中国水产科学2025，Vol.32Issue(10)：1445-1456,12.DOI:10.12264/JFSC2025-0106
中国结鱼人工繁殖和早期发育研究
Artificial breeding and early development of Tor Sinensis
摘要
Abstract
Tor sinensis,a fish species endemic to the Lancang River system,is mainly distributed in its middle and lower reaches.This species is large in size,with palatable flesh and striking coloration,thereby integrating nutritional value with aesthetic appeal.However,the wild population of T.sinensis has substantially declined in recent years and is now listed as Near Threatened on the IUCN Red List due to hydropower development,environmental pollution,navigation,sand mining,overfishing,and invasive alien fish species.This species has important conservation significance and economic value.To supplement biological data on its early development and guide artificial breeding efforts,wild T.sinensis individuals were captured from the lower Lancang River system in 2022.After artificial acclimatization,experimental artificial breeding was conducted.From September to October each year,healthy males(with milky white semen released upon gentle abdominal pressure)and females(＞1.5 kg,with soft abdomens and swollen reddened genital pores)were selected at a 1∶1 ratio.First,females were injected with LHRH-A2 5 μg/kg,while males received no injection.After 18 h,females were injected with LHRH-A2 10 μg/kg+DOM 10 mg/kg+HCG 200 IU/kg,while males received 50％of the second dose of the females.Artificial dry insemination was performed 16 h post-injection.Embryos and fry were systematically monitored under a dissection microscope until reaching the juvenile stage.The results showed that 4 artificial breeding experiments were performed from 2022 to 2023,resulting in the induction of spawning in 14 females laying of 12 eggs,ultimately yielding an average induction rate of 87.5％.A total of 30000 mature eggs and 19000 hatched larvae were obtained.The fertilization and hatching rates reached up to 90.00％and 92.59％,respectively.The T.sinensis fertilized egg is characterized by its sedimentary,non-viscous,and light yellow properties,enabling it to be transported by water currents into the crevices between pebbles to avoid predator detection.The egg diameter measured(2.64±0.13)mm and increased to(3.50±0.18)mm following water absorption and swelling.The incubation period is extended;at water temperatures of 22-24℃,hatching occurs after 74-82 h,with an accumulated incubation temperature of 1725.45℃·h.The embryonic development process is categorized into 7 stages(i.e.,blastoderm,cleavage,blastula,gastrula,neural,organogenesis,and hatching stages)and 28 periods.The total length of the first hatched fish was(7.88±0.23)mm,38 pairs of muscle segments.From 0 to 5 days after hatching(DAH),larvae exhibited rapid growth during the endogenous nutrition stage.As time progressed,their overall growth rate gradually slowed down,with 4 DAH larvae demonstrating flat swimming behavior.Moreover,6 DAH larvae consumed exogenous nutrients.During the mixed nutrition period from 6 to 10 DAH,the growth rate continued to decelerate.At 24 DAH,the various organs of the larvae had fully developed,and their growth rate increased.At 31 DAH,the juvenile fish exhibited a total length of(18.14±0.65)mm.This study proposed a feeding strategy for T.sinensis.Feeding commenced at 6 DAH,with a high feeding frequency from 6-10 DAH.The feeding frequency could be continuously reduced from 10-24 DAH.At 24 DAH,normal feeding could be conducted once or twice daily.关键词
中国结鱼/人工繁殖/胚胎发育/仔鱼发育Key words
Tor sinensis/artificial breeding/embryonic development/larval fish development分类
农业科技引用本文复制引用
YANG Yang,DING Huiping,ZHONG Tian,WANG Yuesong,CHENG Rui,GAN Xing,ZHANG Zhiming..中国结鱼人工繁殖和早期发育研究[J].中国水产科学,2025,32(10):1445-1456,12.基金项目
中国华能集团科技项目(HY2021/S17-1). （HY2021/S17-1）
