Effects of age, body size and season on food consumption and digestion of captive dugongs ( Dugong dugon ).

Food consumption and digestion of male and female dugongs ( Dugong dugon ) was examined by analyzing long-term (1979-1998) feeding records at Toba Aquarium (Japan). Throughout all captive feeding periods, dugongs consumed eelgrass ( Zostera marina ) and showed steady increases in feed consumption with a consistent weight gain of 42-45 kg a year. The daily consumption of male and female dugongs increased from 10-15 kg to 23-26 kg of fresh eelgrass, accounting for approximately 14 and 7% of their body weight at one and seven years old, respectively. Both dugongs had a marginal dry matter digestibility of over 90%. Food consumption varied between seasons and individuals. There were major reductions ( P <0.05) in consumption by the male in November and January and by the female in August and September. The seasonal reductions in food consumption coincided with high digestibility of eelgrass. [ABSTRACT FROM AUTHOR]