Effect of dried Citrus sinensis peel on gastrointestinal microbiota and immune system traits of broiler chickens

Two hundred broiler chickens (Ross-308) were used in a completely randomised study to evaluate the effects of supplementing the feed with different levels of dried Citrus sinensis peel (DCSP) on the gasrointestinal microbial population and immune system traits. Feed was supplemented with different DCSP amounts: 0.25% w/w (DCSP-0.25), 0.5% w/w (DCSP-0.50), 0.75% w/w (DCSP-0.75), and 1% w/w (DCSP-1). Control diet (DCSP-0), with no feed additition was used as reference. The study involved five treatments in a time frame of six weeks (four replicates per treatment and each replicate had 10 chickens). Data analysis was performed using SAS software and mean comparison was performed using the Duncan test. The results allowed to observe that the mean of Escherichia coli in caecum on day 42 was significantly different (P<0.05) but did not affect other gastrointestinal microbial population traits (P>0.05). The mean of total sheep red blood cells and immunoglobulin G and M (IgG and IgM) on day 28 (P>0.05) were also determined. Total sheep red blood cells on day 42 were significantly different (P<0.05). The IgG and IgM mean titers on days 28 and 42 was of no significant difference (P>0.05). Supplementing the feed with Citrus sinensis had no significant effect on Newcastle disease on day 42 (P>0.05). The mean value for hemagglutination inhibition on day 42 was significantly different (P<0.05). It can be then concluded that DCSP feed supplemention ameliorated the gastrointestinal microbiota and immune system traits.