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Respectively in 2005, 2006 and the March Select abdominal swelling, soft drooping, well-developed female, Yuta door taimen (Hucho taimen) artificial spawning broodstock, insemination. And by artificially fertilized eggs and nurturing obtained larvae, juveniles, juvenile, adult fish, and collect samples, applied anatomy, histology, histochemistry method taimen fish digestive system into the structure, occurrence and digestive system development, as well as development of starvation on juvenile fish were studied, and the results are as follows: 1. adult fish digestive system by the oropharyngeal cavity, esophagus, stomach, intestine and pyloric caeca components. Oropharyngeal cavity distribution jaw teeth, palate teeth, plow teeth, pharyngeal teeth and tongue teeth, mucous layer has a lot of mucus cells and a small number of taste buds; esophagus thick and short, muscular layer developed; stomach was \is obvious cardia, fundus and pylorus, from the inside out sequentially from the mucosa, submucosa, muscular layer and serosal layer, the lower part of the gastric mucous layer; intestine and pyloric caeca organizational structure is basically the same, by the mucosal layer, submucosa, muscular layer and serosal layer, distributed in the mucosal layer of mucus cells and used in a large number of protein digestion eosinophilic cystic structure. And pancreas were handled separately liver larger. (2) accumulated up to 7.83 ℃ · d when the zygote cleavage stage finish; accumulated temperature of 40.04 ℃ · d blastocyst stage finish; hatching reached 82.39 ℃ · d when, after gastrulation and neurula stage embryo begins empty closed; accumulated up to 262.69 ℃ · d begin rupture and become newly hatched larvae. 14d fertilization appears below the notochord solid cell mass, as the digestive tract primordia. Further development of the digestive tract fertilization 26d form a distinct layers, the muscle layer differentiation is obvious, and the inner wall of the digestive tract in a large number of dual-core nuclear mitotic enclaves and absorptive cells; fertilization addition 28d junction oropharyngeal cavity and esophagus, anus , has been through the entire pipeline, into a liver volume increases. Newly hatched larvae mouth with the outside world, rupture of 10d intraoral mandible, maxilla are already calcified, oral freely closure, esophagus front began to appear cavity, stomach epithelium mitosis further strengthened appear 5 to 7 mucosal bi, liver apparent in the central vein and hepatic cell cord. After the rupture of esophageal mucosa appeared 20d mucous cells in the stomach and intestines at the junction of enlargement parts appear constricted, liver hepatocytes middle vacuolation begin more serious. 66d stomach rupture is basically the same structure and adult fish is divided into distinct cardia, pylorus and fundus. Intestinal structure and adult fish is basically the same, the foregut and rectal organizational structure similar to the mucosa, submucosa, muscular layer and serous layer. 3 hungry juvenile black body, large head body lean, body height lower than the control, full-length shorter than the control, stomach, intestines particularly strong at the melanin; chronic hunger in the brain after subsidence. Prolonged starvation resulted in substantial cannibalization phenomenon; juveniles PNR to rupture after 39d. Hunger juvenile fish digestive system development slowed down, hunger 15d stomach muscle growth reaches a maximum thickness 51.50μm, after continuously reduce hunger 33d reached the lowest value 42.22μm. Gastric severe structural damage, the performance of glandular cells atrophy, gastric reduction in the number and arrangement of messy, stomach muscle fibers loose reticular, stomach mucous layer of hunger 21d reached the maximum 34.16μm, later as starvation time, mucosal epithelial cells height decreased, hunger 33d mucous layer thickness reaches the minimum value 18.38μm. Hunger 21d of intestinal mucosa layer and muscle layer fully developed, developed to the maximum thickness, respectively 31.71μm and 21.96μm, later experiments conducted with eosinophilic granular cytoplasm decreased, and osteoporosis, intestinal epithelial cell height also declined, duodenal microvilli faults and a lot of mucus cell rupture; when hunger 33d when the mucous layer and muscle layer height decreased to the lowest values ??were 20.00μm and 24.42μm. Hunger 27 d, the blurring boundaries between the liver cells, nucleolus atrophy or disintegration of bias or attached to the nuclear membrane, resulting in some nuclear membrane thickening, and make vacuoles.
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