Productivity of selection for body weight at different ages in Japanese quails

ABSTRACT MSc THESIS PRODU CTION OF- SE LETCT ION FOR BODY WEIGHT AT DIFFERENT AGES IN JAPANAESE Mikail BAYLAN DEPARTMENT OF ANIMAL SCIENCE INSTITUTE OF NATURAL AND APPLIED SCIENCES UNIVERSITY OF ÇUKUROVA Supervisor: Prof. Dr. A Nazım ULUOCAK Year: 1998, Pages:74 Jüri: Prof. Dr. A. Nazım ULUOCAK Prof. Dr. Ahmet TESTİK Doç. Dr. Zeynel CEBECİ This study is conducted to examine the effects of mass selection implementation on offspring and parent generations of Japanese Quails (Coturnix coturnix japonica) according to body weights at different ages. At 3., 4. and 5. th weeks of ages, mass selection was applied according to the highest body weight for two generations. At the generation, egg yield and variation in egg weight for parent and fattening and carcass characteristics in the offspring of first generation are examined. For the selected lines at 3., 4. and 5. th weeks of age, the live weight gains are determined to be -2.72, 5.89 and 8.78 g for 1. generation, 1.03, 0.7 and 5.8 g for 2. generation respectively. The heritability with the same age order is found to be -0.28, 0.33 and 0.37 for 1. generation; 0.06, 0.03 and 0.27 for 2. generation. Although, there is not any significant differences between selected groups in both the two generations, a decrement in age weight but an increment in egg yield are observed in the whole selected groups in the second generation. Egg yield for the group selected in 5 th week of age is found to be higher in both the two generations. Feed efficiency rate for the offspring of first generation in 6 week fattening period is found to be 3.36, 3.05 and 2.95 respectively. As a result, selection according to 5.th week body weight is resulted better than selection at 3 and 4.th week body weight. Key Words: Quail, Mass Selection, Age, Body Weight, Egg Yield. n