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1.
徐卫丹  陈安国 《饲料工业》2003,24(12):16-21
1前言断奶仔猪随意采食量的低下以及与之相联系生长性能的降低是阻碍养猪生产提高效率的主要限制因素。虽然在断奶仔猪营养、行为、卫生和环境等各个方面研究取得了很大进展,然而断奶后生长停滞仍然是困扰我们的一大难题。断奶后肠道结构和功能显著变化,如绒毛萎缩和隐窝增生与断奶仔猪生长性能下降有着密切的关系,这经常被认为是小肠消化和吸收能力的暂时下降,然而断奶后导致这些变化准确的病因还不确定。本文综述了断奶仔猪小肠生理和生化特性以及影响小肠结构和功能的因素。2断奶仔猪小肠的结构和功能2.1绒毛高度和隐窝深度断奶后绒毛萎…  相似文献   

2.
断奶仔猪成活率低的原因与解决对策   总被引:1,自引:0,他引:1  
正断奶仔猪成活率是猪场关注的关键环节,分析断奶仔猪成活率低的原因及采取相应的对策从而不断提高断奶仔猪成活率,才能更好地提高猪场的经济效益,笔者经几年兽医临床仔猪管理经验总结出断奶仔猪成活率低的原因与对策,现介绍如下。1断奶仔猪成活率降低的原因1.1生理因素1.1.1断奶仔猪的小肠结构变化仔猪断奶后小肠出现严重的绒毛萎缩、隐窝变深,造成小肠吸收  相似文献   

3.
试验选用60头21d断奶、体重均一的杜长大仔猪。按单因素完全随机化设计随机分为2组,一组为对照组,饲喂基础日粮;一组为试验组,基础日粮添加0.5%的谷氨酰胺,研究谷氨酰胺处理对断奶仔猪小肠黏膜形态变化的影响。在断奶当天及断奶后7d和14d每个处理随机选取3头仔猪屠宰,取小肠组织,测定肠黏膜的形态结构变化。结果表明:日粮中添加谷氨酰胺提高了小肠绒毛高度和固有层厚度及皱褶深度。  相似文献   

4.
袁森泉 《广东饲料》2002,11(2):21-22
有关刚断奶仔猪的行为、环境、健康和营养方面可供利用的资料很多。因断奶仔猪小肠的结构和功能在断奶后几天发生变化,造成消化吸收能力降低,这可部分地造成断奶后生长阻滞。而健康可能与小肠的结构和功能得到改善有关。  相似文献   

5.
断奶应激对仔猪肠黏膜形态的影响   总被引:3,自引:0,他引:3  
在仔猪断奶过渡期,胃肠结构受损是很普遍的,断奶后一段时间内,胃肠结构受损程度不同,本文研究了断奶后7d内(断奶后0-6d),仔猪小肠黏膜形态的变化,试验仔猪28日龄断奶。试验分7组,每组6头仔猪。从断奶当天开始,每1d定时定点剖杀取小肠前段,小肠中部,小肠后段作组织切片,观察其绒毛高度,隐窝深度。结果表明,断奶后前4d,绒毛高度缩短,隐窝加深,断奶后第4d绒毛高度最短,断奶后第5d开始恢复。  相似文献   

6.
<正>仔猪消化道内的适宜酸度是维持消化系统正常功能不可或缺的重要因素之一。早期断奶仔猪由于消化系统发育尚不成熟,神经和内分泌调控机制还未完全建立,因而在断奶后3~4周内,仔猪消化道内的p H值反而高于断奶前的水平。断奶仔猪消化道中p H偏高,不但会影响小肠消化酶的活性,还会引发病原菌的增殖,导致仔猪出现营养性腹泻,并严重制约仔猪生产潜能的发挥。养猪生产中发现,在断奶仔猪日粮中添加酸化剂,可以增加仔猪消化道  相似文献   

7.
本研究旨在探讨饲粮中添加酵母壁多糖对断奶仔猪生长性能和小肠黏膜形态结构的影响。试验采用单因素试验设计方法,选取180头遗传背景一致、健康状况良好、胎次和体重接近的21日龄断奶仔猪,随机分为4个组,每组5个重复,每个重复9头猪。4个组分别饲喂对照饲粮、0.15%酵母壁多糖饲粮、0.30%酵母壁多糖饲粮和0.45%酵母壁多糖饲粮。试验期21 d。结果表明:1)与对照组相比,饲粮中添加酵母壁多糖能够显著提高断奶仔猪平均日增重和平均日采食量(P0.05);酵母壁多糖有降低断奶仔猪腹泻率和料重比的趋势,但差异不显著(P0.05)。2)与对照组相比,饲粮中添加酵母壁多糖能够显著提高断奶仔猪空肠绒毛高度/隐窝深度值(P0.05),添加0.45%酵母壁多糖能够显著提高断奶仔猪空肠绒毛高度和十二指肠绒毛高度/隐窝深度值(P0.05)。由此可知,酵母壁多糖可提高断奶仔猪的生长性能,并改善小肠黏膜形态结构;综合生长性能、小肠黏膜形态及经济成本等指标,其在仔猪饲粮中的适宜添加量为0.30%。  相似文献   

8.
谷氨酰胺的生物学功能及其在断奶仔猪中的应用   总被引:2,自引:0,他引:2  
袁玖  姚军虎 《饲料工业》2005,26(8):8-11
文中概述了谷氨酰胺的营养生理功能及对动物机体免疫功能的影响。谷胺酰胺对早期断奶仔猪胰腺及小肠胰蛋白酶活性,肠道结构和功能,血浆内毒素水平,饲喂生大豆后肠道通透性的影响及对早期断奶仔猪腹泻的影响,以及对骨骼肌中DNA、RNA浓度的影响。  相似文献   

9.
本文主要综述了谷氨酰胺的合成和降解及其去向,并对谷氨酰胺对早期断奶仔猪免疫功能包括仔猪肠道结构和功能、小肠酶活性、抗氧化能力及腹泻的影响进行了探讨。  相似文献   

10.
改善早期断奶仔猪肠道环境和免疫状态的营养手段   总被引:5,自引:0,他引:5  
仔猪早期断奶时 ,由于受心理、环境及营养应激影响 ,常表现为食欲差、消化功能紊乱、腹泻、生长迟滞、饲料利用率低等所谓“仔猪早期断奶综合征”。因此 ,如何减少断奶应激对仔猪生长发育的影响一直是国内外动物营养和养猪专家众所关注的问题。本文根据国内外仔猪消化生理学方面的研究进展 ,探讨改善早期断奶仔猪肠道环境和免疫状态的营养手段。1 日粮消化率试验表明 ,日粮在猪消化道的不同部位停留的时间所占的比例分别为 :胃 1 5%~ 3 0 %,小肠 4 %~ 6%,大肠65%~ 80 %。胃和小肠是重要的消化器官 ,而小肠还是主要的吸收场所。试验表明 …  相似文献   

11.
Nutrient absorption occurs from the intestinal surfaces. Strategy in nutrient recovery by the small intestine is opposite to that of the large intestine. The duodenum, jejunum, and ileum have a very expansive mucosa by virtue of villi from the wall and microvilli on enterocytes, whereas the cecal body dominates the large intestine with its mucosa providing minimal surface area exposure to the lumen. Refluxive motility and villi movement in the small intestine provide ready convective contact between lumen contents and the unstirred water layer at the villi surfaces while contractile elements move microvilli to enhance contact after transfer into this surface. Refluxive motility in the colon gently separates fine from coarse particulates of small intestinal indigesta using urine moved from the urodeum. Cecal entry is restricted to fluid and fines by narrow orifices and protruding villi. Microbes in the small intestine are suppressed and reflect a bird's environment, whereas rapid motility favors aerobes because of oxygen exchange with the wall. Microbes in the large intestine are highly concentrated with low oxygen levels that support anaerobes. Plant fiber that has high proportions of cellulose lends to coarse particulates after feed manufacturing, whereas fiber high in hemicellulose-pectin combinations disintegrate and may be partially soluble. Fiber generally acts as a dietary diluent with coarse particulates being more rapidly evacuated than soluble nonstarch polysaccharides or fines. Soluble nonstarch polysaccharides that increase viscosity of the small intestine's luminal contents adversely affect live performance because of impaired efficiency of convection, reduced rate of exchange with the mucosa, and an expanded microbial population. Both nonstarch soluble fiber and the fine particulates are readily fermented to volatile fatty acids in the ceca that contribute to metabolizable energy.  相似文献   

12.
This paper deals with an unusually high incidence, i.e. 0.97 % of carcinoma of the small intestine found in Icelandic sheep. The tumours were situated in the jejunum and upper ileum. The macroscopic and microscopic pathology is described and compared with carcinoma of the small intestine of domestic animals and humans.Aetiological factors are discussed and the possibility of exposure to carcinogenic substances, especially nitrosamines in food concentrates, is suggested.Finally these findings are discussed in relation to current ideas on carcinogenesis in the intestines.  相似文献   

13.
应用透射电镜技术,对15只正常中华鳖小肠和大肠黏膜上皮细胞的超微结构进行了研究。结果表明,中华鳖小肠黏膜上皮为单层柱状上皮,以高柱状吸收细胞为主,具有发达的微绒毛、线粒体、粗面内质网和膜包小囊泡,其结构的发达程度已接近高等哺乳动物和鸟类。吸收细胞之间可见少量低电子密度的亮细胞,其种类需进一步确定。杯状细胞明显可见,胞质内含大量黏液性颗粒,细胞游离面形成明显的微绒毛。内分泌细胞很少。大肠黏膜上皮细胞排列松散,全部由上下粗细不均的柱状细胞组成。大肠上皮内未见专门的杯状细胞,但上皮细胞顶部胞质内含大量黏液颗粒,细胞器分布于黏液颗粒团之下的胞质中。细胞间隙宽大明显,有利于黏膜免疫细胞出入上皮。小肠和大肠均未见腺体分布。  相似文献   

14.
小肠是猪的主要消化吸收器官,对个体的生长发育非常重要,但到目前为止,国内外对猪小肠的研究还很少。为探讨其长度与生长发育性状之间的关系,本试验测定了白色杜洛克×二花脸资源家系F2和F3群体共计1 508头个体的240日龄小肠长度、出生重、21日龄体重、46日龄体重、0~46日龄平均日增重、46~240日龄平均日增重、240日龄平均日增重、240日龄宰前活重及屠宰后胴体直长、胴体斜长等10项生长性状指标,并对其与小肠长度的相关性进行了分析。结果显示猪240日龄小肠长度与这些生长性状都存在极显著相关(P0.001),表明小肠可能通过影响个体对营养成分的消化吸收而影响个体的生长发育。据我们所知,本试验是首次在大规模样本群体中研究猪小肠长度与生长发育性状的相关性,其结果为小肠和个体发育研究提供了重要参考。  相似文献   

15.
The small intestine is a vital organ in animal gastrointestinal system, in which a large variety of nutrients are absorbed. To identify quantitative trait loci (QTL) for the length of porcine small intestine, phenotypic values were measured in 1034 individuals at 240 d from a White Duroc × Chinese Erhualian intercross F2 population. The length of small intestine showed strong correlation with growth traits and carcass length in the F2 population. A whole‐genome scan was performed based on 183 microsatellites covering the pig genome in the F2 population. A total of 10 QTL for this trait were identified on 8 pig chromosomes (SSC), including four 1% genome‐wide significant QTL on SSC2, 4, 7 and 8, one 5% genome‐wide significant QTL on SSC12, and five 5% chromosome‐wide significant QTL on SSC5, 7, 13 and 14. The Erhualian alleles were generally associated with shorter length of the small intestine except the alleles on SSC7 and 13. The QTL on SSC4 overlapped with the previously reported QTL for the length of small intestine. Several significant QTL on SSC2, 8, and 12 were consistent with previous reports. The significant QTL detected on SSC7 was reported for the first time. All QTL identified in this study corresponded to the known region significantly associated with growth traits, supporting the important role of the length of small intestine in pig growth.  相似文献   

16.
Three segments of cattle small intestine (duodenum, upper jejuno‐ileum and lower jejuno‐ileum) were examined in an in vitro system for activity of ornithine carbamoyltransferase (OCT; EC 2.1.3.3) which is involved in the synthesis of citrulline (Cit) from ornithine (Orn). The mucosa of the three segments of small intestine was collected from Japanese black cattle, homogenized and then centrifuged. The supernatant fraction was used as the crude OCT enzyme solution. The OCT activity was assayed by the production of Cit from Orn determined directly by HPLC. The optimal pH and temperature for OCT activities in the duodenum, upper jejuno‐ileum and lower jejuno‐ileum of cattle small intestine were 7.47 and 39°C. Little difference was observed between the three segments. The OCT activity in cattle kidney was also examined for comparison, and almost no activity was found. The OCT activities in crude enzyme solutions of the three segments of small intestine were stable for up to one month of storage at ?20°C in Tris HCl buffer solution. Finally, the role of the small intestine in supplying Cit as a precursor for arginine synthesis in cattle kidney was discussed.  相似文献   

17.
Early weaning induces villous atrophy in the small intestine. Reduction in villous height in the small intestine after weaning is associated with reductions in brush‐border enzyme activity. Body weight gain after weaning is, therefore, correlated with villous height. This evidence suggested that the maintenance of small intestinal structure and function after weaning is important for the growth of young pigs. On the other hand, the relationship between villous height and the activity of the digestive enzymes in the small intestine has not been studied with piglets from the suckling to the growing period. Five suckling piglets, four piglets in the proximal stage of weaning, four pigs in the distal stage of weaning and four growing pigs were used. The activities of lactase (LA), sucrase (SA) and maltase (MA) were determined. LA showed a positive correlation with villous height in weaning. SA and MA were positively correlated with villous height from suckling to growing. In a previous study, non‐infectious dyspeptic diarrhea was frequently observed in growing piglets on Japanese swine farms. The maintenance of villous height to retain disaccharidase activity may prevent dyspepsic diarrhea in this stage.  相似文献   

18.
The equine small intestine is challenging to evaluate ultrasonographically. In humans, hydrosonography has been used to improve ultrasonographic images of the small intestine. We hypothesized that fasting horses for 24 h would enhance the ability to image the small intestine transabdominally by separating intestinal loops and reducing intraluminal gas, and that the administration of intragastric contrast agent would further improve that ability. Ten healthy horses were examined ultrasonographically under three treatment conditions: (a) regular diet, (b) after a 24‐h fast, and (c) fasted plus intragastric administration of water and mineral oil. During each phase of the study, 30‐s video clips were obtained from four predetermined abdominal windows, and were examined to determine diagnostic quality. Fasting improved the ability to obtain high‐quality images of the small intestine significantly. The addition of contrast agent resulted in qualitative improvement in image quality, but differences did not result in statistically significant improvement.  相似文献   

19.
试验选取6只1~1.5岁,体重(55.3±3.8)kg,装置永久性十二指肠近端T型瘘管和回肠末端T型瘘管的小尾寒羊公羊,收集十二指肠和回肠食糜,通过自身对照试验,研究在精料型(玉米秸秆占30%)日粮条件下添喂气溶胶OT(0.8 g/kg日粮)对小尾寒羊前胃和小肠消化吸收的影响。结果表明,添喂气溶胶OT使小尾寒羊干物质自由采食量增加23.6%(P<0.01)。前胃干物质、有机物、粗蛋白质和纤维素的消化量分别增加39.2%(P<0.01)、37.3%(P<0.01)、21.8%(P<0.01)和13.4%(P<0.01);到达小肠的干物质、有机物、粗蛋白质、微生物蛋白质和过瘤胃蛋白质分别增加8.9%(P<0.01)、8.8%(P<0.01)、21.3%(P<0.01)、29.3%(P<0.01)和13.1%(P<0.01);总氨基酸、赖氨酸、蛋氨酸、苏氨酸、缬氨酸和苯丙氨酸分别增加45.6%(P<0.01)、62.7%(P<0.01)、40.8%(P<0.01)、32.8%(P<0.01)、32.0%(P<0.01)和32.3%(P<0.01)。小肠干物质、有机物、粗蛋白质、钙和磷消化吸收量分别增加28.7%(P<0.01)、29.8%(P<0.01)、28.7%(P<0.01)、26.6%(P<0.01)和13.1%(P<0.01);小肠总氨基酸、赖氨酸、蛋氨酸、异亮氨酸、精氨酸和组氨酸消化吸收量分别增加37.6%(P<0.01)、56.9%(P<0.01)、28.6%(P<0.01)、40.9%(P<0.01)、41.5%(P<0.01)和51.7%(P<0.01)。由以上得出结论,添喂气溶胶OT可以提高小尾寒羊自由采食量,增加前胃和小肠营养物质消化吸收量,显著改善宿主的营养供应。  相似文献   

20.
羔羊小肠pH及主要消化酶发育规律的研究   总被引:13,自引:2,他引:13  
对小尾寒羊羔羊小肠不同部位(十二指肠、空肠和回肠)pH及淀粉酶、胰蛋白酶、糜蛋白酶、脂肪酶和乳糖酶的活性进行了测定,结果表明:羔羊小肠不同部位内容物pH不同,回肠pH显著高于空肠,空肠和回肠pH显著高于十二指肠,羔羊1月龄后,小肠各段pH变化不大;小肠不同部位淀粉酶和胰蛋白酶、糜蛋白酶及脂肪酶活性不同,空肠段淀粉酶、胰蛋白酶、糜蛋白酶及脂肪酶活性高于十二指肠和回肠段,随着羔羊日龄的增长,小肠淀粉酶、胰蛋白酶、糜蛋白酶及脂肪酶活性增加,3月龄后各消化酶活性变化差异不显著(P<O.05);羔羊小肠不同部位乳糖酶活性不同,空肠乳糖酶活性显著高于十二指肠和回肠,随着羔羊日龄的增长,小肠乳糖酶活性逐渐降低。  相似文献   

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