Effects of the plant extract YGF251 on growth performance, meat quality, relative organ weight, nutrient digestibility and blood profiles in broiler chickens: possible role of insulin-like growth factor 1

This study was aimed at evaluating the effects of different concentrations of the dietary plant extract supplement YGF251 (young growth factor) on growth performance, blood profiles, relative organ weight, nutrient digestibility and meat quality in broiler chickens. A total of 640 one-day-old male Arbor Acres broiler chickens with an average initial body weight of 40.25 ± 0.5 g were randomly allotted to one of four treatments lasting four weeks with 10 replicates per treatment and 16 chicks per replicate pen. Dietary treatments consisted of: CON (basal diet); YGF0.05 (CON + 0.05% YGF251); YGF0.1 (CON + 0.10% YGF251); YGF0.15 (CON + 0.15% YGF251). There were no statistical differences in body weight (BW), feed intake (FI) and feed conversion rate (FCR) throughout the whole experiment. However, broiler chickens fed with YGF0.1 diets had greater body weight gains (BWG) than chickens fed CON diets during eight to 28 days and zero to 28 days although the means of pH value, breast meat colour, WHC, drip loss, the relative organ weights of liver, spleen, bursa of Fabricius and breast muscle were not affected by any dietary supplementation (P > 0.05). The relative weight of abdominal fat in the CON treatment group was significantly higher than the YGF0.05 and YGF0.1 treatments, although relative gizzard weight was lower with CON treatment compared to YGF0.1 treatment (P < 0.05). Femur length and weight were significantly higher in the YGF251-supplemented chicks than in chicks fed the control diet (P < 0.05). Broiler chickens fed the YGF0.1 diet had significantly higher blood IgG counts compared to chicks fed the CON and YGF0.05 diets (P < 0.05). Moreover, YGF251-supplemented chicks exhibited increased IGF-I concentrations compared to the CON to YGF0.1 treatment (P < 0.05). The results of this study indicate that supplementation with 0.1% YGF251 can increase body weight, IgG and energy digestibility and reduce relative abdominal fat and gizzard weight in broiler chickens, while at all concentrations tested YGF251-supplemented chicks showed higher results for femur length and weight and serum IGF-I concentrations compared to the control treatment in broiler chickens.