The effect of vitamin E on cellular immune responses in laying hens forced-moulted by different methods

The aim of the study was to investigate the effects of vitamin E on the cellular immunity in laying hens induced by two different moulting programs. One hundred and forty four Isabrown hens 72 weeks of age were divided into six treatment groups: FAST group was moulted by fed withdrawal for 10 days; FAST+WE group was moulted by feed withdrawal for 10 days and feed with vitamin E supplemention (200 mg/kg) thereafter; Lo Na group was fed the full layer ration containing 0.08% sodium for 41 days; Lo Na+VE group was fed the full layer ration containing 0.08% sodium for 41 days with vitamin E supplementation (200 mg/kg), and two control (CON FAST and CON Lo Na) groups were feed the full layer ration. Plasma samples were collected from the hens in premoult, moulting I, II, postmoult I and II for determinating the plasma vitamin E levels, total and differential leukocyte count, and the delayed type hypersensitivity