Incidence of Double Yolked Eggs in the Initial Stages of Lay as Affected by Strain and Season of the Year

Abstract Data from seven laying trials were summarized to determine the influence of strain and season on the incidence of double yolked eggs in the initial stages of lay. At least 12 strains were studied during each of these trial-year periods. All birds were grown under natural daylight conditions and subjected to 14 hr per day including morning supplemental light (Trials 1 to 4) or 15 hr per day with morning and evening supplemental light (Trials 5 to 7) in the laying house. There were significant strain effects on the incidence of double yolked eggs at the onset of lay. This indicated possible genetic differences among strains for this characteristic. Spring and summer housed laying hens produced a greater number of double yolked eggs than did those hens placed in the laying house in the late fall or winter months. Incidence of double yolked eggs and age at 50% production were significantly correlated; however, this was believed to be a season rather than a within-strain maturity effect.