Existence of genetic lineages within Asian genotype of Taenia solium-Genetic characterization based on mitochondrial and ribosomal DNA markers

Common Methods for Phylogenetic Tree Construction and Their Implementation in R

A phylogenetic tree can reflect the evolutionary relationships between species or gene families, and they play a critical role in modern biological research. In this review, we summarize common methods for constructing phylogenetic trees, including distance methods, maximum parsimony, maximum likelihood, Bayesian inference, and tree-integration methods (supermatrix and supertree). Here we discuss the advantages, shortcomings, and applications of each method and offer relevant codes to construct phylogenetic trees from molecular data using packages and algorithms in R. This review aims to provide comprehensive guidance and reference for researchers seeking to construct phylogenetic trees while also promoting further development and innovation in this field. By offering a clear and concise overview of the different methods available, we hope to enable researchers to select the most appropriate approach for their specific research questions and datasets.

Unveiling genotypic diversity of Theileria orientalis in lethal outbreaks among bovines in Karnataka, India

Theileria orientalis, the causal agent of oriental theileriosis, is known to cause mild disease in cattle and buffalo across the world. Recently, different genotypes of T. orientalis have emerged as pathogenic, causing high reported morbidity in cattle. This study focuses on investigating three suspected outbreaks of oriental theileriosis that resulted in fatalities among crossbred and indigenous bulls in Karnataka, India. Examination of blood smears revealed the presence of T. orientalis piroplasms within erythrocytes. The genetic characterization of T. orientalis was conducted by targeting specific markers, including the mpsp gene, p23 gene, and ribosomal DNA markers (18S rRNA gene, ITS-1, and ITS-2). Analysis based on the 18S rRNA gene unveiled the presence of both Type A and Type E genotypes of T. orientalis in the outbreaks. The mpsp gene-based analysis identified genotype 7 of T. orientalis in crossbred cows, whereas genotype 1 (Chitose B) was found to be present in indigenous bulls. Haplotype network analysis based on the mpsp gene revealed the presence of 39 distinct haplotypes within the 12 defined genotypes of T. orientalis with a high haplotype diversity of 0.9545 ± 0.017. Hematological and biochemical analysis revealed a decrease in calcium, hemoglobin levels, red blood cell counts, and phosphorus. This study constitutes the initial documentation of a clinical outbreak of oriental theileriosis in indigenous bulls with genotype 1 (Chitose 1B). Substantial epidemiological investigations are imperative to gain a comprehensive understanding of the geographical distribution of distinct genotypes and the diverse clinical manifestations of the disease across various hosts.

H, Krovvidi S, Chennuru S. Prevalence of taeniosis in pig farming community in Andhra Pradesh, India

Taeniosis is one of the neglected zoonoses in India. Facts on taeniosis, compared to cysticercosis are scanty in India. Hence, this study is aimed to determine the occurrence of taeniosis in human beings in Andhra Pradesh, India. A total of 1380 stool samples were collected from people associated with pig farming and or had the habit of pork eating in certain districts (n = 7) of Andhra Pradesh. Prevalence of human taeniosis was determined using microscopic examination of stool samples and proglottds. The overall prevalence of taeniosis was found to be 0.79%. Morphology of gravid segments revealed lower number of lateral branches indicating T. solium segments. Age and gender of human were not associated with the occurrence of taeniosis. The low prevalence of taeniosis in human indicates good hygiene and sanitation practices in humans, and awareness about the disease and its transmission. Further studies involving more sensitive techniques on stool and serum samples are warranted.

Sub-lineages of Taenia solium Asian Genotype Recorded in North India

PURPOSE

Porcine cysticercosis is a neglected zoonotic disease of significant veterinary and medical importance owing to its economic impact and public health significance. The present study aimed at genetic characterization of Taenia solium metacestodes in slaughtered pigs of Haryana (North India).

METHODS

A total of 213 (160 and 53 from Chandigarh and Hisar, respectively) slaughtered pigs intended for human consumption were screened for the presence of T. solium metacestodes. The retrieved metacestodes were confirmed molecularly based on the partial amplification of mitochondrial cytochrome c oxidase subunit 1 (CO1) gene. Evolutionary divergence, haplotype and nucleotide diversities and neutrality indices of the retrieved isolates were also assessed.

RESULTS

Out of the 213 pigs, 2 (0.94%) revealed the presence of metacestodes involving 1 pig each from Chandigarh (0.62%) and Hisar (1.9%). The sequences obtained after custom sequencing were submitted to GenBank under the accession numbers LC661682-83. The present study haplotype clustered with haplotypes of Asian origin and showed variation from other haplotypes by 1-23 mutational steps. However, the present study isolates also showed nucleotide polymorphisms (A198T, A199G, A201T, G204A, T206A, C210T, T212G, T213A, T216G/A, T217C, T221C, C524T, G994A) at different positions, which indicated the presence of sub-lineages. Low nucleotide diversity (π = 0.020) and negative value of Tajima's D (- 1.304) observed for the haplotypes under consideration was indicative of purifying selection and recent population expansion.

CONCLUSIONS

Our study confirms the circulation of T. solium Asian genotype (with distinct sub-lineages) in study area and recommends strict control measures to contain the zoonotic disease.