Epidemiology and molecular detection of Anaplasma spp. in goats from Chattogram district, Bangladesh

First molecular survey of tick-borne protozoan and bacterial pathogens in the questing tick population in Bangladesh

Questing ticks carry various tick-borne pathogens (TBPs) that are responsible for causing tick-borne diseases (TBDs) in humans and animals around the globe, especially in the tropics and sub-tropics. Information on the distribution of ticks and TBPs in a specific geography is crucial for the formulation of mitigation measures against TBDs. Therefore, this study aimed to survey the TBPs in the questing tick population in Bangladesh. A total of 2748 questing hard ticks were collected from the pastures in Sylhet, Bandarban, Sirajganj, Dhaka, and Mymensingh districts through the flagging method. After morphological identification, the ticks were grouped into 142 pools based on their species, sexes, life stages, and collection sites. The genomic DNA extracted from tick specimens was screened for 14 pathogens, namely Babesia bigemina (AMA-1), Babesia bovis (RAP-1), Babesia naoakii (AMA-1), Babesia ovis (18S rRNA), Theileria luwenshuni (18S rRNA), Theileria annulata (Tams-1), Theileria orientalis (MPSP), Anaplasma marginale (groEL), Anaplasma phagocytophilum (16S rRNA), Anaplasma bovis (16S rRNA), Anaplasma platys (16S rRNA), Ehrlichia spp. (16S rRNA), Rickettsia spp. (gltA), and Borrelia (Bo.) spp. (flagellin B) using genus and species-specific polymerase chain reaction (PCR) assays. The prevalence of the detected pathogens was calculated using the maximum likelihood method (MLE) with 95 % confidence interval (CI). Among 2748 ixodid ticks, 2332 (84.86 %) and 416 (15.14 %) were identified as Haemaphysalis bispinosa and Rhipicephalus microplus, respectively. Haemaphysalis bispinosa was found to carry all the seven detected pathogens, while larvae of R. microplus were found to carry only Bo. theileri. Among the TBPs, the highest detection rate was observed in A. bovis (20/142 pools, 0.81 %, CI: 0.51-1.20), followed by T. orientalis (19/142 pools, 0.72 %, CI: 0.44-1.09), T. luwenshuni (9/142 pools, 0.34 %, CI: 0.16-0.62), B. ovis (4/142 pools, 0.15 %, CI: 0.05 - 0.34) and Bo. theileri (4/142 pools, 0.15 %, CI: 0.05-0.34), Ehrlichia ewingii (3/142 pools, 0.11 %, CI: 0.03-0.29), and Babesia bigemina (1/142, 0.04 %, CI: 0.00 - 0.16). This study reports the existence of T. luwenshuni, E. ewingii, and Bo. theileri in Bangladesh for the first time. The novel findings of this study are the foremost documentation of transovarian transmission of B. bigemina and E. ewingii in H. bispinosa and also provide primary molecular evidence on the presence of E. ewingii and Bo. theileri in H. bispinosa. Therefore, this study may shed light on the circulating TBPs in ticks in the natural environment and thereby advocate awareness among physicians and veterinarians to control and prevent TBDs in Bangladesh.

Molecular and haematological investigations on Anaplasma ovis infection in goats in Ahvaz, Iran: Insights into infection rate, haemolytic effect and breed influences

BACKGROUND

Anaplasma ovis (A. ovis) is the predominant causative agent of anaplasmosis in goats and sheep in most tropical and subtropical regions of the world. However, there is considerable variation in reported infection rates, breed susceptibility, and controversial findings regarding the haemolytic effects of A. ovis infection in goats.

OBJECTIVES

Thus, we investigated the molecular and haematological aspects of A. ovis infection in goats from Ahvaz city.

METHODS

One hundred and fifty apparently healthy goats (74 blacks and 76 Najdi goats) were randomly sampled from six flocks in the Ahvaz suburb during ticks' activity season. Haematological evaluation, smear microscopic (SM) examination and PCR assay were performed to assess A. ovis infection. Additionally, the percentage of parasitemia was determined from blood smears.

RESULTS

SM examination revealed that 25.7% of the goats displayed erythrocyte Anaplasma-like inclusion bodies. PCR analysis indicated that 54% of the goats were positive for A. ovis infection (44.6% of blacks and 63.2% of Najdi goats). No significant difference in haematological values was observed between healthy and infected goats based on PCR testing. However, a significant difference in haematological indices was observed between the group with parasitemia level of 0.01-0.02% (SM and PCR positive) compared to the healthy goats (SM and PCR negative), particularly concerning Hb, PCV and RBC count (p < 0.01).

CONCLUSIONS

When the parasitemia exceeds 0.01%, A. ovis infection may disrupt haematological parameters in infected goats. The high prevalence of A. ovis infection (54%) among the studied goats underscores the importance of giving special attention to implementing necessary measures for disease control in the Ahvaz suburb.

Molecular characterization and phylogeny of Anaplasma marginale, A. phagocytophilum and A. bovis in livestock of Bangladesh

The emergence of Tick-borne Anaplasma spp. poses a significant threat to humans and animals worldwide. Traditional surveys based on examining blood smears overlook the existence of emerging pathogens. This study aimed to screen Anaplasma spp. in livestock species from diverse geographies with molecular tools. We collected 276 blood samples from cattle (Bos indicus), gayals (Bos frontalis) and goats (Capra hircus) in Jhenaidah, Bogura, Sirajganj and Bandarban districts, and Naikhongchari sub-district from June 2021 to March 2022. After that, a molecular screening was conducted through polymerase chain reaction (PCR) and sequencing was done to confirm the PCR results. The PCR assays were performed based on the analyses of groEL (Anaplasma marginale) and 16S rRNA (A. phagocytophilum and A. bovis). The Anaplasma spp. detected in this study were A. marginale (10.51%), A. phagocytophilum (0.72%), and A. bovis (63.77%). However, A. platys was not detected in this study. Among the screened pathogens, the detection of A. bovis (82.86%) was significantly high in the Bandarban district, while A. marginale was found only in cattle in this location. Regarding animal species, the occurrence of A. bovis was significantly higher in cattle. Moreover, the detection rate of A. marginale was significantly higher in adult cattle (≥2 years). The phylogenetic analyses revealed that the groEL sequences of A. marginale and 16S rRNA sequences of A. bovis and A. phagocytophilum were included in a single clade in the respective phylograms, showing a single genotype of each species circulating in Bangladesh. This study reports the existence of A. phagocytophilum in Bangladesh for the first time.

Molecular prevalence and phylogeny of Anaplasma marginale, Anaplasma ovis and Theileria ovis in goats and sheep enrolled from a hill station in Punjab, Pakistan

Anaplasma marginale (A. marginale), Anaplasma ovis (A. ovis) and Theileria ovis (T. ovis) are among the most commonly reported intracellular tick borne pathogens that infect ruminants across the globe causing huge economic losses. This study aims to report the prevalence and phylogenetic evaluation of these three pathogens infecting sheep and goats (n = 333) that were enrolled from Fort Munro region in Pakistan by using msp1b, msp4 and 18S rRNA genes for A. marginale, A. ovis and T. ovis respectively. Results revealed almost similar infection rates in sheep and goats with an overall prevalence of 11% for A. marginale, 28% for A. ovis and 3% for T. ovis. Concurrent infection was also recorded, however, the number of animals infected with two pathogens (n = 24; 7.2%) was higher than infection with three pathogens (n = 2; 0.6%). Risk factor analysis revealed that sheep reared in small herds had higher A. marginale (P = 0.03) and A. ovis (P = 0.04) infection rates compared to those from large herds. In addition, it was observed that bucks (P ≤ 0.05) and tick-free goats (P ≤ 0.05) exhibited higher A. ovis infection rates than nannies. Phylogenetic analysis of all three pathogens showed that Pakistani isolates were clustered together and were closely related to previously deposited Pakistani isolates as well as with those that were reported from worldwide countries. In conclusion, we are reporting that Pakistani sheep and goats have A. marginale, A. ovis and T. ovis mediated infections and control measures should be taken against them to improve the productivity of the livestock sector.

Epidemiology and Phylogeny of Anaplasma ovis with a Note on Hematological and Biochemical Changes in Asymptomatic Goats Enrolled from Four Districts in Punjab, Pakistan

Background: Anaplasma ovis is an intra-erythrocytic gram negative rickettsial bacterium that infects small ruminants, resulting in huge economic losses worldwide. Materials and Methods: The present investigation aims at reporting the molecular prevalence of A. ovis in 1200 asymptomatic goats that were enrolled from 4 districts (Layyah, Lohdran, Dera Ghazi Khan, and Rajanpur) in Punjab, Pakistan by targeting the msp4 gene of bacterium. Risk factors associated with the prevalence of A. ovis and phylogeny of bacterium were also documented. Results: 184 out of 1200 (15%) goat blood samples were infected with A. ovis. The prevalence of the pathogen varied with the sampling sites (p = 0.005), and the highest prevalence was detected in goats from Layyah (19%) followed by Rajanpur (17%), Dera Ghazi Khan (15%), and Lohdran district (9%). The represented partial msp4 gene amplicon was confirmed by Sanger sequencing and deposited to GenBank (OP225957-59). Phylogenetic analysis revealed that the amplified isolates resembled the msp4 sequences reported from Iran, Mangolia, Sudan, and the United States. Sex and age of goats, herd composition and size, and the presence of ticks on goats and dogs associated with herds were the rick factors associated with the prevalence of A. ovis. Red blood cells, lymphocytes (%), neutrophils (%), hemoglobin, and hematocrit levels in blood and Aspartate amino transferase, urea, and creatinine levels in serum were disturbed in A. ovis infected goats when compared with uninfected animals. Conclusion: We are reporting the prevalence of A. ovis in Pakistani goats from four districts of Punjab and these data will help in developing the integrated control policies against this tick-borne pathogen that is infecting our goat breeds.

Molecular Epidemiology, Seasonality and Phylogenetic Investigations of Anaplasma ovis in Small Ruminants from Diverse Agro-Climatic Regions of Punjab, Pakistan

Anaplasma (A.) ovis is the most important cause of anaplasmosis in small ruminants. The current study was planned to estimate the molecular prevalence, risk factors, and phylogenetic analysis of A. ovis infection in sheep and goats from different agro-climatic regions of Central and Southern Punjab, Pakistan. A total of 400 jugular blood samples were collected from asymptomatic goats (n = 200) and sheep (n = 200) from the Jhang and Dera Ghazi Khan districts from January 2021 to February, 2023. Two hundred blood samples were collected from each district. Ten union councils (UC) were randomly chosen from each district, and 20 samples were collected from each UC based on the multistage cluster sampling technique. The samples were analyzed with PCR targeting the major surface protein (msp4) gene of A. ovis. The overall molecular prevalence of anaplasmosis was 57.5%. The disease occurrence was higher in Dera Ghazi Khan (61.5%) than in the Jhang district (53.5%). Infection positivity was greater in goats (65.5%) than in sheep (49.5%). Multivariate logistic regression analysis indicated that host species [sheep; Odds Ratio (OR) = 3.212; p = 0.000, Confidence Interval (CI) = 1.968-5.242], age (adult; OR = 2.606; p = 0.003, CI = 1.398-4.858), and acaricide use (never; OR = 13.671; p = 0.000, CI = 6.414-26.283) were significantly higher risk for A. ovis in small ruminants (p< 0.05; OR > 1). The sequencing and phylogenetic analysis of four representative isolates in the current study (Genbank numbers; Goats: OQ302202, OQ302203; Sheep: OQ319592, OQ319593) revealed novel strains of A. ovis with 97-100% similarity from different countries. The msp4-based goat isolates showed greater genetic diversity, while sheep genotypes showed homology with isolates from Italy, Spain, Hungary, Cyprus, Spain, Iran, and China. The current surveillance study will help in devising prevention and control strategies regarding anaplasmosis in small ruminants. However, there is a need for further study on the clinicopathological and vector competence aspects of these genotypes.

Molecular Epidemiological Investigation of Piroplasms and Anaplasmataceae Bacteria in Egyptian Domestic Animals and Associated Ticks

Piroplasmosis and anaplasmosis are serious tick-borne diseases (TBDs) that are concerning for the public and animal health. This study aimed to detect the molecular prevalence and epidemiological risk factors of Piroplasma and Anaplasma species in animal hosts and their associated ticks in Egypt. A total of 234 blood samples and 95 adult ticks were collected from animal hosts (112 cattle, 38 sheep, 28 goats, 26 buffaloes, 22 donkeys, and 8 horses) from six provinces of Egypt (AL-Faiyum, AL-Giza, Beni-Suef, Al-Minufia, Al-Beheira, and Matruh). Blood and tick samples were investigated by polymerase chain reaction coupled with sequencing targeting 18S and 16S RNA genes for Piroplasma and anaplasmataceae, respectively. Statistical analysis was conducted on the potential epidemiological factors. Of the 234 animals examined, 54 (23.08%) were positive for pathogens DNA distributed among the six provinces, where 10 (4.27%) were positive for Piroplasma, 44 (18.80%) for anaplasmataceae, and 5 (2.14%) were co-infected. Co-infections were observed only in cattle as Theileria annulata and Anaplasma marginale plus Babesia bigemina, A. marginale plus B. bigemina, and T. annulata plus B. bigemina. Piroplasmosis was recorded in cattle, with significant differences between their prevalence in their tick infestation factors. Animal species, age, and tick infestation were the potential risk factors for anaplasmosis. All ticks were free from piroplasms, but they revealed high prevalence rates of 72.63% (69/95) with anaplasmataceae. We identified T. annulata, B. bigemina, and A. marginale in cattle; A. platys in buffaloes; A. marginale and A. ovis in sheep; for the first time, A. ovis in goats; and Ehrlichia sp. in Rhipicephalus annulatus ticks. Our findings confirm the significant prevalence of piroplasmosis and anaplasmosis among subclinical and carrier animals in Egypt, highlighting the importance of the government developing policies to improve animal and public health security.

First Molecular Identification of Babesia, Theileria, and Anaplasma in Goats from the Philippines

Goats are key livestock animals and goat raising is an income-generating venture for smallholder farmers, supporting agricultural development in many parts of the world. However, goat production is often limited by various factors, such as tick-borne diseases. Goat piroplasmosis is a disease caused by apicomplexan parasites Babesia spp. and Theileria spp., while anaplasmosis is caused by bacterial Anaplasma spp. In the Philippines, the presence of Babesia, Theileria, and Anaplasma has not been reported in goats. In this study, DNA obtained from goats were molecularly screened for Babesia/Theileria and Anaplasma. Of 396, 77.02% (305/396) and 38.64% (153/396) were positive for piroplasma and Anaplasma using PCR assays targeting the 18S rRNA and 16S rRNA genes, respectively. Similarly, Babesia ovis was detected in six samples (1.52%). Representative Babesia/Theileria sequences shared 89.97–97.74% identity with each other and were most closely related to T. orientalis, T. annulata, and Theileria spp. Meanwhile, Anaplasma 16SrRNA sequences were related to A. odocoilei, A. platys, and A. phagocytophilum. This is the first molecular identification of B. ovis, Theileria spp., and Anaplasma spp. in goats from the Philippines.

Molecular Detection and Genetic Diversity of Tick-Borne Pathogens in Goats from the Southern Part of Thailand

Tick-borne hemoprotozoan and rickettsial diseases affect the health and productivity of small ruminants in tropical and subtropical regions. Despite the large population of goats in the southern part of Thailand, there is limited information on the prevalence of tick-borne pathogens. In this study, polymerase chain reaction was used to detect the presence of Theileria spp., T. ovis, T. orientalis, Babesia ovis, Anaplasma ovis, and A. marginale in 262 goats from three provinces in the southern part of Thailand. In this investigation, Theileria spp. and A. ovis were detected while T. ovis, B. ovis, and A. marginale were not detected. Overall infection rates of Theileria spp. and A. ovis were 10.3% and 1.5%, respectively. The co-infections of two parasites was observed in 1.5% of goats. Sequence analysis showed the presence of T. luwenshuni and T. orientalis in the goat samples. This study is the first to use the molecular detection of T. orientalis in Thai goats, and presents genetic characterization using the major piroplasm surface protein (MPSP) gene. In the phylogenetic analysis, the T. orientalis MPSP sequence was classified as type 7. The A. ovis major surface protein 4 (MSP4) gene sequences shared high identities and similarity with each other and clustered with isolates from other regions. This study provides information about the prevalence and genetic diversity of tick-borne pathogens in goats in the study area, and is expected to be valuable for the development of effective control measures to prevent disease in animals in Thailand.