The Effects of Different Levels of Grass ClippingWaste on Performance, Egg Traits and Blood Parameters of Laying Hens

Abstract

In this experiment 144 Hy-line (W36) laying hens, 65 to 77 weeks of age were separated into 4 treatments with 3 replicates (12 birds per replicate) in a completely randomized design experiment. The grass clipping wastes incorporated into a complete formulated layer diet, consisting on a corn and soybean based diet, were 0, 1.5, 3.0 and 4.5% in 1 to 4 experimental groups. The results showed that using different levels of clipping waste significantly affected the performance, egg traits, blood biochemical parameters and immune cells of laying hens (P<0.05). The highest amounts of egg mass, feed intake, percent of egg production, the best feed conversion ratio, the lowest feed price for per kilogram of egg production and the highest egg yolk color index were obtained when using 3% of clipping waste. Despite this, the highest amounts of egg weight and egg specific gravity, the highest percentages of egg albumin and red blood cells were observed by using 4.5% of clipping waste. The highest level of blood HDL and percent lymphocyte and the lowest ratio of lymphocyte / heterophil were obtained using 1.5% of clipping waste. The overall results indicated that in laying hens, using clipping waste up to 3.0% of diets, significantly improved their performance, egg traits, blood biochemical parameters and immune cells. However, using 4.5% of clipping waste compared with control group, not only did not have any adverse effects on noticed parameters, but also improved them.