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51.
为探讨饲粮粗蛋白质水平对鲁西斗鸡肠道发育的影响,并建立肠道发育的生长模型,试验选用1日龄鲁西斗鸡雏鸡600只(公母各半),随机分为5个处理,每个处理6个重复,每个重复20只。试验分为0~6、7~12、13~18、19~24周4个阶段,采用单因子试验设计,各处理组分别饲喂不同蛋白质水平的饲粮。在6、12、18、24周末,每重复屠宰1只进行肠道指标的测定。结果表明:(1)饲粮粗蛋白质水平对6、12、18、24周末十二指肠、空肠及回肠长度和重量均无显著影响(P>0.05);(2)鲁西斗鸡十二指肠、空肠及回肠重量随周龄变化符合Logistic模型。  相似文献   
52.
选择大小、体重相近的SD雌性小鼠(18~22g)40只,随机分为4组,1.5%"和胃平喘"组、2.5%"和胃平喘"组、3.5%"和胃平喘"组和基础料组,每组2个重复,每个重复5只,分别饲喂15d和30d后取肠道做成切片,测定小鼠肠道的肠绒毛高度。结果表明:15d试验中,1.5%"和胃平喘"组、2.5%"和胃平喘"组、3.5%"和胃平喘"组与对照组间的平均肠绒毛高度差异显著(P0.05)。30d试验中,2.5%"和胃平喘"组十二指肠平均肠绒毛(duodenum villus)高度为0.9835±0.1582mm,3.5%"和胃平喘"组十二指肠平均肠绒毛高度为0.8898±0.1635mm,2.5%"和胃平喘"组、3.5%"和胃平喘"组的十二指肠平均肠绒毛高度都与对照组的差异极显著(P0.01),1.5%"和胃平喘"组的十二指肠平均肠绒毛高度低于对照组,但差异不显著(P0.05);2.5%"和胃平喘"组和3.5%"和胃平喘"组的空肠平均肠绒毛(jejunum villus)高度与对照组间的差异不显著(P0.05);1.5%"和胃平喘"组和2.5%"和胃平喘"组的回肠平均肠绒毛(ileum villus)高度与对照组间的差异不显著(P0.05)。在小鼠基础料中添加"和胃平喘"能不同程度提高小鼠肠绒毛高度,且以2.5%和3.5%两个添加量效果最好。  相似文献   
53.
Color Doppler ultrasonography was performed in 15 young dogs with intestinal intussusception to test the hypothesis that color Doppler findings can be used as a predictor of the manual reducibility of the intussusception at celiotomy. Color flow Doppler ultrasonography indicated blood flow within mesentery of the intussuscepted bowel in 12 of 15 dogs and reduction was achieved in nine of these 12 dogs (75%). In the remaining three dogs and in three dogs where no color Doppler signal were observed, an irreducible intussusception was confirmed at celiotomy. Color Doppler ultrasonography is a useful method for predicting the reducibility of intussusception in dogs.  相似文献   
54.
不同脱乙酰度壳聚糖对肉仔鸡肠道菌群的影响   总被引:1,自引:0,他引:1  
1日龄AA肉仔鸡250只,随机分为5组,每组设5个重复,每个重复10只鸡。对照组(Ⅰ)喂给基础日粮,试验组(Ⅱ、Ⅲ、Ⅳ、Ⅴ)分别在基础日粮中添加脱乙酰度为82.5%、86.2%、90.5%和95.3%的壳聚糖10g/kg。试验期7周。试验结果表明:不同脱乙酰度壳聚糖对肉仔鸡肠道菌群的影响不同,在21日龄,脱乙酰度82.5%壳聚糖组能显著抑制盲肠大肠杆菌的增殖(P<0.05),各壳聚糖组均能不同程度地促进盲肠乳酸杆菌、双歧杆菌的增殖,其中脱乙酰度90.5%、95.3%壳聚糖组对双歧杆菌数量的影响差异显著(P<0.05);35日龄,各组盲肠大肠杆菌和双歧杆菌数量无显著差异;脱乙酰度82.5%和86.2%壳聚糖组与对照组相比能促进盲肠乳酸杆菌的增殖,且差异显著(P<0.05)。  相似文献   
55.
56.
The purpose of this experiment was to study the usage and proportion of fermented feed in broiler feed.By adding 0,10% and 20% fermented complete formula feed to the broiler feed,and granulating normally,the influence of the usage mode of the fermented feed on the production performance,slaughter performance,intestinal tract and other related indexes of the broiler feed were studied,so as to provide reference for the application of the fermented feed in the broiler feed.180 1-day-old healthy AA male broilers were randomly divided into 3 groups with 6 replicates in each group and 10 chickens in each replicate.The three treatment groups were fed with 0,10% and 20% of the total fermented feed for 42 days.The results showed that:From the whole period (1-42 days old),the 10% fermentation feed substitution group significantly reduced the feed consumption and weight gain ratio (P<0.05),and the average daily weight gain increased (P=0.05).At 42 days old,there was no significant effect of fermented feed on slaughter performance (P>0.05).The ileal crypt depth of broilers in the 20% fermentation feed replacement group was significantly higher than that in the control group and the 10% replacement group (P<0.05).The length of duodenal villi and V/C in 20% and 10% fermentative feed substitution group was significantly higher than that in control group (P<0.05).The results showed that the replacement of 10% fermented feed in broiler feed could reduce the ratio of feed to weight gain,increase the average daily gain,and have a certain impact on intestinal development.  相似文献   
57.
丁酸梭菌对肠道上皮细胞黏附及对鳗弧菌抑制的研究   总被引:4,自引:0,他引:4  
本试验以鱼肠道上皮细胞为模型,以肠道的致病鳗弧菌为对照,研究了丁酸梭菌对鱼肠道上皮细胞的黏附作用及黏附对细胞的损伤和成活率的影响。结果表明∶丁酸梭菌对鱼的肠道上皮的黏附率为7.39±1.85,低于鳗弧菌的黏附率(P<0.05);对细胞的损伤率为1.02±0.35,显著低于鳗弧菌对细胞的损伤率(P<0.05);黏附后丁酸梭菌组对细胞的成活率的影响与正常对照组比较,差异不显著;当酪酸菌、鳗弧菌与肠道上皮细胞共同培养时,使鳗弧菌的黏附率下降7.03%(P<0.05)。因此,该株丁酸梭菌可以安全地黏附鱼肠道上皮细胞,并能有效抑制鳗弧菌的黏附。  相似文献   
58.
A male, 5-year-old Jindo dog underwent enterectomy and enteroanastomosis due to ileus of the intestine at a local veterinary hospital. Grossly, the excised intestine showed markedly thickened multinodular masses in the serosal layer of the upper part, and soft-to-firm, cream-colored neoplastic masses that displayed extensive nodular mucosal protuberances into the lumen. The neoplastic masses were filled with large round cells that were ovoid in shape and they had pale and/or hyperchromatic nuclei. The neoplastic cells had mainly infiltrated into the mucosal and submucosal layers, and they had diffusely invaded the muscular and serosal layers. Therefore, the diagnosis of canine multiple intestinal malignant lymphomatous polyposis was made based on the gross and histopathological findings. The origin of these tumor cells was determined to be B-cells since they were positive for anti-CD20.  相似文献   
59.
肉鸡肠道PepT1 mRNA表达的肠段差异性与发育性变化   总被引:1,自引:0,他引:1  
选用遗传背景相同的1日龄父母代雄性Arbor Acre(AA)鸡和父母代雄性岭南黄肉雏鸡各120羽,采用相对定量RT-PCR方法,以30 d时岭南黄鸡肠道样品为模板,研究肉鸡肠道寡肽转运载体1(Peptide transporter 1,PepT1)mRNA表达的肠段差异性;以AA肉鸡和岭南黄鸡十二指肠和空肠样品为模板,研究不同品种肉鸡肠道PepT1 mRNA表达的发育性变化。结果显示:(1)岭南黄肉鸡肠道PepT1 mRNA的表达丰度从十二指肠、空肠、回肠到结直肠依次降低,其中十二指肠显著高于结直肠(P<0.05);(2)AA鸡和岭南黄肉鸡PepT1 mRNA在十二指肠及空肠中的表达具有相同的发育模式,16 d表达丰度最高,16~44 d逐渐下降,58 d略微回升;不同基因型之间PepT1 mRNA丰度比较,AA鸡和岭南黄肉鸡两品种间PepT1 mRNA的表达没有显著差异(P>0.05)。以上结果说明:(1)随着肠道空间位置的后移,岭南黄肉鸡肠道PepT1 mRNA的表达丰度逐渐降低,其中十二指肠的表达丰度显著高于结直肠(P<0.05);(2)不同品种肉鸡十二指肠及空肠PepT1 mRNA的表达具有相同的发育模式,且同日龄两品种间的表达丰度未见明显差异,表明PepT1 mRNA表达受到发育阶段的调控,但品种间具有稳定性。  相似文献   
60.
This paper examines the possibility that treatment of diarrhoea with conventional oral rehydration solutions (ORSs) may be detrimental to villus structure by imposing nutrient deprivation and that such detrimental effects may be reduced or avoided by using a nutrient ORS. A conventional WHO-type ORS (W) was compared with two nutrient solutions (N and G) both containing high glucose concentrations and the latter containing glutamine; their effects on enteric structure were assessed by morphometric analysis of samples obtained from diarrhoeic calves after 96h treatment. Comparisons were also made with samples from controls and diarrhoeic calves at the stage where oral rehydration would have begun in the treated groups. As in our previous ORS studies, diarrhoea was induced with enterotoxigenic Escherichia coli (09:K30:K99). We measured villus length and width, crypt depth and width and calculated villus surface area in proximal, mid and distal small intestine (PSI, MSI, DSI), using standard morphometric techniques. Proximal and distal spiral colon samples (PC, DC) were examined for crypt depth and width; mitoses per crypt were counted in samples from all regions. Non-diarrhoeic calves showed the expected gradient of villus length through PSI, MSI and DSI, hence data for each region are normalized as a percentage of the control value for that region. PSI showed the greatest loss of villus length and surface area (50%) with diarrhoea. In MSI and DSI the villus loss was greater with solution W and N or G, as were increased mitoses and crypt depth. Crypt depth and mitoses also increased in the colon with solution W. Colonic crypt width increased with diarrhoea and conventional oral rehydration but less so with G; there is reason to believe that such changes have functional significance. Crypt changes in colon, MSI and DSI were least with solution G. The changes developing in diarrhoeic calves prior to treatment were thus less apparent in those treated with a nutritional ORS, particularly if it contained glutamine.  相似文献   
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