Transport Stress and Alleviating its Effect by Supplemental Copper and Zinc in Laying Quails
This study was conducted to determine the effect of copper, zinc and their combinations on egg yield and reproductive performance of quails exposed to transport stress. In the study 80 day-old, 48 male and 144 female laying Japanese quails were randomly assigned to 1 control and 3 treatment groups, 3 replicates each consisting of 16 birds. The control group was fed a basal diet and the treatment groups were fed the basal diet supplemented with 150 mg of Cu kg-1 of (group I), 150 mg of Zn kg -1 of (group II), or 150 mg of Cu plus 150 mg of Znkg -1 (group III), during trial. The mean feed consumption (p<0.05), final live weight (p<0.01) and egg weight (p<0.01) of the control group were lower than the treatment groups after transportation. In all groups transport stress caused a sudden decrease of hen day egg production, which reached to the normal level at the 2nd week in groups I and III, at the 3rd week in group II and at the 4th week in control group after transportation. Hatchability of fertile eggs were significantly higher at the 2nd (p<0.01) and 3rd week (p<0.05) after transportation in treatment groups. However, embryonic mortality was not significantly different between groups. The results suggested that transport and different environmental stress were ameliorated by supplementation of copper, zinc or their combination.