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Bovine anaplasmosis caused by Anaplasma marginale is an important endemic disease that exerts negative impact on livestock production with huge socioeconomic consequences in most developing countries. Genetic studies have reported the existence of diverse ntSTs of A. marginale with varying pathogenicity in different countries. Continuous studies to obtain accurate information on disease etiologies is desirable for the formulation of cost-effective control measures. To this end, 582 blood samples from cattle were collected from 10 out of the 36 States of Nigeria from April 2021 to March 2022 and analyzed based on the major surface protein 5 (msp5) gene to determine the ntSTs of A. marginale in Nigeria. In all, 38 out of the 582 samples (6.5%) from cattle in the different Agro-ecological Zones (AEZs) of Nigeria were positive. The Nigerian A. marginale nucleotide sequences were 96.7 to 100% identical to sequences from other countries and were placed in distinct clusters with other A. marginale sequences deposited in GenBank. Network analysis revealed three ntSTs (#2, #4 & #8) of A. marginale from Nigeria with a nucleotide sequence type diversity (Hd) of 0.8, nucleotide diversity (Pi) of 0.015 and average number of nucleotide differences (k) of 7.09. Two different amino acid substitution sites were found in Nigerian and worldwide sequences at positions 148 and 160. This is the first nationwide report on the ntST diversity and genetic characterization of A. marginale in cattle in Nigeria based on the msp5 gene. Bovine anaplasmosis is widespread in Nigeria and deserves further attention., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Anaplasma marginale is the rickettsia which causes the bovine anaplasmosis. The distribution of A. marginale is both tropical and subtropical regions of the world. The major surface protein 4 (MSP4) of this parasite was identified as an immunodominant protein. In this study, the full length of DNA encoding A. marginale MSP4 (AmMSP4) was cloned from the parasites. The open reading frame of msp4 coding sequence of Thailand strain is 849 bp. Phylogenetic analysis revealed that the msp4 coding sequence of A. marginale was highly conserved when compared with Anaplasma phagocytophilum. The recombinant plasmid was further transformed into the BL21-CodonPlus (DE3)-RIPL competent cells for over-expression of the recombinant major surface protein 4 of A. marginale (rAmMSP4). Sera from rabbit immunized with rAmMSP4 and from cattle infected with A. marginale were used to study the antigenicity of rAmMSP4 (35 kDa) and AmMSP4 (31 kDa). Both rAmMSP4 and AmMSP4 were recognized by these sera showing that recombinant and native AmMSP4 have conserved epitopes. Localization of Anaplasma parasites by immunofluorescence showed these parasites are distributed on both the membrane and the outside of infected erythrocytes. Regarding antigenicity, recombinant MSP4 could be used for immunodiagnostic purposes and as a possible vaccine candidate against anaplasmosis., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Species of the genus Anaplasma, in the family Anaplasmatacae, are responsible to vector-borne diseases that affecting animals and humans. Feline anaplasmosis is poorly reported in Brazil. This study aimed at investigating the occurrence of Anaplasma spp. in domestic cats from Greater Rio de Janeiro, and evaluating hematological changes associated with this rickettsial infection. Were sampled 216 cats, we performed nested PCR (nPCR) and real-time PCR (qPCR) assays targeting A. platys-16S-rDNA, A. platys-gltA and A. phagocytophilum-msp2 sequences. As evaluated with gltA-qPCR the frequency of cats positive for A. platys was 3.7% (n = 8/216) and by 16S-rDNA nested-PCR it was 0.9% (n = 2/216). No cats were positive to msp2-qPCR to A. phagocytophilum. The sequences of A. platys presented 100% similarity with previously described isolates around the world and Brazil. Two cats that were positive in the gltA-qPCR reactions have platelet inclusions in the microscopic examination. However, no significant (p > 0.05) hematological changes were observed, probably due to low parasite load. This study showed that A. platys occur in domestic cats from Greater Rio de Janeiro. Further studies are needed to more precisely characterize these organisms., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Anaplasma phagocytophilum (A. phagocytophilum) is an obligate intracellular bacterium that causes equine granulocytic anaplasmosis (EGA) disease in equines. This pathogen has zoonotic potential, which makes it very important to be detected and controlled as early as possible. This study was aimed to assess the molecular prevalence, associated risk factors of EGA along with its effects on various hematological parameters. This study revealed an overall 10.67% prevalence in equine. Horses showed highest prevalence followed by mules and donkeys presenting 11.86, 10.53 and 9.43% prevalence, respectively. The samples were confirmed for anaplasmosis through sequencing. The BLAST queries confirmed very high homology of our isolates with Chinese and Japanese isolates of A. phagocytophilum (Accession no's; KX505303, KY242456 and LC002836). The phylogenetic analysis found the study isolates clustered with each other and this cluster closely resembled Chinese isolate of A. bovis (FJ169957), A. phagocytophilum (HQ872464) and A. phagocytophilum (NR_044762) human isolate from northern Minnesota and Wisconsin. The key risk factors identified for occurrence of EGA in equine species on the basis of univariable analysis were sex of animal, housing type, tick infestation, previous tick history and tick control status, type of acaricides used, rearing system and farm hygiene, respectively. The hematological parameters like Hemoglobin (Hb), Total Leukocyte Count (TLC), Total Erythrocytes Count (TEC), and granulocytes were decreased in diseased animals. The mules showed no typical hematological variations which make sense for its nature as carrier of infection to the susceptible species. This is the first molecular evidence of EGA in Pakistan. The disease needs to be handled seriously as it has zoonotic potential. The animals should be properly attended in disease conditions as leukopenia, neutropenia and lymphopenia can aggravate the condition by making the animal prone to secondary infections., (Copyright © 2018 Elsevier B.V. All rights reserved.)