Investigation on main and interaction effects of Ultimate acid and chicory extract on performance and some immune system parameters in broiler chickens

The aim of this experiment was to evaluate the effects of Ultimate acid (UA) and chicory extract (CE) on performance, immune system and lymphoid organs (thymus, spleen and bursa of fabricius) of broiler chickens. Three hundred thirty one-day 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 chicory extract (CE, 0 and 2 ml/1 liter of water) and three levels of Ultimate acid (UA, 0, 0.5 and 1 ml/1 liter of water). Each treatment replicated 5 times with 11 chicks each. Antibody titer against NDV was determined by HI assay. On day 42 from each replication 2 chickens slaughtered and lymphoid organs separated and weighted. In spite of non-significant effect of UA supplementation on feed conversion ratio (FCR), its effect on both daily feed intake (DFI) and daily weight gain (DWG) (P