Head Points: Selecting for Head Shape Genetics Mini-Series Supplement #3 In the Genetics Mini-Series article #11, Breeding for Type, we discussed the importance of body shape for production characteristics such as egg laying and meat production. In this supplement, we will discuss the shape of the head and its role in breeding selection. In Walter … Continue reading
I wrote an explanation of skin and shank colors for GMS10: Skin and Shank Colors. I had so much material to cover that I did not include some basic Punnett Squares showing how white skin’s dominance over yellow skin plays out. You’ll want to go back and read GMS10 before proceeding if you haven’t seen … Continue reading
White and Recessive White Genetics Mini-Series Supplement #1 In this first supplement to the Genetics Mini-Series, we’ll look at the different genes behind white plumage and take a deeper look at the recessive white gene. Dominant white(I) is a gene related to dun and smoky (see below) which inhibits the black pigment eumelanin.1 Basically, it … Continue reading
Inbreeding Coefficients Genetics Mini-Series Article #12 Humans have been keeping fowl for more than three thousand years1. All of the varieties of chickens and other poultry we see today were created by men to serve their purposes by the process of selective breeding. These birds were the best fit, not for their natural environment, but … Continue reading
Breeding for Type Genetics Mini-Series Article #11 More important than egg color, feather color, shank color, or any other such decoration is type. Type refers to the general shape and conformation of the bird. However, type is not controlled by neat, Mendelian-type genetics which can be sketched out in a Punnett square. Body shape, including … Continue reading
Skin and Shank Color Genetics Mini-Series Article #10 Shank color genetics in chickens is anything but straight-forward. Traits believed to be dominant a century ago are now considered recessive. Traits which appear to be governed by one gene now appear to be one gene with five different loci. Some believe shank color to be controlled … Continue reading
Creating an Autosexing Breed Genetics Mini-Series Article #9 In the article on sex-linkage, we briefly looked at autosexing breeds. In these breeds, females and males look different as chicks. Autosexing is based upon the barring gene. One dose of the barring gene lightens a chick’s down slightly. Two doses lighten the down considerably. Using the … Continue reading
Check out the fantastic video about DNA on the Astronomy Picture of the Day website! Molecular Visions of DNA video Continue reading
Breeding for Two Traits Genetics Mini-Series Article #8 We discussed basic autosomal dominance back in article 2 of the genetics mini-series in the context of blue eggs. Using Punnett squares, we determined the probability that a particular offspring would inherit a certain trait, such as laying blue or white eggs. But suppose we want to … Continue reading
During the weekly genetic mini-series, we have discussed the basics of genetic inheritance in chickens. We first discussed egg color, introducing the idea of basic autosomal dominance (simple dominant and recessive) during our discussion of blue egg color. We then approached incomplete dominance as seen in blue feathering. After reviewing the basic mechanics of DNA … Continue reading
Scratch Cradle 