三碘甲腺原氨酸对斜带石斑鱼卵黄囊期仔鱼消化道发育和存活的影响  

The effects of 3,5,3'-triiodo-L-thyronine on the alimentary development and survival of orange-spotted grouper yolk-sac larvae

作　　者：唐啸尘[1] 刘晓春[1] 林浩然[1] 

机构地区：[1]中山大学水生经济动物研究所

出　　处：《水产学报》2006年第6期727-732,共6页Journal of Fisheries of China

基　　金：国家海洋863项目(2003AA603011);广东省科技计划项目(2001A3050201);教育部科学技术研究重点项目(02150);广东省重大科技兴海项目(A200000A02)

摘　　要：运用放射免疫测定方法检测了斜带石斑鱼早期发育过程中三碘甲腺原氨酸(T3)的变化,并用T3处理卵黄囊期仔鱼,研究其对发育、生长和存活的影响。斜带石斑鱼受精卵中含有相当量的T3,T3随发育而逐渐下降,到仔鱼开口时已经检测不到,提示甲状腺激素可能被胚胎和卵黄囊仔鱼所利用而参与其发育进程。在孵化后24h内,T3促进发育的作用不明显;在孵化24h后,T3对仔鱼消化道的发育有促进作用。在孵化72h后,0.01mg.L-1T3处理组仔鱼直肠管径明显比对照大,而小肠管径和全长与对照相比差异均不明显;0.1mg.L-1和1mg.L-1T3处理组仔鱼小肠和直肠管径显著比对照大,而全长显著比对照短。1mg.L-1T3显著加速了仔鱼卵黄囊的吸收,但对油球的吸收无影响。在孵化后第8天,0.01mg.L-1T3处理组仔鱼存活率明显比对照组高。结果表明,甲状腺激素促进卵黄囊期仔鱼消化道发育的作用与发育时期密切相关,孵化后24h内,消化道对T3不敏感,此后则变得敏感;0.01mg.L-1T3能提高仔鱼存活率。The changes of 3,5,3 ＇-triiodo-L-thyronine （T3） levels during the early developmental stages of orange-spotted grouper （ Epinephelus coioides） were examined by radioimmonoassay, and the effects of T3 on grouper yolk-sac larvae were studied. The fertilized eggs contained a substantial amount of T3. The levels of T3 in eggs gradually decreased during embryonic and yolk-sac larval development, and T3 could not be found at first feeding. The decrease of T3 levels in fertilized eggs during development suggests that TH could be utilized to act on the embryonic development and the yolk-sac larval development of orange-spotted grouper. The effect of T3 on larval development was not obvious within 24 hours post-hatching（hph）, however, the advancement in development of gut was induced by T3 treatment after 24 hph. Compared to the control, the diameter of larval rectum in 0.01 mg·L^-1 T3 groups was significantly longer but the differences in both the diameter of intestine and the total length of larvae was not significant at 72 hph. Both the diameters of larval intestine and return the rectum in 0.1 mg·L^-1 and 1 mg·L^-1 T3 groups were obviously longer than those in the control, but the total length of larvae was obviously shorter than that in the control at 72 hph. The resorption of yolk sac was accelerated by 1 mg·L^-1 of T3 treatment, but that of oil globule was not. The rate of survival in 0.01 mg·L^-1 T3 groups was obviously higher than that in the control in 8 dph. The results indicated that the action of T3 on development of gut was closely related to developmental stages. The development of larval gut was susceptible to T3 treatment after 24 hph but that was not within 24 hph. The rate of larval survival could be promoted by lower concentration of 0.01 mg·L^-1 T3 treatment.

关 键 词：斜带石斑鱼 卵黄囊仔鱼 消化道发育 三碘甲腺原氨酸 

分 类 号：S917[农业科学—水产科学]