RESUMO
This study aimed to investigate seven outbreaks of A. marginale infection in two regions of Brazil, affecting taurine, zebu, and crossbred cattle. We assessed the possible causes, treatment measures, and genetic diversity of A. marginale. These outbreaks occurred in two states (Goiás: outbreaks 1-7; Mato Grosso do Sul: outbreak 3), breeds (Holstein, Nellore, and crossbreed), age groups (beef cattle: 18-25 days old and 7-8 months; dairy cattle: 18-25 days old, 13-14 months, and cow after the first birth) and rearing systems (feedlot, pasture, pen in a wood shaving bedding system and compost bedded-pack barns). Metaphylactic or prophylactic treatments varied according to outbreak (imidocarb dipropionate: outbreaks 1-4 and 6; enrofloxacin: outbreaks 5 and 7; diminazene diaceturate: outbreak 5). In outbreaks 6 and 7, the packed cell volume was monitored. In all outbreaks, the practice of needle/syringe sharing was discontinued. For outbreaks 1-3, clinical signs and mortality (range, 4.8-13.3%) occurred 36-45 days after entry into the feedlot. In outbreak 4, A. marginale was diagnosed in 66.2% of the calves (bacteremia, 0-4.5%), with a mortality of 8.6%. Among nursing calves aged 60 days during outbreak 5, 53.8% were infected with A. marginale, with average bacteremia of 2.7% (range, 0-21.3%), and a mortality of 13.8%. In dairy heifers aged 14 months, raised in paddocks lacking vegetation cover and infested with R. microplus, then transitioned to a rotational grazing system also infested with R. microplus, the A. marginale bacteremia ranged from 3.2 to 6.7%, with a mortality of 20%. Before monitoring during outbreak 7, the mortality was 17.9%, but no further deaths were observed after monitoring initiation. In conclusion, possible causes triggering the outbreaks included primary tick infestation, needle/syringe sharing, and stress factors which may have affected the immunological statues of animals in the feedlots. Control measures performed in all outbreaks were effective. The partial msp4 gene sequences of A. marginale generated herein belonged to two haplotypes, but further research would be needed to investigate if this finding has any clinical significance.
Assuntos
Anaplasma marginale , Anaplasmose , Doenças dos Bovinos , Surtos de Doenças , Variação Genética , Animais , Brasil/epidemiologia , Bovinos , Surtos de Doenças/veterinária , Anaplasmose/epidemiologia , Anaplasmose/microbiologia , Anaplasma marginale/genética , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/microbiologia , Feminino , Criação de Animais Domésticos/métodos , MasculinoRESUMO
Anaplasmosis and babesiosis are globally distributed arthropod-borne diseases known for causing substantial economic losses due to their high morbidity and mortality rates. This study aims to assess the frequency and epidemiological features associated with the infection of Anaplasma marginale, Babesia bigemina, and Babesia bovis in three Creole cattle breeds (Chino Santandereano (Chino), Casanareño (CAS), and Sanmartinero (SM)) in northeastern Colombia. Between June 2019 and March 2020, a total of 252 Creole cattle were sampled, with Chino, CAS, and SM accounting for 42.8%, 29.5%, and 29.5% of the samples, respectively. Blood samples were subjected to molecular analysis to detect the DNA of A. marginale, B. bigemina, and B. bovis, using species-specific primers. Additionally, Packed Cell Volume (PCV), total serum proteins, and body condition were evaluated. Molecular analyses revealed the presence of B. bigemina, A. marginale, and B. bovis in 83.7% (211/252; 95% CI = 79.1%-88.3%), 59.9% (151/252; 95% CI = 53.8%-66.1%), and 40.9% (103/252; 95% CI = 34.7%-46.9%) of the samples, respectively, with 69% (174/252; 95% CI = 57.8%-80.3%) exhibiting coinfections. Notably, in infected animals, no significant alterations in PCV, total serum proteins, or body condition were observed. Multivariate analyses indicated a statistically significant association between the frequency of A. marginale infection and the breed and season, with a higher frequency in SM during the rainy season (P < 0.05). To our knowledge, this is the first molecular survey that evaluates multiple arthropod-borne pathogens in Colombian Creole breeds. The results revel a high frequency of B. bigemina and A. marginale infections, coupled with a notable frequency of coinfections, all without significant alteration in the PCV, total serum proteins and body conditions. Our findings enhance the understanding of the epidemiological aspects of arthropod-borne pathogens in Colombian Creole breed and contribute to the improvement of sanitary programs for these animals.
Assuntos
Anaplasma marginale , Anaplasmose , Babesia bovis , Babesia , Babesiose , Doenças dos Bovinos , Animais , Bovinos , Colômbia/epidemiologia , Babesiose/epidemiologia , Babesiose/parasitologia , Anaplasma marginale/genética , Anaplasma marginale/isolamento & purificação , Anaplasmose/epidemiologia , Anaplasmose/microbiologia , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/parasitologia , Doenças dos Bovinos/microbiologia , Babesia/isolamento & purificação , Babesia/genética , Babesia/classificação , Babesia bovis/genética , Babesia bovis/isolamento & purificação , Feminino , Masculino , PrevalênciaRESUMO
Bovine anaplasmosis presents a significant challenge to livestock production in tropical, subtropical, and temperate regions. For many years, the concept of enzootic stability/instability (initially established for babesiosis) and herd seroprevalence as an indicator of outbreak risks have been applied to anaplasmosis. However, this model has never been definitively validated for Anaplasma marginale. The objective of this study was to examine the relationship between herd immunity (seroprevalence) and the occurrence of anaplasmosis outbreaks in Southern Brazil. A case-control study was conducted, categorizing farms into two groups: cases (farms with a history of clinical anaplasmosis) and controls (those without anaplasmosis). Thirteen farms were identified as "cases", while 23 were identified as "controls". A substantial difference in seroprevalence distribution between the two groups was observed. The majority of "control" farms exhibited over 75% of animals with antibodies to A. marginale in both calves and heifers, whereas the majority of "case" farms had a seropositive cattle percentage below 75%. Additionally, twelve months after cattle serology tests, we conducted a prospective follow-up survey to identify any clinical cases of anaplasmosis. Statistical associations (P < 0.05) were found between both retrospective and prospective anaplasmosis outbreaks and the hypothetical threshold of herd seroprevalence (75%). We hypothesize that herd seroprevalence may be an indicator of the risk of occurrence of clinical anaplasmosis. It appears that the epidemiology of cattle anaplasmosis, at least in our conditions, aligns with the well-known model of enzootic stability/instability originally applied to bovine babesiosis.
Assuntos
Anaplasma marginale , Anaplasmose , Babesiose , Doenças dos Bovinos , Animais , Bovinos , Feminino , Anaplasmose/epidemiologia , Babesiose/epidemiologia , Brasil/epidemiologia , Estudos Soroepidemiológicos , Estudos de Casos e Controles , Estudos Retrospectivos , Estudos Prospectivos , Doenças dos Bovinos/epidemiologiaRESUMO
Anaplasmosis is a widely distributed vector-borne disease of cattle caused by the bacteria Anaplasma marginale, which may lead to severe losses in beef and dairy cattle production. Anecdotal information among farmers suggested that some cows may deliver calves more resilient to anaplasmosis. To investigate this, we tested two hypotheses: (i) whether the parity order or (ii) cow antibody levels may influence the humoral immunity of pre-weaning calves against cattle anaplasmosis. For this study, we sampled 170 cattle (Bos taurus taurus, Angus breed) on a farm in Southern Brazil, comprising 85 cows (50 multiparous and 35 primiparous) and their 85 calves (50 days old). Antibodies against A. marginale were investigated using iELISA. Eighty percent of the animals were considered seropositive (100% of the cows and 60% of the calves). There was no significant difference in seroprevalence between calves from primiparous and multiparous cows. However, calves from multiparous cows exhibited higher antibody levels. To address the second question, we classified cows based on their antibody levels to A. marginale (high or low). Calves from cows with high antibody levels also showed elevated antibody levels against A. marginale. Furthermore, calves from cows with high antibody levels had approximately four times greater odds of being seropositive for A. marginale at 50 days old than those born to mothers with low antibody levels. In conclusion, the calf's antibody level against A. marginale appears to be related to the cow's parity order and the mother's antibody level.
Assuntos
Anaplasma marginale , Anaplasmose , Doenças dos Bovinos , Gravidez , Feminino , Bovinos , Animais , Anaplasmose/epidemiologia , Imunidade Humoral , Estudos Soroepidemiológicos , Paridade , Doenças dos Bovinos/epidemiologiaRESUMO
Anaplasmosis, caused by bacteria of the genus Anaplasma, is an important tick-borne disease that causes economic losses to livestock farms in many countries. Even though Anaplasma spp. have been detected in goats and sheep worldwide, few studies investigate the occurrence and genetic identity of these agents in small ruminants from Brazil. Thus, this work aimed to detect and determine the genetic identity of Anaplasma spp. in small ruminants from the Baixo Parnaíba region, state of Maranhão, northeastern Brazil. For this purpose, blood samples were collected from 161 animals (91 goats; 70 sheep) from 4 municipalities in the Baixo Parnaíba region. Sheep and goat serum samples were subjected to recombinant membrane surface protein (MSP5)-based iELISA. Whole blood samples were subject to DNA extraction and molecular diagnosis using PCR assays for Anaplasma spp. targeting msp1ß, msp1α, 16S rRNA and msp4 genes. Positive samples were sequenced and then subjected to Anaplasma marginale msp1α genetic diversity analysis and phylogenetic inferences based on the 16S rRNA and msp4 genes. The serological survey detected the presence of anti-A. marginale IgG antibodies in 18 animals (11.1%): 2.9% (2/70) sheep and 17.4% (16/91) goats. Anaplasma marginale DNA was detected in 2 goats (1.2%) using qPCR based on the msp1ß gene. Two distinct A. marginale msp1α strains, namely α ß and α ß ΓγΓγΓγΓγ were found in the infected goats, each one found in a different animal, both belonging to the H genotype. Phylogenetic analysis based on the 16S rRNA gene showed the sequences positioned in three different clades and grouped with sequences from 'Candidatus Anaplasma boleense', A. platys and A. marginale. Phylogenetic inferences based on the msp4 gene positioned the sequence variants in the A. marginale clade. The present work represents the first molecular detection of sequence variants phylogenetic associated to 'Candidatus Anaplasma boleense' and A. platys and α ß and α ß ΓγΓγΓγΓγ in goats from Brazil.
Assuntos
Anaplasma marginale , Anaplasmose , Doenças das Cabras , Doenças dos Ovinos , Animais , Ovinos , Anaplasma/genética , RNA Ribossômico 16S/genética , Brasil/epidemiologia , Filogenia , Anaplasmose/microbiologia , Ruminantes , Anaplasma marginale/genética , Proteínas de Membrana/genética , Cabras/microbiologia , DNA , Doenças das Cabras/epidemiologia , Doenças dos Ovinos/epidemiologia , Doenças dos Ovinos/microbiologiaRESUMO
The aim of this study was to investigate the association between chronic Anaplasma marginale and Babesia spp. infection and hematological parameters of pregnant and non-pregnant taurine heifers. Blood samples from 94 females were collected on the first day (D-10) of timed artificial insemination (TAI) protocol and on pregnancy diagnosis (D+34). Hematological parameters were determined and compared between pregnant (PG) and non-pregnant (NPG) heifers, and within group at different sampling days. Real-time PCR (qPCR) was used to determine A. marginale and Babesia bovis infection, and for absolute quantification of Babesia spp. between PG and NPG groups. Correlation analysis was performed between the number of gDNA copies (CN) of Babesia spp. and hematological parameters. On D-10, mean hemoglobin concentration was higher for NPG, and hematocrit and total plasma protein were higher on D+34 for both groups. There was no difference in Babesia spp. CN between groups. In the first qPCR, all heifers were positive for A. marginale and B. bovis. Significant correlations were found between hemoglobin and erythrocyte and between hemoglobin and hematocrit (r = 0.8082 and r = 0.3009, respectively). Low levels of A. marginale and Babesia spp. did not affect hematological parameters of chronically infected pregnant and non-pregnant taurine heifers.
Assuntos
Anaplasma marginale , Babesia bovis , Babesia , Babesiose , Doenças dos Bovinos , Gravidez , Animais , Bovinos , Feminino , Babesiose/diagnóstico , Taurina , Doenças dos Bovinos/diagnósticoRESUMO
The study was conducted with the objective of estimating genetic and phenotypic parameters for tick (CRM) and Babesia bigemina (IBBi), Babesia bovis (IBBo), and Anaplasma marginale (IAM) burden in Angus female breed in Brazil. The sample group was composed of Angus females raised in herds located in a region of endemic instability for cattle tick fever in the state of Rio Grande Sul (RS), Brazil. The variance components were estimated using Bayesian inference and Gibbs sampling algorithm, considering a multi-trait animal model. Heritability estimates showed values of low magnitude, ranging from 0.03 (IBBo) to 0.16 (CRM), while repeatability estimates ranged between 0.07 (IBBo) and 0.21 (CRM). Regarding the genetic correlation estimates, the values showed low (-0.01 for IBBo × IAM) to moderate (0.55 between IBBi × IAM) magnitudes. The results indicate that it is possible to use tick count and hemoparasite infection levels as selection criteria, with small genetic gains.
Assuntos
Anaplasma marginale , Babesia , Babesiose , Feminino , Animais , Teorema de Bayes , Algoritmos , Babesia/genética , Babesiose/epidemiologiaRESUMO
The present work reviews the epidemiologic situation of Anaplasma marginale and Babesia spp. infections and the occurrence of cattle tick fever outbreaks in Brazil. In areas of tick fever enzootic instability, environmental conditions interfere with the development of Rhipicephalus (Boophilus) microplus: chilly winter in the southern region, floods in the Pantanal, and low humidity in the Caatinga. In contrast, the climatic conditions of stable zones (Cerrado, Amazon and Atlantic Forest biomes) favor tick development. In enzootic areas, tick fever is uncommon because the animals are in frequent contact with the parasite, acquiring immunity naturally during the period of innate resistance; however, outbreaks may occur when calves become infested by considerable numbers of infected ticks during this period or in adults raised in tick-free environments that become infested for the first time when transporting to stable areas. It is necessary to better understand the disease's risk factors under stable conditions and the implications of the mechanical and other vector transmission of A. marginale. To prevent tick fever outbreaks in Brazil, it is important to develop and use anaplasmosis and babesiosis vaccines in cattle from enzootic unstable regions, especially when animals are moved to stable areas.
Assuntos
Anaplasma marginale , Anaplasmose , Babesiose , Doenças dos Bovinos , Rhipicephalus , Animais , Bovinos , Brasil/epidemiologia , Babesiose/epidemiologia , Anaplasmose/epidemiologia , Doenças dos Bovinos/epidemiologiaRESUMO
Immunization of calves with Anaplasma centrale is used to prevent acute anaplasmosis caused by A. marginale. Natural and vaccine-acquired immunity is detected through serologic tests based primarily on A. marginale recombinant major surface protein 5 (MSP5m) because it has 91% identity with MSP5 from A. centrale (MSP5c). We developed a displacement, double-antigen, sandwich ELISA (ddasELISA) to detect antibodies against A. marginale or A. centrale. For ddasELISA validation, we analyzed serum samples positive for antibodies against Anaplasma spp. from cattle naturally infected with A. marginale (n = 300) or vaccinated with A. centrale (n = 255). Species-specific nested PCR (nPCR) assays were used to confirm infection. The optical density (OD) values obtained from antibodies directed at unique epitopes of A. marginale (ODAm) or A. centrale (ODAc) were used in the formula ODAm/ODAc. If the derived ratio was >0.38, the serum sample was considered positive for antibodies against A. marginale, with 98.9% sensitivity and 98.0% specificity. In a field evaluation, we analyzed 702 Anaplasma spp. antibody-positive serum samples from 34 herds by ddasELISA and nPCR; 571 were classified by ddasELISA as A. marginale-infected or A. centrale-vaccinated, with 84% agreement (κ = 0.70) between ddasELISA and nPCR. Our results indicate that ddasELISA could be used as a cost-effective alternative to molecular techniques to confirm infection with A. marginale in countries in which prevention is based on vaccination with A. centrale.
Assuntos
Anaplasma centrale , Anaplasma marginale , Anaplasmose , Doenças dos Bovinos , Bovinos , Animais , Anaplasmose/diagnóstico , Anaplasmose/prevenção & controle , Anaplasma , Ensaio de Imunoadsorção Enzimática/veterinária , Ensaio de Imunoadsorção Enzimática/métodos , Proteínas Recombinantes , Doenças dos Bovinos/diagnóstico , Doenças dos Bovinos/prevenção & controleRESUMO
Infections by Anaplasma marginale and infestations by Rhipicephalus microplus occur endemically in Brazil, representing an obstacle to expanding the use of taurine breeds, which are more susceptible. In this study, the levels of infection by A. marginale and infestation by R. microplus were monitored in 31 calves that were either purebred or had a high degree of taurine blood: 17 Angus (100% taurine) and 14 Ultrablack (ca. 82% taurine and 18% Zebu). The animals were evaluated on 13 occasions at 12-day intervals. The levels of A. marginale infection were determined by quantification of DNA copy number (CN) by qPCR, and ticks were monitored by two methods: counting adult females (≥ 4.5 mm) and scoring the level of tick infestation considering all visible instars in the animals' bodies. No significant effects were observed between the means of CN of A. marginale, tick counts and scores among Angus and Ultrablack animals. The repeatability estimates for CN of A. marginale, tick counts and tick scores were 0.53, 0.12 and 0.16, respectively. The correlations between CN and tick counts and scores were close to zero, whereas the correlations between tick assessment methods were 0.57. The absence of differences between the two genetic groups indicates, under the conditions of the present study, that the low degree of Zebu blood did not influence the levels of infection by A. marginale or infestation by R. microplus. The results also suggest that the evaluation of the levels of infestation by ticks using scores can provide information closer to the real infestation rate considering that it uses all the visible instars of the parasites.