Stimulation of growth and development in Japanase quails after oral administration of ecdysteroid-containing diet

Freshly hatched Japanese quails of the strain Faraon were fed for 50 days by diets containing graded amounts of pulverized seeds of an Asiatic plant Leuzea carthamoides Iljin. The dry seeds of this plant contained 1.8%-2.1% of 20-hydroxyecdysone, together with some smaller amounts of other ecdysteroids. In additional experiments the quails were also offered the standard diet plus whole seeds of Leuzea ad libitum and the standard diet enriched with certain commercially available biostimulating preparations for birds, Biostrong and Ecovit.The effects of the diets were evaluated first at the age of 37 days and then at the age of 50 days, which covered the reproduction period. Investigations related to the effects on growth, behaviour and overall developmental conditions were completed by RIA analysis of ecdysteroid concentrations circulating in the blood of the quails.The basic experimental series involved testing of the following diets: 0) Standard diet (SD); 1) SD + 0.2% Leuzea seed; 2) SD + 1.0% Leuzea; 3) SD + 5.0% Leuzea; 4) SD + 5.0% Biostrong; 5) SD + 3.0% Ecovit, and; 6) SD + the whole seeds of Leuzea ad libitum. At the age of 37 days we found the following percentage increase of the living mass (Control group = 100%): 1) 102.8%; 2) 109.5%; 3) 120.4%; 4) 101.9%; 5) 104.9%:, and 6) 103.5%. These results confirm previous findings of strong anabolic effects of Leuzea in growth of the vertebrate animals. However, since the plant contains a number of other biologically active classes of the secondary plant substances, the true responsibility of ecdysteroids for the described effects cannot be guaranteed, without further studies with pure ecdysteroid. The results of RIA analyses revealed that the amount of 20-hydroxyecdysone circulating in the blood of Japanese quails was directly proportional to the amount of dietary ecdysteroid. The largest concentrations, around 80 ng/ml of blood were found in quails which consumed the whole seeds of Leuzea.