Influence of Cereal Non-Starch Polysaccharides on Ileo-Caecal and Rectal Microbial Populations in Growing Pigs

The effect of cereal non-starch polysaccharides (NSP) on the gut microbial populations was studied in 5 growing pigs between 39–116 kg body weight according to a Latin square design. The diets were composed to contain different NSP levels. The control diet had a normal NSP content (139 g/kg dry matter (DM)), 2 diets had a low total amount of NSP (95 and 107 g/kg DM) and 2 diets had a high amount of total NSP (191 and 199 g/kg DM). Furthermore, one of the diets within each category had a content of insoluble NSP similar to the control diet and one had a high content of insoluble NSP. Samples were collected from the ileum, via intestinal post valve T-caecum (PVTC) cannulas surgically inserted at the ileo-caecal ostium, and from the rectum. The total microbial flora of the ileal samples were analysed for by defining base pair length with terminal restriction fraction length polymorphism (T-RFLP). The microbial diversity of the coliform flora of the ileal and rectal samples were defined by biochemical fingerprinting. It was observed that many terminal restriction fragments (TRFs) disappeared when new diets were introduced and that some characteristic TRFs were found in the high and low NSP diets, respectively. Both the total gut microflora and the coliform flora were influenced by the dietary NSP content.     

Oxytetracycline-Resistant Coliforms in Commercial Poultry Products

The presence of oxytetracycline-resistant bacteria was investigated with commercially frozen chicken thighs and drumsticks. Bacterial flora were surveyed by means of total and coliform counts with Tryptone Glucose Extract Agar and Desoxycholate Agar, respectively. After counting, the Desoxycholate Agar plates were replicated on the same medium containing 25, 50, 75, and 100 ppm of oxytetracycline. Resistant colonies were found on all samples that were replicated. Of 2613 colonies isolated on Desoxycholate Agar, 47.8% grew in the presence of 25 ppm of oxytetracycline. From 50 to 100 ppm, the number of resistant isolates remained essentially the same, near 34%. Of 812 colonies of antibiotic-resistant bacteria identified with dulcitol-lactose-iron-agar, 82.5% were paracolons, 13.7% were pseudomonads, and 3.8% were Escherichia or Aerobacter. Bacteria resistant to oxytetracycline were shown to be present on commercially processed chicken. The origin of the resistance to oxytetracycline was not established; however, since the antibiotic was not used during processing, it appeared that these antibiotic-resistant bacteria arose in the intestines of the chickens as a result of feed which contained antibiotic. This is supported by a comparison with the antibiotic resistance of coliforms from chickens raised on feed both with and without oxytetracycline, for the percentages of resistant colonies are similar in both commercial chicken and chicken raised on feed containing the antibiotic.     

Gastrointestinal Bacteria of Certain Antarctic Birds and Mammals

An investigation was carried out of the aerobic gram-negative intestinal flora of 158 penguins, 30 skuas, and 66 seals from the Antarctic and sub-Antarctic zones and Phillip Island. Among penguins and seals, 17% and 11%, respectively, were devoid of aerobic enteric organisms, but microscopic examination showed the presence of other bacteria. The coliforms outnumbered the paracolons and nonlactosefermenting bacteria; irregular coliform types and Escherichia coli were predominant. The present study indicated the effect of diet on the composition of the intestinal flora of the birds and mammals examined.     

Microbiological and virological analysis of water from two water filtration plants and their distribution systems

The microbial flora of the water produced by two water filtration plants and their drinking water distribution system were evaluated: the Pont-Viau (PV) and the Repentigny (RE) water filtration plants. Untreated water entering the plants contained 3.6 (PV) and 16.8 most probable number of infectious units (mpniu)/L (RE) enteric viruses and total coliform bacteria counts were 300,000 (PV) and 500,000 cfu/L (RE). Treated water leaving the plant was essentially free of all the bacterial indicators measured (total, stressed, and fecal coliforms; Aeromonas hydrophila; Pseudomonas aeruginosa; Clostridium perfringens; enterococci) as well as of human enteric viruses. Heterotrophic plate counts at 20 and 35 degrees C were low in the freshly treated water leaving the plants, but bacterial regrowth was observed in both distribution systems at all sampling sites. Average counts for the heterotrophic plate count (20 degrees C) were between 10(6) and 10(7) cfu/L and counts were clearly increased with the distance from the plant. The most numerous bacterial genera encountered were Bacillus, Flavobacterium, and Pseudomonas (nonaeruginosa).     

The effect of zinc oxide supplementation on the stability of the intestinal flora with special reference to composition of coliforms in weaned pigs

The effect of a dietary supplementation of zinc oxide (ZnO) on the stability of the intestinal flora and on the composition of coliforms in weaned pigs was investigated. Faecal floras were characterized by their metabolic activities and fermentative capacity (FC) using the Phene Plate generalized microplate. Coliforms were characterized by conventional enumeration and by the Phene Plate-RS plates. The latter measured FC, phenotypic diversity, persistence of each coliform strain in piglets, and similarity among the coliform populations within groups. From weaning onwards, the control pigs (n = 5) were fed a basal diet ad libitum, while experimental pigs (n = 5) were given the same food supplemented with 2500 ppm ZnO. Metabolic fingerprinting of faecal floras indicated marked differences between the composition of floras of treated and control pigs during the first 2 weeks post-weaning. The FC of faecal flora in both groups decreased as pigs aged, but it was significantly (P 相似文献   

几种抗菌药物对腹泻羔羊肠道细菌的影响及临床观察

通过对治疗前后腹泻羔羊粪便细菌检查及临床观察,以查明两种抗菌药物对腹泻羔羊肠道细菌的影响。结果表明,腹泻羔羊治疗前粪便中的革兰氏阳性杆菌,革兰氏阳性球菌及革兰氏阴性杆菌的比例分别为20％、10％和70％。用敌菌净治疗的效果显著,其羔羊肠道细菌的比例接近健康羔羊。用庆大霉素治疗的羔羊,部分出现不良反应,其肠道细菌出现失调状态。     

环境水体中肠道感染菌群与几种典型致病菌的QPCR检测及相关性分析

利用定量PCR(QPCR)方法,对环境水体中的肠道感染菌群及几种致病菌进行4个月的连续检测。结果表明:在污染严重的水体中,埃希氏大肠菌(E.coli)是水中肠道感染菌群的主体,其强度接近于用通用引物检测出的肠道感染菌群强度。当肠道感染菌群拷贝数超过10⁴copies·100 mL^-1时,沙门氏菌(S.typhrmurium)和志贺氏痢疾杆菌(Shigella flexneri)也持续被检出,可以认为是水体病原污染的标志之一;在轻度污染和清洁水体中,当肠道感染菌群拷贝数低于10⁴copies·100 mL^-1时,通过通用引物检测到的肠道感染菌群主要是上述3种病原细菌以外的细菌,且3种病原细菌的出现频度和强度与肠道感染菌群之间没有明显的相关性。     

Examination and characterization of distribution system biofilms.

Investigations concerning the role of distribution system biofilms on water quality were conducted at a drinking water utility in New Jersey. The utility experienced long-term bacteriological problems in the distribution system, while treatment plant effluents were uniformly negative for coliform bacteria. Results of a monitoring program showed increased coliform levels as the water moved from the treatment plant through the distribution system. Increased coliform densities could not be accounted for by growth of the cells in the water column alone. Identification of coliform bacteria showed that species diversity increased as water flowed through the study area. All materials in the distribution system had high densities of heterotrophic plate count bacteria, while high levels of coliforms were detected only in iron tubercles. Coliform bacteria with the same biochemical profile were found both in distribution system biofilms and in the water column. Assimilable organic carbon determinations showed that carbon levels declined as water flowed through the study area. Maintenance of a 1.0-mg/liter free chlorine residual was insufficient to control coliform occurrences. Flushing and pigging the study area was not an effective control for coliform occurrences in that section. Because coliform bacteria growing in distribution system biofilms may mask the presence of indicator organisms resulting from a true breakdown of treatment barriers, the report recommends that efforts continue to find methods to control growth of coliform bacteria in pipeline biofilms.     

Examination and characterization of distribution system biofilms

Investigations concerning the role of distribution system biofilms on water quality were conducted at a drinking water utility in New Jersey. The utility experienced long-term bacteriological problems in the distribution system, while treatment plant effluents were uniformly negative for coliform bacteria. Results of a monitoring program showed increased coliform levels as the water moved from the treatment plant through the distribution system. Increased coliform densities could not be accounted for by growth of the cells in the water column alone. Identification of coliform bacteria showed that species diversity increased as water flowed through the study area. All materials in the distribution system had high densities of heterotrophic plate count bacteria, while high levels of coliforms were detected only in iron tubercles. Coliform bacteria with the same biochemical profile were found both in distribution system biofilms and in the water column. Assimilable organic carbon determinations showed that carbon levels declined as water flowed through the study area. Maintenance of a 1.0-mg/liter free chlorine residual was insufficient to control coliform occurrences. Flushing and pigging the study area was not an effective control for coliform occurrences in that section. Because coliform bacteria growing in distribution system biofilms may mask the presence of indicator organisms resulting from a true breakdown of treatment barriers, the report recommends that efforts continue to find methods to control growth of coliform bacteria in pipeline biofilms.     

Biochemical fingerprinting of water coliform bacteria, a new method for measuring phenotypic diversity and for comparing different bacterial populations.

A simple, automated microplate system for biochemical characterization of water isolates can be used to obtain fingerprints of the bacterial flora from various water samples. Mathematical models for calculating the diversities and similarities between bacterial populations are described for such fingerprints. The diversity may give information on whether an indigenous or allochthonous flora is present, and the similarities between bacterial populations, as calculated by using a population similarity coefficient (Sp), may indicate contaminations between different water samples. The system was demonstrated on coliform bacterial populations from various water samples, with or without suspected intercontamination. For unrelated water samples, the Sps were close to 0, whereas repeated samples of the same source showed Sps of 0.64 to 0.74. The Sp values from several water samples were also clustered to form a dendrogram, thus indicating the relative similarities between the bacterial populations to confirm suspected common sources of pollution.     

Mathematical model of plasmid-mediated resistance to ceftiofur in commensal enteric Escherichia coli of cattle

Antimicrobial use in food animals may contribute to antimicrobial resistance in bacteria of animals and humans. Commensal bacteria of animal intestine may serve as a reservoir of resistance-genes. To understand the dynamics of plasmid-mediated resistance to cephalosporin ceftiofur in enteric commensals of cattle, we developed a deterministic mathematical model of the dynamics of ceftiofur-sensitive and resistant commensal enteric Escherichia coli (E. coli) in the absence of and during parenteral therapy with ceftiofur. The most common treatment scenarios including those using a sustained-release drug formulation were simulated; the model outputs were in agreement with the available experimental data. The model indicated that a low but stable fraction of resistant enteric E. coli could persist in the absence of immediate ceftiofur pressure, being sustained by horizontal and vertical transfers of plasmids carrying resistance-genes, and ingestion of resistant E. coli. During parenteral therapy with ceftiofur, resistant enteric E. coli expanded in absolute number and relative frequency. This expansion was most influenced by parameters of antimicrobial action of ceftiofur against E. coli. After treatment (>5 weeks from start of therapy) the fraction of ceftiofur-resistant cells among enteric E. coli, similar to that in the absence of treatment, was most influenced by the parameters of ecology of enteric E. coli, such as the frequency of transfer of plasmids carrying resistance-genes, the rate of replacement of enteric E. coli by ingested E. coli, and the frequency of ceftiofur resistance in the latter.     

Biochemical fingerprinting of water coliform bacteria, a new method for measuring phenotypic diversity and for comparing different bacterial populations.

A simple, automated microplate system for biochemical characterization of water isolates can be used to obtain fingerprints of the bacterial flora from various water samples. Mathematical models for calculating the diversities and similarities between bacterial populations are described for such fingerprints. The diversity may give information on whether an indigenous or allochthonous flora is present, and the similarities between bacterial populations, as calculated by using a population similarity coefficient (Sp), may indicate contaminations between different water samples. The system was demonstrated on coliform bacterial populations from various water samples, with or without suspected intercontamination. For unrelated water samples, the Sps were close to 0, whereas repeated samples of the same source showed Sps of 0.64 to 0.74. The Sp values from several water samples were also clustered to form a dendrogram, thus indicating the relative similarities between the bacterial populations to confirm suspected common sources of pollution.     

双歧杆菌的生物拮抗与药敏试验

本文介绍了双歧杆菌生物拮抗试验和药物敏感试验的方法。结果说明双歧杆菌对肠道正常菌群及病原菌有调节与拮抗作用,且对多种抗生素敏感。提示在治疗肠道感染时,应尽量避免口服对双歧杆菌敏感的药物,否则会使肠道感染加重或蔓延。     

Enriched collagen as coadjuvant therapeutic agent in experimental osteomyelitis in dogs

Osteomyelitis was induced in the tibiae of dogs by injecting hemolytic strain of Staphylococcus aureus. Clinical, radiological and histomorphological reactions in the diseased tibiae were studied up to 15 weeks to evaluate the response of infected bone to parenteral oxytetracycline in cases of closed wounds and surgical curettage, antimicrobial irrigation along with parenteral oxytetracycline therapy in animals carrying open wounds. Enriched collagen as a constituent of therapeutic regimen was also administered locally and its efficacy during resolution of osteomyelitis was compared with other treatments. Surgical curettage along with irrigation of lesions was observed to be an effective method for bringing an early recovery in aggravated cases of osteomyelitis. The addition of collagen enhanced the healing process in comparison with non-collagen treated animals.     

Characterization of the coliform and enteric bacilli in the environment of calves with colibacillosis

In the first part of the present study the coliform and enteric bacilli in the environment of calves with colibacillosis were examined. The occurrence, number, and pathogenic properties of Escherichia coli in barnyard soils were obtained from six cattle ranches. The O and K serogroups of E. coli isolates obtained from the feces of calves with colibacillosis born at these cattle ranches were determined, and their serotypes were compared with the E. coli O and K serotypes found in soils. The results showed a reservoir of potentially pathogenic E. coli in barnyard soils contaminated with bovine feces. For the second part of this study, 6 healthy calves and 51 calves with colibacillosis were studied. The numbers of total aerobic heterotrophic bacteria, total streptococci, fecal streptococci, total coliforms, and fecal coliforms in the feces of calves were determined. In addition, coliform and enteric bacilli from the feces of both healthy and diseased calves were identified, and their indole, methyl red, Voges-Proskauer, citrate (IMViC) types were described. In parallel, the IMViC types of coliform and enteric bacilli isolated from barnyard soils previously contaminated with bovine feces were compared with those isolated from uncontaminated soils. All fecal specimens were also examined for the presence of rotavirus. No significant effect on the numbers of the bacterial types was found. The results suggest that the predominant IMViC types found in the feces of calves with colibacillosis originate from the soil. From this study it is apparent that the occurrence, number, and survival of E. coli in barnyard soils is related to ranch husbandry and sanitary practices.     

Characterization of the coliform and enteric bacilli in the environment of calves with colibacillosis.

In the first part of the present study the coliform and enteric bacilli in the environment of calves with colibacillosis were examined. The occurrence, number, and pathogenic properties of Escherichia coli in barnyard soils were obtained from six cattle ranches. The O and K serogroups of E. coli isolates obtained from the feces of calves with colibacillosis born at these cattle ranches were determined, and their serotypes were compared with the E. coli O and K serotypes found in soils. The results showed a reservoir of potentially pathogenic E. coli in barnyard soils contaminated with bovine feces. For the second part of this study, 6 healthy calves and 51 calves with colibacillosis were studied. The numbers of total aerobic heterotrophic bacteria, total streptococci, fecal streptococci, total coliforms, and fecal coliforms in the feces of calves were determined. In addition, coliform and enteric bacilli from the feces of both healthy and diseased calves were identified, and their indole, methyl red, Voges-Proskauer, citrate (IMViC) types were described. In parallel, the IMViC types of coliform and enteric bacilli isolated from barnyard soils previously contaminated with bovine feces were compared with those isolated from uncontaminated soils. All fecal specimens were also examined for the presence of rotavirus. No significant effect on the numbers of the bacterial types was found. The results suggest that the predominant IMViC types found in the feces of calves with colibacillosis originate from the soil. From this study it is apparent that the occurrence, number, and survival of E. coli in barnyard soils is related to ranch husbandry and sanitary practices.     

Metagenomic analysis of the viral flora of pine marten and European badger feces

A thorough understanding of the diversity of viruses in wildlife provides epidemiological baseline information about potential pathogens. Metagenomic analysis of the enteric viral flora revealed a new anellovirus and bocavirus species in pine martens and a new circovirus-like virus and geminivirus-related DNA virus in European badgers. In addition, sequences with homology to viruses from the families Paramyxo- and Picornaviridae were detected.     

Growth of Escherichia coli in a pulp and cardboard mill

The coliform flora of a pulp and cardboard mill that uses birch as the raw material and ammonium sulphate as the process chemical was studied. Escherichia coli was observed to multiply in the mill. It persisted as the dominant thermotolerant coliform in the effluent. Klebsiellae were encountered among total coliforms only. The E. coli strains isolated had the biochemical characteristics and maximum growth temperatures typical to the species. However, serotyping and hemolysin test differentiated these strains from pathogenic and fecal E. coli.     

阿如拉-7味散对肠道菌群失调小鼠免疫功能及肠道菌群多样性的影响

目的研究阿如拉-7味散对抗生素诱导肠道菌群失调小鼠的免疫功能和肠道菌群多样性的影响。方法选取50只清洁级昆明小鼠,分为正常对照组、自然恢复组、阳性对照组、阿如拉-7味散低剂量组(0.5 g/mL)和阿如拉-7味散高剂量组(1.0 g/mL)。将所有小鼠用头孢曲松钠和盐酸林可霉素混合药液灌胃制备肠道菌群失调模型,第8天起各组小鼠相应药物连续治疗7 d,实验结束时进行样品采集。采集血清和回肠组织,采用ELISA法检测血清中的IgG、IFN-γ和TNF-α含量以及回肠组织中的sIgA含量;采集盲肠内容物,采用高通量测序技术检测肠道菌群多样性;采集胸腺和脾脏,测定免疫器官指数。结果阿如拉-7味散低、高剂量可显著提高抗生素诱导肠道菌群失调小鼠的脾脏指数(P<0.01)、血清IFN-γ(P<0.05)和TNF-α(P<0.01)含量以及回肠黏膜sIgA含量(P<0.01),但对胸腺指数(P>0.05)和血清IgG含量(P>0.05)无显著影响。各用药组与自然恢复组相比,尤其阿如拉-7味散低剂量组,小鼠肠道菌群丰富度和多样性明显升高。结论阿如拉-7味散对抗生素诱导肠道菌群失调小鼠具有提高免疫器官指数、增强肠道免疫功能和改善肠道菌群的作用。     

The effects of selected antimicrobials on glucose transport in the rat intestine.

To determine whether oxytetracycline hydrochloride and the sodium salt of ampicillin have any adverse effects on the rat intestine, enteric enzyme levels and glucose transport rates were measured in vitro in rats. The intestinal transport of glucose did not differ significantly between control animals and those pretreated with ampicillin. For animals pretreated with oxytetracycline, the transport rates were significantly lower than those for the control group. The difference between the ampicillin and oxytetracycline groups, however, was not statistically significant. No significant differences in enteric levels of sucrase and maltase activity were found between any of the groups. The possibility that some antimicrobial agents may interfere with the absorption of nutrients suggested the need for caution in using these drugs in experimental animals.