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a prospective case-control and molecular epidemiological study of human cases of shiga toxin-producing escherichia coli in new zealand.shiga toxin-producing escherichia coli (stec) o157:h7 and related non-o157 stec strains are enteric pathogens of public health concern worldwide, causing life-threatening diseases. cattle are considered the principal hosts and have been shown to be a source of infection for both foodborne and environmental outbreaks in humans. the aims of this study were to investigate risk factors associated with sporadic stec infections in humans in new zealand and to provide epidemiological information about ...201324079470
short communication: antimicrobial efficacy of intramammary treatment with a novel biphenomycin compound against staphylococcus aureus, streptococcus uberis, and escherichia coli-induced mouse mastitis.bovine mastitis undermines udder health, jeopardizes milk production, and entails prohibitive costs, estimated at $2 billion per year in the dairy industry of the united states. despite intensive research, the dairy industry has not managed to eradicate the 3 major bovine mastitis-inducing pathogens: staphylococcus aureus, streptococcus uberis, and escherichia coli. in this study, the antimicrobial efficacy of a newly formulated biphenomycin compound (aic102827) was assessed against intramammary ...201324054294
the phenotypic and genotypic characteristics of antibiotic resistance in escherichia coli populations isolated from farm animals with different exposure to antimicrobial agents.the aim of the study was to determine the influence of the presence or the absence of antibiotic input on the emergence and maintenance of resistance in commensal bacteria from food producing animals. the research material constituted e. coli isolates from two animal species: swine at different age from one conventional pig farm with antibiotic input in young pigs and from beef and dairy cattle originated from organic breeding farm. the sensitivity to 16 antimicrobial agents was tested, and the ...201324053020
susceptibility to antimicrobial agents among bovine mastitis pathogens isolated from north american dairy cattle, 2002-2010.approximately 8,000 isolates of streptococcus agalactiae, streptococcus dysgalactiae, streptococcus uberis, staphylococcus aureus, and escherichia coli, isolated by 25 veterinary laboratories across north america between 2002 and 2010, were tested for in vitro susceptibility to beta-lactam, macrolide, and lincosamide drugs. the minimal inhibitory concentrations (mics) of the beta-lactam drugs remained low against most of the gram-positive strains tested, and no substantial changes in the mic dis ...201323907894
differential response of bovine mammary epithelial cells to staphylococcus aureus or escherichia coli agonists of the innate immune system.mastitis caused by escherichia coli and staphylococcus aureus is a major pathology of dairy cows. to better understand the differential response of the mammary gland to these two pathogens, we stimulated bovine mammary epithelial cells (bmec) with either e. coli crude lipopolysaccharide (lps) or with s. aureus culture supernatant (sas) to compare the transcriptomic profiles of the initial bmec response. by using hek 293 reporter cells for pattern recognition receptors, the lps preparation was fo ...201323758654
prevalence of mastitis in dairy cows from smallholder farms in zimbabwe.a cross-sectional study was conducted to determine the prevalence of sub-clinical and clinical mastitis and the associated factors in cows from selected smallholder dairy farms in zimbabwe. physical examinations were conducted on all lactating cows for evidence of signs of clinical mastitis. composite milk samples were collected from all lactating cows for bacterial culture and somatic cell counting. cows were categorised as clinical if they exhibited clinical features of mastitis, or sub-clinic ...201323718150
biotransformation of l-ornithine from l-arginine using whole-cell recombinant arginase.a recombinant arginase was generated for a whole-cell biotransformation system to convert l-arginine to l-ornithine in escherichia coli. the gene arg1 coding arginase from bos taurus liver was synthesized and expressed in e. coli bl21 (de3) via petduet-1. the recombinant arginase was used to catalyze l-arginine to l-ornithine and urea. the reaction was optimal at ph 9.5 and 37 °c. manganese (10(-5 )m) and emulsifier op-10 [0.033 % (v/v)] could promote arginase activity. in a scale up study, l-ar ...201323700128
prednisolone and cefapirin act synergistically in resolving experimental escherichia coli mastitis.mastitis in dairy cows is typically treated with intramammary antibiotics. the combination of antibiotics with corticosteroids tends to have a large market share where these products are registered. our objective was to investigate the effect of prednisolone in combination with cefapirin on the inflammatory response of experimentally induced escherichia coli mastitis. six midlactating holstein-friesian cows were challenged in 3 quarters with e. coli and treated at 4, 12, 24, and 36 h postinfecti ...201323684040
comparison of the prevalence of shiga toxin-producing escherichia coli strains o157 and o26 between beef and dairy cattle in japan.with the aim of comparing the prevalence of shiga toxin-producing escherichia coli (stec) o157 and o26 between beef and dairy cattle, we collected rectal content samples from 250 beef cattle on 25 beef farms and 250 dairy cows on 25 dairy farms from july through september 2011. stec o157 was isolated from 16 beef cattle on 7 beef farms, while no stec o157 was isolated from any dairy farms. this result suggests that the prevalence of stec o157 is higher in beef cattle than in dairy cattle. stec o ...201323595164
a polyclonal antibody against recombinant bovine haptoglobin expressed in escherichia coli.the nucleotide sequence of the predicted immunodominant region of bovine haptoglobin (pirbohp), without the signal peptide sequence, was synthesized based on the codon usage bias of escherichia coli. the synthesized pirbohp gene was cloned into the prokaryotic expression vector pet-32a (+), which contains a his-tag. the recombinant pirbohp protein was successfully expressed in e. coli bl21 (de3) cells. western blot analysis showed that the purified recombinant pirbohp protein could be recognized ...201324328747
the effect of meloxicam on pain sensitivity, rumination time, and clinical signs in dairy cows with endotoxin-induced clinical mastitis.the objectives of this study were to (1) evaluate the use of a pressure algometer and an automated rumination monitoring system to assess changes in pain sensitivity and rumination time in response to endotoxin-induced clinical mastitis and (2) evaluate the effect of the nonsteroidal antiinflammatory drug meloxicam on pain sensitivity and rumination time, as well as other clinical signs, in dairy cattle with endotoxin-induced clinical mastitis. clinical mastitis was induced in 12 primiparous and ...201323522672
noninferiority trial comparing a first-generation cephalosporin with a third-generation cephalosporin in the treatment of nonsevere clinical mastitis in dairy cows.the objective of this study was to evaluate the noninferiority of 2 intramammary treatments for nonsevere clinical mastitis. the 2 treatments were a first-generation cephalosporin (cephapirin sodium, 2 treatments 12h apart) and a third-generation cephalosporin (ceftiofur hydrochloride, treatments once a day for 5d). a total of 296 cases on 7 farms met the enrollment criteria for the study. streptococcus dysgalactiae was the most common bacterial species identified in milk samples from cows with ...201323958017
naturally occurring mastitis disrupts developmental competence of bovine oocytes.we examined the effects of naturally occurring mastitis on bovine oocyte developmental competence in vitro. specifically, we investigated the effects of intramammary infection on the ovarian pool of oocytes (i.e., follicle-enclosed oocytes) and their ability to undergo in vitro maturation, fertilization, and further development to the blastocyst stage. culled holstein cows (n=50) from 9 commercial dairy farms in israel were allotted to 3 groups according to somatic cell count (scc) records of th ...201323957998
faecal occurrence and emissions of livestock-associated methicillin-resistant staphylococcus aureus (lamrsa) and esbl/ampc-producing e. coli from animal farms in germany.the occurrence of lamrsa (livestock-associated methicillin-resistant staphylococcus aureus) and extended-spectrum beta-lactamase (esbl) and/or plasmid-mediated ampc beta-lactamase-producing (ampc) enterobacteriaceae in healthy livestock herds is known for some time.the spread of these bacteria in the environment is discussed critically.the object of this study was to determine the presence of these microorganisms in faeces of livestock as well as the discussion about a potential faecal emission. ...201323540202
real-time evaluation of milk quality as reflected by clotting parameters of individual cow's milk during the milking session, between day-to-day and during lactation.real-time analysis of milk coagulation properties as performed by the afilab™ milk spectrometer introduces new opportunities for the dairy industry. the study evaluated the performance of the afilab™ in a milking parlor of a commercial farm to provide real-time analysis of milk-clotting parameters -afi-cf for cheese manufacture and determine its repeatability in time for individual cows. the afilab™ in a parlor, equipped with two parallel milk lines, enables to divert the milk on-line into two b ...201323537499
short communication: experimentally induced mastitis reduces weight shifting between the rear legs while standing in dairy cows.the objectives of this study were to evaluate changes in weight shifting between legs while standing on a weighing platform in response to endotoxin-induced clinical mastitis, and to evaluate the effect of the nonsteroidal antiinflammatory drug flunixin meglumine on weight distribution between legs while standing in dairy cattle with endotoxin-induced clinical mastitis. clinical mastitis was induced in 10 primiparous and 9 multiparous lactating dairy cows (days in milk=55 ± 12; mean ± standard d ...201323497993
characterization of shiga toxin-producing escherichia coli o130:h11 and o178:h19 isolated from dairy cows.shiga toxin-producing e. coli (stec) are isolated from human patients with bloody diarrhea, hemorrhagic colitis (hc), and hemolytic uremic syndrome (hus). in the last years, the infections with non-o157 serotypes are increasing their frequency of association with human disease. stec produce shiga toxin (stx) and other virulence factors that could contribute to human pathogenesis. cattle are the main reservoir and the transmission to humans is through the consumption of undercooked meat, non-past ...201323483233
the association between bedding material and the bacterial counts of staphylococcus aureus, streptococcus uberis and coliform bacteria on teat skin and in teat canals in lactating dairy cattle.several mastitis-causing pathogens are able to colonize the bovine teat canal. the objective of this study was to investigate the association between the treatment of sawdust bedding with a commercial alkaline conditioner and the bacterial counts on teat skin and in the teat canal. the study used a crossover design. ten lactating holstein cows that were free of udder infections and mastitis were included in the study. the animals were bedded on either untreated sawdust or sawdust that had been t ...201323445624
effects of bos taurus autosome 9-located quantitative trait loci haplotypes on the disease phenotypes of dairy cows with experimentally induced escherichia coli mastitis.several quantitative trait loci (qtl) affecting mastitis incidence and mastitis-related traits such as somatic cell score exist in dairy cows. previously, qtl haplotypes associated with susceptibility to escherichia coli mastitis in nordic holstein-friesian (hf) cows were identified on bos taurus autosome 9. in the present study, we induced experimental e. coli mastitis in danish hf cows to investigate the effect of 2 e. coli mastitis-associated qtl haplotypes on the cows' disease phenotypes and ...201323357017
the effect of supportive e. coli mastitis treatment on pmn chemiluminescence and subpopulations of t lymphocytes.the aim of this field study was to assess the impact of a single i.m. injection of lysozyme dimer and flunixin meglumine in combination with intramammary and systemic antibiotic on chemiluminescence of pmn (polymorphonuclear leucocytes) and subpopulations of lymphocyte t in blood of cows with e. coli mastitis. examinations were performed on 30 dairy cows affected with naturally occurring acute form of e. coli mastitis. cows were randomly divided into three groups according to the method of treat ...201324597301
determination of ceftiofur derivatives in serum, endometrial tissue, and lochia in puerperal dairy cows with fever or acute puerperal metritis after subcutaneous administration of ceftiofur crystalline free acid.acute puerperal metritis (apm) is one of the most common diseases during the puerperal period. systemic administration of ceftiofur for 5 consecutive days has been shown to be effective for treatment of apm. the objective of this study was to determine concentrations of ceftiofur derivatives in serum, endometrial tissue, and lochia of cows with fever postpartum or apm 4 to 6d after treatment with a single subcutaneous dose of 6.6 mg of ceftiofur crystalline free acid (ccfa)/kg of estimated bw at ...201323261383
evaluation of an alternative dosing regimen of a j-5 mastitis vaccine against intramammary escherichia coli challenge in nonlactating late-gestation dairy cows.the objective of the study was to evaluate the efficacy of an alternative vaccination regimen of a j-5 bacterin against intramammary escherichia coli challenge in nonlactating late-gestation dairy cows. the parameters analyzed to assess the effect of vaccination were milk yield, milk conductivity, somatic cell count, j-5-specific serum igg titers, and clinical signs. twenty multiparous holstein cows from the cornell teaching and research dairy herd were paired by days in milk and were randomly s ...201323726420
relationship between concentration of lingual antimicrobial peptide and somatic cell count in milk of dairy cows.lingual antimicrobial peptide (lap) belongs to the β-defensin family in cattle and is found in milk. lap concentrations increase in milk from mastitic udders; however, the relationship between lap concentrations and the somatic cell count (scc) in milk remains to be elucidated in detail. therefore, the present study was undertaken to investigate the relationship between lap concentrations and the scc in bovine milk to assess whether lap may be used as an indicator of scc. milk was collected from ...201323528609
detection of new delhi metallo-beta-lactamase and extended-spectrum beta-lactamase genes in escherichia coli isolated from mastitic milk samples.in this study, eight escherichia coli isolates were obtained from milk samples of dairy cattle suffering from clinical/subclinical mastitis. isolates were characterized for antimicrobial resistance traits and virulence genes. results revealed that one isolate was harbouring new delhi metallo-beta-lactamase gene (blandm ). cloning and sequencing of the pcr amplicon confirmed the identity of the gene (genbank accession no. kc769583) having 100% homology with blandm-5 (genbank accession no. jn10459 ...201323870003
the effect of repeated episodes of bacteria-specific clinical mastitis on mortality and culling in holstein dairy cows.the objective of this study was to estimate the effect of a first and repeated cases of bacteria-specific clinical mastitis (cm) on the risk of mortality and culling in holstein dairy cows. the pathogens studied were streptococcus spp., staphylococcus aureus, staphylococcus spp., escherichia coli, klebsiella spp., trueperella pyogenes, others, and no growth on aerobic culture. a total of 50,166 lactations were analyzed from 5 large, high-milk-producing dairy herds in new york state from 2003/200 ...201323769361
cost-effectiveness of farm interventions for reducing the prevalence of vtec o157 on uk dairy farms.a randomized control trial on verocytotoxigenic escherichia coli (vtec)-infected farms found evidence that: (1) keeping animals in the same group; (2) maintaining dry bedding; (3) preventing direct contact with neighbouring cattle; and (4) maintaining a closed herd, were associated with a reduced risk of infection in youngstock aged 3–18 months. this study evaluated these interventions using a cost-effectiveness framework for uk dairy farms. keeping animals in the same group was considered to ha ...201323149259
effects of induced energy deficiency on lactoferrin concentration in milk and the lactoferrin reaction of primary bovine mammary epithelial cells in vitro.a dietary energy restriction to 49% of total energy requirements was conducted with red holstein cows for three weeks in mid-lactation. at the last day of the restriction phase, primary bovine mammary epithelial cells (pbmec) of eight restriction (rf) and seven control-fed (cf) cows were extracted out of one litre of milk and cultured. in their third passage, an immune challenge with the most prevalent, heat-inactivated mastitis pathogens escherichia coli (e. coli) and staphylococcus aureus (s. ...201322540894
environmental sampling for evaluating verotoxigenic escherichia coli o157: h7 status in dairy cattle herds.verotoxigenic escherichia coli o157:h7 is a zoonotic bacterial pathogen capable of causing severe disease in human beings. cattle are considered to be the main reservoir of the bacterium. the objective of the current study was to compare environmental sampling (consisting of dust, overshoe, and pooled pat samples) with pooled, individual fecal sampling for determining the cattle herd status under field conditions in naturally infected dairy herds. thirty-one dairy cattle farms in sweden, where v ...201323404479
association of wild bird density and farm management factors with the prevalence of e. coli o157 in dairy herds in ohio (2007-2009).our objective was to determine the role that european starlings (sturnus vulgaris) play in the epidemiology of escherichia coli o157:h7 in dairy cattle. we visited 150 dairy farms in ohio twice during summer and fall months from 2007 to 2009. fresh faecal pats from 30 lactating cows were collected during each visit. information on farm management and environmental variables was gathered through a questionnaire administered to the farm owner. the number of starlings observed on the farm was also ...201222333436
influence of vitamin d on fecal shedding of escherichia coli o157:h7 in naturally colonized cattle.three experiments were conducted to evaluate the influence of vitamin d on fecal shedding of escherichia coli o157:h7 in cattle. in the first experiment, two groups of cattle (beef and dairy) were assigned to a control treatment or to receive 0.5 × 10(6) iu vitamin d per day via oral bolus for 10 days. fecal samples were collected before and throughout the dosing period for culture of e. coli o157:h7. no differences were observed for fecal shedding of e. coli o157:h7 among treatments for either ...201222289592
methodologies for screening of bacteria-carbohydrate interactions: anti-adhesive milk oligosaccharides as a case study.many studies have demonstrated the capacity of glycan-based compounds to disrupt microbial binding to mucosal epithelia. therefore, oligosaccharides have potential application in the prevention of certain bacterial diseases. however, current screening methods for the identification of anti-adhesive oligosaccharides have limitations: they are time-consuming and require large amounts of oligosaccharides. there is a need to develop analytical techniques which can quickly screen for, and structurall ...201222507447
evaluation of cytokine expression by blood monocytes of lactating holstein cows with or without postpartum uterine disease.whereas neutrophils are the main phagocytic leukocytes, monocytes and macrophages are actively involved in immunomodulation after infection. recent studies have demonstrated that neutrophil function is impaired by the state of negative energy balance around parturition, and that cows that develop uterine disease have a greater degree of negative energy balance than healthy cows. the objectives of this study were to compare monocyte gene expression and protein secretion of selected cytokines from ...201221924475
cloning and identification of novel hydrolase genes from a dairy cow rumen metagenomic library and characterization of a cellulase gene.interest in cellulose degrading enzymes has increased in recent years due to the expansion of the ellulosic biofuel industry. the rumen is a highly adapted environment for the degradation of cellulose and a promising source of enzymes for industrial use. to identify cellulase enzymes that may be of such use we have undertaken a functional metagenomic screen to identify cellulase enzymes from the bacterial community in the rumen of a grass-hay fed dairy cow.201223062472
proteolytic and proteomic changes in milk at quarter level following infusion with escherichia coli lipopolysaccharide.mastitis is a major disease in dairy cattle, which causes significant economic losses due to decreased milk production, veterinary costs, and discarded milk. escherichia coli is one of the most prevalent species of gram-negative bacteria that induce clinical mastitis. the objective of the present study was to characterize the proteolytic and proteomic changes in milk in response to infusion with lipopolysaccharide (lps) at quarter level in a model mastitis system. one quarter of each of 2 cows w ...201222459814
sickness behavior in dairy cows during escherichia coli mastitis.the consequences of mastitis in terms of dairy cow behavior are relatively unknown. future assessment of dairy cow welfare during mastitis will be facilitated by knowledge about the potential of mastitis to induce sickness behavior. our aim was to examine behavior of dairy cows in the period from 2 d before (d -2 and -1) to 3 d (d 0, 1, and 2) after experimental intramammary challenge with escherichia coli. effects of experimentally induced mastitis on behavior were examined in 20 primiparous da ...201222281328
influence of environmental temperature on the physiological, endocrine, and immune responses in livestock exposed to a provocative immune challenge.although livestock experience many stressors throughout their life, one of the most commonly experienced, and most difficult to control, is stress caused by fluctuations in environmental temperatures that extend beyond the thermoneutral (tn) zone for an animal. in swine, cold stress has long been recognized as a main cause of neonatal morbidity and mortality. a possible explanation for this increased morbidity and mortality may be related to their inability to generate a febrile response. previo ...201222425434
short communication: the effects of experimentally induced escherichia coli clinical mastitis on lying behavior of dairy cows.clinical mastitis is a commonly occurring and economically important problem in the dairy industry. researchers have suggested that changes in lying behavior could be useful as early indicators of cow discomfort and poor welfare. the objective of this study was to determine the associations between the onset of illness resulting from experimentally induced clinical mastitis and measures of lying behavior. clinical mastitis was induced in 21 lactating dairy cows (parity=2.0±1.0, range=1 to 4; day ...201222541485
a two reservoir model to predict escherichia coli losses to water from pastures grazed by dairy cows.animal agriculture has been identified as an important source of diffuse faecal microbial pollution of water. our current understanding of the losses of faecal microbes from grazed pasture systems is however poor. to help synthesise our current knowledge, a simple two reservoir model was constructed to represent the faecal and environmental sources of escherichia coli found in a grazed pastoral system. the size of the faecal reservoir was modelled on a daily basis with inputs from grazing animal ...201222280922
a protease-insensitive feruloyl esterase from china holstein cow rumen metagenomic library: expression, characterization, and utilization in ferulic acid release from wheat straw.a metagenomic library of china holstein cow rumen microbes was constructed and screened for novel gene cluster. a novel feruloyl esterase (fae) gene was identified with a length of 789 bp and encoded a protein displaying 56% identity to known esterase sequences. the gene was functionally expressed in escherichia coli bl21 (de3), and the total molecular weight of the recombined protein was 32.4 kda. the purified enzyme showed a broad specificity against the four methyl esters of hydroxycinnamic a ...201222352374
repertoire of escherichia coli agonists sensed by innate immunity receptors of the bovine udder and mammary epithelial cells.escherichia coli is a frequent cause of clinical mastitis in dairy cows. it has been shown that a prompt response of the mammary gland after e. coli entry into the lumen of the gland is required to control the infection, which means that the early detection of bacteria is of prime importance. yet, apart from lipopolysaccharide (lps), little is known of the bacterial components which are detected by the mammary innate immune system. we investigated the repertoire of potential bacterial agonists s ...201222330199
effect of intrauterine dextrose or antibiotic therapy on reproductive performance of lactating dairy cows diagnosed with clinical endometritis.the objectives of this study were to assess the responses to treatments (clinical cure and cow survival 14 d posttherapy) of cows with clinical endometritis (ce) that received intrauterine infusion of a hypertonic solution of 50% dextrose (dex) or subcutaneous ceftiofur crystalline free acid (ccfa) and subsequent pregnancy per artificial insemination (p/ai) in cows with ce compared with cows without ce. cows (n=760) from 2 dairy herds were screened for ce using vaginoscopy and measurement of cer ...201222459836
the association between teat end hyperkeratosis and teat canal microbial load in lactating dairy cattle.most pathogens that cause bovine mastitis invade the udder lumen through the teat canal. amino acids and intercellular lipids may support microbial colonisation of the teat canal epithelium by pathogenic microorganisms. the aim of this study was to investigate the association between teat end hyperkeratosis, which is induced by machine milking, and teat canal microbial load. contralateral teats, which differed in teat end hyperkeratosis scores, were identified in a split-udder experiment. the te ...201222445537
protective effect of recombinant staphylococcal enterotoxin a entrapped in polylactic-co-glycolic acid microspheres against staphylococcus aureus infection.staphylococcus aureus is an important cause of nosocomial and community-acquired infections in humans and animals, as well as the cause of mastitis in dairy cattle. vaccines aimed at preventing s. aureus infection in bovine mastitis have been studied for many years, but have so far been unsuccessful due to the complexity of the bacteria, and the lack of suitable vaccine delivery vehicles. the current study developed an escherichia coli protein expression system that produced a recombinant staphy ...201222429499
effect of dietary copper source on response to coliform mastitis in dairy cows.the effect of organic or inorganic dietary cu on escherichia coli mastitis was investigated in first-lactation heifers. twenty-eight primigravid holstein heifers were assigned to 3 treatments in a completely randomized block design with 10 blocks of 3 animals grouped by expected calving date. treatments were as follows: basal diet [7.1 mg cu/kg of dry matter (dm); con] and diets supplemented with cu (10 mg/kg of dm) as cu sulfate (cus) or as cu proteinate (cup). treatments were fed individually ...201222281330
molecular characterization of shiga toxin-producing escherichia coli isolated from the environment of a dairy farm.environmental samples were taken from ground, cattle water troughs, and feeders from a dairy farm with different stec prevalence between animal categories (weaning calves, rearing calves, and dairy cows). overall, 23 % of samples were positive for stx genes, stx(2) being the most prevalent type. isolates were analyzed by pcr monoplex to confirm generic e. coli and by two multiplex pcr to investigate the presence of stx(1), stx(2), eae, saa, ehxa, and other putative virulence genes encoded in ste ...201222706777
the effect of intrauterine administration of mannose or bacteriophage on uterine health and fertility of dairy cows with special focus on escherichia coli and arcanobacterium pyogenes.the objective of this study was to evaluate the effects of intrauterine administration of 50 g of ultrapure mannose or a bacteriophage cocktail and the presence of escherichia coli and arcanobacterium pyogenes in the uterine lumen on uterine health and reproductive performance of lactating dairy cows. the study was conducted on a commercial dairy farm located near ithaca, new york, from may 4 to january 20, 2011, and 597 cows were enrolled. the cows were divided randomly into 3 treatment groups, ...201222612946
amino acid differences in interferon-tau (ifn-τ) of bos taurus coreanae and holstein.interferons (ifns) are commonly grouped into type i and type ii ifn. type i ifns are known as antiviral ifns including ifn-α, ifn-β, and ifn-ω whereas type ii ifn is referred to immune ifn and ifn-γ is only member of the type ii ifn. type i ifns are induced by virus invading however type ii ifn is produced by mitogenic or antigenic stimuli. ifn-τ was first identified in ruminant ungulates as a pregnancy recognition hormone, trophoblastin. ifn-τ constitutes a new class of type i ifn, which posses ...201222578803
a bayesian variable selection procedure to rank overlapping gene sets.genome-wide expression profiling using microarrays or sequence-based technologies allows us to identify genes and genetic pathways whose expression patterns influence complex traits. different methods to prioritize gene sets, such as the genes in a given molecular pathway, have been described. in many cases, these methods test one gene set at a time, and therefore do not consider overlaps among the pathways. here, we present a bayesian variable selection method to prioritize gene sets that overc ...201222554182
variable within- and between-herd diversity of ctx-m cephalosporinase-bearing escherichia coli isolates from dairy cattle.bla(ctx-m) beta-lactamases confer resistance to critically important cephalosporin drugs. recovered from both hospital- and community-acquired infections, bla(ctx-m) was first reported in u.s. livestock in 2010. it has been hypothesized that veterinary use of cephalosporins in livestock populations may lead to the dissemination of beta-lactamase-encoding genes. therefore, our objectives were to estimate the frequency and distribution of coliform bacteria harboring bla(ctx-m) in the fecal flora o ...201222544245
local and systemic response to intramammary lipopolysaccharide challenge during long-term manipulated plasma glucose and insulin concentrations in dairy cows.the metabolic load during periods of high milk production in dairy cows causes a variety of changes of metabolite blood concentrations including dramatically decreased glucose levels. these changes supposedly impair the immune system. the goal of this study was, therefore, to evaluate adaptations of the cow's immune system in response to an intramammary lipopolysaccharide (lps) stimulation during a 3-d modification of plasma glucose and insulin induced by different clamp infusions. seventeen mid ...201222541481
in vitro effects of escherichia coli lipopolysaccharide on the function and gene expression of neutrophils isolated from the blood of dairy cows.the objectives of this study were to investigate the effect of escherichia coli lipopolysaccharide (lps) on the function of bovine neutrophils (pmnl) collected from mid lactation cows and determine the differential effects of lps on gene expression of pmnl purified from early and mid lactation cows. the pmnl from mid lactation cows (187±13 d postpartum) were incubated with 0, 1, 25, and 50 μg/ml of lps for 120 min, and the generation of reactive oxygen species (ros), pmnl extracellular traps (ne ...201222541470
the effect of multiplex-pcr-assessed major pathogens causing subclinical mastitis on somatic cell profiles.the major pathogens causing mastitis were evaluated by multiplex-polymerase chain reaction (m-pcr) with self-designed primers in four quarters of the first, third, and fifth parities in industrial, semi-industrial, and traditional dairy cattle farms in iran. with the incidence of infection in the quarters by staphylococcus aureus and streptococcus agalactiae, the mean log somatic cell count (log scc) increased from 5.06 to 5.77. the smallest changes occurred with escherichia coli. contagious pat ...201222535149
transcriptional profiling of the bovine hepatic response to experimentally induced e. coli mastitis.the mammalian liver works to keep the body in a state of homeostasis and plays an important role in systemic acute phase response to infections. in this study we investigated the bovine hepatic acute phase response at the gene transcription level in dairy cows with experimentally escherichia coli-induced mastitis. at time = 0, each of 16 periparturient dairy cows received 20-40 colony-forming units of live e. coli in one front quarter of the udder. a time series of liver biopsies was collected a ...201222496490
evaluation of the effectiveness of intrauterine treatment with formosulphathiazole of clinical endometritis in postpartum dairy cows.in cattle, elimination of bacterial contamination from the uterine lumen after parturition is often delayed or compromised, and pathogenic bacteria can persist, causing uterine disease and infertility. the aim of this study was to compare the clinical and bacteriologic recovery following a single intrauterine administration of formosulphatiazole, cephapirin or placebo in cows with clinical endometritis. cows (n = 80), no less than 28 days postpartum, with clinical endometritis were enrolled in t ...201222464185
occurrence and characteristics of virulence genes of escherichia coli strains isolated from healthy dairy cows in inner mongolia, china.virulence genes of escherichia coli (e. coli) isolates from healthy dairy cows were identified and characterized by a multiplex pcr assay and serogrouping test. the results showed that among the target genes, eaea was most frequently detected, accounting for 22.11% (67/303) in all strains from 101 cows. for categorization of e. coli, aepec was the category with widest distribution detected in 55 (18.15%) strains from 22 cattle. all of 84 pcr-positive strains belonged to 14 o serogroups, and o149 ...201224031860
effect of enterotoxigenic escherichia coli vaccine on innate immune function of bovine mammary gland infused with lipopolysaccharide.the effects of using an enterotoxigenic escherichia coli vaccine on innate immune responses following intramammary infusion of lipopolysaccharide (lps) were investigated in midlactation holstein-friesian cows. seven out of 14 cows were inoculated with e. coli vaccine. three weeks later, 100 μg of lps dissolved in 10 ml of saline was infused into 1 quarter of all cows. milk was collected every hour from infusion to 12 h after infusion, and twice daily (at 0900 and 1600 h) for 4 d. blood samples w ...201222916910
type 1 and type 2 immune response profiles of commercial dairy cows in 4 regions across canada.diseases of dairy cattle have adverse implications for both the dairy industry and animal welfare. understanding adaptive immune response profiles of cattle on a national scale will provide insight into the potential for improving health and decreasing disease. the objectives of the present study were to evaluate immune response phenotypes of holstein cows outside the peripartum period and to determine if antibody isotype bias to putative type 1 and type 2 test antigens is maintained. the cows, ...201223024454
relationship between bacteriological findings in the second and fourth weeks postpartum and uterine infection in dairy cows considering bacteriological results.the uterine lumen in early postpartum dairy cows is contaminated with different bacteria. the most relevant uterine pathogens are escherichia coli and trueperella pyogenes. prevalence of α-hemolytic streptococci and coagulase-negative staphylococci (cns) is also high; however, these pathogens are considered opportunistic. the overall objective of this study was to investigate effects of the intrauterine presence of e. coli, t. pyogenes, α-hemolytic streptococci, or cns at 10±1 d in milk (dim) on ...201223021749
cdna, genomic sequence cloning and overexpression of giant panda (ailuropoda melanoleuca) mitochondrial atp synthase atp5g1.the atp5g1 gene is one of the three genes that encode mitochondrial atp synthase subunit c of the proton channel. we cloned the cdna and determined the genomic sequence of the atp5g1 gene from the giant panda (ailuropoda melanoleuca) using rt-pcr technology and touchdown-pcr, respectively. the cloned cdna fragment contains an open reading frame of 411 bp encoding 136 amino acids; the length of the genomic sequence is of 1838 bp, containing three exons and two introns. alignment analysis revealed ...201223007995
virulence genes in isolates of escherichia coli from samples of milk and feces from dairy cattle.the aim of this work was to determine if escherichia coli isolates carrying the virulence genes eae and eltb and exhibiting the ehly phenotype are present in feces and milk samples from healthy dairy cattle on farms. isolates from calves showed a statistically higher prevalence of eae and eltb compared with isolates from older animals. the other factors tested (stx(1), stx(2), and ehly) were not statistically different between the two groups. two isolates originating from calf feces were identif ...201222947478
the effects of experimentally induced escherichia coli mastitis and flunixin meglumine administration on activity measures, feed intake, and milk parameters.the use of flunixin meglumine (fm), a nonsteroidal antiinflammatory drug, during experimentally induced escherichia coli mastitis was evaluated. twenty-four primiparous and multiparous lactating dairy cows were challenged with 1×10(2) cfu of e. coli 727 in 1 uninfected quarter. of the 24 e. coli-challenged animals, 12 were administered fm [ecf; 100mg (2 cc)/45.5 kg of body weight) at the onset of clinical mastitis signs. the remaining 12 challenged cows were untreated (ec). an additional 11 cows ...201222916898
compromised neutrophil function and bovine e. coli mastitis: is c5a the missing link?during early lactation, dairy cow are prone to developing severe mastitis in responses to intramammary escherichia coli infections. these severe inflammatory responses have been correlated with reduced neutrophil function during the periparturient period. however, the causative mechanism of neutrophil dysfunction has not been elucidated. studies in murine sepsis models have shown that during sepsis neutrophils are functionally paralysed due to the presence of high concentrations of complement fa ...201222858435
escherichia coli lipopolysaccharide administration transiently suppresses luteal structure and function in diestrous cows.the objective was to characterize the effects of escherichia coli lipopolysaccharide (lps) endotoxin (given i.v.) on luteal structure and function. seven nonlactating german holstein cows, 5.1 ± 0.8 years old (mean ± s.e.m.), were given 10  ml saline on day 10 (ovulation=day 1) of a control estrous cycle. on day 10 of a subsequent cycle, they were given 0.5 μg/kg lps. luteal size decreased (from 5.2 to 3.8 cm², p≤0.05) within 24 h after lps treatment and remained smaller throughout the remainder ...201222829687
[verocytotoxigenic escherichia coli: several aspects... and also the dairy farms].verocytotoxigenic escherichia coli (vtec) is associated with outbreaks and sporadic cases of hemorrhagic colitis (hc) and hemolytic-uremic syndrome (hus), the most severe form of these human diseases. in argentina hus is endemic, with 500 new cases per year and an incidence of 17/100,000 in children under 5 years of age. vtec o157:h7 is the most frequently isolated serotype, although there are non-o157 serotypes that have been associated with human disease. vtec produces verocytotoxins and acces ...201223267631
development of a diagnostic method for neosporosis in cattle using recombinant neospora caninum proteins.neosporosis is an infectious disease primarily of cattle and dogs, caused by intracellular parasite, neospora caninum. neosporosis appears to be a major cause of abortion in dairy cattle worldwide and causes to huge economic loss to dairy industry.201222558916
microbial diversity of bovine mastitic milk as described by pyrosequencing of metagenomic 16s rdna.dairy cow mastitis is an important disease in the dairy industry. different microbial species have been identified as causative agents in mastitis, and are traditionally diagnosed by bacterial culture. the objective of this study was to use metagenomic pyrosequencing of bacterial 16s rrna genes to investigate bacterial dna diversity in milk samples of mastitic and healthy dairy cows and compare the results with those obtained by classical bacterial culture. one hundred and thirty-six milk sample ...201223082192
[prokaryotic expression of hn gene of bovine parainfluenza virus type 3 and the establishment of indirect elisa method].the prokaryotic expression plasmid pqe30-hn of hemagglutinin-neuraminidase (hn) protein gene of bovine parainfluenza virus type 3 (bpiv3) strain hj-1 was expressed by iptg induction in e. coli xl1blue. the recombinant hn protein(rhn) was purified by electroeluting method, and used as coated antigen. an indirect enzyme-linked immunosorbent assay (elisa) was developed to detect the antibody valence of bpiv3. the best working conditions of elisa were as follows: the antigen concentration was 6 micr ...201222416346
microbiological quality indicators in waters of dairy farms: detection of pathogens by pcr in real time.when contaminated water is used to wash the udders of dairy cattle and milking utensils, raw milk may become contaminated with pathogens. washing with high quality water is essential to reduce the microbial contamination of milk. furthermore, the wastewater generated in dairy herds also contains high populations of pathogens, antibiotics and nutrients that more often are thrown into the water bodies without any treatment. in this work, both supply water and wastewater from 20 dairy farms from an ...201222542296
molecular cloning, expression, and immunolocalization of protein disulfide isomerase in excretory-secretory products from clonorchis sinensis.protein disulfide isomerase (pdi) is an essential catalyst of the endoplasmic reticulum with folding and chaperone activities in different biological systems. here, pdi of clonorchis sinensis (cspdi) was isolated from the cdna library of adult c. sinensis. the open reading frame contains 1,317 bp encoding 438 amino acids and shares 53 %, 49 %, and 43 % identity with pdi from bos taurus, homo sapiens, and schistosoma mansoni, respectively. two catalytic thioredoxin motifs cxxc were found in this ...201222538482
serotypes, virulence genes, and intimin types of shiga toxin-producing escherichia coli and enteropathogenic escherichia coli isolated from mastitic milk relevant to human health in egypt.abstract some foodborne pathogens can cause mastitis, in which the organism is directly excreted into milk. therefore, we undertook the steps to determine the prevalence and molecular characteristics of shiga toxin-producing escherichia coli (stec) isolates from bovine mastitic milk in egypt. forty milk samples from dairy cattle showing mastitis were collected and examined for the presence of e. coli. following enrichment and plating on selective agar, confirmation of the isolates was based on ...201222229945
repeated oral administration of lipopolysaccharide from escherichia coli 0111:b4 modulated humoral immune responses in periparturient dairy cows.the objective of this study was to evaluate the effects of repeated oral exposure to lps on humoral immune responses of periparturient dairy cows. sixteen holstein cows were assigned to two treatment groups 2 wk before the expected day of parturition. cows were administered orally, twice weekly at wk -2, -1 and +1 around parturition, with the following treatments: 3 ml saline; or 3 ml of saline containing lps from escherichia coli 0111:b4. the amount of lps administered during wk -2, -1, and +1 ...201222266418
emerging antimicrobial resistance in commensal escherichia coli with public health relevance.in 2009, 1462 escherichia coli isolates were collected in a systematic resistance monitoring approach from primary production, slaughterhouses and at retail and evaluated on the basis of epidemiological cut-off values. besides resistance to antimicrobial classes that have been extensively used for a long time (e.g. sulphonamides and tetracyclines), resistance to (fluoro)quinolones and third-generation cephalosporins was observed. while in the poultry production chain the majority (60%) of isolat ...201222958260
High diversity and differential persistence of fecal Bacteroidales population spiked into freshwater microcosm.Bacteroidales markers are promising indicators of fecal pollution and are now widely used in microbial source tracking (MST) studies. However, a thorough understanding of the persistence of Bacteroidales population after being released into environmental waters is lacking. We investigated the persistence of two host specific markers (HF183 and CF193) and temporal change of Bacteroidales population over 14 days in freshwater microcosms seeded with human or bovine feces. The concentrations of HF18 ...201222100053
Large-scale preparation and characterization of non-pegylated and pegylated superactive ovine leptin antagonist.Superactive ovine leptin antagonist (SOLA) was prepared by rational mutagenesis of the ovine leptin antagonist L39A/D40A/F41A mutant prepared previously in our lab by mutating wild type leptin to D23L/L39A/D40A/F41A. SOLA was expressed in Escherichia coli as insoluble inclusion bodies, refolded and purified to homogeneity (as evidenced by SDS-PAGE and analytical gel filtration) by ion-exchange chromatography. The purified protein was mono-pegylated at its N terminus by 20-kDa linear pegylation r ...201222040607
Prevalence and Isoforms of the Pathogenicity Island ETT2 Among Escherichia coli Isolates from Colibacillosis in Pigs and Mastitis in Cows.To study the prevalence and isoforms of the pathogenicity island ETT2 among pathogenic Escherichia coli, as well as to determine the relationship between the ETT2 locus and other virulence factors, PCR amplifications target to the 35 ETT2-associated genes were established and used to investigate the presence of the ETT2 locus in 168 E. coli isolates from weaned piglets with edema and/or diarrhea or dairy cows with mastitis. The results showed that the ETT2 locus could be identified in the pathog ...201222002588
milk microbiome signatures of subclinical mastitis-affected cattle analysed by shotgun sequencing.metagenomic analysis of milk samples collected from kankrej, gir (bos indicus) and crossbred (bos taurus × b. indicus) cattle harbouring subclinical mastitis was carried out by next-generation sequencing 454 gs-flx technology to elucidate the microbial community structure of cattle milk.201222277077
Control of tick infestations in cattle vaccinated with bacterial membranes containing surface-exposed tick protective antigens.Vaccines containing the Rhipicephalus (Boophilus) microplus BM86 and BM95 antigens protect cattle against tick infestations. Tick subolesin (SUB), elongation factor 1a (EF1a) and ubiquitin (UBQ) are new candidate protective antigens for the control of cattle tick infestations. Previous studies showed that R. microplus BM95 immunogenic peptides fused to the Anaplasma marginale major surface protein (MSP) 1a N-terminal region (BM95-MSP1a) for presentation on the Escherichia coli membrane were prot ...201222085549
Heparan sulfate proteoglycans mediate the angiogenic activity of the vascular endothelial growth factor receptor-2 agonist gremlin.Heparan sulfate proteoglycans (HSPGs) modulate the interaction of proangiogenic heparin-binding vascular endothelial growth factors (VEGFs) with signaling VEGF receptor-2 (VEGFR2) and neuropilin coreceptors in endothelial cells (ECs). The bone morphogenic protein antagonist gremlin is a proangiogenic ligand of VEGFR2, distinct from canonical VEGFs. Here we investigated the role of HSPGs in VEGFR2 interaction, signaling, and proangiogenic capacity of gremlin in ECs.201121921258
lipopolysaccharide challenge of the mammary gland in bovine induced a transient glandular shift to anaerobic metabolism.support of milk production in modern dairy cows demands a large proportion of its own metabolic resources, such as glucose, which might be required under stressful situations. the aim of the experiment was to test the hypothesis that acute immune stress shifts oxidative metabolism to glycolysis. two mammary quarters in 6 holstein cows were infused with lipopolysaccharide (lps), whereas the 2 counter quarters served as controls to the treatment. an additional 6 cows were infused with saline and s ...201121854919
vaccination with type iii secreted proteins leads to decreased shedding in calves after experimental infection with escherichia coli o157.escherichia coli o157:h7 remains a threat to humans via cattle-derived fecal contamination of food and water. preharvest intervention strategies represent a means of reducing the pathogen burden before harvest. in this study, the efficacy of a commercially produced type iii secreted protein (ttsp) vaccine was evaluated with the use of a commingled experimental calf infection model (30 placebo-treated animals and 30 vaccinates). the calves were vaccinated on days 0, 21, and 42 and infected with 1 ...201121731179
serotypes and virulence profiles of non-o157 shiga toxin-producing escherichia coli isolates from bovine farms.non-o157 shiga toxin-producing escherichia coli (stec) strains are clinically significant food-borne pathogens. however, there is a dearth of information on serotype prevalence and virulence gene distribution, data essential for the development of public health protection monitoring and control activities for the meat and dairy industries. thus, the objective of this study was to examine the prevalence of non-o157 stec on beef and dairy farms and to characterize the isolates in terms of serotype ...201122003024
Selective reduction of the pathogenic load of cow manure in an industrial-scale continuous-feeding vermireactor.Vermicomposting is a suitable technology for processing different wastes, to produce a valuable end product (vermicompost). However, the pathogenic load of the waste must be greatly reduced in order to prevent risks to human health. Although Eisenia andrei may reduce the levels of several pathogens, the feasibility of vermicomposting, with regard to pathogen reduction, has not been tested on an industrial scale. This work studied whether vermicomposting in a continuous feeding vermireactor, is a ...201121875788
Effect of Escherichia coli lipopolysaccharide on u-PA activity and u-PA and u-PAR RNA expression in a bovine mammary epithelial cell line.It is well known that the plasminogen-activating (PA) system plays a key role in the bovine mammary gland during tissue remodelling. However, the modulation of the PA cascade after bacterial infections needs to be elucidated. This study examined the effects of Escherichia coli lipopolysaccharide (LPS) on cell viability, the modulation of cell-associated u-PA activity, and the regulation of u-PA and u-PA receptor (u-PAR) RNA expression using the BME-UV1 bovine mammary epithelial cell line. LPS di ...201122103977
Carbon nanoparticles as detection labels in antibody microarrays. Detection of genes encoding virulence factors in Shiga toxin-producing Escherichia coli.The present study demonstrates that carbon nanoparticles (CNPs) can be used as labels in microarrays. CNPs were used in nucleic acid microarray immunoassays (NAMIAs) for the detection of different Shiga toxin-producing Escherichia coli (STEC) virulence factors: four genes specific for STEC (vt1, vt2, eae, and ehxA) and the gene for E. coli 16S (hui). Optimization was performed using a Box-Behnken design, and the limit of detection for each virulence factor was established. Finally, this NAMIA us ...201121936575
rapid identification of bovine mastitis pathogens by high-resolution melt analysis of 16s rdna sequences.accurate identification of mastitis pathogens is often compromised when using conventional culture-based methods. here, we report a novel, rapid assay tested for speciation of bacterial mastitis pathogens using high-resolution melt analysis (hrma) of 16s rdna sequences. real-time pcr amplification of 16s rrna gene fragment, spanning the variable region v5 and v6 was performed with a resulting amplicon of 290bp. first, a library was generated of melt curves of 9 common pathogens that are implicat ...201121944716
lingual antimicrobial peptide and il-8 expression are oppositely regulated by the antagonistic effects of nf-κb p65 and c/ebpβ in mammary epithelial cells.pathogen contact induces quickly in mammary epithelial cells (mec) the expression of the proinflammatory cytokine il-8 and delayed that of the bactericidal β-defensin lap. both genes encoding these factors feature on their proximal promoter a composite nf-κb/cebp binding site. we compare here in mec the role of nf-κb and c/ebp factors in regulating basal and pathogen-induced expression of both genes from cattle. abrogating nf-κb binding to that site by introduction of a single point mutation blo ...201121255844
cdna, genomic sequence cloning and overexpression of the ribosomal protein s13 gene in the giant panda (ailuropoda melanoleuca).the cdna and the genomic sequence of ribosomal protein s13 (rps13) of the giant panda (ailuropoda melanoleuca) was cloned using reverse transcription-polymerase chain reaction (rt-pcr) and touchdown-pcr, respectively. these two sequences were sequenced and analyzed, and the cdna of the rps13 gene was overexpressed in escherichia coli bl21. we compared the nucleotide sequences of the coding region and the amino acid sequences with those of seven other mammalian species retrieved from genbank. the ...201121268784
long target droplet polymerase chain reaction with a microfluidic device for high-throughput detection of pathogenic bacteria at clinical sensitivity.in this article we present a long target droplet polymerase chain reaction (pcr) microsystem for the amplification of the 16s ribosomal rna gene. it is used for detecting gram-positive and gram-negative pathogens at high-throughput and is optimised for downstream species identification. the miniaturised device consists of three heating plates for denaturation, annealing and extension arranged to form a triangular prism. around this prism a fluoropolymeric tubing is coiled, which represents the r ...201121271358
a prebiotic, celmanax™, decreases escherichia coli o157:h7 colonization of bovine cells and feed-associated cytotoxicity in vitro.abstract:201121473767
a novel organic-inorganic hybrid monolith for trypsin immobilization.in proteomics, attention has focused on various immobilized enzyme reactors (imers) for the realization of high throughput digestion. in this report, a novel organic-inorganic hybrid monolith based imer was prepared in a 100 μm i.d. capillary with 3-glycidoxypropyltrimethoxysilane (glymo) as the monomer and tetraethoxysilane (teos) as the crosslinker. trypsin immobilization was achieved via the reaction between vicinal diol groups, which were obtained from hydrolysis of epoxy groups, and the ami ...201121253871
differentiation of fecal escherichia coli from human, livestock, and poultry sources by rep-pcr dna fingerprinting on the shellfish culture area of east china sea.the rep-pcr dna fingerprinting performed with rep, box a1r, and (gtg)(5) primers was investigated as a way to differentiate between human, livestock, and poultry sources of fecal pollution on the area of xiangshan bay, east china sea. of the three methods, the box-pcr dna fingerprints analyzed by jack-knife algorithm were revealed high rate of correct classification (rcc) with 91.30, 80.39, 89.39, 86.14, 93.24, 87.72, and 89.28% of human, cattle, swine, chicken, duck, sheep, and goose e. coli is ...201121279641
assessment of an extraction protocol to detect the major mastitis-causing pathogens in bovine milk.despite all efforts to control its spread, mastitis remains the most costly disease for dairy farmers worldwide. one key component of better control of this disease is identification of the causative bacterial agent during udder infections in cows. mastitis is complex, however, given the diversity of pathogens that must be identified. development of a rapid and efficient bacterial species identification tool is thus necessary. this study was conducted to demonstrate the feasibility of bacterial ...201121524507
Carriage of Shiga-toxigenic Escherichia coli by native marsupials in Australia.Shiga-toxigenic strains of Escherichia coli (STEC) are zoonotic pathogens with human health, meat processing and trade impacts. Cattle are the principal reservoirs of STEC, although other animals can be carriers. The STEC status of Australian native marsupials has not been formatively described to date. The aim of the current study was to investigate carriage of STEC by native Australian marsupials in Southeast Queensland. Faeces from a variety of marsupial species, stratified by gastrointestina ...201121917387
host-response patterns of intramammary infections in dairy cows.many different bacterial species have the ability to cause an infection of the bovine mammary gland and the host response to these infections is what we recognize as mastitis. in this review we evaluate the pathogen specific response to the three main bacterial species causing bovine mastitis: escherichia coli, streptococcus uberis and staphylococcus aureus. in this paper we will review the bacterial growth patterns, host immune response and clinical response that results from the intramammary i ...201121955443
insights into mucosal innate responses to escherichia coli o157 : h7 colonization of cattle by mathematical modelling of excretion dynamics.mathematical model-based statistical inference applied to within-host dynamics of infectious diseases can help dissect complex interactions between hosts and microbes. this work has applied advances in model-based inference to understand colonization of cattle by enterohaemorrhagic escherichia coli o157 : h7 at the terminal rectum. a mathematical model was developed based on niche replication and transition rates at this site. a nested-model comparison, applied to excretion curves from 25 calves ...201121849385
Arcanolysin is a cholesterol-dependent cytolysin of the human pathogen Arcanobacterium haemolyticum.Arcanobacterium haemolyticum is an emerging human pathogen that causes pharyngitis, wound infections, and a variety of occasional invasive diseases. Since its initial discovery in 1946, this Gram positive organism has been known to have hemolytic activity, yet no hemolysin has been previously reported. A. haemolyticum also displays variable hemolytic activity on laboratory blood agar that is dependent upon which species the blood is derived.201122029628
effect of a nutritional reconditioning program for thin dairy cattle on body weight, carcass quality, and fecal pathogen shedding.to assess changes in body weight, carcass quality, and fecal pathogen shedding in cull dairy cows fed a high-energy ration for 28 or 56 days prior to slaughter.201122129125
lipopolysaccharide and lipoteichoic acid induce different immune responses in the bovine mammary gland.different pathogens, such as escherichia coli and staphylococcus aureus, can be responsible for different outcomes of mastitis; that is, acute and severe or chronic and subclinical. these differences in the disease could be related to different mammary responses to the pathogens. the objective of this study was to determine if intramammary challenge with the endotoxins lipopolysaccharide (lps), from e. coli, and lipoteichoic acid (lta), from staph. aureus, induce different immune responses in vi ...201122032363
comparative genomics of multidrug resistance-encoding inca/c plasmids from commensal and pathogenic escherichia coli from multiple animal sources.incompatibility group a/c (inca/c) plasmids have received recent attention for their broad host range and ability to confer resistance to multiple antimicrobial agents. due to the potential spread of multidrug resistance (mdr) phenotypes from foodborne pathogens to human pathogens, the dissemination of these plasmids represents a public health risk. in this study, four animal-source inca/c plasmids isolated from escherichia coli were sequenced and analyzed, including isolates from commercial dai ...201121858108
use of model super-shedders to define the role of pen floor and hide contamination in the transmission of escherichia coli o157:h7.super-shedders, cattle shedding at least 10(4) cfu of escherichia coli o157:h7 per gram of feces, increase the risks of contaminating the food chain and disseminating the organism through cattle populations. because detecting super-shedders in cattle populations is laborious and time-consuming, a study was conducted to evaluate the role of hide and pen-floor contamination by model super shedders (mss) in transmission of e. coli o157:h7. steers (n = 48) negative for e. coli o157:h7 were allocated ...201120852081
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