Albokhadaim Ibrahim, Hammond Chrissy L, Ashton Clare, Simbi Bigboy H, Bayol Stephanie, Farrington Samantha, Stickland Neil
The Royal Veterinary College, Royal College Street, London, NW1 0TU, UK.
J Exp Biol. 2007 May;210(Pt 10):1735-41. doi: 10.1242/jeb.003194.
Larval muscle development in Atlantic salmon is known to be affected by temperature; however, the long term effects and possible mechanisms involved are less well understood. Therefore, the aim of this study was to evaluate the influence of egg incubation temperature on post-hatch muscle growth and fish activity. Salmon eggs were incubated at either 10 degrees C or 5 degrees C from fertilization until hatching, then subsequently both groups were reared at 5 degrees C. Fish from both groups were sampled at the eyed stage, 6 and 21 weeks after first feeding, for muscle cellularity analysis and immunocytochemistry. In addition, to try to establish a mechanism for altered growth, the activity of the fish was measured at 3, 6 and 21 weeks after first feeding. Our results demonstrate that whereas fish incubated at 10 degrees C grow faster, the fish incubated at 5 degrees C show a more sustained period of muscle growth and by 21 weeks are significantly longer, heavier and have more muscle fibres than those fish incubated at a higher temperature. We also demonstrate that fish raised at 5 degrees C show increased food seeking activity throughout development and that this may explain their sustained growth and muscle development. These results taken together, demonstrate that egg incubation temperature up to hatching in salmon is critical for longer term muscle growth, twinned with increased activity. This is of interest to the aquaculture industry in term of the production of good quality fish protein.
已知大西洋鲑鱼幼体的肌肉发育会受到温度影响；然而，其长期影响及潜在机制却鲜为人知。因此，本研究旨在评估鱼卵孵化温度对孵化后肌肉生长及鱼类活动的影响。鲑鱼卵从受精到孵化期间分别在10摄氏度或5摄氏度下进行孵化，之后两组均在5摄氏度下饲养。在眼点期、初次摄食后6周和21周时，对两组鱼进行采样，用于肌肉细胞分析和免疫细胞化学研究。此外，为了探寻生长改变的机制，在初次摄食后3周、6周和21周时测量了鱼类的活动。我们的研究结果表明，虽然在10摄氏度下孵化的鱼生长更快，但在5摄氏度下孵化的鱼肌肉生长持续时间更长，到21周时，它们比在较高温度下孵化的鱼明显更长、更重，且肌肉纤维更多。我们还证明，在5摄氏度下饲养的鱼在整个发育过程中觅食活动增加，这可能解释了它们持续的生长和肌肉发育。综合这些结果表明，鲑鱼孵化前的鱼卵孵化温度对长期肌肉生长至关重要，同时伴随着活动增加。就优质鱼类蛋白质的生产而言，这对水产养殖业具有重要意义。
