Genetic diversity of Babesia bovis in beef cattle in a large wetland in Brazil

Author(s)

Mendes, Natalia Serra ^{[1, 2]} ; de Souza Ramos, Inalda Angelica ^[1] ; Herrera, Heitor Miraglia ^[3] ; Vilela Campos, Joao Bosco ^[3] ; de Almeida Alves, Joao Victor ^[3] ; de Macedo, Gabriel Carvalho ^[3] ; Machado, Rosangela Zacarias ^[1] ; Andre, Marcos Rogerio ^[1]

Affiliation

^[1] Univ Estadual Paulista, FCAV, UNESP, Lab Immunoparasitol, Dept Vet Pathol, Via Acesso Prof Paulo Donato Castellane S-N, BR-14884900 Jaboticabal, SP - Brazil

^[2] Sao Paulo State Univ, Sch Agr & Veterinarian Sci, UNESP, Agr & Livestock Microbiol Grad Program, Jaboticabal - Brazil

^[3] Univ Catolica Dom Bosco, Campo Grande, MS - Brazil

• Document type: Journal article
• Source: Parasitology Research; v. 118, n. 7, p. 2027-2040, JUL 2019.
• Web of Science Citations: 1

Abstract

Babesia bovis is the etiological agent of bovine babesiosis, a disease transmitted by Rhipicephalus microplus, which affects cattle herds in tropical and subtropical regions of the world, causing significant economic losses due to decreasing meat and milk yield. This study used molecular techniques to determine the occurrence and genetic diversity of B. bovis, based on the genes encoding the spherical body protein (sbp-2) and the merozoite surface antigens (MSAs) genes, in a herd of 400 Nellore (Bos indicus) sampled from beef cattle farms in the Pantanal region, state of Mato Grosso do Sul, Midwestern Brazil. The results of the nested PCR assays based on the sbp-2 gene indicated that 18 (4.5%) calves were positive for B. bovis; out of them, while 77.7% (14/18) were positive for the B. bovis msa-2b fragment, 66.6% (12/18) were positive for the msa-2c fragment. The phylogenetic analysis based on the maximum likelihood method using 14 sequences from msa-2b clones and 13 sequences from msa-2c clones indicated that the sequences detected in this study are clearly distributed in different cladograms. These findings corroborated the diversity analysis of the same sequences, which revealed the presence of 14 and 11 haplotypes of the msa-2b and msa-2c genes, respectively. Furthermore, the entropy analyses of amino acid sequences revealed 78 and 44 high entropy peaks with values ranging from 0.25 to 1.53 and from 0.27 to 1.09 for MSA-2B and MSA-2C, respectively. Therefore, the results indicate a low molecular occurrence of B. bovis in beef cattle sampled in the Brazilian Pantanal. Despite this, a high degree of genetic diversity was found in the analyzed B. bovis population, with possibly different haplotypes coexisting in the same animal and/or in the same studied herd. (AU)

• FAPESP's process: 15/14896-1 - Molecular detection and characterization of agents belonging to Anaplasmataceae e Bartonellaceae family in wild animals and ectoparasites in Brazil
• Grantee: Marcos Rogério André
• Support Opportunities: Regular Research Grants