Molecular and serological detection of Babesia bovis- and Babesia bigemina-infection in bovines and water buffaloes raised jointly in an endemic field

Detection and quantification of Babesia bovis and Babesia bigemina using different target genes

Molecular assays have been widely used for the detection and quantification of bovine babesiosis due to their high sensitivity and specificity. However, variations in the sensitivity of pathogen detection may occur depending on the selected target gene. Thus, this study aimed to compare the detection sensitivity (DS) of Babesia bovis and B. bigemina infection levels in artificially and naturally infected cattle using quantitative PCR (qPCR) and six target genes. For B. bovis, the merozoite surface antigen genes 2b and 2c (msa-2b and msa-2c), and the mitochondrial cytochrome b gene (cybmt) were used. For B. bigemina, the genes encoding the proteins associated with rhoptry 1c (rap-1c), rap-1a, and cybmt were used. Six bovines, free of babesiosis, were artificially infected with 1 × 10-8 red blood cells infected (iRBC) with B. bovis (n = 3) or 1 × 10-6B. bigemina iRBC (n = 3). The animals were evaluated daily until parasitemia was confirmed (≥ 2.0%). The quantity of iRBC present in each animal was determined by examining blood smears. Blood samples were then subjected to DNA extraction, serial dilution, and qPCR analysis to determine the DS of each target gene. In addition, 30 calves naturally infected by Babesia spp. were also evaluated using the same six target genes. Regarding the artificial infection, B. bovis cybmt showed 25-fold higher sensitivity than the msa-2b and msa-2c genes, while the B. bigemina cybmt exhibited 5-fold and 25-fold higher sensitivity than the rap-1a and rap-1c genes, respectively. The rap-1a gene was found to be 5 times more sensitive than the rap-1c gene, while the B. bovis msa-2b and msa-2c genes exhibited similar DS. The positive frequencies of naturally infected calves for the target cybmt, msa-2b, and msa-2c genes (B. bovis) were: 100%, 33.3% and 50%, while cybmt, rap-1a, and rap-1c genes (B. bigemina) were 90%, 83.3%, and 63.3%, respectively. This study may contribute to the selection of suitable genes for molecular monitoring of bovine babesiosis. Mitochondrial genes could be considered as an alternative to improve the sensitivity of B. bovis and B. bigemina detection using qPCR.

Epidemiology and molecular characterization of Theileria annulata in ticks collected from cattle in the central part of Tamil Nadu, India

Tick-borne diseases are the most common in cattle in the tropical and subtropical regions of India and lead to substantial economic losses to small and marginal farmers. This study aimed to identify the diverse species of ticks infesting cattle in the central part of Tamil Nadu, India, and to assess the prevalence of Theileria annulata infection in various species of ticks through PCR. Out of 123 cross-bred and 105 native breed cattle examined for tick infestation, 40 (18%) and 29 (12.7%) cattle were infested with Ixodid ticks, respectively. The most prevalent tick species identified was Rhipicephalus microplus (n=589), followed by Hyalomma anatolicum (n=532), Hyalomma marginatum (n=145), Haemaphysalis intermedia (n=79), and Rhipicephalus haemophysaloides (n=1) found in the study area. The prevalence and intensity of the tick infestation were found to be higher in cross-bred (71.04%) than native breed cattle (28.96%), and there was no significant difference between the studied breeds (chi-square value =24; df =20; p value =0.24) was observed. However, a significant difference in the H. anatolicum tick infestation was observed between the Cauvery Delta (14.30%) and the North-Western (20%) zones of Tamil Nadu (p<0.05). DNA fragments of 193 bp derived from 18S rRNA gene sequences of T. annulata were amplified using species-specific primers. Of these, 16 out of 37 (43.2%) and 10 out of 39 (29%) pooled samples of H. anatolicum and 4 out of 18 (22.2%) and 1 out of 5 (20%) pooled samples of H. marginatum were found positive for T. annulata from the Cauvery Delta and North-Western zones, respectively. R. microplus, H. intermedia, and R. haemaphysaloides from these regions were negative. These findings confirm that H. anatolicum (52.17%) is the predominant vector for T.annulata rather than H. marginatum (18.84%), and the PCR is a useful method of determining the infection rates in ticks collected from animals carrying low levels of T. annulata piroplasms.

THE FIRST SURVEY OF BOVINE BABESIA SPECIES INFECTING YAKS (BOS GRUNNIENS) IN MONGOLIA

Yak (Bos grunniens) farming is an important part of Mongolia's livestock industry. Yaks survive in harsh mountain environments; provide meat, milk, and wool; and serve as a mode of transportation. In Mongolia, yaks are frequently raised alongside other livestock animals such as cattle, Bactrian camels, sheep, goats, and horses. Recently, we demonstrated that Babesia bovis, Babesia bigemina, and Babesia naoakii-parasites with the potential to cause clinical bovine babesiosis-infect not only cattle but also Bactrian camels in Mongolia. However, yaks have never been surveyed for Babesia infections in this country. In the present study, we surveyed yaks in 8 Mongolian provinces: Bayankhongor, Bayan-Ulgii, Khovd, Khovsgol, Omnogovi, Ovorkhangai, Uvs, and Zavkhan. Blood samples were taken and deoxyribonucleic acid (DNA) was extracted from 375 yaks. Furthermore, Giemsa-stained thin smears were prepared from 315 of the 375 blood samples and then examined for the microscopic detection of Babesia parasites. Microscopy revealed that 34 (10.8%) of 315 blood smears were positive for Babesia parasites. All 375 DNA samples were then tested for B. bovis, B. bigemina, and B. naoakii infection using specific polymerase chain reaction assays. We observed that 238 (63.5%) yaks in all surveyed provinces and 8 (2.1%) yaks in 3 provinces (Bayankhongor, Bayan-Ulgii, and Omnogovi) were positive for B. bovis and B. bigemina, respectively. However, all yaks tested were negative for B. naoakii. This epidemiological survey, the first to report Babesia infection in Mongolian yaks, suggests that disease management strategies for yaks in this country should further address bovine babesiosis.

Global prevalence and species diversity of tick-borne pathogens in buffaloes worldwide: a systematic review and meta-analysis

BACKGROUND

Buffaloes are important contributors to the livestock economy in many countries, particularly in Asia, and tick-borne pathogens (TBPs) commonly infect buffaloes, giving rise to serious pathologies other than their zoonotic potential.

METHODS

The present investigation focuses on the prevalence of TBPs infecting buffaloes worldwide. All published global data on TBPs in buffaloes were collected from different databases (e.g., PubMed, Scopus, ScienceDirect, and Google Scholar) and subjected to various meta-analyses using OpenMeta[Analyst] software, and all analyses were conducted based on a 95% confidence interval.

RESULTS

Over 100 articles discussing the prevalence and species diversity of TBPs in buffaloes were retrieved. Most of these reports focused on water buffaloes (Bubalus bubalis), whereas a few reports on TBPs in African buffaloes (Syncerus caffer) had been published. The pooled global prevalence of the apicomplexan parasites Babesia and Theileria, as well as the bacterial pathogens Anaplasma, Coxiella burnetii, Borrelia, Bartonella, and Ehrlichia in addition to Crimean-Congo hemorrhagic fever virus, were all evaluated based on the detection methods and 95% confidence intervals. Interestingly, no Rickettsia spp. were detected in buffaloes with scarce data. TBPs of buffaloes displayed a fairly high species diversity, which underlines the high infection risk to other animals, especially cattle. Babesia bovis, B. bigemina, B. orientalis, B. occultans and B. naoakii, Theileria annulata, T. orientalis complex (orientalis/sergenti/buffeli), T. parva, T. mutans, T. sinensis, T. velifera, T. lestoquardi-like, T. taurotragi, T. sp. (buffalo) and T. ovis, and Anaplasma marginale, A. centrale, A. platys, A. platys-like and "Candidatus Anaplasma boleense" were all were identified from naturally infected buffaloes.

CONCLUSIONS

Several important aspects were highlighted for the status of TBPs, which have serious economic implications for the buffalo as well as cattle industries, particularly in Asian and African countries, which should aid in the development and implementation of prevention and control methods for veterinary care practitioners, and animal owners.

Detection of Babesia bovis using loop-mediated isothermal amplification (LAMP) with improved thermostability, sensitivity and alternative visualization methods

Bovine babesiosis is one of the most economically important tick-borne diseases in tropical and subtropical countries. A conventional microscopic diagnosis is typically used because it is inexpensive and expeditious. However, it is highly dependent on well-trained microscopists and tends to be incapable of detecting subpatent and chronic infections. Here, we developed a novel nucleic acid-based amplification method using loop-mediated isothermal amplification (LAMP) in conjunction with a colori-fluorometric dual indicator for the rapid and accurate detection of Babesia bovis based on the mitochondrial cytochrome b gene. We aimed to improve the thermostability, sensitivity, specificity, and alternative visualization of LAMP-based methods. We assessed its diagnostic performance compared to two conventional PCR agarose gel electrophoresis (PCR-AGE) methods. The thermostability of LAMP reaction mixtures and DNA templates in variable conditions was also assessed. In addition, we evaluated alternative visualization methods using different light sources including neon, LED, and UV lights. We found that the LAMP-neon was ten times more sensitive than the PCR-AGE, while the LAMP-LED and LAMP-UV were 1,000 times more sensitive. The current LAMP method showed no cross-amplification with uninfected cattle DNA or other common blood parasites in cattle, including Babesia bigemina, Theileria orientalis, Anaplasma marginale, and Trypanosoma evansi. In addition, the developed LAMP method has good thermostability and the potential for on-site utility as B. bovis DNA could still be detected up to 72 h after initial preparation. Our findings suggested that the developed LAMP method provides an alternative approach for B. bovis detection with sensitivity higher than PCR-AGE diagnostics, high specificity, and the flexibility to use neon, LED, and UV light sources for positive signal observations.

Molecular Identification of Babesia spp. and Anaplasma marginale in Water Buffaloes in Veracruz and Tabasco, Mexico: A Retrospective Study

Two hundred and thirty-three blood samples of water buffalo were collected on four farms in Veracruz state and Tabasco state, Mexico, to detect and confirm the identities of Babesia and Anaplasma spp. sequences. Nested PCR assays were used for the amplification of specific genes encoding B. bovis rhoptry-associated protein (RAP-1), B. bigemina SpeI-AvaI restriction fragment, and Anaplasma marginale major surface protein 5 (MSP5). Using DNA sequencing and BLASTn analysis for DNA homology hemoparasite identification, the identities of the hemoparasites were established by comparing the nucleotide sequences obtained in this study with those available in the GenBank database at the National Center for Biotechnology Information (NCBI). Water buffalo infection with at least one of the hemoparasites under study was detected in 45% (105/233) of the blood samples, while a mixed infection with B. bovis and B. bigemina was detected in 6.4% (15/233) of samples. For this cross-sectional study, mixed infections with the three hemoparasites were not detected. BLASTn analysis revealed that the nucleotide sequences of the water buffalo isolates shared sequence identity values ranging from 88 to 100% with previously published gene sequences of B. bovis, B. bigemina, and A. marginale. The current results confirm that water buffalo, as cattle, are also carriers of hemoparasite infections that are tick-transmitted, and suggest that they probably have an important role in the epidemiology of bovine babesiosis in Mexico.

Babesiosis and Theileriosis in North America

Babesia and Theileria are apicomplexan parasites that cause established and emerging diseases in humans, domestic and wild animals. These protozoans are transmitted by Ixodid ticks causing babesiosis or theileriosis, both characterized by fever, hemolytic anemia, jaundice, and splenomegaly. In North America (NA), the most common species affecting humans is B. microti, which is distributed in the Northeastern and Upper Midwestern United States (US), where the tick vector Ixodes scapularis is established. In livestock, B. bovis and B. bigemina are the most important pathogens causing bovine babesiosis in tropical regions of Mexico. Despite efforts toward eradication of their tick vector, Rhipicephalus microplus, B. bovis and B. bigemina present a constant threat of being reintroduced into the southern US and represent a continuous concern for the US cattle industry. Occasional outbreaks of T. equi, and T. orientalis have occurred in horses and cattle, respectively, in the US, with significant economic implications for livestock including quarantine, production loss, and euthanasia of infected animals. In addition, a new species, T. haneyi, has been recently discovered in horses from the Mexico-US border. Domestic dogs are hosts to at least four species of Babesia in NA that may result in clinical disease that ranges from subclinical to acute, severe anemia. Herein we review the pathogenesis, diagnosis, and epidemiology of the most important diseases caused by Babesia and Theileria to humans, domestic and wild animals in Canada, the US, and Mexico.

Harnessing Mycobacterium bovis BCG Trained Immunity to Control Human and Bovine Babesiosis

Babesiosis is a disease caused by tickborne hemoprotozoan apicomplexan parasites of the genus Babesia that negatively impacts public health and food security worldwide. Development of effective and sustainable vaccines against babesiosis is currently hindered in part by the absence of definitive host correlates of protection. Despite that, studies in Babesia microti and Babesia bovis, major causative agents of human and bovine babesiosis, respectively, suggest that early activation of innate immune responses is crucial for vertebrates to survive acute infection. Trained immunity (TI) is defined as the development of memory in vertebrate innate immune cells, allowing more efficient responses to subsequent specific and non-specific challenges. Considering that Mycobacterium bovis bacillus Calmette-Guerin (BCG), a widely used anti-tuberculosis attenuated vaccine, induces strong TI pro-inflammatory responses, we hypothesize that BCG TI may protect vertebrates against acute babesiosis. This premise is supported by early investigations demonstrating that BCG inoculation protects mice against experimental B. microti infection and recent observations that BCG vaccination decreases the severity of malaria in children infected with Plasmodium falciparum, a Babesia-related parasite. We also discuss the potential use of TI in conjunction with recombinant BCG vaccines expressing Babesia immunogens. In conclusion, by concentrating on human and bovine babesiosis, herein we intend to raise awareness of BCG TI as a strategy to efficiently control Babesia infection.

Serosurveillance and risk factors for Neospora caninum infection in water buffaloes (B. bubalis) from central and southern Mexico

The water buffalo (B. bubalis) is an alternative to cattle ranching in several regions of southern Mexico. Here we report seroprevalence and risk factors associated with the protozoan parasite, Neospora caninum, in water buffaloes in six buffalo production units, in municipalities from central and southern Veracruz, Mexico. Antibodies to N. caninum were assessed in serum samples of 543 buffaloes by a commercial ELISA-kit, and 44.8% (243/543; 95% CI 40.5-49.0) were seropositive. Questionnaires were used to collect epidemiological data and to identify risk factors associated with N. caninum infection. Data analysis indicated that older buffaloes (≥7 year) exhibited the highest seroprevalence for neosporosis 62.3% (38/61; 95% CI 49.7-73.4) (P ≤ 0.05). Buffaloes that were in close contact with cattle had higher seroprevalence 47.6% (168/353; 95% CI 42.3-52.9) (P < 0.01) than those that were not in contact 36.8% (70/190; 95% CI 30.0-44.1). Our findings provide important information to implement preventive measures in the buffalo farms.

Detection of Babesia spp. in High Altitude Cattle in Ecuador, Possible Evidence of the Adaptation of Vectors and Diseases to New Climatic Conditions

Background: Babesia species are intraerythrocytic protozoa, distributed in tropical and subtropical areas of the world, causing anemic diseases in many animals, including cattle. This disease, called babesisosis, is transmitted from one animal to another through ticks (Tick Borne-Disease or TBD). On the other hand, Ecuador has a tropical climate that allows the development of the vector Rhipicephalus microplus, and therefore favors the transmission of Babesia spp. in cattle. Methods and principal findings: We determined the presence of Babesia spp. by PCR using 18s ribosomal gene as target (18s PCR) in 20 farms in the area of El Carmen (zone below 300 m above sea level) and 1 farm in Quito (2469 m.a.s.l.). In addition, we analyzed parameters such as age, sex, and packed cell volume (PCV) as explanatory variable associated with the disease. Results: The 18s PCR test showed that 18.94% (14.77% Babesia bovis and 4.17% Babesia bigemina) and 20.28% (14.69% B. bovis and 5.59% B. bigemina) of the cattle were positive for Babesia spp in farms sampled in El Carmen and in Quito, respectively. Age influenced the presence of animals positive for Babesia spp., but sex and PCV did not. The phylogenetic analysis of sequences showed 4 isolates of B. bovis and 3 isolates of B. bigemina in the 2 study zones, with similarities between 99.73 and 100% with other sequences. One B. bovis isolate was similar in the zone of El Carmen and Quito. Conclusion and significance: This work is the first molecular characterization of B. bigemina and B. bovis in Ecuador, and it is also the first evidence of Babesia spp. in cattle in the area of Quito at an altitude of 2469 m.a.s.l., being the highest altitude reported for animals with babesiosis and for the tick R. microplus. Climatic factors as well as mobility of tick-carrying animals without any control allow the presence of Babesiosis outbreaks in new geographical areas.

Gap Analysis of the Habitat Interface of Ticks and Wildlife in Mexico

Mexico is a highly diverse country where ticks and tick-borne diseases (TBD) directly impact the health of humans and domestic and wild animals. Ticks of the genera Rhipicephalus spp., Amblyomma spp., and Ixodes spp. represent the most important species in terms of host parasitism and geographical distribution in the country, although information on other genera is either limited or null. In addition, information regarding the influence of global warming on the increase in tick populations is scarce or nonexistent, despite climate conditions being the most important factors that determine tick distribution. In order to aid in the management of ticks and the risks of TBD in humans and domestic animals in Mexico, an analysis was conducted of the gaps in information on ticks with the purpose of updating the available knowledge of these ectoparasites and adapting the existing diagnostic tools for potential distribution analysis of TBD in wildlife. These tools will help to determine the epidemiological role of wildlife in the human–domestic animal interface in anthropized environments in Mexico.

Molecular survey of bovine Babesia species in Bactrian camels (Camelus bactrianus) in Mongolia

Bovine babesiosis, which is caused by species of genus Babesia, is a leading cause of considerable economic losses to the cattle industry each year. Bovine Babesia species have frequently been detected in non-cattle hosts, such as water buffalo (Bubalus bubalis), from which the parasites can be transmitted by ticks to cattle. Therefore, Babesia infections should be minimized not only in cattle but also in non-cattle carriers. In the present study, we surveyed the Bactrian camels (Camelus bactrianus) in Mongolia for three clinically significant bovine Babesia species, including Babesia bovis, B. bigemina, and Babesia sp. Mymensingh, which had been detected previously in Mongolian cattle. We screened blood DNA samples from 305 Bactrian camels in six Mongolian provinces for these species, using parasite-specific PCR assays. Our findings showed that the Bactrian camels in Mongolia were infected with all three Babesia species surveyed. The overall positive rates of B. bovis, B. bigemina, and Babesia sp. Mymensingh were 32.1%, 21.6%, and 24.3%, respectively, whereas 52.5% of the surveyed animals were infected with at least one parasite species. We also found that the female Bactrian camels and the Mongolian native camel breed had significantly higher Babesia positive rates than the male Bactrian camels and the Hos Zogdort breed. In Mongolia, cattle and Bactrian camels usually share common pasture lands for grazing; furthermore, tick species infesting cattle also infest Bactrian camels. Our findings, together with these observations, suggest that the tick transmission of bovine Babesia species might be possible between cattle and Bactrian camels. Therefore, strategies for the control of bovine babesiosis in Mongolia should include methods to minimize bovine Babesia species infections in Bactrian camels.

Comparative Study of Indirect Fluorescent Antibody, ELISA, and Immunochromatography Tests for Serological Diagnosis of Bovine Babesiosis Caused by Babesia bovis

Simple Summary

Currently serological diagnosis of bovine babesiosis is based on the detection of Babesia-specific antibodies (immunoglobulin-G). Antibody detection is commonly used in seroepidemiological studies or in the assessment of antibabesial antibody titers after cattle vaccination. The indirect fluorescent antibody test (IFAT) and enzyme-linked immunosorbent assay (ELISA) are the most widely used diagnostic tests, although there their implementation has some drawbacks, principally due to the requirements for trained personnel, specific materials, and special laboratory equipment. This study compared a newly designed rapid immunochromatography test (ICT), which has been reported recently and used for Babesia bovis-specific antibody detection with promising results, with an in-house ELISA for the serological diagnosis of cattle exposed to B. bovis (Babesia bovis) in Mexico. Higher sensitivity and specificity values were found by ICT, proving its effectiveness over ELISA. ICT also had better concordance than ELISA when IFAT was used as the “gold standard”. The rapid ICT was shown to have diagnostic utility for the detection of antibodies against B. bovis and could be used as a field test in Mexico due to its practicality, as it does not need laboratory equipment for implementation and interpretation of results.

Abstract

The indirect fluorescent antibody test (IFAT) is the most frequently used test to conduct seroepidemiological studies so far, and it is regarded as the "gold standard" test for the serological diagnosis of bovine babesiosis. The aim of the present study was to compare the enzyme-linked immunosorbent assay (ELISA) and the rapid immunochromatography test (ICT) for use in the serological diagnosis of cattle exposed to B. bovis in Mexico. The evaluation of test performance was carried out with 30 positive and 30 negative reference sera. A total of 72 bovine sera samples collected from cattle in a region with endemic bovine babesiosis were analyzed by ELISA and ICT, and the results were compared with those of IFAT. Kappa value (k) was also calculated to determine the agreement between tests. The sensitivity and specificity of ELISA for detecting antibodies against B. bovis were 87% (26/30) and 80% (24/30), respectively. The sensitivity and specificity of ICT for detecting antibodies against B. bovis were 90% (27/30) and 83.3% (25/30), respectively. The overall concordance determined for ELISA and ICT was 94.4% (68/72) and 98.6% (71/72), respectively, when the results were compared with those of IFAT. ICT was more sensitive and specific in this comparative study, showing good strength of agreement (k = 0.79) with respect to IFAT. ICT combines a strip-based assay system that is fast, practical, and sensitive for detection of antibodies to B. bovis, which suggests that it could be applied in the field without requiring any laboratory equipment for its use and interpretation of test results.

First detection of Anaplasma phagocytophilum and Babesia divergens and high infection rates of Anaplasma marginale and Babesia bigemina in cattle in extensive grazing systems of Central Spain

Bovine vector-borne diseases have a considerable economic impact worldwide and affect health of humans and animals. However, different aspects of their epidemiology and their pathogenesis remain unclear. Despite the frequent description of clinical cases reported by practitioners attending cattle from Madrid, Central Spain, molecular prevalence of Anaplasma spp. and Babesia spp. has not been described. The aim of this study was to assess the positivity rate of A. phagocytophilum, A. marginale, A. centrale, B. bigemina and B. divergens in livestock of this area and to evaluate the existence of associations between these pathogens and haematological, biochemical and epidemiological data. Babesia divergens and A. phagocytophilum were detected for the first time in cattle from Madrid. Their positivity percentages were low (2.2% ± 1.4% and 1.8% ± 1.2%, respectively), but this description is of special interest, as these agents are potentially zoonotic. Both agents were found in areas of higher altitude and relative humidity and lower temperature. The detection of ticks in livestock during the moment of sampling was confirmed as a risk factor for these infections. Anaplasma marginale showed the highest molecular infection rate (30% ± 4.1%) in this study, followed by B. bigemina (21.9% ± 3.7%). Higher positivity rates of A. marginale and B. bigemina were found in the areas of mountain climate and warm-summer continental Mediterranean climate. The use of ectoparasiticide treatment was found as a risk factor for infection by A. marginale and B. bigemina. This finding could lead to reconsider the ectoparasiticide protocols that are used nowadays. Grazing on pastures with domestic or wild ruminants and the presence of wild carnivores were associated with higher rates of infection by these four agents and coinfections were frequently found.

Mitochondrial genome of Theileria uilenbergi endemic in sheep and goats in China

Mitochondrial genomes provide new insights that help elucidating biological features, genetic evolution, and classification of protozoans. Theileria uilenbergi (T. uilenbergi), transmitted by Haemaphysalis qinghaiensis and H. longicornis, is considered as highly pathogenic to sheep and goats in China. This study reports and outlines features of its mitochondrial genome. The T. uilenbergi mitochondrial genome is a linear monomeric molecule of 6.0 kb length, which encodes three protein-coding genes named cytochrome c oxidase I (cox1), cytochrome b (cob), and cytochrome c oxidase III (cox3), as well as six large subunit (LSU) rRNA gene fragments, and ends in terminal inverted repeats (TIRs). The array structure and organization of the mitochondrial genome of T. uilenbergi is identical to that of T. parva. Phylogenetic analysis based on the amino acid sequences of cox1, cob, and cox3 genes suggests that T. uilenbergi is distantly related to the group of transforming Theileria species such as T. parva. This study contributes to a comprehensive understanding of the phylogeny and evolution of the mitochondrial genome of piroplasms and provides useful information of diagnostic marker for T. uilenbergi.

Semi-quantitative evaluation of Babesia bovis and B. bigemina infection levels estimated by HRM analysis

Bovine babesiosis is economically the most important arthropod-borne disease of cattle worldwide. The most significant damage caused by bovine babesiosis is attributed to Babesia bovis due to its higher pathogenicity. This study aimed to develop a real-time PCR method followed by HRM (high-resolution melting) analysis for the simultaneous detection of B. bovis and B. bigemina, enabling a semi-quantitative analysis of Babesia levels using a single-tube reaction. The HRM was compared with real-time PCR using species-specific hydrolysis probes. The HRM analysis allowed to differentiate both Babesia species and was sensitive in the detection and differentiation of 10% for each Babesia species in the sample. Our results suggest the use of this method to estimate the prevalence of infections by B. bovis or B. bigemina as an alternative to the methods of absolute quantification by real-time PCR since it neither requires precise estimates of the number of DNA loads nor the construction of calibration curves. The simultaneous detection of the two Babesia species can be used to characterise the infection levels in cattle populations from different geographical regions, allowing a better control of these diseases.

Morphometrics of Amblyomma mixtum in the State of Veracruz, Mexico

The tick Amblyomma mixtum is an ectoparasite of veterinary and public health importance because of its role as a vector of zoonotic pathogens. However, little is known about A. mixtum intraspecific variability and if morphological differentiation exists between populations across its geographic range. This study aimed to determine by electron microscopy the morphological variability of A. mixtum populations in the state of Veracruz, which has a large livestock population among states in Mexico. Forty male and 40 female A. mixtum collected from the 10 natural regions of Veracruz state were analyzed microscopically to accomplish main component analysis for each sex. Clusters were calculated with the out-tree method and a dendrogram produced to group the specimens according to their morphometric characteristics. Using 10 main components, 77% of the morphological variation of the ticks was explained. This is a reflection of scarce intraspecific variation between females. The dendogram for females grouped six clusters of specimens with similar characteristics. Morphometric variability in males was described using eight main components. Limited intraspecific variation was also observed between males. In males, the dendogram yielded six groups with similar morphometric characteristics. Morphometric analyses confirmed that the only species from the Amblyomma cajennense complex that are parasites to livestock in Veracruz state is A. mixtum. The eryxenous nature of A. mixtum combined with the frequent movement of livestock hosts may contribute to the apparent homogeneous phenotype of this tick species in Mexico.

Stray Mexico origin cattle captured crossing into Southern Texas carry Babesia bovis and other tick-borne pathogens

Cattle fever ticks, Rhipicephalus microplus and R. annulatus have been eradicated from the United States and inspectors from the U.S. Department of Agriculture (USDA), Animal Plant Health Inspection Service (APHIS), Cattle Fever Tick Eradication Program (CFTEP) monitor the quarantine zone along the Texas border to prevent the introduction of livestock carrying cattle fever ticks from Mexico. Stray livestock apprehended by CFTEP in the zone are checked for ticks and tested for infectious disease-causing pathogens but are not evaluated for evidence of infection with tick-borne pathogens. We tested blood samples collected from stray cattle by CFTEP inspectors for evidence of infection with tick-borne pathogens. As a comparison group representing U.S. resident cattle, we tested blood samples that had been sent to the Texas A&M Veterinary Medical Diagnostic Laboratory (TVMDL) for unrelated testing. Both sets of blood samples were evaluated using the same specific and broad-spectrum PCR assays. For the border cattle the overall prevalence of infection with one or more tick-borne pathogen was 58.5 % (79/135) with many co-infections, including 30 cattle positive for Babesia bovis and/or Babesia bigemina (22.2 %) and 77 cattle positive for Anaplasma marginale (57 %), three of these animals were also positive for Borrelia theileri. No resident cattle represented by the TVMDL samples were infected with either of the Babesia spp., or with Borrelia theileri, but three were positive for Theileria orientalis and 7.3 % (7/96) were positive for A. marginale. These data show that cattle originating in Mexico have a higher prevalence of infection with tick-borne pathogens relative to resident U.S. cattle and specifically, a proportion are infected with bovine Babesia, which is absent from U.S. cattle populations. Consequently, these stray cattle may be a reservoir of tick-borne pathogens and if populations of Boophilus ticks become reestablished in areas where they had previously been eradicated, could pose a significant risk to the U.S. Cattle industry.

Research on Integrated Management for Cattle Fever Ticks and Bovine Babesiosis in the United States and Mexico: Current Status and Opportunities for Binational Coordination

Bovine babesiosis is a reportable transboundary animal disease caused by Babesia bovis and Babesiabigemina in the Americas where these apicomplexan protozoa are transmitted by the invasive cattle fever ticks Rhipicephalus (Boophilus) microplus and Rhipicephalus(Boophilus) annulatus. In countries like Mexico where cattle fever ticks remain endemic, bovine babesiosis is detrimental to cattle health and results in a significant economic cost to the livestock industry. These cattle disease vectors continue to threaten the U.S. cattle industry despite their elimination through efforts of the Cattle Fever Tick Eradication Program. Mexico and the U.S. share a common interest in managing cattle fever ticks through their economically important binational cattle trade. Here, we report the outcomes of a meeting where stakeholders from Mexico and the U.S. representing the livestock and pharmaceutical industry, regulatory agencies, and research institutions gathered to discuss research and knowledge gaps requiring attention to advance progressive management strategies for bovine babesiosis and cattle fever ticks. Research recommendations and other actionable activities reflect commitment among meeting participants to seize opportunities for collaborative efforts. Addressing these research gaps is expected to yield scientific knowledge benefitting the interdependent livestock industries of Mexico and the U.S. through its translation into enhanced biosecurity against the economic and animal health impacts of bovine babesiosis and cattle fever ticks.

First detection of Anaplasma ovis in sheep and Anaplasma platys-like variants from cattle in Menoufia governorate, Egypt

Tick-borne diseases are of global economic importance, especially due to the costs associated with disease treatment and productivity losses in livestock. In this study, 244 livestock animals (cattle N = 92, buffaloes N = 86 and sheep N = 66) from Menoufia, Egypt were tested for Anaplasma, Ehrlichia and Babesia species using PCR. Results revealed detection of A. ovis (9.1%) in sheep while Anaplasma spp. (14.1%), A. marginale (15.2%), B. bigemina (6.5%) and B. bovis (5.4%) in cattle. On the other hand, Anaplasma spp. (1.2%), A. marginale (1.2%) and B. bovis (1.2%), were detected in buffaloes. Significantly higher detection rates were observed in cattle for Anaplasma spp. (P = .020), A. marginale (P = .001) and B. bigemina (P = .022) than in buffaloes. Sequence analysis of Anaplasma spp. isolates from cattle, revealed A. platys-like strains. Phylogenetic analyses of the A. platys-like isolates revealed variation among the strains infecting cattle. The A. marginale buffalo isolate, on the other hand, showed some level of divergence from the cattle isolates. This study reports the first detection of A. ovis in sheep and A. platys-like strains in cattle in Menoufia and Egypt at large. The results of the current study provide valuable information on the epidemiology and genetic characteristics of tick-borne pathogens infecting livestock in Egypt.

Efficient Transovarial Transmission of Babesia Spp. in Rhipicephalus microplus Ticks Fed on Water Buffalo (Bubalus bubalis)

Water buffaloes can be infected by tick-borne pathogens (TBPs) in endemic areas where cattle and buffalo coexist. Among TBPs affecting buffaloes is the Apicomplexan hemoparasites Babesia bovis and B. bigemina, transmitted by Rhipicephalus microplus ticks. However, little empirical evidence exists on whether buffalo can support TBPs’ infection and transmission. A cohort study was designed to measure the infestation levels of R. microplus in buffaloes as well as the ability of buffalo-fed ticks to transmit B. bovis and B. bigemina to their offspring. Tick infestation of different life stages was quantified in cattle and buffalo kept in field conditions in western Cuba. Engorged adult female ticks were allowed to lay eggs in controlled conditions of humidity and temperature, and reproductive parameters were measured and analyzed. Hosts and tick larvae were tested for the presence of Babesia spp. using species-specific qPCR assays. Tick infestation was not observed in adult buffaloes. However, buffalo and cattle calves were equally infested, although the larval survival rate was higher in cattle calves than in buffalo calves. All larval pools (31) obtained from the adult female ticks were positive for B. bovis, whereas only 68% (21/31) was positive for B. bigemina. Among the 10 larval pools negative for B. bigemina, three proceeded from adult females fed on Babesia-negative buffaloes. The other seven pools were from Babesia-positive animals, three from cattle and four from buffalo calves. Babesia infection levels in tick larvae, quantified by qPCR, were similar in female ticks fed on buffalo and bovine calves. We conclude that water buffalo can sustain tick vector populations and support Babesia infection in levels high enough as to be infective for ticks. Our results also validated the hypothesis that adult female ticks fed on buffalo can transmit the pathogens B. bovis and B. bigemina to their offspring. Nevertheless, further laboratory studies are needed to address the question of whether the transovarial transmission of Babesia occurs in the following settings: (1) When adult females are infected previous to the feeding on the buffalo or/and (2) when the adult females acquire the infection while feeding on the buffalo.

Characterization of cattle tick fever in calves from the northwestern region of Minas Gerais, Brazil

The present study aimed to characterize the importance of the Anaplasma marginale, Babesia bovis and Babesia bigemina in the genesis of cattle tick fever (CTF) among dairy calves in the northwest of Minas Gerais, Brazil. Blood samples from 300 calves were collected, followed by DNA extraction and nested PCR using oligonucleotide primers to amplify fragments of the semi-nested for the msp5 gene (A. marginale), sbp-4 (B. bovis) and rap-1a (B. bigemina) Among the examined calves, the prevalence of A. marginale was 55.6% (n=167/300), B. bovis was 4.0% (n=12/300) and B. bigemina was 15.3% (n=46/300), by PCR techniques. Parasitic forms of A. marginale and B. bigemina were found in 36,3% and 2,6% of the blood smears while B. bovis was not detected. There was a statistical difference between the positivity of infected animals in the age groups 1 (10-70 days) and (>70-300 days) for A. marginale and B. bigemina. A total of 15 calves with the classic symptoms of disease were examined, and the samples obtained were confirmed as a simple infection by A. marginale through semi-nested PCR. These results confirm bovine anaplasmosis as the primary cause of CTF among the calves of dairy cattle within the studied area.

Highly sensitive nested PCR and rapid immunochromatographic detection of Babesia bovis and Babesia bigemina infection in a cattle herd with acute clinical and fatal cases in Argentina

Bovine babesiosis is a tick-transmitted haemoparasitic disease caused by Babesia bovis and B. bigemina affecting cattle of tropical and subtropical regions around the world. Pathogens are transmitted by the tick vector Rhipicephalus microplus displaying a widespread distribution in northeastern Argentina. The disease is characterized by significant animal morbidity and mortality resulting in considerable economic loss. In this study, B. bovis and B. bigemina infection was investigated in a cattle herd of 150 adult bovines of pure Braford breed raised in a tick-hyperendemic field using molecular and serum antibody tests. A highly sensitive nested polymerase chain reaction (nPCR) assay targeting a species-specific region of the apocytochrome b gene resulted in direct B. bovis and B. bigemina detection in 27.3% and 54.7% of bovines, respectively. A recently developed immunochromatographic strip test (ICT) based on recombinant forms of spherical body protein 4 and the C-terminal region of rhoptry-associated protein 1 showed that 71.3% and 89.3% of bovines were seropositive for B. bovis and B. bigemina, respectively. The mixed infection rate as observed by direct (19.3%) and indirect detection (65.3%) coincided with those expected, respectively. Importantly, four months after sampling, nine bovines of the studied herd showed clinical signs of bovine babesiosis of which six animals eventually died. Microscopic detection of infected erythrocytes in Giemsa-stained blood smears confirmed B. bovis infection. Our study demonstrates that although animals showed a relatively high and very high rate of immunity against infection with B. bovis (71.3%) and B. bigemina (89.3%) parasites, respectively, clinical cases and fatalities due to the infection with B. bovis were observed. It is proposed that the most adequate control measure in the studied epidemiological situation is to vaccinate animals to prevent losses and/or an outbreak of bovine babesiosis.

Diagnostic Tools for the Identification of Babesia sp. in Persistently Infected Cattle

Bovine babesiosis is a tick-borne disease of cattle caused by the protozoan parasites of the genus Babesia. Babesia bovis, Babesia bigemina and Babesia divergens are considered by International health authorities (OIE) as the principal species of Babesia that cause bovine babesiosis. Animals that recover from a babesial primo infection may remain as persistent carriers with no clinical signs of disease and can be the source of infection for ticks that are able to acquire Babesia parasites from infected cattle and to transmit Babesia parasites to susceptible cattle. Several procedures that have been developed for parasite detection and diagnosis of this infectious carrier state constitute the basis for this review: A brief description of the direct microscopic detection of Babesia-infected erytrocytes; PCR-based diagnostic assays, which are very sensitive particularly in detecting Babesia in carrier cattle; in-vitro culture methods, used to demonstrate presence of carrier infections of Babesia sp.; animal inoculation, particularly for B. divergens isolation are discussed. Alternatively, persistently infected animals can be tested for specific antibabesial antibodies by using indirect serological assays. Serological procedures are not necessarily consistent in identifying persistently infected animals and have the disadvantage of presenting with cross reactions between antibodies to Babesia sp.

High co-infection rates of Babesia bovis, Babesia bigemina, and Anaplasma marginale in water buffalo in Western Cuba

Water buffalo is important livestock in several countries in the Latin American and Caribbean regions. This buffalo species can be infected by tick-borne hemoparasites and remains a carrier of these pathogens which represent a risk of infection for more susceptible species like cattle. Therefore, studies on the epidemiology of tick-borne hemoparasites in buffaloes are required. In this study, the prevalence of Babesia bovis, Babesia bigemina, and Anaplasma marginale were determined in water buffalo herds of western Cuba. To this aim, a cross-sectional study covering farms with large buffalo populations in the region was performed. Eight buffalo herds were randomly selected, and blood samples were collected from 328 animals, including 63 calves (3-14 months), 75 young animals (3-5 years), and 190 adult animals (> 5 years). Species-specific nested PCR and indirect ELISA assays were used to determine the molecular and serological prevalences of each hemoparasite, respectively. The molecular and serological prevalence was greater than 50% for the three hemoparasites. Differences were found in infection prevalence among buffalo herds, suggesting that local epidemiological factors may influence infection risk. Animals of all age groups were infected, with a higher molecular prevalence of B. bigemina and A. marginale in young buffalo and calves, respectively, while a stepwise increase in seroprevalence of B. bovis and B. bigemina from calves to adult buffaloes was found. The co-infection by the three pathogens was found in 12% of animals, and when analyzed by pair, the co-infections of B. bovis and B. bigemina, B. bigemina and A. marginale, and B. bovis and A. marginale were found in 20%, 24%, and 26%, respectively, underlying the positive interaction between these pathogens infecting buffaloes. These results provide evidence that tick-borne pathogen infections can be widespread among water buffalo populations in tropical livestock ecosystems. Further studies should evaluate whether these pathogens affect the health status and productive performance of water buffalo and infection risk of these pathogens in cattle cohabiting with buffalo.

Serological and molecular prevalence of equine piroplasmosis in Western Java, Indonesia

Equine piroplasmosis is an economically significant disease caused by Theileria equi and Babesia caballi, which are tick-borne hemoprotozoan parasites. Infections with these parasite species had never been reported in horses in Indonesia. The aim of the present study was to investigate the prevalence of T. equi and B. caballi in horses reared in parts of Western Java, Indonesia. Blood samples were collected randomly from 235 horses in four different districts (Bandung, Depok, Tangerang, and Bogor) in Western Java, Indonesia. Thin blood smears prepared from the sampled animals were stained by Giemsa and observed under a light microscope. Serum samples prepared from blood were screened by enzyme-linked immunosorbent assays (ELISAs) based on recombinant forms of EMA-2 and BC48 antigens to determine the seroprevalence of T. equi and B. caballi, respectively. DNA samples extracted from the same blood samples were screened by EMA-2 and BC48 gene-based nested polymerase chain reaction (nPCR) assays for T. equi and B. caballi infections, respectively. Of 235 surveyed animals, five (2.1%) and 15 (6.4%) were seropositive for T. equi and B. caballi, respectively, whereas one and four horses were nPCR-positive for T. equi and B. caballi, respectively. All of the surveyed animals were negative for T. equi and B. caballi by microscopy. The T. equi EMA-2 and B. caballi BC48 gene fragments amplified by the nPCR assays were cloned, sequenced, and subjected to bioinformatic and phylogenetic analyses. The T. equi EMA-2 gene sequence from an Indonesian horse was identical to sequences from Florida and Washington strains and clustered together with these sequences in phylogeny. On the other hand, four Indonesian BC48 gene sequences shared 99.8-100% identity scores. This present study is the first to report T. equi and B. caballi in horses in Indonesia. Our findings highlight the need for monitoring horses in Indonesia for clinical piroplasmosis caused by T. equi and B. caballi.

Mitigated clinical disease in water buffaloes experimentally infected with Babesia bovis

Water buffaloes (Bubalus bubalis) are raised in tropical and subtropical regions of the world, and act as hosts of Babesia bovis parasites and the tick vector Rhipicephalus microplus. As no clinical cases of B. bovis-infection have been reported, we hypothesized that, unlike bovines, water buffaloes respond asymptomatically to an acute infection. To test this hypothesis, we inoculated two groups of 24-month-old Mediterranean breed water buffaloes with 10⁸ erythrocytes infected with two Argentine B. bovis isolates: BboM2P (n = 5) or BboS2P (n = 5). These strains displayed mild (BboM2P) or high (BboS2P) pathogenicity in Bos taurus calves of the same age (n = 5 and n = 1, respectively), when tested in parallel. In water buffaloes, no changes in body temperature were observed with both strains, and no hematocrit changes were detected in BboM2P-inoculated animals. In contrast, in the BboS2P-inoculated water buffalo group significant but relatively minor reductions in haematocrit values were noted compared to the infected bovine. The parasitemia attained in water buffaloes was considerably lower than in bovines and could only be detected by nested PCR, or indirectly via serology, whereas in most bovines, it could also be detected in Giemsa-stained smears under the light microscope. Our results show that water buffaloes present no or significantly mitigated clinical symptoms to B. bovis infections and suggest that they are able to substantially reduce and/or eliminate B. bovis parasites from circulation by an efficient innate immune mechanism.

Development and validation of a duplex real-time PCR assay for the diagnosis of equine piroplasmosis

Background

Equine piroplasmosis (EP) is an economically significant infection of horses and other equine species caused by the tick-borne protozoa Theileria equi and Babesia caballi. The long-term carrier state in infected animals makes importation of such subclinical cases a major risk factor for the introduction of EP into non-enzootic areas. Regulatory testing for EP relies on screening of equines by serological methods. The definitive diagnosis of EP infection in individual animals will benefit from the availability of sensitive direct detection methods, for example, when used as confirmatory assays for non-negative serological test results. The objectives of this study were to develop a real-time quantitative polymerase chain reaction (qPCR) assay for simultaneous detection of both agents of EP, perform comprehensive evaluation of its performance and assess the assay’s utility for regulatory testing.

Results

We developed a duplex qPCR targeting the ema-1 gene of T. equi and the 18S rRNA gene of B. caballi and demonstrated that the assay has high analytical sensitivities for both piroplasm species. Validation of the duplex qPCR on samples from 362 competitive enzyme-linked immunosorbent assay (cELISA)-negative horses from Canada and the United States yielded no false-positive reactions. The assay’s performance was further evaluated using samples collected from 430 horses of unknown EP status from a highly endemic area in Brazil. This set of samples was also tested by a single-target 18S rRNA qPCR for T. equi developed at the OIE reference laboratory for EP in Japan, and a previously published single-target 18S rRNA qPCR for B. caballi whose oligonucleotides we adopted for use in the duplex qPCR. Matching serum samples were tested for antibodies to these parasites using cELISA. By the duplex qPCR, T. equi-specific 18S rRNA qPCR and cELISA, infections with T. equi were detected in 87.9% (95% confidence interval, CI: 84.5–90.7%), 90.5% (95% CI: 87.3–92.3%) and 87.4% (95% CI: 84.0–90.2%) of the horses, respectively. The B. caballi prevalence estimates were 9.3% (95% CI: 6.9–12.4%) by the duplex qPCR and 7.9% (95% CI: 5.7–10.9%) by the respective single-target qPCR assay. These values were markedly lower compared to the seroprevalence of 58.6% (95% CI: 53.9–63.2%) obtained by B. caballi-specific cELISA. The relative diagnostic sensitivity of the duplex qPCR for T. equi was 95.5%, as 359 of the 376 horses with exposure to T. equi confirmed by cELISA had parasitemia levels above the detection limit of the molecular assay. In contrast, only 39 (15.5%) of the 252 horses with detectable B. caballi-specific antibodies were positive for this piroplasm species by the duplex qPCR.

Conclusions

The duplex qPCR described here performed comparably to the existing single-target qPCR assays for T. equi and B. caballi and will be more cost-effective in terms of results turnaround time and reagent costs when both pathogens are being targeted for disease control and epidemiological investigations. These validation data also support the reliability of the ema-1 gene-specific oligonucleotides developed in this study for confirmatory testing of non-negative serological test results for T. equi by qPCR. However, the B. caballi-specific qPCR cannot be similarly recommended as a confirmatory assay for routine regulatory testing due to the low level of agreement with serological test results demonstrated in this study. Further studies are needed to determine the transmission risk posed by PCR-negative equines with detectable antibodies to B. caballi.

Seroepidemiology of Infection with Neospora Caninum, Leptospira, and Bovine Herpesvirus Type 1 in Water Buffaloes (Bubalus Bubalis) in Veracruz, Mexico

We aimed to determine the seroprevalence of infection with Neospora caninum, Leptospira, and bovine herpesvirus type 1 and risk factors associated with these infections in water buffaloes in Veracruz State, Mexico. Through a cross-sectional study, 144 water buffaloes (Bubalus bubalis) raised in 5 ranches of Veracruz were examined for anti-N. caninum and anti-bovine herpesvirus type 1 antibodies by enzyme immunoassays, and anti-Leptospira interrogans antibodies by microscopic agglutination test.

Of the 144 buffaloes studied, 35 (24.3%) were positive for N. caninum, 50 (34.7%) for Leptospira, and 83 (57.6%) for bovine herpes virus. The frequencies of leptospiral serovars in buffaloes were as follows: 18.7% for Muenchen (n = 27), 10.4% for Hardjo LT (n = 15), 9.0% for Pyrogenes (n = 13), and 4.8% for Icterohaemorrhagiae (n = 7). Seropositive buffaloes were found in all 5 ranches studied. Logistic regression showed that cohabitation of buffaloes with cows was associated with infection with Leptospira (odds ratio [OR], 2.2; 95% confidence interval [CI], 1.04–4.5; P = 0.03) and bovine herpesvirus (OR, 12.0; 95% CI, 4.0–36.2; P < 0.01).

This is the first study that provides serological evidence of N. caninum, Leptospira, and bovine herpesvirus type 1 infections in water buffaloes in Mexico. Our findings could be used to enhance preventive measures against these infections.

Study of gastrointestinal parasites in water buffalo (Bubalus bubalis) reared under Mexican humid tropical conditions

The objective was to determine the frequency of gastrointestinal parasites (GP) genera affecting water buffalo (Bubalus bubalis) reared under humid tropical conditions of Mexico. Three hundred eighty-three Munrah breed water buffalo were included, 251 adult females and 132 calves. Feces were directly collected form the rectum of the animals and processed by the McMaster technique. Coprocultures were made to identify the genera of the nematodes. The frequency of GP in B. bubalis was 42%, independently of their age, 60% of calves resulted parasitized. Age had a strong association with the presence of GP (Xi² = 77.4014, d.f. = 1, p = 0.001). The family Trichostrongylidae was found in both age groups. The genera identified were Strongyloides sp. (47.2%), Cooperia sp. (33.9%), and Haemonchus sp. (10.4%), as well as Eimeria sp., Moniezia sp., Trichuris sp., and Strongyloides sp. The highest parasite burden corresponded to the genus Strongyloides sp. with 1108.9 EPG. There is a need to carry out further studies in order to know the prevalence and incidence of nematode affecting to B. bubalis as an introduced animal species to Mexican tropics.

An Evaluation of Quantitative PCR Assays (TaqMan® and SYBR Green) for the Detection of Babesia bigemina and Babesia bovis, and a Novel Fluorescent-ITS1-PCR Capillary Electrophoresis Method for Genotyping B. bovis Isolates

Babesia spp. are tick-transmitted haemoparasites causing tick fever in cattle. In Australia, economic losses to the cattle industry from tick fever are estimated at AUD$26 Million per annum. If animals recover from these infections, they become immune carriers. Here we describe a novel multiplex TaqMan qPCR targeting cytochrome b genes for the identification of Babesia spp. The assay shows high sensitivity, specificity and reproducibility, and allows quantification of parasite DNA from Babesia bovis and B. bigemina compared to standard PCR assays. A previously published cytochrome b SYBR Green qPCR was also tested in this study, showing slightly higher sensitivity than the Taqman qPCRs but requires melting curve analysis post-PCR to confirm specificity. The SYBR Green assays were further evaluated using both diagnostic submissions and vaccinated cattle (at 7, 9, 11 and 14 days post-inoculation) showed that B. bigemina can be detected more frequently than B. bovis. Due to fewer circulating parasites, B. bovis detection in carrier animals requires higher DNA input. Preliminary data for a novel fluorescent PCR genotyping based on the Internal Transcribed Spacer 1 region to detect vaccine and field alleles of B. bovis are described. This assay is capable of detecting vaccine and novel field isolate alleles in a single sample.