滇池食蚊鱼胚胎发育特点及与母体的营养联系  

The embryonic weight gain process and its connection with maternal nutrition of the ovoviviparous mosquitofish Gambusia affinis

作　　者：任司琪 陈国柱[1,2,3] REN Siqi;CHEN Guozhu(Yunnan Key Laboratory of Plateau Wetland Conservation,Restoration and Ecological Services,Southwost Forestry University,Kunming 650224,China;National Wetland Ecosystem Fixed Research Station of Dianchi,Southwest Forestry University,Kunming 650224,China;National Plateau Wetland Research Center,College of Wetlands,Southwest Forestry University,Kunming 650224,China)

机构地区：[1]西南林业大学云南省高原湿地保护修复与生态服务重点实验室,云南昆明650224 [2]西南林业大学云南省滇池湿地生态系统国家定位观测研究站,云南昆明650224 [3]西南林业大学国家高原湿地研究中心/湿地学院,云南昆明650224

出　　处：《中国水产科学》2023年第7期831-840,共10页Journal of Fishery Sciences of China

基　　金：国家自然科学基金地区基金项目(32060315);云南省高原湿地保护修复与生态服务重点实验室开放基金项目(202105AG070002)。

摘　　要：卵胎生是鱼类为适应特定环境进化出的一种生殖策略。食蚊鱼(Gambusia affinis)是典型的卵胎生鱼类,厘清其卵胎生特征是否在入侵云贵高原过程中发生适应性演化的问题,有助于深入了解其种群快速扩散机制。本研究用常规解剖观察法、称重法,针对滇池种群胚胎发育特点、干湿重变化及与母体营养联系问题开展研究。结果显示,滇池食蚊鱼胚胎发育过程依赖于卵黄营养供给,在产出前,卵黄仅微量残余,身体发育完善,基本保持了物种固有的卵胎生特点。胚胎湿重在胚胎发育过程中显著增加,但同时干重损失也十分明显(30.4%),营养指数(MI)为0.70,提示母体对胚胎没有受精后的特定营养供给,支持食蚊鱼是严格意义上的卵磷脂营养型(卵胎生)鱼类观点。其胚胎(仔鱼)出现小型化趋势,胚胎湿重、干重及初生体长等关键生态适应性性状明显低于已研究的其他低地种群,表现出对高原环境的适应性响应。这种响应是否有助于其向更高海拔的高原环境扩散值得进一步深入研究。Ovoviviparity is a reproductive strategy evolved by fish to adapt to specific environment.Gambusia affinis is a typical ovoviviparity fish.Clarifying whether its ovoviviparity characteristics have adaptive evolution in the process of invasion into the Yunnan-Guizhou Plateau will help us to understand the mechanism of its rapid population spread.Therefore,we conducted the research on the characteristics of embryonic development,changes in dry and wet weight,and the relationship with maternal nutrition in G.affinis Dianchi Lake population using conventional anatomical observation and weighing methods.The results showed that the embryonic development process of Dianchi Lake population depended on the supply of yolk nutrition.Before production,the yolk was basically consumed,and the body developed well,basically maintaining the inherent ovoviviparity characteristics of the species.The wet weight of embryos increased significantly during embryonic development,but at the same time,the dry weight loss was also very obvious(30.4%),and the nutrition index(matrotrophy index,MI)was 0.70,which suggested that the mother had no specific nutrition supply for embryos after fertilization,supporting the view that the G.affinis was a strictly lecithin trophic(ovoviviparity)fish.The embryo(fry)shows a trend of miniaturization,and key ecological adaptive traits such as wet weight,dry weight,and initial body length of the embryo are significantly lower than other lowland populations that have been studied,demonstrating an adaptive response to plateau environments.Whether this response contributes to its diffusion in higher altitude plateau environments deserves further in-depth research.

关 键 词：食蚊鱼 卵胎生 胚胎 发育 营养联系 

分 类 号：S917[农业科学—水产科学]