Genetic diversity and molecular survey of Trypanosoma (Megatrypanum ) theileri in cattle in Brazil’s western Amazon region

Abstract

Trypanosoma (Megatrypanum) theileri is a flagellated protozoan that infects ruminants and it displays high genetic diversity. In this study, we investigated the prevalence rates of this protozoan based on hemoculture and molecular diagnosis. The isolates of T. theileri thus obtained were characterized by molecular markers SSU rDNA and gGAPDH and molecular diagnosis based on Cathepsin L-like gene (PCR-TthCATL). The PCR-TthCATL and hemoculture indicated an overall prevalence rate of 8.13%, and the CATL derived sequence named IB was identified for the first time in cattle in the western Amazon region, as well as IF in Brazil. We also describe a possible new PCR-TthCATL derived sequence in cattle, designated IL.

Molecular identification of Trypanosoma theileri (Laveran, 1902) in cattle from two slaughterhouses in Ecuador and its relation with other haemotropic agents

“…Prevalence values for T. theileri in South America are high, suggesting that this parasite is widely distributed in the cattle production systems in this region. The global prevalence values (15.6%) determined in the present study is congruent with reports from some farms in neighboring countries, including 5.0 and 30.4% in Venezuela and Brazil, respectively (39), 8.1% in Brazil (11), and 38.6 to 50.3% in Colombia (6,9). The high prevalence values for T. theileri in other countries have been related to environmental conditions, host, and parasite factors (9).…”

“…Several genotypes have been identified within these lineages as specific for each host species, such is the case for bovines (IIA, IB, IIB, IC), buffaloes (IA) and deers (IIC) (9,29,46). Genotypes IB, IIB and IC, which have been previously described in Brazil, Venezuela and Colombia (9,11,39) were identified in this study. Genotype IIB was the most prevalent in the samples that were analyzed in this study (6/13), which is also consistent with the most prevalent genotype in South America (9,39).…”

“…In Colombia, a northern neighbor country to Ecuador, the reported prevalence values for T. theileri appear to be higher in cattle (38.6 and 50.9%) than in buffaloes (28.2%) (9,10). Lower prevalence values have been reported by Pacheco et al (11), using a PCR based on Cathepsin L-like gene (PCR-TthCATL) in Brazil, with prevalence values of 42.19% per farm and 12.19% per animal.…”

Trypanosomes of the Trypanosoma theileri Group: Phylogeny and New Potential Vectors

“…The two main lineages of the T. theileri group, TthI and TthII, were previously defined based on analyses of ITS (internal transcribed spacer), and SL (spliced leader) genes [16,52]. Subsequently, several trypanosome strains were placed into TthI or TthII based on 18S rRNA gene phylogenies [17,38,53,54]. Recently, an additional lineage was distinguished based on 18S rRNA gene analysis [6].…”

Genetic diversity of cervid Trypanosoma theileri in Honshu sika deer (Cervus nippon) in Japan

“…Modern molecular technology utilising various genetic markers has demonstrated a close evolutional relationship between T. theileri and Megatrypanum-type trypanosomes in wild ruminants (Rodrigues et al, 2003(Rodrigues et al, , 2006(Rodrigues et al, , 2010a(Rodrigues et al, , 2010bHamilton et al, 2005Hamilton et al, , 2009Gibson et al, 2010;Garcia et al, 2011aGarcia et al, , 2011bGarcia et al, , 2020Martinković et al, 2012;Fisher et al, 2013). In parallel, these studies have highlighted the genetic divergence of T. theileri and related Megatrypanum-type trypanosomes of different host and geographical origins based on multiple genetic markers such as the ribosomal RNA gene (rDNA), the glycosomal glyceraldehyde-3-phosphate dehydrogenase (gGAPDH) gene, the spliced leader RNA (SL) gene and cathepsin L-like cysteine protease (CatL-like) genes (Rodrigues et al, 2006(Rodrigues et al, , 2010a(Rodrigues et al, , 2010bGarcia et al, 2011aGarcia et al, , 2011bGarcia et al, , 2020Martinković et al, 2012;Yokoyama et al, 2015;Pacheco et al, 2018).…”