Effect of nettle (Urtica dioica) leaf powder on performance, carcass traits and immune responses in broilers

Nettle is medicinal plant with antioxidant, anti-microbial and anti-inflammatory properties and can be an alternative to antibiotics in poultry diets. The aim of this study was to investigate the effect of different levels of leaf powder of Urtica dioica L. on performance, carcass traits and immune system in broilers. One day old broiler chicks (200 Ross 308) were divided into 5 treatments with 4 replicates and 10 chickens per cage. The treatment groups received 0 (control), 0.5, 1, 1.5 and 2 percent dietary Urtica dioica L. leaf powder, respectively during days 0-42 in starter, grower and finisher diet. Daily feed intake, daily body weight gain and feed conversion ratio (performance) were measured.The birds were immunized with sheep red blood cell (SRBC) on days 8 and 22 of age and serum antibody levels produced in response to SRBC were measured on days 21, 28, 35 and 42. Skin response to Phytohemagglutinin-P (PHA-P) injected intradermally on day 16 was measured. The weights of carcass components and bursa of fabricius and thymus were measured after slaughter. The results indicated that 2% powder increased body weight gain and reduced feed conversion ratio in finisher and entire period compared to the control group (P<0.05). Bursa of fabricius weight was increased with consumption of 1.5 and 2% powder and thymus weight was increased with consumption of 1, 1.5 and 2% powder in comparison to control group (P<0.05).The inclusion of 1.5 and 2% powder to diet increased total anti-SRBC and IgG titer on days 28, 35 and 42 (P<0.05). One, 1.5 and 2% leaf powder increased cellular immunity on PHA-P injection (P<0.05). It is concluded that 2% nettle leaf powder increased performance, cellular and humoral immunity of broilers.