RESUMEN
Bovine anaplasmosis is a tick-borne disease caused by an obligate intercellular Gram-negative bacterium named Anaplasma (A.) marginale. In this study, we report the seasonal prevalence, potentially associated risk factors and phylogeny of A. marginale in cattle of three different breeds from Multan District, Southern Punjab, Pakistan. A total of 1020 blood samples (crossbred, n = 340; Holstein Friesian, n = 340; and Sahiwal breed, n = 340) from apparently healthy cattle were collected on a seasonal basis from March 2020 to April 2021. Based on PCR amplification of the msp5 partial sequence, overall, the A. marginale prevalence rate was estimated at 11.1% (113/1020) of the analyzed cattle samples. According to seasons, the highest prevalence rate was observed in autumn (16.5%), followed by winter (10.6%) and summer (9.8%), and the lowest was recorded in the spring (7.5%). The crossbred and Sahiwal cattle were the most susceptible to A. marginale infection, followed by Holstein Friesian cattle (7.9%). Analysis of epidemiological factors revealed that cattle reared on farms where dairy animals have tick loads, dogs coinhabit with cattle and dogs have tick loads have a higher risk of being infected with A. marginale. In addition, it was observed that white blood cell, lymphocyte (%), monocyte (%), hematocrit, mean corpuscular hemoglobin and mean corpuscular hemoglobin concentrations were significantly disturbed in A. marginale-positive cattle compared with non-infested cattle. Genetic analysis of nucleotide sequences and a phylogenetic study based on msp5 partial sequencing demonstrated that this gene appears to be highly conserved among our isolates and those infecting apparently healthy cattle from geographically diverse worldwide regions. The presented data are crucial for estimating the risk of bovine anaplasmosis in order to develop integrated control policies against bovine anaplasmosis and other tick-borne diseases infecting cattle in the country.
RESUMEN
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.