SHORT-TERM PERIODIC STARVATION OF LABEO ROHITA FINGERLINGS: EFFECT ON GROWTH AND HEALTH

An experiment was conducted to study the effect of periodic starvation on growth performance and health status of Labeo rohita fingerlings. L. rohita fingerlings (av. wt. 3.73 g) were periodically starved for 0, 1, 2 or 3 days per week (d/ wk) for a total duration of 10 weeks. On the day of feeding, fish were fed to satiation twice a day with a diet containing 30% crude protein and 6% lipid. Fish deprived of feed for 1 d/ wk consumed 7.05% less feed but had similar growth as the daily-fed fish during the experimental period. Whereas, those deprived of feed for 2 and 3 d/ wk had 18.6 and 28.6% lesser weight gain than the daily-fed fish, respectively. The body indices like condition factor (CF), hepatosomatic index (HSI) and gastro-somatic index (GSI) were not affected by periodic starvation, indicating that the health and nutritional status of the fish were not affected. The results of haematological responses, respiratory activity (also known as nitroblue tetrazolium or NBT assay) and lysozyme suggested that feed deprivation of 1 or 2 d/ wk did not compromise the immunity of the fish. Serum albumin level reduced in the periodically starved groups while conserving serum globulin. No change in histology of the liver and intestinal tissues was observed in periodically starved groups. It is concluded that feeding L. rohita fingerlings 6 days-a-week is cost effective in terms of saving feed without adversely affecting growth and health of the fish. Key words: Periodic starvation, growth, health, Labeo rohita, haematology, histology