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An Appearance of Abnormal Combs A Beginner’s Experience with the Unexpected By Scott Colomb February 8, 2013 Ignorant Bliss In April of 2012, I hatched chicks from Wheaten and Copper Black Marans eggs. At that time, my out-of-state work was extended through the end of the year and I ended up being away for as much as two weeks every month. As such, I never was able to spend enough time with the birds. Fast forward to January, 2013. With my background in conservation breeding of foreign pheasant species, I am quite capable of caring for and breeding birds. However, selection against anything other than evidence of hybridization or deformity is never done in conservation breeding, so selecting toward a poultry standard is something I had never done. I felt quite unsure of myself and kept putting off any culling. I had five wheaten cockerels with four pullets, and ten copper black cockerels with eight pullets. In January, they were 9 months old and eating me out of house and home. I could not put off culling any longer and cockerels seemed like a good place to start. One of the workers at my local feed store was willing to take my cockerels, and I was happy to give them to him. However, he could only take them three at a time. After he processed them over the weekend, he could take three more the next Thursday, and so on. I began by culling cockerels with what I thought were obvious faults. Two wheaten cockerels were culled for color on their flanks and one copper black had a side sprig on each side of the blade of his comb.That brought me to three culled cockerels, so I stopped. The next week, I picked out three more. One copper black had a sprig along the center of his comb and two had a sprig on each side in the comb blade. The next week I culled another wheaten cockerel I didn’t like and pulled one copper black I didn’t like and another that had a sprig on each side of his comb blade. I was now left with two wheaten cockerels that I liked and four copper blacks. Two of these copper black cockerels I liked. Another had some really good qualities, but his color was off. The fourth wasn’t bad, but had a sprig on either side of his comb blade. He would have to go. I wasn’t ready to go to the feed store, so I decided to go through my pullets. I started with copper blacks and the first one I pulled had a sprig on each side of the comb blade. With the cockerels I didn’t really think much about the sprigs, because it made it easy to decide which ones to cull.... even though some of them were nice birds. However, with the pullets I was disappointed to find such a fault in the very first one I pulled. I consigned her to the “cooking egg flock”. I pulled the next pullet and found the same thing. Out of the eight pullets, five had a similar defect, ranging from one sprig on the blade to one sprig on each side of the blade, symmetrically opposing each other. This was quite similar to what I was finding in high percentages on my cockerels. I checked my four wheaten pullets. One had a tiny, thin sprig at the base of the center of her comb, another had one sprig similar to the copper black pullets on the blade of her comb. The other two pullets were clean. This was quite disappointing and it got me to thinking. With the exception of one copper black cockerel and one wheaten pullet, both of which had a sprig on the center of the comb, all other sprig-affected birds had a similar situation with sprigs in the comb blade. Of those, most had two sprigs symmetrically opposing each other. This could not be a chance occurrence because it seemed to be a pattern. The Search For An Answer My use of words such as “sprigs” and “blade” might sound intimidating. I must admit that these terms were new to me when I began culling through my birds. I had heard about “sprigs” a few weeks before and had to do a google search to find out exactly what they are. Rather, what I thought I understood them to be. As it turns out, for such a common occurring fault in chickens, there does not seem to be a lot of sure or proven information about them. Marans should have a single comb, which is composed of the comb base, Point Point points, and a blade at its rear. The comb should be straight, erect, and Point Point smooth, with five or six distinct and deeply serrated points. Ideally, the blade Point should be smoothly rounded, without any Base Blade points. Other than the five or six points, the comb should be free of any other bumps or protrusions. Though not meeting the Sprig Standard, it is not hard to find birds with Sprig more than 6 points on their comb. It is also not hard to find birds with bumps, points, or protrusions on the side of the comb base or blade. These are typically called “side sprigs” and are a genetic trait that can be Anatomy of a Single Comb passed on to future generations. They are also a disqualification in all single-combed breeds, with the exception of the Penedesenca. In the Penedesenca, the sprigs are not only allowed, but are Side Sprigs required as long as they specifically form a swirl at the back of the blade. This formation is called a “carnation comb” or “king’s comb”. Pullet - from above Rooster - side Rooster - front Rooster - rear In form of a cup Examples of Carnation Comb Expression As Seen in the Penedesenca In order to better understand what I was dealing with, I began searching on the internet for “side sprigs” and found various pictures. Though all texts stated that sprigs could occur anywhere along the comb, most of the pictures showed them in the blade of the comb. At this time, I was unaware of the “carnation comb”, but some of these pictures I was seeing mentioned carnation comb and looked similar to what I was experiencing. Further, some of these supposed carnation comb pictures were part of discussions about marans. The story behind these pictures is that breeders were having carnation combs suddenly appearing in their marans offspring. Supposedly, in the past penedesencas where crossed into marans in an effort to darken the marans eggs. I’ve been told that the penedesenca, whose egg color is actually more of a terracotta color, not only did not darken the marans egg, but left the marans with carnation combs and white ear lobes, both of which are genetically multi-factoral and difficult to breed out. The appearance of carnation combs is not limited to birds in North America. From what I have read, it seems to also be a problem in European stocks. So, what was going on with my birds? All of my investigation on the web provided no further clarity on the situation as there seems to be a lot of confusion between “side sprigs” that are located on the comb blade and “carnation comb”. As for the genetic basis, there doesn’t seem to be any real understanding of the causes or inheritance of either fault. I have seen reports that carnation comb is controlled by two recessive alleles, which both must be present for its appearance. Other reports add that it may additionally be controlled by unknown modifiers. Another report questions whether the incomplete dominance of the duplex comb gene may be responsible. I read one comment that carnation comb is a simple dominant trait, but from what I see that can’t be possible. Sprigs, on the other hand, have been variously reported as dominant, recessive, or double factor recessive. Logically, since they can pop up in almost any location and take on various shapes, I tend to think they are affected by multiple modifiers or other genes. I have also seen it questioned whether carnation comb simply being sprigs with selection for very specific modifiers governing location and shape. In the end, I’m now educated enough to know I still don’t know much about sprigs or carnation comb. Reconciliation I spoke with the person from whom I purchased my eggs. I consider him an open and honest friend and mentor. Not only is he experienced with marans, but he is knowledgeable of penedesencas. He has never crossed penedesencas into his birds and has never knowingly brought crossed birds into his flocks. He has never had carnation combs appear in any of his birds. He has selected against sprigs over the years and has not had major issues with that fault in his birds. As a simple recessive trait, you would expect that carnation comb would occasionally appear over time in a flock, which did not happen in his flocks. If, however, carnation comb is controlled by two different recessive alleles, then it is possible that a flock, or even multiple flocks within a particular line, could carry ONE of those recessive alleles and not ever show any sign of carnation comb. It is also possible that another flock, or multiple flocks within a particular line, could carry the OTHER recessive allele and never show any sign of carnation comb. Then, it would seem that crossing those two flocks or lines could lead to the sudden appearance of carnation comb. However, this scenario would still require two generations before appearing. If my birds have carnation comb, and I say IF because of all the confusion over what exactly is the difference between carnation comb and sprigs, then it is possible that my birds could be the result of the merged lines hypothesis. As it turns out, at least some of my copper black eggs were likely from one of my friend’s pens sired by a newly acquired rooster, who did not show any sign of carnation comb. However, this rooster was not from the same line as the hens. It is possible (but not proven) that merging these two lines led to the appearance of my comb abnormalities. However, my birds are the first generation sired by that rooster and as a double allele recessive the trait should not have appeared yet. Unfortunately, my friend did not hatch any eggs from this mating for himself last year, so my birds are the only possible examples of their offspring. Further, that rooster did not last long and is no longer available for examination or testing. On the other hand, if sprigs are controlled by modifiers or other factors that my friend has selectively bred to produce birds that either don’t have sprigs or the sprigs are not expressed on the comb, then it is also possible that the addition of this rooster from an unrelated line could have added factors that allowed the expression of sprigs. This begs the question, if there is a gene that inhibits the expression of the comb (Breda - Br), is it possible there is a gene or modifier that inhibits the expression of sprig? Further, it is not out of the realm of possibility that if sprig location and size could be controlled by specific factors, then this new rooster could have contributed factors that produced offspring with sprigs only in the patterns seen in my birds. Again, I am left with no surety of what is happening with my birds. Acceptance I do have two pair of wheatens and four copper black cockerels and three pullets, none of which show any sign of sprigs or carnation comb, to possibly work with this season. The dirty truth is I am also left with one copper black cockerel and three pullets with opposing sprigs on their comb blades and two copper black pullets with a similar, but less extensive, fault exhibiting only one sprig on the blade. Additionally, I have one wheaten pullet with a tiny sprig midway along her comb base and one wheaten pullet with what appears to be a sprig on one side of her blade. I say it appears to be a sprig because, though it is quite similar to the sprigs of the lesser affected copper blacks, it appeared in only one bird and I have a hard time reconciling how it could have otherwise suddenly showed up in the closed wheaten flock. I will say that my friend looked at the affected birds and commented that, in his experience, some of the situations looked like sprigs, but at least one did strongly resemble carnation comb. However, with the lack of understanding of either trait, who can say for sure. It is possible that carnation comb could be fully expressed as is seen in penedesencas, but maybe also as a partial expression as is seen in some marans. The only thing I know for sure is this is what the abnormal combs in my birds look like. Examples of Abnormal Combs Appearing in My Flock Copper Black Marans Cockerel In this cockerel, the only one remaining with a comb abnormality, two opposing protrusions appear on either side of the rear of the comb blade. These protrusions are slightly flattened similar to wings, except turned nearly vertical instead of flat. While this appears similar to the “swirl” of carnation comb, it does not produce the cup-effect often seen in the complete carnation comb. Comb Protrusion Comb Protrusion Comb Protrusions Copper Black Marans Pullet The comb of this pullet strongly resembles a carnation comb. The additional points are opposite each other on the top rear of the blade and are interconnected at the base of each point such that a cup is formed in the space between them. Copper Black Marans Pullet This pullet exemplifies the comb abnormalities exhibiting only one additional point. Though the size of the point varies between birds, the shape tends to be pointed, but widening at its base. These points are more flag-like and tend to extend generally in line with the comb, rather than projecting out from it. In the side view, the shape of the point can be seen in its shadow cast on the comb. Wheaten Marans Pullet I consider this comb abnormality to be a sprig because of the low incidence in this wheaten line and due to my inability to determine a way carnation comb could have recently entered this line. This flag-like sprig is very similar to the single-occurring point in the copper black pullets, which may indicate that both incidences may be side sprigs and not carnation comb. Cup Comb Protrusion Comb Protrusion Comb Protrusion Comb Protrusion Moving Forward While I would like to breed my birds that appear clean, it is possible that they carry the alleles necessary to again produce this comb abnormality. As detrimental as it is, I do not wish to allow it to remain within my birds going forward. I will only breed these birds if I can prove they do not carry the alleles to reproduce the trait. If it is recessive, either single (doubtful) or double allele, or as a result of modifiers, I should be able to determine whether my birds are carriers by test breeding them to birds that are known carriers. If any abnormal-combed offspring are produced, it can be assumed that the single-combed bird is a carrier. If only single-combed offspring are produced (though they should still be carriers), it can be assumed that the singlecombed parent MAY be free of tainted genes. It is possible that alleles could still be present that will allow the trait to reapper in future generations. In reading other people experiences, I came across a tongue-in-cheek response from one breeder who was dealing with this issue. Her comment, made in jest, was that it would be much easier if we just culled for single comb and selected for carnation comb. I am an optimist. I want my nicest single-combed birds to test “clean”. But, this opens my breeding to future disaster should these abnormalities reappear. The truth is I may be better off culling them all and starting over, but the optimist will not let me do that. Instead, part of me hopes that are found to be carriers... absolving me of the regret of culling them all and starting over, But for now, all I can do is move forward.