Genetic and population diversity of Toxocara cati (Schrank, 1788) Brumpt, 1927, on the basis of the internal transcribed spacer (ITS) region.

The present investigation was aimed to study the sequence, phylogenetic and haplotype analyses of Toxocara cati based on the ITS region, along with the genetic diversity, demographic history and population-genetic structure. The maximum likelihood tree based on Kimura 2-parameter model was constructed using the complete ITS region of all the nucleotide sequences (n = 57) of Toxocara spp. and other related ascarid worms available in the GenBank™. It placed all the sequences of T. cati into four major clades designated as T. cati genotypes 1-4 (TcG1-G4). A total of 66 signature nucleotides were identified in the ITS region between genotypes. The median-joining haplotype network displayed a total of 24 haplotypes, with China exhibiting the highest number of haplotypes (h = 20) followed by India (h = 4), and Japan and Russia (h = 1). It indicated a clear distinction between all the four genotypes. The pairwise FST values between all the genotypes indicated huge genetic differentiation (> 0.25) between different T. cati genotypes. Moreover, the gene flow (Nm) between T. cati genotypes was very low. Results of AMOVA revealed higher genetic variation between genotypes (92.82%) as compared to the variation within genotypes (7.18%). The neutrality indices and mismatch distributions for the G1-G4 genotypes, Indian isolates and the overall dataset of T. cati indicated either a constant population size or a slight population increase. The geographical distribution of all the genotypes of T. cati is also reported. This is the first report of genotyping of T. cati on the basis of the ITS region.

Population genetics of Babesia vogeli based on the mitochondrial cytochrome b gene.

The current study aimed at population genetic characterization of B. vogeli based on the cytochrome b (cyt b) gene sequences (≥ 685 bp) available in the GenBank. Phylogenetic trees placed all the sequences of B. vogeli in a single large monophyletic clade; however, it was further divided into two subclades (Bv1 and Bv2). Out of seven nucleotide variations observed between Bv1 and Bv2 subclades, four were synonymous (G92A, C170T, T488C and A659G), and three were non-synonymous (G324A, C438A and G465A) resulting in amino acid substitutions at three places (V108I, L146I and V155I). Within different B. vogeli populations, the nucleotide and haplotype diversities were low. The median-joining haplotype network revealed only two haplotypes (Hap_1 and Hap_2). A geographical sub-structuring was noticed in the B. vogeli populations, with moderate genetic differentiation (FST = 0.05000; P < 0.05) and a very high gene flow (Nm = 4.75) between Indian and Chinese populations. Neutrality tests and mismatch distributions for the Indian population and the overall dataset of B. vogeli indicated a constant population size. This study provides the first insight into the genetic characterization, population genetics and haplotype network of B. vogeli based on the cyt b gene.

Genetic diversity and molecular evolution of the internal transcribed spacer regions (ITS1-5.8S-ITS2) of Babesia vogeli.

Canine babesiosis, a severe haemoparasitic disease caused by Babesia species, has a significant global presence and can be fatal if left untreated. The current study was aimed to perform the population genetic characterization of B. vogeli on the basis of the internal transcribed spacer regions (ITS1-5.8S-ITS2). A maximum likelihood tree constructed with the Hasegawa-Kishino-Yano model grouped all sequences into a single major clade (BvG1), with the exception of a Taiwanese isolate (EF186914), which branched separately. This Taiwanese isolate represented a novel genotype (BvG2) identified in the present study. Nucleotide sequences (n = 62) exhibited 92.5-100 % nucleotide identity among themselves. However, the BvG1 and BvG2 genotypes shared a lower identity of 92.5-93.8 % between them. Notably, the newly generated Indian sequences (n = 21) demonstrated a high degree of homology, with 98.3-100 % identity. Alignment of the nucleotide sequences revealed 58 variations across the dataset. Additionally, 32 sites exhibited variation within the BvG1 genotype, while 56 sites differed between BvG1 and BvG2 genotypes. Within different B. vogeli populations, the nucleotide diversity (π) was low, but the haplotype diversity (Hd) was high. The haplotype diversity of the Indian population, BvG1 genotype, and the combined dataset was ∼0.8 suggesting a high haplotype diversity. The median-joining haplotype network displayed a total of 21 haplotypes, out of which six haplotypes consisted of more than one sequence (2-25 sequences). Haplotype distribution showed significant geographical structuring, with most haplotypes confined to a single country. Only two haplotypes (9.52 %; Hap_1 and Hap_4) were shared between countries, whereas 19 haplotypes (90.48 %) were country-specific. Hap_1, Hap_6, and Hap_4 were the most representative haplotypes, comprising 25, 10, and four sequences, respectively. India exhibited the highest number of haplotypes (h = 13) followed by China (h = 4), the United States of America (h = 3), Taiwan and Tunisia (h = 2), and Thailand (h = 1). Both location-wise and genotype-wise median joining haplotype networks clustered the haplotypes in two groups, representing two distinct genotypes (BvG1 and BvG2). The B. vogeli populations between Thailand and Tunisia exhibited the highest genetic differentiation (FST = 0.80) with a low gene flow (Nm = 0.125) between them. Results of AMOVA revealed a higher genetic variation within populations (69.43 %) as compared to the variation between them (30.57 %). Neutrality indices and the mismatch distributions of the Indian population and the overall dataset of B. vogeli indicated a constant population size to population expansion and population expansion, respectively, with the presence of two distinct genotypes. These data provide information about parasite population genetics and highlight the importance of starting a long-term molecular surveillance program. In conclusion, a high genetic diversity along with the presence of two distinct genotypes of B. vogeli were observed on the basis of internal transcribed spacer regions (ITS1-5.8S-ITS2).

Fatal coinfection of blastocystosis and intestinal trichomoniasis in a rhesus macaque (Macaca mulatta).

A 3-year-old male rhesus macaque was presented at Referral Veterinary Polyclinic-Teaching Veterinary Clinical Complex, with a chief complaint of chronic diarrhoea and swelling of dependent body parts. The patient's history indicates that the monkey had been experiencing diarrhoea for the past month, with 2-3 episodes of vomiting in the last 2 days. Additionally, oedema has developed within the last 2 weeks. The clinical examination findings revealed dullness and depression, the mucus membrane appeared pale, with a temperature-102.1 °F, a respiration rate-28/min, and a heart rate-92/min. The capillary refill time was 4 s. During the physical examination, the animal exhibited oedema on the dependent part of the body and faecal staining around the perineum along with loose yellow stool. Direct saline and iodine mount faecal smear examination revealed the presence of many motile pear-shaped flagellated protozoa and round vacuolated Blastocystis organisms. Giemsa-stained faecal smear cytology confirmed the presence of Pentatrichomonas sp. and Blastocystis sp. along with many microbes. The faecal culture was negative for all pathogenic microbes. The case was diagnosed as co-infection Blastocystosis and intestinal trichomoniasis. The treatment was initiated with a combination of sulfamethoxazole + trimethoprim @ 35 mg/kg body weight and metronidazole @25 mg/kg administered orally once daily for 7 days. Supportive therapy includes hematinic injection (iron sorbitol, folic acid and vitamin B12) @ 1 ml total dose, administered intramuscularly on alternate days for four occasions as well as intravenous infusion of crystalline amino acid @ 5 ml total dose on alternate days for four occasions. To manage vomition, injection ondansetron was administered@0.5 mg/kg intramuscularly, twice daily for 3 days and H2 blockers, including injection ranitidine@2 mg/kg intramuscularly twice daily for 3 days. Electrolyte and probiotic supplementation were administered orally. After 7 days of therapy, the oedema had significantly improved and episodes of vomition were stopped but there was no significant improvement in the episode of diarrhoea and consistency of faeces. Unfortunately, on the 10th day of therapy, the animal suddenly collapsed. Understanding the virulence pattern of opportunistic protozoa in primates is crucial, and identifying suitable therapeutic candidates to prevent fatal outcomes is the need of the hour, especially considering protozoal infections as an important differential diagnosis in gastrointestinal tract-related ailments. Our study successfully demonstrated the co-occurrence of blastocystosis and intestinal trichomoniasis, both uncommon infections with potential zoonotic implications.

Therapeutic management of pseudomalaria in a flock of pigeons with chloroquine.

Two Indian rock pigeons aged 2-3 months presented to the Referral Veterinary Polyclinic and Teaching Veterinary Clinical Complex, Indian Veterinary Research Institute, Utter Pradesh with a history of decreased feed intake, twisting of the neck, and inability to fly. The same symptoms also caused the deaths of two other birds from the same flock. The bird seemed dull and depressed during a clinical examination, had ruffled feathers, a tilted head and circling. Examination of a faecal sample showed no intestinal parasites. Upon observation of a blood smear, many intracytoplasmic characteristic halter-shaped Hemoproteus columbae gametocytes could be detected. The case was diagnosed as pigeon pseudomalaria. The treatment was initiated with chloroquine@10 mg/kg body weight in drinking water for 5 days along with the multivitamin supplementation for one week. Permethrin spray was applied externally to the whole flock in the house to get rid of the fly vector. The clinical state of the birds was evaluated one week after initiation of the therapy. The pigeon had an uneventful recovery and the blood smear examination revealed no haemoparasites.