Effect Of Supplementing Urea, Probiotics And Enzyme Complex On Production Performance Of Laying Hens In Low Protein Diet

Experiment one Two hundred and twenty five 22-week old Roman laying hens were randomly divided into three treatments, consisting of 5 replicates of 15 birds per each. This study was carried out for 8 weeks to determine the effect of urea and oil on production performance, excreta crude protein contents and nutrient utilization in laying hens. Layers in the control fed the basal diet, layers in the U treatment fed the basal diet supplementing with 0.1% urea, and in the UO treatment fed the basal diet supplementing with 0.1% urea and 0.5% oil. The results showed that:1.Compared with the control, layers in the U treatment had lower egg production, tend to decrease the weight of egg and feed intake, and tend to be with poor feed conversion. Feed intake and egg production in UO treatment tend to be higher than that in U treatment. Feed conversion efficiency was not affected by treatments.2.U and UO treatment decreased the crude protein content in excreta. Compared with the control, layers in U and UO treatments tend to have a higher protein retention.In conclusion, supplementing 0.1% urea to the basal diet did not improve the production performance, which may be due to the poor balance between amino acids in basal diet. Although non-essential amino acids can be synthesized by supplementing urea, the production performance would not be improved as the deficient of essential amino acids.Experiment two Three hundred 22-week old Roman laying hens were randomly divided into four treatments, consisting of 5 replicates of 15 birds per each. This study was carried out for 8 weeks to determine the effect of enzyme and probiotics on the improvement of miscellaneous meal feed quality in laying hens. Layers in the control treatment (treatment A) were fed the basal diet, layers in the...