Uncovering a neglected canine filarioid in Asia: First evidence of Cercopithifilaria bainae in Thailand and a tale of the evolutionary history within the Cercopithifilaria lineage

Neospora caninum is a significant intracellular protozoan that invades dogs as definitive and intermediate hosts, particularly farm animals as intermediate animal hosts. This parasitic infection leads to extreme financial losses due to reproductive distress and neurological illnesses in dogs. The current study aimed to identify N. caninum in domestic and stray dogs from different areas of Babylon province and to evaluate the influence of risk factors like sex, age, and months, on the ratio of infection. Based on serological tests Indirect Enzyme-Linked Immunosorbent assay, (iELISA), a total of 146 blood samples were collected from dogs, with 76 and 70 samples collected from stray and domestic dogs, respectively, from July to December (2024). The overall prevalence rate was 26.7% (39/146), whereas the infection rate in stray dogs was 36.8% (28/76), which was higher than that in domestic dogs at 15.7% (11/70), with a highly significant difference (p≤0.05). No significant difference was observed (p ≥ 0.05) between the sexes; the proportion of males was 29.3% (22/75) and that of females was 23.9% (17/71). The higher ratio of infection in domestic dogs was investigated in the adult age group, 17.5% (7/41), in comparison with the lower infection rate of 13.7% (4/29) in the puppies, with no significant statistical difference (p ≥ 0.05). A monthly analysis demonstrated a higher infection rate in stray dogs and domestic dogs (34.6%) in September, followed by October (32%), whereas a lower infection rate was found in November (18.1%), followed by December (13%). The present study used serological diagnostic examination methods, particularly ELISA, to identify the critical role of stray and domestic dogs in the epidemiological cycle of neosporrosis and dissemination of N. caninum infection among animals in Babylon Province, Iraq.

Molecular identification of Echinococcus granulosus sensu lato by mitochondrial COX1 and SSU-rDNA markers in dogs in the west of Iran

The aim of the study was to assess whether the hair of stray and domestic dogs in Egypt was contaminated with the eggs of the zoonotic parasite Toxocara canis, and also to identify risk factors for T. canis for contamination. Paired samples of hair and feces were collected from 53 stray and 47 domestic dogs, and hair samples were obtained from a further 11 stray and 9 domestic dogs. All samples were examined to identify T. canis eggs and, if eggs were found, their maturation stage. Eggs were identified in 26.6% of stray and 10.7% of domestic dog's hair samples. A significantly increased risk of embryonated T. canis eggs in hair samples was found in stray dogs ( p = 0.04), stray dogs had 3.18 (95% CI: 1.04–9.74) times the odds of having T. canis eggs present compared with domestic dogs. There was also a significant difference ( p = 0.02) between the mean quantity of eggs per gram in stray (77.6 ± 6.54) and domestic (48.7 ± 6.65) dog's hair. Fecal examination found a T. canis egg prevalence of 35.8% and 21.3% in stray and domestic dogs, respectively. As no domestic dogs which were positive from hair samples had negative fecal samples, this indicates that the presence of T. canis eggs in hair is probably due to self contamination. Two stray dogs had positive hair samples but negative fecal samples indicating that contamination may also be environmental. As both non-embryonated and embryonated T. canis eggs were found in the hair of domestic dogs, direct contact with dogs may be a potential risk factor for transmission of T. canis eggs to humans.

Background. A domestic dog (Canis familiaris) is one of the most common do mestic animals, the diversity of their ecological and social status is determined by their re production and reproduction in cities and rural settlements. In populated areas, dogs have a significant impact on the fauna of the ecosystem. The purpose of the study was to analyze the genetic structure of Penza stray dog population based on the study of individual polymor phism by microsatellite loci of nuclear DNA. Materials and methods. The material for the study was hair samples of domestic and stray dogs collected in the period 2021–2024 in shelters and centers for overexposure of stray animals, on the streets of Penza and provided by pet dog owners. To isolate DNA, 23 wool samples were collected, of which 11 were ob tained from stray dogs and 12 from domestic dogs. To amplify microsatellite DNA fragments consisting of tri- and tetra tandem repeats, the primer systems of the Stock Marks Dog Gen otyping Kit identification panel of the American Kennel Association were used. Results. The approbation of 6 microsatellite systems (PEZ3 F/R, PEZ6 F/R, PEZ8 F/R, FHC2010 F/R, FHC2045 F/R, FHC2079 F/R) showed that they are extremely nonspecific for the DNA matrix obtained from dogs living in the territory of the Russian Federation. Apparently, the genetic lines of the domestic dog of the North American continent are quite different from domestic lines. The obtained microsatellite allelic spectra of DNA samples from stray and domestic dogs are mainly represented by heterozygous sets. At the same time, heterozygosity was slightly higher in the population of stray dogs (0.750) compared with the heterozygosity of domestic dogs (0.670). Conclusions. The performed procedure for DNA extraction from hair samples of domestic and stray dogs revealed its low productivity. For a successful study of the genetic structure of the population of stray animals, more productive methods should be used, for example, tissue biopsy. The results of amplification of marker fragments of microsatellite DNA of stray dogs showed poor performance of the tested microsatellite systems of the dog identification panel of the American Kennel Association. It is necessary to start developing its own panel of microsatellite markers suitable for the identification of dogs of domestic cultural breeding.

Myxobolus gutturocola n. sp. was isolated from the throat of silver carp, Hypophthalmichthys molitrix, in Chongqing, China. Myxospore valves are unsymmetrical and smooth. Mature spores are ellipsoidal in frontal view, measuring 12.5 ± 0.2μm (n = 25) in length, 8.4 ± 0.2μm (n = 25) in width and 7.1 ± 0.2μm (n = 25) in thickness. Each spore has two pyriform and unequal sizes polar capsules, the large one with 5.7 ± 0.2μm in length × 3.6 ± 0.2μm in width and the small one with 4.6 ± 0.2μm in length × 2.6 ± 0.1μm in width. Polar filaments are coiled seven or eight turns in the large polar capsule and four or five turns in the small polar capsule. The coils are arranged almost perpendicularly to the longitudinal axis of the polar capsule. Morphological analysis revealed that M. gutturocola n. sp. is distinct from related species of Myxobolus Bütschli, 1882. Molecular analysis has demonstrated that its SSU rDNA sequences do not match with any available sequences in GenBank. Phylogenetic analysis of the SSU rDNA sequences indicated this species clustered in a clade composed exclusively of parasites infecting the fishes of the Leucisini lineage and most closely related to Myxobolus pavlovskii isolated from the gill filaments of silver carp in Hungary.

Molecular phylogeny by Bayesian analysis and description of a new species of Henneguya, a parasitic cnidarian from Astyanax bimaculatus (Linnaeus, 1758) (Characiformes: Acestrorhamphidae) in Caatinga: A biome with neglected biodiversity data.

The micromorphology and histology of anuran skin, particularly in Thai species, remain relatively understudied. Anurans use their tongues for prey capture and their hands and feet for adhesion and mating, suggesting a close relationship between micro-surface features and histological structure. Information on Sylvirana nigrovittata is particularly limited. This study provides a detailed examination of the micro-surface and histological characteristics of the tongue, fingers, toes, nuptial pad, and humeral gland in S. nigrovittata. Specimens collected from Phu Luang Wildlife Sanctuary in Loei province, northeastern Thailand, were studied using scanning electron microscopy (SEM) for micro-surface features and H&E staining for histological details. SEM micrographs revealed that the tongue was cordate-shaped, with about 75% of its surface covered by filiform papillae and 25% by fungiform papillae housing taste buds. Filiform papillae were trapezoidal, averaging 23.88±5.68 µm in width and 38.83±6.57 µm in length, while fungiform papillae were disc-like, averaging 52.95±14.64 µm in width and 66.70±15.88 µm in length. Digital pads on fingers and toes presented prismatic cells, with fingertip cells averaging 7.09±0.97 µm in width and 11.81±1.24 µm in length, and toe cells averaging 8.40±1.37 µm in width and 11.28±1.63 µm in length. Subdigital surfaces were smoother, containing squamous cells with dimensions of 10.65±3.21 µm in width and 21.29±4.35 µm in length. Subarticular tubercles were composed of prismatic cells with hexagonal or pentagonal surfaces, averaging 10.02±2.85 µm in width and 13.08±1.94 µm in length. Nuptial pad displayed cylindrical structures with dome-like tips, averaging 24.01±3.96 µm in width and 21.16±4.37 µm in length, and feature mucous openings. They consisted of a thick keratinized stratified squamous epithelium and a dense dermis with specialized mucous glands. Humeral gland exhibited rough surfaces with squamous cells and microridges, showing both small and large mucous openings, with average cell dimensions of 16.23±1.70 µm in width and 19.11±2.05 µm in length. Histological analysis confirmed that these structures were predominantly composed of keratinized stratified squamous epithelium, with variations in dermal collagen density and mucous gland distribution. This study enhances our understanding of the skin and gland morphology in S. nigrovittata, highlighting on its anatomical and functional adaptations.

The resolution of the taxonomic dilemma of Myxobolus colossomatis and description of two novel myxosporeans species of Colossoma macropomum from Amazon basin

Henneguya azevedoi n. sp. is described from the piava (Leporinus obtusidens). Between 2005 and 2007, 60 fish were collected from the Mogi-Guaçu River near Cachoeira de Emas Falls located in the municipality of Pirassununga, state of São Paulo, Brazil. A total of 70% had plasmodia of the parasite. The plasmodia were white, spherical, and measured 40-200 μm in diameter. Histopathological analysis revealed that the development of the parasite was intralamellar and caused stretching of the epithelium, with accentuated deformation, as well as compression of the capillary and adjacent tissues. Ultrastructural analysis revealed that the wall of the plasmodium was a single membrane in direct contact with the host cells and contained pinocytic canals that extended into the plasmodium. The development of the parasite was asynchronous, with the earliest stages at the periphery and mature spores in the central region. Mature spores were elongated in the frontal view [mean ± standard deviation (range)]: 45.2 ± 0.6 (45.0-47.0) μm in total length, 10.0 ± 0.07 (9.9-10.2) μm in body length, 35.6 ± 0.9 (34.9-36.5) μm in caudal process length, and 4.4 ± 0.4 (4.0-5.0) μm in body width. The polar capsules were elongated and equal in size: 3.8 ± 0.3 (3.5-4.0) μm in length and 1.0 μm in width. The polar filaments were coiled in six to seven turns and perpendicular to the axis of the capsule. Scanning electron microscopy revealed smooth valves and a conspicuous rim around the spore body. This is the first time that a myxosporean has been reported in L. obtusidens.

Introduction:Contaminated environment with canine parasitic eggs is the main source for toxocariasis and other geohelminth infections of humans. This study aimed to determine the prevalence and associated risk factors for intestinal parasitic infections in dogs and the degree of soil contamination with Toxocara eggs in Kandy and Gampaha districts in Sri Lanka.Methods:A total of 188 fecal samples from both stray and domestic owned dogs from Gampaha district and Kandy district were collected. In addition, soil samples were collected from home gardens and public places. Hypochlorite recovery technique and zinc sulfate floatation method were used to concentrate eggs in soil samples.Results:The prevalence of intestinal parasitic infections of domestic and stray dogs in Gampaha district was 38.2% and 42.9%, respectively, while in Kandy district, it was 41.1% and 50%, respectively. Hookworms were the most common parasitic infection among domestic dogs (18.5%), while Toxocara spp. were the most common among stray dogs (17.2%). Intestinal parasitic infections were significantly more prevalent among female dogs than males. Age, deworming, immunization, immunization time, and living in rural areas were not significantly associated with intestinal parasitic infections in domestic dogs. A total of 4% and 4.5% soil samples were contaminated with Toxocara spp. eggs in Gampaha and Kandy districts, respectively.Conclusions:The higher prevalence of intestinal parasitic infections in dogs could be a major public health issue. Implementations of programs to improve the awareness of parasitic infections among pet owners and control strategies need to decrease the risk of infections to both animal and human health.

BackgroundIn China the highest prevalence of echinococcosis is in Tibet Autonomous Region (TAR). The government has issued documents and implemented comprehensive prevention and control measures focusing on controlling the source of infection of echinococcosis. It was very important to understand the implementation and effect of infectious source control measures. The purpose of this study was to examine the implementation of measures to control infectious source (domestic and stray dogs) in TAR and to assess their effectiveness.MethodsWe collected data on domestic dog registration and deworming and stray dog sheltering in 74 counties/districts in the TAR from 2017 to 2019. Fecal samples from domestic dogs were collected from randomly selected towns to determine Echinococcus infection in dogs using coproantigen ELISA. We analyzed the data to compare the canine rate of infection between 2016 and 2019. The data analysis was performed by SPSS statistical to compare dog infection rate in 2016 and 2019 by chi-square test, and ArcGIS was used for mapping.ResultsFrom 2017 to 2019, 84 stray dog shelters were built in TAR, and accumulatively 446,660 stray or infected dogs were arrested, sheltered, or disposed of. The number of domestic dogs went downward, with an increased registration management rate of 78.4% (2017), 88.8% (2018), and 99.0% (2019). Dogs were dewormed 5 times in 2017, 12 times in 2018, and 12 times in 2019. The dog infection rate was 1.7% (252/14,584) in 2019, significantly lower than 7.3% (552/7564) from the survey of echinococcosis prevalence in Tibet in 2016 (P < 0.05).ConclusionBetween 2017 and 2019, the number of stray dogs and infection rate of Echinococcus spp. in domestic dogs decreased significantly, indicating that dogs were effectively controlled as a source of infection in TAR and reflecting a significant decrease in the risk of echinococcosis transmission.Graphical

The Amazonian fish Colossoma macropomum harbors high myxosporean diversity: A description of three novel species from a fish farm

Neospora caninum a protozoan parasite causes abortions in cattle, as well as neurological disorders and reproductive problems in dogs. This study was conducted to detect Neospora caninum in fecal samples of stray and domestic dogs and determine the effects of sex, age, months and areas in the infection rate in Baghdad city by using molecular technique (Nested PCR– n PCR) during the period of the beginning of January to October (2021). The total infection rate was 10% (10/100).Higher infection rate 15.30% (8/52) was recorded in stray dogs than domestic dogs 4.16 % (2/48), and males than females (12.72% and 6.66%) respectively. The higher infection rate (7.70%) was recorded in the age group more than 5 years, while no infection rate (0.00%) was found in the age group less than 2 years. A higher infection rate (20.00%) was recorded in May while no infection rate (0.00%) was found in January and February. A significant (P≤0.01) difference was found in the infection rate among areas and the higher infection rate was recorded in Al-Shalaa (20.00%), while no infection rate (0.00%) was found in Al-Salam and Al-Gzalia areas.

Dogs as a source for the spreading of enteric parasites including zoonotic ones in Giza Province, Egypt

The ascarid nematode, Toxocara canis, which causes Toxocariasis in dogs, is a member of the Toxocaridae family and genus Toxocara, and that is accidentally infects humans. The study was conducted to investigate the presence of T. canis in dogs in Karbala, Iraq. The study extended from January to October, 2023. This project is the first of its kind in Iraq to molecularly detect the parasite in stray dogs in Karbala and to report its prevalence in domestic and stray dogs by utilizing conventional PCR and fecal flotation techniques while controlling for risk factors. One hundred (50 stray and 50 domestic) dog fecal samples were included. The findings revealed that 26 (26%) of the total dog fecal samples were tested positive using the PCR method. In details, the infection rate was 10% in domestic dogs and 42% in stray dogs. Moreover, the rate was 9.3 in adult dogs and 38.5% in puppies. The results showed that age, lifestyle, and infection rate all showed significantly (p &lt; 0.01) correlated relationships in dogs. The correlation between T. canis infection rates and sex was not statistically significant (p &gt; 0.01). The PCR-based sequencing of T. canis isolates indicated a high percentage of similarities with strains from different geographical regions. The study findings indicate higher rates of T. canis infection in adult and puppy stray dogs, explaining the extent of the infection among domestic dogs and stray dogs, using the latest laboratory methods for diagnosis PCR with the use of the phylogenetic tree to show the extent of similarity with species found in neighboring countries. The study findings are important by giving initial epidemiological data for future studies and control of the parasite.