The effects of ascorbate on the haematocrit and blood glucose level were evaluated in Nile tilapia alevins (Oreochromis niloticus) submitted to a transport simulation. Three experimental diets with different levels of vitamin C (16, 500 and 1000mg/kg) were given for 14 days before the simulation of the transport. The treatment containing 16mg of vitamin C showed the highest level of glucose after the simulation (108.5mg/dl immediately after the transport and 91mg/dl 12 hours after the transport). The vitamin C concentration of 1000mg/kg was the most efficient treatment to control glycemia increases (94.6mg/dl immediately after the simulation and 74.4mg/dl 12 hour after simulation). In the 500mg/kg treatment, the glucose level was 91.4mg/dl immediately after the simulation and 103.8mg/dl 12 hours after the simulation. The haematocrit values did not show any significative variation (P<0.05). The supplementation with 1000mg/kg of vitamin C for a 14 days period can be used in a prophylactic way to soften glycemia increases in Nile tilapia alevins submitted to transport stress.
fish; Oreochromis niloticus; glucose; vitamin C; haematocrit