Effect Of Chinese Medicinal Feed Additive On Feeding, Growth And Non-Specific Immunity In Turbot (Scophthalmus Maximus L.)

Five diets were formulated with different Chinese Medicinal Feed Additive(CMFA) levels (0,0.5%,1.0%,1.5%,2.0%)and were fed to Turbot. The growth experiment and the biochemistry experiment were conducted to investigate the effect of CMFA on feed consumption, growth, digestibility to nutrition, activity of digestive enzymes and Non-Specific immunity in Turbot. The main results and conclusions were shown as following:1. There were no significant differences in the feeding rates of Turbot among different CMFD levels. But there were significantly differences in the weight gain (WG) and the specific growth rate (SGR).The WG and the SGR of turbot fed the diet contain 1.0% of CMFD is highest.2. There were no significant differences in feed digestibility in Turbot among different CMFD levels, but there were significant differences in protein digestibility and protein efficiency ratio(PER) of Turbot among different CMFD levels. The protein digestibility and PER of Turbot were significant higher than the control when the CMFA at the rang of 0.5%～2.0%. At the 1.5% level, the protein digestibility and PER of Turbot were lower than other levels, this is possible the result of different size of the Turbot.3. There were no significant differences in the activity of the lipase in foregut in Turbot among different CMFD levels, but the activities of the pepsin in stomach is significant increase with the increase of CMFD level at the rang of 0～1.0%.The activities of the pepsin in stomach deceased when the level of CMFD exceed 1.0%, the reason of this was unknown.4. There were significant differences in the spleen index in Turbot among different CMFD levels and the spleen index was the highest at the level of 1.0%. 5. The phagocytic percentage of the hemocytes was significant increased with the add of CMFA, but there were no significant differences in the phagocytic percentage of the hemocytes from level 0.5% to level 2.0%. The phagocytic index of the hemocytes increased with the increase of the level of CMFA at the rang from 0.5% to 2.0%, but there were no significant differences between the level of 1.5% and the level of 2.0%. If the phagocytic index of the hemocytes will continue increase with the continue increase of level of CMFA was unknown.6. The serum lysozyme activities of Turbot was significant increased when the CMFA level from 1.0% to 2.0%, and the serum lysozyme activities was highest at the level of 1.0%.7. The serum SOD activities of the Turbot was significant higher than other levels when CMFA at the levels of 1.5% and 2.0%,and there were no significant differences between the level of 1.5% and the level of 2.0%. If the serum SOD activities will continue increase with the continue increase of level of CMFA was unknown too.In sum, CMFA would improve the activity of digestive enzymes, the digestibility to nutrition and Non-Specific immunity in Turbot at specific levels. Thus CMFA decreased feed coefficient and improve growth of Turbot. We considered that the fitting level of CMFD for Turbot diets is 1.0%.