Pentaplex PCR assay for rapid differential detection of Babesia bigemina, Theileria annulata, Anaplasma marginale and Trypanosoma evansi in cattle

A comprehensive molecular survey of vector-borne blood parasites in cattle in Kyrgyzstan with a note of the first molecular detection of Anaplasma bovis and Candidatus Anaplasma Camelii

Vector-borne pathogens continue to increase their impact on the livestock industry worldwide. To protect animals against these pathogens, it is very important to identify the species that cause the disease and understand their prevalence. This study aimed to investigate the presence and prevalence of vector-borne pathogens in apparently healthy cattle in different parts of Kyrgyzstan using molecular diagnostic techniques. For this purpose, 531 blood samples were collected from the Osh, Jalal-Abad, and Batken oblasts of Kyrgyzstan. The blood samples were investigated for vector-borne pathogens using PCR, RLB, and RFLP. Moreover, DNA sequence analyses were used to confirm the results of molecular techniques and phylogenetic analyses of these pathogens. 359 (67.61%) out of 531 samples were found to be infected with at least one pathogen, whereas 172 (32.39%) were detected to be negative. Thirteen vector-borne pathogens were detected in cattle blood samples, and the prevalence of these pathogens was as follows: Theileria orientalis (47.83%), T. annulata (25.61%), Babesia major (0.19%), B. occultans (0.38%), Anaplasma phagocytophilum-like 1 (3.20%), A. capra (3.01%), A. centrale (2.82%), A. bovis (1.13%), (A) ovis (0.19%), Candidatus Anaplasma camelii (0.94%), Trypanosoma theileri (19.21%), Mycoplasma wenyonii (6.03%), and Ca. Mycoplasma haemobos (2.64%). Among the positive samples, one pathogen was identified in 189 cattle (35.59%), and co-infections (two or more pathogens) were determined in 170 (32.01%) animals. Theileria parva, T. mutans, (B) bigemina, B. bovis, B. divergens, and A. marginale could not be detected in the study. Anaplasma bovis and Ca. Anaplasma camelii were detected for the first time in the country. This molecular survey provides important epidemiological and genetic data for the vector-borne pathogens in cattle. The results of the study showed that vector-borne pathogens have a significant spread and distribution in cattle in Kyrgyzstan.

Molecular detection of Anaplasma, Babesia, Theileria, and Trypanosoma infection in cattle and buffaloes in India

Tick-borne pathogens pose a significant global threat, causing substantial economic losses to the dairy industry. In India, tropical theileriosis, anaplasmosis, babesiosis, and trypanosomiasis are major hemo-parasitic diseases affecting bovines. A cross-sectional study was conducted to determine the prevalence of hemo-parasites in different farms in India. PCR assays were employed to detect carrier status, using gene targets msp1b, tams1, rap-1, ama1, and ITS1 for A. marginale, T. annulata, B. bovis, B. bigemina, and Trypanosoma species, respectively. Out of the 578 apparently healthy animals screened, 30.45% (95% CI: 26.84-34.32%) were infected with at least one hemo-parasite. Cattle showed an overall positivity of 32.87%, while buffaloes had a prevalence of 15.19%, which was statistically significant (p < 0.001). Interestingly, prevalence was higher in indigenous cattle (47.81%) compared to cross-breeds (25.53%) and exotics (14.62%), with a statistically significant difference (p < 0.001). The prevalence of hemo-parasites varied widely among the farms, ranging from 5.77 to 100%. A. marginale was the most prevalent parasite (23.70% of animals), followed by T. annulata (13.67%), Babesia species (1.90%), and Trypanosoma species (1.56%). Enzootic instability was observed in six of the eight farms, indicating a potential for future outbreaks. Co-infection was detected in 60 out of 176 animals positive for hemo-parasites, with 59 animals co-infected with A. marginale and T. annulata, and only one cross-breed cattle infected with both Anaplasma marginale and Babesia bigemina. The findings highlight the prevalence of hemo-parasites in farms, underscoring the need for whole-herd screening, treatment of infected animals, and improvement in farm management practices to prevent production losses caused by these pathogens.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12639-024-01673-3.

Systematic Review and Meta-Analysis on Piroplasma spp. Infection and Co-infection with Anaplasma marginale in Domestic Ruminants from Algeria

BACKGROUND

Piroplasmosis and anaplasmosis stand out as the primary diseases affecting livestock during periods of tick activity. These vector-borne diseases continue to emerge worldwide, exerting a detrimental impact on both animal health and national economies. The purpose of this study is to assess the prevalence of Piroplasma spp. and its co-occurrence with Anaplasma marginale in domestic ruminants in Algeria.

METHODS

Three databases were systematically reviewed to identify eligible studies for the final meta-analysis, following the PRISMA statement. The 'meta' package in the R software was employed for the meta-analysis with the random effects model chosen for data pooling.

RESULTS

The meta-analysis encompasses 14 research papers spanning a 19-year period (2004-2023). Theileria spp. was identified in all studies, covering 1675 cattle, 190 sheep, and 128 goats, yielding an overall Theileria infection rate of 45% (95% CI 26-65%). Specifically, cattle had a 59% infection rate, while sheep and goats had rates of 18% and 20%, respectively. Babesia spp. was found in nine studies, involving 1183 cattle and 190 sheep, resulting in an overall Babesia infection rate of 7% (95% CI 4-15%), with cattle and sheep having rates of 10% and 3%, respectively. Notably, eight Piroplasma species T. annulata, T. orientalis, T. buffeli, T. equi, Theileria sp., B. bovis, B. bigemina, and B. occultans were detected in cattle, with T. annulata being the most prevalent at 54%. Regional disparities and host factors also impacted infection rates, with higher rates in Northeastern Algeria and among suspected disease cattle. Additionally, gender, age, and breed influenced cattle susceptibility to Theileria infection. Furthermore, six distinct co-infections between Piroplasma spp. and A. marginale were observed, with T. annulata/A. marginale identified in six studies, demonstrating an 8.3% co-infection rate.

CONCLUSION

This analysis offers crucial insights into the current status of Piroplasmosis and its co-infection with A. marginale in Algerian domestic ruminants, providing valuable data for surveillance and prevention strategies.

Molecular characterization and prevalence of bovine hemoprotozoan and rickettsial organism from Bhubaneswar, Eastern India

The blood parasites adversely affect the bovine population and are one of the major hindrances to productivity and health of livestock, globally. This study aimed to study the prevalence of some bovine hemoparasites, their molecular characterization, and associated risk factors in and around Bhubaneswar, a place in Eastern India. Microscopy (Giemsa stained thin blood smear) and polymerase chain reaction (PCR)-based prevalence studies were undertaken for a total of 106bovine blood samples belonging to different breed, age, and sex presented to Veterinary Clinical Complex. DNA was extracted by conventional method and primer targeting msp5 gene (382 bp) for Anaplasma marginale, Tams1 gene (572 bp) for Theileria annulata and VSG RoTat 1.2 gene (110 bp) for Trypanosoma evansi, were used. Sequencing and phylogenetic analysis were also carried out for representative PCR products. The risk factors were correlated with prevalence by logistic regression analysis. Blood smear examination revealed a prevalence an overall of 48.11% (51/106) out of which the prevalence of T. annulata, A. marginale and T. evansi, and concurrent infection were reported to be 26.42%, 10.38%, 3.77%, and 7.55% respectively. All the samples found positive in microscopy were also found positive in PCR. PCR assay revealed an overall prevalence of 73.58% (T. annulata: 37.74%, A. marginale:17.92%, T. evansi: 5.66% and concurrent infection:12.26%). A higher prevalence was observed in the age group of 2-4 years (37.74%), females (61.32%) and cross-bred Jersey (50%). Representative PCR products were sequenced and assigned by GenBank (OL550058: A. marginale; OL604429: T. annulata and OL550059: T. evansi). There is a paucity of disease mapping of these parasites in most parts of the country. The study is probably the first report of molecular characterization of T. evansi and A. marginale from the region which gives some information of possible genetic diversity of the isolates circulating in the region. Future research should include large-scale epidemiological surveys as well as concurrent diagnosis of these hemoparasites for better treatment and control strategies.

Expression profiling of cytokine genes in peripheral blood mononuclear cells from Anaplasma marginale infected and healthy cattle

In this study, changes in expression profiles of genes encoding 14 cytokines (IL1A, IL1B, IL2, IL4, IL6, IL8, IL10, IL12A, IL12B, IL16, IFNA, IFNB, TGFB1, and TNFA) were investigated amongst six Anaplasma marginale infected and six healthy crossbred cattle. Health status of the animals was determined based on clinical signs, blood smear examination and molecular detection using A. marginale-specific primers. Total RNA was isolated from the peripheral blood mononuclear cells of the infected animals as well as the healthy controls, which was further reverse transcribed to cDNA. Primers for real time PCR were designed using Primer3 software and the results were analyzed by the 2-ΔΔCt method with RPS15 and GAPDH as the reference genes. The expression levels of IL1A, IL1B, IL6, IL10, IL12A, IL12B, and TNFA varied significantly between the two groups, with higher expression in the infected cattle. The transcript abundance of IL4, IL16, and TGFB1 did not vary between the diseased and healthy animals. The expression of IL2 and IL8 was higher in the healthy animals, but the results were non-significant. Taken together, this study provides evidence for difference in expression of cytokine genes in response to anaplasmosis in crossbred cattle.

Prediction, Synthesis and Evaluation of a Synthetic Peptide as an Enzyme-Linked Immunosorbent Assay (ELISA) Candidate for Screening of Bovine Antibodies against Theileria annulata

Tick-borne diseases (TBDs) of livestock are endemic across various parts of tropical countries. Theileriosis is one such economically important TBD, caused by the Theileriidae family of organisms, which is transmitted by ticks. Theileria annulata, the causative agent of tropical theileriosis, contributes a significant loss to the dairy sector by causing anorexia, high fever, anemia, inflammatory changes in vital organs and icterus, thus, a loss in milk yield. Though vaccines are available, their protective efficacy is not absolute, and treatment is limited to early diagnosis of the causative agent. Routinely, microscopic identification of piroplasms in the erythrocytes (Giemsa-stained) of infected animals or schizonts in lymph node biopsies are practiced for diagnosis. PCR-based techniques (multiplex, uniplex, nested and real-time) have been reported to perform well in diagnosing active infection. Several attempts have been made using serological assays like Dot blot, ELISA and ICT, but the results were of variable sensitivity and specificity. Recombinant proteins like the Theileria annulata merozoite surface antigen (Tams1) and Theileria annulata surface protein (TaSP) have been explored as antigenic candidates for these assays. In the present study, we predicted an immunogenic peptide, i.e., TaSP-34, from the TaSP using various computational tools. The predicted peptide was custom synthesized. The diagnostic potential of the peptide was assessed by indirect plate ELISA to detect the bovine-IgM against Theileria annulata. Alongside, a recombinant truncated TaSP (rTaSP(tr)) was expressed and purified, which was used to compare the performance of the peptide as a diagnostic candidate. The IgM-based peptide ELISA was 100% sensitive and 92.77% specific as compared to PCR (Tams1 targeting), while 98.04% sensitivity and 97.44% specificity were observed in comparison with rTaSP(tr) ELISA. Almost perfect agreement between peptide ELISA and Tams1 PCR was observed with a Cohen's kappa coefficient (κ-value) of 0.901 and agreement of 95.31%. Further, the κ-value between the peptide ELISA and rTaSP(tr) ELISA was found to be 0.95, and the agreement was 97.65%, which shows a good correlation between the two tests. The findings suggest that the TaSP-34 peptide can be an efficient and new-generation diagnostic candidate for the diagnosis of T. annulata. Furthermore, the peptide can be synthesized commercially at a larger scale and can be a cost-effective alternative for the protein-based diagnostic candidates for T. annulata.

Exploring the Transcriptome Dynamics of In Vivo Theileria annulata Infection in Crossbred Cattle

The molecular changes occurring in the host in response to in vivo Theileria annulata parasitic infection are not well understood. Therefore, the present study investigated the differential expression profiles of peripheral blood mononuclear cells (PBMCs) across Theileria annulata-infected and non-infected crossbred cows. The differential expression profiles from PBMCs of infected and non-infected crossbred cows were generated by RNA sequencing. A marked difference in the expression of genes associated with innate immunity (FTH1, ACTB, ISG15) was observed between the two groups. The over-represented pathways in Theileria annulata-infected cows were associated with the immune system and regulation of the mitotic cycle. Enriched genes and pathways in non-infected animals were associated with the maintenance of chromatin integrity and cell structure. The highly connected genes identified in this study form potential candidates for further investigation into host-parasite interactions in cattle. An improved understanding of the transcriptomic dynamics during theileriosis would lead to underpinning molecular level differences related to the health status of cattle.

Unraveling the genetic mechanisms governing the host response to bovine anaplasmosis

Bovine anaplasmosis caused by Anaplasma marginale is a tick-borne disease of livestock with widespread prevalence and huge economic implications. In order to get new insights into modulation of host gene expression in response to natural infections of anaplasmosis, this study is the first attempt that compared the transcriptome profiles of peripheral blood mononuclear cells (PBMCs) of A. marginale infected and healthy crossbred cattle. Transcriptome analysis identified shared as well as unique functional pathways in the two groups. Translation and structural constituent of ribosome were the important terms for the genes abundantly expressed in the infected as well as healthy animals. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis of the differentially expressed genes revealed that immunity and signal transduction related terms were enriched for the up-regulated genes in the infected animals. The over-represented pathways were cytokine-cytokine receptor interaction and signaling pathways involving chemokines, Interleukin 17 (IL17), Tumour Necrosis Factor (TNF), Nuclear Factor Kappa B (NFKB) etc. Interestingly, many genes previously associated with parasite-borne diseases such as amoebiasis, trypanosomiasis, toxoplasmosis, and leishmaniasis were profusely expressed in the dataset of the diseased animals. High expression was also evident for the genes for acute phase response proteins, anti-microbial peptides and many inflammatory cytokines. Role of cytokines in mediating communication between immune cells was the most conspicuous gene network identified through the Ingenuity Pathway Analysis. This study provides comprehensive information about the crosstalk of genes involved in host defense as well as parasite persistence in the host upon infection with A. marginale.

Validation of stable reference genes in peripheral blood mononuclear cells for expression studies involving vector-borne haemoparasitic diseases in bovines

Normalization of gene expression data using appropriate reference genes is critical to diminish any technical bias in an experiment involving quantitative real-time PCR (qPCR). To the best of our knowledge, this is the first report offering a systematic assessment of 14 potential reference genes (RPLP0, ACTB, RPS28, YWHAZ, SDHA, PPIA, RPS9, RPS15, UXT, GAPDH, B2M, BACH1, HMBS, and PPIB) for the identification of the most stable normalizers for qPCR of target genes in peripheral blood mononuclear cells (PBMCs) of bovines for vector-borne haemoparasitic diseases such as anaplasmosis, babesiosis, theileriosis, and trypanosomiasis. A total of 38 blood samples were collected from healthy as well as diseased cattle and buffaloes representing different haemoparasitic diseases. RNA isolated from the PBMCs was subjected to qPCR for the 14 prospective internal control genes. The comprehensive ranking of the genes was accomplished by the RefFinder tool that integrates the results of three algorithms (geNorm, NormFinder, and BestKeeper) and the comparative C_T method. RPS15, B2M, and GAPDH were ranked to be the most stable genes, whereas, PPIA and HMBS emerged to be the least suitable genes. Validation of the selected reference genes by the qPCR analysis of two immunity genes, ISG15 and GPX7 was congruent with the observations of this study. We recommend that a panel of three reference genes including RPS15, B2M, and GAPDH could prove useful in delineating the transcriptional landscape of PBMCs for vector-borne haemoparasitic diseases in bovines.

Multiplex PCR for rapid differential diagnosis of co-prevalent species of Theileria (Theileria annulata and Theileria orientalis) in cattle

Theileriosis is a tick-borne disease that causes enormous losses in the dairy industry. There are several species of Theileria that can infect bovines. Generally, more than one species are prevalent in any geographical area; thus, chances of co-infections are high. Differentiation of these species may not be possible by microscopic examination or serological tests. Therefore, in this study, a multiplex PCR assay was standardized and evaluated for rapid and simultaneous differential detection of two species of Theileria viz., Theileria annulata and Theileria orientalis. Species-specific primers were designed to target the merozoite piroplasm surface antigen gene (TAMS1) of T. annulata and the major piroplasm surface protein gene of T. orientalis, yielding specific amplicon of 229 bp and 466 bp, respectively. The sensitivity of multiplex PCR was 10² and 10³ copies for T. annulata and T. orientalis, respectively. The simplex and multiplex PCRs were specific and showed no cross-reactivity with other hemoprotozoa for either primer. For comparative evaluation, blood samples from 216 cattle were tested by simplex and multiplex PCR for both species. Using multiplex PCR, 131 animals were found infected for theileriosis, of which 112 were infected with T. annulata, five were infected with T. orientalis, and 14 had mixed infections. This is the first report of T. orientalis from Haryana, India. Representative sequences of T. annulata (ON248941) and T. orientalis (ON248942) were submitted in GenBank. The standardized multiplex PCR assay used in this study was specific, sensitive, for the screening of field samples.

Occurrence of ticks and tick-borne mixed parasitic microbiota in cross-bred cattle in District Lahore, Pakistan

The present study was focused on the incidence of ticks and tick-borne diseases (TTBD) in cross-bred cattle (Friesian x Sahiwal) of two farms (n = 2548) in district Lahore, Pakistan. We collected total of 572 ticks (adults and nymphs) and blood samples (10 ml) for microscopic i.e., blood smear test - Giemsa Stain (BST) and molecular analysis; Reverse Line Blot-General Primer-PCR (RLB-PCR) and Specie Specific Primer PCR (SP-PCR) from infested cattle (n = 100) from months of April to September. Results: The tick specie identified was Rhipicephalus microplus at both farms, with significant difference in infestations rate amongst both farms (p< 0.0001). The cross-bred cattle having higher ratio of Friesian blood and lower ratio of Sahiwal blood were mostly infested by ticks (p < 0.0458) and haemoparasites (p <0.474) and vice versa. The SP-PCR showed higher number of haemoparasites infection than BST, which revealed 16% T. annulata (p < 0.0001 and k value 0.485, 0.0001), 51% B. bigemina (p < 0.0001 and k value 0.485, 0.0001) and 15% A. marginale (p < 0.001 and k value 0.207, 0.001), respectively. The single infection with B. bigemina was 34% (n = 34/100) and A. marginale 6% (n = 6/100). The double infection with T. annulata/B. bigemina was 8% (n = 8/100) and B. bigemina/A. marginale 1% (n = 1/100). Whereas the triple infection with T. annulata/B. bigemina/A .marginale was 8% (n = 8/100). The phylogenetic study of isolated sequence of T. annulata revealed close homology to isolates from Iran (87%), B. bigemina to isolates from Cuba (94 to 100%) and A. marginale with isolates from Pakistan (99 to 98%).

18S rRNA Gene-Based Piroplasmid PCR: An Assay for Rapid and Precise Molecular Screening of Theileria and Babesia Species in Animals

PURPOSE

The parasites of genera such as Babesia and Theileria are called piroplasmids due to the pear-shaped morphology of the multiplying parasite stages in the blood of the vertebrate host. Because of the enormous number of parasite species and the challenges of multiplex PCR, initial screening of samples using piroplasmid-specific PCR may be a more cost-effective and efficient technique to identify parasite species, especially during epidemiological studies. Accordingly, 18S rRNA PCR was standardized and optimized on common piroplasmids of different animals like cattle, buffaloes, sheep, goats, dogs, horses, and leopards.

METHODS

Bloods samples from 1250 animals were collected from different animals in Junagadh district of Gujarat, India. 18S rRNA PCR was standardized and optimized as a primary method for molecular screening of piroplasms in domestic and wild animals. The method was checked for its analytical sensitivity and specificity. Parasite species-specific PCR and sequencing was used to validate the test. Moreover, in-silico restriction enzyme (RE) analysis was also done to assess its applicability in PCR-RFLP.

RESULTS

Piroplasm infections were recorded in 63.3% of animals in Junagadh. The 18S rRNA PCR detected the piroplasmid DNA in as low as 39 picograms (pg) of whole blood genomic DNA isolated from microscopically Theileria positive blood samples and no reactivity was recorded from common but unrelated haemoparasites viz., Trypanosoma evansi, Hepatozoon spp., Anaplasma spp., and Ehrlichia canis was observed. The 18S rRNA PCR assay findings were confirmed by species-specific PCR and sequencing. Analysis of different sequences generated using 18S rRNA PCR revealed that the amplicon size of Babesia spp. is nearly 400 bp (393-408 bp) whereas Theileria spp. were more than 400 bp (418-424 bp). The percentage of sequence divergence among Babesia and Theileria spp. was 7.3-12.2% and 0.7-12.2%, respectively. In-silico restriction enzyme (RE) analysis reveals the presence of at least one site for a commercially available RE in 18S rRNA fragments of every parasite, which can differentiate it from its congeners.

CONCLUSIONS

The presented universal oligonucleotide-based PCR assay provides a highly sensitive, specific, cost-effective, and rapid diagnostic tool for the initial screening of piroplasmids infecting domestic and wild animals and is potentially helpful for large-scale epidemiological studies.

Development and standardization of a Loop-mediated isothermal amplification (LAMP) test for the detection of Babesia bigemina

Bovine babesiosis is a tick-borne disease caused by protozoan parasites of the genus Babesia. Babesia bigemina is one of the most prevalent and economically important parasite species that infects cattle because of its impact on the meat and milk production industry. Effective disease control strategies should include detection of reservoir animals and early and specific pathogen detection using rapid, economical, sensitive, and specific detection techniques. The loop-mediated isothermal amplification technique (LAMP) is a one-step molecular reaction that amplifies DNA sequences with high sensitivity and specificity under isothermal conditions and requires no special equipment. The results can be observed by the naked eye as color changes. The aim of this work was to develop and standardize the LAMP technique for B. bigemina detection and its visualization using hydroxynaphtol blue. For this situation, primers were designed from the conserved sequences of the B. bigemina ama-1 gene. The results showed that at 63 °C in 1 h and under standardized conditions, this technique could amplify B. bigemina DNA as indicated by the characteristic colorimetric change. Sensitivity evaluation indicated that DNA was amplified at a 0.00000001% parasitemia, and it was demonstrated that this technique specifically amplified the DNA of B. bigemina. Additionally, this technique could amplify DNA from 10 strains of B. bigemina from three different countries. It is concluded that the LAMP technique as modified in our case could specifically amplify B. bigemina DNA and shows high sensitivity, does not cross-react with related organisms, and the product is observed by 60 min of reaction time based on color changes. This report is the first LAMP report that uses sequences that are conserved between strains of the ama-1 gene, demonstrates the results by color changes using hydroxynaphtol blue. We propose LAMP as a rapid and economical alternative method for the molecular detection of B. bigemina.

18S rRNA Gene-Based Piroplasmid PCR: An Assay for Rapid and Precise Molecular Screening of Theileria and Babesia Species in Animals

Purpose

The parasites of genera such as Babesia and Theileria are called piroplasmids due to the pear-shaped morphology of the multiplying parasite stages in the blood of the vertebrate host. Because of the enormous number of parasite species and the challenges of multiplex PCR, initial screening of samples using piroplasmid-specific PCR may be a more cost-effective and efficient technique to identify parasite species, especially during epidemiological studies. Accordingly, 18S rRNA PCR was standardized and optimized on common piroplasmids of different animals like cattle, buffaloes, sheep, goats, dogs, horses, and leopards.

Methods

Bloods samples from 1250 animals were collected from different animals in Junagadh district of Gujarat, India. 18S rRNA PCR was standardized and optimized as a primary method for molecular screening of piroplasms in domestic and wild animals. The method was checked for its analytical sensitivity and specificity. Parasite species-specific PCR and sequencing was used to validate the test. Moreover, in-silico restriction enzyme (RE) analysis was also done to assess its applicability in PCR–RFLP.

Results

Piroplasm infections were recorded in 63.3% of animals in Junagadh. The 18S rRNA PCR detected the piroplasmid DNA in as low as 39 picograms (pg) of whole blood genomic DNA isolated from microscopically Theileria positive blood samples and no reactivity was recorded from common but unrelated haemoparasites viz., Trypanosoma evansi, Hepatozoon spp., Anaplasma spp., and Ehrlichia canis was observed. The 18S rRNA PCR assay findings were confirmed by species-specific PCR and sequencing. Analysis of different sequences generated using 18S rRNA PCR revealed that the amplicon size of Babesia spp. is nearly 400 bp (393–408 bp) whereas Theileria spp. were more than 400 bp (418–424 bp). The percentage of sequence divergence among Babesia and Theileria spp. was 7.3–12.2% and 0.7–12.2%, respectively. In-silico restriction enzyme (RE) analysis reveals the presence of at least one site for a commercially available RE in 18S rRNA fragments of every parasite, which can differentiate it from its congeners.

Conclusions

The presented universal oligonucleotide-based PCR assay provides a highly sensitive, specific, cost-effective, and rapid diagnostic tool for the initial screening of piroplasmids infecting domestic and wild animals and is potentially helpful for large-scale epidemiological studies.

Supplementary Information

The online version contains supplementary material available at 10.1007/s11686-022-00625-2.

Molecular epidemiology, phylogenetic analysis and risk assessment of Anaplasma marginale from naturally infected bovines of Punjab (India)

Anaplasmosis, an infectious vector borne rickettsial disease caused by different species of Anaplasma transmitted through mechanical and biological (tick) processes has a great concern to livestock industry due to its associated economic losses. The current cross sectional comprehensive epidemiological study was conducted from August 2020 to November 2021 on 391 (277 cattle and 114 buffaloes) bovines from different districts of five agro climatic zones of Punjab state. Classical microscopic examination of Romanowsky stained blood smears showed an occurrence of 13.00%, while DNA amplification targeting major surface protein (msp5) of Anaplasma marginale revealed the 382 bp amplicon in 32.48% samples. Zone based molecular prevalence of A. marginale was highest in the Undulating zone (41.93%) and least in the Sub-Mountain zone (18.84%). The prevalence in Central plain zone, Western plain zone, and Western zone were 40.15, 30.95 and 29.91%, respectively. An overall molecular prevalence of A. marginale was 34.52, 32.75 and 20.0% in young, adults and calves, respectively, the difference being non-significant. Anaplsma marginale was more prevalent in unorganized farms (38.22%; 60/157) than organized farms (28.63%; 66/234). Risk factors analysis revealed young, female cattle at unorganized farms were more prone to anaplasmosis. Out of 127 positive samples, four samples were customed to sequencing revealed 98-99% homology with published sequences for other available global isolates. Multi-single nucleotide polymorphisms (SNP) were observed in the sequence of two samples when aligned with the reference sequence from the NCBI database (CP023731).

Seasonal survey, risk factor's analysis and genotyping of Theileria annulata infecting cattle in Punjab province, Pakistan

Theileriosis is one of the most frequently reported tick borne diseases in tropical and subtropical regions and leads to annual economic losses, such as the reduced dairy products and increased casualties. Tropical theileriosis is caused by Theileria annulata and the present study was designed to improve our knowledge of Theileria annulata infection in Pakistani cattle. In order to assess the prevalence of Theileria annulata on cattle from Multan district in the Punjab province (Pakistan) according to seasons and other risk factors, a total of 1020 blood samples (340 samples each from cross, Holstein Frisian and Sahiwal breed) were collected between 2020 and 2022. Based on Tams-1 partial sequence amplification, the overall T. annulata prevalence was estimated at 11.3% (115/1020). The highest prevalence was observed in autumn season (14.1%), followed by winter (12.9%), summer (11.4%) and spring (6.7%) season. Sahiwal cattle were most susceptible to T. annulata infection (13.2%) followed by Crossbred (11.8%) and Holstein Frisian (8.8%). Epidemiological factor analysis revealed that female cattle, cattle rose with other dairy animals at farm, tick infested cattle, and cattle raised with dogs infested with ticks were associated with the prevalence of T. annulata. White blood cells, lymphocyte (%), Monocyte (%) hemoglobin, mean cell hemoglobin, mean corpuscular hemoglobin concentration, and platelet count were significantly affected blood parameters in T. annulata positive cattle of all three breeds. Representative partial Tams-1 sequences of four Pakistani T. annulata isolates revealed a single genotype genetically close to those infecting cattle from neighboring countries like Iran, Turkey and Egypt. Longitudinal survey and phylogenetic positioning of T. annulata is recommended for epidemiological correlation, diagnosis and treatment of theileriosis in such an agricultural region of Pakistan.

Development of highly sensitive one step-PCR tests for improved detection of B. bigemina and B. bovis

Bovine babesiosis caused by Babesia bigemina and B. bovis is an economically relevant tick-borne disease distributed over tropical and subtropical world regions. Animals that recover from the clinical disease can remain persistently infected, and those carriers are epidemiologically relevant since they can act as a source of infection to other animals through the tick bite. According to the manual of the World Organisation for Animal Health (OIE), the recommended molecular diagnosis test for both parasites is a nested polymerase chain reaction (nPCR) based on an amplification of a fragment of the rap-1 gene. Since nPCRs are time consuming, have a higher cost and risk of contamination, we propose a single step PCR for B. bigemina (BbiVESA) and B. bovis (BboVESA) based on the amplification of the multi-copy ves-1α gene. We developed these methods and we achieved a detection limit of 1 × 10^-12 % parasitemia for B. bigemina and of 1 × 10^-6 % for B. bovis using reference strains, which compared to the reference OIE tests, results in an improvement in sensitivity of six orders for B. bigemina. Finally, we tested 48 field samples from a babesiosis enzootic region where we were able to detect a higher proportion of positive animals with both VESA methods than with the reference rap-1 nPCRs. This difference was statistically significant for each Babesia species. Concordance between both diagnostic schemes based on Cohen's kappa coefficient showed minimal to non-agreement (κ = 0.32) for B. bigemina and non-agreement (κ = 0.16) for B. bovis since BbiVESA and BboVESA PCR tests showed a significantly higher detection capacity. In conclusion, the high sensitivity of the assay, together with the lower demand of time and reagents make the VESA PCR methods developed here a valuable diagnostic tool for the molecular detection and epidemiological survey of both Babesia pathogens.

Prevalence of antibodies to Anaplasma in cattle and buffaloes of different organized herds in India

Bovine anaplasmosis is one of the most important tick borne disease in ruminants causing huge economic loss to the dairy industry. A cross-sectional study was carried out to detect serum antibodies to Anaplasma infection in cattle and buffaloes housed in 14 organized herds located at various climatic zones spreading over 9 different states in India. A total of 911 serum samples, collected from 667 cattle and 244 buffaloes, were subjected to a competitive enzyme linked immune-sorbent assay detecting an epitope of major surface protein 5 (MSP5) of Anaplasma. The overall true prevalence was 48.72% (95% CI 45.13-52.32%). The prevalence rate was higher in cattle (51.58%) than buffaloes (40.89%) and the difference was statistically significant (p < 0.05). Indigenous cattle (59.30%) showed higher seropositivity than crossbreed (57.16%) and exotic cattle breeds (42.28%). Although statistically not significant, female (52.37%) showed higher seropositivity than male (46.43%). Similarly, significant difference in prevalence (p < 0.05) was observed for animals reared in different climatic zones with highest prevalence recorded in arid zone (90.49%) and lowest in semi-arid zone (29.83%). Very wide variation in prevalence (9.95-100%) was recorded between farms. The present study indicates endemicity of Anaplasma in India, similar to other tropical and sub-tropical countries of the world. Endemic instability was recorded in some of the studied farms suggesting possibility of outbreak of new clinical cases resulting in economic loss. Therefore, suitable policies and procedures for prevention and control of Anaplasma infection should be adopted in these farms.