【作者】 李茜；

【导师】 刘文斌； 王恬；

【作者基本信息】 南京农业大学 ， 动物营养与饲料科学， 2007， 硕士

【摘要】 本试验首先对异育银鲫的肠道组织形态及肠道G细胞的分布状况进行观察，并根据观察结果将其肠道进行划分；而后，进一步研究不同发育阶段异育银鲫肠道组织形态的变化特征；最后，探讨棉粕蛋白酶解物和豆粕蛋白酶解物对异育银鲫肠道生长发育的影响，旨在为今后鲤科鱼类的消化生理研究提供科学依据。本试验分为以下三个部分：1．异育银鲫肠道组织形态结构观察及功能分析研究本试验采用石蜡组织切片法和免疫组织化学法，对异育银鲫肠道组织的形态结构及胃泌素分泌细胞(G细胞)在肠道组织中的分布情况进行了研究，以探讨其肠道各部的功能。结果表明：异育银鲫的肠道横截面积、肌层厚度、粘膜皱襞个数、皱襞高度以及皱襞宽度的形态结构前后变化明显；沿肠道由前向后，肠道横截面积逐渐减小，粘膜皱襞个数逐渐降低，变化具有规律性；除肛门附近的肠道组织外，异育银鲫肠道各处均有G细胞分布，其分布密度由前至后逐渐降低，且G细胞分布密度的变化规律与上述5个形态指标的变化规律相一致。由此，可将异育银鲫肠道划分为前肠、中肠、后肠及直肠；其中各段长度分别为肠道全长的13.44％±2.19％、39.42％±0.70％、38.64％±1.94％和8.50％±1.02％。2．不同发育阶段异育银鲫肠道组织形态变化特征异育银鲫肠道的粘膜皱襞个数、粘膜皱襞宽度、肌层厚度和肠道横截面积这4个形态学指标，沿肠道由前至后的变化趋势，在3个发育阶段中均分别保持一致；其中，粘膜皱襞个数在3个发育阶段始终表现为先减少后增多的趋势；粘膜皱襞宽度在3个发育阶段均以前肠的值为最大，中肠与后肠之间差异始终不显著(P＞0.05)；肌层厚度和肠道横截面积在3个发育阶段，沿肠道由前至后，均始终表现为下降趋势。但粘膜皱襞高度由前至后的变化趋势，在3个发育阶段却发生较大变化；其中，幼鱼前期和成鱼期，肠道粘膜皱襞高度由前至后均呈现逐渐降低的趋势，而幼鱼后期则表现为先升高后降低的势。3．植物蛋白酶解物对异育银鲫肠道发育的影响采用石蜡切片法和免疫组织化学法，对异育银鲫的肠道组织形态和G细胞分布密度进行观察，以研究棉粕、豆粕蛋白酶解物对肠道发育的影响及其作用机理。选用异育银鲫1龄鱼种360尾，平均初重为35.05g，随机分为3组，每组设3个重复。其中Ⅰ为对照组，饲喂基础日粮，Ⅱ、Ⅲ为试验组，其饵料在基础日粮基础上，分别用3％棉粕蛋白酶解物和3％豆粕蛋白酶解物替代相应比例的棉粕和豆粕，并保证其粗蛋白水平不变。正式试验120d。结果表明：与对照组相比，Ⅱ、Ⅲ组试验鱼肠道横截面积显著增大(P＜0.01)，肠长虽有增长趋势，但差异不显著(P＞0.05)；而肠道组织形态均发生显著变化，粘膜皱襞个数、皱襞高度、粘膜皱襞高度／肌层厚度，单位长度肠道粘膜面积均增大，其中皱襞个数差异显著(P＜0.05)，其余三个形态学指标分别与对照组差异极显著(P＜0.01)；与对照组相比，两个试验组异育银鲫肠道G细胞分布密度均有所提高，其中棉粕蛋白酶解物组差异显著(P＜0.05)，豆粕酶解物组差异不显著(P＞0.05)。更多还原

【Abstract】 In order to provide scientific evidence for the farther study on digestive physiology in carps, the intestinal histology, morphology and G cells distributive density in Allogynogenetic crucian was observed firstly, and then the intestine was compartmentalized according to the observational results; secondly, the intestinal histology and morphology varieties of Allogynogenetic crucian in different developing phases were studied; at last, the effects of cottonseed meal hydrolysates and Soybean meal hydrolysates on the growth of Allogynogenetic crucian and the mechanism were discussed. This study consists of three parts as follows:1. The observation on histology and morphology of the intestine and the study on the intestinal function in Allogynogenetic crucianAllogynogenetic crucian was researched in this experiment whose intestinal histology and Gastrin positive reactive cells’ distributions in the gut mucosa were examined through paraffin slice and immunohistochemistry with the purpose to study each intestinal part’s function in fishes without stomach. The results indicated that there were evident varieties in the sizes of the tunnels, in the thicknesses of musculature, and even in the duplicatures’ numbers, heights, and widths; among them the size of the tunnel and duplicatures’ number decreased gently from the foreside to the end; Gastrin positive reactive cells could be found everywhere in the mucosa along the whole gut of Allogynogenetic crucian except the part which was close to the anus, and the cells’ distributive density decreased along the gut from the foreside to the end. According to the results, the gut can be compartmentalized into fore-gut, mid-gut, hind-gut and rectum; the percentages of each part to the whole length are 13.44%±2.19%, 39.42%±0.70%, 38.64%±1.94% and 8.50%±1.02%. 2. The study on the intestinal histology and morphology varieties in different developing phases of Allogynogenetic crucianThe foregut, midgut and hindgut’s intestinal histology and morphology in 3 develop periods (prophase-young, anaphase-young and adult) of Allogynogenetic crucian were observed, with the purpose studying the varying characters of the intestinal histology and morphology in different develop periods. The results showed as follows: the varying trends of duplicature’s number, duplicature’s width, musculature’s thickness and tunnel’s size had been the same respectively in 3 develop periods; among them, duplicatures’ numbers increased from foregut to midgut and decreased down to hindgut all the time in 3 develop periods; duplicature’s width in foregut were still bigger than the other parts of the intestine all the time, and there was no difference between the midgut and the hindgut (P>0.05); both musculature’s thickness and tunnel’s size decreased from foregut to hindgut all in 3 develop periods; but the varying trends of duplicature’s height were changed in 3 develop periods; the varying trends in anaphase-young increased from the foregut to the midgut and decreased down to the hindgt while the varying trends in prophase-young and adult both decreasing from the foreside to the end.3. The study on plant protein hydrolysates’ effects on the intestinal development of Allogynogenetic crucian.The effects of the cottonseed meal hydrolysates and Soybean meal hydrolysates on growth performance were investigated in Allogynogenetic crucian through paraffin slice and immunohistochemistry in order to study its action mechanism. 360 fishes (initial weight ca.35.05g) were used in this trail. Experiment fishes were divided into three groups randomly and the fishes in the same group were fed in three aquatic cases (40 fishes/ case). Group I were fed with basic diet; group II and group III were fed with the basic diet with 3% cottonseed meal hydrolysates and 3% soybean meal hydrolysates in stand of 3% cottonseed meal and 3% soybean meal respectively. Period of this trail was 120 days. The results showed as follows: the intestine length in group II and group III had been longer, but were not different to group I (P>0.05); cross section area in group II and group III were bigger significantly than the one in group I (P<0.01); intestinal histology and morphology varied, contrast to group I , duplicature’s numbers, duplicature’s heights, duplicature’s height/ musculature’s thicknesses and intestinal mucous membrane’s areas of group II and group III were both increased, duplicature’s numbers were different(P<0.05), others were significantly (P<0.01); the G cells distributive density of group II and group III had also increased, group II was significantly different (P<0.05), but group HI had no difference (P>0.05).更多还原