Molecular detection and genetic characterization of Coxiella-like endosymbionts in dogs and ticks infesting dogs in Northeast India.

An epidemiological study was performed to determine the role of dogs and ticks infesting dogs in the transmission of Q fever in humans and animals from April 2019 to March 2020 in the northeastern hill states of India. In total, 245 pet and stray dogs irrespective of age or sex were sampled, without specific inclusion or exclusion criteria. In total, 478 ticks belonging to three species were detected, namely Rhipicephalus sanguineus, Rhipicephalus (Boophilus) microplus and Hyalomma anatolicum anatolicum. The DNA extracted from blood and tick samples was assayed for molecular characterization of Coxiella burnetii targeting the 16S rRNA and superoxide dismutase (SOD) genes. Amplified PCR products were purified, cloned and custom sequenced. PCR assay showed 3.3% (8/245) of the dogs were positive for Coxiella-like bacteria. Coxiella-like bacterial DNA was detected in adult fully engorged females of R. sanguineus (7.7%, 13/168), R. (B.) microplus (3.3%, 4/123) and H. anatolicum (1.9%, 1/54). Coxiella-like bacterial DNA lacked in adult male or nymphal stage. The infection rate did not vary significantly between seasons, nor according to sex or age of the host. Six nucleotide sequences of 16S rRNA and SOD genes are discussed.

Molecular detection of Babesia microti in laboratory mice from India.

BACKGROUND & OBJECTIVES: For detection and molecular characterization of Babesia microti in laboratory mice from India. METHODS: A total of 625 mice were screened by peripheral blood smear examination and subsequently was confirmed by PCR using a piroplasm conserved primer set (Piro A/B). Nested PCR was done using a species-specific primer targeting the gene encoding the small subunit ribosomal RNA (18S rRNA). The PCR products were cloned, purified and sequenced. A total of 12 isolates were obtained. The sequences were aligned and phylogenetic trees were prepared with other published Babesia spp. sequences. RESULTS: B. microti was detected with a total infection rate of 8.80%. The higher rate of infection was observed by species specific PCR (8.80%) than examined by blood smear (7.20%). Sequence and phylogenetic analysis showed that Babesia species detected in mice were genetically identical to the genotypes of B. microti and can be easily distinguished from other genotypes of Babesia parasites by neighbour joining and maximum likelihood method. Intra-species analysis indicated that all the twelve isolates from six North-Eastern states of India have a close identity but inter-species showed genetic reservoir host for transmission of babesial infection to humans. INTERPRETATION & CONCLUSION: The detection of Babesia microti may suggest that laboratory mice may serve as potential reservoir host for human infection and possibility of innovative way of diagnosing and control of human babesiosis.

Incidence of cutaneous habronemosis in Manipuri ponies in India.

Information pertaining to parasitic fauna and parasitic diseases in Manipuri ponies in India is not available. Moreover, no systematic studies have been undertaken on cutaneous habronemosis in Manipuri ponies which is a common skin problem of Manipuri ponies as reported by pony owners. Keeping in the view of the importance of parasitic infections in veterinary health coverage particularly in Manipuri ponies, the present study was planned. A survey of natural cases of cutaneous habronemosis followed by molecular confirmation of species involved and treatments were done. Out of 200 ponies examined, nine cases (4.5%) of cutaneous habronemosis was recorded. Gross examination revealed raised and ulcerated wounds with necrotic tissues covered with yellowish-tan granulation. Histopathological study revealed eosinophilic granuloma and in the center of the granuloma with necrotic debris. Remnants of the Hebronema larvae with infiltrating neutrophils surrounded by proliferating fibrous tissue with numerous eosinophils, macrophages and lymphocytes were also observed. Molecular detection of Habronema sp. was confirmed by semi-nested PCR. Sequence analysis revealed larvae of H. muscae was the common spirurid species responsible for producing cutaneous habronemosis in Manipuri ponies. Subsequently, sequence submitted to NCBI GenBank and accession number obtained (MH038181). Surgical removal of necrotic tissue, ivermectin injection along with antibiotics successfully cured all the lesions in infected ponies.Results confirmed occurrence of cutaneous habronemosis in Manipuri ponies in India.

Molecular Characterization of Chitin Synthase Gene of Demodex canis from Mizoram, India.

AIMS: Canine demodicosis is a parasitic condition affecting the skin of dogs. The present study was designed to characterize chitin synthase gene of Demodex canis. The molecular technique was used for better understanding of this gene. METHODS: A total of 75 dogs which are reared as pets with or without showing any skin lesions were examined during the study period. Skin scrapings were examined by indirect method using 10% potassium hydroxide solution under 10 × microscope. DNA samples were extracted from positive skin samples and were subjected to PCR for molecular identification. RESULTS: A total of 25 dogs irrespective of age, sex, breed or coat showed positive result for D. canis. The PCR revealed a single amplified product of 339 bp length which exactly matched with D. canis. The chitin synthase gene was amplified by PCR, subsequently cloned, sequenced, and compared with available data in GenBank for the particular gene of D. canis. Only one single nucleotide polymorphism (SNP) was noticed at 231 position of the chitin synthase gene sequence when compared to other isolates. CONCLUSION: The molecular technique confirms with the morphological identity of D. canis. This report signifies the value of peculiar tool to identify 'follicular mite' even from apparently healthy skin.

Ticks (Acari: Ixodidae) infestation on cattle in various regions in Indonesia.

BACKGROUND AND AIM: Ticks (Ixodidae) not only cause blood loss in cattle but also serve as vectors for various diseases, thus causing direct and indirect losses. Moreover, tick infestation can cause significant economic losses. This study aimed to identify the diverse species of ticks infesting cattle in five different regions in Indonesia. MATERIALS AND METHODS: Tick specimens were obtained from local cattle in five different areas in Indonesia. The morphology of the specimens was macroscopically and microscopically evaluated, and the resulting data were descriptively and qualitatively analyzed. RESULTS: In total, 1575 ticks were successfully collected from 26 animals. In total, two genera and three species, namely, Rhipicephalus microplus, Haemaphysalis bispinosa, and Rhipicephalus pilans, were identified. The cattle in Yogyakarta and Riau were infested by H. bispinosa, while the cattle in Sukabumi, Bali, and Lombok were infested by R. microplus and R. pilans. The level of infestation varied among regions, with R. microplus being the most commonly found species. CONCLUSION: The results of this study revealed that cattle in different regions of Indonesia were infested by variable numbers of tick species. In particular, the cattle in Yogyakarta and Riau were solely infested by H. bispinosa; this is a new finding in terms of the distribution of tick species in the country. Increased tick infestation in cattle decreases productivity and causes health problems; therefore, it deserves serious attention. Our findings can help in the formulation of an effective strategy for controlling and preventing cattle tick infestation in the country.

Quantification and expression studies of IL-13 gene in response to experimental infection with Haemonchus contortus in Garole and Sahabadi sheep.

To evaluate the role of IL-13 gene in Garole/Sahabadi sheep against resistant/susceptibility to Haemonchus contortus five Garole sheep (Group I) with consistently showing low egg per gram of faeces (EPG) (≤150) and another five Garole sheep (Group II) with high EPG (≥500) were selected and fed orally with active H. contortus third stage (L3) larvae at the dose rate of 500 larvae/kg body weight. Five Sahabadi sheep (Gr-III) known susceptible to H. contortus were also challenged with the same dose as the previous groups. Blood was collected from each group on day 0, 7 and 14days post infection (dpi). The serum level of IL-13 cytokine was evaluated by ELISA at different days of post infection. The ovine IL-13 was partially isolated and the RNAm level of IL-13 expression was studied by real-time PCR at different days post infection. In the resistant Garole sheep (Gr-I) the concentration of IL-13 cytokine increased significantly (P≤0.05) 14days PI compared to susceptible Garole (Gr-II)/Sahabadi (Group-III). In similar way the relative expression of IL-13 in group I (Gr-I) was found more than seven fold higher than Gr-II and Gr-III on 14 dpi. The Th2 type immune response to H. contortus characterized by higher serum level of IL-13 cytokine and IL-13 gene expression indicated that IL-13 gene plays a vital role for the reduced establishment and/or survival of established H. contortus in resistant Garole sheep.