Abstract
A total of two hundred four one day old Ross broiler chicks were randomly allotted into four dietary treatments floor pen groups (17 birds/ pen, 10 birds/m2) with three replicates for each treatment. The dietary treatments were designed to feed the chick's basal diet supplemented with graded levels of Moringa oleifera leaves meal, MOLM [3%, 5%, 8% and 0% (control) MOLM]. Behavioral observation was carried out twice daily (AM and PM) two days a week for 6 consecutive weeks. Body weight (BW), Body weight gain (BWG) and Feed intake per pen was measured weekly, from which feed conversion ratio (FCR) was calculated. At 30th day of age blood samples were collected to evaluate anti body titer (HI) against New Castel Diseased Virus (ND). At the end of the experiment, fear responses, differential leucocyte count, Hb and PCV were assayed as well as some carcass traits. Also, dead birds were recorded. The obtained results showed that higher proportion of birds were engaged in feeding behavior in birds supplemented with 3% and 5% MOLM compared to the control one, with birds supplemented with 8% MOLM were intermediary but not different from them. Birds in control group were exhibited significantly higher walking and standing activities compared to birds fed MOLM groups. Dietary supplementation with different levels MOLM significantly improved BW, BWG and FCR. Dietary supplementation had no effect on percentage of birds died. Chicks fed basal unsupplemented diet were more fearful in TI test, more stressed and had a significant increase in heterophil/ lymphocyte ratio when compared with those supplemented with MOLM. MOLM had no effect on Hb concentration and carcass traits measured in this trial. PCV was significantly higher in birds fed 5% MOLM compared to control birds. Birds fed 3%, 5% and 8% MOLM had significantly higher antibody titer against ND compared to birds fed control diet. In conclude, dietary supplementation of broiler chicks with MOLM up to 8% resulted in improved welfare, performance and immune response against ND.

Key words: Broilers; Moringa; Oleifera, Behavior; Performance; Fear, Stress; Immune response.