230 B
. Tan, K. Mai J. Exp. Mar. Biol. Ecol. 256 2001 229 –239
1. Introduction
Vitamin K is essential for the synthesis of clotting factors in the livers of animals. Its metabolic role has been more clearly defined than that of the other three fat-soluble
vitamins in terrestrial animals even though it was the last of the fat-soluble vitamins to be discovered Suttie, 1980; Kormann and Weiser, 1983; Udagawa et al., 1993. The
classical role of vitamin K has been in the maintenance of normal hemostasis. Many types of compounds, such as phylloquinone PK , menaquinones VK and menadione
1 2
VK exhibit vitamin activity Udagawa et al., 1993. Phylloquinone vitamin K is
3 1
synthesised by plants and algae, whereas the menaquinone family MK vitamin K
2n 2
are products of bacterial biosynthesis. Water-soluble salts of the synthetic menadione are used in animal diets. Fish diets are commonly supplemented with menadione sodium
bisulfite MSB. Menadione and its salts are usually converted to MK-4 in animal tissues Nestor and Conrad, 1990; Udagawa et al., 1993; Grahl-Madsen and Lie, 1997.
In mammals, the requirement for vitamin K is met by a combination of dietary intake and microbiological synthesis in the intestine, but composition of diets and antibiotics
affect intestinal production Mathers et al., 1990. The effect of dietary vitamin K on physiological role and requirement has been
studied in several species of fishes and crustaceans. Vitamin K deficiency results in anemia and prolonged coagulation time in fish Halver, 1989; NRC, 1993. Menadione
is highly effective in preventing the molinate-induced anemia in common carp Kawatsu and Ikeda, 1988; Kawatsu et al., 1989. Menadione has been reported to be required for
larval kuruma shrimp, Penaeus japonicus Kanazawa, 1985, P
. monodon Shiau and Liu, 1994a and P
. chinensis Shiau and Liu, 1994b. However, the significance of intestinal production of vitamin K in fishes or crustaceans has not been established. In
21
salmonids, the vitamin K requirement for growth is suggested to be 10 mg kg dry diet
Halver, 1989. Increased blood clotting times, anaemia and hemorrhages in gills, eyes and vascular tissues have been reported in salmonids fed diets low in vitamin K or diets
supplemented with antibiotics Phillips et al., 1963; Kitamura et al., 1967; Halver, 1989. On the other hand, deficiency signs were not induced in channel catfish fed
antibiotics Murai and Andrews, 1977.
For mollusks, however, direct evidence is lacking in either the significance of intestinal production of vitamin K or dietary requirement for this vitamin. Haliotis discus
hannai is one of the most commercially important gastropods in aquaculture. At present, no information has been reported as to the essentiality or quantitative requirements of
vitamin K for this species. Therefore, the objective of this study was to investigate the effect of dietary vitamin K on survival, growth and tissue concentrations of
phylloquinone and or menaquinone-4 in the juvenile abalone, Haliotis discus hannai.
2. Materials and methods
