Effect of dietary vitamin D3 levels on reproductive parameters in Japanese quail

The presence of vitamin D3 in eggs is important for calcium metabolism of embryo and its development. This research was conducted to evaluate the effect of dietary vitamin D3 levels of 0, 1000, 2000, 4000 and 8000 IU/Kg on reproductive characteristics of Japanese quail. 320 adult Japanese quails were used in a randomized complete block design with five treatments, four replicates containing 12 females and four male birds in each replicate. After six weeks of feeding with experimental diets, 40 eggs from each replicate were transferred to a hatchery machine. After incubation, reproductive parameters were investigated. On day 42 of the experiment, two male and female birds from each replicate were selected to measure the blood sere testosterone and estrogen levels. Fertility, total hatch and weight of hatching chicks were not affected by vitamin D3 (P>0.05). The lowest (79.75%) and the highest (90.53%) hatch of fertile eggs were recorded in diets without vitamin and containing 1000 IU/Kg of vitamin, respectively (P<0.05). The highest early and total embryonic mortality were related to zero level of vitamin and the lowest losses were belonged to 1000 IU/Kg of vitamin. The mid and late embryonic mortalities were not influenced by treatments (P>0.05). The morphometric characteristics of reproductive system in both sexes and blood sera estrogen level in female birds were not differ (P>0.05). The highest sera testosterone concentration (11.05 ng/ml) was observed in 1000 IU/Kg of vitamin (P<0.05). In conclusion, the use of 1000 IU/Kg of vitamin D3 in Japanese quail diet is recommended for the best reproductive performance.