First report on molecular surveillance based on duplex detection of Anaplasma marginale and Theileria annulata in dairy cattle from Punjab, Pakistan

High Prevalence and Genetic Heterogeneity of Anaplasma marginale in Smallholder Bovine Populations of Pakistan, and Its Implications

Bovine anaplasmosis, caused by Anaplasma marginale, is a major tick-borne disease in tropical and subtropical regions of the world, leading to significant production losses. Prolonged convalescence periods are common and surviving animals often become subclinical carriers. This study aimed to detect and characterise A. marginale in bovines in smallholder dairy farms across diverse climatic zones of Pakistan using molecular methods. In total, 321 blood DNA samples from apparently healthy cattle (n = 174) and buffaloes (n = 147) from six districts in Pakistan were tested for A. marginale using a nested PCR assay, targeting part of the major surface protein B gene (msp1β) as a genetic marker, followed by agarose gel electrophoresis and selective sequencing of amplicons from test-positive samples. Of the 321 DNA samples tested, 135 (42.1%) were test-positive for A. marginale. Prevalence was significantly higher in cattle (64.4%; 112/174) than in buffaloes (15.6%; 23/147), and female bovines (43.5%; 108/248) were more frequently infected than males (37%; 27/73). Phylogenetic analysis of the msp1β sequence data (n = 42) revealed that A. marginale from Pakistan clustered with those from Brazil, Thailand, South Africa, and the USA. This study represents the first comprehensive investigation of A. marginale from bovines from diverse agroecological zones of Pakistan and will further stimulate population genetic studies of A. marginale and investigations into the economic impact of subclinical infections in bovines in smallholder farming systems.

Molecular surveillance based on anaplasmosis in domestic small ruminants: First report on zoonotic Anaplasma capra and phylogenetic insights from Faisalabad, Pakistan

Anaplasma is an intracellular alphaproteobacteria that infects diverse blood cell types in animal hosts including small ruminants. Epidemiological and risk factors information on zoonotic anaplasmosis with respect to anaplasmosis in sheep and goats are scarce. Therefore, the objective of the current study was to estimate the prevalence, risk factors of anaplasmosis and phylogenetic investigation of A. capra in sheep and goats from Faisalabad district, Pakistan. Briefly, 384 blood samples were randomly collected from sheep and goats of Faisalabad district, Pakistan, during January to May 2022. The samples were processed for the detection of Anaplasma targeting 16S rRNA gene using PCR. The data regarding disease determinants were collected using a predesigned questionnaire. Out of 384 samples, 131 samples were found positive for Anaplasma spp. with a prevalence rate of 34.11%. The results indicated a significantly higher prevalence of anaplasmosis in goats (41.88%) compared to sheep (22.00%). In addition, the chi square indicated that housing type, tick infestation, gender, tick control practices, age, mix farming, and hygiene were significantly associated with the occurrence of disease. The analysis of multivariate logistic regression expressed gender as the significant risk factor (p = 0.0001, OR = 1.757, CI = 1.305-2.366). The acquired sequences revealed four novel isolates of A. capra (Genbank accession numbers ON834323, ON838209, ON838210, and ON838211). The phylogenetic analysis of the 16S rRNA gene of A. capra revealed three distinct clusters with 99-100% homology with other isolates from different countries. Our isolates showed higher similarity with isolates from China (KM206273, KP314237, MT799937), Pakistan (ON238129, ON238130, ON238131), Angola (MT898988), India (MZ558066), Iran (MW692362), and Turkey (MT632469) isolated from human, sheep, ticks, goats, cattle, Gaddi goat, Persian Onager (Equus hemionus onager), and Turkish goats, respectively. In conclusion, A. capra is endemic in Punjab, Pakistan, there is a need to conduct large scale surveillance studies to assess the status of this pathogen at human-animal interface as well as to develop effective preventive and control strategies to reduce the economic losses associated with anaplasmosis in small ruminants.

Phenotypic and genotypic characterization of ticks and tick-borne pathogens from cattle in selected villages of Greater Letaba Municipality in Limpopo Province, South Africa

Ticks are blood ectoparasites that feed on domestic, wild animals and humans. They spread a variety of infections such as protozoa, viruses, and bacteria. Moreover, cattle reared by smallholder farmers are susceptible to ticks and tick-borne pathogens. Therefore, accurate identification of ticks and detection of tick-borne pathogens is crucial. The main aim of this study was to identify and characterize ticks and tick-borne pathogens from selected villages in Greater Letaba Municipality, Limpopo Province, using morphological and molecular techniques. A total of 233 ticks were collected from cattle and identified morphologically using appropriate morphological keys. The following tick species were identified: Amblyomma hebraeum, Hyalomma rufipes, Hyalomma truncatum, Rhipicephalus appendiculatus, Rhipicephalus (Boophilus) decoloratus, Rhipicephalus (Boophilus) microplus, Rhipicephalus evertsi evertsi, and Rhipicephalus sanguineus. Rhipicephalus spp. was the most common species accounting to 73.8% of the identified ticks. The genomic DNA was extracted from the whole tick for tick identification and from midguts of the ticks for the detection of tick-borne pathogens, followed by amplification and sequencing. A total of 27 samples were positive for tick-borne pathogens: 23 samples tested positive for Theileria and four samples tested positive for Ehrlichia. Anaplasma and Rickettsial OmpB could not be detected from any of the samples. There was no obvious grouping of ticks and tick-borne pathogens on the bases of their locality. The findings of this study confirm previous reports that indicated that cattle reared by smallholder farmers harbor various ticks and tick-borne pathogens of veterinary, public health, and economic importance. Regular monitoring of tick infestations in villages around the study areas is recommended to avoid disease outbreaks.

Genotyping of ticks: first molecular report of Hyalomma asiaticum and molecular detection of tick-borne bacteria in ticks and blood from Khyber Pakhtunkhwa, Pakistan

Multiple ticks (Acari: Ixodoidea) carrying Rickettsiales bacteria have significant importance for both human and animal health. Thus, the purpose of this work was to genetically analyze tick species and their associated Rickettsiales bacteria in animal hosts. In order to achieve these objectives, various animals (including camels, cattle, goats, sheep, dogs, and mice) were inspected in four districts (Mardan, Peshawar, Kohat, and Karak) of Khyber Pakhtunkhwa to collect ticks, while blood samples were collected from all the symptomatic and asymptomatic cattle in all four districts. A total of 234 ticks were obtained from 86 out of 143 (60.14%) host animals, which were morphologically identified as Rhipicephalus turanicus, Rhipicephalus microplus, Haemaphysalis cornupunctata, and Hyalomma asiaticum. Among these, their representative ticks (126/234, 53.85%) were processed for molecular confirmation using cytochrome c oxidase (cox1) gene. Obtained cox1 sequences of four different tick species showed 99.72%-100% maximum identity with their corresponding species reported from Pakistan, China, India, and Kazakhstan and clustered phylogenetically. This study presented the first genetic report of Hy. asiaticum ticks in Pakistan. Moreover, genetically confirmed tick species were molecularly analyzed by PCR for detection of Rickettsiales DNA using partial fragments of 16S rDNA, 190-kDa outer membrane protein A (ompA), and 120-kDa outer membrane protein B (ompB) genes. In addition, blood samples were analyzed to identify Rickettsiales bacteria using the aforementioned genes. Rickettsiales bacteria were found in 24/126 (19.05%) ticks and 4/16 (25.00%) in symptomatic cattle's blood. The obtained ompA and ompB sequences from Hy. asiaticum ticks showed 99.73%-99.87% with Candidatus Rickettsia shennongii and unidentified Rickettsia sp., whereas the obtained 16S rDNA sequences from cattle's blood and ticks (Hae. cornupunctata) showed 99.67% highest identity with Anaplasma phagocytophilum. The 16S rDNA sequence of Rickettsiales DNA from Rh. turanicus ticks showed 100% identity with Ehrlichia canis and unidentified Ehrlichia sp. Obtained sequences of Rickettsiales bacteria were grouped along with their respective species in phylogenetic trees, which were previously reported in Greece, Cuba, Iraq, Turkey, Pakistan, South Korea, and China (mainland and Taiwan). This extensive study explores the wide range of damaging ticks and their corresponding tick-borne bacteria in the area, suggesting a possible danger to both livestock and human communities.

Leading report of molecular prevalence of tick borne Anaplasma marginale and Theileria ovis in yaks (Bos grunniens) from Pakistan

Domestic yak (Bos grunniens) is an economically important feature of the mountainous region of Gilgit-Baltistan in Pakistan where agriculture is restricted and yaks play multiple roles which includes being a source of milk, meat, hides, fuel and power. However little is known about the parasitic infections in Pakistani yaks. Aim of this research was to report the prevalence and genetic diversity of protozoa parasite (Theileria ovis, 18 S rDNA gene was targeted) and an obligate bacterium (Anaplasma marginale, msp-1 gene was amplified) in the blood that was sampled from 202 yaks collected from four districts in Gilgit-Baltistan during January 2023 till January 2024. Results revealed that 6/202 (3%) yaks were of Theileria ovis while 8/202 (4%) were Anaplasma marginale infected. Positive PCR products of both parasites were confirmed by DNA sequencing and their similarity with previously available pathogen sequences was determined by BLAST analysis. Phylogenetic tree indicated that isolates of both parasites displayed genetic. Anaplasma marginale infection varied with the sampling districts and Shigar district had the highest rate of bacterial infection. Cows were significantly more prone to Theileria ovis infection than bulls. Calf and hybrid yaks were more prone to Anaplasma marginale infection. In conclusion, this is the first report that yaks residing the Gilgit-Baltistan region in Pakistan are infected with Theileria ovis and Anaplasma marginale. Similar larger scales studies are recommended in various regions of Gilgit-Baltistan to document the infection rates of these parasites to formulate strategies that will lead to the effective control of these pathogens.

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.

Simultaneous molecular detection of Anaplasma marginale and Theileria annulata in cattle blood samples collected from Pakistan-Afghanistan boarder region

Theileria annulata (T. annulata) and Anaplasma marginale (A. marginale) are among the most extensively reported tick borne pathogens and are associated with huge economic losses worldwide. A total of 298 cattle blood samples were screened to report the presence of these two pathogens. The samples were collected from apparently healthy cattle (Achai, n = 155, Jersy, n = 88 and crossbred, n = 55) in Bajaur district of Khyber Pakhtunkhwa (KPK) during June and July of 2022. A total of 31 out of 298 cattle (10.4%) were found infected with T. annulata as PCR amplified a 156 base pair fragment from Tams-1 gene of T. annulata from their blood. While 16/298 animals (5.4%) were found infected with A. marginale as they amplified a 382 base pair fragment specific for msp5 gene of this bacterium. Three animals (1%) were found co infected. Cattle susceptibility to T. annulata infection was significantly higher than A. marginale infection (P < 0.001). Phylogenetic analysis revealed that Pakistani isolates of both detected pathogen clustered together and were closely related isolates from worldwide countries. Prevalence of T. annulata varied significantly among the sampling sites (P = 0.05) while no such association was observed for A. marginale among the tested cattle. Epidemiological data analysis revealed that none of the studied risk factors was found associated either with the prevalence of T. annulata or A. marginale (P > 0.05) among enrolled cattle. In conclusion, our study has revealed a relatively higher prevalence of T. annulata than A. marginale in cattle from the Bajaur district in KPK. This information is important for improving the productivity of the livestock sector, which is one of the main sources of income in the country. It is recommended that this data be taken into account for the development and implementation of effective tick control programs, as well as for the improvement of livestock management practices to prevent and manage TBDs in Pakistan.

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%).