Effects of Dietary Supplementation with Peanut Skin and Bromelain on Egg Production, Blood Parameters and Liver Fat Accumulation in Middle-age and Aged Laying Hens

Background: This study examined the effects of a diet supplemented with peanut skin and bromelain on egg production, egg quality, blood parameters and fat accumulation in middle-aged and aged laying hens. Methods: In Trial 1, 120, 62-week-old Hisex Brown laying hens were grouped into five treatments: a control and high and low concentrations of peanut skin and bromelain groups. In Trial 2, 96, 93-week-old Hisex Brown laying hens were grouped into four groups: control, high concentrations of peanut skin and bromelain and a peanut skin and bromelain combination. Egg production and quality were monitored over an 8-w period and included egg weight, shell thickness and yolk color. Blood samples were analyzed for lipid profiles and liver function. Fat accumulation was observed in the abdominal cavity. Result: Egg production of hens receiving supplementation of peanut skin and bromelain improved substantially in 62-w-old hens (but not in 93-w-old hens) compared with the control group. Substantially reduced blood glucose levels and beneficial changes in yolk color were observed in the supplemented groups. The addition of peanut skin and bromelain to the diet positively affects the productivity and health of middle-aged laying hens.