Abstract: This paper studied the effects of delaying first breeding Hucho taimen larvae for different days on the larvae growth, survival, and body size. Five treatments were installed, i.e., feeding begins on the first eating day (control, S₀) and on the 9th, 12th, 15th, and 18th days after the first eating day (S₁-S₄) at 10.4-14.9 ℃, respectively. By the end of the experiment (36-day), the growth rate and initial feeding rate in S₁ was higher than that in S₀, and the overall mortality rate in S₁ was lower, but the body size and mass in S₁ and S₀ had no significant difference. Compared with S₀, S₂ had higher growth rate, initial feeding rate, total mortality, and selfmutilation mortality, the body mass was significantly lower, but the body size had less difference. S₃ had higher first feeding rate, body size, total mortality, and selfmutilation mortality, but significantly lower body mass than S₀, whereas the growth rate had less difference. In S₄, the growth rate and body mass were lower, and the total mortality and selfmutilation mortality were higher than those in S₀. It was suggested that under the same conditions, delaying first feeding for 9 days would induce H. taimen larvae presenting “completely compensatory growth”, and this feeding way could be applied for the culture of H. taimen larvae in their initial feeding period.

Key words: Hucho taimen, delayed feeding, compensatory growth, feeding, size difference.