title: The effects of genetic selection on production parameters of single comb White Leghorn hens.
abstract: Four commercial table egg genetic stocks consisting of the Ottawa Control Strains 5, 7, and 10 (CS5, CS7, and CS10) and the 1993 H&N "Nick Chick" (CCS) were housed in the same environment and compared for production characteristics. These birds were housed in an environmentally controlled laying facility with trideck cages. Feed consumption, egg production, and mortality were monitored daily and compiled every 28 d. The study was conducted for two egg production cycles, including the molt period. Body weight was progressively lower for the more modern strains with CS5 being the heaviest and CCS maintaining the smallest body weight throughout the production periods. The CCS had the highest (P < 0.0001) hen-day production rate, which resulted in the greatest daily egg mass among the strains. The CCS consumed the greatest amount of feed and exhibited the highest gross egg income among the strains. We concluded that genetic selection has improved production parameters in commercial layers as determined by measurements in this study.
authors.affiliation: Department of Poultry Science, North Carolina State University, Raleigh 27695, USA.
authors.forename: D R
authors.initials: DR
authors.lastname: Jones
authors.forename: K E
authors.initials: KE
authors.lastname: Anderson
authors.forename: G S
authors.initials: GS
authors.lastname: Davis
mesh_terms: D000818:Animals; D001835:Body Weight / Q000235:genetics / Q000502:physiology; D002645:Chickens / Q000235:genetics* / Q000502:physiology; D004531:Eggs / Q000592:standards*; D002149:Energy Intake; D005260:Female; D006799:Housing, Animal; D010058:Oviposition / Q000235:genetics*; D012641:Selection, Genetic