Salimian Shekoofeh, Keyvanshokooh Saeed, Salati Amir Parviz, Pasha-Zanoosi Hossein, Babaheydari Samad Bahrami
Department of Fisheries, Faculty of Marine Natural Resources, Khorramshahr University of Marine Science and Technology, Khorramshahr, Khouzestan, Iran.
Department of Fisheries, Faculty of Marine Natural Resources, Khorramshahr University of Marine Science and Technology, Khorramshahr, Khouzestan, Iran.
Anim Reprod Sci. 2016 Feb;165:31-37. doi: 10.1016/j.anireprosci.2015.12.002. Epub 2015 Dec 12.
The aim of this study was to compare effects of triploidy induction on basal physiological and immunological characteristics in rainbow trout at three developmental stages including fertilized eggs, eyed eggs and fry. Eggs and milt were taken from eight females and six males. The gametes were pooled to minimize the individual differences. After insemination, the eggs were incubated at 10°C for 10min. Half of the fertilized eggs were then subjected to heat shock for 10min submerged in a 28°C water bath to induce triploidy. The remainder were incubated normally and used as diploid controls. Three batches of eggs were randomly selected from each group and were incubated at 10-11°C under the same environmental conditions in hatchery troughs until the fry stage. The first-feeding offspring were also reared under the same environmental and nutritional conditions for 38 days. Triplicate samples of 30 eggs (10 eggs per trough) from each group were selected 1.5h post-fertilization and at the eyed stage. Based on red blood cell analysis, nine diploid and nine triploid fish were also selected for study. The triploidy induction success rate was 87.1%. While diploid fish had greater body weights than those in the heat-shock treatment group, weight gain (WG%) was not different between the fry of the diploid and heat-shock treatment groups. Of thyroid hormones measured, 3,5,3'-triiodo-l-thyronine (T3) was less (P<0.05) in eyed eggs of the heat-shock treatment group, but thyroxine (T4) was greater in fry of the heat-shock treatment group as compared to those that were diploid. Cortisol concentration was greater in fry of the heat-shock treatment group as compared to those that were diploid suggesting that fry in the triploid state may be more susceptible to stressors. Concentrations of immune variables (lysozyme, ACH50, albumin, IgM, total protein, globulin and complement) were either comparable or greater in fry of the heat-shock treatment group suggesting that the immune system is not impaired in fish as a result of triploidy induction.
本研究的目的是比较三倍体诱导对虹鳟鱼在受精卵、眼点卵和鱼苗三个发育阶段的基础生理和免疫特性的影响。卵和精液分别取自8只雌鱼和6只雄鱼。将配子混合以尽量减少个体差异。授精后，将卵在10°C下孵育10分钟。然后将一半受精卵置于28°C水浴中热休克10分钟以诱导三倍体。其余受精卵正常孵育并用作二倍体对照。从每组中随机选取三批卵，在孵化槽中于10-11°C的相同环境条件下孵育至鱼苗阶段。初孵后代也在相同的环境和营养条件下饲养38天。在受精后1.5小时和眼点期，从每组中选取30枚卵（每槽10枚卵）的三份重复样本。基于红细胞分析，还选取了9条二倍体鱼和9条三倍体鱼进行研究。三倍体诱导成功率为87.1%。虽然二倍体鱼的体重比热休克处理组的鱼重，但二倍体鱼苗和热休克处理组鱼苗的体重增加率（WG%）并无差异。在所测定的甲状腺激素中，热休克处理组眼点卵中的3,5,3'-三碘-L-甲状腺原氨酸（T3）含量较低（P<0.05），但与二倍体鱼苗相比，热休克处理组鱼苗中的甲状腺素（T4）含量较高。与二倍体鱼苗相比，热休克处理组鱼苗中的皮质醇浓度较高，这表明三倍体状态的鱼苗可能更容易受到应激源的影响。热休克处理组鱼苗中免疫变量（溶菌酶、ACH50、白蛋白、IgM、总蛋白、球蛋白和补体）的浓度要么相当，要么更高，这表明三倍体诱导不会损害鱼类的免疫系统。
