Short Term Ration Restriction and Re-alimentation: Effect on Compensatory Growth, Body Composition and Insulin-like Growth Factor Gene Expression in Cyprinus carpio

摘要

Advanced fry of Cyprinus carpio (mean weight 1.73±0.02g) were fed at 10%, 25%, 50% and 75% of satiation as different treatment groups and one control group (6 weeks) for first phase (restriction feeding) and a second phase (8 weeks) of satiation feeding for all the treatments. At the end of first phase, there was significant difference in mean weight among the treatment groups (P0.05) but, after second phase (8 weeks), treatment group fed at 75% of satiation obtained significantly higher body weight than control, while 50% satiation fed group obtained similar weight as of control. FCR was found to be better at moderately restricted fed group (50% and 75% satiation). Crude protein and crude lipid content decreased in severely restricted groups (10% and 25% of satiation fed), compared to others after 14 weeks. IGF-I and IGF-2a gene expression in the liver was observed as down regulated during ration restriction and up regulated after re alimentation. However, after re-alimentation for 8 weeks, IGF-2a gene expression was recorded to be increasing and was higher than control. The study concludes that moderate levels of ration restriction (50% to 75% of satiation levels) is sufficient for effective growth and feed utilization.