Tick-borne Pathogens In Cattle Research Articles

Genetically modified live vaccine offers protective immunity against wild-type Anaplasma marginale tick-transmission challenge

Anaplasma marginale is a tick-borne pathogen of cattle that causes bovine anaplasmosis in tropical and subtropical regions throughout the world. Killed vaccines derived from infected erythrocytes have been used for control of this disease with limited success. Recently, we described a targeted deletion mutation in the phage head-to-tail connector protein gene of A. marginale which caused bacterial attenuation in vivo and provided protection as a modified live vaccine (MLAV). Following intravenous injection of susceptible steers, the MLAV induced protective immunity against disease progression. In the current study, we demonstrated that the immunity resulting from MLAV in cattle prevents the disease progression resulting from virulent A. marginale intrastadial transmission from infected Dermacentor variabilis male ticks. The nonimmunized control steers receiving the infection from ticks developed fever, lethargy, and inappetence for several days post tick exposure with significant decreases in the packed cell volume and increases in bacteremia. In contrast, the MLAV immunized steers remained healthy after being challenged with infected ticks and this group of animals had a significant reduction in bacteremia as compared with the controls. This study demonstrated that the A. marginale MLAV provided protection against acute tick-transmitted anaplasmosis, in addition to protection documented in steers challenge-exposed with infected blood as reported previously.

Molecular detection and phylogenetic analysis of tick-borne pathogens in cattle from southern Malawi.

Tick-borne diseases (TBDs) pose a major hindrance to livestock production in countries with limitedresources. Effective prevention and management of TBDs require a thorough understanding of disease vectorsand pathogens. However, there is limited information on studies of bovine tick-borne pathogens (TBPs) using molecular methods in Malawi. This study aimed to detect TBPs of cattle populations in southern Malawi, which has the largest cattle population in the country. A total of 220 blood samples from apparently healthy cattle were collected in six districts, and werescreened for selected TBPs using polymerase chain reaction (PCR). The overall detection rate of TBPs was 72.3%. Among the detected pathogens, Babesia bigemina hadthe highest detection rate (34.5%), followed by Anaplasma marginale (23.2%), Anaplasma phagocytophilum(22.3%), Theileria taurotragi (22.3%), Theileria parva (15.5%),Anaplasma bovis (9.6%), Babesia bovis (7.3%),Theileria mutans (4.1%), and Babesia naoakii (2.7%). Among the positive samples, 64.2% were found to be co-infected with two or more TBPs, with the highest number of seven pathogens detected in a single sample. Thestudy documents the existence of A. phagocytophilum, B. bovis, and B. naoakii in Malawian cattle for the first time. The findings herein demonstrate a significant burden of TBPs on cattle in Malawi, which gives a challenge in combating TBDs. The high TBP burden, along with the high co-infection frequencies in Malawian cattle necessitates the urgency to implement effective control strategies to enhance cattle production in the country.

Dynamics of Infections in Cattle and Rhipicephalus microplus: A Preliminary Study.

Tick-borne pathogens (TBPs) pose a significant threat to livestock, including bovine species. This study aimed to investigate TBPs in cattle and ticks across four sampling points, utilizing real-time microfluidic PCR. The results revealed that Rhipicephalus microplus ticks were found infesting all animals. Among the detected TBPs in cattle, Anaplasma marginale was the most frequently identified, often as a single infection, although mixed infections involving Rickettsia felis, uncharacterized Rickettsia sp., and Anaplasma sp. were also observed. In ticks, A. marginale was predominant, along with R. felis, Rickettsia sp., and Ehrlichia sp. It is noteworthy that although A. marginale consistently infected all cattle during various sampling times, this pathogen was not detected in all ticks. This suggests a complex dynamic of pathogen acquisition by ticks. A phylogenetic analysis focused on the identification of Anaplasma species using amplified 16S rDNA gene fragments revealed the presence of A. marginale and Anaplasma platys strains in bovines. These findings underscore the presence of multiple TBPs in both cattle and ticks, with A. marginale being the most prevalent. Understanding the dynamics and phylogenetics of TBPs is crucial for developing effective control strategies to mitigate tick-borne diseases in livestock.

Acaricide Resistance Development in Rhipicephalus (Boophilus) microplus (Acari: Ixodidae) Populations against Amitraz and Deltamethrin on Communal Farms of the King Sabata Dalindyebo Municipality, South Africa.

Chemical acaricides are widely used to control ticks and tick-borne pathogens in cattle. However, prolonged and indiscriminate use of these chemicals inevitably leads to the selection of resistant ticks. In-vitro bioassays (adult and larval immersion tests) were conducted to assess amitraz and deltamethrin resistance in Rhipicephalus (Boophilus) microplus populations from communal farms of the King Sabata Dalindyebo municipality of South Africa. Data generated on percentage inhibition of oviposition (%IO) revealed that all the tick populations assessed showed resistance (%IO ≤ 95%) to at least one of the acaricides. All six tick populations assessed for efficacy (%IO ≥ 95%) at the DD) with deltamethrin were resistant (%IO ≤ 95%) and only one of the six tick populations assessed for efficacy with amitraz was susceptible. Based on the resistance ratios (RR), the adult immersion test detected amitraz and deltamethrin resistance in three (RR ranging from 2.30 to 3.21) and five (RR ranging from 4.10 to 14.59) of the six tick populations, respectively. With the larval immersion test, deltamethrin and amitraz resistance (larval mortality < 90% at the DD) was detected in all four and three of four R. (B.) microplus populations assessed, respectively. These data are critical for the design of an effective and sustainable tick control strategy on the communal farms.

Epidemiology of tick-borne pathogens of cattle and tick control practices among mixed farming and pastoral communities in Gairo and Monduli districts, Tanzania.

Tick-borne diseases including East Coast fever, anaplasmosis and babesiosis constitute a major constraint to improving livestock production worldwide, including Tanzania. Determination of the prevalence and factors associated with the occurrence of pathogens in cattle is important for informed decision making on the control and prevention of these diseases. However, little is known about the epidemiology of these pathogens in cattle in some regions of Tanzania. Therefore, this study aimed at establishing the prevalence of Anaplasma marginale, Babesia bigemina, Babesia bovis and Theileria parva in cattle, determine the risk factors associated with infection with these pathogens and also to assess tick control practices in Gairo and Monduli districts of Tanzania. Out of the 520 cattle sampled, the majority (82.9%) were infested with ticks of different species, predominated by Rhipicephalus decoloratus (42.7%), Amblyomma variegatum (31.3%), Rhipicephalus pulchellus (23.1%) and Rhipicephalus appendiculatus (17.7%). Other ticks that were found on cattle included Rhipicephalus microplus (15.8%), Amblyomma gema (13.8%), Rhipicephalus evertsi (12.9%), Amblyomma lepidum (8.1%), Hyalomma truncatum (2.9%) and Hyalomma albiparmatum (2.1%). On microscopy 23 (4.4%) of 520 cattle were positive for hemoparasites. Of the 23 positive cattle, 13 (2.5%), 6 (1.2%) and 3 (0.6%) were monolithically infected with A. marginale, T. parva, and B. bovis respectively, while one (0.2% %) had co-infections of T. parva and A. marginale. The number of positive cattle increased to 184 (35.4%), when they were subjected to detection with PCR. This included the 23 samples that were positive on microscopy. Based on PCR, the overall prevalence of the pathogens from the two districts was 11.5%, 11.2%, 6.2% and 2.5% for B. bigemina, A. marginale, T. parva and B. bovis, respectively. Hemoparasite co-infection occurred in 6.9% of the cattle examined. The prevalence of co-infections was 2.7%, 4%, and 0.02% for T. parva/A. marginale, B. bigemina/A. marginale and B. bigemina/A. marginale/T. parva, respectively. Cattle with co-infections had significantly lower (p<0.005) mean packed cell volume as compared to cattle with mono-infections. The majority (96%) of cattle examined were subjected to different methods of tick control. A number of risk factors were shown to be associated with the occurrence of tick-borne pathogens in cattle. Higher prevalence of A. marginale may be due to its wide range of biological and mechanical transmission. These findings could be used to strengthen future control programs for ticks and tick-borne diseases in the study areas.

Protozoan and Rickettsial Pathogens in Ticks Collected from Infested Cattle from Turkey.

Diseases caused by tick-transmitted pathogens including bacteria, viruses, and protozoa are of veterinary and medical importance, especially in tropical and subtropical regions including Turkey. Hence, molecular surveillance of tick-borne diseases will improve the understanding of their distribution towards effective control. This study aimed to investigate the presence and perform molecular characterization of Babesia sp., Theileria sp., Anaplasma sp., Ehrlichia sp., and Rickettsia sp. in tick species collected from cattle in five provinces of Turkey. A total of 277 adult ticks (males and females) were collected. After microscopic identification, tick pools were generated according to tick species, host animal, and sampling sites prior to DNA extraction. Molecular identification of the tick species was conducted through PCR assays. Out of 90 DNA pools, 57.8% (52/90) were detected to harbor at least 1 pathogen. The most frequently-detected pathogens were Babesia bovis, with a minimum detection rate of 7.9%, followed by Ehrlichia sp. (7.2%), Theileria annulata (5.8%), Coxiella sp. (3.3%), Anaplasma marginale (2.5%), Rickettsia sp. (2.5%), and B. occultans (0.7%). Rickettsia sp. identified in this study include Candidatus Rickettsia barbariae, R. aeschlimannii, and Rickettsia sp. Chad. All sequences obtained from this study showed 99.05–100% nucleotide identity with those deposited in GenBank (query cover range: 89–100%). This is the first molecular detection of Rickettsia sp. Chad, a variant of Astrakhan fever rickettsia, in Turkey. Results from this survey provide a reference for the distribution of ticks and tick-borne pathogens in cattle and expand the knowledge of tick-borne diseases in Turkey.

Molecular prevalence and risk factors associated with tick-borne pathogens in cattle in western Kenya

BackgroundTick-borne pathogens (TBPs) are of global importance, especially in sub-Saharan Africa where they represent a major constraint to livestock production. Their association with human disease is also increasingly recognized, signalling their zoonotic importance. It is therefore crucial to investigate TBPs prevalence in livestock populations and the factors associated with their presence. We set out to identify TBPs present in cattle and to determine associated risk factors in western Kenya, where smallholder livestock production is important for subsistence and market-driven income.ResultsTick-borne pathogen infections in blood samples collected from cattle at livestock markets and slaughterhouses between May 2017 and January 2019 were identified by high-resolution melting analysis and sequencing of PCR products of genus-specific primers. Of the 422 cattle sampled, 30.1% (127/422) were infected with at least one TBP, while 8.8% (37/422) had dual infections. Anaplasma spp. (19.7%) were the most prevalent, followed by Theileria (12.3%), Ehrlichia (6.6%), and Babesia (0.2%) spp. Sequence analysis of the TBPs revealed them to be Anaplasma platys-like organisms (13.5%), Theileria velifera (7.4%), Anaplasma marginale (4.9%), Theileria mutans (3.1%), Theileria parva (1.6%), and Babesia bigemina (0.2%). Ehrlichia ruminantium, Rickettsia spp., and arboviruses were not detected. Exotic breeds of cattle were more likely to be infected with A. marginale compared to local breeds (OR: 7.99, 95% CI: 3.04–22.02, p < 0.001). Presence of ticks was a significant predictor for Anaplasma spp. (OR: 2.18, 95% CI: 1.32–3.69, p = 0.003) and Ehrlichia spp. (OR: 2.79, 95% CI: 1.22–7.23, p = 0.022) infection. Cattle sampled at slaughterhouses were more likely to be positive for Anaplasma spp. (OR: 1.64, 95% CI: 1.01–2.70, p = 0.048) and A. marginale (OR: 3.84, 95% CI: 1.43–12.21, p = 0.012), compared to those sampled at livestock markets.ConclusionThis study reports TBP prevalence and associated risk factors in western Kenya, factors which are key to informing surveillance and control measures.

Molecular Survey of Babesia and Anaplasma Infection in Cattle in Bolivia.

Latin American countries produce more than a quarter of the world’s beef and are a major global supplier of livestock protein. Tick-borne diseases (TBDs) are a major constraint to the livestock industry worldwide, including in Latin America. The aim of this study was to detect and characterise tick-borne pathogens in cattle from Santa Cruz, Bolivia, where no detailed epidemiological data are available. Blood samples were collected from 104 cattle. Apicomplexan parasites were detected by nested PCR amplification of the 18S ribosomal RNA gene (rDNA), and Anaplasmataceae was screened by the PCR amplification of 16S rDNA, followed by characterisation based on the heat shock protein and citrate synthase gene sequences. Babesia infection was observed in nine cattle (one Babesia bovis and eight Babesia bigemina), while Anaplasmataceae infection was detected in thirty-two cattle. A sequencing analysis confirmed the presence of Anaplasma marginale and Anaplasma platys-like. These results provide the first molecular evidence for the four above-mentioned tick-borne pathogens in cattle in Bolivia. This information improves our understanding of the epidemiology of TBDs and will help in formulating appropriate and improved pathogen control strategies.

Molecular detection of selected tick-borne pathogens infecting cattle at the wildlife–livestock interface of Queen Elizabeth National Park in Kasese District, Uganda

In Uganda, ticks and tick-borne diseases (TBDs) pose a big challenge to farmers. They reduce cattle productivity and cause severe economic damage. Several studies have documented the prevalence of tick-borne pathogens in cattle; however, their genetic characteristics and the role of wildlife-livestock interaction in the epidemiology of the TBDs are not well documented. This study assessed the prevalence and genetic diversity of various tick-borne pathogens (TBPs) as well as the risk factors associated with the occurrence of TBPs in blood samples of 208 randomly selected cattle from 16 farms located around Queen Elizabeth National Park (QENP) in Kasese District in western Uganda. Farming practices, disease challenges, and the level of wildlife-livestock interactions were assessed by a questionnaire survey amongst farm owners. Polymerase chain reaction (PCR) assays revealed that 62.9% (131/208) cattle samples were positive for one or more pathogens. Using specific PCR assays, we detected Theileria spp., Theileria parva, Anaplasma marginale, Anaplasma platys-like, and Babesia bigemina at 50.5%, 27.9%, 19.2%, 11.5% and 8.7%, respectively. We also confirmed the infection of samples by Theileria velifera and Theileria mutans after sequencing the Theileria spp. 18S rRNA gene. The risk factors associated with the occurrence of TBPs included communal grazing, herd size, age, and proximity to QENP. Phylogenetic analysis of the T. parva p104 gene showed a high identity to the previous isolates from Uganda and other East African countries and clustered closer to the buffalo (Syncerus caffer) isolates, suggesting a possible cross-species transmission. The sequences of A. marginale groEL and B. bigemina RAP-1a formed well-supported clades with high identities to the previous isolates identified from central and eastern Uganda. The isolates obtained from A. phagocytophilum 16S rRNA gene sequences showed relationship with A. platys-like, Anaplasma sp., uncultured Anaplasma species and A. phagocytophilum isolates from Africa, Asia, Europe, and the USA. The findings of the present study showed that TBDs are still a burden to farmers and that management practices in this area may increase the transmission of pathogens between livestock and wildlife.

Molecular Characterization of Ticks and Tick-Borne Pathogens in Cattle from Khartoum State and East Darfur State, Sudan.

Ticks transmit many pathogens with public health and veterinary importance. Despite the wide distribution of tick-borne pathogens in Sudan, the information on the tick–pathogen relationship needs to be updated, particularly using modern molecular techniques. This cross-sectional study, conducted between September and November 2019, used morphology, PCR, and sequencing to confirm the identity of adult cattle ticks (male and female; n = 536) from Khartoum State (n = 417) and East Darfur State (n = 119). Moreover, the presence of Theileria annulata, Babesia bigemina, B. bovis, Anaplasma marginale, and Ehrlichia ruminantium was detected and confirmed in each tick using species-specific PCR or nested PCR and sequencing. The most economically important tick genera, Rhipicephalus, Hyalomma, and Amblyomma, were prevalent in the study area, and 13 different tick species were identified. The most prevalent tick species were Rhipicephalus evertsi evertsi (34.3%) and Hyalomma anatolicum (57.3%) in Khartoum State, and Rhipicephalus annulatus (27%), Rhipicephalus decoloratus (25%), and Hyalomma rufipes (29%) in East Darfur State. We detected all five pathogens in both states. To the best of our knowledge, this is the first study to report the presence of E. ruminantium, its vector Amblyomma variegatum, and B. bovis in Khartoum State. Further, this is the first report on most tick and pathogen species identified in East Darfur State. Our findings indicate the migration of some tick and pathogen species beyond their distribution areas in the country, and this consideration is necessary to develop future control strategies.

First report of Theileria annulata in Nigeria: Findings from cattle ticks in Zamfara and Sokoto States

BackgroundTicks and tick-borne pathogens (TBPs) represent a significant economic burden to cattle farming in sub-Saharan Africa including Nigeria. However, in the northern part of this country, where the largest livestock population resides, little is known about the contemporary diversity of ticks and TBPs. This area is particularly vulnerable to climate change, undergoing marked transformation of habitat and associated flora and fauna that is also likely to include ticks. This study aimed to document the occurrence of tick species and Apicomplexan TBPs in cattle from north-western Nigeria.MethodsIn 2017, ticks were collected from cattle in Zamfara and Sokoto States and identified morphologically. Additionally, a subset of ticks was screened molecularly for the detection of apicomplexan DNA.ResultsA total of 494 adult ticks were collected from 80 cattle in Zamfara and 65 cattle in Sokoto State. Nine tick species were encountered, among which the presence of one, Hyalomma turanicum, had not previously been recorded in Nigeria. Hyalomma rufipes was the most prevalent tick infesting cattle in Zamfara State (76%), while Hyalomma dromedarii was the most prevalent in Sokoto State (44%), confirming the widespread transfer of this species from camels onto livestock and its adaptation to cattle in the region. Of 159 ticks screened, 2 out of 54 (3.7%) from Zamfara State and 29 out of 105 (27.6%) from Sokoto State harboured DNA of Theileria annulata, the agent of tropical theileriosis.ConclusionsThis study confirms the presence of a broad diversity of tick species in cattle from north-western Nigeria, providing the first locality records for Zamfara State. The occurrence of H. turanicum indicates a distribution of this tick beyond northern Africa. This study provides the first report for T. annulata in Nigerian ticks. Given its enormous burden on livestock farming in north Africa and across Asia, further investigations are needed to better understand its epidemiology, vector transmission and potential clinical significance in cattle from northern Nigeria and neighbouring Sahelian countries.Graphical abstract

Cattle ticks and associated tick-borne pathogens in Burkina Faso and Benin: Apparent northern spread of Rhipicephalus microplus in Benin and first evidence of Theileria velifera and Theileria annulata

Babesiosis, theileriosis, anaplasmosis, and heartwater are tick-borne diseases that threaten livestock production in sub-Saharan Africa including Burkina Faso and Benin. For over a decade, these two bordering countries have been facing an invasion of the livestock by the tick Rhipicephalus microplus, a major vector for babesiosis, accidentally introduced in Benin in 2004. The molecular identification of tick-borne pathogens in this border area is of particular interest due to animals seasonal migration between the two countries. In this survey, epidemiological features of ticks and tick-borne pathogens in cattle were investigated to compare the eastern Burkina Faso, corresponding to a seasonal migration departure zone, and the northern Benin, which represents a seasonal migration arrival zone. Ticks and peripheral blood were collected from a total of 946 cattle in the two areas. Ticks were morphologically identified and the DNA samples from bovine blood and ticks were analysed by Reverse Line Blot (RLB) hybridization process. A total of 2856 ticks were collected on 490 cattle in Burkina Faso, eight tick species were identified, while 3583 ticks were collected on 456 cattle in North Benin with nine tick species identified. The invasive tick, R. microplus was not found in eastern Burkina Faso, but its spread farthest north in Benin is reported. Six tick-borne pathogen species were found in cattle blood both in eastern Burkina Faso and in northern Benin. Ranked in decreasing order of overall prevalences, they are: Theileria mutans (91.1%), Theileria velifera (77.8%), Babesia bigemina (10.9%), Anaplasma marginale (4.2%), Babesia bovis (3.3%), and Theileria annulata (1.8%). To the best of our knowledge, this survey represents the first report of T. velifera and T. annulata in the region. Overall, the TBP prevalences were significantly higher in northern Benin than in eastern Burkina Faso, indicating a higher parasitological risk in this area.

High-Throughput Microfluidic Real-Time PCR for the Detection of Multiple Microorganisms in Ixodid Cattle Ticks in Northeast Algeria.

Ixodid ticks are hematophagous arthropods considered to be prominent ectoparasite vectors that have a negative impact on cattle, either through direct injury or via the transmission of several pathogens. In this study, we investigated the molecular infection rates of numerous tick-borne pathogens in ticks sampled on cattle from the Kabylia region, northeastern Algeria, using a high-throughput microfluidic real-time PCR system. A total of 235 ticks belonging to seven species of the genera Rhipicephalus, Hyalomma, and Ixodes were sampled on cattle and then screened for the presence of 36 different species of bacteria and protozoans. The most prevalent tick-borne microorganisms were Rickettsia spp. at 79.1%, followed by Francisella-like endosymbionts (62.9%), Theileria spp. (17.8%), Anaplasma spp. (14.4%), Bartonella spp. (6.8%), Borrelia spp. (6.8%), and Babesia spp. (2.5%). Among the 80.4% of ticks bearing microorganisms, 20%, 36.6%, 21.7%, and 2.1% were positive for one, two, three, and four different microorganisms, respectively. Rickettsia aeschlimannii was detected in Hyalomma marginatum, Hyalomma detritum, and Rhipicephalus bursa ticks. Rickettsia massiliae was found in Rhipicephalus sanguineus, and Rickettsia monacensis and Rickettsia helvetica were detected in Ixodes ricinus. Anaplasma marginale was found in all identified tick genera, but Anaplasma centrale was detected exclusively in Rhipicephalus spp. ticks. The DNA of Borrelia spp. and Bartonella spp. was identified in several tick species. Theileria orientalis was found in R. bursa, R. sanguineus, H. detritum, H. marginatum, and I. ricinus and Babesia bigemina was found in Rhipicephalus annulatus and R. sanguineus. Our study highlights the importance of tick-borne pathogens in cattle in Algeria.

Anaplasma and Theileria Pathogens in Cattle of Lambwe Valley, Kenya: A Case for Pro-Active Surveillance in the Wildlife-Livestock Interface.

Tick-borne pathogens (TBPs) are major constraints to livestock production and a threat to public health in Africa. This cross-sectional study investigated the risk of infection with TBPs in cattle of Lambwe Valley, Kenya. Blood samples of 680 zebu cattle from 95 herds in six geospatial clusters within 5 km of Ruma National Park were screened for bacterial and protozoan TBPs by high-resolution melting analysis and sequencing of PCR products. We detected Anaplasma bovis (17.4%), Anaplasma platys (16.9%), Anaplasma marginale (0.6%), Theileria velifera (40%), and Theileria mutans (25.7%), as well as an Anaplasma sp. (11.6%) that matched recently reported Anaplasma sp. sequences from Ethiopia. Babesia, Rickettsia, and Ehrlichia spp. were not detected. The animal and herd-level prevalences for TBPs were 78.5% (95% confidence intervals (CI): 75.3, 81.5) and 95.8% (95% CI: 91.8, 99.8), respectively. About 31.6% of cattle were co-infected with 13 combinations of TBPs. The prevalence of TBPs differed between clusters and age, but the risk of infection was not associated with sex, herd size, or the distance of homesteads from Ruma. This study adds insight into the epidemiology of TBPs around Ruma and highlights the need for proactive surveillance of TBPs in livestock–wildlife interfaces.

Molecular identification and characterization of Rickettsia spp. and other tick-borne pathogens in cattle and their ticks from Huambo, Angola

Ticks are one of the most common vectors of a broad variety of pathogenic agents that significantly affects cattle production causing reduced productivity and important economic losses, while simultaneously having an impact on human health due to the zoonotic risk. In much of the territory of Angola urban population has grown rapidly in recent decades, sharing today close contact with large farms that are generally owned by city residents, providing the ideal conditions for vector-borne pathogens (VBP) transmission between animals and humans. Here we studied the occurrence of Rickettsia, Anaplasma, Ehrlichia, Babesia and Theileria in domestic cattle (n = 98) from Huambo, Angola, and their ticks (n = 116) to obtain a more detailed knowledge into the spectrum of tick-borne agents circulating in this population. We morphologically identified Amblyomma variegatum, Rhipicephalus decoloratus and R. evertsi mimeticus ticks, further confirmed by molecular analysis of the 12S rDNA and 16S rDNA genes. Although none of the bovine blood showed to be positive for R. africae by the ompB, ompA and gltA assays, five ticks showed to be positive for R. africae by the ompB, ompA and the gltA PCRs. Two 18S rRNA sequences were retrieved from bovine blood and one sequence from A. variegatum tick, showing 100% identity with Theileria mutans. By using a PCR targeting the 16S rRNA gene of Anaplama spp. we have also obtained six bovine blood samples showing 99–100 % nucleotide sequence identity with A. capra, two showing 98 % nucleotide sequence identity with A. phagocytophilum and three showing 98–100 % nucleotide sequence identity with A. platys. None of the ticks were positive.The present study shows the presence of a wide range of vector-borne diseases in domestic cattle and their ticks in Huambo province, Angola. Given the lack of both animal and human health infrastructures in this rural region, swift diagnosis and treatment is hampered which could produce a more severe impact on health.

Molecular detection and characterization of tick-borne haemoparasites among cattle on Zanzibar Island, Tanzania

Tick-borne diseases (TBDs) are serious constraints to livestock production in Tanzania and other tropical and subtropical countries and impact the livelihoods of resource-poor farming communities in the region. In Tanzania, detailed studies on tick-borne pathogens (TBPs) in cattle using sensitive molecular detection methods are scarce. The objective of this study was to investigate the occurrence and species composition of bovine TBPs in cattle kept in Zanzibar Island. A total of 236 blood samples were randomly collected in cattle population in June and July 2019. We used polymerase chain reaction (PCR) and gene sequencing to detect and identify pathogens. PCR screening of all 236 samples revealed that 64.5% of animals were infected by TBPs, including Theileria parva (34.3%), T. mutans (38.1%), T. taurotragi (30.9%), Anaplasma marginale (10.2%), Babesia bigemina (5.1%), T. velifera (3.4%) and B. bovis (2.1%). Overall a total of 86 animals (36.4%) were co-infected with up to five pathogens including T. parva, T. mutans, T. taurotragi, A. marginale and B. bigemina. The pathogens mostly involved in the co-infection were T. parva, T. taurotragi and T. mutans. Sequence analysis indicated that T. parva p104 and B. bigemina RAP1a genes are diverse among the sampled animals in Zanzibar Island, with 99.64%–100% and 99.51%–100% nucleotide sequence identity value respectively. In contrast, the A. marginale MSP-5, T. mutans 18S rRNA V4 region and B. bovis SBP-2 genes are conserved, with 100%, 99.05%-100% and 99.66%-100% nucleotide sequence identity values respectively. The phylogenetic analyses revealed that T. parva p104 and B. bigemina RAP1a gene sequences showed significant differences of genotypes, as they appear in different clades. Meanwhile, A. marginale MSP-5, T. mutans 18S rRNA V4 region and B. bovis SBP-2 gene sequences appear in the same clade with other sequences extracted from the NCBI GenBank. The epidemiological findings revealed in this study will provide important information on tick-borne diseases in Tanzania and will be used as scientific basis for planning future control strategies.

Molecular Detection, Phylogenetic Analysis, and Genetic Diversity of Theileria annulata, Babesia bigemina, and Anaplasma marginale in Cattle in Three Districts of Egypt

Under the poor hygienic conditions, tick-borne pathogens cause severe economic losses to the cattle industry. The current study investigated the presence of Theileria annulata, Babesia bigemina, and Anaplasma marginale, the most relevant tick-borne pathogens in cattle, in 3 provinces of Egypt utilizing species-specific PCR assays. PCR was conducted, on bovine blood specimens, using primers targeting the T. annulata merozoite-piroplasm surface antigen (Tams1, 768bp), A. marginale major surface protein-1b gene (msp1b, 265bp), and B. bigemina small subunit ribosomal RNA gene (SSrRNA, 543bp). PCR findings revealed overall prevalences of T. annulata, B. bigemina, and A. marginale as 22.0% (33/150), 19.33% (29/150), and 10.6% (16/150), respectively. The co-infection with two or three pathogens was detected in 20.0% (30/150) of examined specimens. Sequence analyses indicated that T. annulata and A. marginale varied from those of corresponding GenBank sequences revealing percent identities ranging from 90.68 to 97.75% and from 94.98 to 98.63%, respectively. On the other hand, the obtained B. bigemina sequences showed a high similarity with those previously reported in GenBank with a percent identity ranging from 98.85 to 100%. T. annulata was the most prevalent tick-borne pathogen in examined bovine specimens. The genetic diversity of markers used for identification of T. annulata and A. marginale should be highly considered.

Molecular identification of Ehrlichia sp. in a beef cattle from brazilian Cerrado - case report

ABSTRACT Ehrlichia infections in cattle are frequent in Africa but have also been reported in Brazil and North America. This paper reports natural infection by Ehrlichia sp. associated with Babesia bigemina and Anaplasma marginale in a calf in the municipality of Campo Grande, state of Mato Grosso do Sul, Brazil, presenting polioencephalomalacia. The molecular evidence, based on a fragment of the dsb gene, indicates a species of Ehrlichia genetically related to Ehrlichia canis and other species of the genus found in the tick Rhipicephalus (Boophilus) microplus and a calf from Brazil (99 to 100% identity). It was not possible to associate the clinical signs with Ehrlichia infection due to co-infections and histological evidence of another disease. However, the circulation of the bacteria in bovines in Brazilian Cerrado was confirmed and more attention should be given to clinical suspicion of tick-borne pathogens in cattle to clarify the pathogenic potential of Ehrlichia sp.

Molecular identification and prevalence of tick-borne pathogens in zebu and taurine cattle in North Cameroon

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

Molecular detection and characterization of tick-borne protozoan and rickettsial pathogens isolated from cattle on Pemba Island, Tanzania

Tick-borne diseases cause significant losses to livestock production in tropical and subtropical regions. In Tanzania, detailed studies on tick-borne pathogens in cattle using sensitive molecular detection methods are scarce. In this study, we investigated the occurrence of Theileria spp., Babesia spp., Anaplasma spp. and Ehrlichia spp. in 245 blood samples collected from cattle on Pemba Island, Tanzania. We used polymerase chain reaction (PCR) and gene sequencing to detect and identify pathogens. PCR screening revealed overall infection rates of 62.4% for Theileria spp., 17.6% for Babesia bigemina, 15.9% for Anaplasma marginale, 7.4% for Ehrlichia ruminantium and 4.5% for Babesia bovis. Further analysis using sequences of Theileria spp. 18S rRNA revealed infection of cattle with Theileria mutans (68.6%), Theileria taurotragi (48.4%), Theileria parva (41.2%), and Theileria ovis (1.9%). Co-infections of cattle, with up to six tick-borne pathogens, were revealed in 46.9% of the samples. Sequence analysis indicated that T. parva p104, E. ruminantium pCS20 and A. marginale MSP-5 genes are conserved among cattle blood samples in Pemba, with 99.3%–100%, 99.6%–100% and 100% sequence identity values, respectively. In contrast, the B. bigemina RAP-1a and B. bovis SBP-2 gene sequences were relatively diverse with 99.5%–99.9% and 66.4%–98.7% sequence identity values respectively. The phylogenetic analyses revealed that T. parva p104, E. ruminantium pCS20 and A. marginale MSP-5 gene sequences clustered in the same clade with other isolates from other countries. In contrast, the B. bigemina RAP-1 and B. bovis SBP-2 gene sequences showed significant differences in the genotypes, as they appeared in separate clades. This study provides important data for understanding the epidemiology of tick-borne diseases, and is expected to improve the approach for diagnosis and control of tick-borne diseases in Tanzania.