Open Access
Research Article
Issue
Parasite
Volume 24, 2017
Article Number 14
Number of page(s) 11
DOI https://doi.org/10.1051/parasite/2017015
Published online 12 May 2017

© M.G. Montes Cortés et al., published by EDP Sciences, 2017

Licence Creative Commons
This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Introduction

Equine piroplasmoses (EPs) are important and widespread tick-borne diseases in horses. This parasitic disease affects all equid species including horses, donkeys, mules and zebras. Two species of parasites, Babesia caballi (Nuttall and Strickland 1910) and Theileria equi (formerly Babesia equi, Laveran 1901), cause this infection. These protozoa parasitise erythrocytes and they can co-infect animals [18, 65, 83]. The disease is characterised by a variety of symptoms such as fever, anaemia, jaundice, haematuria and lymphadenopathy [32]. The initial acute phase can cause death, but the survivor animals become carriers and reservoirs of infection for vector ticks [28]. Therefore, large economic losses are generated due to the treatments, the decrease in performance of the animals or the negative impact on international trade [31, 56].

In Spain, EPs are enzootic diseases [13, 31] as they have been diagnosed in autochthonous horses for decades [21, 22, 4143] but there is insufficient epidemiological information about this disease and its vectors in Spain.

Several diagnostic methods are used to detect the infection, such as microscopic examination of stained blood smears, which is useful in the acute phase of infection onset, though serological techniques are better in order to identify chronic carriers. These techniques include the complement fixation test (CFT), the indirect fluorescent antibody test (IFAT), and the competitive enzyme-linked immunosorbent assay (cELISA), which utilises the EMA-1 protein and a specific monoclonal antibody (MAb) to detect T. equi, and the recombinant RAP-1 protein and an MAb reactive with a peptide epitope of a 60 KDa B. caballi antigen to diagnose the other parasite. The last two tests are recommended by the World Organisation for Animal Health (OIE) for the serodiagnosis of EP [73]. The diagnosis of these haemoprotozoan infections can be carried out using molecular assays such as conventional single PCR [13], multiplex PCR [7, 96], nested PCR [72, 78, 95] or real-time PCR [54]. Thus, the combination of two or more of these methods is currently recommended to diagnose the EP [102].

The main goal of this survey was to estimate the seroprevalence and geographic distribution of EP in central and southwest Spain. In fact, it is the largest study that has been conducted in Spain. It is intended to identify areas in which to implement more effective control measures against both the pathogens and their vectors. In addition, we analysed 108 randomly selected sera samples to compare concordance of the two serological methods most often used in the diagnosis of this parasitic infection that affects equids in Spain: the indirect fluorescence antibody test (IFAT) vs. an immunoenzymatic assay (cELISA). This study helped to further understand the situation of the Purebred Spanish Horse with regard to these infections in this emblematic and autochthonous breed.

Materials and methods

Sampled animals and area of study

This study was carried out between February and September 2014 in various regions of Spain: Andalusia, Castilla-La Mancha, Castilla-León, Extremadura and Madrid (Fig. 1). Blood samples were collected from horses’ jugular veins into sterile vacuum tubes with and without anticoagulant. Plasma and serum samples were obtained by centrifugation at 4° C at 2500 rpm for 10 min and were stored at −20° C until testing. The plasma and sera were used for the IFAT and the cELISA, respectively.

thumbnail Figure 1.

Map of equine piroplasmosis prevalence by region in Spain. The histogram within each province represents the positive horses using percentages.

This study included 3100 animals (1309 females and 1791 males) with no clinical signs of piroplasmoses between 9 months and 30 years of age (mean age: 7.5 years). Different breeds were tested including the Spanish Pure Breed horse, Anglo-Arabian, Arabian horse, Balearic horse, Hanoverian horse, Lusitano, Thoroughbred, Selle Français and crossbred horses. Information on aptitude was annotated; thus, most of the animals were breeding horses though there were saddle horses (recreation or sports). Data were studied according to recorded information sent by owners and/or veterinarians: gender, breed, age, geographical origin and coat colour.

Win Episcope 2.0 was used [99] to estimate the minimal sample size needed to guarantee the validity of this study. According to the equine census data obtained in 2013 from MAGRAMA (“Ministerio de Agricultura, Alimentación y Medio Ambiente”, Spain) [61] in each region studied (Table S1), at least 381 animals from each area were sufficient in order to detect a 50% prevalence of subclinical EP infection with a certainty of 95% [89]. However, in the region of Madrid, the sample size was smaller than necessary (n = 312) (Fig. 1, Table S1).

Indirect fluorescence antibody test (IFAT) and immunoenzymatic assay (cELISA)

The IFAT was used for the detection of antibodies against T. equi and B. caballi. The antigen was obtained from naturally infected horses with a parasitaemia higher than 3%. Both protocols to prepare the T. equi and the B. caballi antigen and the assay were conducted as described by Camacho et al. [21]. The slides were examined under the fluorescence microscope (Leica DMLS®) at a magnification of 400 (10 × 40). Positive and negative sera were included in each run as controls.

The cELISA test was carried out with commercially available test kits (VMRD, Inc. Pullman, WA, USA) to detect antibodies against T. equi and B. caballi. These tests were conducted following the manufacturer’s instructions. The plates were read on a plate reader (Multiskan Ascent, Thermo Electron Corporation®) at an optical density of 620 nm. Samples associated with percent inhibition (PI) values <40% were considered negative, while if the PI value was ≥40%, sera were considered positive.

The IFAT and the cELISA techniques are the most useful methods to diagnose equine piroplasmoses. For this reason, a comparison between the techniques was needed since it had not been done previously in Spain. Thus, from the 3100 serum samples tested by IFAT, 108 samples were randomly selected and tested by cELISA.

Statistical analysis

The seroprevalences of T. equi, B. caballi and co-infection relative to certain characteristics (age, breed, coat colour, gender and geographical location) were determined at the 95% confidence interval (CI). These epidemiological data were compared with the IFAT results using a logistic regression-binary (LR-binary). Animals were considered as units of analysis for determining the significance of association. Data analyses were performed using Statistical Package for Social Sciences (SPSS) 11.0 software for Windows. The odds ratios were calculated at a 95% confidence interval (95% CI). Tests with a p-value ≤ 0.05 were considered statistically significant.

Due to the semi-quantitative characteristic of age as a variable, it was evaluated by both (i) exploring the difference in means between categories in the IFAT variable, and (ii) using it as an ordinal variable, then using the OR calculated as the average value of each risk factor compared to the previous in descending order. The statistical significance of seroprevalence between pairs of regions (Castilla-La Mancha, Andalusia, Castilla-León, Extremadura and Madrid) was calculated using a non-parametric test with the Monte Carlo Method. In order to determine the concordance between the two serological techniques (the IFAT and the cELISA), Cohen’s κ test was used [24]. The κ values < 0 indicate no agreement and values between 0 and 0.20 indicate slight agreement, 0.21–0.4 fair agreement, 0.41–0.60 moderate, 0.61–0.80 substantial and 0.81–1 almost perfect agreement.

Results

Seroepidemiological study

The serological examination of 3100 horses by IFAT showed that the overall seroprevalence of the equine piroplasmoses in southwest Spain was 52.45% (SE = 0.009). Of the 3100 tested samples, 1381 sera (44.55%; SE = 0.009) were positive for T. equi, 643 samples (20.74%; SE = 0.007) were positive for B. caballi and 398 horses (12.84%; SE = 0.006) had antibodies against both parasites.

The seroprevalence in horses from Castilla-La Mancha was the highest (67.54%) (significance calculated by the Monte Carlo method [95% CI]; p < 0.001). The prevalence results in horses from Andalusia, Castilla-León and Extremadura (50.94%; 53.62% and 51.5%, respectively) were not statistically significant (significance calculated by the Monte Carlo method [95% CI] ns). The lowest seroprevalence was observed in Madrid (38.14%) (significance calculated by the Monte Carlo method [CI 95%]; p < 0.001) (Table 1). The mean age by region was as follows: 6.24 (SE = 0.183), 7.15 (SE = 0.250), 10.25 (SE = 0.320), 6.43 (SE = 0.161) and 8.26 (SE = 0.384) years for Andalusia, Castilla-La Mancha, Castilla-León, Extremadura and Madrid, respectively.

Table 1.

Prevalence of T. equi and B. caballi antibodies (by IFAT) in horses from different regions of Spain

In this study, it has been shown that T. equi, B. caballi and mixed infection were detected across regions. Notably, the parasite detected most frequently was T. equi, ranging from 62.57 to 32.37% in Andalusia and Madrid, respectively (Table 1). However, B. caballi prevalence was half as high, ranging from 31.16 to 12.20% in Castilla-León and Extremadura, respectively (Table 1). The maximum of mixed infections was 16.38% in Castilla-León (Table 1). The regional seroprevalence for male and female horses is shown in Table 1 (see also Table S2 for province details).

Approximately half of the tested Spanish Pure Breed horses were seropositive (50.89%) consisting of 41.69% horses T. equi seropositive and 16.32% seropositive for B. caballi. Meanwhile, 9.90% of the tested horses were positive for both parasites.

Regarding the goodness of the LR-binary model (χ2 = 372.93; p < 0.0001 and B = 0.098 (SE = 0.038); p < 0.006), age (p < 0.0001), breed (p < 0.004) and geographical location (p < 0.0001) were significant, explaining between 0.155 (Cox and Snell’s R2) and 0.207 (Nagelkerke’s R2) of the dependent variable (seroprevalence), with 62.4% of the cases correctly classified. This indicates that the model is acceptable. Other risk factors, the coat colour and the gender, were not significant and fall out of the model (Tables S3 and S4 for T. equi and B. caballi, respectively, for details). The difference between average age of the positive and the negative horses (6.92 [95% CI: 6.61–7.22] subtracted from 8.19 [95% CI: 7.86–8.53]) by the T. equi IFAT test was 1.27 years. On the basis of these results, non-overlap between the CIs of the average ages supported statistically significant differences in the age of seropositivity, based on the IFAT test. Moreover, the OR values between a specific age and the previous one were slightly similar but significantly increased from three to 11 years of age. This was accompanied by a change of significance regarding the percentages in seroprevalence, reaching a threshold of around 44–65% of positivity from eleven years of age. Regarding the breed, OR values are significantly different among non-native breeds such as Arabian horses, Thoroughbred, Selle Français and crossbreeds, which always showed OR values higher than those from the autochthonous breeds like Spanish Pure Breed horses for T. equi. Focusing on the geographical distribution, it was observed that there was a higher risk of T. equi infection in Extremadura and Castilla-León since the OR was significant.

A similar result was obtained for B. caballi, since neither coat colour nor gender was risk factor for this parasitic infection. The difference between the average age for seronegative and seropositive horses was 1.75 years (7.14 [95% CI: 6.90–7.39], that is the mean age of seronegative horses, subtracted from 8.89 [95% CI: 8.31–9.57], that is the mean age of seropositive through the IFAT test). This difference was slightly higher than that for T. equi. The infection risk increased until 12 years of age; from there, the seropositivity settled around 20–45% and there were no significant differences of seroprevalence above 12 years of age. However, the OR between a specific age group and the previous one for B. caballi was about three times higher than for T. equi, but turnover (more frequent negativity change to more frequent positivity) in favour of positivity from the nine-year threshold occurs only for T. equi (Table S3). There was a significant association between the breeds Arabian horses and Thoroughbred, and seropositivity for B. caballi. The seropositivity rate in Extremadura was significantly lower than in other regions.

IFAT vs. cELISA results

The concordance between the techniques was similar. Of the 108 tested sera samples, both diagnostic methods showed concordant results for T. equi in 91 sera (84.26%), meanwhile for B. caballi the same results were observed in 89 samples (82.41%). Focusing on the anti-T. equi antibodies, 7 sera were positive by IFAT but were found negative by the cELISA, and 10 serum samples were negative by IFAT but positive by cELISA. Analysing the B. caballi results, it was found that 16 horses had antibodies for that parasite by IFAT but did not show reactivity in the cELISA, and three animals were negative by IFAT but positive by cELISA (Table 2).

Table 2.

Serological results by IFAT and cELISA for T. equi (A) and B. caballi (B), respectively.

The concordance between the two serological methods for T. equi using the κ coefficient was 0.68. According to Landis and Koch’s rating scale for the κ index, there was substantial agreement between the techniques. A fair agreement (Cohen’s κ = 0.22) was observed between the techniques for B. caballi.

Discussion

Equine piroplasmoses are diseases that affect a large number of horses worldwide. Spain is an enzootic zone; therefore, information about the prevalence of this infection in horse populations is essential to control the disease and to reduce the economic losses generated. Different serological tests are available for epidemiological studies (IFAT, cELISA) [56, 58]. Currently, both techniques are recommended by the World Organisation for Animal Health for importation [73]. This study mainly used the IFAT and 108 randomly selected samples were analysed using both methods. Importantly, survey samples were collected from a large area in Spain, which made it possible to estimate the overall prevalence in a more realistic manner. Several studies on the seroprevalence of EPs in Spain have been published, although most of them were not as extensive as the present survey. These diseases are widespread in Spain and seroprevalence is high, as it has been reported by other authors [21, 22, 35, 41, 43].

Recently, a survey carried out in all of Spain showed a T. equi seroprevalence of 21.9%, a prevalence of 5% for B. caballi and co-infection in 2.71% of the tested animals using the cELISA [22]. In the Andalusia region, García-Bocanegra et al. [35] reported a slightly higher seroprevalence for T. equi (48.6% vs. 43.61% in the present survey), but the B. caballi prevalence was 7.9% in the former, while in the present study it was 22.22%. In 2005, Camacho et al. [21] in Galicia (northwest Spain) estimated the seropositivity for B. caballi to be 28.3% in healthy horses using IFAT, which was similar to our results. The difference could be explained by variations in abiotic factors and tick fauna distribution. Furthermore, the particular results for B. caballi may also be explained by the use of different diagnostic techniques. Thus, in the present study, it was revealed that the agreement between the cELISA and the IFAT was poorer for B. caballi. This difference could be due to the fact that IFAT slides were made with an autochthonous strain, while the commercial cELISA kit used a RAP-1 foreign antigen, leading to differences in the specificity and the sensitivity of the techniques. As we did, Camacho et al. [21] used the same IFAT technique, which led to a more accurate comparison among regions using the data from both studies. The prevalence estimated in other countries with IFAT or cELISA was different from the present survey. The EP prevalence was higher than in Spain in countries such as Colombia (≥90%) [98], Brazil 78.8% and 65.7% for T. equi and B. caballi, respectively, [44] or 97.5% for EP [100] and Mongolia with 82.3% EP seroprevalence [16], or 78.8% for T. equi and 65.7% for B. caballi, respectively [84]. However, it was lower in countries such as the UAE (33.3%) [48], Sudan (25.2%) [85], Portugal (17.9% and 11.1% for T. equi and B. caballi, respectively) [80], Turkey (18.4–18.5%) [51, 90], Jordan (14.6%) [2], Greece (11.6%) [56], Saudi Arabia (10.4% and 7.5% for T. equi and B. caballi, respectively) [6], Italy (8.5%) [40], Switzerland (7.3%) [92], the Netherlands (4%) [19] and Korea (1.1%) [87]. In other studies, the T. equi seroprevalence was higher than that described in Spain, but the seropositivity for B. caballi was lower, this is the case for France (from 58% to 80% for T. equi and from 1.2% to 12.9% for B. caballi) [33, 38] and Iran (48% and 2%) [1]. Meanwhile, a lower prevalence of T. equi was described in Hungary (32%) [30], northern Italy (12.4%) [67] and the Azores Islands (9.1%) [11]. The EP seroprevalence discrepancies could be related to housing conditions, grazing and activity of horses [38, 56, 100]. Also, the measures for control of these diseases, the selected test for the diagnosis [2, 35, 56, 67], the climate and the tick fauna could be important. Thus, temperature and/or humidity and/or precipitation could increase or decrease tick populations [56, 9496].

Using the IFAT, the T. equi seroprevalence was higher than that of B. caballi. Different trends were observed by other authors using different techniques (Table 3). T. equi was the predominant parasite in 82.14% of the studies in respect to B. caballi, but after excluding two studies [60, 81] due to discrepancies between diagnostic methods regarding the predominant haemoparasite.

Table 3.

T. equi and B. caballi prevalence by different diagnostic methods, including geographical distribution and predominant parasite.

Infected horses may remain lifelong carriers of T. equi, whereas B. caballi is eliminated from the bloodstream 1–4 years post-infection, which could explain the seroprevalence difference for these parasites [12, 28, 85]. This fact could explain why in horses older than nine years, the percentage of infected animals exceeds that of uninfected animals in the case of T. equi, which never occurs for B. caballi. Furthermore, treatments do not completely eliminate T. equi from the animals [18, 28]. The situation reported by other authors is different since B. caballi is more prevalent than T. equi, which has been related to the presence of the appropriate tick vectors for the transmission of B. caballi [69].

Several authors [4, 12, 35, 38, 45, 49, 50, 56, 70, 74, 77, 79, 84, 90, 100] suggested that age was a risk factor, since older animals could have been exposed to ticks for a longer period than young animals. Nevertheless, other authors showed the absence of an age-prevalence relationship [1, 3, 8, 10, 17, 23, 26, 36, 40, 46, 69, 75, 76, 80, 92, 94]. The present study pointed out that less than 1/4 of the foals and yearlings were seropositive for both parasites, with an increase in the percentage of infected horses until stabilisation at 11 and 14 years of age for T. equi and B. caballi, respectively, as Cantú-Martínez et al. reported [23]. Other studies have also reported that T. equi antibodies were higher in older than in young animals [8, 9, 27, 50, 51, 56]. In addition, Vieira et al. [100] indicate that the seroprevalence of T. equi increased with age but in contrast, the presence of antibodies to B. caballi decreased in the oldest animals, which resembles the pattern described in this study. There is evidence that animals infected with T. equi may become lifelong carriers [18]. However, infection with B. caballi may also persist in the subclinical state for 1–4 years only. This fact may partially explain our results, whereby T. equi seroprevalence remained over 60% from eleven years of age, but B. caballi seroprevalence did not exceed the level of 44% in 16-year-old horses in Spain, where these parasites cohabit.

It was found that Spanish breeds have a lower infection prevalence than non-native breeds. Sevinc et al. [90] and Aharonson-Raz et al. [4] recognised that the seroprevalence in Arabian horses was higher, as also found in the present study, especially for B. caballi. Bartolomé del Pino et al. [12] indicated that the prevalence in crossbred horses was significantly higher than other (pure) breeds. Other surveys showed no association between infection prevalence and breed [2, 10, 36, 75].

Shkap et al. [91] considered that the differences in prevalence between male and female horses may be due to different management practices for the two sexes. In the present study, however, differences between male and female horses were not observed.

In contrast to Aharonson-Raz et al. [4], no significant association between coat colour and the results of the diagnostic test was observed. Further studies are needed to understand the origin of this difference.

Significantly higher seroprevalence was obtained only in Extremadura and Castilla-León horses. There have also been studies that demonstrated statistically significant differences between counties or regions [2, 3, 8, 12, 16, 26, 29, 35, 51, 52, 56, 87, 91, 94, 96].

With respect to Cohen’s κ analysis, the concordance between the IFAT and the cELISA for T. equi was higher than for B. caballi, showing a fair agreement for B. caballi. The EMA-1 gene of the strains used to make the T. equi recombinant antigen in the cELISA and the strains from Spain were probably similar. Consequently, for B. caballi, the different results between this technique and cELISA may be related to this fact. However, the RAP-1 gene of strains used to make the recombinant antigen in the cELISA could be different from the RAP-1 gene of Spanish strains. Recently, Montes et al. [66] showed one Spanish B. caballi strain to be genetically different from that described by Cacciò et al. [20] based on the β-tubulin gene. Also, the existence of genetic differences between strains within a country or among countries has been reported previously [14, 25, 71]. These authors showed that there was heterogeneity in the 18S rRNA gene both for T. equi and B. caballi in Spain and South Africa. In support of our study and focusing on the RAP-1 gene of B. caballi, Bhoora et al. [15], Rapoport et al. [79] and Mahmoud et al. [62] indicated failure to detect the B. caballi parasite. In accordance with Rapoport et al. [79], there could be doubts as to the ability of the cELISA to serve as a sole regulatory test for the international horse trade. The IFAT used in the present survey was performed with Spanish B. caballi strains, since it appears that they detect the presence of haemoparasite antibodies more successfully than the cELISA. Thus, Kuttler et al. [59] and Prochno et al. [76] confirmed that, due to regional differences, the use of antigens from autochthonous strains provides the best results.

Conclusions

The risk factors that seem to be associated with the presence of equine piroplasmoses in Spain are age, breed and geographical location. Meanwhile, coat colour and gender were not significantly associated in these diseases. The seroprevalence in young animals is relatively low, but as horses get older they become seropositive, especially concerning T. equi. In addition, the comparison between IFAT and cELISA revealed a possible underestimation of the presence of B. caballi when using cELISA.

Conflict of interest

The authors declare there is no conflict of interest

Acknowledgments

The authors would like to thank the field veterinarians and the owners of the horses. They also thank Dr. Jacinto Garrido Velarde for his help with map design. Also we thank the "Junta de Extremadura, Consejería de Economía e Infraestructuras – Ayuda GR15085-; and Fondo Europeo de Desarrollo Regional (FEDER)/European Regional Development Fund (ERDF)”.

References

  1. Abedi V, Razmi G, Seifi H, Naghibi A. 2014. Molecular and serological detection of Theileria equi and Babesia caballi infection in horses and ixodid ticks in Iran. Ticks and Tick-borne Diseases, 5(3), 239–244. [CrossRef] [PubMed] (In the text)
  2. Abutarbush SM, Alqawasmeh DM, Mukbel RM, Al-Majali AM. 2012. Equine babesiosis: Seroprevalence, risk factors and comparison of different diagnostic methods in Jordan. Transboundary and Emerging Diseases, 59(1), 72–78. [CrossRef] [PubMed] (In the text)
  3. Acici M, Umur S, Givenc T, Arslan HH, Kurt M. 2008. Seroprevalence of equine babesiosis in the Black Sea region of Turkey. Parasitology International, 57(2), 198–200. [CrossRef] [PubMed] (In the text)
  4. Aharonson-Raz K, Rapoport A, Hawari IM, Lensky IM, Berlin D, Zivotofsky D, Klement E, Steinman A. 2014. Novel description of force of infection and risk factors associated with Theileria equi in horses in Israel and in The Palestinian Authority. Ticks and Tick-borne Diseases, 5(4), 366–372. [CrossRef] [PubMed] (In the text)
  5. Akkan HA, Karaca M, Tutuncu M, Deger S, Keles I, Agaoglu Z. 2003. Serologic and microscopic studies on babesiosis in horses in the eastern border of Turkey. Journal of Equine Veterinary Sciences, 5(23), 181–183. [CrossRef] (In the text)
  6. Alanazi AD, Alyousif MS, Hassieb MM. 2012. Seroprevalence study on Theileria equi and Babesia caballi antibodies in horses from central province of Saudi Arabia. Journal of Parasitology, 98(5), 1015–1017. [CrossRef] (In the text)
  7. Alhassan A, Pumidonming W, Okamura M, Hirata H, Battsetseg B, Fujisaki K, Yokoyama N, Igarashi I. 2005. Development of a single-round and multiplex PCR method for the simultaneous detection of Babesia caballi and Babesia equi in horse blood. Veterinary Parasitology, 129(1–2), 43–49. [CrossRef] [PubMed] (In the text)
  8. Asgarali Z, Coombs DK, Mohammed F, Campbell MD, Caesar E. 2007. A serological study of Babesia caballi and Theileria equi in thoroughbreds in Trinidad. Veterinary Parasitology, 144(1–2), 167–171. [CrossRef] [PubMed] (In the text)
  9. Ayala-Valdovinos MA, Lemus-Flores C, Galindo-García J, Bañuelos-Pineda J, Rodríguez-Carpena JG, Sánchez-Chiprés D, Duifhuis-Rivera T. 2017. Diagnosis and prevalence of Theileria equi in western Mexico by nested PCR. Parasitology International, 66, 821–824. [CrossRef] [PubMed] (In the text)
  10. Bahrami S, Ghadrdan AR, Mirabdollahi SM, Fayed MR. 2014. Diagnosis of subclinical equine theileriosis in center of Iran using parasitological and molecular methods. Tropical Biomedicine, 31(1), 110–117. [PubMed] (In the text)
  11. Baptista C, Lopes MS, Tavares AC, Rojer H, Kappmeyer L, Mendoça D, da Câmara Machado A. 2013. Diagnosis of Theileria equi infections in horses in the Azores using cELISA and nested PCR. Ticks and Tick-borne Diseases, 4(3), 242–245. [CrossRef] [PubMed] (In the text)
  12. Bartolomé del Pino LE, Nardini R, Veneziano V, Iacoponi F, Cersini A, Autorino GL, Buono F, Sicluna MT. 2016. Babesia caballi and Theileria equi infections in horses in Central-Southern Italy: Sero-molecular Surrey and associated risk factors. Ticks and Tick-borne Diseases, 7, 462–469. [CrossRef] [PubMed] (In the text)
  13. Bashiruddin JB, Cammà C, Rebelo E. 1999. Molecular detection of Babesia equi and Babesia caballi in horse blood by PCR amplification of part of the 16S rRNA gene. Veterinary Parasitology, 84, 75–83. [CrossRef] [PubMed] (In the text)
  14. Bhoora R, Franssen L, Oosthuizen MC, Guthrie AJ, Zweygarth E, Penzhorn BL, Jongejan F, Collins NE. 2009. Sequence Heterogeneity in the 18S rRNA gene within Theileria equi and Babesia caballi from horses in South Africa. Veterinary Parasitology, 159, 112–120. [CrossRef] [PubMed] (In the text)
  15. Bhoora R, Quan M, Zweygarth E, Guthrie AJ, Prinsloo SA, Collins NE. 2010. Sequence heterogeneity in the gene encoding the rhoptry-associated protein-1 (RAP-1) of Babesia caballi isolates from South Africa. Veterinary Parasitology, 169(3–4), 279–288. [CrossRef] [PubMed] (In the text)
  16. Boldbaatar D, Xuan X, Battsetseg B, Igarashi I, Battur B, Batsukh Z, Bayambaa B, Fujisaki K. 2005. Epidemiological study of equine piroplasmosis in Mongolia. Veterinary Parasitology, 127(1), 29–32. [CrossRef] [PubMed] (In the text)
  17. Botteon PTL, Massard CL, Botteon RCCM, Loss ZG, Linhares GFC. 2002. Seroprevalence of Babesia equi in three breeding systems of equines. Rio de Janeiro-Brazil. Parasitología Latinoamericana, 57(3–4), 141–145. (In the text)
  18. Brüning A. 1996. Equine piroplasmosis: an update on diagnosis, treatment and prevention. British Veterinary Journal, 152(2), 139–151. [CrossRef] (In the text)
  19. Butler CM, Sloet van Oldruitenborgh-Oosterbaan MM, Stout TAE, van der Kolk JH, Lv Wollenberg, Nielen M, Jongejan F, Werners AH, Houwers DJ. 2012. Prevalence of the causative agents of equine piroplasmosis in the South West of The Netherlands and the identification of two autochthonous clinical Theileria equi infections. The Veterinary Journal, 193(2), 381–385. [CrossRef] (In the text)
  20. Cacciò S, Cammà C, Onuma M, Severini C. 2000. The beta-tubulin gene of Babesia and Theileria parasites is an informative marker for species discrimination. International Journal for Parasitology, 30, 1181–1185. [CrossRef] [PubMed] (In the text)
  21. Camacho AT, Guitian FJ, Pallas E, Gestal JJ, Olmeda AS, Habela MA, Telford SR III, Spielman A. 2005. Theileria (Babesia) equi and Babesia caballi infections in horses in Galicia, Spain. Tropical Animal Health and Production, 37(4), 293–302. [CrossRef] [PubMed] (In the text)
  22. Camino E, Carvajal KA, Lozano FJ, Viñolo C, Alende T, Domínguez L, Cruz F. 2016. Estudio de seroprevalencia de piroplamosis equina en España en muestras previas a la exportación. XXI Simposio Anual Avedila, Murcia. (In the text)
  23. Cantú-Martínez MA, Segura-Correa JC, Silva-Páez ML, Avalos-Ramírez R, Wagner GG. 2012. Prevalence of antibodies to Theileria equi and Babesia caballi in horses from Northeastern Mexico. Journal of Parasitology, 98(4), 869–870. [CrossRef] (In the text)
  24. Cohen J. 1960. A coefficient of agreement for nominal scales. Educational and Psychological Measurement, 20, 37–46. [CrossRef] (In the text)
  25. Criado-Fornelio A, González-del-Río MA, Buling-Saraña A, Barba-Carretero JC. 2004. The “expanding universe” of piroplasms. Veterinary Parasitology, 119(4), 337–345. [CrossRef] [PubMed] (In the text)
  26. Davitkov D, Vucicevic M, Stevanovic J, Krstic V, Slijepcevic D, Glavinic U, Stanimirovic Z. 2016. Molecular detection and prevalence of Theileria equi and Babesia caballi in horses of central Balkan. Acta Parasitologica, 61(2), 337–342. [CrossRef] [PubMed] (In the text)
  27. De Campos CHC, Prado RFS, Guimãraes A, da Silva AT, Baldani CD, Cordeiro MD, Pires MS, Peixoto MP, dos Santos HA, Machado RZ, Fonseca AH, Massard CL. 2013. Aspectos epidemiológicos e soroprevalência de Theileria equi em equinos de uso military no munícipio de Resende, estado do Rio de Janeiro, Brasil. Revista Brasileira de Medicina Veterinária, 35(S2), 106–112. (In the text)
  28. De Waal DT, Van Heerden J. 1994. Equine Piroplasmosis, in Infectious Diseases of Livestock, Coetzer JAW, Tustin RC, Editors. Oxford University Press: New York. p. 295–304. (In the text)
  29. Dos Santos TM, Roier EC, dos Santos HA, Pires MS, Vilela JA, Moraes LM, Almeida FQ, Baldani CD, Machado RZ, Massard CL. 2011. Factors associated to Theileria equi in equids of two microregions from Rio de Janeiro. Brazil. Revista Brasileira de Parasitologia Veterinária, 20(3), 235–241. [CrossRef] (In the text)
  30. Farkas R, Tanczos B, Gyurkovszky M, Fölsvári G, Solymosi N, Edelhofer R, Hornok S. 2013. Serological and molecular detection of Theileria equi infection in horses in Hungary. Veterinary Parasitology, 192, 143–148. [CrossRef] [PubMed] (In the text)
  31. Friedhoff KT, Tenter AM, Müller I. 1990. Haemoparasites of equines: impact on international trade of horses. Revue Scientifique et Technique Office International des Épizooties, 9(4), 1187–1194. (In the text)
  32. Friedhoff KT, Soulé C. 1996. An account on equine babesiosis. Revue Scientifique et Technique Office International des Épizooties, 15, 1191–1201. [CrossRef] (In the text)
  33. Fritz D. 2010. A PCR study of piroplasms in 166 dogs and 111 horses in France (March 2006 to March 2008). Parasitology Research, 106(6), 1339–1342. [CrossRef] [PubMed] (In the text)
  34. Gallusová M, Qablan MA, D’Amico G, Oborník M, Petrželková KJ, Mihalca AD, Modrý D. 2014. Piroplasms in feral and domestic equines in rural areas of the Danube Delta, Romania, with survey of dogs as a possible reservoir. Veterinary Parasitology, 206(3–4), 287–292. [CrossRef] [PubMed] (In the text)
  35. García-Bocanegra I, Arenas-Montes A, Hernández E, Adaszek L, Carbonero A, Almería S, Jaén-Téllez JA, Gutiérrez-Palomino P, Arenas A. 2013. Seroprevalence and risk factors associated with Babesia caballi and Theileria equi infection in equids. Veterinary Journal, 195(2), 172–178. [CrossRef] (In the text)
  36. Golynski AA, Fernandes KR, Baldani CD, Golynski AL, Madeiro AS, Machado RZ, Botteon P de T, Massard CL. 2008. Seroepidemiological studies on Babesia equi in horses from the State of Rio Grande do Sul determined by indirect immunofluorescence test and Elisa. Revista Brasileira de Parasitologia Veterinária, 17(S1), 317–321. (In the text)
  37. Güçlü HZ, Karaer KZ. 2007. Detection of Babesia caballi (Nuttall, 1910) and Theileria equi (Syn. Babesia equi, Laveran, 1901) by the polymerase chain reaction (PCR) in show and sport horses in the region of Ankara. Turkiye Parazitologi Dergisi, 31(2), 89–93. (In the text)
  38. Guidi E, Pradier S, Lebert I, Leblond A. 2015. Piroplasmosis in an endemic area: analysis of the risk factors and their implications in the control of theileriosis and babesiosis in horses. Parasitology Research, 114(1), 71–83. [CrossRef] [PubMed] (In the text)
  39. Guven E, Avcioglu H, Deniz A, Balkaya İ, Abay U, Yavuz Ş, Akyüz M. 2017. Prevalence and molecular characterization of Theileria equi and Babesia caballi in jereed horses in Erzurum, Turkey. Acta Parasitologica, 62(1), 207–213. [CrossRef] [PubMed] (In the text)
  40. Grandi G, Molinari G, Tittarelli M, Sassera D, Kramer LH. 2011. Prevalence of Theileria equi and Babesia caballi infection in horses from Northern Italy. Vector-Borne and Zoonotic Diseases, 11(7), 955–956. [CrossRef] (In the text)
  41. Habela M, Reina D, Nieto D, Verdugo SG, Navarrete I. 1989. Epidemiología de la babesiosis equina en Extremadura: estudio preliminar. Medicina Veterinaria, 6, 31–39. (In the text)
  42. Habela M, Grande A, Antón JM, Mora JA, Moreno F, Pérez-Martín JE. 1995. Aportaciones al conocimiento de la distribución y clínica de la babesiosis equina en España. IV Congreso Ibérico de Parasitología, Santiago de Compostela.
  43. Habela MA, Gragera-Slikker A, Moreno A, Montes G, Sevilla R. 2005. Piroplasmosis equina: conocimiento y grado de concienciación de los productores de caballos Pura Raza Española. Revista Equinus, 11, 17–34. (In the text)
  44. Heim A, Passos LM, Ribeiro MF, Costa-Júnior LM, Bastos CV, Cabral DD, Hirzmann J, Pfister K. 2007. Detection and molecular characterizaion of Babesia caballi and Theileria equi isolates from endemic areas of Brazil. Parasitology Research, 102(1), 63–68. [CrossRef] [PubMed] (In the text)
  45. Heuchert CM, de Giulli V, de Athaide DF, Böse R, Friedhoff KT. 1999. Seroepidemiologic studies on Babesia caballi infections in Brazil. Veterinary Parasitology, 85, 1–11. [CrossRef] [PubMed] (In the text)
  46. Hussain MH, Saqib M, Raza F, Muhammad G, Asi MN, Mansoor MK, Saleem M, Jabbar A. 2014. Seroprevalence of Babesia caballi and Theileria equi in five draught equine populated metropolises of Punjab, Pakistan. Veterinary Parasitology, 202(3–4), 248–256. [CrossRef] [PubMed] (In the text)
  47. Ikadai H, Nagai A, Xuan X, Igarashi I, Kamio T, Tsuji N, Oyamada T, Suzuki N, Fujisaki K. 2002. Seroepidemiologic studies on Babesia caballi and Babesia equi infections in Japan. Journal of Veterinary Medicine Science, 64(4), 325–328. [CrossRef] (In the text)
  48. Jaffer O, Abdishakur F, Hakimuddin F, Riya A, Wernery U, Schuster RK. 2010. A comparative study of serological tests and PCR for the diagnosis of equine piroplasmosis. Parasitology Research, 106(3), 709–713. [CrossRef] [PubMed] (In the text)
  49. Javed K, Ijaz M, Ali MM, Khan I, Mehmood K, Ali S. 2014. Prevalence and hematology of tick borne hemoparasitic diseases in Equines in and around Lahore, Pakistan. Journal of Zoology, 46(2), 401–408. (In the text)
  50. Kamyingkird K, Yangtara S, Desquesnes M, Cao S, Adjou PK, Jittapalapong S, Nimsupan B, Terkawi MA, Masatani T, Nishikawa Y, Igarashi I, Xuan X. 2014. Seroprevalence of Babesia caballi and Theileria equi in horses and mules from Northern Thailand. Journal of Protozoology Research, 24, 11–17. (In the text)
  51. Karatepe B, Karatepe M, Cakmak A, Karaer Z, Ergün G. 2009. Investigation of seroprevalence of Theileria equi and Babesia caballi in horses in Nidge province, Turkey. Tropical Animal Health and Production, 41(1), 109–113. [CrossRef] [PubMed] (In the text)
  52. Kerber CE, Ferreira F, Pereira MC. 1999. Control of equine piroplasmosis in Brazil. Onderstepoort Journal of Veterinary Research, 66, 123–127. (In the text)
  53. Kerber CE, Labruna MB, Ferreira F, De Waal DT, Knowles DP, Gennari SM. 2009. Prevalence of equine Piroplasmosis and its association with tick infestation in the State of São Paulo, Brazil. Revista Brasileira de Parasitologia Veterinária, 18(4), 1–8. [CrossRef] (In the text)
  54. Kim C, Conza LB, Alhassan A, Iseki H, Yokoyama N, Xuan X, Igarashi I. 2008. Diagnostic real-time PCR assay for the quantitative detection of Theileria equi from equine blood samples. Veterinary Parasitology, 151, 158–163. [CrossRef] [PubMed] (In the text)
  55. Kizilarslan F, Yildirim A, Duzlu O, Inci A, Onder Z, Ciloglu A. 2015. Molecular detection and characterization of Theileria equi and Babesia caballi in horses (Equus ferus caballus) in Turkey. Journal of Equine Veterinary Science, 35, 830–835. [CrossRef] (In the text)
  56. Kouam MK, Kantzoura V, Gajadhar AA, Theis JH, Papadopoulos E, Theodoropoulos G. 2010. Seroprevalence of equine piroplasms and host-related factors associated with infection in Greece. Veterinary Parasitology, 169(3–4), 273–278. [CrossRef] [PubMed] (In the text)
  57. Kurt C, Yaman M. 2012. The investigation of the prevalence of Babesia equi and Babesia caballi in horses by microscopic and serologic (cELISA) methods in Adana Province. Yüzüncü yil Úniversitesi Veterinary Fakültesi Dergisi, 23(1), 1–4. (In the text)
  58. Kuttler KL. 1988. World-Wide impact of babesiosis, in Babesiosis of domestic animals and man. Ristic M, Editor. CRC Press: Boca Ratón, Florida. p. 1–22. (In the text)
  59. Kuttler KL, Goff WL, Gipson CA, Blackburn BO. 1988. Serologic response of Babesia equi infected horses as measured by complement-fixation and indirect fluorescent antibody tests. Veterinary Parasitology, 26(3–4), 199–205. [CrossRef] [PubMed] (In the text)
  60. Laus F, Veronesi F, Passamonti F, Paggi E, Cerquetella M, Hyatt D, Tesei B, Fioretti DP. 2013. Prevalence of tick borne pathogens in horses from Italy. Journal of Veterinary Medicine Science, 75(6), 715–720. [CrossRef] (In the text)
  61. MAGRAMA. 2013. http://www.mapama.gob.es/es/ganaderia/temas/produccion-y-mercados-ganaderos/indicadoreseconomicossectorequino2015_tcm7-386080.pdf (accessed 27 February 2017). (In the text)
  62. Mahmoud MS, El-Ezz NT, Abdel-Shafy S, Nassar SA, El Namaky AH, Khalil WK, Knowles D, Kappmeyer L, Silva MG, Suarez CE. 2016. Assessment of Theileria equi and Babesia caballi infections in equine populations in Egypt by molecular, serological and haematological approaches. Parasites and Vectors, 9(1), 260. [CrossRef] (In the text)
  63. Malekifard F, Tavassoli M, Yakhchali M, Darvishzadeh R. 2014. Detection of Theileria equi and Babesia caballi using microscopic and molecular methods in horses in suburb of Urmia, Iran. Veterinary Research Forum, 5(2), 129–133. (In the text)
  64. Mans BJ, Pienaar R, Latif AA. 2015. A review of Theileria diagnostics and epidemiology. International Journal for Parasitology, 4, 104–118. [PubMed] (In the text)
  65. Mehlhorn H, Schein E. 1998. Redescription of Babesia equi (Laveran, 1901) as Theileria equi (Mehlhorn, Schein 1998). Parasitology Research, 84, 467–475. [CrossRef] [PubMed] (In the text)
  66. Montes MG, Fernández-García JL, Habela MA. in press. Genetic variation of the beta-tubulin gene of Babesia caballi strains. Journal of Arthropod-Borne Diseases. (In the text)
  67. Moretti A, Mangili V, Salvatori R, Maresca C, Scoccia E, Torina A, Moretta I, Gabrielli S, Tampieri MP, Pietrobelli M. 2010. Prevalence and diagnosis of Babesia and Theileria infections in horses in Italy: a preliminary study. Veterinary Journal, 184(3), 346–350. [CrossRef] (In the text)
  68. Motloang MY, Thekisoe OMM, Alhassan A, Bakheit M, Motheo MP, Masangane FES, Thibedi ML, Inoue N, Igarashi I, Sugimoto C, Mbati PA. 2008. Prevalence of Theileria equi and Babesia caballi infections in horses belonging to resource-poor farmers in the north-eastern Free State Province, South Africa. Onderstepoort Journal of Veterinary Research, 75, 141–146. [CrossRef] (In the text)
  69. Mujica FF, Perrone T, Forlano M, Coronado A, Meléndez RD, Barrios N, Álvarez R, Granda F. 2011. Serological prevalence of Babesia caballi and Theileria equi in horses of Lara State, Venezuela. Veterinary Parasitology, 178(1–2), 180–183. [CrossRef] [PubMed] (In the text)
  70. Munkhjargal T, Sivakumar T, Battsetseg B, Nyamjargal T, Aboulaila M, Purevtseren B, Bayarsaikhan D, Byambaa B, Terkawi MA, Yokoyama N, Igarashi I. 2013. Prevalence and genetic diversity of equine piroplasms in Tov province, Mongolia. Infection, Genetics and Evolution, 16, 178–185. [CrossRef] (In the text)
  71. Nagore D, García-Sanmartín J, García-Pérez AL, Juste RA, Hurtado A. 2004. Detection and identification of equine Theileria and Babesia species by reverse line blotting: epidemiological Survey and phylogenetic analysis. Veterinary Parasitology, 123(1–2), 41–54. [CrossRef] [PubMed] (In the text)
  72. Nicolaiewsky TB, Richter MF, Lunge VR, Cuhna CW, Delagostin O, Ikuta N, Fonseca AS, Silva SS, Ozaki LS. 2001. Detection of Babesia equi (Laveran, 1901) by nested polymerase chain reaction. Veterinary Parasitology, 101, 9–21. [CrossRef] [PubMed] (In the text)
  73. OIE. 2017. Equine piroplasmosis, in Manual of diagnostic test and vaccines for terrestrial animals, http://www.oie.int/fileadmin/Home/eng/Health_standards/tahc/current/chapitre_equine_piroplasmosis.pdf (accessed 20 February 2017) (Chapter 12.7). (In the text)
  74. Olivera M, García F. 2001. Equine babesiosis seroprevalence in thoroughbred racing horse farms from Aragua and Carabobo State, Venezuela. Revista de la Facultad de Ciencias Veterinarias de la Universidad Central de Venezuela, 42(1–2), 3–13. (In the text)
  75. Posada-Guzmán MF, Dolz G, Romero-Zúñiga JJ, Jiménez-Rocha AE. 2015. Detection of Babesia caballi and Theileria equi in blood from equines from four indigenous communities in Costa Rica. Veterinary Medicine International, 2015, 236278. [PubMed] (In the text)
  76. Prochno HC, Scorsin LM, De Melo FR, Baldani CD, Falbo MK, de Aquino LC, Lemos KR. 2014. Seroprevalence rates of antibodies against Theileria equi in team roping horses from central-western region of Paraná. Revista Brasileira de Parasitologia Veterinária, 23(1), 85–89. [CrossRef] (In the text)
  77. Qablan MA, Obroník M, Petrželková KJ, Sloboda M, Shudiefat MF, Hořín P, Lukeš J, Modrý D. 2013. Infections by Babesia caballi and Theileria equi in Jordanian equids: epidemiology and genetic diversity. Parasitology, 140(9), 1096–1103. [CrossRef] [PubMed] (In the text)
  78. Rampersad J, Cesar E, Campbell MD, Samlal M, Ammons D. 2003. A field evaluation of PCR for the routine detection of Babesia equi in horses. Veterinary Parasitology, 114, 81–87. [CrossRef] [PubMed] (In the text)
  79. Rapoport A, Aharonson-Raz K, Berlin D, Tal S, Gottlieb Y, Klement E, Steinman A. 2014. Molecular characterization of the Babesia caballi rap-1 gene and epidemiological survey in horses in Israel. Infection, Genetics and Evolution, 23, 115–120. [CrossRef] (In the text)
  80. Ribeiro AJ, Cardoso L, Maia JM, Coutinho T, Cotovio M. 2013. Prevalence of Theileria equi, Babesia caballi and Anaplasma phagocytophilum in horses from the north of Portugal. Parasitology Research, 112(7), 2611–2617. [CrossRef] [PubMed] (In the text)
  81. Rosales R, Rangel-Rivas A, Escalona A, Jordan LS, Gonzatti MI, Asom PM, Perrone T, Silva-Iturriza A, Mijares A. 2013. Detection of Theileria equi and Babesia caballi infections in Venezuelan horses using competitive-inhibition ELISA and PCR. Veterinary Parasitology, 196(1–2), 37–43. [CrossRef] [PubMed] (In the text)
  82. Ros-García A, M’ghirbi Y, Hurtado A, Bouattour A. 2013. Prevalence and genetic diversity of piroplasms species in horses and ticks from Tunisia. Infection, Genetics and Evolution, 17, 33–37. [CrossRef] (In the text)
  83. Rothschild CM, Knowles DP. 2007. Equine Piroplasmosis, in Equine Infectious Diseases. Sello DC, Long MT, Editors. Saunders Elsevier: St. Louis, MO. p. 465–473. [CrossRef] (In the text)
  84. Rüegg SR, Torgerson P, Deplazes P, Mathis A. 2007. Age-dependent dynamics of Theileria equi and Babesia caballi infections in Southwest Mongolia based on IFAT and/or PCR prevalence data from domestic horses and ticks. Parasitology, 134(Pt 7), 939–947. [CrossRef] [PubMed] (In the text)
  85. Salim BOM, Hassan SM, Bakheit MA, Alhassan A, Igarashi I, Karanis P, AbdeIrahman MB. 2008. Diagnosis of Babesia caballi and Theileria equi infections in horses in Sudan using ELISA and PCR. Parasitology Research, 103(5), 1145–1150. [CrossRef] [PubMed] (In the text)
  86. Salim B, Bakheit MA, Kamau J, Sugimoto C. 2013. Current status of equine piroplasms in the Sudan. Infection, Genetics and Evolution, 16, 191–199. [CrossRef] (In the text)
  87. Seo MG, Yun SH, Choi SK, Cho GJ, Park YS, Kwon OD, Cho KH, Kim TH, Jeong KS, Park SJ, Kwon YS, Kwak D. 2011. Seroprevalence of equine piroplasms in the Republic of Korea. Veterinary Parasitology, 179(1–3), 224–226. [CrossRef] [PubMed] (In the text)
  88. Seo MG, Yun SH, Choi SK, Cho GJ, Park YS, Cho KH, Kwon OD, Kwak D. 2013. Molecular and phylogenetic analysis of equine piroplasms in the Republic of Korea. Research in Veterinary Science, 94, 579–583. [CrossRef] [PubMed] (In the text)
  89. Sgorbini M, Bonelli F, Nardoni S, Rocchigiani G, Corazza M, Mancianti F. 2015. Seroprevalence and molecular analysis of Babesia caballi and Theileria equi from Central Italy during a 10-year period. Journal of Equine Veterinary Science, 35, 865–868. [CrossRef] (In the text)
  90. Sevinc F, Maden M, Kumas C, Sevinc M, Ekici OD. 2008. A comparative study on the prevalence of Theileria equi and Babesia caballi infections in horse sub-populations in Turkey. Veterinary Parasitology, 156(3–4), 173–177. [CrossRef] [PubMed] (In the text)
  91. Shkap V, Cohen I, Leibovitz B, Savitsky Pipano E, Avni G, Shofer S, Giger U, Kappmeyer L, Knowles D. 1998. Seroprevalence of Babesia equi among horses in Israel using competitive inhibition ELISA and IFA assays. Veterinary Parasitology, 76(4), 251–259. [CrossRef] [PubMed] (In the text)
  92. Sigg L, Gerber V, Gottstein B, Doherr MG, Frey CF. 2010. Seroprevalence of Babesia caballi and Theileria equi in the Swiss horse population. Parasitology International, 59(3), 313–317. [CrossRef] [PubMed] (In the text)
  93. Sloboda M, Jirků M, Lukešová D, Qablan M, Batsukh Z, Fiala I, Hořín P, Modrý M, Lukeš J. 2011. A survey for piroplasmids in horses and Bactrian camels in North-Eastern Mongolia. Veterinary Parasitology, 179(1–3), 246–249. [CrossRef] [PubMed] (In the text)
  94. Steinman A, Zimmerman T, Klement E, Lensky IM, Berlin D, Gottlieb Y, Baneth G. 2012. Demographic and environmental risk factors for infection by Theileria equi in 590 horses in Israel. Veterinary Parasitology, 187(3–4), 558–562. [CrossRef] [PubMed] (In the text)
  95. Sumbria D, Singla LD, Kumar S, Sharma A, Dahiya RK, Setia R. 2016a. Spatial distribution, risk factors and haemato-biochemical alterations associated with Theileria equi infected equids of Punjab (India) diagnosed by indirect ELISA and nested PCR. Acta Tropica, 155, 104–112. [CrossRef] (In the text)
  96. Sumbria D, Singla LD, Sharma A. 2016. Theileria equi and Babesia caballi infection in equids in Punjab, India: a serological and molecular survey. Tropical Animal Health and Production, 48(1), 45–52. [CrossRef] [PubMed] (In the text)
  97. Teglas M, Matern E, Lein S, Foley P, Mahan SM, Foley J. 2005. Ticks and tick-borne disease in Guatemalan cattle and horses. Veterinary Parasitology, 131(1–2), 119–127. [CrossRef] [PubMed] (In the text)
  98. Tenter AM, Otte MJ, Gonzalez CA, Abuabara Y. 1988. Prevalence of piroplasmosis in equines in the Colombian province of Cordoba. Tropical Animal Health and Production, 20(2), 93–98. [CrossRef] [PubMed] (In the text)
  99. Thrusfield M, Ortega C, de Blas I, Noordhuizen JP, Frankena K. 2001. Win Episcope 2.0: improved epidemiological software for veterinary medicine. Veterinary Record, 148(18), 567–572. [CrossRef] (In the text)
  100. Vieira TS, Vieira RF, Finger MA, Nascimiento DA, Sicupira PM, Dutra LH, Deconto I, Barros-Filho IR, Dornbusch PT, Biondo AW, Vidotto O. 2013. Seroepidemiological survey of Theileria equi and Babesia caballi in horses from a rural and from urban areas of Paraná State, southern Brazil. Ticks and Tick-Borne Diseases, 4(6), 537–541. [CrossRef] [PubMed] (In the text)
  101. Wang M, Guo W, Igarashi I, Xuan X, Wang X, Xiang W, Jia H. 2014. Epidemiological investigation of Equine Piroplasmosis in China by Enzyme-Linked Immunosorbent Assays. Journal of Veterinary Medicine Science, 76(4), 549–552. [CrossRef] (In the text)
  102. Wise LN, Kappmeyer LS, Mealey RH, Knowles DP. 2013. Review of equine piroplasmosis. Journal of Veterinary Internal Medicine, 27, 1334–1346. [CrossRef] [PubMed] (In the text)
  103. Xu Y, Zhang S, Huang X, Bayin C, Xuan X, Igarashi I, Fujisaki K, Kabeya H, Maruyama S, Mikami T. 2003. Seroepidemiologic studies on Babesia equi and Babesia caballi infections in horses in Jilin province of China. Journal of Veterinary Medicine Science, 65(9), 1015–1017. [CrossRef] (In the text)
  104. Xuan X, Nagai A, Battsetseg B, Fukumoto S, Makala LH, Inoue N, Igarashi I, Mikami T, Fujisaki K. 2001. Diagnosis of equine piroplasmosis in Brazil by serodiagnostic methods with recombinant antigens. Journal of Veterinary Medicine Science, 63(10), 1159–1160. [CrossRef] (In the text)
  105. Xuan X, Chahan B, Huang X, Yokohama N, Makala LH, Igarashi I, Fujisaki K, Maruyama S, Sakai T, Mikami T. 2002. Diagnosis of equine piroplasmosis in Xinjiang province of China by the enzyme-linked immunosorbent assays using recombinant antigens. Veterinary Parasitology, 108(2), 179–182. [CrossRef] [PubMed] (In the text)

Cite this article as: Montes Cortés MG, Fernández-García JL & Habela Martínez-Estéllez MÁ: Seroprevalence of Theileria equi and Babesia caballi in horses in Spain. Parasite, 2017, 24, 14.

All Tables

Table 1.

Prevalence of T. equi and B. caballi antibodies (by IFAT) in horses from different regions of Spain

Table 2.

Serological results by IFAT and cELISA for T. equi (A) and B. caballi (B), respectively.

Table 3.

T. equi and B. caballi prevalence by different diagnostic methods, including geographical distribution and predominant parasite.

All Figures

thumbnail Figure 1.

Map of equine piroplasmosis prevalence by region in Spain. The histogram within each province represents the positive horses using percentages.

In the text

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