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鱼类和所有动物一样,维持生命的能源和建造自身的原料,均取自食物。在鱼类幼小时期,其消化器官尚未特化,一般是吞食水中细微动植物;当鱼体长大,则形成各种各样的食性。鱼类的食性,是长期以来,“种”的形成过程中,对环境的适应而产生的一种特性。不同的食性,与其生活习性、消化系统的构造密切相关。按照摄取食物的性质不同,可以将鱼类食性划分为四个营养类型: 一、草食性:摄取植物性食物。即以高等水生维管束植物(水草)或低等的藻类为食的鱼类。如草鱼、长春鳊等鱼类,除摄食水草外,还喜食许多陆生旱草及瓜、菜叶片
Fish, like all animals, sustains life’s energy and builds its own ingredients, all from food. In the early stages of fish, its digestive organs have not been specialized, usually swallowing water plants and plants; when the fish grow up, the formation of a variety of food habits. The feeding habits of fish has long been a characteristic of adaptation to the environment during the formation of “species”. Different diet, with its habits, the structure of the digestive system is closely related. According to the different nature of food intake, fish food can be divided into four types of nutrition: First, herbivory: intake of plant foods. Ie, fish fed on higher aquatic vascular plants (aquatic plants) or lower algae. Such as grass carp, catfish and other species of Changchun, in addition to feeding water plants, but also eat a lot of terrestrial dry grass and melons, leaves