1- Department of Fisheries, Science and Research Branch, Islamic Azad University, P.O. Box 14515-775,Tehran, Iran. 2- Department of Fisheries, Science and Research Branch, Islamic Azad University, P.O. Box 14515-775,Tehran, Iran. , rajabi.h@srbiau.ac.ir 3- Department of Aquatic Animal Health, Faculty of Veterinary Medicine, University of Tehran, Tehran, Iran.
Abstract: (5366 Views)
This study evaluated the effects of diets containing 0, 2.5, 5, 7.5 and 10% Arthrospira platensis on skin pigmentation, growth performance, and digestive enzymes of koi, Cyprinus carpio. A completely randomized design was performed with five treatments and three replicates. One hundred and fifty koi fish with average initial weight of 30±1g were assigned to fifteen experimental tanks. The experiment lasted for eight weeks. Koi fish fed with 2.5% A. platensis (1.17±0.02) showed a significant lower growth performance than those fed with 7.5 and 10% A. platensis (1.39±0.02 and 1.46) (p<0.05). However, carotenoid (astaxanthin) concentrations of skin significantly increased with increased levels of dietary algae (p<0.05). The highest values of a* (red zones) and b* (yellow zones) were observed in fish skin fed with 10% A. platensis (4.33±0.15, 5.23±0.15, 5.23±0.15, 5.7±0.36, and 6.33±0.32, respectively). The activities of protease, amylase and lipase in dietary supplementation of 10%A. platensis were significantly higher than those of the control group (protease from 5.17±0.76 to 11 , amylase from 22±1.73 to 32.67±1.53 and lipase from 16.33±2.08 to 74.33±1.53. Liver enzymes also decreased significantly by increased dietary supplementation. (ALT: from 192.33±5.5 to 80.67±1.52, AST: from 1741.7±18.92 to 712.33±10.5, ALP: from 452.33±8.14 to 48±1, LDH: from 7287.3±34.64 to 7119.7±17.89). These results revealed that inclusion of 5-10% A. platensis in diets has a significant positive effect on growth rate, pigmentation, and improvement of digestive and liver enzymes activities in koi fish.
Ansarifard F, Rajabi Islami H, Shamsaie Mehrjan M, Soltani M. Effects of Arthrospira platensis on growth, skin color and digestive enzymes of Koi, Cyprinus carpio. IJFS 2018; 17 (2) :381-393 URL: http://jifro.ir/article-1-3357-en.html