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Recent evidence suggests that lizards of the family Chamaeleonidae are one of the most heavily parasitized groups of reptiles kept in captivity; however, little is known about the clinical implications of these infections. Relative to other host species, there is a paucity of information on reptile parasites and the breadth of parasites that infect chameleons is not well described. We report a parasitic infection most consistent with organisms belonging to the Mesomycetozoea group in male and female wild-caught jeweled chameleons (Furcifer campani). Clinical features of infection included persistent weight loss, despite increased food intake; cachexia; abnormally increased light- and heat-seeking behavior; coelomic distention; and loose, watery stools. Histologically, there was extensive granuloma formation present in the liver and widespread localization of periodic acid–Schiff- and Grocott's methenamine silver–positive spores resembling those of Dermocystidium sp. in the bone marrow, gastrointestinal tract, and other tissues. A second case of infection with this pathogen also presented with concurrent Mycobacterium sp. throughout the body, suggesting that infection with mesomycetozoean organisms may serve as a primary cause of death, or conversely, may render the infected individual susceptible to secondary, opportunistic infection. The rapid health decline associated with infection in these cases indicates a need to better characterize prevalence and pathogenicity of parasites in captive chameleons. [ABSTRACT FROM AUTHOR]

Here, we report details of a new infectious disease in wild-caught Japanese fire-bellied newts (Cynops pyrrhogaster), a Near Threatened species. Skin lesions consisting of numerous masses were found in the animals near Lake Biwa, Shiga Prefecture, Japan. The gross appearance of the skin lesions showed blister-, cyst-, and/or tumor-like morphology. Various sizes of skin lesions were observed on their entire body surface. Histologically, spherical basophilic cysts, including numerous spores, were observed in the dermis layer. Ultrastructural analysis indicated the presence of main bodies of flagellated zoospores within the spores. While 18s rRNA gene sequencing indicated that the skin lesions were due to dermocystid infection. To our knowledge, this is the first report of dermocystid infection in this amphibian in Japan. Further studies are needed to prevent epidemics and to establish diagnostic and treatment methods. [ABSTRACT FROM AUTHOR]

Abstract The genus Dermocystidium infects a wide range of animals. The host infection often occurs through the ingestion of endospores. The diagnosis depends on wet mounts and histopathological analysis of the affected tissue. The aim of this study was to investigate the incidence of Dermocystidium sp. infection on the skin of farmed striped catfish (Pangasianodon hypophthalmus) from a fish farm located in Fortaleza, Ceará state, northeastern Brazil. From these observations, we determined that 100% of the analyzed animals were infected with Dermocystidium sp. The wet mount and histopathology of the fish lesions revealed spore-filled cysts between the dermis and epidermis, encapsulated by connective tissue. Owing to a lack of research on the parasite and its prevalence among different fish species in Brazil and the rest of the world, additional studies are required to understand their endemicity in fish farms of Brazil, and consequently develop better disease prevention methods and increase the overall productivity.

In autumn 2011 in cyprinid farms located in Iasi on the Jijia river, several infections with bacterial strains and macroscopical external cysts on the skin were diagnosedwhich developed as a result of the stress induced by biotic and abiotic factors. On the examination of the cyst contents the presence of numerous spores was observed, mostly of the Dermocystidium sp genusThe samples were taken from the common carp (Cyprinus carpio) and crucian carp (Carassius auratus gibelio) species from the fish farm as well as from the Jijia River. 35 fish were examined, all of them showing cysts, fragmentation of their dorsal fin and congestion of the gills. Histological examination of the skin showed a field of multiple dermal cysts with round light eosinophilic formations (14-16µm) containing a central refractable body similar to that reported for Dermocystidium sp. Gills samples were taken from the affected areas for the SEM examination with the purpose of evaluating not only aspects of normal morphology, but also aspects of some modifications of the affected areas as well as the presence of the etiologically incriminated bacteria Pseudomonas fluorescens. The isolates were identified through phenotypic methods. All the strains that showed mobility and oxidase-positivity were tested using API 20 NE strip. Consequently, they were taxonomically grouped into the species Pseudomonas fluorescens. The scanning electron microscope (SEM) was used for the first time in the characterization of the bacterial lesions produced by Pseudomonas strains on Cyprinus carpio and Carassius auratus gibelio gills. The diagnosis of septicemia with conditional pathogen species of Pseudomonas fluorescens was correlated with the results of the physico-chemical investigations of water and the data concerning the breeding conditions of the investigated livestock.

The article discusses a study on cyprinids' associated protozoa-bacterial infections from a fish farm on the Jijia river in North-East of Romania. It mentions that study analyzed Dermocystidium spores. The study also performed scanning electron microscopy (SEM) for characterization of bacterial lesions, examination of the samples taken from Carassius auratus gibelio and Cyprinus carpio species, and identification of isolates of bacteria Pseudomonas fluorescens through phenotypic methods.

Bullheads, Cottus gobio, with macroscopic external cysts on the skin and fins measuring up to 3 mm in diameter were detected in the River Allen and its tributaries in southern England between 1992 and 1998. The prevalence of these cysts was up to 50% at some sites. Examination of cyst contents revealed the presence of numerous spores, typical of the genus Dermocystidium, measuring 8 μm in diameter. The parasite developed within well-defined cysts, which were located in the hypodermal connective tissues of the host. No cysts were present on the fins of any of the fish examined. Histological examination revealed a cyst wall consisting of an inner layer of dense eosinophilic material similar to that reported for Dermocystidium spp. forming coenocytic hyphae. No evidence was found of systemic infection or hyphal formation. Spores contained a prominent refractile body, which gave a weakly positive reaction for polysaccharides with the periodic-acid Schiff reaction and was positively stained with acidic dyes. Several examples of ruptured cysts were seen in histological sections and in some of these cases the host epithelial layer was breached, allowing release of the spores to the environment. Morphological features of, and host response towards, the Dermocystidium sp. in bullheads are compared with similar infections in salmonids and other freshwater fish species. [ABSTRACT FROM AUTHOR]

This study confirms the systemic position of Dermocystidium sp. in Nile tilapia (Oreochromis niloticus) internal organs (liver, spleen, kidneys, stomach and intestine). Our work reveals an entire approach for Dermocystidium sp. including prevalence, diagnosis, spores multiplication, experimental infection and histopathological examination. A total of 1388 Nile tilapia (766 cultured fish and 622 wild fish) were collected from May 2012 to May 2014 and screened for Dermocystidium infection. The total prevalence of infection was 35.5% and was higher in wild (45%) than cultured fish (27.8%). The highest rates of infection were recorded in the largest fish and in winter. Several different techniques were employed to detect and identify Dermocystidium sp. from the internal organs of infected hosts including macroscopic examination, microscopic observation of tissue squashes, histological examination and in vitro culture. Infected fish were sluggish and suffered from severe ulceration and black discoloration of the skin. The post-mortem lesion included dark-grayish nodules on internal organs, particularly the liver. Squash preparations from the internal organs revealed spherical spores (signet-ring shape), which is characteristic for Dermocystidium sp. The spores showed multiplication in the freshly dead host tissue. Our study demonstrated new successful attempts for in vitro culture of Dermocystidium either on Eagle's Minimum Essential Medium after adjusting pH of media to 3.5 or on Sabouraud's dextrose agar media enriched with duck decoction 10%. Experimental infection revealed that intra-gastric route was more pathogenic than the immersion route. In histopathological sections from infected fish tissue following natural and experimental infection, spherical spores of Dermocystidium were embedded in the affected tissue. To the best of our knowledge, this study represents the first report of Dermocystidium infection in wild Nile tilapia in Egypt. [ABSTRACT FROM AUTHOR]