【作者】 王春芳；

【导师】 谢从新；

【作者基本信息】 华中农业大学 ， 水产养殖， 2001， 硕士

【摘要】 本文研究了黄颡鱼早期发育阶段摄食和消化器官的发育特征、食物组成及其选食性。结果如下： 1．黄颡鱼口器的大小、消化道的形状和肠道的长度均随鱼体的发育而变化。且鱼口宽和口高对所摄取的食饵对象的个体大小有明显的限制性。 2．3d龄时，颌弓、舌弓除基舌软骨外的各骨片、1～5对鳃弓和膜质鳃盖出现，奠定了开口摄食的形态学基础。13d龄咽颅部分骨片开始骨化，36d龄，所有骨片均已骨化。 3．随鱼体发育，消化道各部位粘膜层厚度与肌层厚度不断增加。而食道皱褶数比较稳定，皱褶高低不一。胃皱褶数和皱褶高变化无明显规律，肠皱褶数和皱褶高呈上升趋势。胃上皮细胞顶端无微绒毛。肠上皮细胞顶端微绒毛的厚度缓慢增加。杯状细胞数增加较快，尤以胃和肠显著。 4．黄颡鱼混合营养期的长短与温度有关。平均水温24℃～26℃时，约4d(3d～6d龄)；平均水温27℃～28℃时，仅2d(3d～4d龄)。仔鱼3d龄开口，主要以轮虫为开口饵料，在食物中枝角类占绝对优势时，以小型枝角类为其开口饵料。所摄食的饵料生物随着发育的进展而变化：摄食初期主要为轮虫，仔鱼后期主要为枝角类、桡足类，稚鱼期开始摄食水蚯蚓，幼鱼期则主要以水蚯蚓为食。这种变化主要由鱼类摄食和消化器官的发育完善，对饵料生物的喜好及饵料生物的易得性决定。 5．黄颡鱼仔稚鱼摄食具有明显的昼夜节律性。胃平均饱满指数在仔鱼前期、仔鱼后期和稚鱼期分别于21∶00、3∶00、6∶00达最高峰，均于15∶00达最低值。不同发育阶段的日摄食率分别为：仔鱼前期69.96％，仔鱼后期28.84％，稚鱼期10.00％。 6．饥饿影响黄颡鱼的形态、行为、体色及消化道组织结构的变化，尤以对前肠组织的影响最明显。在饥饿状态下及个体差异太大的情况下，会出现同类相残现象。更多还原

【Abstract】 The development of feeding organs and digestive tract as well as food selection in different stages are studied. The results are as following:1. The size of mouth, morphogenesis of the digestive tract and gut length increase with the growth of this species. The width and height of fish mouth apparently affect the size of food which is intaken.2. On the third day after hatching, the appearance of mandibular arch, hyoid arch(not including basihyoidian cartilage), the first to the fifth branchial arch and branchial stegite prepares for the first feeding in morphogenesis. In 13-day-old fry, the bony development of the pharyngeal skeleton has begun. In 36-day-old young fish, the whole bony development has already finished.3. In the group of feeding larvae, mucosa thickness and muscle thickness of different parts of digestive tract increase with the development of fish. Apart from comparative stability in the number of folds, the height of folds in esophagus, the number and the height of folds in stomach show no apparent law. However, in intestine, they both increase although they have something to do with fullness In stomach, we see no microvilli on the top of the single epithelium while in intestine, the epithelium cell is covered with microvilli, which grows slowly. Goblet cell increases rapidly, especially in stomach and intestine.4. The period of mix nutrition has relationship with temperature. When mean water temperature is between 24 and 26 , the period lasts for about four days(3days old to 6days old); when temperature is between 27 to 28 ,the period lasts for only two days(3days old to 4days old). The first feeding appears on the third day after hatching. The first food of larvae is Rotifera, But if Cladocera predominates in water, the first food can also be small Cladocera . The selection of main food varies with the development of food intake and digestive organs, changing as following sequence: Rotifera in early stage of feeding, then Cladocera first and Copepoda second in postlarval stage, Oligochaeta first intaken in juvenile stage, and then mainly Oligochaeta in young stage.5. Apparent day and night feeding rhythm is observed in larval and juvenile stages. The peak index of fullness lies at 21:00 in prelarval stage, 3:00 in postlarval stage and 6:00 in juvenile stage. The daily feed intake rate varies with the development. In those three stages, the daily feed intake rates are 69.96%, 28.84% and 10.00% respectively.6. Starvation has a great effect on morphology, behaviour, color and histology, especially the histology of intestine. The phenomenon of preying on internal species occurs when size hierarchy or lack of sufficient food exists.更多还原