Hou Zhenxin, Fuiman Lee A
Marine Science Institute, The University of Texas at Austin, 750 Channel View Drive, Port Aransas, TX 78373, United States of America.
Marine Science Institute, The University of Texas at Austin, 750 Channel View Drive, Port Aransas, TX 78373, United States of America.
Comp Biochem Physiol B Biochem Mol Biol. 2021 Oct-Dec;256:110639. doi: 10.1016/j.cbpb.2021.110639. Epub 2021 Jun 24.
Embryonic and early larval development and metabolism of most teleost fishes are fueled entirely by maternally derived nutritional resources (yolk and oil) before the onset of exogenous feeding. The composition of those resources depends, in part, on maternal diet. To examine how diet-induced variations in egg composition affect embryonic and larval utilization of endogenous lipids and fatty acids, we fed red drum (Sciaenops ocellatus) broodstock four different diets to produce distinctive fatty acid compositions in eggs but with no significant difference in total lipid content. We sampled embryos and unfed larvae every 12 h from 12 h post-fertilization (hpf) until starvation (96-120 hpf; n = 5 spawns per diet group). Rates of utilization of the oil globule were significantly different among diet groups, resulting in significant differences in mean oil globule size at the first feeding stage (84 hpf). Utilization rates for 15 fatty acids were significantly different among diet groups and were proportional to their initial concentration. As a result, differences in larval fatty acid compositions among maternal diet groups diminished over time but remained different even at later stages. In addition, larval standard length at 84 hpf was positively correlated with egg total lipid content. This study suggests that the fatty acid composition of yolk and oil affects energy metabolism and tissue composition in red drum larvae. These effects could have consequences for the survival and essential physiological functions of fish larvae during the critical period of transition to exogenous feeding.
大多数硬骨鱼类在开始外源摄食之前，其胚胎和幼体早期发育及新陈代谢完全由母体提供的营养资源（卵黄和油脂）来维持。这些资源的组成部分取决于母体饮食。为了研究饮食引起的卵组成变化如何影响胚胎和幼体对内源脂质和脂肪酸的利用，我们给红鼓鱼（眼斑拟石首鱼）亲鱼投喂四种不同的饲料，以使卵产生独特的脂肪酸组成，但总脂质含量无显著差异。从受精后12小时（hpf）开始，每隔12小时对胚胎和未摄食的幼体进行采样，直至饥饿（96 - 120 hpf；每个饲料组n = 5窝）。不同饲料组间油球的利用率存在显著差异，导致初次摄食阶段（8 hpf）的平均油球大小存在显著差异。15种脂肪酸的利用率在不同饲料组间存在显著差异，且与它们的初始浓度成正比。因此，母体饲料组间幼体脂肪酸组成的差异随时间逐渐减小，但即使在后期仍存在差异。此外，84 hpf时幼体的标准体长与卵总脂质含量呈正相关。本研究表明，卵黄和油脂的脂肪酸组成会影响红鼓鱼幼体的能量代谢和组织组成。这些影响可能会对鱼类幼体在向外源摄食过渡的关键时期的生存和基本生理功能产生影响。
