不同温度对脊尾白虾胚胎发育与幼体变态存活的影响

Abstract

The shrimp,Exopalaemon carinicauda,commonly known as the ridgetail white prawn,is an important local fishery resource that has been targeted for aquaculture throughout China.This species makes up one third of the gross output of polyculture ponds in China;however,the artificial rearing of E.carinicauda needs to be improved.Water temperature plays an important role in the timing of embryo and larval development.Thus,the purpose of the present study was to determine the effects of temperature on the egg incubation period,survival and development period of E.carinicauda larvae reared in the laboratory.The number of days from spawning to hatching and mean rearing temperature were determined from 25 females.The egg incubation period decreased exponentially from 41 to 10 days with increasing mean temperatures of 15.3 to 28.1℃,but at 30℃,embryonic development could not be completed.The relationship between mean temperature(T) and egg incubation period was analyzed using the equation T=KV+C,based on heat summation theory.The lower critical temperature for embryonic development represented by parameter C was 12.18℃,and the sum of effective temperature for embryonic development was 3828.27℃·h.The larvae from each female were reared in 1.5 L beakers at six temperatures(18,20,22,24,26 and 28℃) and fed Artemia sp.nauplii.The number of days from hatching to the attainment of each larval stage decreased with increasing temperature,the period over which 90% of larvae from the T18—T28 groups developed into juvenile shrimps was 21,18,15,14,11 and 11 days,respectively.The survival rates of larvae decreased with development time.In particular,the survival rate of the T28 group decreased sharply over time.The survival rates,however,from incubation to juvenile shrimp showed no significant differences(P0.05) between the six groups.The individual dry weight of post-larva from the T18 group was the highest of all of the six groups(P0.05),and the individual dry weight of post-larva from the T28 group was the lowest,but there was no significant difference(P0.05) between the five groups from the T20 group to the T28 group.To conclude,water temperatures between 12.18℃ and 28℃ were most suitable for embryonic development,and temperatures from 22℃ to 26℃ were most suitable for rearing E.carinicauda larvae.