Divergent Selection for Body Weight and Yolk Precursor in Coturnix coturnix japonica.: 8. A Summary of Correlated Responses

Abstract

Correlated response data accompanying 19 generations of selection for increased (HW) or decreased (LW) 4-wk BW and increased (HP) or decreased (LP) total plasma P were summarized. Similarly, 11 generations of selection of sublines derived from the original Lines HW and LP were also analyzed. Sublines were maintained through selection of males for increased 4-wk BW and females for the respective high or low plasma P.The randombred control (RBC1) was stable for BW early in egg production, BW change from early to late in production, wet and dry liver weights, 120-day egg production, and ova weight. A linear decrease in BW was found for the RBC1 line late in egg production, egg and respective component weights, and ova number. Body weight early and late in the production period for original Lines HW and LW was different from the RBC1 line. Wet liver weight increased for the HW line while dry liver weights declined in the original Lines LW, HP, and LP. Egg weights were greater in Line HW and lower in Lines LW, HP, and LP than in the RBC1 line. Yolk weight increased in Line HW and decreased in Lines LW and LP. Albumen weight was reduced in Line LP while shell weight was increased in Line HW and decreased in Line HP. Egg production, from onset to 120 days, decreased in Lines HW and LW when compared to the RBC1 line. Line LP had more follicles in rapid development than Line RBC1. The sublines responded similarly to their line of origin differing only in the magnitude of response. This was a reflection of the mating scheme, which placed selection pressure on BW of males and plasma P in females.