Erdaw Weldes - Animal Feed Processing, Ethiopia Meat and Dairy Industry Development Institute, Ethiopia.
Meseret Girma - Animal and Range Science, Haramaya University, Ethiopia.
Mengstu Urge - Animal and Range Science, Haramaya University, Ethiopia.
Ali Beker - Animal and Food Science, Oklahoma State University, Ethiopia.

The feeding trial was conducted to evaluate the effect of thyme leaf as an additive on productive performance and egg quality traits of white leghorn chicken at Haramaya university poultry farm for ۱۱ weeks. One hundred twenty white leghorn (WLH) layers at the age of ۲۶ weeks with average initial body weight of ۱۲۱۶.۱±۶.۶۲ gram (mean±SD) were randomly allotted to four dietary treatments. The treatments were T۱ (Layers ration (LR) with ۰% Thyme leaf meal (TLM), T۲ (layer’s ration with ۱% TLM), T۳ (layer’s ration with ۲% TLM) and T۴ (layer’s ration with ۳% TLM). Each treatment group was replicated three times with ten laying hens and two cocks per replicate in completely randomized design (CRD). Samples of feed ingredients, thyme and formulated diets were subjected to chemical analysis before the actual experiment began. Weight of experimental birds was measured at the beginning and at the end of the experiment. The result indicated inclusion of thyme leaf in the layers diet significantly (p<۰.۰۱) influenced feed intake, final body weight, body weight change and average daily weight gain of birds which were greater in T۲ and T۱ than T۴. The hen-day egg production ۵۷.۲۰±۱.۰۹ in T۳ and ۵۹.۲۳±۱.۰۹ in T۴ were significantly (p<۰.۰۱) higher than birds in T۲ and control groups. The feed conversion ratio differs significantly (p < ۰.۰۱) among treatments ranging ۳.۲۸ to ۴.۷۰ and the lowest value was recorded in T۳ and T۴, which is an indicator of the best performance of birds. Among egg quality traits, yolk height and index were significantly higher in birds under T۲ and T۳ thanT۱ and yolk weight was higher in T۳ than T۱. The economic analysis showed that the total and net return of birds fed a diet supplemented with thyme is higher than birds fed the control diet. Therefore, thyme leaf can be an imperative feed additive that can be added up to ۳% in the layer ration to improve the performance of layers without adversely affecting product quality.The feeding trial was conducted to evaluate the effect of thyme leaf as an additive on productive performance and egg quality traits of white leghorn chicken at Haramaya university poultry farm for ۱۱ weeks. One hundred twenty white leghorn (WLH) layers at the age of ۲۶ weeks with average initial body weight of ۱۲۱۶.۱±۶.۶۲ gram (mean±SD) were randomly allotted to four dietary treatments. The treatments were T۱ (Layers ration (LR) with ۰% Thyme leaf meal (TLM), T۲ (layer’s ration with ۱% TLM), T۳ (layer’s ration with ۲% TLM) and T۴ (layer’s ration with ۳% TLM). Each treatment group was replicated three times with ten laying hens and two cocks per replicate in completely randomized design (CRD). Samples of feed ingredients, thyme and formulated diets were subjected to chemical analysis before the actual experiment began. Weight of experimental birds was measured at the beginning and at the end of the experiment. The result indicated inclusion of thyme leaf in the layers diet significantly (p<۰.۰۱) influenced feed intake, final body weight, body weight change and average daily weight gain of birds which were greater in T۲ and T۱ than T۴. The hen-day egg production ۵۷.۲۰±۱.۰۹ in T۳ and ۵۹.۲۳±۱.۰۹ in T۴ were significantly (p<۰.۰۱) higher than birds in T۲ and control groups. The feed conversion ratio differs significantly (p < ۰.۰۱) among treatments ranging ۳.۲۸ to ۴.۷۰ and the lowest value was recorded in T۳ and T۴, which is an indicator of the best performance of birds. Among egg quality traits, yolk height and index were significantly higher in birds under T۲ and T۳ thanT۱ and yolk weight was higher in T۳ than T۱. The economic analysis showed that the total and net return of birds fed a diet supplemented with thyme is higher than birds fed the control diet. Therefore, thyme leaf can be an imperative feed additive that can be added up to ۳% in the layer ration to improve the performance of layers without adversely affecting product quality.

Egg quality, Layers, Productivity, Ration, Thyme leaf