-Self then she could be these combinations and not show Steel:
BGG Kindle Genetics
Having only four and two of them being Red-Eyed Whites, which would hide the dominate "En" (broken) gene, I did not feel that was evidence enough to eliminate the possibility that NZW-B is a Broken carrier. However, two of the colored kits did not show Broken, so it is also still a possibility that NZW-B is not carrying Broken.
In addition, there is the question if NZW-B is carrying Steel. Since the Steel gene "Es" is also a dominate gene that can be hidden by other genetic factors, I would not be able to eliminate that trait with this breeding. In fact, the BGG4-Black doe is a bit of a real mystery, genetically speaking, because of the Steel gene being in play.
All these bunnies have the potential to carry Steel from their mother. However, what if the father also carries steel? BBG4 has the potential of being several genotypes and the reason I find her particularly interesting is that she has Silver Fox no-fly-back fur. It is highly unlikely that she will silver although not impossible if the father has a recessive Silver gene, but I am seeing no signs of it at this time. She does have the undercoat slate color seen on Black Silver Foxes, so it is likely that she has the typical Self genetics as with a Black Sliver Fox.
She could simply be:
- aa B_ Cc D_ E_ - "aa" Self Black
However, she might also have a Steel gene that is dominate yet hidden due to the combinations on the "A" and "E" loci. I was told that a Steel rabbit must be an "A" Agouti (or even "at" Otter) to show Steel, so the "aa" Self genetics would hide it, but it seems to be a bit more complicated than that. I have also read that there is an exception in that aaEsE-Self with the Steel and the Extension gene will show Steel and that is why I cannot be certain of whether the mother, Golden Girl, is is aa-Self or Aa-Agouti. If BGG4 is aa-Self then she could be these combinations and not show Steel:
- aa B_ Cc D_ Ese - Self Black with Steel and the non-extension gene
- aa B_ Cc D_ EsEs - Self Black with double Steel
Even as an A_-Agouti, BGG4 may not show any Steel with these combinations, although I have read a double Steel can have a deeper color throughout the hair shaft and would not likely have a slate color undercoat:
- A_ B_ Cc D_ Ese - Agouti with Steel and the non-extension gene
- A_ B_ Cc D_ EsEs - Agouti double Steel
I am a bit torn about BGG4 because she is a NZW/SF 75/25 cross with a good growth rate, SF no-fly-back fur, and a sweet temperament. When I first saw her, I just had this feeling she had something special to work with in developing our Silver Fox lines and I have been considering keeping her to grow out for at least one breeding or two with a SF buck to see if the offspring will silver or show steel. If she is carrying Steel, I would not want that added to the genetics with which I will be working and there is the question of space and feeding as to whether she would be worth it. She will not be ready to be bred until after next summer.
In the end, this kindle did not really answer my questions and even added more, but this is the fun part of figuring out rabbit genetics and breeding plans.