Effect of low degree and high degree deacetylated chitosans in diet on performance, egg quality and functional egg feature of laying hens

Two experiments were conducted to evaluate whether dietary chitosan produced in different characteristics (minimum 70% or 90% deasetileted) would affect laying performance, egg quality, egg cholesterol, egg oxidant-antioxidant capacity, egg shelf life and some plasma parameters of layers. Thirty four weeks old laying hens were divided into 9 dietary groups of similar mean weight, comprising 14 birds each. The birds were fed standard layer diets containing 0, 200, 400, 800 and 1600 mg/kg low or high degree deacetylated chitosan for 8 weeks period. The birds were housed in individual cages in a complete randomized design. A 16:8 hours light:dark photoperiod was employed. Feed and water were given ad libitum. Laying performance was assessed by recording feed intake, egg weight, egg production daily; egg quality weekly. Egg cholesterol, egg oxidant-antioxidant capacity were assessed by weekly and the glucose, cholesterol and triglyceride concentration of the plasma were analyzed at the beginning and at the end of each experimental periods. Egg shelf life was analyzed at the end of experimental period. In experiment 1, the results showed that different levels of dietary low degree deacetylated chitosan did not have significant (P>0.05) effects on feed intake, feed conversion ratio, body weight, egg quality parameters, egg cholesterol concentration, egg yolk antioxidant capacity, plasma cholesterol, glucose and tryglyceride concentrations. However, low degree deacetylated chitosan decreased (P<0.05) oxidant capacity of yolk. Dietary supplemental (800 mg/kg and 1600 mg/kg ) low degree deacetylated chitosan improved egg shelf life stored at wholesaler or consumer conditions. In the second experiment, the results showed that high degree deacetylated chitosan supplementation did not have significant effects (P>0.05) on feed intake, egg weight, egg mass, body weight and egg quality, egg yolk cholesterol concentration, egg yolk antioxidant capacity, plasma cholesterol, glucose and tryglyceride concentration. However, dietary supplemental high degree deacetylated chitosan decreased (P<0.05) oxidant capacity of egg yolk, increased egg shell life stored in +4ºC. The results suggest ,regardless of the supplementation levels, high degree deacetylated chitosan may not improve performance, egg quality, egg cholesterol and plasma biochemistry of laying hens. These findings indicate the improvement tendencies (P=0.24) in egg shell life, egg oxidant capacity and egg cholesterol parameters of laying hens in treatment groups. As a result; 70% and 90% deasitiled chitosan could have a potential to produce the functional product in laying hen nutrition.