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1.
Parasitol Int ; 74: 101925, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31077806

RESUMO

Tick-borne diseases cause significant losses to livestock production in tropical and subtropical regions. However, information about the tick-borne infections in cattle in Xinjiang Uygur Autonomous Region (XUAR), northwestern China, is scarce. In this study, nested polymerase chain reaction (PCR) assays and gene sequencing were used to detect and analyze epidemiological features of Babesia bovis, B. bigemina, Coxiella burnetii and Anaplasma bovis infections in XUAR. Out of 195 samples tested, 24 (12.3%), 67 (34.4%), 40 (20.5%) and 10 (5.1%) were positive for B. bovis, B. bigemina, C. burnetii and A. bovis, respectively. Sequencing analysis indicated that B. bovis SBP-4, B. bigemina Rap1a, C. burnetii htpB and A. bovis 16S rRNA genes from XUAR showed 99%-100% identity with documented isolates from other countries. Phylogenetic analyses revealed that B. bovis SBP-4, B. bigemina Rap1a, C. burnetii htpB and A. bovis 16S rRNA gene sequences clustered in the same clade with isolates from other countries. To the best of our knowledge, this is the first report of C. burnetii infection of cattle in XUAR. Furthermore, this study provides important data for understanding the distribution of tick-borne pathogens, and is expected to improve the approach for prevention and control of tick-borne diseases in China.


Assuntos
Anaplasma/isolamento & purificação , Babesia/isolamento & purificação , Doenças dos Bovinos/epidemiologia , Coxiella burnetii/isolamento & purificação , Febre Q/veterinária , Doenças Transmitidas por Carrapatos/veterinária , Anaplasma/genética , Anaplasmose/epidemiologia , Animais , Babesia/genética , Babesiose/epidemiologia , Bovinos , Doenças dos Bovinos/microbiologia , Doenças dos Bovinos/parasitologia , China/epidemiologia , Coxiella burnetii/genética , DNA Bacteriano/genética , DNA de Protozoário/genética , Filogenia , Febre Q/epidemiologia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Doenças Transmitidas por Carrapatos/epidemiologia , Carrapatos/microbiologia
2.
Theriogenology ; 141: 41-47, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31518727

RESUMO

Bovine leptospirosis is often associated with host-adapted leptospires infections, such as strains belonging to the Sejroe serogroup. Although bovine leptospirosis by adapted strains may result in abortions, fetal death, premature births and the birth of weak and/or low-weight calves, this infection is more closely associated with subtler syndromes, such as subfertility and early embryonic death. In this way, this silent disease can go unnoticed and undiagnosed, compromising reproductive efficiency with a consequent decrease in the productivity of herds over long periods. For many years, genital tract infection has been considered a secondary effect of renal infection with the assumption being that leptospires are found in the genital tract due to bacteremia caused by renal colonization. In contrast to this hypothesis, there is some evidence in the literature that suggests that genital leptospirosis should be considered a specific syndrome dissociated from renal/systemic disease. Therefore, this paper aims to gather and critically analyze information about genital leptospirosis in cattle, considering the disease a distinct syndrome, herein denominated bovine genital leptospirosis (BGL), that requires a unique approach to diagnosis and treatment.


Assuntos
Doenças dos Bovinos/microbiologia , Leptospirose/veterinária , Doenças Bacterianas Sexualmente Transmissíveis/veterinária , Aborto Animal/microbiologia , Animais , Bovinos , Doenças dos Bovinos/transmissão , Leptospira/classificação , Leptospira/fisiologia , Leptospirose/patologia , Leptospirose/transmissão , Doenças Bacterianas Sexualmente Transmissíveis/patologia
3.
Pol J Microbiol ; 68(3): 295-302, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31880874

RESUMO

The article presents data on serological studies of 573 sera samples of cattle that were collected from the farms affected by leptospirosis in different regions of Ukraine in the period of 2014-2015. Samples were investigated by the microscopic agglutination test (MAT), which was conducted within eight serological groups of Leptospira and nine serovars: Sejroe (serovars polonica and hardjo), Hebdomadis (serovar kabura), Tarassovi (serovar tarassovi), Pomona (serovar pomona), Grippotyphosa (serovar grippotyphosa), Canicola (serovar canicola), Icterohaemorrhagiae (serovar copenhageni), and Australis (serovar bratislava). The circulation of L. interrogans serovar hardjo among cattle has been observed in all 11 regions of Ukraine investigated within 25.8-60.0% of the leptospirosis-positive serum samples in these regions. Antibodies in the cattle sera against serovar hardjo (serogroup Sejroe) were detected in 139 of the 370 cows reacting positively in MAT. Overall, they were detected in 24.3% animals out of the total of 573 cows investigated. These are the preliminary results, however, in our opinion, they should allow to include the serovar hardjo in a standard panel of strains for MAT in Ukraine.The article presents data on serological studies of 573 sera samples of cattle that were collected from the farms affected by leptospirosis in different regions of Ukraine in the period of 2014­2015. Samples were investigated by the microscopic agglutination test (MAT), which was conducted within eight serological groups of Leptospira and nine serovars: Sejroe (serovars polonica and hardjo), Hebdomadis (serovar kabura), Tarassovi (serovar tarassovi), Pomona (serovar pomona), Grippotyphosa (serovar grippotyphosa), Canicola (serovar canicola), Icterohaemorrhagiae (serovar copenhageni), and Australis (serovar bratislava). The circulation of L. interrogans serovar hardjo among cattle has been observed in all 11 regions of Ukraine investigated within 25.8­60.0% of the leptospirosis-positive serum samples in these regions. Antibodies in the cattle sera against serovar hardjo (serogroup Sejroe) were detected in 139 of the 370 cows reacting positively in MAT. Overall, they were detected in 24.3% animals out of the total of 573 cows investigated. These are the preliminary results, however, in our opinion, they should allow to include the serovar hardjo in a standard panel of strains for MAT in Ukraine.


Assuntos
Anticorpos Antibacterianos/sangue , Doenças dos Bovinos/sangue , Leptospira interrogans/imunologia , Leptospirose/veterinária , Testes de Aglutinação , Animais , Bovinos , Doenças dos Bovinos/microbiologia , Feminino , Leptospira interrogans/classificação , Leptospira interrogans/genética , Leptospira interrogans/isolamento & purificação , Leptospirose/sangue , Leptospirose/microbiologia , Masculino , Sorogrupo , Ucrânia
4.
Res Vet Sci ; 127: 27-32, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31670090

RESUMO

Bovines are the primary reservoir of enterohemorrhagic Escherichia coli (EHEC) O157:H7 and the main source of its transmission to humans. Here, we present a one-year longitudinal study of fecal shedding of E. coli O157. E. coli O157 obtained from recto-anal mucosal samples were characterized by multiplex PCR. The E. coli O157 prevalence ranged from 0.84% in July to 15.25% in November. The confinement within pens resulted in prevalence of 11%. Most animals (61.86%; 75/118) shed E. coli O157 at least in one sampling occasion. Of the positive animals, 82.19%, 16.44%, and 1.37% were stx positive on one, two and three sampling occasions, respectively. All the E. coli O157 isolated strains carried the genes eae and rfbO157, whereas 11%, 33% and 56% contained stx1, stx2 and stx1/stx2, respectively. The stx1/stx2 and stx2 types were significantly higher during the grazing and finishing periods, respectively, in comparison with the rearing and grazing periods. The presence of stx2a subtype was evident in four isolates, whereas stx2c was present in at least seven. However, both subtypes were present simultaneously in two isolates. The stx1/stx2c, stx1/stx2d and stx1/stx2NT genotypes occurred in 24, 2 and 15 isolates, respectively. The simultaneous occurrence of stx1 and stx2c significantly increased during grazing. Some cases of within-pen and between-pen transmission occurred throughout the study. Contagion levels during in-field grazing were higher than during permanent confinement in the pens. Thus, the individual patterns of shedding varied depending on the proportion of animals shedding the bacteria within pens and the time of shedding.


Assuntos
Derrame de Bactérias , Doenças dos Bovinos/microbiologia , Infecções por Escherichia coli/veterinária , Escherichia coli O157/fisiologia , Adesinas Bacterianas/análise , Animais , Argentina , Bovinos , Infecções por Escherichia coli/microbiologia , Escherichia coli O157/genética , Escherichia coli O157/patogenicidade , Proteínas de Escherichia coli/análise , Fezes/microbiologia , Genótipo , Estudos Longitudinais , Masculino , Toxina Shiga/análise , Virulência
5.
Prev Vet Med ; 172: 104803, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31634754

RESUMO

The objective of this study was to investigate the new differential somatic cell count (DSCC) as a supplementary indicator to SCC for the identification of intramammary infection (IMI) in dairy cows at the end of the lactation period. Different approaches for identification of cows with IMI (i.e. often based on SCC) and targeted antimicrobial treatment of those rather than of all cows have been developed (i.e. selective dry cow treatment). Recently, DSCC representing the proportion of polymorphonuclear neutrophils and lymphocytes, has been introduced as an additional indicator for the presence of IMI. We used the last dairy herd improvement (DHI) samples taken within 42 d prior to dry-off as well as hand-stripped samples collected within 5 days prior to dry-off to measure DSCC and SCC. The bacteriological status was determined using quarter foremilk samples collected close to drying off. In total, 582 cows were dried off during our study but not all of them could be included in the data analysis for different reasons (e.g. incomplete data, samples too old for reliable determination of SCC and DSCC, contamination). Eventually, the final data set comprised of 310 cows of which 64 and 149 were infected with major and minor pathogens, respectively, and 97 were uninfected. The area under receiver-operating characteristics curves (AUC) were calculated to compare the diagnostic abilities of the different parameters. The AUC for identification of IMI by major pathogens when using the combination of DSCC and SCC was 0.64 compared to 0.62 for SCC alone and 0.62 for DSCC alone. The different parameters were further compared based on test characteristics and predictive values. For example, classifying cows as infected based on a cut-off of 200,000 cells/ml for SCC alone and in terms of using DSCC combined with SCC based on either >60% and/or >200,000 cells/ml, the sensitivity changed from 47 to 66% and the specificity from 74 to 54%. At the same time, the negative predictive value changed from 84 to 86% and the positive predictive value from 32 to 27%. Test characteristics and predictive values of the parameters DSCC and SCC were similar using DHI and hand-stripped samples. In conclusion, our study provides first indications on test characteristics and predictive values for the combination of DSCC and SCC. However, more work on this subject and the actual practical application is needed.


Assuntos
Doenças dos Bovinos/diagnóstico , Contagem de Células/veterinária , Glândulas Mamárias Animais/microbiologia , Mastite Bovina/diagnóstico , Animais , Bovinos , Doenças dos Bovinos/microbiologia , Contagem de Células/métodos , Feminino , Mastite Bovina/microbiologia , Sensibilidade e Especificidade
6.
BMC Vet Res ; 15(1): 371, 2019 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-31655595

RESUMO

BACKGROUND: Mycoplasma bovis is a causative agent of disease in cattle causing many clinical conditions. Currently there are no commercial M. bovis vaccines in Europe and treatment is difficult with decreased antimicrobial susceptibility of M. bovis field isolates. Using an M. bovis calf infection model the effectiveness of enrofloxacin given alone; in combination with flunixin meglumine, a nonsteroidal anti-inflammatory drug; and a group with an additional treatment of pegbovigrastim, an immunostimulator, was evaluated. RESULTS: Enrofloxacin given alone stimulated a strong immune response, reduced the clinical manifestation and lung lessions of the M. bovis infection. In contrast the combination therapy appeared ineffective. CONCLUSIONS: In this experiment enrofloxacin given alone appeared to be the most effective treatment of the M. bovis affected calves, whereas co-administration with flunixin meglumine, and pegbovigrastim was not beneficial in this trial.


Assuntos
Doenças dos Bovinos/tratamento farmacológico , Infecções por Mycoplasma/veterinária , Pneumonia/veterinária , Adjuvantes Imunológicos/uso terapêutico , Animais , Antibacterianos/uso terapêutico , Anti-Inflamatórios não Esteroides/uso terapêutico , Bovinos , Doenças dos Bovinos/microbiologia , Clonixina/análogos & derivados , Clonixina/uso terapêutico , Quimioterapia Combinada/veterinária , Enrofloxacina/uso terapêutico , Feminino , Fator Estimulador de Colônias de Granulócitos/uso terapêutico , Infecções por Mycoplasma/tratamento farmacológico , Mycoplasma bovis/efeitos dos fármacos , Pneumonia/tratamento farmacológico , Proteínas Recombinantes/uso terapêutico
7.
PLoS Pathog ; 15(10): e1008003, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31581229

RESUMO

Specific Escherichia coli isolates lysogenised with prophages that express Shiga toxin (Stx) can be a threat to human health, with cattle being an important natural reservoir. In many countries the most severe pathology is associated with enterohaemorrhagic E. coli (EHEC) serogroups that express Stx subtype 2a. In the United Kingdom, phage type (PT) 21/28 O157 strains have emerged as the predominant cause of life-threatening EHEC infections and this phage type commonly encodes both Stx2a and Stx2c toxin types. PT21/28 is also epidemiologically linked to super-shedding (>103 cfu/g of faeces) which is significant for inter-animal transmission and human infection as demonstrated using modelling studies. We demonstrate that Stx2a is the main toxin produced by stx2a+/stx2c+ PT21/28 strains induced with mitomycin C and this is associated with more rapid induction of gene expression from the Stx2a-encoding prophage compared to that from the Stx2c-encoding prophage. Bacterial supernatants containing either Stx2a and/or Stx2c were demonstrated to restrict growth of bovine gastrointestinal organoids with no restriction when toxin production was not induced or prevented by mutation. Isogenic strains that differed in their capacity to produce Stx2a were selected for experimental oral colonisation of calves to assess the significance of Stx2a for both super-shedding and transmission between animals. Restoration of Stx2a expression in a PT21/28 background significantly increased animal-to-animal transmission and the number of sentinel animals that became super-shedders. We propose that while both Stx2a and Stx2c can restrict regeneration of the epithelium, it is the relatively rapid and higher levels of Stx2a induction, compared to Stx2c, that have contributed to the successful emergence of Stx2a+ E. coli isolates in cattle in the last 40 years. We propose a model in which Stx2a enhances E. coli O157 colonisation of in-contact animals by restricting regeneration and turnover of the colonised gastrointestinal epithelium.


Assuntos
Doenças dos Bovinos/transmissão , Células Epiteliais/microbiologia , Infecções por Escherichia coli/veterinária , Escherichia coli O157/efeitos dos fármacos , Íleo/microbiologia , Organoides/microbiologia , Toxina Shiga II/farmacologia , Animais , Bovinos , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/microbiologia , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Infecções por Escherichia coli/tratamento farmacológico , Infecções por Escherichia coli/microbiologia , Escherichia coli O157/isolamento & purificação , Íleo/citologia , Íleo/metabolismo , Masculino , Organoides/crescimento & desenvolvimento , Organoides/metabolismo , Virulência
8.
Aust Vet J ; 97(12): 505-508, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31588995

RESUMO

Chlamydial infections in dairy cattle are common and have been sporadically associated with reduced performance and severe disease manifestations. While chlamydial infections are well described in sheep, very little is known about the epidemiology of these infections in dairy cattle in Australia. In this study, we screened for chlamydial infections and assessed on-farm risks in dairy cattle herds from Southeast Queensland (SE Qld) region of Australia. In total, 228 paired vaginal and rectal swabs were collected from 114 visually healthy dairy cows from four farms in SE Qld. Risk factors were rated by observational study and included: hygiene and cleanliness of cows, walkway and parlour, incidence of perinatal mortality, external replacements, mode of breeding, calving pen management, heat reduction strategies, and feed ration usage. Testing for chlamydial pathogens (Chlamydia pecorum, Chlamydia psittaci and Chlamydia abortus) was done using species-specific quantitative polymerase chain reaction (qPCR) assays. Detected rates of chlamydial infection were evaluated against the on-farm risk factors. C. pecorum infection was widespread in all four farms, with 56.1% (64/114) of individual animals shedding this organism from vaginal and rectal, or both sites. C. abortus and C. psittaci were not detected in any animals. No association was found to exist with risk factors and C. pecorum infection rates in our study, however the number of Chlamydia positive animals was statistically different between the herds. This study suggests that subclinical chlamydial infections may impact on dairy herd health at the production level rather than affecting individual animal.


Assuntos
Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/microbiologia , Infecções por Chlamydia/veterinária , Animais , Bovinos , Doenças dos Bovinos/diagnóstico , Chlamydia/isolamento & purificação , Infecções por Chlamydia/diagnóstico , Infecções por Chlamydia/epidemiologia , Indústria de Laticínios , Fazendas , Feminino , Queensland/epidemiologia , Reto/microbiologia , Fatores de Risco , Vagina/microbiologia
9.
Vet Clin North Am Food Anim Pract ; 35(3): 471-483, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31590898

RESUMO

Host responses are often ineffective at clearing Mycoplasma bovis infection and may contribute to the pathogenesis of disease. M bovis possesses a surprisingly large repertoire of strategies to evade and modulate host responses. Unopsonized M bovis impairs phagocytosis and killing by neutrophils and macrophages. Apoptosis of neutrophils and lymphocytes is enhanced, whereas it is delayed in macrophages. Both proinflammatory and antiinflammatory cytokines are stimulated during M bovis infection depending on the cell type and location, and overall systemic responses tend to have a T-helper 2 bias. M bovis reduces proliferation of T cells and, in chronic infection, causes T-cell exhaustion.


Assuntos
Doenças dos Bovinos/imunologia , Doenças dos Bovinos/microbiologia , Infecções por Mycoplasma/veterinária , Mycoplasma bovis/imunologia , Animais , Bovinos , Imunidade Celular , Imunidade Humoral , Infecções por Mycoplasma/imunologia
10.
J Dairy Sci ; 102(12): 11470-11475, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31629518

RESUMO

The objectives of this study were (a) to evaluate skin biopsies of udder sores and negative control cows for the presence of mange and nonbacterial pathogens via histopathology and (b) to identify and compare bacterial abundance in the lesions of cows with udder sores and from the skin of healthy controls from the same farms. Cows from 3 dairy farms with (n = 23) and without (n = 12) udder sore lesions were enrolled, and punch biopsies (23 lesions, 23 negative control samples of cows with lesions, and 12 control samples of cows without lesions) were collected. The biopsies were evaluated histopathologically, and their 16S metagenome was analyzed. No signs of mange or viral or fungal infections were detected histopathologically in any samples. The α diversity of microbial populations decreased in lesions, across all farms, and the abundance of spirochaetes did not notably change, compared with controls. However, compared with control samples, the microbial fractions of Fusobacterium, Helcococcus spp., Anaerococcus spp., Porphyromonas spp., Prevotella spp., and Trueperella spp. increased several-fold in lesions. In summary, our results suggest that spirochaetes, viruses, and mange are unlikely to cause udder sores. Instead, sores were associated with a marked increase in the abundance of Fusobacterium, Helcococcus, Anaerococcus, Porphyromonas, Prevotella, and Trueperella. Future studies are needed to determine which of these bacteria initiates this polymicrobial infection.


Assuntos
Doenças dos Bovinos/patologia , Glândulas Mamárias Animais/patologia , Mastite Bovina/patologia , Pele/patologia , Animais , Bactérias/classificação , Bactérias/genética , Biópsia/veterinária , Bovinos , Doenças dos Bovinos/microbiologia , Feminino , Glândulas Mamárias Animais/microbiologia , Mastite Bovina/microbiologia , Metagenoma , Pele/microbiologia
11.
Vet Ital ; 55(3): 247-252, 2019 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-31599549

RESUMO

Q fever is a widespread zoonotic disease caused by Coxiella burnetii, an obligate intracellular bacterium with a wide range of hosts. The aim of this study was to estimate the seroprevalence of C. burnetii infection in cattle in Sicilian farms. A total of 4,661 serum samples, from cattle belonging to 198 Sicilian farms, were examined by ELISA test and 246 resulted positive. The average seroprevalence at the farm level was 38.8% (77/198) (95% CI), while at the animal level it was 5.28% (246/4,661) (95% CI). The present study highlights the need for continuous monitoring of C. burnetii spread as it represents a serious risk for human health.


Assuntos
Doenças dos Bovinos/microbiologia , Coxiella burnetii/isolamento & purificação , Febre Q/veterinária , Animais , Bovinos , Doenças dos Bovinos/epidemiologia , Humanos , Febre Q/sangue , Febre Q/epidemiologia , Estudos Soroepidemiológicos , Sicília/epidemiologia , Zoonoses
12.
J Vet Diagn Invest ; 31(6): 893-898, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31646958

RESUMO

We investigated deaths in a group of feedlot steers in Argentina. The main findings in 3 steers autopsied were pulmonary congestion and edema, necrotizing myocarditis, pericarditis, suppurative leptomeningitis, and bronchopneumonia. Histophilus somni was detected by bacterial culture and immunohistochemistry in the hearts of the 3 animals. Partial sequences of the 16S rRNA gene of a H. somni isolate had 99% similarity with other H. somni sequences in GenBank. Most reports of H. somni septicemia in cattle originate from North America and western Europe. There is scant information about cardiac histophilosis in South America. A survey of diagnostic laboratory personnel in 7 South American countries documented various forms of bovine histophilosis in Argentina, Brazil, Uruguay, and Venezuela.


Assuntos
Doenças dos Bovinos/diagnóstico , Meningite/veterinária , Miocardite/veterinária , Infecções por Pasteurellaceae/veterinária , Pasteurellaceae/isolamento & purificação , Animais , Argentina , Brasil , Bovinos , Doenças dos Bovinos/microbiologia , Masculino , Meningite/diagnóstico , Meningite/microbiologia , Miocardite/diagnóstico , Miocardite/microbiologia , Pasteurellaceae/classificação , Infecções por Pasteurellaceae/diagnóstico , Infecções por Pasteurellaceae/microbiologia , RNA Bacteriano/análise , RNA Ribossômico 16S/análise , Uruguai , Venezuela
13.
BMC Vet Res ; 15(1): 368, 2019 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-31653234

RESUMO

BACKGROUND: The obligate intracellular bacterium Coxiella burnetii causes globally distributed zoonotic Q fever. Ruminant livestock are common reservoirs of C. burnetii. Coxiella burnetii are shed in large numbers in the waste of infected animals and are transmitted by inhalation of contaminated aerosols. This study was conducted to evaluate the prevalence of C. burnetii infection in domestic animals and ticks in areas of Slovenia associated with a history of Q fever outbreaks. RESULTS: A total of 701 ticks were collected and identified from vegetation, domestic animals and wild animals. C. burnetii DNA was detected in 17 out of 701 (2.4%) ticks. No C. burnetii DNA was found in male ticks. Ticks that tested positive in the PCR-based assay were most commonly sampled from wild deer (5.09%), followed by ticks collected from domestic animals (1.16%) and ticks collected by flagging vegetation (0.79%). Additionally, 150 animal blood samples were investigated for the presence of C. burnetii-specific antibodies and pathogen DNA. The presence of pathogen DNA was confirmed in 14 out of 150 (9.3%) blood samples, while specific antibodies were detected in sera from 60 out of 150 (40.4%) animals. CONCLUSIONS: Our results indicate that ticks, although not the primary source of the bacteria, are infected with C. burnetii and may represent a potential source of infection for humans and animals. Ticks collected from animals were most likely found to harbor C. burnetii DNA, and the infection was not lost during molting. The persistence and distribution of pathogens in cattle and sheep indicates that C. burnetii is constantly present in Slovenia.


Assuntos
Coxiella burnetii/isolamento & purificação , Febre Q/veterinária , Carrapatos/microbiologia , Animais , Anticorpos Antibacterianos/sangue , Bovinos , Doenças dos Bovinos/microbiologia , Coxiella burnetii/genética , Coxiella burnetii/imunologia , DNA Bacteriano/sangue , Cervos/microbiologia , Feminino , Masculino , Muda , Reação em Cadeia da Polimerase/veterinária , Prevalência , Febre Q/epidemiologia , Ovinos , Doenças dos Ovinos/microbiologia , Eslovênia/epidemiologia , Zoonoses
14.
J Dairy Sci ; 102(12): 11280-11290, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31563303

RESUMO

Feeding pasteurized milk to suckling calves is a popular practice used increasingly on dairy farms. Waste milk is frequently fed to calves because of its high nutritional value and economic benefits compared to milk replacement products. However, one of the disadvantages of feeding waste milk is the potential for exposure to a high number of bacterial contaminants, which may lead to serious illnesses or infections in calves. One of these contaminants is Mycobacterium avium ssp. paratuberculosis (MAP), the causative agent of Johne's disease (paratuberculosis). The transmission and distribution of paratuberculosis in dairy herds occurs mostly through the feeding newborn calves with contaminated colostrum or milk, because this age group is believed to be most susceptible to infection. To reduce the risk of transmission of pathogens, on-farm pasteurization of milk has become increasingly popular. In this study, we analyzed the efficacy of a new commercial high-temperature, short-time pasteurizer (73.5°C for 20 to 25 s) in terms of MAP inactivation under experimental on-farm conditions. The pasteurizer uses a newly developed steam-heating technique, allowing for the pasteurization of the transition milk without clumping. In 3 independent trials, we spiked fresh raw milk samples to a level of 107 or 104 viable MAP cells/mL before pasteurization. We examined the thermal inactivation and viability of MAP using culture and a D29 bacteriophage-based assay. To verify the identity and number of MAP cells, we also performed PCR assays. Pasteurization of the inoculated milk (107 and 104 MAP cells/mL) resulted in a remarkable reduction in viable MAP cells. The mean inactivation rate of MAP ranged from 0.82 to 2.65 log10 plaque-forming units/mL, depending on the initial MAP amount inoculated and the addition of conservative agents to the pasteurized milk. Nevertheless, approximately 103 MAP cells/mL remained viable and could be transferred to calves after high-temperature, short-time pasteurization of milk.


Assuntos
Ração Animal , Doenças dos Bovinos/prevenção & controle , Leite , Mycobacterium avium subsp. paratuberculosis , Paratuberculose/prevenção & controle , Pasteurização , Animais , Bovinos , Doenças dos Bovinos/microbiologia , Colostro/microbiologia , Indústria de Laticínios , Feminino , Temperatura Alta , Leite/microbiologia , Mycobacterium avium subsp. paratuberculosis/fisiologia , Pasteurização/métodos , Reação em Cadeia da Polimerase , Gravidez
15.
J Dairy Sci ; 102(12): 11260-11267, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31563316

RESUMO

Bovine paratuberculosis (Johne's disease) is a bacterial, chronic, and wasting intestinal disease caused by Mycobacterium avium ssp. paratuberculosis (MAP). Johne's disease causes severe losses in dairy farm productivity and is also suspected to be a potential trigger for Crohn's disease in humans. The fecal-oral infection of MAP to neonates is recognized as an important within-herd transmission route. Our objective was to recommend diagnostic methods for herds with suspected paratuberculosis requiring fast results, as well as for herds with breeding programs or others that aim at being nonsuspected of paratuberculosis infection. We determined a period of 8 wk from sampling to diagnostic findings suitable for testing of cows during the dry period. We therefore tested environmental and individual fecal samples with one rapid and one highly sensitive diagnostic method. Environmental samples (boot swabs) were taken as a first step in 3 herds and tested using a DNA extraction protocol for feces and subsequent real-time PCR (referred to as fecal PCR). Additionally, cultivation in liquid medium for 6 wk was performed and verified with real-time PCR (referred to as liquid culture). Automation of DNA extraction based on magnetic beads and the PCR setup was performed with pipetting robots. As a result, we successfully detected MAP in boot swabs of all herds by both methods. In a second step, 245 individual fecal samples from the 3 herds were examined using also fecal PCR and liquid culture. The results obtained by fecal PCR were compared with detection of MAP using cultivation in liquid medium for 6 wk. Testing individual cows, we identified MAP-specific DNA in 53 fecal samples using the liquid culture. Using fecal PCR, we revealed 43 positive samples of which 39 also tested positive in the liquid culture, revealing MAP-positive cows in all 3 herds. The fecal PCR procedure allows rapid detection of MAP-specific DNA with 74% of the sensitivity of liquid culture. For the purpose of testing with maximal sensitivity, cultivation in liquid medium is recommended. Cultivation of MAP in liquid medium M7H9C means a significant time gain in comparison to cultivation on solid media, which requires twice as much time. Thus, this testing fits within the 6- to 8-wk dry period of gravid cows and provides test results before calving, a prerequisite to prevent fecal-oral transmission to newborn calves.


Assuntos
Doenças dos Bovinos/diagnóstico , Fezes/microbiologia , Mycobacterium avium subsp. paratuberculosis , Paratuberculose/diagnóstico , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Animais , Cruzamento , Bovinos , Doenças dos Bovinos/microbiologia , Microbiologia Ambiental , Feminino , Mycobacterium avium subsp. paratuberculosis/genética , Paratuberculose/microbiologia
16.
J Anim Sci ; 97(11): 4567-4578, 2019 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-31563955

RESUMO

Liver abscesses in feedlot cattle are detrimental to animal performance and economic return. Tylosin, a macrolide antibiotic, is used to reduce prevalence of liver abscesses, though there is variable efficacy among different groups of cattle. There is an increased importance in better understanding the etiology and pathogenesis of this condition because of growing concern over antibiotic resistance and increased scrutiny regarding use of antibiotics in food animal production. The objective of this study was to compare the microbiomes and antimicrobial resistance genes (resistomes) of feces of feedlot cattle administered or not administered tylosin and in their pen soil in 3 geographical regions with differing liver abscess prevalences. Cattle (total of 2,256) from 3 geographical regions were selected for inclusion based on dietary supplementation with tylosin (yes/no). Feces and pen soil samples were collected before harvest, and liver abscesses were identified at harvest. Shotgun and 16S rRNA amplicon sequencing were used to evaluate the soil and feces. Microbiome and resistome composition of feces (as compared by UniFrac distances and Euclidian distances, respectively) did not differ (P > 0.05) among tylosin or no tylosin-administered cattle. However, feedlot location was associated with differences (P ≤ 0.05) of resistomes and microbiomes. Using LASSO, a statistical model identified both fecal and soil microbial communities as predictive of liver abscess prevalence in pens. This model explained 75% of the variation in liver abscess prevalence, though a larger sample size would be needed to increase robustness of the model. These data suggest that tylosin exposure does not have a large impact on cattle resistomes or microbiomes, but instead, location of cattle production may be a stronger driver of both the resistome and microbiome composition of feces.


Assuntos
Antibacterianos/administração & dosagem , Doenças dos Bovinos/prevenção & controle , Suplementos Nutricionais/análise , Abscesso Hepático/veterinária , Microbiota/efeitos dos fármacos , Tilosina/administração & dosagem , Ração Animal/análise , Animais , Bovinos , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/microbiologia , Farmacorresistência Bacteriana , Fezes/microbiologia , Feminino , Geografia , Abscesso Hepático/epidemiologia , Abscesso Hepático/microbiologia , Abscesso Hepático/prevenção & controle , Masculino , Metagenômica , Microbiota/genética , Modelos Estatísticos , Prevalência , Microbiologia do Solo
17.
Lett Appl Microbiol ; 69(5): 366-372, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31508837

RESUMO

We evaluate the efficacy of recombinant DNA vaccine ABA392 against haemorrhagic septicaemia infection through intranasal administration route by targeting the mucosal immunity. The DNA vaccine was constructed and subjected to animal study using the Sprague Dawley (SD) rat. The study was divided into two major parts: (i) active and (ii) passive immunization studies, involving 30 animals for each part. Each group was then divided into five test groups: two test samples G1 and G2 with 50 and 100 µg ml-1 purified DNA vaccine; one positive control G5 with 106  CFU per ml formalin-killed PMB2; and two negative controls, G3 and G4 with normal saline and pVAX1 vector. Both studies were conducted for the determination of immunogenicity by total white blood cell count (TWBC), indirect ELISA and histopathological changes for the presence of the bronchus-associated lymphoid tissue (BALT). Our findings demonstrate that TWBC, IgA and IgG increased after each of the three vaccination regimes: groups G1, G2 and G5. Test samples G1 and G2 showed significant differences (P < 0·05) compared to the negative controls, G3 and G4, but no significant differences from the positive control G5. Groups G1, G2 and G5 showed more formation of BALT compared to the negative controls, G3 and G4. Our results show that intranasal inoculation of recombinant DNA vaccine ABA392 can provoke mucosal immunity which makes it a potential prophylactic against HS. SIGNIFICANCE AND IMPACT OF THE STUDY: New approach of combating haemorrhagic septicaemia disease among bovines by recombinant DNA vaccine is crucial to overcome the loss of edible products from the infected bovines. DNA vaccine can potentially serve as a better immunogen which would elicit both cellular and humoral immunity, and it is also stable for its molecular reproduction. This research report demonstrates an effective yet simple way of administering the DNA vaccine via the intranasal route in rats, to provoke the mucosal immunity through the development of immunoglobulins IgA, IgG and bronchus-associated lymphoid tissue which guard as the first-line defence at the host's mucosal lining.


Assuntos
Vacinas Bacterianas/administração & dosagem , Doenças dos Bovinos/prevenção & controle , Septicemia Hemorrágica/veterinária , Pasteurella multocida/imunologia , Vacinas de DNA/administração & dosagem , Administração Intranasal , Animais , Anticorpos Antibacterianos/imunologia , Vacinas Bacterianas/genética , Vacinas Bacterianas/imunologia , Bovinos , Doenças dos Bovinos/imunologia , Doenças dos Bovinos/microbiologia , DNA Recombinante/administração & dosagem , DNA Recombinante/genética , DNA Recombinante/imunologia , Ensaio de Imunoadsorção Enzimática , Septicemia Hemorrágica/imunologia , Septicemia Hemorrágica/microbiologia , Septicemia Hemorrágica/prevenção & controle , Imunização Passiva , Masculino , Pasteurella multocida/genética , Ratos , Ratos Sprague-Dawley , Vacinas de DNA/genética , Vacinas de DNA/imunologia
18.
J Vet Diagn Invest ; 31(6): 899-904, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31510908

RESUMO

A prior multilocus sequence typing (MLST) study reported that Mycoplasma bovis isolates from North American bison possess sequence types (STs) different from those found among cattle. The 42 bison isolates evaluated were obtained in 2007 or later, whereas only 19 of 94 (~20%) of the available cattle isolates, with only 1 from North America, were from that same time. We compared STs of additional, contemporary, North American cattle isolates with those from bison, as well as isolates from 2 North American deer, all originating during the same timeframe, to more definitively assess potential strain-related host specificity and expand our understanding of the genetic diversity of M. bovis. From 307 isolates obtained between 2007 and 2017 (209 from cattle, 96 from bison, 2 from deer), we identified 49 STs, with 39 found exclusively in cattle and 5 exclusively in bison. Four STs were shared between bison and cattle isolates; one ST was found in cattle and in a deer. There was no clear association between ST and the health status of the animal of origin. An MLST-based phylogeny including 41 novel STs identified in our study reveals that STs found in bison fall within several divergent lineages that include STs found exclusively in cattle.


Assuntos
Bison , Doenças dos Bovinos/diagnóstico , Cervos , Infecções por Mycoplasma/veterinária , Mycoplasma bovis/classificação , Animais , Canadá , Bovinos , Doenças dos Bovinos/classificação , Doenças dos Bovinos/microbiologia , Tipagem de Sequências Multilocus/veterinária , Infecções por Mycoplasma/classificação , Infecções por Mycoplasma/diagnóstico , Infecções por Mycoplasma/microbiologia , Mycoplasma bovis/genética , Estados Unidos
19.
Parasit Vectors ; 12(1): 448, 2019 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-31511038

RESUMO

BACKGROUND: Public interest for tick-borne pathogens in cattle livestock is rising due to their veterinary and zoonotic importance. Consequently, correct identification of these potential pathogens is crucial to estimate the level of exposition, the risk and the detrimental impact on livestock and the human population. RESULTS: Conventional PCR with generic primers was used to identify groups of tick-borne pathogens in cattle breeds from northern Cameroon. The overall prevalence in 1260 blood samples was 89.1%, with 993 (78.8%) positive for Theileria/Babesia spp., 959 (76.1%) for Anaplasma/Ehrlichia spp., 225 (17.9%) for Borrelia spp., and 180 (14.3%) for Rickettsia spp. Sanger sequencing of a subset of positively-tested samples revealed the presence of Theileria mutans (92.2%, 130/141), T. velifera (16.3%, 23/141), Anaplasma centrale (10.9%, 15/137), A. marginale (30.7%, 42/137), A. platys (51.1%, 70/137), Anaplasma sp. 'Hadesa' (10.9%, 15/137), Ehrlichia ruminantium (0.7%, 1/137), E. canis (0.7%, 1/137), Borrelia theileri (91.3%, 42/46), Rickettsia africae (59.4%, 19/32) and R. felis (12.5%, 4/32). A high level of both intra- and inter-generic co-infections (76.0%) was observed. To the best of our knowledge, B. theileri, T. mutans, T. velifera, A. platys, Anaplasma sp. 'Hadesa', R. felis and E. canis are reported for the first time in cattle from Cameroon, and for R. felis it is the first discovery in the cattle host. Babesia spp. were not detected by sequencing. The highest number of still identifiable species co-infections was up to four pathogens per genus group. Multifactorial analyses revealed a significant association of infection with Borrelia theileri and anemia. Whereas animals of older age had a higher risk of infection, the Gudali cattle had a lower risk compared to the other local breeds. CONCLUSION: Co-infections of tick-borne pathogens with an overall high prevalence were found in all five study sites, and were more likely to occur than single infections. Fulani, Namchi and Kapsiki were the most infected breed in general; however, with regions as significant risk factor. A better-adapted approach for tick-borne pathogen identification in co-infected samples is a requirement for epidemiological investigations and tailored control measures.


Assuntos
Babesia/isolamento & purificação , Bactérias/isolamento & purificação , Doenças dos Bovinos/epidemiologia , Theileria/isolamento & purificação , Doenças Transmitidas por Carrapatos/veterinária , Animais , Babesia/classificação , Bactérias/classificação , Infecções Bacterianas/epidemiologia , Infecções Bacterianas/microbiologia , Infecções Bacterianas/veterinária , Camarões/epidemiologia , Bovinos , Doenças dos Bovinos/microbiologia , Doenças dos Bovinos/parasitologia , Coinfecção/epidemiologia , Coinfecção/microbiologia , Coinfecção/parasitologia , Coinfecção/veterinária , Reação em Cadeia da Polimerase , Prevalência , Infecções Protozoárias em Animais/epidemiologia , Infecções Protozoárias em Animais/parasitologia , Theileria/classificação , Doenças Transmitidas por Carrapatos/epidemiologia , Doenças Transmitidas por Carrapatos/microbiologia , Doenças Transmitidas por Carrapatos/parasitologia
20.
Braz J Microbiol ; 50(4): 1105-1114, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31541428

RESUMO

The Mycobacterium avium subspecies paratuberculosis (MAP) causes paratuberculosis (Johne's disease), a systemic and chronic inflammation of intestine that affects bovine, small ruminants like goat and sheep. The disease has a greater economic importance in cattle and in small ruminants. But its effective control is impeded due to lack of rapid and accurate diagnostics. The present study is aimed at developing a LAMP-coupled lateral flow device (LFD) for rapid detection of paratuberculosis in livestock animal species such as cattle and in small ruminants at resource-limited areas. LAMP primers with biotin and FITC end tags were designed for IS900 gene specific for MAP. To determine sensitivity of LAMP assay, 10-fold serial dilutions were made from 10 ng/µl MAP stock DNA and were compared with PCR. The detection limits of LAMP-coupled LFD were defined and reactions were repeated for reproducibility. The specificity was evaluated using other infectious bacteria such as M. bovis, M. tuberculosis, Brucella abortus, Leptospira interrogan, Yersinia enterocolitica, Salmonella typhimurium, Listeria monocytogens, and Staphylococcus aureus. A total of 95 samples turned positive for LAMP-coupled LFD out of 389 fecal samples. All the cultural-positive and PCR-positive samples showed positive in LAMP-coupled LFD. Nine samples with negative cultures turned positive in LAMP assay. The overall sensitivity and specificity of the LAMP-coupled LFD assays were 100% and 97.02% respectively in comparison with the culture as the gold standard method. The sensitivity detection limit of developed assay was 10 fg/µl and specificity was 100%. This assay successfully detected MAP not only by using bacterial DNA but also in clinical fecal samples. The clear band formation at control and test positions was observed on LAMP-coupled LFD. The developed assay is a simple, rapid, easy to perform, and is very useful in early diagnosis of Mycobacterium avium subsp. paratuberculosis at point of care resource-limited areas.


Assuntos
Mycobacterium avium subsp. paratuberculosis/isolamento & purificação , Técnicas de Amplificação de Ácido Nucleico/métodos , Paratuberculose/microbiologia , Animais , Bovinos , Doenças dos Bovinos/diagnóstico , Doenças dos Bovinos/microbiologia , Primers do DNA/genética , Doenças das Cabras/diagnóstico , Doenças das Cabras/microbiologia , Cabras , Mycobacterium avium subsp. paratuberculosis/classificação , Mycobacterium avium subsp. paratuberculosis/genética , Técnicas de Amplificação de Ácido Nucleico/instrumentação , Paratuberculose/diagnóstico , Sistemas Automatizados de Assistência Junto ao Leito , Sensibilidade e Especificidade , Ovinos , Doenças dos Ovinos/diagnóstico , Doenças dos Ovinos/microbiologia
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