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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
presence of escherichia coli, trueperella pyogenes, α-hemolytic streptococci, and coagulase-negative staphylococci and prevalence of subclinical endometritis.subclinical endometritis (sce) has a severe negative effect on reproductive performance of dairy cows. different studies have shown a wide variety of cut points for the polymorphonuclear neutrophilic leukocyte (pmnl) percentage to define sce and differing sampling times. possible risk factors for sce, such as low body condition score, hyperketonemia, and increased haptoglobin concentrations have been demonstrated. the aim of this study was to determine the relationship between bacterial findings ...201323910551
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
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
effects of combined liver and udder biopsying on the acute phase response of dairy cows with experimentally induced e. coli mastitis.a minimally invasive biopsy technique was evaluated for udder tissue collection in dairy cows with escherichia coli mastitis. meanwhile, the effect of taking repeated liver and udder biopsies on the systemic and local acute phase response (apr) of the dairy cows was investigated during the disease. the cows were divided into a biopsy group (b) (n = 16) and a no-biopsy group (nb) (n = 16) and were sampled in the acute disease stage and in the recovery stage. the cows' pre-disease period served as ...201323867091
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
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
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
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
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
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
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
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
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
prevalence of extended-spectrum β-lactamase-producing escherichia coli on bavarian dairy and beef cattle farms.extended-spectrum β-lactamase (esbl)-producing escherichia coli strains are believed to be widely distributed among humans and animals; however, to date, there are only few studies that support this assumption on a regional or countrywide scale. therefore, a study was designed to assess the prevalence of esbl-producing e. coli in dairy cows and beef cattle in the southern part of bavaria, germany. the study population included 30 mixed dairy and beef cattle farms and 15 beef cattle farms. fecal ...201323455336
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
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
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
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
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
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
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 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
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
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
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
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 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
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
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
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
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
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
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
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
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
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
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
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
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
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
[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
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
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
[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
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
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
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
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
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
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
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
comparative analysis of espf variants in inhibition of escherichia coli phagocytosis by macrophages and inhibition of e. coli translocation through human- and bovine-derived m cells.the espf protein is secreted by the type iii secretion system of enteropathogenic and enterohemorrhagic escherichia coli (epec and ehec, respectively). espf sequences differ between ehec o157:h7, ehec o26:h11, and epec o127:h6 in terms of the number of sh3-binding polyproline-rich repeats and specific residues in these regions, as well as residues in the amino domain involved in cellular localization. espf(o127) is important for the inhibition of phagocytosis by epec and also limits epec translo ...201121875965
Mainstreams of horizontal gene exchange in enterobacteria: consideration of the outbreak of enterohemorrhagic E. coli O104:H4 in Germany in 2011.Escherichia coli O104:H4 caused a severe outbreak in Europe in 2011. The strain TY-2482 sequenced from this outbreak allowed the discovery of its closest relatives but failed to resolve ways in which it originated and evolved. On account of the previous statement, may we expect similar upcoming outbreaks to occur recurrently or spontaneously in the future? The inability to answer these questions shows limitations of the current comparative and evolutionary genomics methods.201122022434
European starlings (Sturnus vulgaris) challenged with Escherichia coli O157 can carry and transmit the human pathogen to cattle.European starlings (Sturnus vulgaris) are an invasive species in the United States and are considered a nuisance pest to agriculture. The goal of this study was to determine the potential for these birds to be reservoirs and/or vectors for the human pathogen Escherichia coli O157:H7.201121985308
a perspective on the prevalence of dna enteric virus genomes in anaerobic-digested biological wastes.the major goal of this study is to gain a perspective on the prevalence of dna enteric virus genomes in mesophilic anaerobic-digested (mad) sewage sludge and manure by comparing their quantitative pcr (qpcr) concentrations and removals with traditional fecal indicators (escherichia coli, enterococci, and bacteroidetes). in addition, relationships between qpcr and culture measurements of fecal indicators (fis) were determined. there was no significant difference between the qpcr concentrations of ...201121931949
intermittent parenteral administration of endotoxin triggers metabolic and immunological alterations typically associated with displaced abomasum and retained placenta in periparturient dairy cows.this study sought to investigate the effects of induced intermittent endotoxemia on plasma mediators of carbohydrate and lipid metabolism, humoral immunity, and clinical health status in periparturient dairy cows. sixteen pregnant holstein cows were blocked by parity and day of calving, and were randomly allocated to 1 of 2 different treatment groups. eight cows were infused intravenously (i.v.) with 100ml of sterile saline and served as the control group (con). the other 8 cows were infused i.v ...201121943748
intracellular reactive oxygen species production by polymorphonuclear leukocytes in bovine leukemia virus-infected dairy cows.the present study assesses the oxidative burst activity from polymorphonuclear leukocytes (pmnl) from bovine leukemia virus (blv)-infected cows. fifteen clinically healthy cows were divided in serologically positive cows without any hematological alteration, serologically positive animals with persistent lymphocytosis (pl) and healthy serologically negative cows. the oxidative burst activity from pmnl was evaluated by flow cytometry using 2',7'-dichlorofluorescein diacetate as a probe. pmnl from ...201121937857
Profile of Shiga toxin-producing Escherichia coli strains isolated from dogs and cats and genetic relationships with isolates from cattle, meat and humans.Pets can be reservoirs of Shiga toxin-producing Escherichia coli (STEC) strains. The aim of this study was to examine nine strains belonging to several serotypes (O91:H21, O91:H16, O178:H19, O8:H19, O22:H8, O22:HNT, ONT:H8), previously recovered from cats or dogs. To this end, we assessed a set of additional virulence genes (stx(2) subtype, subAB, ehxA, eae and saa), cytotoxic activity, and genetic relationships with strains isolated from cattle, meat and humans using pulsed-field gel electropho ...201122119188
Identification of source of faecal pollution of Tirumanimuttar River, Tamilnadu, India using microbial source tracking.Efficient management of deteriorating water bodies can be achieved by determining the sources of faecal pollution. Resourceful techniques for discrimination of the sources of Escherichia coli in surface water have recently been developed, including the use of river water to facilitate faecal indicator surveillance, identification of sources of faecal contamination and employing relevant management practices to maintain water quality. This study was conducted to employ microbial source tracking ( ...201122016043
a potential test system for detecting contaminations by bacterial lipoproteins.biological specimens are often contaminated with bacteria-derived products such as lps or lipoproteins (lp), which trigger unwanted inflammatory responses in hosts. whereas a contamination by lps can be determined by various test systems, a contamination by lp can as yet not be determined. tlr4 and tlr2 are key components of the lps and the lp receptor complex, respectively. it was tested in this study whether hek293 cell stably transfected with bovine tlr2 have the ability to react to low conce ...201122133281
Reproductive tract defense and disease in postpartum dairy cows.This paper briefly reviews recent data and concepts on the development and mitigation of infection and inflammation in the reproductive tract of dairy cows during the first 2 mo after calving. The incidence of metritis is typically between 10 and 20%, of clinical endometritis or purulent vaginal discharge (PVD) approximately 15%, and of subclinical or cytological endometritis a further 15%. Worse postpartum negative energy balance is associated with more severe or prolonged uterine inflammation. ...201121890187
serum concentration and mrna expression in milk somatic cells of toll-like receptor 2, toll-like receptor 4, and cytokines in dairy cows following intramammary inoculation with escherichia coli.the objective of the current study was to investigate the toll-like receptors (tlr), including the soluble forms stlr2 and stlr4, involved in innate immune responses of dairy cows to experimentally induced escherichia coli mastitis. six clinically healthy holstein dairy cows received an intramammary inoculation of e. coli o111:k58 between 63 and 83 d postpartum. concentrations of stlr2 and stlr4, the proinflammatory cytokines il-6 and tumor necrosis factor-α (tnf-α), and acute phase proteins ser ...201122118081
escherichia coli o157:h7 populations in ruminants can be reduced by orange peel product feeding.foodborne pathogenic bacteria such as escherichia coli o157:h7 are threats to the safety of beef. citrus peel and dried orange pulp are by-products from citrus juice production that have natural antimicrobial effects and are often incorporated into least-cost ration formulations for beef and dairy cattle. this study was designed to determine if orange peel and pulp affected e. coli o157:h7 populations in vivo. sheep (n = 24) were fed a cracked corn grain-based diet that was supplemented with a ...201122054194
recent reports about enzymes related to the synthesis of prostaglandin (pg) f2 (pgf2α and 9α, 11β-pgf2).prostaglandin (pg) f(2α) is widely distributed in various organs and exhibits various biological functions, such as luteolysis, parturition, aqueous humor homeostasis, vasoconstriction, rennin secretion, pulmonary fibrosis and so on. the first enzyme reported to synthesize pgf(2) was referred to as pgf synthase belonging to the aldo-keto reductase (akr) 1c family, and later pgf(2α) synthases were isolated from protozoans and designated as members of the akr5a family. in 2003, akr1b5, which is hi ...201121926128
molecular epidemiology of mastitis pathogens of dairy cattle and comparative relevance to humans.mastitis, inflammation of the mammary gland, can be caused by a wide range of organisms, including gram-negative and gram-positive bacteria, mycoplasmas and algae. many microbial species that are common causes of bovine mastitis, such as escherichia coli, klebsiella pneumoniae, streptococcus agalactiae and staphylococcus aureus also occur as commensals or pathogens of humans whereas other causative species, such as streptococcus uberis, streptococcus dysgalactiae subsp. dysgalactiae or staphyloc ...201121968538
optimization of in-house elisa based on recombinant major sperm protein (rmsp) of dictyocaulus viviparus for the detection of lungworm infection in cattle.the aim of this study was to optimize an in-house elisa based on a recombinant version of the major sperm protein (msp) of dictyocaulus viviparus for routine diagnosis of lungworm infection in cattle. a recombinant msp (rmsp) was cloned into pgex-6p-1 vector and expressed as a glutathione-s-transferase (gst) fusion protein in escherichia coli bl21 (de3) chemically competent cells. the product was then employed as capture antigen in an elisa, and validated against 304 samples of known status (216 ...201122019470
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
the effect of recurrent episodes of clinical mastitis caused by gram-positive and gram-negative bacteria and other organisms on mortality and culling in holstein dairy cows.the objective of this study was to estimate the effects of recurrent episodes of different types of clinical mastitis (cm) caused by gram-positive (streptococcus spp., staphylococcus aureus, staphylococcus spp.) and gram-negative (escherichia coli, klebsiella, citrobacter, enterobacter, pseudomonas) bacteria, and other organisms (arcanobacterium pyogenes, mycoplasma, corynebacterium bovis, yeast, miscellaneous) on the probability of mortality and culling in holstein dairy cows. data from 30,233 ...201121943738
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
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
Association between virulence factors of Escherichia coli, Fusobacterium necrophorum, and Arcanobacterium pyogenes and uterine diseases of dairy cows.The objective of this study was to evaluate the relationship between bacterial species-specific virulence factors (VFs) present in the uterus at 3 different stages of lactation (1-3, 8-10, and 34-36 days in milk (DIM)) and the incidence of metritis and clinical endometritis in dairy cows. The following VF genes were investigated: plo (pyolysin), cbpA (collagen-binding protein), and fimA (fimbriae expression) which are Arcanobacterium pyogenes specific; fimH (a type 1 pilus component), Escherichi ...201122186615
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