Occurrence of Hymenolepis diminuta: a potential helminth of zoonotic importance in murid rodents

The study reveals the prevalence of a potential rodent-borne zoonotic helminth species, Hymenolepis diminuta in commensal rodents caught from irrigated and rain-fed areas of Swat, Pakistan. Three hundred and fifty rodents (269 rats and 81 mice) trapped during vegetative, flowering/fruiting and mature/harvesting stages of crops were studied from 2011-2013. Hymenolepisdiminuta eggs were identified on the basis of their shape, size, colour and markings on the surface of the egg shell and three pairs of embryonic hook-lets. Overall prevalence of H. diminuta was 3.14% (n=11/350). The highest prevalence 3.49% (n=5/143) of H. diminuta was noted at harvesting stages of the crops whereas the lowest 2.59% (n=2/77) during vegetative stage. Infection was higher in males 3.25% (n=7/215) than females 2.96% (n=4/135). Adult rodents were highly infected while no sub-adult was found infected. Infection was higher in mice 3.70% (3/81) than rats 2.69% (8/269) while no significance (p=1.0000:0.1250 to 32.00 CI). Rats and mice appears to show the most suitable reservoirs by hosting H. diminuta a zoonotic helminth. The presence of these rodents in all possible habitats can act as a main channel of transferring parasites through various habitats and can pose a hazard to humans in the area.

ALIEN SPECIES OF FISH HELMINTHS OF BELARUS

The article provides data on the species composition of alien helminth species, which infest introduced fish species in pond fish farms, and also the literature data on natural reservoirs of Belarus. Seven alien helminth species have been revealed in introduced fish in reservoirs of Belarus ( Khawia sinensis Hsü, 1935, Schyzocotyle acheilognathi (Yamaguti, 1934) , Caryophyllaeus fimbriceps Annenkova-Chlopina, 1919, Philometroides cyprini (Ishii, 1931), Dactylogyrus dulkeiti Bychowsky, 1936, Bothriocephalus claviceps (Goeze, 1782) , Anguillicola crassus Kuwahara 1974). All species of helminths excluding the nematode A.crassus and the cestode B.claviceps - parasites of the eels Anguilla anguilla , were introduced to Belarus with the seeding of Cyprinus carpio haematopterus (Linnaeus, 1758) from the Far East. The invasive species of helminths ( K. sinensis, S. acheilognathi, P. cyprini, A. crassus ), which affect fishery by causing the death of farmed fish, are singled out.

The Invasive Bank Vole (Myodes glareolus): A Model System for Studying Parasites and Ecoimmunology during a Biological Invasion

The primary driver of the observed increase in emerging infectious diseases (EIDs) has been identified as human interaction with wildlife and this increase has emphasized knowledge gaps in wildlife pathogens dynamics. Wild rodent models have proven excellent for studying changes in parasite communities and have been a particular focus of eco-immunological research. Helminth species have been shown to be one of the factors regulating rodent abundance and indirectly affect disease burden through trade-offs between immune pathways. The Myodes glareolus invasion in Ireland is a unique model system to explore the invasion dynamics of helminth species. Studies of the invasive population of M. glareolus in Ireland have revealed a verifiable introduction point and its steady spread. Helminths studies of this invasion have identified enemy release, spillover, spillback and dilution taking place. Longitudinal studies have the potential to demonstrate the interplay between helminth parasite dynamics and both immune adaptation and coinfecting microparasites as M. glareolus become established across Ireland. Using the M. glareolus invasion as a model system and other similar wildlife systems, we can begin to fill the large gap in our knowledge surrounding the area of wildlife pathogen dynamics.

First Data on the Helminth Community of the Smallest Living Mammal on Earth, the Etruscan Pygmy Shrew, Suncus etruscus (Savi, 1822) (Eulipotyphla: Soricidae)

Suncus etruscus is the smallest living mammal on Earth by mass. Most adults weigh 1.8–3 g with a body length of 35–48 mm. Catching it in small mammal traps in nature is extremely difficult due to its minute size, and therefore special trapping methods must be used. We had the unique opportunity of studying, for the first time, the helminth parasites of 166 individuals of S. etruscus, part of the largest collection in the world, which belonged to the French scientist Dr Roger Fons (1942–2016). A total of 150 individuals were captured in the Banyuls-Cerbère area (France) and 16 in the island of Corsica (France). We found seven helminth species, specifically, the cestodes Joyeuxiella pasqualei larvae, Mesocestoides sp. larvae, Staphylocystis claudevaucheri, S. banyulsensis, S. cerberensis, and Pseudhymenolepis sp., and the nematodes Aonchotheca sp. and Nematoda gen. sp. larvae. Neither trematodes nor acanthocephalans were detected. We provide prevalences, infracommunity compositions, and helminth associations. The adult helminth community of S. etruscus seems to be highly specific, i.e., oioxenous, and linked to its insectivore diet. Due to its small size, S. etruscus has undergone numerous physiological adaptations that have probably influenced its helminth spectrum as well as its helminth specificity.

Helminths of domestic and wild chicken birds (Aves: Galliformes) of Uzbekistan

The purpose of the research is studying existing fauna and ecology of Galliform helminths in biogeocenoses of Uzbekistan.Materials and methods. Parasitic worms were collected from chicken-like birds of the terrestrial cenoses of Karakalpakstan and North-eastern Uzbekistan. Birds were studied in all seasons of 2018–2020. Wild birds – Himalayan hen, keklik, grey partridge, quail and pheasant, were hunted by local hunters during hunting seasons, while domestic birds - chickens, turkeys and guinea fowls were uncovered from different types of poultry farms. The study of birds was carried out by well-known methods. It was examined 913 wild and 755 domestic chicken-like animals. The detected cestodes and trematodes were fixed in 70% alcohol, and the nematodes were fixed in Barbagallo liquid. The determination of helminth species was carried out according to the well-known guidelines of domestic and foreign authors.Results and discussion. We found that helminthoses were widespread among representatives of Galliformes in Uzbekistan. Total helminth infections in domestic and wild Galliformes were 50.5%. In infected birds, 44 helminth species were identified, among which 10 species were cestodes, 12 species were trematodes and 22 species were nematodes. Helminth species diversity was the most extensive in the domestic chicken (36 species), turkey (21), and partridge (20). For the first time for the helminth fauna in Galliformes in Uzbekistan, we identified 3 trematode species – Brachylaema fuscatus, Collyriclum faba and Echinostoma miyagawai, and 10 nematode species of the genera Capillaria, Aonchotheca, Ascaridia, Heterakis, Dispharynx, Streptocara, Tetrameres, Diplotriaena and Ornithofilaria.

Prevalence, Intensity and Risks Involved in Helminth Infections in Domestic Mountain Pony and Balkan Donkey in Nature Park Stara Planina, Serbia

Background: This study aimed to investigate the prevalence, intensity and risk factors (age and gender) promoting the intestinal helminthic infections of the Domestic mountain ponies and Balkan donkeys in Serbia. Methods: Prevalence, intensity and risk factors influencing helminth infection in horses (n=39) and donkeys (n=18) at the site of Nature Park Stara Planina, were studied from May to Sep 2015. The presence of one or several gastrointestinal helminth species was confirmed by faecal flotation in 97.43% of horses and 88.88% of donkeys included in the monitoring. The identified helminth species were Trichostrongylus axei, Strongylus edentatus, S. vulgaris, Parascaris equorum, Dictyocaulus arnfieldi and Anoplocephala magna in 84.61%, 46.15%, 5.13%, 58.97%, 94.87% and 38.46% of horses, respectively. The significant association of infection with P. equorum and sex of horses was established. (χ2=13.33, P<0.01). Results: The prevalence of parasitic helminths identified in donkeys was the following: D. arnfieldi, T. axei, Pa. equorum, S. vulgaris, A. margna and Strongyloides westeri in 55.55%, 38.89%, 27.78%, 22.22% and 22.22% of donkeys, respectively. Moreover, the mean faecal egg count was higher in donkeys (369.9 EPG - egg per gram) than in horses (250.2 EPG). The association between the age and the mean EPG was significant (P<0.05) in both equine species. Conclusion: The results of the investigation provided basic information that can be helpful for planning strategic control of nematode infection in equine population in Nature Reserves in Serbia.

The helminth fauna of brown trout (Salmo trutta) from a sub-alpine lake revisited after 40 years with introduced European minnow (Phoxinus phoxinus)

The helminth fauna of brown trout (Salmo trutta) in the Norwegian subalpine lake, Øvre Heimdalsvatn was studied by examination of gills, eyes, body cavity, kidney, stomach, pyloric region and intestine in a total of 112 brown trout randomly sampled in June, July, and September 2011. Ten helminth species, Discocotyle sagittata, Phyllodistomum umblae, Crepidostomum farionis, C. metoecus, Diplostomum sp., Proteocephalus sp., Cyathocephalus truncatus, Dibothriocephalus ditremus, D. dendriticus, and Capillaria sp. were identified. These data were compared to data from the period 1969 to 1972, just after the first record of the European minnow (Phoxinus phoxinus) in 1969. All ten helminth species, except D. dendriticus, were also present in 1969–72. However, a few major changes in infection intensities have occurred. The cestode D. ditremus and the trematode Diplostomum sp., both with piscivorous birds as final hosts, had markedly higher relative densities (abundance) in brown trout in 2011 compared to 1969–72, while the two Crepidostomum species showed a substantial decline in relative densities. We suggest that these changes may be indirectly related to the establishment and subsequent population increase of European minnow in the lake. The abundance of minnows may have increased the food basis for the piscivorous birds, primarily mergansers and the black-throated diver that now regularly forage in the lake. In addition, there have been changes in the littoral invertebrate community, including species serving as intermediate hosts of some of the brown trout parasites.

Gastrointestinal Helminths Increase Bordetella bronchiseptica Shedding and Host Variation in Supershedding

Multi-species infections have been suggested to facilitate pathogen transmission and the emergence of supershedding events. However, how the interactions between co-infecting pathogens affect their dynamics of shedding, and how this is related to the host immune response, remains largely unclear. We used laboratory experiments and a modeling approach to examine temporal variations in the shedding of the respiratory bacterium Bordetella bronchiseptica in rabbits challenged with one or two gastrointestinal helminth species. Experimental data showed that rabbits co-infected with one or both helminths shed significantly more B. bronchiseptica by direct contact with an agar petri dish than rabbits with bacteria alone. There was also evidence of synergistic effects when both helminth species were present (triple infection). Co-infected hosts generated supershedding events of higher intensity and more frequently than hosts with no helminths. Model simulations revealed that the two helminths affected the relative contribution of neutrophils and specific IgA and IgG to B. bronchiseptica neutralization in the respiratory tract. In turn, these changes led to differences in the magnitude and duration of shedding among the various types of infection. However, the rapid variation in individual shedding, including supershedding, could not be explained by the interactions between infection and immune response at the scale of analysis that we used. We suggest that local rapid changes at the level of respiratory tissue probably played a more important role. This study provides novel insight into the role of helminths to the dynamics of respiratory infections and offers a quantitative explanation for the differences generated by two helminth species.

Helminth fauna of birds of prey (Strigiformes: Strigidae, Tytonidae) in the Non-Black Earth Region of the Russian Federation

The purpose of the research is studying helminths of carnivorous birds of the order of owls (Strigiformes) found in the Non-Black Earth Region of the Russian Federation.Materials and methods. From 2015 to 2020, complete helminthological dissections were carried out by the Skryabin method for 72 birds of the order of owls after their spontaneous death: 8 specimens of the short-eared owl Asio flammeus, 6 specimens of the Ural owl Strix uralensis, 4 specimens of the little owl Athene noctua, 9 specimens of the barn owl Tyto alba, 19 specimens of the tawny owl S. aluco, and 26 specimens of the long-eared owl A. otus. The study material was provided by rehabilitation centers and veterinary clinics in Moscow City and the Moscow, Tula and Kaluga regions. The helminths were fixed according to generally accepted methods; the species was identified taking into account specific morphological characters.Results and discussion. Total infection rate in owls was 89.9%. All studied birds were found to have mixed infections with two or more types of helminths. We identified 15 helminth species including 3 species of trematodes (Neodiplostomum attenuatum, Strigea falconis, S. strigis), 2 species of cestodes (Cladotaenia globifera, Paruterina candelabraria), 9 species of nematodes (Syngamus trachea, Cyrnea leptoptera, Microtetrameres inermis, Synhimantus laticeps, Porrocaecum depressum, P. spirale, Capillaria tenuissima, Baruscapillaria falconis, and Capillaria sp.) and 1 acanthocephalian species (Centrorhynchus aluconis). For the first time, new hosts were identified for the following helminth species: the barn owl, short-eared owl and little owl for the trematode N. attenuatum, the Ural owl and little owl for S. falconis, the long-eared owl for the nematode S. trachea, the short-eared owl and tawny owl for C. leptoptera, and the tawny owl for M. inermis.