effect of different levels of fennel extract and vitamin d3 on performance, hatchability and immunity in post molted broiler breeders

a 3 × 3 factorial experiment with three levels of fennel extract (fe) (0, 50, and 100 mg/kg of diet) and three levels of added vitamin d3 (vit d3) (0, 3500 and 4200 iu/kg of diet), was carried out to evaluate reproductive performanceand immune response of post molted broiler breeders(76-84 weeks).broiler breeders were weighed at 10 week after molting (74 weeks) then randomly distributed into 36 pens in order to have a similar mean pen body weight (bw). each pen consisted of 10 hens and 1 rooster. the birds received experimental diets at 74 weeks of age. performance data were recorded daily, whereas egg quality traits were determined every 4 weeks. to determine the settable hatch, fertile hatch, embryonic mortality, real hatch, chick quality, chick sexing, chick weight and relative chick weight, eggs from each pen were collected three times a week, marked and incubated in a commercial hatchery for 21 days. two blood samples were taken from two hens in each pen to assay newcastle and influenza antibody titers every two weeks.dietary fennel extract supplementation significantly increased egg production, chick quality and improved newcastle antibody titer over time (p