. larvae might live on small or dissolved organic materials Otake et al., 1993 . In Japan, larvae that survived to 27 days were given artificial feed made from ground shark egg Ž. Tanaka, 1998 . Larvae that survived more than 250 days were given ground shark egg mixed with other nutritious materials under a light–dark controlled environment with Ž. intensive bottom-cleaning Tanaka, 1999a,b . This has been a revolutionary breakthrough in the larviculture of eel, but the larvae that survived were generally small in size, the 253-day-old larvae having the largest total length of only 30 mm. In Taiwan, larvae that survived 31 days were reared in water from a grow-out pond in which certain Ž. unknown factors might be present and beneficial for larval survival Yu and Tsai, 1994 . The difference in the morphology, particularly in the shape of the head and teeth, between hatchery-reared 31-day-old larvae and wild-caught larvae remains a mystery Ž. Liao, 1998; Liao et al., 1999 . The high mortality in larval rearing may be attributed to nutritional deficiencies andror unsuitable environmental conditions. The important characteristics of the representative finfish discussed in this paper are summarized in Table 5.
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