Use of molecular genetics in poultry breeding

TLDR: Potential utility, implementation, and limitations of MAS in poultry breeding are examined, including sex limited traits which can only be measured in one sex, and traits which cannot be measured on either sex, such as disease resistance or meat quality.

Abstract: INTRODUCTION Poultry breeding prior to this decade was based mainly on what could be observed or measured at the phenotypic level such as egg number, body weight, and egg weight. Unfortunately those types of traits are also influenced by random environmental factors such as feed quality, peck order, temperature, and disease. Clearly random environmental factors are a hindrance to breeding superior genetic stock. However, even greater problems are sex limited traits which can only be measured in one sex, such as egg production, and traits which cannot be measured on either sex, such as disease resistance or meat quality. In those cases the breeder must rely entirely on information from relatives to make selection decisions. The desire of poultry breeders has always been to get directly at the underlying genetic worth of the bird, free from environmental effects, and on all animals regardless of sex or ability to measure the phenotype. Now biochemical techniques allow scientists to probe directly into the genetic code of life. These advances would seem to provide the answer to selecting superior animals without complications of environmental effects, but as Bulfield (1998) questions, will these advances cause animal breeding to become a biotechnology or will it just be a passing fad ? The question most breeders are asking is how important are these advances to breeding and at what cost. In the following I will examine potential utility, implementation, and limitations of MAS in poultry breeding.