Single-cell profiling of the pig cecum at various developmental stages

The gastrointestinal tract is essential for food digestion,nutrient absorption,waste elimination,and microbial defense.Single-cell transcriptome profiling of the intestinal tract has greatly enriched our understanding of cellular diversity,functional heterogeneity,and their importance in intestinal tract development and disease.Although such profiling has been extensively conducted in humans and mice,the single-cell gene expression landscape of the pig cecum remains unexplored.Here,single-cell RNA sequencing was performed on 45572 cells obtained from seven cecal samples in pigs at four different developmental stages(days(D)30,42,150,and 730).Analysis revealed 12 major cell types and 38 subtypes,as well as their distinctive genes,transcription factors,and regulons,many of which were conserved in humans.An increase in the relative proportions of CD8^(+)T and Granzyme A(low expression)natural killer T cells(GZMA^(low)NKT)cells and a decrease in the relative proportions of epithelial stem cells,Tregs,RHEX^(+)T cells,and plasmacytoid dendritic cells(pDCs)were noted across the developmental stages.Moreover,the post-weaning period exhibited an up-regulation in mitochondrial genes,COX2 and ND2,as well as genes involved in immune activation in multiple cell types.Cell-cell crosstalk analysis indicated that IBP6^(+)fibroblasts were the main signal senders at D30,whereas IBP6^(−)fibroblasts assumed this role at the other stages.NKT cells established interactions with epithelial cells and IBP6^(+)fibroblasts in the D730 cecum through mediation of GZMA-F2RL1/F2RL2 pairs.This study provides valuable insights into cellular heterogeneity and function in the pig cecum at different development stages.

Expression of Chicken Toll-Like Receptors and Signal Adaptors in Spleen and Cecum of Young Chickens Infected with Eimeria tenella

Toll-like receptors （TLRs） are a group of highly conserved molecules which initiate the innate immune response to pathogens by recognizing structural motifs of microbes. Understanding the changes in chicken Toll-like receptors （ChTLRs） and signal adaptors expression that occur with Eimeria tenella infection will help to elucidate the molecular basis of immune control of coccidiosis caused by Eimeria. The present study detected the dynamic changes in the expression of ChTLRs and associated signal adaptors in the spleen and cecum ofE. tenella-infected chickens during the early stage of infection. The results showed that the expression peak for ChTLRs, MyD88 and TRIF occurred at 12 h post-infection （hpi）, ChTLR3, ChTLRI 5 and MyD88 mRNA expression in the spleen ofE. tenella infected chickens were significantly higher （P〈0.05） than that of negative control chickens, and there were similar tendencies of these molecules expression in the cecum and spleen of E. tenella-infected chickens. The expression of MyD88 was upregnlated at four time points in the cecum of E. tenella-infected chickens. The results of this study indicate that ChTLR3, ChTLR15 and MyD88 play a role in young chickens infected with E. tenella.

Effects of Crude Extract of Poria cocos on the Tension of Jejunum and Cecum in Rabbits in vitro

[ Objective] This study aimed to investigate the effects of crude extract of Poria cocos on intestinal smooth muscle contraction of rabbits in vitro and re- veal the related mechanism. [Method] With in vitro experimental method, using the tension of jejunal and cecal smooth muscle as an indicator, 3.75, 7.50, 15.00, and 22.5 g/L crude extract of P. cocos were added into Tyrede＇s solution of jejunum and cecum tissues of rabbits to observe the effects of crude extract of P. cocos on motion dynamics of jejunum and cecum of rabbits. [ Result] The addition of crude extract of P. cocos could inhibit the contraction of jejunal and cecal smooth muscle of rabbits in vitro, enhance contraction tension and relaxation tension, and reduce contraction amplitude. The effects were improved as the dose of crude extract of P. cocos increased, displaying a dose-effect relationship. [Condusion] This study provided theoretical basis for the clinical use of P. cocos.

Granular cell tumor of the cecum with extensive hyalinization and calcification:A case report

A granular cell tumor (GCT) is a benign neoplasm of unclear histogenesis that is generally believed to be of nerve sheath origin.GCT is not common and most often affects the tongue,skin and soft tissue,although it may occur anywhere in the body.We experienced a case of GCT that arose in the cecum of a 55-yearold man.The GCT was removed by laparoscopic resection.In addition to the tumor,endoscopic examination revealed the presence of a 5-mm-polyp in the descending colon and multiple tiny polyps in the sigmoid colon and rectum.Histological examination demonstrated a cecal tumor 1.5 cm × 1.0 cm × 0.7 cm with a hard consistency;in cut sections,mixed cells with yellowish and whitish portions were seen.The tumor was located between the mucosa and subserosa,and was composed of plump histiocyte-like tumor cells with abundant granular eosinophilic cytoplasm,which were immunoreactive for S-100 protein,vimentin,neuron-specific enolase,inhibin-α and calretinin.The tumor showed extensive hyalinization and focal dystrophic calcification.Immunohistochemical profiles did not confirm any particular cell type for the histogenetic origin of the GCT,including a nerve sheath origin.Extensive hyalinization and calcifi cation showing involution of tumor cells suggest benign clinical behavior of GCT.

Case of colonic intussusception secondary to mobile cecum syndrome repaired by laparoscopic cecopexy using a barbed wound suture device

A 27-year-old man with recurrent right lower quadrant pain was admitted to our hospital. Ultrasonography and computed tomography examination of the abdomen revealed a target sign in the ascending colon, which was compatible with the diagnosis of cecal intussusception. The intussusception was spontaneously resolved at that time, but it relapsed 6 mo later. The patient underwent a successful colonoscopic disinvagination; there was no evidence of neoplastic or inflammatory lesions in the colon and terminal ileum. The patient underwent laparoscopic surgery for recurring cecal intussusception. During laparoscopy, we observed an unfixed cecum on the posterior peritoneum(i.e. a mobile cecum). Thus, we performed laparoscopic appendectomy and cecopexy with a lateral peritoneal flap using a barbed wound suture device. The patient's post-operative course was uneventful, and he continued to do well without recurrence at 10 mo after surgery. Laparoscopic cecopexy using a barbed wound suture device is a simple and reliable procedure that can be the treatment of choice for recurrent cecal intussusception associated with a mobile cecum.

Counteraction of perforated cecum lesions in rats: Effects of pentadecapeptide BPC 157,L-NAME and L-arginine

AIM To study the counteraction of perforated cecum lesion using BPC 157 and nitric oxide(NO) system agents.METHODS Alongside with the agents' application(after 1 min, medication(/kg, 10 ml/2 min bath/rat) includes: BPC 157(10 μg), L-NAME(5 mg), L-arginine(100mg) alone or combined, and saline baths(controls)) on the rat perforate cecum injury, we continuously assessed the gross reappearance of the vessels(USB microcamera) quickly propagating toward the defect at the cecum surface, defect contraction, bleeding attenuation, MDA-and NO-levels in cecum tissue at 15 min, and severity of cecum lesions and adhesions at 1 and 7 d. RESULTS Post-injury, during/after a saline bath, the number of vessels was significantly reduced, the defect was slightly narrowed, bleeding was significant and MDA-levels increased and NO-levels decreased. BPC 157 bath: the vessel presentation was markedly increased, the defect was noticeably narrowed, the bleeding time was shortened and MDA-and NO-levels remained normal. L-NAME: reduced vessel presentation but not more than the control, did not change defect and shortened bleeding. L-arginine: exhibited less vessel reduction, did not change the defect and prolonged bleeding. In combination, mutual counteraction occurred(L-NAME + L-arginine) or the presentation was similar to that of BPC 157 rats(BPC 157 + L-NAME; BPC 157 + L-arginine; BPC 157 + L-NAME + L-arginine), except the defect did not change. Thereby at day 1 and 7, saline, L-NAME, L-arginine and L-NAME + L-arginine failed(defect was still open and large adhesions present). CONCLUSION The therapeutic effect was achieved with BPC 157 alone or in combination with L-NAME and L-arginine as it was able to consolidate the stimulating and inhibiting effects of the NO-system towards more effective healing recruiting vessels.

Fecal loading in the cecum as a new radiological sign of acute appendicitis

AIM： Although the radiological teatures of acute appendicitis have been well documented, the value of plain radiography has not been fully appredated. The aim of this study was to determine the frequency of the association of acute appendicitis with images of fecal loading in the cecum,METHODS： Plain abdominal radiographs of 400 patients operated upon for acute appendicitis （n = 100）, acute cholecystitis （n = 100）, right acute pelvic inflammatory disease （n = 100） and right nephrolithiasis （n = 100） were assessed. The presence of fecal loading was recorded and the sensitivity and specificity of this sign for acute appendicitis were calculated.RESULTS： The presence of fecal loading in the cecum occurred in 97 patients with acute appendicitis, 13 patients with acute cholecystitis, 12 patients with acute inflammatory pelvic disease and 19 patients with nephrolithiasis. The sensitivity of this sign for appendicitis was 97% and its specificity to this disease was 85.3%. Its positive predictive value for appendicitis was 68.7%; however, its negative predictive value for appendicitis was 98.8%.CONCLUSION： The present study suggests that the presence of radiological images of fecal loading in the cecum may be a useful sign of acute appendicitis, and the absence of this sign probably excludes this disease.This is the first description of fecal loading as a radiological sign for acute appendicitis.

Strangulated hernia through a defect of the broad ligament and mobile cecum: A case report

We report a case of 28-year-old woman presenting with small bowel obstruction. She had neither prior surgery nor delivery. An upright abdominal radiograph revealed several air-fluid levels in the small bowel in the midabdomen and the pelvic cavity. Computed tomography demonstrated a dilated small bowel loop in the Douglas＇s fossa, but no definite diagnosis could be made. Supportive therapy with draining the intestinal fluid by a long intestinal tube did not result in improvement, which suggested the possibility of a strangulated hernia. Exploratory laparotomy revealed mobile cecum and a 20-cm length of the ileum herniated into a defect of the right broad ligament. As a gangrenous change was recognized in the incarcerated bowel, its resection was carried out, followed by endto-end anastomosis and closure of the defects of the broad ligament. The postoperative course was uneventful. Intestinal obstruction is a very common cause for presentation to an emergency department, while internal hernia is a rare cause of obstruction. Among internal hernias, those through defects of the broad ligament are extremely rare. Defects of the broad ligament can be either congenital or secondary to surgery, pelvic inflammatory disease, and delivery trauma. In conclusion, we emphasize that hernia of the broad ligament should be added to the list of differential diagnosis for female patients presenting with an intestinal obstruction. Early diagnosis and surgical repair reduce morbidity and mortality from strangulation.

Large cavernous hemangioma in the cecum treated by laparoscopic ileocecal resection

A cavernous hemangioma of the cecum is a rare vascular malformation but is clinically important because of the possibility of massive bleeding.We report a case of a large cavernous hemangioma with pericolic inf iltration in the cecum which was removed successfully using minimally invasive surgery.

Perivascular epithelioid cell tumor of the cecum： a case report and review of literatures

Perivascular epithelioid cell tumors （PEComas） are a group of rare mesenchymal neoplasms which composed of histologically and immunohistochemically distinctive perivascular epithelioid cells （PECs）. In recent years, PEComas have been manily reported in liver, kidney, lung, uterus and adnexa,1 but rare in small or large intestine.2-6 Here, we describe a case of PEComa restricted in the cecal mucosa, which displayed histological characteristics of epithelioid clear cells.

Hepatic cecum:a key integrator of immunity in amphioxus

The vertebrate liver is regarded as an organ essential to the regulation of immunity and inflammation as well as being central to the metabolism of nutrients.Here,we discuss the functions that the hepatic cecum of amphioxus plays in the regulation of immunity and inflammation,and the molecular basis of this.It is apparent that the hepatic cecum performs important roles in the immunity of amphioxus including immune surveillance,clearance of pathogens and acute phase response.Therefore,the hepatic cecum,like the vertebrate liver,is an organ functioning as a key integrator of immunity in amphioxus.

不同粗饲料来源对湖羊羔羊盲肠菌群结构及功能的影响

选用7日龄[(3.77±0.46)kg]湖羊公羔60只,随机分为4个处理组,饲草来源组饲喂苜蓿(Medicago sativa)干草(alfalfa hay,AH)和燕麦(Avenasativa)干草(oat hay,OH),非饲草来源组饲喂甜菜(Betavulgaris)粕(beet pulp,BP)和大豆(Glycine max)皮(soybean hulls,SH)。70日龄时饲养试验结束,各组随机屠宰6只羔羊,获得24个盲肠内容物样品以备16S rDNA测序,研究饲粮粗饲料来源对湖羊羔羊盲肠内容物菌群结构和功能的影响。结果表明:24个盲肠内容物样品共获得72482条有效数据与2999个OTU,物种注释共获得12个门、54个纲、103个目、174个科和349个属;OH组物种数、辛普森指数和香农指数显著高于AH组(P<0.05);盲肠以厚壁菌门和拟杆菌门为核心菌门;瘤胃球菌科为优势菌科;OH组毛螺旋菌科显著高于AH和SH组(P<0.05),克里斯滕森菌科显著高于AH组和BP组(P<0.05);BP组变形菌门显著高于AH、SH和OH组(P<0.05),毛螺旋菌科极显著高于AH和SH组(P<0.01);SH和OH组未鉴定的丹毒丝菌属显著高于AH和BP组。使用Tax4Fun法的预测分析得出湖羔羊盲肠菌群以碳水化合物代谢、脂类、能量和氨基酸代谢为主。相关性分析Muribaculaceae菌科与活体重和日增重之间呈显著正相关关系(P<0.05),普雷沃氏菌科与活体重和日增重之间呈显著负相关关系(P<0.05)。综上所述,开食料不同粗饲料来源由于其纤维素结构不同,对湖羊羔羊盲肠微生物菌群结构及功能作用具有较大差异。

基于微生物和代谢组学研究葡萄籽原花青素对鹅肠道健康的影响

本研究基于微生物和代谢组学方法,探讨饲粮添加葡萄籽原花青素(GSPs)对鹅肠道菌群和代谢物的影响。选择体重相近的35日龄四川白鹅144只,随机分为4组,每组6个重复,每个重复6只。对照组饲喂基础饲粮,3个试验组分别在基础饲粮中添加50、100和150 mg/kg GSPs。预试期7 d,正试期21 d。在63日龄时,每个重复随机选取1只鹅屠宰:取盲肠,测定组织形态指标;取盲肠内容物,测定肠道菌群和代谢物。结果表明:1)与对照组相比,饲粮添加50 mg/kg GSPs显著提高鹅盲肠绒毛高度(P<0.05)。2)与对照组相比,饲粮添加GSPs显著提高鹅盲肠菌群Chao1指数、可观测物种(observed_species)数和PD_whole_tree值(P<0.05),饲粮添加50和100 mg/kg GSPs显著提高盲肠菌群Shannon指数(P<0.05)。在门水平上,与对照组相比,各GSPs添加组盲肠厚壁菌门(Firmicutes)相对丰度提高,盲肠拟杆菌门(Bacteroidota)相对丰度降低;100和150 mg/kg GSPs添加组盲肠变形菌门(Proteobacteria)相对丰度降低。在科水平上,与对照组相比,饲粮添加GSPs提高了盲肠瘤胃球菌科(Ruminococcaceae)、梭菌UCG-014(Clostridia_UCG-014)、毛螺菌科(Lachnospiraceae)和产粪甾醇真细菌群([Eubacterium]_coprostanoligenes_group)的相对丰度,降低了盲肠颤螺菌科(Oscillospiraceae)、理研菌科(Rikenellaceae)和拟杆菌科(Bacteroidaceae)的相对丰度。在属水平上,与对照组相比,饲粮添加GSPs提高了盲肠梭菌UCG-014相对丰度,降低了拟杆菌属(Bacteroides)相对丰度;饲粮添加50和100 mg/kg GSPs提高了盲肠产粪甾醇真细菌群和粪杆菌属(Faecalibacterium)的相对丰度。3)50、100和150 mg/kg GSPs添加组与对照组之间的盲肠差异代谢物数量分别为23、18和36种[变量投影重要性(VIP)>1,P<0.05]。与对照组相比,50、100和150 mg/kg GSPs添加组共有差异代谢物亚精胺表达丰度显著下调(P<0.05)。京都基因与基因组百科全书(KEGG)代谢通路富集分析结果表明,GSPs主要通过β-丙氨酸代谢、精氨酸和脯氨酸代谢以及丙酸盐代谢等途径发挥作用。4)与对照组相比,饲粮添加GSPs显著提高鹅盲肠乙酸和丙酸含量(P<0.05),饲粮添加50和100 mg/kg GSPs显著提高盲肠丁酸含量(P<0.05)。综上所述,饲粮添加GSPs可提高鹅盲肠菌群多样性和丰富度,促进有益菌增殖,通过调节肠道菌群和代谢物改善鹅肠道健康。

3种贵州地方鸡盲肠菌群结构特征的比较

【目的】基于微生物16S rRNA测序技术探究3种贵州地方鸡的盲肠菌群结构特征,鉴别不同品种鸡盲肠富集的特定菌群,从肠道菌群角度解析地方鸡遗传资源特性,进而加深对贵州地方鸡肠道菌群特征的认识。【方法】选取3种贵州地方鸡(乌蒙乌骨鸡11羽、黔东南小香鸡12羽及瑶山鸡12羽),采集盲肠内容物样品检测16SrRNA序列V3~V4可变区,通过QIIME计算鸡盲肠菌群Alpha多样性,以主坐标分析(PCoA)评估鸡盲肠菌群Beta多样性;采用SparCC算法构建盲肠菌群互作网络,使用马修斯相关系数(MCC)算法进行枢纽菌群识别,并以LEfse分析鉴别组间差异的菌群类别及功能通路。【结果】从35羽贵州地方鸡盲肠内容物共测序获得2625245条Clean reads,按序列相似度97%的阈值进行聚类分析共获得727个OTUs。在门分类水平上,3种贵州地方鸡盲肠菌群的优势菌包括拟杆菌门、厚壁菌门、变形菌门、互养菌门和螺旋菌门;在属分类水平上,相对丰度排名前5的属为拟杆菌属、理研菌科_RC9_菌群、考拉杆菌属、普拉梭菌属和脱硫弧菌属。从乌蒙乌骨鸡、黔东南小香鸡和瑶山鸡盲肠菌群中分别获得160、144和149个OTUs用于菌群互作网络研究,对盲肠菌群互作网络结构分析发现网络稳定性排序为瑶山鸡(稳定性指数44.22%)>黔东南小香鸡(稳定性指数41.76%)>是乌蒙乌骨鸡(稳定性指数37.56%),而网络复杂性排序为黔东南小香鸡>乌蒙乌骨鸡>瑶山鸡。颤螺菌属是黔东南小香鸡和瑶山鸡盲肠菌群互作网络中重要性评分最高的枢纽菌群,乳酸杆菌属是黔东南小香鸡盲肠的枢纽菌群,理研菌科_RC9_菌群是乌蒙乌骨鸡盲肠的枢纽菌群。LEfSe分析结果表明,乌蒙乌骨鸡盲肠富集到15个特征OTUs,其功能通路涉及氨基酸生物合成、2-氧羧酸代谢、精氨酸生物合成等;黔东南小香鸡盲肠富集到2个特征OTUs,其功能通路涉及光合作用和链霉素生物合成;瑶山鸡盲肠富集到6个特征OTUs,仅涉及脂多糖生物合成功能通路。【结论】品种是影响贵州地方鸡盲肠菌群组成和结构的重要因素,一些特定微生物存在于不同品种鸡盲肠中。其中,理研菌科_RC9_菌群、瘤胃球菌属、紫单胞菌属等在乌蒙乌骨鸡盲肠中富集;巨单胞菌属、理研菌科_RC9_菌群、考拉杆菌属等在瑶山鸡盲肠中富集;脱硫弧菌属和普拉梭菌属在黔东南小香鸡盲肠中富集。

饲料中添加包膜丁酸钠对蛋雏鸡盲肠原核微生物菌群的影响研究

目的探究在饲料中添加丁酸钠对蛋雏鸡盲肠原核微生物菌群多样性的影响。方法研究选取1日龄罗曼粉蛋鸡,随机分为对照组与试验组,对照组使用标准饲料,试验组饲料中添加1500 mg/kg 30%包膜丁酸钠,其余饲养条件相同。在12、18、24、30日龄时对雏鸡进行称重并记录生长数据;随机选取正常生长的1月龄雏鸡,断头法处死并立即收集盲肠内容物,提取微生物总DNA,利用PCR扩增细菌16S rRNA基因的V3-V4高可变区域并通过Illumina HiSeq测序平台进行高通量测序。结果添加包膜丁酸钠的试验组雏鸡在生长后期的体质量显著增加;α多样性分析表明2组样品间ACE、Chao、Simpson和Shannon指数均未表现出显著差异(p>0.05);在门分类水平上,拟杆菌门(Bacteroidetes)、厚壁菌门(Frimicutes)和变形菌门(Proteobacteria)在盲肠细菌菌群中表现为优势菌群,但在试验组中具有更多的拟杆菌门及更少的厚壁菌门;在属分类水平上,试验组中拟杆菌属(Bacteroides)和乳酸杆菌属(Lactobacillus)的含量显著增加(p<0.05),硫杆菌属(Desulfovibrio)和厌氧螺菌属(Anaerobiospirillum)的含量显著降低(p<0.05)。结论作为新型非抗生素促生长饲料添加剂,包膜丁酸钠并未显著影响雏鸡盲肠原核微生物菌群多样性,但是显著影响了微生物菌属的比例,可改变蛋雏鸡盲肠微生物的组成,有助于改善肠道健康和盲肠菌群。

饲粮添加不同比例黄秋葵秸秆对肉兔生长性能、血液生化指标及盲肠菌群结构的影响

为研究饲粮中添加不同比例黄秋葵秸秆对肉兔生长性能、血液生化指标及盲肠菌群结构的影响,试验选用80只体重相近的断奶肉兔,公母各半,随机分为4组,每组5个重复,每个重复4只兔。对照组饲喂基础饲粮,试验组(4%组、6%组和8%组)分别饲喂含4%、6%、8%黄秋葵秸秆的饲粮,预试期7 d,正式期35 d。结果表明:(1)与对照组相比,饲粮中添加4%、6%、8%的黄秋葵秸秆均可以明显降低断奶肉兔的死亡率,改善断奶肉兔的腹泻情况,其中以4%组效果最好。(2)4%添加组总胆固醇显著低于对照组(P<0.05),其他试验组总胆固醇含量均有降低,但差异不显著(P>0.05);各试验组兔血液中的总胆红素、肌酐、尿素均有不同程度的降低,但差异均不显著(P>0.05);天门冬氨酸氨基转移酶、丙氨酸氨基转移酶均有一定程度的提高,差异不显著(P>0.05)。(3)在Alpha多样性上,Chao1指数,6%添加组显著低于对照组、4%组和8%组(P<0.05),Shannon指数和Simpson指数,各组之间差异均不显著(P>0.05);在门、属水平上,不同黄秋葵秸秆添加量对优势菌属和优势菌门均无显著性影响(P>0.05),但添加8%的黄秋葵秸秆可以提高厚壁菌门、拟杆菌门、瘤胃球菌属、颤螺旋菌属的相对丰度,降低变形菌门的相对丰度。由此可见,肉兔饲粮中添加4%的黄秋葵秸秆对肉兔肝肾功能有一定的调节作用,并可以显著降低肉兔生长过程中的死亡率,添加8%的黄秋葵秸秆可提高一些优势菌群的相对丰度,降低有害菌群的丰度。

不同饲养方式下藏猪盲肠与结肠细菌群落的差异分析

为了探讨不同饲喂方式与不同肠段间藏猪细菌群落组成的差异性,部分阐明藏猪肠道微生物的特异性。选用两年龄的放牧与舍饲藏猪各3头,分别采集盲肠与结肠食糜样品,测定细菌16S rRNA基因的V3-V4区域,分析细菌群落的组成,探讨盲肠与结肠细菌群落的空间差异格局;采用Person相关性分析探索盲肠与结肠细菌群落的相关性。结果表明,不同饲养方式下,在门水平细菌群落分别有4个差异分类单元,在属水平盲肠中有19个差异分类单元、结肠中有9个差异分类单元。不同饲养方式下,藏猪细菌群落的Beta多样性表现出明显的差异性。在放牧养殖条件下,藏猪的盲肠食糜中拟杆菌门、变形菌门和TM7的相对丰度显著高于结肠(P<0.05),厚壁菌门、螺旋体门、放线菌门、软壁菌门与疣微菌门相对丰度两个肠段间无显著差异(P>0.05)。放牧藏猪盲肠中Unclassified_Ruminococcaceae(厚壁菌门、瘤胃球菌科)、Unclassified_Clostridiales(厚壁菌门、梭菌目)、Unclassified_Bacteroidales(拟杆菌门、拟杆菌目)、Turicibacter(厚壁菌门、苏黎世杆菌科)与梭菌属(厚壁菌门、梭菌科)相对丰度显著高于结肠(P<0.05),但链球菌属(厚壁菌门、链球菌科)相对丰度显著低于结肠(P<0.05)。舍饲藏猪盲肠与结肠间细菌群落无显著差异(P>0.05)。放牧藏猪盲肠与结肠中细菌群落关联网络中各节点联系较为紧密,彼此间呈现竞争或者协同作用,舍饲藏猪盲肠与结肠细菌群落关联网络中各节点联系较为松散。结果说明,饲养方式影响藏猪肠道中细菌群落的组成,放牧养殖条件下藏猪肠道细菌表现出更加多元的状态。

短期或长期饲喂高水平豌豆纤维对猪盲肠微生物群落结构和代谢产物的影响

旨在探讨短期或长期饲喂高水平豌豆纤维(Pea fiber,PF)对猪盲肠细菌群落结构和主要代谢产物的影响。选取50头初始体重为(7.2±0.5)kg的28日龄健康断奶杜洛克×长白×大约克仔猪,按体重无差异原则随机分为2组,每组5个圈,每圈5头仔猪。处理组猪按断奶期(试验开始至断奶后30d)、生长期(断奶后30至90d)和育肥期(断奶后90至160d)3个不同生理阶段猪对日粮纤维的耐受量,分别饲喂含10%、20%、30%PF的饲粮。对照组猪饲喂基础饲粮。在第一阶段(仔猪)和试验结束时(育肥猪)屠宰,采集盲肠食糜。以454高通量测序结合real-time PCR方法检测微生物群落结构。气相色谱法检测盲肠食糜中挥发性脂肪酸含量。结果表明:1)日粮中长期或短期饲喂高水平PF对猪ADFI和ADG均无显著影响(P>0.05)。2)长期饲喂PF显著增加猪盲肠中总挥发性脂肪酸含量,显著降低丙酸比例(P<0.05);3)高通量测序分析表明,与对照组相比,短期饲喂PF的仔猪盲肠中Firmicutes门比例下降5.6%,Proteobacteria门比例增加4.3%;长期饲喂PF的肥育猪盲肠中Bacteroidetes门比例增加4.8%,Firmicutes门比例下降6.8%,采食PF后猪盲肠中存在独有优势菌属。4)Real-time PCR结果进一步证实,与对照组相比,短期饲喂PF可显著增加仔猪盲肠中总细菌、Bacteroides-Prevotella-Porphyromonas(BPP)、Enterococcus、Clostridiumcluster IV的拷贝数(P<0.05),极显著增加Bacteroidetes、Lactobacillus和Desulfovibrio desulfuricans数量(P<0.01),极显著降低Firmicutes数量(P<0.01);长期饲喂PF可极显著增加肥育猪盲肠中D.desulfuricans数量(P≤0.01),显著降低总细菌、BPP、Helicobacter-Flexispira-Wollinella(HFW)数量(P<0.05),极显著降低Enterococcus、Streptococcus和Clostridium cluster I数量(P≤0.01)。因此,猪后肠细菌群落(尤其是氢营养菌)可对日粮中高水平的PF做出迅速响应,短链脂肪酸比例的变化暗示这种菌群结构的改变与后肠微生物发酵方式的改变有关。日粮中添加高水平PF虽然可降低盲肠中条件致病菌(如Streptococcus)并提高有益菌(如Lactobacillus)的数量,但很可能不利于盲肠微生物发酵产生丁酸。

葡萄糖氧化酶制剂对肉鸡肠道pH及盲肠微生物的影响

通过探讨葡萄糖氧化酶(Glucose oxidase,GOD)对肉鸡肠道环境的影响,为其在肉鸡生产中的应用提供理论依据。本研究选取300只1日龄罗斯308肉鸡,随机分为5组,每组6个重复,每个重复10只鸡。分别饲喂添加0、0.15%、0.3%、0.4%、0.5%GOD的日粮,研究了其对肉鸡肠道pH及盲肠微生物的影响。结果表明:日粮中添加GOD,不同程度的降低了空肠、回肠pH,但未能显著影响胃和十二指肠pH;GOD具有明显抑制大肠杆菌生长,促进盲肠中乳酸杆菌和双歧杆菌增殖的作用。

桑叶粉和发酵桑叶粉对胡须鸡屠宰性能、肉品质及盲肠菌群的影响

试验旨在研究桑叶粉和发酵桑叶粉对胡须鸡饲养后期屠宰性能、肉品质及盲肠菌群的影响。选用95日龄岭南黄Ⅲ号胡须鸡392只,随机分为7组,即对照组,5%、10%、20%桑叶粉组,5%、10%、20%发酵桑叶粉组。每组4个重复,每个重复14只鸡(7公7母)。预试期4d,正试期28d。结果表明:1与对照组相比,除10%桑叶粉组外,其余各试验组鸡半净膛率显著降低(P<0.05);10%发酵桑叶粉组鸡全净膛率显著降低(P<0.05),20%发酵桑叶粉及10%桑叶粉组鸡全净膛率极显著降低(P<0.01);饲喂5%发酵桑叶粉或20%桑叶粉使胡须鸡腿肌率分别极显著或显著降低(P<0.01;P<0.05)。2与对照组相比,各试验组胸肌剪切力和桑叶粉各组腿肌剪切力值均有所下降,但只有10%桑叶粉组胸肌剪切力值显著下降(P<0.05);20%桑叶粉组腿肌pH45min显著增加(P<0.05);各试验组腿肌b*值均有所降低,其中20%桑叶粉组显著降低(P<0.05)。3与对照组相比,5%、10%桑叶粉组鸡盲肠大肠杆菌数量显著降低(P<0.05),各试验组盲肠乳酸菌与大肠杆菌比值有提高的趋势,但差异不显著(P>0.05)。综合以上试验结果,桑叶粉可在胡须鸡生长后期日粮中添加至10%,发酵桑叶粉可添加至20%。