Dermatophytosis in domestic cats: Identification, and treatment in an Indian context.

The surge in domestic cat adoption across India, particularly the rising preference for high-pedigree cats, coupled with environmental factors, has resulted in increased incidence of dermatophytosis among feline companions. Despite this growing concern, there is a noticeable scarcity of studies in India delving into the etiological factors contributing to dermatophytosis in cats. This disease is a threat to animal health and carries public health significance, given that cats are recognized reservoir hosts for Microsporum canis, a common dermatophyte affecting humans and animals. This study endeavours to identify the dermatophytes affecting cats and establish a standardized therapeutic regimen while accounting for the local stigma surrounding the regular bathing of cats. The study involved the examination of 82 cats presenting dermatological lesions, when subjected to cultural examination in dermatophyte test medium revealed 36 afflicted with dermatophytes. Isolates were presumptively identified by staining using lactophenol cotton blue, Chicago sky blue 6B, and Calcofluor white stains. Molecular-level identification of the isolates was confirmed through PCR-RFLP, amplifying the Internal Transcribed Spacer Sequence of 16 s rDNA, followed by restriction digestion using the Mva1 enzyme. Among the thirty-six isolates, 29 were identified as M. canis, while the remaining 7 were M. gypseum. The cases were categorized into five groups and treated with Lime Sulphur dip, 4 % chlorhexidine shampoo, a shampoo containing 2 % miconazole and 4 % chlorhexidine, oral itraconazole alone, and a combination of oral itraconazole with lime-Sulphur dip. Statistical analysis revealed that the response was notably swifter with lime Sulphur dip when considering only topical therapy. Moreover, the mycological cure was most expeditious when combining Lime Sulphur dip with oral itraconazole. These findings underscore the pivotal role of topical biocides in feline dermatophytosis treatment, potentially reducing the reliance on specific antifungals and thereby contributing to the mitigation of antimicrobial resistance emergence.

Detection of lytic phage infecting flavour-producing strain of Lacticaseibacillus paracasei in the dairy effluents of Kerala.

The performance of the starter culture is a critical factor that decides the quality of fermented milk. Dahi is a fermented milk product popular in India made using a mixed starter culture of lactic acid bacteria comprising acid and flavour producers. The prevalence of bacteriophages in the dairy environment can critically affect the activity of these starter cultures resulting in starter failure. As there is little information available on the occurrence of bacteriophages in the dairy environment of Kerala, this research communication examines the presence of lytic bacteriophages acting against three potential flavour-producing strains of Lacticaseibacillus paracasei (Lc. paracasei). Dairy effluent samples were screened for the presence of phages against the strains of Lc. paracasei by the multiple host enrichment method. Plates showing clearance zone in spot assay were confirmed for the presence of phages by double-layer agar assay. The plaques obtained in the double-layer agar assay were purified for further identification by next-generation sequencing. A bacteriophage infecting one of the three strains of Lc. paracasei was detected by the plaque assay and the blast annotation of the bacteriophage sequence found 86.05% similarity of the phage to Siphoviridae family. The study endorses the need for monitoring phages in the dairy environment to control phage-related starter failure in the state of Kerala.

Description and development of Auerbachia ignobili n. sp. (Cnidaria: Myxosporea: Bivalvulida) from the giant trevally, Caranx ignobilis (Forsskål, 1775) from Indian waters.

The present study describes a new species of myxosporean, Auerbachia ignobili n. sp., infecting the hepatic bile ducts of Caranx ignobilis (Forsskål, 1775). Myxospores are club-shaped with a broad anterior region and a narrow, slightly curved and blunt caudal extension, measuring 17.4 ± 1.5 µm in length and 7.5 ± 7.4 µm in width. Shell valves asymmetrical, with a faint suture line, and enclosed a single, elongate-elliptical polar capsule with a ribbon-like polar filament, arranged in 5-6 coils. Developmental stages included early and late presporogonic stages, pansporoblast, and sporogonic stages with monosporic and disporic plasmodia. A. ignobili n. sp. differs from the other described species of Auerbachia in the shape and dimensions of the myxospores and polar capsules. The molecular analysis generated ∼1400 bp long SSU rDNA sequences and the present species exhibited a maximum similarity 94.04-94.91% with A. chakravartyi. Genetic distance analysis indicated the lowest interspecies divergence of 4.4% with A. chakravartyi. In phylogenetic analysis, A. ignobili n. sp. was positioned independently with a high bootstrap value (1/100) and appeared as sister to A. maamouni and A. chakravartyi. Fluorescent in situ hybridization and histology indicates that the parasite develops within the hepatic bile ducts. Histological studies did not reveal any pathological changes. Considering the morphological, morphometric, molecular, and phylogenetic differences coupled with the differences in host and geographic locations, the present myxosporean is treated as a new species and named A. ignobili n. sp.

Characterization of Filisoma argusum n. sp. (Acanthocephala: Cavisomatidae Meyer, 1932) infecting the spotted scat, Scatophagus argus (Linnaeus, 1766) from the Indian coast.

The present paper describes Filisoma argusum n. sp. (Cavisomatidae), an acanthocephalan parasite infecting the intestine of the spotted scat, Scatophagus argus (Linnaeus, 1766), in the south-west coast of India. The prevalence is 18% (mean intensity: 1.61 and abundance: 1-4 worms/host). Filisoma argusum n. sp. is morphologically characterized by a creamy-white, cylindrical, elongate, aspinose, and robust trunk; a collar-like neck; and a cylindrical proboscis with 18-20 longitudinal rows of hooks, with 19-22 hooks/row. Proboscis receptacle long, double-walled. Lemnisci digitiform, equal, longer than proboscis receptacle. Females 79.14 ± 33.69 × 0.593 ± 0.19 mm; males 32.62 ± 2.98 × 0.46 ± 0.071 mm. Males with four cement glands; bulbous muscular copulatory bursa with six digitiform rays. SEM studies revealed smooth hooks, sensory pits, and epidermal micropores. Histopathological changes at the site of parasite attachment included inflammation, hemorrhage, sloughing of epithelium, and detachment of mucosal layer of the intestine. In molecular and phylogenetic analyses, the parasite occupied an independent position within the Cavisomatidae clade with high bootstrap values for both ITS1-5.8S and ITS2, and mt-CO1 regions. Considering the morphologic and morphometric differences with previously described species of Filisoma along with its phylogenetic positioning, the present acanthocephalan is treated as a new species and the name Filisoma argusum n. sp. is proposed.

Morphological and molecular characterization of Ceratomyxa xanthopteri n. sp. (Myxosporea: Ceratomyxidae) from the marine ornamental fish Acanthurus xanthopterus Valenciennes 1835 (Acanthuridae) off Vizhinjam coast, Kerala.

A new species of Ceratomyxa infecting the gallbladder of the marine ornamental fish Acanthurus xanthopterus collected from the Vizhinjam coast of Kerala is described. The parasite exhibited a prevalence of 100%. Mature spores recovered from the gallbladder were slightly crescentic with rounded lateral extremities and possessed convex anterior and slightly concave to straight posterior margins. Spore valves two, equal, joined by a straight and prominent suture. Myxospores measured 5.5 ± 0.6 µm in length and 15.9 ± 2.3 µm in thickness. Polar capsules two, equal, spherical, positioned anteriorly on either sides of the suture, 2.3 ± 0.2 µm long and 2.2 ± 0.2 µm wide. Polar filament with four to five coils, 21.2 ± 0.6 µm when extruded. Posterior angle 173.6 ± 5.2°. Early sporogonic stages and monosporic, disporic, and multisporic plasmodial stages were spherical to irregular in shape, with or without filopodia. Histopathologic analysis revealed that spores and developing stages were attached to the gallbladder wall as well as found free in the lumen. Morphologic and morphometric comparison of the present parasite with known species of Ceratomyxa indicated significant differences. In molecular and phylogenetic analyses, the present myxosporean revealed high divergence with related forms and occupied an independent position within the Ceratomyxa clade with high nodal support. Considering the morphological, morphometric, molecular, and phylogenetic dissimilarities with the previously described species of Ceratomyxa and the differences in host and geographic locations, the present species of myxosporean is treated as new and is named Ceratomyxa xanthopteri n. sp.

Ellipsomyxa ariusi sp. nov. (Myxosporea: Ceratomyxidae), a new myxosporean infecting the gallbladder of threadfin sea catfish Arius arius in India.

The present study describes a new species of myxosporean, Ellipsomyxa ariusi sp. nov., infecting the gallbladder of the threadfin sea catfish Arius arius (Hamilton, 1822). E. ariusi sp. nov. is characterized by bivalvular, ellipsoid or elongate-oval myxospores with smooth spore valves and a straight suture, arranged at an angle to the longitudinal spore axis. Mature myxospores measured 10.1 ± 0.8 µm in length, 6.8 ± 0.5 µm in width and 7.7 ± 0.7 µm in thickness. Polar capsules are equal in size and oval to pyriform in shape. They are positioned at an angle to the longitudinal myxospore axis and open in opposite directions. Polar capsules measured 2.8 ± 0.3 µm in length and 2.5 ± 0.4 µm in width; polar filaments formed 4-5 coils, and extended to 32.2 ± 2.1 µm in length. Monosporic and disporic plasmodial stages attached to the wall of gallbladder. Molecular analysis of the type specimen generated a 1703 bp partial SSU rDNA sequence (MN892546), which was identical to the isolates from 3 other locations. In phylogenetic analyses, genus Ellipsomyxa appeared monophyletic and E. ariusi sp. nov. occupied an independent position in maximum likelihood and Bayesian inference trees with high bootstrap values. The overall prevalence of infection was 54.8% and multiway ANOVA revealed that it varied significantly with location, year, season, sex and size of the fish host. Histopathological changes associated with E. ariusi sp. nov. infection included swelling, vacuolation and detachment of epithelial layer, reduced mucus production and altered consistency and colour of bile. Based on the morphologic, morphometric and molecular differences with known species of Ellipsomyxa, and considering differences in host and geographic locations, the present species is treated as new and the name Ellipsomyxa ariusi sp. nov. is proposed.

Ortholinea scatophagi (Myxosporea: Ortholineidae), a novel myxosporean infecting the spotted scat, Scatophagus argus (Linnaeus 1766) from southwest coast of India.

A new species of myxosporean, Ortholinea scatophagi n. sp. infecting the urinary bladder of the spotted scat, Scatophagus argus (Linnaeus 1766) is described. O. scatophagi n. sp. is characterized by spherical myxospores with a slightly flattened anterior end and equal spore valves with extra sutural ridges on its surface; measured 7.34 ±â€¯0.67 µm in length, 6.90 ±â€¯0.71 µm in width and 6.48 ±â€¯0.37 µm in thickness. Two polar capsules, equal, spherical to oval in shape, arranged diametrically opposite and measured 2.59 ±â€¯0.42 µm in length and 2.24 ±â€¯0.35 µm in width. Polar filaments, 21.84 ±â€¯2.86 µm long, with four to five coils. Scanning electron microscopy revealed the presence of extra sutural ridges on spore surface. Pansporoblasts spherical to irregular in shape, measured 31.08 ±â€¯2.67 µm in length and 13.88 ±â€¯5.40 µm in width; Monosporic, disporic and polysporic plasmodial stages were observed; plasmodia spherical or irregular in shape with granular cytoplasm containing refractile granules. The species was compared with 23 existing nominal species of Ortholinea, based on morphology and morphometry. Molecular analysis resulted in a 1773 bp long SSU rDNA sequence (GenBank accession number MN 310514). In phylogenetic analyses the present parasite clustered with other members of Ortholinea, under the freshwater urinary clade. Considering the morphologic, morphometric and molecular differences with previously described species of Ortholinea, and differences in host and geographic locations, the present species is treated as new and the name Ortholinea scatophagi n. sp.is proposed.

Morphological and molecular characterization of Chloromyxum argusi n. sp. (Myxosporea) infecting the urinary bladder of Scatophagus argus Linnaeus 1766 (Scatophagidae) from the southwest coast of India.

The present paper describes a new species of Chloromyxum infecting the urinary bladder of the estuarine fish, Scatophagus argus, from the southwest coast of India. The parasite exhibited an overall prevalence of 41.93%; the prevalence is influenced by host size and seasons. Mature spores are subspherical, measure 9.40 ± 0.66 by 9.32 ± 0.87 µm, and are characterized by the presence of sutural and extra-sutural ridges, binucleated sporoplasm, and a pair of caudal extensions. Four pyriform, unequal polar capsules with raised polar filament discharge pores and ribbon-like polar filaments are present. Polar filament coils numbered four to five in large polar capsules and three in small polar capsules. Pansporoblast is irregular with granulated cytoplasm and has fine villosites on its surface. Plasmodia are spherical/irregular with monosporic and polysporic forms. In molecular and phylogenetic analysis, the myxosporean stands out with a high bootstrap value and was positioned as a sister branch of Chloromyxum kurisi. In view of the morphologic, morphometric, and molecular differences with the existing species of Chloromyxum, and considering the differences in hosts and geographic locations, the present species is treated as new and the name Chloromyxum argusi n. sp. is proposed.

Morphometric and molecular characterisation of Tenuiproboscis keralensis n. sp. infecting marine and brackish water fishes from the south-west coast of India with a note on morphological plasticity.

A new species of acanthocephalan infecting marine and brackish water fishes from the south-west coast of India is described. The parasite belongs to the genus Tenuiproboscis, and the fish hosts include Lutjanus argentimaculatus, L. ehrenbergii, Siganus javus, Epinephelus malabaricus, E. coioides, Scatophagus argus, Parascolopsis aspinosa, Caranx ignobilis, Gerres filamentosus and Lates calcarifer. The parasite inhabits mid- and hindgut regions and is characterised by an elongated, cylindrical, bulbous and posteriorly tapering metasoma and a claviform proboscis having 14-15 rows of 14-15 hooks each. Females larger than males, measured 3898.16-10,318.00 µm (6430.00 ± 1417.30) in length and 458.93-1435.68 µm (929.81 ± 250.39) in width. Males measured 3234.89-8644.20 µm (5729.50 ± 1176.60) in length and 388.30-1584.61 µm (795.88 ± 184.12) in width. Parasites recovered from different host species showed morphological/morphometric variations. However, principal component analysis (PCA) revealed significant overlapping of characters indicating their similarities. Proboscis profiling based on variations in size and position of hooks also yielded similar results. Further, in molecular phylogenetic analysis, parasites from different fish hosts formed a monophyletic clade with strong bootstrap support, again indicating their conspecific nature. These morphological/morphometric variations can be ascribed to differences in host species. Morphology and morphometrics in combination with PCA, proboscis profiling and molecular analysis suggest the present acanthocephalan parasite is different from other described species of Tenuiproboscis. Hence, it is considered as a new species and named T. keralensis n. sp. Prevalence, intensity and abundance of the parasite in different hosts are also discussed.

Molecular and morphological descriptions of Ceratomyxa collarae n. sp. and Ceratomyxa leucosternoni n. sp. from marine ornamental fishes of Indian waters.

Two novel species of Ceratomyxa infecting marine ornamental fishes from Indian waters are described. Marine ornamentals, Chaetodon collare and Chaetodon decussatus, collected from Vizhinjam, along the southwest coast of India and Acanthurus leucosternon collected from Lakshadweep islands of Arabian Sea revealed Ceratomyxa infections in their gall bladders. Mature spores of Ceratomyxa from Chaetodon collare and Chaetodon decussatus were elongate and slightly crescentic, with rounded ends, and measured 5.20 ± 0.32 µm in length and 16.32 ± 1.29 µm in thickness. Polar capsules spherical, equal in size and measured 2.23 ± 0.16 µm long and 2.24 ± 0.20 µm wide. Posterior angle measured 157.75 ± 8.650. Principle Component Analysis and molecular analysis using partial SSUrDNA sequences showed the isolates from these two hosts to be identical. Morphological, morphometric and molecular analysis using partial SSUrDNA sequences revealed the taxonomic novelty of isolates and are hence treated as Ceratomyxa collarae n. sp. Mature spores of Ceratomyxa from Acanthurus leucosternon were elongate, slightly tapering with rounded ends, and measured 7.34 ± 0.92 µm in length and 24.37 ± 2.34 µm in thickness. Shell valves were equal, joined by a narrow suture line. Polar capsules spherical in shape, equal in size, 2.59 ± 0.32 µm long and 2.46 ± 0.32 µm wide, and polar filament measured 18.68 ± 2.54 µm. Based on morphological, morphometric and molecular analyses, the present species of Ceratomyxa is distinct, considered as a new species and named Ceratomyxa leucosternoni n. sp. The paper also discusses the prevalence of the recovered parasites and host specificity of Ceratomyxa collarae n. sp.

Relative expression of bacterial and host specific genes associated with probiotic survival and viability in the mice gut fed with Lactobacillus plantarum Lp91.

The present investigation was aimed at studying the relative expression of atpD (a key part of F1F0-ATPase operon), bsh (bile salt hydrolase), mub (mucus-binding protein) and MUC2 (mucin) genes in mouse model for establishing the in vivo functional efficacy of Lactobacillus plantarum Lp91 (MTCC5690) by reverse transcription-quantitative PCR (RT-qPCR). The atpD gene was significantly up-regulated to 2.0, 2.4 and 3.2 folds in Lp91 after 15, 30 and 60 min transit in the stomach of mice. The maximal significant (P<0.00) level of relative bsh gene expression was recorded in Lp91 with 41.6 fold in comparison to only 5.0 fold in reference strain Lp5276 after seven days of mice feeding. Simultaneously, mub gene expression increased to 12.8 and 22.7 fold in both Lp91 and Lp5276, respectively. The expression level of MUC2 was at the level of 1.6 and 2.1 fold in the host colon on administration with Lp91 and Lp5276 feeding, respectively. Hence, the expression of atpD, bsh, mub, MUC2 could be considered as prospective and potential biomarkers for screening of novel probiotic lactobacillus strains for optimal functionality in the gut.