Abstract
•Dietary fenugreek, mung bean, and garden cress was investigated as natural feed additives for broiler chickens.•Low concentrations of fenugreek, mung bean, and garden cress had no negative effect on growth performance and carcass characteristics.•Increasing the dietary inclusion of seeds increased plasma concentrations of total protein and globulin.•Blood cholesterol concentration was affected by the interaction between seeds and the inclusion rate.•Dietary fenugreek, mung bean, and garden cress improved cell-mediated immune response.
The purpose of the present study was to evaluate the effect of different natural feed additive supplementation [fenugreek (FN), mung bean (MB), and garden cress (GC) seeds] on the growth performance, carcass characteristics, blood measurements, and immune response in broiler chickens. A total of 1,500 one-day-old unsexed broiler chickens (48.0 ± 0.5 g) were randomly assigned to 10 dietary treatments, each with 6 replicates of 25 broiler chickens. Broiler chickens were fed the control diets without any seeds and diets containing additives (FN, MB, and GC) at 0.5, 1.5, and 2.5% in a 3 × 3 factorial arrangement of treatments + 1 during the starter-grower (d 0 to 28) and finisher (d 28 to 42) phases. Increasing dietary supplementation of seeds percentages linearly decreased body weight (P = 0.001) and increased feed conversion ratio (FCR, P = 0.001). Greater dietary concentrations of FN reduced body weight and FCR. The inclusion rate of dietary seeds had a quadratic increase of relative weights of bursa of Fabricius (P = 0.04). Increasing the dietary inclusion of seeds linearly increased plasma concentrations of total protein (P = 0.04) and globulin (P = 0.003). Blood cholesterol concentration was affected by the interaction between seeds and the inclusion rate (P = 0.01). Cell-mediated immune response (phagocytes, T-lymphocytes, cytokines, etc.) at 24 and 48 h post injection of phytohemagglutinin-P tended to be greater (P = 0.06) in experimental groups fed a diet containing MB and GC compared with FN. It could be concluded that feed additive treatments might be involved in improving cell-mediated immune response and plasma concentration of total protein and globulin in broiler chickens. Dietary inclusion of FN at 1.5 and 2.5% concentrations must be avoided due to deleterious effect on growth performance.