Effect of dietary supplementation with Gontscharovia popovii on growth performance, whole body composition, and hematological parameters in Litopenaeus vannamei

The study analyzed the effect of Gontscharovia popovii supplement on growth performance, whole body composition, and hematological parameters of Litopenaeus vannamei. The shrimp were fed with 0.5%, 1%, and 2% G. popovii powder for 45 days. The essential oil of G. popovii was analyzed and found to contain a total of 49 compounds. The main compounds identified in the oil were carvacrol, γ-terpinene, and (E)-caryophyllene. The highest activities of phenol oxidase and superoxide dismutase were observed in the control group (5.64±0.14 µg/mL) and 2% concentration (56.24±0.5 µg/mL), respectively. The hematological parameters indicated that the highest values of triglyceride (108±0.88 mg/dl), cholesterol (103.3±2 mg/dl), IgM (268.5±4 mg/dl), and hyaline (5.5±0.22 10^6 cell/mL) were observed in the 2% concentration. The highest amounts of hemocyte (1.22±0.01 10^7 cell/mL) and large-granular cells (2.3±0.05 106 cell/mL) were observed in the 1% concentration, while the highest amount of semi-granular cells (4.9±0.15 10^6 cell/mL) was observed in the 0.5% concentration. The results of digestive enzyme activities showed that the highest activities of amylase (1265.2±22.1 n/kg), lipase (57.1±2.7 n/kg), and protease (245.2±6.12 n/kg) were observed in the 2% concentration, respectively. The results of growth performance indices showed that the highest amounts of weight gain percentage (417.58±3.55 %), weight gain rate (12.5±0.03 g), and specific growth ratio (1.73±0.01 %/days) were observed in the 2% concentration, while the highest amount of food conversion ratio (1.46±0.02) was observed in the control group. Furthermore, the results of whole body composition showed that the highest level of crude protein (18.05±0.1 %), crude lipid (1.08±0.04 %), and moisture (4.7±0.15 %) were observed in the 2% concentration, while the highest level of ash (76.8±0.4 %) was observed in the control group. In general, the findings indicate a beneficial impact of dietary supplementation with G. popovii at 2% to improve blood biochemical and immune indices, digestive enzyme activities, and growth performance in L. vannamei.