Abstract
The present study was conducted to estimate average weights, and corrlation and regression coefficients among various traits of eggs obtained from Korean native and imported chicken. Data were obtained from 360 layers (180 of Korean native origin, and 180 of imported Decalb Brown) between November 8, 1994 to February 8, 1995. The results obtained are summerized as follows : 1. The mean weights of whole egg, yolk, dense white, thin white, and egg shell of native chicken were lighter (P<0.01) than those of Decalb Brown. 2. The coefficients of variability in each egg trait were lower in native chicken than in Decalb Brown, indicating the higher ability of native chicken to adapt to the local environment. 3. The phenotypic correlation coeffcients between whole egg and weights of yolk, dense white, thin white, and eggshell were 0.842∼0.992(P<0.01) in native chicken, and 0.865∼0.985(P<0.01) in Decalb Brown. 4. The average eggshell thicknesses of native and imported Decalb Brown were 362.5 $\mu\textrm{m}$ and 407.9 $\mu\textrm{m}$, respectively. 5. The regression coefficients of most of the traits of eggs from native chicken were lower than those from Decalb Brown layers, suggesting that Korean native chicken should be improved further in various egg traits measured in this study.
본 연구는 한국 재래계의 난질 개량을 위한 기초자료를 얻고자 수행하였으며, 그 결과는 다음과 같다. 1. 재래계는 개량계(Decalb Brown)에 비하여 난중, 난황중, 농후난백중, 수양난백중, 난각중 등이 가벼웠으나(P＜0.01), 난중비는 차이가 없었다(P＞0.05). 2. 재래계는 개량계에 비하여 난각 형질에서 변이계수가 낮았으며, 이는 환경 적응성이 재래계에서 높음을 시사해 주고 있다. 3. 재래계와 개량계 공히 난중, 난황중, 농후난백중, 수양난백중, 그리고 난각중 간의 표현상관이 높았고(P＜0.01), 특히 재래계에서 0.842~0.992 로 높아서, 난중 개량에 의한 간접 선발의 효과가 클 것으로 기대되었다. 4. 난각두께에서 재래계와 개량계가 각각 362.5와 407.9 $\mu\textrm{m}$ 로서 차이가 있었다(P<0.01). 5. 재래계는 개량계에 비하여 난의 각 형질에서 회귀계수가 공히 낮게 나타나서 난중개량과 동시에 난각 형질의 개량이 요구되었다.