Indigo is a color modifier found in many pigeon breeds. Evidence indicates it originally came from the middle east. Even today, many breeds from that area show evidence of it in their phenotype. However, because indigo has varying expression depending up the base color, it wasn’t described as something genetically different until the mid-thirties. Wendell Levi and Willard F. Hollander, in unison, worked out the genetics of indigo. I’m not going to go into the now sixty year old history, but if you’re interested this effort is describe in Levi’s book, The Pigeon. Suffice it to say, though, that indigo was found to be non-sex linked dominant in its inheritance. It is not quite a simple dominant, however, and this is why it often goes unrecognized even in racing homers, where I’ve seen it in direct imports from top Belgian lofts.
Indigo in its heterozygous state (i.e., only one gene in the bird) is what many fanciers try to achieve because heterozygous indigo (het indigo) in combination with spread (think black for the moment) produces one of the most attractive of all pigeon colorations, Andalusian, so named for its similarity in color to the Andalusian chicken. It is a deep indigo blue coloration all over the bird. Better specimens - at least in shows - are often laced on each feather with a darker indigo blue coloration. (Homozygous indigo with spread gives something totally different, a light bodied pigeon with a darker head.) This andalusian color only shows up on a blue series pigeon (i.e., a blue barless/bar/check which also carries het indigo and spread. A bird in either of the other pigment series (brown or Ash-red) will not be andalusian even though it is spread and het indigo. In fact, indigo will be almost invisible on the bird. Ash-red indigos are fairly difficult to differentiate from simple ash-red birds -- though once one knows what to look for, it is sometimes possible to do so. Ash-red Indigos often show a more "purple" tint to the rump and head than do simple Ash-red birds. Brown indigos are simply sort of “yucky” looking.
If a bird in the blue series is not spread (black) but simply check or bar, het indigo is still obvious, but much less striking in its effects. Normally, the black tail bar is washed out, the checks and wing bar are changed to a bronzy indigo coloration and the blue body color tends to be a bit darker. (One of these birds crossed with a black will give you about 50% andalusian colored birds, depending on whether your black is heterozygous spread or homozygous spread.) So far, we’ve discussed het indigo, but what about homozygous indigo? What does it look like on the bird?
Homozygous means a bird carries two genes for the trait, rather than just one. Some people get confused here and believe female pigeons can’t be homozygous for any color modifying trait. That’s incorrect. Because indigo is non-sex-linked, both males and females may be homozygous for it. Homozygous indigo (homo indigo) produces not the andalusian colored bird, but rather an Ash-red mimic. I’ve seen examples that looked just like ash-red checks or bars. The only difference is that in homo indigo birds, the rump and neck is normally a darker indigo hue than is found in ash-red birds. Some, so much so that they are easily distinguished for what they are, others, however, are so close to Ash-red that breeding tests are about the only way to be sure what factor you’re dealing with. Often such ash-red mimics are mated to ash-reds and because indigo is near impossible to determine on the ash-red series, the mutation (indigo) is carried along hidden from the fancier’s view.
Quite likely, indigo entered racing pigeons from the early crosses in Belgium. Levi, in fact, discovered indigo in Carneaux, a pigeon whose ancestry is from the Belgian/French border area and stretches beyond that back to middle-age Syria and birds now called Lebanons. Indigo is still common in Lebanons and many Carneaux. Some of these birds were undoubtedly used in the creation of the modern racer and the indigo mutation carried along. One imported Janssen hen I’ve seen locally is an indigo bar (listed as brown on its pedigree). The European fancier sold it because it “was a funny color.” Don’t misunderstand me. Neither Belgian fanciers, nor those of the middle east are stupid pigeon people. Occasionally, they got what we today call andalusian-colored pigeons. They recognized them as something different and had various names for them. It was Levi and Hollander, though, who worked out the inheritance of the mutation and allowed us to create the andalusian color whenever we wished.
For anyone who wishes to add a touch of color to his flying loft, indigo is a fantastic modifier to work with. There are no drawbacks to it. By that, I mean, it’s not like almond or dominant opal which shouldn’t be mated to one another lest hatching suffer. Indigo to indigo matings merely produce ash-red mimics which can be mated to blacks to produce andalusians in quantity. Indigo is also “fairly” common in race birds now. It’s by no means something you find at every shipping, but a little hunting should allow you to find one to cross into your stud. Maybe someone in the Rare Color Racing Pigeon Club might have one to spare? Or someone in your own club? If you’d like to create those prettier laced andalusians, I’ve a little trick from one of the best show breeders in the world.
Once you’ve got your andalusian-colored pigeons, stop crossing them to black. Black, at least good colored black, has lots of “yucky” bronzes. These bronzes make the black shine like a crow, but they don’t do much for andalusian, creating instead a muddy coloration to the shield. Instead, cross the andalusian to T-pattern blues (i.e., what homer breeders in the U.S. call “velvets” or “blue-tailed” blacks.) I had planned to do that in my own loft, but, a few months back, my local Cooper’s hawk (Accipiter cooperii) decided an andalusian dinner was too good to pass up. She also likes blues, checks and splashes, by the way, so it isn’t just indigo which makes the birds a menu platter.
Copyright 1997 by Frank Mosca. This work may be downloaded or copied for non-commercial individual use only. All other rights under copyright are retained by the author.