干露胁迫对刺参中韩群体杂交子一代应激及免疫指标的影响

Comparative Study on Air Exposure Stress Responses of Hybrids Between Chinese and Korean Stocks of Sea Cucumber

通过刺参中国群体(C)和韩国群体(K)群体间杂交和群体内自繁,获得了4个交配组合CC(C♀×C♂)、KK(K♀×K♂)、CK(C♀×K♂)和KC(K♀×C♂)的子一代。实验研究了干露胁迫对4组刺参体腔液中儿茶酚胺类激素水平和免疫指标的影响,比较了刺参中韩群体杂交和自交子一代对干露胁迫的应激反应。结果显示:受到干露胁迫的4组刺参体腔液内儿茶酚胺类激素水平都出现上升的趋势,其中KK和KC组激素水平上升幅度大于CC和CK组。4组刺参体腔液内细胞数在胁迫开始后逐渐上升,KK和KC组在胁迫结束时显著高于初始值。4组刺参体腔液细胞吞噬活性都呈"降低-升高-又下降"的趋势,但在整个实验过程中变化不显著。干露导致4组刺参体腔液内超氧化物歧化酶活性显著上升,同时,KK和KC组的过氧化氢酶活性显著上升。4组刺参体腔液内溶菌酶活性在胁迫过程中受到抑制,但变化不显著。上述结果表明,刺参中韩群体杂交和自交子一代对干露胁迫的应激程度不同,CC和CK组子一代对干露胁迫具有更好的抗性。

Stress has been demonstrated to retard growth,depress immune,and compromise disease resistance in marine invertebrates.Therefore,in any aquaculture species,it will be beneficial to improve stress resistance through breeding.Heterosis resulting from cross between different populations is an important component of breed improvement in marine animals.Through complete diallel cross,the offspring of four mating combinations,C（♂）×C（♀）,K（♂）×K（♀）,C（♂）×K（♀）and K（♂）×C（♀）were obtained from mating within and between Chinese population（C）and Korean population（K）of sea cucumber（Apostichopus japonicus）.The objective of this study is to compare the physiological responses of four above-mentioned groups of the sea cucumber to air-exposure,one of the major handling stress during seed nursery of juvenile sea cucumber.The stress responses of four groups sea cucumber were evaluated following exposure to air for one hour.Coelomic fluid was sampled at 0（pre-challenge）,0.5,1,2,4,8,16 and 32h,for analysis of neuroendocrine and immune parameters.All groups represented classical neuroendocrine changes indicative of the generalized stress response.The concentrations of noradrenaline and dopamine in coelomic fluid increased during the stress,and the concentrations of noradrenaline at the end of stress were significantly higher than the initial values in four groups.The magnitudes of the catecholamines rised were greater in the K（♂）×K（♀）and K（♂）×C（♀）groups.Coelomocytes concentrations in coelomic fluid of four groups increased transiently after the beginning of the stress,and they were significant higher than the initial values in K（♂）×K（♀）and K（♂）×C（♀）groups at the end of stress.Although coelomocytes phagocytosis fluctuated during the experiment,there were no significant differences between different sample points.Air exposure increased the superoxide dismutase activities significantly in four groups and increased the catalase activities significantly in K（♂）×K（♀）and K（♂）×C（♀）groups.The lysozyme activities of four groups were depressed during stress,however they showed no significant differences during the experiment.The results indicated that the C（♂）×C（♀）and C（♂）×K（♀）groups were more resistant to the air exposure stress.