Jalali Sara, Jamili Shahla, Sayyad Bourani Mohammad, Ramezani-Fard Ehsan, Sepahdari Abolfazl
Department of Natural Resources and Environment, Science and Research Branch, Islamic Azad University, P.O.Box 14515/775, Tehran, Iran.
Iranian Fisheries Sciences Research Institute, Agricultural Research Education and Extension Organization (AREEO), P.O. Box: 15745-133, Tehran, Iran.
Anat Sci Int. 2019 Mar;94(2):192-198. doi: 10.1007/s12565-018-00472-0. Epub 2019 Jan 1.
In this study we examined the ontogenic development of the digestive tract of Vimba bream (Vimba vimba, Family: Cyprinidae) during the first 60 days of life (hatching to 60 days after hatching [DAH]). Samples of developing Vimba bream were randomly selected at various stages of development: 1-8, 10, 15, 20, 25, 30, 40, 50, and 60 DAH. For the histological and histochemical studies on the development of the alimentary canal, tissue sections prepared from the sampled hatchlings were stained with hematoxylin-eosin and periodic acid-Schiff and observed under a light microscope. The histological structures of both the mouth and esophagus were fully developed at 5 and 7 DAH, respectively. Intestinal differentiation was observed at 2 DAH, while mucosal folds appeared on the intestinal bulb at 7 DAH. At 5 DAH, with the appearance of goblet cells in the epithelium of the mouth, pharynx, and esophagus, the larvae showed secretion activity in these organs. At 6 DAH, secretion was observed in the intestine; at this stage of development, the surface of the gastrointestinal tract was covered in a neutral mucous-like layer of polysaccharide. The histological observations indicate that the early development of the digestive tract in Vimba vimba enables larvae to efficiently ingest and digest exogenous feed very quickly after hatching.
在本研究中，我们研究了赤睛鳟（Vimba vimba，鲤科）在出生后的前60天（孵化至孵化后60天[DAH]）消化道的个体发育情况。在发育的各个阶段随机选取发育中的赤睛鳟样本：1 - 8、10、15、20、25、30、40、50和60 DAH。为了对消化道发育进行组织学和组织化学研究，从所采集的幼体中制备的组织切片用苏木精 - 伊红和过碘酸 - 希夫染色，并在光学显微镜下观察。口和食管的组织结构分别在5 DAH和7 DAH时完全发育。在2 DAH时观察到肠道分化，而在7 DAH时肠球出现黏膜褶皱。在5 DAH时，随着口、咽和食管上皮中杯状细胞的出现，幼体在这些器官中表现出分泌活性。在6 DAH时，在肠道中观察到分泌现象；在这个发育阶段，胃肠道表面覆盖着一层中性的多糖黏液样层。组织学观察表明，赤睛鳟消化道的早期发育使幼体在孵化后能非常迅速地有效地摄取和消化外源饲料。
