Effect of dietary graded levels of dried lemon (citrus aurantifulia) pulp on performance, intestinal morphology, and humoral immunity in broiler chickens

Purpose Dried lemon pulp (DLP) is a by-product of fruitprocessing industry and is containing active antioxidantssuch as flavonoids, isoflavones, and flavones. Thus, currentexperiment was carried out to evaluate the effect of dietarygraded levels of DLP on performance, intestinal morphology,and humoral immunity in broiler chickens.Methods Accordingly, a total of 280-day-old broilerchickens (Ross 308) were assigned to 4 treatments and 5replicates of 14 chicks each. Dietary treatments includedcontrol (CON) with no additive as well as DLP1: 2.5, 5,and 7.5%; DLP2: 5, 7.5, and 10%; and DLP3: 7.5, 10, and12% in starter, growing, and finisher phases, respectively.Subsequently, performance, intestinal morphology, andhumoral immunity were evaluated throughout theexperiment.Results Body weight of chickens decreased when usinggraded levels of DLP during different periods of theexperiment as compared with CON (P.05). Also, dailyweight gain was lower in those supplemented by 7.5% DLPthan CON across finishing period (P.05). Therefore,feed conversion ratio of broilers was impaired when usinggraded levels of DLP across the entire production phasecompared to the birds in CON group (P.05). Antibodytiter against influenza disease virus and sheep red bloodcells decreased when using DLP3 and DLP2, respectively(P.05). Jejunal crypt depth decreased in chickens fedon DLP3 compared with control.Conclusion Dietary graded levels of DLP modifiedintestinal segments while deteriorated growth performanceof chickens. Furthermore, DLP3 decreased jejunal cryptdepth. Thereby, the use of DLP particularly at high levels isnot recommended.