寡糖对断奶仔猪肠道内环境的作用及其应用研究

本文就仔猪消化道微生物区系的建立,早期断奶后仔猪消化道微生物区系的改变,寡糖对仔猪肠道内环境的调节作用及其在断奶仔猪生产上的应用研究作一阐述。     

低聚糖对早期断奶仔猪消化道微生物区系的调节作用

仔猪早期断奶后消化道微生物区系的改变是导致早期断奶综合症的重要原因之一。低聚糖是近年来国外开发的一种绿色饲料,它们不能被动物自身的消化酶所分解,但能被消化道中有益菌选择利用,因而具有调节消化道微生物区系的作用。     

复方中草药制剂对早期断奶仔猪免疫指标、抗氧化指标的影响

<正>仔猪断奶后出现的一系列生理变化导致的抗病力和免疫力下降、生产性能下降是应激、环境、日粮改变、消化道微生物区系紊乱等多种因素综合作用的结果,这就决定了抗生素作用的局限性。在改善仔猪健康状况和生产性能的一系列措施中,通过中草药复方饲料添加剂改善消化道微生物区系、促进营养物质吸收和利用、提高仔猪免疫能力,是以改善仔猪自身生     

早期断奶仔猪胃肠道微生物区系的日粮调控

仔猪胃肠道微生物区系的平衡对维持健康起熏要作用。为预防断奶仔猪消化功能失调和胃肠道疾病，了解早期断奶仔猪胃肠道微生物区系的变化是非常必要的。本文就胃肠道微生物区系对仔猪消化功能的影响以及潜在的日粮调控胃肠道微生物区系方法作一概述。     

日粮因素对断奶仔猪肠道微生物区系影响研究进展

介绍断奶仔猪肠道微生物区系特点,并对日粮中不同来源的蛋白、淀粉、脂肪、高锌高铜饲料添加剂、抗生素和酶制剂对断奶仔猪肠道微生物区系影响展开综述,为生产中通过日粮调控断奶仔猪肠道微生物菌群提供依据。     

酸奶治疗新断奶仔猪腹泻一例

断奶仔猪腹泻的原因主要是断奶应激,出生后抗体水平低下,肠道对饲料蛋白的过敏反应及胃内pH高,造成消化道微生物区系受破坏等,并论述了相应的综合防制措施.     

早期断奶仔猪腹泻发生的原因及预防措施

阐述了早期断奶仔猪腹泻的原因主要是断奶应激 ,出生后抗体水平低下 ,肠道对饲料蛋白的过敏反应及胃内pH高 ,造成消化道微生物区系受破坏等 ,并论述了相应的综合防制措施     

浅议早期断奶仔猪的营养调控

在养猪生产中 ,仔猪生产是关键的一环。仔猪早期断奶是国内外集约化养猪生产中普遍关注的先进技术 ,但仔猪早期断奶易受环境和营养等多种因素的应激影响 ,引起“仔猪早期断奶综合症”。因此对早期断奶仔猪进行营养调控 ,配制适宜饲粮是防止仔猪早期断奶综合症和提高仔猪成活率和育成率的有效方法之一。1　早期断奶仔猪的消化生理特点据报道 ,仔猪在早期断奶时 ,其消化道的发育情况、消化酶活性的变化及胃肠道的微生物区系等都会影响仔猪消化能力及免疫机能。1 .1　消化道发育　仔猪在哺乳期间 ,胃内因乳酸的存在而 p H值较低。断奶后由于乳…     

仔猪消化道微生物区系变化影响因素研究

本文简述仔猪消化道微生物区系的组成及结构，重点分析影响消化道微生物区系变化的各种因素，表明正常的微生物区系的建立对维持仔猪健康生长具有重要作用。     

活性酵母对断奶仔猪生长性能及消化道微生物区系的影响

选取180头21日龄断奶的杜长大杂种仔猪,按体重随机分为5组,每组6个重复,每个重复6头仔猪。其中对照组饲喂基础饲粮,4个试验组分别在基础饲粮的基础上添加10mg/kg黄霉素、0.05%活性酵母、0.10%活性酵母、0.15%活性酵母,探讨活性酵母能否替代抗生素及其在断奶仔猪饲粮中的最适添加量和活性酵母对消化道微生物区系的影响。结果表明,饲粮中添加活性酵母可以替代抗生素,且添加0.10%的效果最佳,饲粮中添加酵母菌制剂可以改善消化道微生物区系。     

仔猪消化道菌群变化与仔猪腹泻的关系

通过对健康和腹泻仔猪消化道内(胃、十二指肠、空肠、回肠、盲肠、结肠和直肠)7个部位菌群取样后进行培养和分离鉴定，研究健康和腹泻仔猪间不同菌群关系的差异，揭示维持仔猪的正常消化代谢优势菌群的组成、比例和结构。结果发现：双歧杆菌和乳杆菌是健康仔猪消化道内数量最多的菌群，为优势菌群；韦荣氏球菌、肠杆菌、肠球菌在仔猪发生腹泻时明显增多，为有害菌群。有害菌群的增多抑制了有益优势菌群的生长，从而导致仔猪发生腹泻。     

Investigations on prophylactic effects of coarse feed structure and/or potassium diformate on the microflora in the digestive tract of weaned piglets experimentally infected with Salmonella Derby

The purpose of this study was to examine potential prophylactic effects of a coarse feed structure and/or potassium diformate (KDF as feed additive) addition to diets on the microflora of the digestive tract in reared piglets experimentally infected with Salmonella Derby. The results show that coarse grinding as well as KDF addition are able to influence positively the intestinal flora and are capable to reduce Salmonella excretion of infected piglets. Coarse grinding of main ingredients (e.g. cereals) led to an increased number of lactobacilli as well as to higher counts of Gram-positive coccoid bacteria in the colon chyme, while KDF resulted in a tendency towards lower counts of Escherichia coli within the digestive tract. Moreover, a combination of both treatments influenced the composition of the gastrointestinal flora quite positively. Furthermore, the combination of these dietetic measures resulted in a reduced Salmonella excretion rate, shorter Salmonella shedding period and a reduced translocation of Salmonella within the infected piglets. The positive effects of combining both treatments led to a significantly reduced spreading of Salmonella within the group of pigs, which might be used to diminish Salmonella prevalence in pig production.     

家畜消化道菌群的分子生物学研究方法

消化道菌群多样性对于维持家畜机体健康起着至关重要的作用,因此,对家畜消化道中定植菌群的种类和功能进行分析就显得尤为关键。由于所有动物的消化道是厌氧环境,所以在体外的好氧环境中,有些菌种不易培养,而这些菌种信息的缺失,会导致消化道优势菌群的分析结果出现偏差。借助一些广泛应用的分子生物学研究方法,可以避免这种情况的发生。这些方法主要是测序法和定性定量分析法。测序法包括指纹图谱法和高通量测序法,定性定量分析法包括荧光原位杂交法和实时荧光定量PCR法。这些方法均基于分子生物学水平,可避免菌体培养步骤,直接分析消化道菌群的组成和功能。综述了上述方法的原理以及各自的优点和缺点,并对它们在动物消化道菌群多样性分析中的应用进行了讨论,以期为研究动物消化道微生物时不同分子生物学方法的选择和联合使用提供参考。     

益生菌及寡糖对猪肠道乳酸菌群多样性的影响

断乳初期仔猪肠道乳酸菌群多样性容易发生改变,这种改变会使仔猪变得更加易感。乳酸菌和寡糖的饲喂可以促进仔猪肠道乳酸菌群多样性的恢复,更加有利于提高仔猪对肠道疾病的抵抗性。不同的益生菌种促进肠道乳酸菌群多样性的能力不同,这就为乳酸菌的筛选提供了一种新思路。另外,不同的寡糖也可被不同的益生菌所利用,因此,益生菌与寡糖的配合应用要有所选择。     

转基因猪中抗生素标记基因neo漂移风险评估

本试验旨在研究转基因猪中抗生素标记基因neo漂移的可能性。利用Southern blotting鉴定F1代仔猪的显隐性,结果发现6头仔猪中有3头为转基因仔猪,3头为阴性仔猪。通过PCR技术对试验仔猪血液和消化道组织中neo基因进行检测,结果发现neo基因没有在血液水平和消化道组织中发生漂移。通过PCR技术对试验仔猪肠道细菌中neo基因进行检测,在肠道细菌基因组中没有检测到neo基因的存在。检测结果表明,仔猪血液、肠道细菌和消化道组织等都没有发生neo基因的漂移。     

Risk Assessment of Antibiotic Marker Gene neo Drifts in Transgenic Pigs

This study was designed to study the possibility of gene drift of the antibiotic marker gene neo in transgenic pigs.First,dominance and recessiveness of neo gene in 6 piglets of F1 were identified using Southern blotting.It was found that 3 piglets were positive transgenic piglets and the other 3 piglets were non-transgenic piglets.The neo gene in blood and digestive tract tissue of experimental piglets were detected using PCR.The result showed that no gene drift was showed in blood and digestive tract tissues of experimental piglets.Then PCR technology was used to detect neo gene in intestinal bacteria of experimental piglets.The result showed that neo gene did not exist in the genome of intestinal bacteria.This study suggested that no gene drift was found in blood,intestinal bacteria and digestive tract tissues of piglets.     

Multiplication of low and high cell culture passaged strains of transmissible gastroenteritis virus in organs of newborn piglets

Distribution and persistence of four different strains of transmissible gastroenteritis (TGE) virus in newborn piglets were compared.The piglets inoculated with high-passaged TO-163 strain did not show any clinical signs of TGE on any days postinoculation (DPI), but the piglets inoculated with one of the other three strains, SH-14, SH-164 or TO-16, had soft feces or diarrhea. In the latter cases, the virus was isolated mainly from respiratory organs, lymph nodes, and digestive tract on any DPI, but was rarely detected in the digestive tract of piglets inoculated with the TO-163 strain. The frequency of virus recovery from the tissues was the highest till 4 DPI in all of the piglets inoculated with one of the four virus strains, and it was markedly reduced thereafter in the piglets inoculated with high-passaged strains.The TO-163 strain was subjected to serial passage in newborn piglets for seven passages. There was no evidence of regained pathogenicity with advance in passage, and detection of virus was restricted to lymph nodes and lung of these piglets.In gnotobiotic piglets inoculated with the TO-163 strain, frequent virus recovery and high titers of virus from the tissues were obtained on up to the 4th DPI. The viruses in high titer were found in the digestive tract of some of the piglets; however, none of them showed any clinical signs of TGE.     

Probiotics in animal nutrition: a review

The normal microflora colonizing the digestive tract in livestock species at five to six days after birth can be summarized as following: 400 to 500 different bacterial strains for a total count of 10(14) bacteriae. The role of the gut flora is multifarious: fermentation of feed compounds, induction of anatomical and physiological changes in the intestinal cell wall structure, increase in animal resistance against enteropathogenic bacteriae, etc. In the present review, the numerous hypotheses for explaining the beneficial effects of probiotics on zootechnical performances and also the healthy aspects for men and animals are summarized, and the possible mechanisms of bacterial attachment are enumerated. The different assumptions on mode of action and fixation mechanisms of probiotics in the gut are critically discussed, and the required characteristics of the ideal probiotic are listed. Finally, some zootechnical results obtained with lactic acid bacteria are shown for calves, piglets and broilers.     

断奶仔猪消化道酸度及其调控研究进展

本文综述了影响断奶仔猪消化道酸度发育的因素及其调控的研究情况 ,并指出仔猪消化道酸度研究领域存在的不足以及今后的主要方向     

Oral administration recombinant porcine epidermal growth factor enhances the jejunal digestive enzyme genes expression and activity of early-weaned piglets

This study attempted to determine ingested porcine epidermal growth factor (pEGF) on the gastrointestinal tract development of early-weaned piglets. Thirty-two piglets (14-day weaned) were randomly allotted to supplemented with 0 (control), 0.5, 1.0, or 1.5 mg pEGF/kg diet. Each treatment consisted of four replicates with two pigs per pen for a 14 days experimental period. Piglets were sacrificed and gastrointestinal tract samples were collected to measure mucosa morphology, mRNA expression and activities of digestive enzymes in the gastrointestinal tract of piglets at the end of the experiment. Diets supplemented with pEGF failed to influence growth performance but tended to increase jejunal mucosa weight (p < 0.09) and protein content (p < 0.07). Piglets supplemental pEGF induced incrementally the gastric pepsin activity (p < 0.05) and stimulated jejunal alkaline phosphatase (ALP) and lactase activities accompanied with the increase of jejunal ALP and maltase mRNA expression. No effect of pEGF on the activities of all enzymes in ileum except the stimulation of ileal aminopeptide N mRNA expression. These results reveal that dietary pEGF supplementation might enhance gene expression and activities of digestive enzymes in the stomach and jejunum of piglets.