微藻在海水鱼类苗种培育过程中的作用

The functions of microalgae in marine fish larviculture

主要从营养、促摄食以及益生作用三方面来综述微藻在海水鱼类苗种培养过程中的作用。在海水鱼类苗种培育过程中,微藻(microalgae)已得到广泛应用。由于绿藻的应用常使养殖水体呈现绿色,被形象地称为绿水养殖(green water culture)模式。微藻的作用首先是作为营养源直接供给仔鱼营养,或通过轮虫(Brachionus plicatilis)等生物饵料的富集或载体作用间接为仔鱼传递营养物质;微藻还可以通过提供微量营养元素在仔鱼摄食行为的建立、调节以及消化生理的刺激等方面发挥作用。除营养作用外,添加微藻还具有改善水质、增加水体混浊度和光对比度的作用,从而提高食饵的背景反差,增加海水仔鱼的摄食率。此外,微藻也可以调节养殖水体以及仔鱼肠道的微生态系统,维持水体及仔鱼肠道的菌群平衡,通过发挥益生作用减少病原菌的暴发。

Microalgae has been widely used in marine fish larvicluture for many years. Generally,the cultural water is green color for the predominant usage of chlorophytes,as a result,the technique is called green water culture. Microalgae is believed to improve the nutritional conditions of the fish larval,either directly by active feeding or indirectly through improving the trophic value of live feed,such as rotifers and Artemia spp. Besides its nutritional value,microalgae seem to be beneficial in the feeding behavior and modulating the digestive physiology of fish larvae through： 1. increase of turbidity,light scattering and attenuation,and visual contrast enhancement; 2. chemical and digestive stimulants resulting in more digestive enzymes and activity. More recently,with the emergence of the concept of ＂probiotics＂,microalgae acted as ＂probiotics-alga＂ during the finfish larval culture： including its antibacterial properties,and a modulating function in the bacterial flora balance of culture water as well as the skin and gut of the larval fish and live feed.