From a genetic standpoint, there may be one plus because such flocks seem to have a “survival of the fittest” condition when it comes to staying well and avoiding disease. However, what you lose in other traits may not make up for it.
If you’re breeding your own birds for meat or eggs, you do not have to meet someone else’s set standards or mandates. You are free to make that determination for yourself. However, by and large, one of the best things that you can do in your breeding program is to find a desirable body size and type that seems to get you the desired results. From a production standpoint, this is much more important than working on other traits.
Other than owning and raising bantams, most people will never deal with other dwarfing genes or factors. Most poultry owners know when you breed a bantam with a larger bird, the resulting offspring generally grow to be a size between the two parents. At one time, it was thought that there was one, incompletely dominant, dwarfing gene responsible for the smaller size in bantams. More recent research indicates that several modifying alleles, all working together, are more likely responsible for this trait.
One type of dwarfism that’s useful in the commercial meat bird industry is a sex-linked recessive dwarfism. While it is considered recessive, females, which have only one of the genes in their genetic makeup, are still about 32 percent smaller than birds that don’t have the gene. When bred to normal-size males, all of the offspring are normal size. This trait has been introduced in some broiler lines, to produce hens for breeding that consume less feed and can be kept in smaller enclosures. About 18 to 20 percent of the European meat bird industry now uses these hens. Because this type of genetic material is proprietary for industry, it is closely guarded, and it is unlikely that many people will be able to procure these birds for home breeding projects.
• Hutt, F.B., PhD., D.Sc., Genetics of the Fowl, McGraw-Hill Book Company, 1949. Jull, Morley A., Poultry Husbandry, McGraw-Hill Book Company, 1951.
• Wole A, et al., Genetic Parameters of Egg defects and Egg Quality in Layer Chickens, Oxford Journals, Science and mathematics, Poultry Science, vol. 91, issue 6, pp.1292-1298