Effect of Aloe gel on the performance and immune system of broiler

An Experiment was conducted to evaluate the effect of Aloe gel on the performance and immune responses of 240 day-old broilers cobb strain. Chicks were divided into six groups and each group into four subgroups on day 5 post hatch. The amount of zero (A0, control), 0.6 (A0.6).1.2 (A1.2), 1.8 (A1.8), 2.4 (A2.4) and 3mL/l (A3) Aloe gel were added to drinking water of each group up to day-42. Feed intake, daily live weight gain and feed conversion ratio were calculated every week. To evaluate cellular immune responses, 0.1=\ mL (0.2 mg/mL) phytohemagglutinin-p was injected intradermal in the skin fold of wings (day 16) and thickness of skin were measured after 24 and 48 hours. Sheep Red Blood Cell (SRBC) 25% (0.1 mL) were injected in the breast muscle in days 8 and 22 to investigate humoral immune responses, and IgM, IgG and total antibody against SRBC was determined in days 21, 28, 35 and 42 by agglutination test. Results indicated that the highest of feed conversion ratio (1.82) and lowest of live weight gain (53.94 g/day) were obtained from control during whole period (P