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1.
Methods Mol Biol ; 2291: 19-86, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33704748

RESUMO

Cattle and other ruminants are primary reservoirs for Shiga toxin-producing Escherichia coli (STEC) strains which have a highly variable, but unpredictable, pathogenic potential for humans. Domestic swine can carry and shed STEC, but only STEC strains producing the Shiga toxin (Stx) 2e variant and causing edema disease in piglets are considered pathogens of veterinary medical interest. In this chapter, we present general diagnostic workflows for sampling livestock animals to assess STEC prevalence, magnitude, and duration of host colonization. This is followed by detailed method protocols for STEC detection and typing at genetic and phenotypic levels to assess the relative virulence exerted by the strains.


Assuntos
Doenças dos Bovinos , Infecções por Escherichia coli , Toxina Shiga II/metabolismo , Escherichia coli Shiga Toxigênica , Doenças dos Suínos , Animais , Bovinos , Doenças dos Bovinos/diagnóstico , Doenças dos Bovinos/metabolismo , Doenças dos Bovinos/microbiologia , Infecções por Escherichia coli/diagnóstico , Infecções por Escherichia coli/metabolismo , Infecções por Escherichia coli/microbiologia , Infecções por Escherichia coli/veterinária , Escherichia coli Shiga Toxigênica/classificação , Escherichia coli Shiga Toxigênica/isolamento & purificação , Escherichia coli Shiga Toxigênica/metabolismo , Escherichia coli Shiga Toxigênica/patogenicidade , Suínos , Doenças dos Suínos/diagnóstico , Doenças dos Suínos/metabolismo , Doenças dos Suínos/microbiologia
2.
Appl Environ Microbiol ; 87(6)2021 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-33397699

RESUMO

Little is known about the drivers of critically important antibacterial resistance in species with zoonotic potential present on farms (e.g., CTX-M ß-lactamase-positive Escherichia coli). We collected samples monthly between January 2017 and December 2018 on 53 dairy farms in South West England, along with data for 610 variables concerning antibacterial usage, management practices, and meteorological factors. We detected E. coli resistant to amoxicillin, ciprofloxacin, streptomycin, and tetracycline in 2,754/4,145 (66%), 263/4,145 (6%), 1,475/4,145 (36%), and 2,874/4,145 (69%), respectively, of samples from fecally contaminated on-farm and near-farm sites. E. coli positive for bla CTX-M were detected in 224/4,145 (5.4%) of samples. Multilevel, multivariable logistic regression showed antibacterial dry cow therapeutic choice (including use of cefquinome or framycetin) to be associated with higher odds of bla CTX-M positivity. Low average monthly ambient temperature was associated with lower odds of bla CTX-M E. coli positivity in samples and with lower odds of finding E. coli resistant to each of the four test antibacterials. This was in addition to the effect of temperature on total E. coli density. Furthermore, samples collected close to calves had higher odds of having E. coli resistant to each antibacterial, as well as E. coli positive for bla CTX-M Samples collected on pastureland had lower odds of having E. coli resistant to amoxicillin or tetracycline, as well as lower odds of being positive for bla CTX-M IMPORTANCE Antibacterial resistance poses a significant threat to human and animal health and global food security. Surveillance for resistance on farms is important for many reasons, including tracking impacts of interventions aimed at reducing the prevalence of resistance. In this longitudinal survey of dairy farm antibacterial resistance, we showed that local temperature-as it changes over the course of a year-was associated with the prevalence of antibacterial-resistant E. coli We also showed that prevalence of resistant E. coli was lower on pastureland and higher in environments inhabited by young animals. These findings have profound implications for routine surveillance and for surveys carried out for research. They provide important evidence that sampling at a single time point and/or single location on a farm is unlikely to be adequate to accurately determine the status of the farm regarding the presence of samples containing resistant E. coli.


Assuntos
Farmacorresistência Bacteriana , Escherichia coli/genética , beta-Lactamases/genética , Envelhecimento , Amoxicilina/farmacologia , Animais , Antibacterianos/farmacologia , Bovinos , Doenças dos Bovinos/microbiologia , Ciprofloxacino/farmacologia , Escherichia coli/efeitos dos fármacos , Escherichia coli/isolamento & purificação , Infecções por Escherichia coli/microbiologia , Fazendas , Fezes/microbiologia , Estreptomicina/farmacologia , Temperatura , Tetraciclina/farmacologia
3.
J Med Microbiol ; 70(2)2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33404383

RESUMO

Introduction. Moraxella bovoculi is frequently isolated from the eyes of cattle with infectious bovine keratoconjunctivitis (IBK; pinkeye). As with M. bovis, which has been causally linked to IBK, M. bovoculi expresses an RTX (repeats in the structural toxin) cytotoxin that is related to M. bovis cytotoxin. Pilin, another pathogenic factor in M. bovis, is required for corneal attachment. Seven antigenically distinct pilin serogroups have been described in M. bovis.Hypothesis/Gap Statement. Multiple different serogroups exist amongst type IV pilin encoded by M. bovis, however, it is not known whether M. bovoculi exhibits a similar degree of diversity in type IV pilin that it encodes.Aim. This study was done to characterize a structural pilin (PilA) encoded by M. bovoculi isolated from cases of IBK to determine if diversity exists amongst PilA sequences.Methodology. Ninety-four isolates of M. bovoculi collected between 2002 and 2017 from 23 counties throughout California and from five counties in four other Western states were evaluated.Results. DNA sequencing and determination of deduced amino acid sequences revealed ten (designated groups A through J) unique PilA sequences that were ~96.1-99.3 % identical. Pilin groups A and C matched previously reported putative PilA sequences from M. bovoculi isolated from IBK-affected cattle in the USA (Virginia, Nebraska, and Kansas) and Asia (Kazakhstan). The ten pilin sequences identified were only ~74-76 % identical to deduced amino acid sequences of putative pilin proteins identified from the previously reported whole-genome sequences of M. bovoculi derived from deep nasopharyngeal swabs of IBK-asymptomatic cattle.Conclusions. Compared to the diversity reported between structural pilin proteins amongst different serogroups of M. bovis, M. bovoculi PilA from geographically diverse isolates derived from IBK-affected cattle are more conserved.


Assuntos
Proteínas de Fímbrias/genética , Fímbrias Bacterianas/genética , Ceratoconjuntivite/veterinária , Moraxella/patogenicidade , Infecções por Moraxellaceae/veterinária , Sequência de Aminoácidos/genética , Animais , Bovinos , Doenças dos Bovinos/microbiologia , Proteínas de Fímbrias/metabolismo , Variação Genética/genética , Genoma Bacteriano/genética , Ceratoconjuntivite/microbiologia , Moraxella/genética , Moraxella/isolamento & purificação , Infecções por Moraxellaceae/diagnóstico
4.
Nat Commun ; 12(1): 161, 2021 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-33420064

RESUMO

Calf diarrhea is associated with enteric infections, and also provokes the overuse of antibiotics. Therefore, proper treatment of diarrhea represents a therapeutic challenge in livestock production and public health concerns. Here, we describe the ability of a fecal microbiota transplantation (FMT), to ameliorate diarrhea and restore gut microbial composition in 57 growing calves. We conduct multi-omics analysis of 450 longitudinally collected fecal samples and find that FMT-induced alterations in the gut microbiota (an increase in the family Porphyromonadaceae) and metabolomic profile (a reduction in fecal amino acid concentration) strongly correlate with the remission of diarrhea. During the continuous follow-up study over 24 months, we find that FMT improves the growth performance of the cattle. This first FMT trial in ruminants suggest that FMT is capable of ameliorating diarrhea in pre-weaning calves with alterations in their gut microbiota, and that FMT may have a potential role in the improvement of growth performance.


Assuntos
Doenças dos Bovinos/terapia , Bovinos/crescimento & desenvolvimento , Diarreia/terapia , Transplante de Microbiota Fecal/veterinária , Microbioma Gastrointestinal/genética , Animais , Bacteroidaceae/genética , Bacteroidaceae/isolamento & purificação , Bovinos/microbiologia , Doenças dos Bovinos/sangue , Doenças dos Bovinos/metabolismo , Doenças dos Bovinos/microbiologia , DNA Bacteriano/isolamento & purificação , Diarreia/sangue , Diarreia/metabolismo , Diarreia/microbiologia , Fezes/microbiologia , Feminino , Seguimentos , Genômica , Masculino , Metabolômica , RNA Ribossômico 16S/genética , Resultado do Tratamento
5.
J Dairy Sci ; 104(2): 2290-2301, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33358167

RESUMO

Branched-chain fatty acids (BCFA) have recently been reported to play a role in human gut health during early life. However, little information is available on the fecal BCFA profiles in young ruminants and whether they are associated with the development of neonatal calf diarrhea. The objectives of this study were to (1) characterize BCFA profiles in feces collected from young calves, (2) compare the fecal BCFA composition between diarrheic and nondiarrheic dairy calves, and (3) explore the potential relationships between BCFA and microbiota in the feces. A total of 32 male Holstein dairy calves (13 ± 3 d old) with the same diet management were grouped as diarrheic (n = 16) or healthy (n = 16) based on fecal score (determined by liquid fecal consistency with some solid particles); diarrhea cases were defined as fecal score ≥2 for at least 2 d. Fecal samples were collected on the seventh day after calf arrival, and the fecal BCFA and microbial profiles were assessed using gas chromatograph and amplicon sequencing, respectively. In total, 7 BCFA were detected in the feces of all dairy calves; however, the concentrations of fecal BCFA differed between diarrheic and nondiarrheic calves. Specifically, the concentrations of iso-C16:0, iso-C17:0, anteiso-C17:0, and total even-chain BCFA were significantly higher in the feces of diarrheic calves. When the associations between BCFA and bacteria were studied, the relative abundance of Eggerthella was positively correlated with the concentrations of iso-C16:0 (ρ = 0.67), iso-17:0 (ρ = 0.77), anteiso-C17:0 (ρ = 0.73), and iso-C18:0 (ρ = 0.65), whereas the relative abundance of Subdoligranulum was positively correlated with the concentrations of iso-C14:0 (ρ = 0.62), iso-C15:0 (ρ = 0.78), and anteiso-C15:0 (ρ = 0.63). Use of random forest algorithm showed that BCFA such as anteiso-C15:0, iso-C16:0, iso-C17:0, iso-C18:0, and total even-chain BCFA could be used as biomarkers to differentiate diarrheic calves from healthy ones. Our findings generated fundamental knowledge on the potential roles of BCFA in neonatal calf gut health. Follow-up studies with larger animal populations are warranted to validate the feasibility of using BCFA as indicators of health status in neonatal calves.


Assuntos
Doenças dos Bovinos/metabolismo , Diarreia/veterinária , Ácidos Graxos/análise , Fezes/química , Fezes/microbiologia , Microbioma Gastrointestinal , Animais , Animais Recém-Nascidos , Bovinos , Doenças dos Bovinos/microbiologia , Diarreia/microbiologia , Feminino , Nível de Saúde
6.
Trop Anim Health Prod ; 53(1): 50, 2020 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-33369699

RESUMO

The aim of this study was to characterize the colostrum and fecal microbiota in calves and to investigate whether fecal microbiota composition was related to colostrum microbiota or factors associated with calf health. Colostrum samples were collected in buckets after hand milking of 76 calving cows from 38 smallholder dairy farms. Fecal samples were taken directly from the rectum of 76 calves at birth and at 14 days age. The bacterial community structure in colostrum and feces was analyzed by terminal restriction fragment length polymorphism for all samples, and the microbial composition was determined by 16S rRNA gene amplicon sequencing for a subset of the samples (8 colostrum, 40 fecal samples). There was a significant difference in fecal microbiota composition between day 0 and day 14 samples, but no associations between the microbiota and average daily gain, birth weight, or transfer of passive immunity. At 14 days of age, Faecalibacterium and Butyricicoccus were prevalent in higher relative abundances in the gut of healthy calves compared to calves with diarrhea that had been treated with antimicrobials. Colostrum showed great variation in composition of microbiota but no association to fecal microbiota. This study provides the first insights into the composition of colostrum and fecal microbiota of young dairy calves in southern Vietnam and can form the basis for future more detailed studies.


Assuntos
Bactérias/classificação , Bovinos/microbiologia , Colostro/microbiologia , Fezes/microbiologia , Microbioma Gastrointestinal , Animais , Animais Recém-Nascidos , Bactérias/isolamento & purificação , Doenças dos Bovinos/microbiologia , Diarreia/microbiologia , Diarreia/veterinária , Feminino , Masculino , Microbiota , Leite , Gravidez , RNA Bacteriano/análise , RNA Ribossômico 16S/análise , Vietnã
7.
PLoS One ; 15(9): e0239260, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32931511

RESUMO

Coxiella burnetii is a highly infectious zoonotic pathogen infecting wide range of mammals, including humans. In the present study, a total of 711 blood samples from bovines [cattle (n = 543) and buffaloes (n = 168)] from eight farms at different geographical locations in India were screened for C. burnetii targeting the IS1111 and the com1 genes. The anti-C. burnetii antibodies in serum samples were detected using indirect-ELISA kits. Also, a total of 21 parameters pertaining to animal health and farm management were identified to assess their role as possible risk factors for coxiellosis among the targeted farms. The apparent prevalence (positive for PCR and/or ELISA) for coxiellosis was reported to be 24.5% in cattle and 8.9% in buffaloes. In cattle, the detection rate of C. burnetii employing the IS1111 gene (8.5%) was found to be significantly higher (p<0.05) as compared to the com1 (6.5%) gene. The seropositivity by ELISA was higher among cattle (17.7%) than in buffaloes (8.3%). Further, on univariable analysis of risk factors, species (cattle) (OR:3.31; 95%CI:1.88-5.82), inadequate floor spacing (OR:1.64; 95%CI:1.10-2.43), mastitis (OR:2.35, 95%CI:1.45-3.81) and reproductive disorders (OR:2.54; 95%CI:1.67-3.85) were significantly (p<0.05) having high odds for coxiellosis. The multivariable logistic regression analysis of the animal level risk factors revealed that species and age were found to be significantly associated with coxiellosis. However, since the number of screened farms is limited; further research is needed with a higher number of animals to confirm the farm level odds ratio of risk factors. Quarantine and biosecurity measures including farm hygiene operations were observed to be inadequate and also the lack of awareness about coxiellosis among the farm workers. In absence of vaccination program for coxiellosis in India, robust surveillance, farm biosecurity measures and the awareness for the disease among risk groups can play an important role in the disease prevention and subsequent transmission of the pathogen.


Assuntos
Anticorpos Antibacterianos/sangue , Doenças dos Bovinos/sangue , Coxiella burnetii/genética , Febre Q/sangue , Animais , Bovinos , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/microbiologia , Coxiella burnetii/patogenicidade , Ensaio de Imunoadsorção Enzimática , Fazendeiros , Feminino , Humanos , Índia/epidemiologia , Leite/microbiologia , Reação em Cadeia da Polimerase , Febre Q/genética , Febre Q/microbiologia , Zoonoses/sangue , Zoonoses/genética , Zoonoses/microbiologia
8.
PLoS One ; 15(9): e0239135, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32931522

RESUMO

The rising public health threat of antimicrobial resistance, the influence of food service companies, as well as the overall lack of positive image of using medical products in intensive farming are major drivers curbing antimicrobial use. In the future, government policies may affect practices of antimicrobial use in beef production in feedlots, a prominent current user of antimicrobials in animal agriculture, but also the agricultural industry generating the highest cash receipt in the U.S. Our objective was to estimate the cost effect from the following policies in feedlots: 1) using antimicrobials for disease prevention, control, and treatment; 2) using antimicrobials only for treatment of disease; and 3) not using antimicrobials for any reason. We modelled a typical U.S. feedlot, where high risk cattle may be afflicted by diseases requiring antimicrobial therapy, namely respiratory diseases, liver abscesses and lameness. We calculated the net revenue loss under each policy of antimicrobial use restriction. With moderate disease incidence, the median net revenue loss was $66 and $96 per animal entering the feedlot, for not using antimicrobials for disease prevention and control, or not using any antimicrobials, respectively, compared to using antimicrobials for disease prevention, control, and treatment. Losses arose mainly from an increase of fatality and morbidity rates, almost doubling for respiratory diseases in the case of antimicrobial use restrictions. In the case of antimicrobial use prohibition, decreasing the feeder cattle price by 9%, or alternatively, increasing the slaughter cattle price by 6.3%, would offset the net revenue losses for the feedlot operator. If no alternatives to antimicrobial therapy for prevention, control and treatment of current infectious diseases are implemented, policies that economically incentivize adoption of non-antimicrobial prevention and control strategies for infectious diseases would be necessary to maintain animal welfare and the profitability of beef production while simultaneously curbing antimicrobial use.


Assuntos
Criação de Animais Domésticos/economia , Antibacterianos/normas , Doenças dos Bovinos/tratamento farmacológico , Fazendas/economia , Políticas , Criação de Animais Domésticos/normas , Bem-Estar do Animal/economia , Bem-Estar do Animal/normas , Animais , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Bovinos , Doenças dos Bovinos/economia , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/microbiologia , Simulação por Computador , Efeitos Psicossociais da Doença , Análise Custo-Benefício , Farmacorresistência Bacteriana , Fazendas/normas , Incidência , Modelos Econômicos , Carne Vermelha/economia
9.
Benef Microbes ; 11(5): 477-488, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32877228

RESUMO

Neonatal calf diarrhoea is one of the challenges faced by intensive farming, and probiotics are considered a promising approach to improve calves' health. The objective of this study was to evaluate the effect of potential probiotic lactobacilli on new-born dairy calves' growth, diarrhoea incidence, faecal score, cytokine expression in blood cells, immunoglobulin A (IgA) levels in plasma and faeces, and pathogen abundance in faeces. Two in vivo assays were conducted at the same farm in two annual calving seasons. Treated calves received one daily dose of the selected lactobacilli (Lactobacillus reuteri TP1.3B or Lactobacillus johnsonii TP1.6) for 10 consecutive days. A faecal score was recorded daily, average daily gain (ADG) was calculated, and blood and faeces samples were collected. Pathogen abundance was analysed by absolute qPCR in faeces using primers directed at Salmonella enterica, rotavirus, coronavirus, Cryptosporidium parvum and three Escherichia coli virulence genes (eae, clpG and Stx1). The faecal score was positively affected by the administration of both lactobacilli strains, and diarrhoea incidence was significantly lower in treated calves. No differences were found regarding ADG, cytokine expression, IgA levels and pathogen abundance. Our findings showed that oral administration of these strains could improve gastrointestinal health, but results could vary depending on the calving season, which may be related to pathogen seasonality and other environmental effects.


Assuntos
Doenças dos Bovinos/terapia , Diarreia , Lactobacillus johnsonii/metabolismo , Lactobacillus reuteri/metabolismo , Probióticos/uso terapêutico , Animais , Animais Recém-Nascidos , Bovinos , Doenças dos Bovinos/microbiologia , Doenças dos Bovinos/prevenção & controle , Infecções por Coronavirus/prevenção & controle , Infecções por Coronavirus/veterinária , Criptosporidiose/prevenção & controle , Citocinas/sangue , Indústria de Laticínios , Diarreia/prevenção & controle , Diarreia/terapia , Diarreia/veterinária , Infecções por Escherichia coli/prevenção & controle , Infecções por Escherichia coli/veterinária , Fezes/virologia , Trato Gastrointestinal/microbiologia , Imunoglobulina A/sangue , Infecções por Rotavirus/prevenção & controle , Infecções por Rotavirus/veterinária , Salmonelose Animal/prevenção & controle
10.
Vet Parasitol Reg Stud Reports ; 21: 100435, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32862896

RESUMO

Faecal specimens from 36 scouring neonatal calves from two dairy farms located in the Al Ain region of the UAE were screened with pathogen-specific antigen ELISA for Cryptosporidium parvum, Escherichia coli K99, rotavirus, and coronavirus. Additionally, faecal smears were stained with modified-acid-fast for Cryptosporidium oocysts, and the VITEK 2 system plus Gram's stain used to identify bacteria isolated from the faecal samples. Farm management practices were also evaluated during a farm visit. Of the 36 calves, 29, 13, 5, and 6 were positive for C. parvum, E. coli K99, bovine coronavirus, and rotavirus antigens respectively, while 27 were positive for Cryptosporidium oocysts. In various combinations, mixed infections were detected in 20/36 calves. This is the first report of C. parvum, E. coli K99, Salmonella spp., rotavirus, and coronavirus in ≤14-days-old scouring neonatal dairy calves from the UAE. Molecular characterization of these pathogens and nationwide epidemiological calf scour studies are recommended.


Assuntos
Doenças dos Bovinos/epidemiologia , Criptosporidiose/epidemiologia , Cryptosporidium parvum , Animais , Animais Recém-Nascidos/microbiologia , Animais Recém-Nascidos/parasitologia , Bovinos , Doenças dos Bovinos/microbiologia , Doenças dos Bovinos/parasitologia , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/veterinária , Coronavirus Bovino , Indústria de Laticínios , Infecções por Escherichia coli/epidemiologia , Infecções por Escherichia coli/microbiologia , Infecções por Escherichia coli/veterinária , Feminino , Masculino , Infecções por Rotavirus/epidemiologia , Infecções por Rotavirus/veterinária , Salmonelose Animal/epidemiologia , Emirados Árabes Unidos/epidemiologia
11.
PLoS One ; 15(8): e0228366, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32866142

RESUMO

The role of questing ticks in the epidemiology of tick-borne diseases in Kenya's Maasai Mara National Reserve (MMNR), an ecosystem with intensified human-wildlife-livestock interactions, remains poorly understood. We surveyed the diversity of questing ticks, their blood-meal hosts, and tick-borne pathogens to understand potential effects on human and livestock health. By flagging and hand-picking from vegetation in 25 localities, we collected 1,465 host-seeking ticks, mostly Rhipicephalus and Amblyomma species identified by morphology and molecular analysis. We used PCR with high-resolution melting (HRM) analysis and sequencing to identify Anaplasma, Babesia, Coxiella, Ehrlichia, Rickettsia, and Theileria pathogens and blood-meal remnants in 231 tick pools. We detected blood-meals from humans, wildebeest, and African buffalo in Rh. appendiculatus, goat in Rh. evertsi, sheep in Am. gemma, and cattle in Am. variegatum. Rickettsia africae was detected in Am. gemma (MIR = 3.10) that had fed on sheep and in Am. variegatum (MIR = 250) that had fed on cattle. We found Rickettsia spp. in Am. gemma (MIR = 9.29) and Rh. evertsi (MIR = 200), Anaplasma ovis in Rh. appendiculatus (MIR = 0.89) and Rh. evertsi (MIR = 200), Anaplasma bovis in Rh. appendiculatus (MIR = 0.89), and Theileria parva in Rh. appendiculatus (MIR = 24). No Babesia, Ehrlichia, or Coxiella pathogens were detected. Unexpectedly, species-specific Coxiella sp. endosymbionts were detected in all tick genera (174/231 pools), which may affect tick physiology and vector competence. These findings show that ticks from the MMNR are infected with zoonotic R. africae and unclassified Rickettsia spp., demonstrating risk of African tick-bite fever and other spotted-fever group rickettsioses to locals and visitors. The protozoan pathogens identified may also pose risk to livestock production. The diverse vertebrate blood-meals of questing ticks in this ecosystem including humans, wildlife, and domestic animals, may amplify transmission of tick-borne zoonoses and livestock diseases.


Assuntos
Infestações por Carrapato/epidemiologia , Doenças Transmitidas por Carrapatos/epidemiologia , Carrapatos/patogenicidade , Animais , Animais Selvagens , Babesia , Bovinos , Doenças dos Bovinos/microbiologia , Coxiella , Ecossistema , Ehrlichia , Humanos , Ixodidae/microbiologia , Quênia/epidemiologia , Rhipicephalus , Rickettsia , Ovinos , Theileria , Infestações por Carrapato/veterinária , Doenças Transmitidas por Carrapatos/microbiologia , Carrapatos/parasitologia , Zoonoses
12.
Int J Food Microbiol ; 334: 108828, 2020 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-32866940

RESUMO

Raw milk is a continued threat to public health due to possible contamination with zoonotic pathogens. Enterocytozoon bieneusi is one of the most prevalent pathogenic fungi in a wide range of vertebrate hosts, causing diarrheal disease. Although there has been some evidence, the role and potential risk of raw milk of dairy animals in the transmission dynamics of E. bieneusi is not clear. Therefore, we aimed to determine the occurrence and genotypes of E. bieneusi in raw milk of dairy animals in several farms of the Central Anatolia Region. We also investigated if there is a relation between the presence of E. bieneusi and mastitis. Genomic DNAs from a total of 450 raw milk including 200, 200 and 50 samples from cattle, sheep and water buffalo respectively were analyzed using nested PCR, targeting the internal transcribed spacer of E. bieneusi. Totally milk samples of 9 (4.5%) dairy cattle, 36 (18.0%) sheep, and 1 (2.0%) water buffalo were PCR-positive. A significant relationship was determined between mastitis and the presence of E. bieneusi. Sequence analysis revealed the presence of eight genotypes: two known (ERUSS1, BEB6) and six novel genotypes (named as TREb1 to TREb6). The genotype ERUSS1 and BEB6 were the most common genotypes, found in all cattle and sheep farms. Phylogenetic analysis clustered all the identified genotypes in Group 2. This study provides novel findings that contribute to the transmission dynamics and molecular epidemiology of E. bieneusi. Our study also highlighted the potential risk of raw milk for public health with respect to microsporidia infections.


Assuntos
Doenças dos Bovinos/epidemiologia , Enterocytozoon/genética , Microsporidiose/veterinária , Leite/microbiologia , Doenças dos Ovinos/epidemiologia , Animais , Búfalos , Bovinos , Doenças dos Bovinos/microbiologia , Doenças dos Bovinos/transmissão , Enterocytozoon/classificação , Enterocytozoon/isolamento & purificação , Fazendas , Feminino , Genótipo , Mastite/epidemiologia , Mastite/microbiologia , Mastite/veterinária , Microsporidiose/epidemiologia , Microsporidiose/microbiologia , Microsporidiose/transmissão , Epidemiologia Molecular , Filogenia , Prevalência , Ovinos , Doenças dos Ovinos/microbiologia , Doenças dos Ovinos/transmissão , Turquia
13.
J Anim Sci ; 98(8)2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32761212

RESUMO

Acute and subacute ruminal acidosis (SARA) are common nutritional problems in both beef and dairy cattle. Therefore, the objective of this review is to describe how ruminal Gram-negative bacteria could contribute to the pathogenesis of ruminal acidoses, by releasing lipopolysaccharides (LPS; a component of their cell wall) in the ruminal fluid. When cattle consume excessive amounts of highly fermentable carbohydrates without prior adaptation, normal fermentation become disrupted. The fermentation of these carbohydrates quickly decreases ruminal pH due to the accumulation of short-chain fatty acids and lactate in the rumen. As a consequence, ruminal epithelium may be damaged and tissue function could be impaired, leading to a possible translocation of pathogenic substances from the rumen into the bloodstream. Such changes in fermentation are followed by an increase in Gram-positive bacteria while Gram-negative bacteria decrease. The lyses of Gram-negative bacteria during ruminal acidosis increase LPS concentration in the ruminal fluid. Because LPS is a highly proinflammatory endotoxin in the circulatory system, past studies have raised concerns regarding ruminal LPS contribution to the pathogenesis of ruminal acidosis. Although animals that undergo these disorders do not always have an immune response, recent studies showed that different Gram-negative bacteria have different LPS composition and toxicity, which may explain the differences in immune response. Given the diversity of Gram-negative bacteria in the rumen, evaluating the changes in the bacterial community during ruminal acidosis could be used as a way to identify which Gram-negative bacteria are associated with LPS release in the rumen. By identifying and targeting ruminal bacteria with possible pathogenic LPS, nutritional strategies could be created to overcome, or at least minimize, ruminal acidosis.


Assuntos
Acidose/veterinária , Doenças dos Bovinos/microbiologia , Bactérias Gram-Negativas/metabolismo , Lipopolissacarídeos/metabolismo , Acidose/microbiologia , Animais , Bovinos , Dieta/veterinária , Epitélio/metabolismo , Epitélio/microbiologia , Ácidos Graxos Voláteis/metabolismo , Fermentação , Concentração de Íons de Hidrogênio , Lipopolissacarídeos/efeitos adversos , Rúmen/metabolismo , Rúmen/microbiologia
14.
Acta Vet Scand ; 62(1): 45, 2020 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-32819409

RESUMO

BACKGROUND: Escherichia coli is an important cause of diarrhea in calves and its diarrheagenic properties are related to presence of certain virulence genes. In this study, the prevalence of virulence genes F5, F17, F41, sta, stx1, stx2, eae, and saa in E. coli isolated from pre-weaned calves presenting with (n= 329) or without diarrhea (n= 360) was explored using multiplex polymerase chain reaction. We also evaluated the association between detection of E. coli and the presence of diarrhea. RESULTS: Escherichia coli was detected in 56.3% (388/689) of the fecal samples and showed the highest prevalence (66.5%) in 21-40-day-old calves and the lowest (46.3%) among those that were 1-20 days old. The prevalence of the enterotoxigenic E. coli (ETEC) and Shiga toxin-producing E. coli (STEC) pathotypes was detected in 73.9% and 15.9%, respectively. The results showed no association between diarrhea and the presence of E. coli in general, ETEC or STEC. The F17 gene was the most frequently detected virulence factor in E. coli of calves of all ages regardless of diarrhea. Interestingly, the results show that the calves aged 41-60 days with F17-positive E. coli are at a higher risk for production of Shiga toxin (Stx1; 95% confidence intervals: 1.86-31.95; P = 0.005) compared to calves aged 1-20 days; no association between this finding and diarrhea was observed among the calves of this age group. Moreover, the virulence genes associated with the ETEC and STEC strains were not significantly associated with pathogenicity in this study cohort. CONCLUSIONS: These results suggest that while the incidence of E. coli is age-related, there was no relationship linking E. coli virulence genes to calf age and diarrhea. Furthermore, the present study demonstrated that detection of E. coli strains either with or without virulence factors was not associated with diarrhea in pre-weaned calves.


Assuntos
Doenças dos Bovinos/epidemiologia , Diarreia/veterinária , Infecções por Escherichia coli/veterinária , Proteínas de Escherichia coli/genética , Escherichia coli/genética , Fatores de Virulência/genética , Animais , Bovinos , Doenças dos Bovinos/microbiologia , Diarreia/epidemiologia , Diarreia/microbiologia , Escherichia coli/patogenicidade , Infecções por Escherichia coli/epidemiologia , Infecções por Escherichia coli/microbiologia , Proteínas de Escherichia coli/metabolismo , Prevalência , República da Coreia/epidemiologia , Virulência/genética , Fatores de Virulência/metabolismo
15.
J S Afr Vet Assoc ; 91(0): e1-e11, 2020 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-32787418

RESUMO

This study investigated the occurrence and phylogenetic relationship of protozoan parasites and Ehrlichia infecting domestic animals from three municipalities in uMkhanyakude district of KwaZulu-Natal province, South Africa. A total of 208 blood samples collected from clinically healthy cattle, sheep, goats and dogs from uMkhanyakude district were examined by polymerase chain reaction (PCR) assays, using either genus or species-specific primers to determine the occurrence and phylogenetic relationship of various protozoan parasites and Ehrlichia of veterinary importance. A total of 5/109 (4.6%) cattle were PCR-positive for the presence of Toxoplasma gondii, 33/109 (30.3%) for Babesia bovis, 24/109 (22.02%) for Babesia bigemina and 20/109 (18.3%) for Trypanosoma sp., while 3/10 (30%) of sheep were PCR-positive for Theileria ovis and none of the goats were positive for any of the detected pathogens. The co-infection of 4/109 (3.7%) B. bovis and B. bigemina was detected in cattle. Only Ehrlichia canis was detected in dogs with infection rate of 20/48 (41.7%). Sequences of PCR-positive isolates (B. bovis, B. bigemina, E. canis, T. ovis and T. gondii) showed that they were closely related to their relevant species from various countries. These findings have expanded our knowledge about the prevalence and phylogenetic similarity between protozoan parasites and Ehrlichia isolates of South African origin. To date, this is the first study in South Africa to detect T. gondii infections from cattle blood using PCR.


Assuntos
Babesiose/parasitologia , Coinfecção/veterinária , Ehrlichiose/veterinária , Theileriose/parasitologia , Toxoplasmose Animal/parasitologia , Tripanossomíase/veterinária , Animais , Babesia/classificação , Babesia/isolamento & purificação , Babesiose/microbiologia , Bovinos , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/microbiologia , Doenças dos Bovinos/parasitologia , Coinfecção/microbiologia , Coinfecção/parasitologia , Doenças do Cão/epidemiologia , Doenças do Cão/microbiologia , Doenças do Cão/parasitologia , Cães , Ehrlichia canis/isolamento & purificação , Ehrlichiose/microbiologia , Ehrlichiose/parasitologia , Doenças das Cabras/epidemiologia , Doenças das Cabras/microbiologia , Doenças das Cabras/parasitologia , Cabras , Prevalência , Ovinos , Doenças dos Ovinos/epidemiologia , Doenças dos Ovinos/microbiologia , Doenças dos Ovinos/parasitologia , África do Sul/epidemiologia , Theileria/isolamento & purificação , Theileriose/microbiologia , Toxoplasma/isolamento & purificação , Toxoplasmose Animal/microbiologia , Trypanosoma/classificação , Trypanosoma/isolamento & purificação , Tripanossomíase/microbiologia , Tripanossomíase/parasitologia
16.
J Vet Sci ; 21(4): e54, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32735092

RESUMO

BACKGROUND: Methicillin-resistant Staphylococcus aureus (MRSA) is a leading cause of severe infections in humans and animals worldwide. Studies elucidating the population structure, staphylococcal cassette chromosome mec types, resistance phenotypes, and virulence gene profiles of animal-associated MRSA are needed to understand spread and transmission. OBJECTIVES: The objective of this study was to determine 1) clonal complexes and spa types, 2) resistance phenotypes, and 3) virulence/resistance gene profiles of MRSA isolated from animals in Switzerland. METHODS: We analyzed 31 presumptive MRSA isolates collected from clinical infections in horses, dogs, cattle, sheep, and pigs, which had tested positive in the Staphaurex Latex Agglutination Test. The isolates were characterized by spa typing and DNA microarray profiling. In addition, we performed antimicrobial susceptibility testing using the VITEK 2 Compact system. RESULTS: Characterization of the 31 presumptive MRSA isolates revealed 3 methicillin-resistant Staphylococcus pseudintermedius isolates, which were able to grow on MRSA2 Brilliance agar. Of the 28 MRSA isolates, the majority was assigned to CC398 (86%), but CC8 (11%) and CC1 (4%) were also detected. The predominant spa type was t011 (n = 23), followed by t009 (n = 2), t034 (n = 1), t008 (n = 1), and t127 (n = 1). CONCLUSIONS: The results of this study extend the current body of knowledge on the population structure, resistance phenotypes, and virulence and resistance gene profiles of MRSA from livestock and companion animals.


Assuntos
Resistência Microbiana a Medicamentos/genética , Staphylococcus aureus Resistente à Meticilina/genética , Análise de Sequência com Séries de Oligonucleotídeos/veterinária , Infecções Estafilocócicas/veterinária , Animais , Bovinos , Doenças dos Bovinos/microbiologia , Doenças do Cão/microbiologia , Cães , Doenças dos Cavalos/microbiologia , Cavalos , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Fenótipo , Ovinos , Doenças dos Ovinos/microbiologia , Infecções Estafilocócicas/microbiologia , Suínos , Doenças dos Suínos/microbiologia
17.
Exp Parasitol ; 217: 107958, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32730769

RESUMO

Anaplasma marginale is the causative agent of the severe bovine anaplasmosis. The tick Rhipicephalus microplus is one of the main vectors of A. marginale in tropical and subtropical regions of the world. After the tick bite, the bacterium invades and proliferates within the bovine erythrocytes leading to anemia, impairment of milk production and weight loss. In addition, infection can cause abortion and high mortality in areas of enzootic instability. Immunization with live and inactivated vaccines are employed to control acute bovine anaplasmosis. However, they do not prevent persistent infection. Consequently, infected animals, even if immunized, are still reservoirs of the bacterium and contribute to its dissemination. Antimicrobials are largely employed for the prophylaxis of bovine anaplasmosis. However, they are often used in sublethal doses which may select pre-existing resistant bacteria and induce genetic or phenotypic variations. Therefore, we propose a new standardized in vitro assay to evaluate the susceptibility of A. marginale strains to different antimicrobials. This tool will help health professionals to choose the more adequate treatment for each herd which will prevent the selection and spread of resistant strains. For that, we initially evaluated the antimicrobial susceptibility of two field isolates of A. marginale (Jaboticabal and Palmeira) infecting bovines. The least susceptible strain (Jaboticabal) was used for the standardization of an antimicrobial assay using a culture of Ixodes scapularis-derived tick cell line, ISE6. Results showed that enrofloxacin (ENRO) at 0.25, 1 or 4 µg/mL and oxytetracycline (OTC) at 4 or 16 µg/mL are the most efficient treatments, followed by OTC at 1 µg/mL and imidocarb dipropionate (IMD) at 1 or 4 µg/mL. In addition, this proposed tool has technical advantages compared to the previously established bovine erythrocyte culture. Thereby, it may be used to guide cattle farmers to the correct use of antimicrobials. The choice of the most suitable antimicrobial is essential to eliminate persistent infections, prevent the spread of resistant strains and help controlling of bovine anaplasmosis.


Assuntos
Anaplasma marginale/efeitos dos fármacos , Anaplasmose/prevenção & controle , Antibacterianos/farmacologia , Vetores Aracnídeos/citologia , Doenças dos Bovinos/prevenção & controle , Rhipicephalus/citologia , Anaplasmose/tratamento farmacológico , Anaplasmose/microbiologia , Animais , Antibacterianos/uso terapêutico , Vetores Aracnídeos/parasitologia , Brasil , Bovinos , Doenças dos Bovinos/tratamento farmacológico , Doenças dos Bovinos/microbiologia , Linhagem Celular , Enrofloxacina/farmacologia , Eritrócitos/microbiologia , Imidocarbo/análogos & derivados , Imidocarbo/farmacologia , Imidocarbo/uso terapêutico , Masculino , Testes de Sensibilidade Microbiana , Oxitetraciclina/farmacologia , Oxitetraciclina/uso terapêutico , Reação em Cadeia da Polimerase em Tempo Real , Rhipicephalus/parasitologia
18.
PLoS Negl Trop Dis ; 14(7): e0008461, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32706772

RESUMO

Brucellosis is a bacterial zoonotic disease that has important veterinary and public health consequences as well as economic impact in sub Saharan Africa including Ethiopia. A cross-sectional study was conducted in four selected districts of Borena Pastoral setting in Southern Ethiopia from October 2017 to February 2018 to estimate the prevalence of brucellosis and assess associated risk factors in cattle, sheep, goats and occupationally associated humans. A total of 750 cattle, 882 sheep and goats and 341 human subjects were screened for evidence of brucellosis using the Rose Bengal Test (RBT) with positive results confirmed by Competitive-ELISA(c-ELISA). Structured questionnaires were used for collection of metadata from individual animals, herders and animal attendants to test the association between explanatory and outcome variables. The overall animal level prevalence was 2.4% (95% confidence interval, CI: 1.4-3.7) in cattle, 3.2% (95% CI: 2.1-4.6) in sheep and goats, and 2.6% (95% CI: 1.2-5) in humans occupationally linked to livestock production systems. Herd size, parity, and history of abortion were risk factors associated with Brucella seropositivity (P<0.05) in cattle whereas in sheep and goats the results showed that district, age group, flock size, and history of abortion were significantly associated risk factors with Brucella seropositivity (P<0.05). Assisting calving and presence of seropositive animals in a household (P<0.05) were significantly associated with Brucella seropositivity in humans. Evidence of brucellosis in various animal species and the associated human population illustrates the need for a coordinated One Health approach to controlling brucellosis so as to improve public health and livestock productivity.


Assuntos
Brucelose/veterinária , Doenças dos Bovinos/microbiologia , Doenças das Cabras/microbiologia , Doenças dos Ovinos/microbiologia , Animais , Brucelose/epidemiologia , Bovinos , Doenças dos Bovinos/epidemiologia , Etiópia/epidemiologia , Doenças das Cabras/epidemiologia , Cabras , Humanos , Prevalência , Fatores de Risco , Ovinos , Doenças dos Ovinos/epidemiologia , Zoonoses
19.
BMC Vet Res ; 16(1): 264, 2020 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-32727468

RESUMO

BACKGROUND: Neonatal diarrhea remains one of the main causes of morbi-mortality in dairy calves under artificial rearing. It is often caused by infectious agents of viral, bacterial, or parasitic origin. Cows vaccination and colostrum intake by calves during the first 6 h of life are critical strategies to prevent severe diarrhea but these are still insufficient. Here we report the field evaluation of a product based on IgY antibodies against group A rotavirus (RVA), coronavirus (CoV), enterotoxigenic Escherichia coli, and Salmonella sp. This product, named IgY DNT, has been designed as a complementary passive immunization strategy to prevent neonatal calf diarrhea. The quality of the product depends on the titers of specific IgY antibodies to each antigen evaluated by ELISA. In the case of the viral antigens, ELISA antibody (Ab) titers are correlated with protection against infection in calves experimentally challenged with RVA and CoV (Bok M, et al., Passive immunity to control bovine coronavirus diarrhea in a dairy herd in Argentina, 2017), (Vega C, et al., Vet Immunol Immunopathol, 142:156-69, 2011), (Vega C, et al., Res Vet Sci, 103:1-10, 2015). To evaluate the efficiency in dairy farms, thirty newborn Holstein calves were randomly assigned to IgY DNT or control groups and treatment initiated after colostrum intake and gut closure. Calves in the IgY DNT group received 20 g of the oral passive treatment in 2 L of milk twice a day during the first 2 weeks of life. Animals were followed until 3 weeks of age and diarrhea due to natural exposure to infectious agents was recorded during all the experimental time. RESULTS: Results demonstrate that the oral administration of IgY DNT during the first 2 weeks of life to newborn calves caused a delay in diarrhea onset and significantly reduced its severity and duration compared with untreated calves. Animals treated with IgY DNT showed a trend towards a delay in RVA infection with significantly shorter duration and virus shedding compared to control calves. CONCLUSIONS: This indicates that IgY DNT is an effective product to complement current preventive strategies against neonatal calf diarrhea in dairy farms. Furthermore, to our knowledge, this is the only biological product available for the prevention of virus-associated neonatal calf diarrhea.


Assuntos
Anticorpos Antibacterianos/uso terapêutico , Anticorpos Antivirais/uso terapêutico , Doenças dos Bovinos/terapia , Diarreia/veterinária , Imunoglobulinas/uso terapêutico , Imunoterapia , Animais , Animais Recém-Nascidos , Anticorpos Antiprotozoários , Bovinos , Doenças dos Bovinos/microbiologia , Doenças dos Bovinos/virologia , Criptosporidiose/prevenção & controle , Indústria de Laticínios , Diarreia/microbiologia , Diarreia/terapia , Diarreia/virologia , Imunização Passiva/métodos , Imunização Passiva/veterinária
20.
PLoS One ; 15(7): e0235862, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32645099

RESUMO

Brucellosis is an endemic disease in food-producing animals in Mosul, Iraq. The objectives of the study reported here were: (i) to identify and assess the evidence and knowledge gaps in published studies that have examined brucellosis in different food-producing animals in Mosul, Iraq; using systematic review approach, and (ii) to quantify the seroprevalence of brucellosis in the city using meta-analysis approach. Google Scholar was used as a search engine to track pertinent peer-reviewed research reports. The search was conducted on November 24, 2019. Keywords used were: brucella, animal, Mosul, Iraq. Peer-reviewed published studies, MSc theses, and PhD dissertations written in Arabic or English were included. Duplicate records were removed, and the screening process was conducted at three levels: titles, abstracts, and full-text articles. Identified studies that have reported the seroprevalence of brucellosis were included in a meta-analysis to calculate an overall prevalence. A total of 214 records were initially identified. Seventeen research reports were added from personal contact and qualified articles' references list. Thirty six articles were qualified for review after removing 35 duplicate records, 155 titles, 11 abstracts, and 5 full text articles. Seventeen studies reported the prevalence of brucellosis, 11 studies assessed different serological tests for diagnosis of brucellosis, 9 studies isolated Brucella spp. from animal specimens and/or animal products, and 4 studies assessed vaccination procedures against brucellosis. The overall seroprevalence of brucellosis in food-producing animals in Mosul over a period of 40 years was 14.14%, including 14.46% for sheep, 12.99% for goats, 11.69% for cattle, and 22.64% for buffalo. The study concluded that the disease is evident in the city with increasing trends over the years, buffalo shows high seroprevalence, the degree of agreement of Rose-Bengal test as a screening test is fair compared to more accurate serological tests such as ELISA; and the disease constitutes a public health concern in the city. Additional studies are important to identify the overlooked predisposing factors, estimate the abortion rate attributable to brucellosis in food-producing animals, and evaluate efficacy of vaccination programs in reducing the prevalence of brucellosis and/or abortion rate.


Assuntos
Brucelose/veterinária , Doenças dos Bovinos/epidemiologia , Doenças das Cabras/epidemiologia , Doenças dos Ovinos/epidemiologia , Animais , Brucella/isolamento & purificação , Brucelose/epidemiologia , Búfalos , Bovinos , Doenças dos Bovinos/microbiologia , Doenças das Cabras/microbiologia , Cabras , Humanos , Iraque/epidemiologia , Estudos Soroepidemiológicos , Ovinos , Doenças dos Ovinos/microbiologia
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