| Popis: |
The present study was conducted to evaluate the growth performance (from 1day to 6 week old), egg production (from 9 to 12 week of age) and egg quality in the Japanese quail (Coturnix coturnix japonica). A total of 300, 1-day-old Japanese quail chicks were used in this trial. Average body weight and feed intake at day 42 were 162 g and 553g/ bird, respectively, which corresponds to a feed conversion ratio of 3,59. At 8 weeks old, live body weight, body lenght, wingspan and chest width showed a significant sexual dimorphism in favour of females. The age of the quail at first egg was 49 days. Egg production was 52,1% corresponding to 14,6 eggs/quail. Average egg weight was 11,5g, while hatchability and viability were 84,5% and 76,5%, respectively. In terms of external and internal egg quality, the average egg weight was 11,5g while the shape index was 78,2. Eggshell weight, albumen weight and yolk weight were 1,47; 5,81 et 3,5g, respectively, correponding to proportions of 12,8; 50,3 and 30,4%, respectively. The mean value of Haugh units (UH), indicator of egg freshness was 57,4. Quails maintained at low density (20 birds per cage) had significantly highest egg weight and egg width than those kept at density of 25 birds per cage. The opposite has been observed in terms of UH and proportions of eggshell, albumen and yolk. Principal Components Analysis (PCA) with 9 egg quality traits revealed three principal components with eigen value higher than 1. PC1, PC2 and PC3 accounted for 44,3%, 14,2% and 11,9% of total variance, respectively, which correspond to a cumulative percentage of 70,5%. The last axis (CP3) is considered as a specific factor for the eggshell. |
