北极茴鱼胚胎及仔鱼发育

研究对人工繁殖的北极茴鱼(Thymallus arcticus grubei)胚胎发育开展系统观察,记录分析其胚胎及仔鱼发育各时期的形态特征,旨在为北极茴鱼的人工繁育和种质资源保护提供必要的基础数据。结果显示,北极茴鱼受精卵呈圆球形,金黄色,沉性卵,未吸水卵径(2.46±0.14) mm,吸水卵径(3.14±0.18) mm,卵黄质内有多个油球。油球的数量和空间分布在胚胎发育过程中发生了规律性变化。在孵化水温(11.06±0.72)℃,溶氧8.3—9.8 mg/L条件下,历时301h完成整个胚胎发育过程,所需积温为3384.84h·℃,经历合子期、卵裂期、囊胚期、原肠胚期、神经胚期、器官形成期和孵化出膜7个阶段,共26个时期。北极茴鱼仔鱼尾鳍、胸鳍的分化和眼色素沉积在受精卵胚胎发育后期就已经完成,背鳍、腹鳍、臀鳍和脂鳍等在胚后发育过程中相继分化。其初孵仔鱼平均全长为(9.33±0.35) mm,仔鱼卵黄囊呈圆球形, 18日龄时卵黄囊和油球被完全消耗。其早期发育阶段(0—16日龄)的生长特性符合公式:y=0.0005x⁴–0.0201x³+0....

EMBRYONIC AND LARVAL DEVELOPMENTAL CHARACTERISTICS OF THYMALLUS ARCTICUS GRUBEI

Thymallus arcticus grubei is only distributed in the Irtysh River basin in northern Xinjiang Uygur Autonomous Region in China. In recent years, due to overfishing and construction of water conservancy projects, its resources have declined sharply. It was listed as a second-level protected fish in Xinjiang Uygur Autonomous Region in 2004. This research carried out systematic observations on the embryonic development of artificially propagated Thymallus arcticus grubei, and recorded and analyzed the morphological characteristics of their embryos and larvae at various stages of development, aiming to provide necessary basic data for the breeding of Thymallus arcticus grubei and resource protection. The results showed that the fertilized eggs of Thymallus arcticus grubei were spherical, golden yellow, sinking eggs, unabsorbed eggs diameter (2.46±0.14) mm, water-absorbed eggs diameter (3.14±0.18) mm, and there were multiple oil droplets in the yolk. The number and spatial distribution of oil droplets changed regularly during embryonic development. Under the conditions of incubation water temperature (11.06±0.72)℃ and dissolved oxygen of 8.3—9.8 mg/L, it takes 301h to complete the entire embryonic development process, and the required accumulated temperature is 3384.84h·℃. There are 7 stages, zygote, cleavage, blastula, gastrula, neurula, organ formation and hatching, totaling 26 stages. The differentiation of caudal and pectoral fins and eye pigmentation of Thymallus arcticus grubei larvae have been completed in the late embryonic development of the fertilized egg, and the dorsal fin, pelvic fin, anal fin, adipose fin, etc. differentiated in the post-embryonic development process. The average length of the newly hatched larvae is (9.33±0.35) mm. The yolk sac and oil droplets are completely consumed at the age of 18 days. The growth characteristics of its early developmental stage (0—16 days old) conform to the formula: y=0.0005x4–0.0201x3+0.2264x2–0.3773x+9.6102 (R2=0.9968). This study preliminarily clarified the timing characteristics of the embryonic development and larval development of Thymallus arcticus grubei, and provided a theoretical basis for the future large-scale breeding of seedlings.