Effect of chicory extract and Ultimate acid on performance, carcass characteristics and immune system of broiler chickens

The aim of this study was to evaluate the effects of an organic acid (Ultimate acid, UA) and chicory extract (CE) on performances, carcass characteristics and immune system of broiler chickens.Three hundred thirty oneday old broiler chicks (Ross 308, male and female) were allocated to the experimental units based on a completely randomized design using a factorial arrangement of 2 × 3 with two levels of CE (0 and 2 ml/Lit. of dinking water) and three levels of UA (0, 0.25 and 0.5 ml/Lit. of drinking water). Each treatment replicated 5 times with 11 chicks per replicate. Feed intake, daily body weight and feed conversion ratio were determined during the entire (0-42 d) experimental period. At the end of experiment (day 42), two chicks close to average body weight of each replicate were selected and slaughtered for carcass quality triats. Administration of UA alone significantly (P<0.05) reduced both feed intake and body weight gain compared to the control group but did not show any adverse effect on feed conversion ratio. Adding CE to drinking water increased gain in body weight and improved the relative weights of carcass and parts yield of the chicks compared to the control group (P<0.05). Main effects for CE and UA, and their interactions showed positive effect on immune reponse of broiler chicks measured by antibody titres against SRBC using agglutination test. In conclusion, the evidence of this study suggests the addition of chicory extract in the drinking water of broiler chicks as a growth promoter.