Effect of dietary protein, lipid and carbohydrate contents on the viscera composition and organ Indices of Cyprinus carpio communis fingerlings
This study aimed to determine a feed formulation with the best protein to energy ratio that would result in a better viscera composition and organ indices (OI) of Cyprinus carpio communis. Fingerlings having average weight of 1.64 ± 0.13 g and length of 5.26 ± 0.10 cm were fed on four different formulated feeds and a control feed (each in a triplicate set), 6% of their body weight, three times a day, during 90 days. Feeds were formulated using ground nut oil cake, mustard oil cake, rice bran, wheat bran, fish meal and soybean meal in order to suffice the balanced need of protein and energy of the common carp. Viscera composition and OI of fingerlings were measured. Results indicate that there was a significant increase in viscera lipid content with the increase in dietary carbohydrate level. The viscera lipid content was found highest in the fingerling fed on feed C and the least in the fingerlings fed on feed B. The eviscero-somatic index (EVSI) decreased significantly (P<0.05) with the increase in the dietary carbohydrate level, whereas the viscero-somatic and hepato-somatic indexes (HSI) increased significantly (P<0.05) with the increase in dietary carbohydrate level. The EVSI was the highest, whereas viscero-somatic index (VSI) and HSI were least in the fingerlings fed on the feed B. Moreover, the EVSI was the least, whereas viscero-somatic and HSI were highest in the fingerlings fed on feed C. This work concludes that feed B containing 40% protein, 9.31% lipid, 10.08% carbohydrate and having protein to energy ratio of 20.54 mg protein/kJ was the best feed for a more profitable and successful culture of the common carp.
Keywords: Protein to energy ratio, carp production, viscera composition, organ indices