SHORT-TERM EFFECTS OF FUCOIDAN SUPPLEMENTATION ON ARGININE ABSORPTION AND BLOOD CHEMISTRY PROFILE OF RED SEA BREAM Pagrus major

This study aimed to evaluate the effects of fucoidan as a dietary supplement administered orally to red sea bream Pagrus major for 5 days. Two diets were formulated without (Diet 1) or with fucoidan (Diet 2). Each diet was fed to five groups of 15 fish each with a mean weight and length of 36.42g±2.05 g and 11.36±0.26 cm, respectively. Hematocrit and arginine profiles were assessed at the start of the feeding experiment. Results revealed that hematocrit levels in both fish fed Diet 1 and  2 were within the normal range at 1, 3, 6, 12 and 24 hours after feeding (haf). On the other hand, arginine absorption of Diet 2 peaked at 1 haf, then declined for the successive sampling period.  The small number of samples might be the reason for the erratic trend of fish fed Diet 1. At the end of feeding trial, a stress test (hypoxiation) was conducted for 5 minutes followed by a 1 hour recovery time. Collection of blood samples was done before and after the test. Interestingly, fucoidan supplementation improved the blood characteristics of fish. Blood hematological response of Diet 2-fed group was not altered after stress exposure. Total serum protein of Diet 1 was enhanced and was higher compared to Diet 2-fed. Meanwhile, an increase in triglycerides, glucose and cholesterol levels were observed in both diets. Other blood parameters (blood urea nitrogen, bilirubin and glutamic pyruvate transaminase) was not affected. This shows that fucoidan is a good source of arginine which is important in synthesizing proteins and improve immune functions. As a supplemental diet, it could positively affect fish health condition and help protect red sea bream against a physiological stressor even when given for a short period of time.