Epidemiology and diversity of gastrointestinal tract helminths of wild ruminants in sub-Saharan Africa: a review.

This review summarises studies on distribution, diversity, and prevalence of gastrointestinal helminth infections in wild ruminants in sub-Saharan Africa. The results showed that 109 gastrointestinal tract (GIT) helminth species or species complexes were recorded in 10 sub-Saharan African countries. South Africa reported the highest number of species because most studies were carried out in this country. Eighty-eight nematode species or species complexes were recorded from 30 wild ruminant species across eight countries. The genus Trichostrongylus recorded the highest number of species and utilised the highest number of wild ruminant species, and along with Haemonchus spp., was the most widely distributed geographically. Fifteen trematode species or species complexes were reported from seven countries. The genus Paramphistomum recorded the highest number of species, and Calicophoron calicophoron was the most commonly occurring species in sub-Saharan African countries and infected the highest number of hosts. Six cestode species or species complexes from one family were documented from 14 wild hosts in seven countries. Moniezia spp. were the most commonly distributed in terms of host range and geographically. Impala were infected by the highest number of nematodes, whilst Nyala were infected by the highest number of trematode species. Greater kudu and Impala harbored the largest number of cestodes. The prevalence amongst the three GIT helminths taxa ranged between 1.4% and 100% for nematodes, 0.8% and 100% for trematodes, and 1.4% and 50% for cestodes. There is still limited information on the distribution and diversity of GIT helminths in wild ruminants in most sub-Saharan African countries.

First molecular insights into gastrointestinal helminths of domestic birds in the Caspian Sea Littoral of Iran with an emphasis on the One Health concern.

The current investigation was carried out during the period from July 2022 to March 2023, aiming to investigate the prevalence of gastrointestinal helminths in domestic birds collected from traditional markets in Guilan province. One hundred forty-eight domestic birds, including chickens (Gallus gallus domesticus), domestic ducks (Anas platyrhynchos domesticus), greylag geese (Anser anser), and domestic turkeys (Meleagris gallopavo domesticus) were examined. Totally, 42.56% of the investigated birds were positive for helminthic parasites. Morphological analysis revealed varying infection rates among birds: Echinostoma revolutum (5.40%), Hypoderaeum conoideum (2.02%), Cloacotaenia megalops (0.67%), Hymenolepididae family (4.05%), Ascaridia galli (16.89%), and Heterakis gallinarum (4.72%). The investigation involved molecular analysis of the 18S and ITS1 + 5.8S + ITS2 rRNA gene regions. The findings indicated that the 18S region of nematode isolates exhibited a similarity of 92 to 100% with sequences in the GenBank, whereas trematode and cestode isolates showed a gene similarity ranging from 88 to 99%. The ITS regions of nematode, trematode, and cestode isolates exhibited genetic similarities ranging from 87 to 100%, 73-99%, and 75-99%, respectively. Furthermore, phylogenetic analysis confirmed the categorization of the identified species within the Ascaridiidae, Heterakidae, Hymenolepididae, and Echinostomatidae families, indicating their close affinity with previously documented species. Implementing precise control measures such as consistent monitoring, adequate sanitation protocols, and administering anthelmintic treatments is crucial for effectively managing parasitic infections in free-range and backyard poultry farms. Additionally, conducting further surveys is advisable to assess the impact of these parasites on the health and productivity of poultry in the investigated area.

Prevalence and risk factors of gastrointestinal helminths infection in Brazilian horses: A retrospective study of a 12-year (2008-2019) diagnostic data.

Understanding gastrointestinal parasite distribution is crucial for effective control programs in horses. This study reports the prevalence of helminth infections in horses and selected risk factors (i.e., breed, age, climate, season) by analyzing 19,276 fecal samples from the Laboratory of Veterinary Clinical Parasitology, in Curitiba, Southern Brazil. The analyses were carried out from 2008 to 2019, coming from 153 stud farms located in 60 municipalities of nine Brazilian states. The parasite prevalence was 73.3%, with 72.1% present in the adult population and 80.6% in young horses. Strongyles were present in 100% horse farms. Strongyles had a prevalence of 72.1% with a mean FEC of 453.53 (+/- 717.6). Parascaris spp. had a prevalence of 5.8% and a FEC of 17.11 (+/- 149.2). The tropical wet/monsoon climate (Am) showed the lowest FEC for strongyles and Parascaris spp. when compared to the other climates. In the logistic regression analysis, young horses exhibited 4.6 times higher odds ratio (OR) (3.9-5.5) of Parascaris spp. and 1.2 (1.1-1.4) times higher OR of strongyles egg shedding when compared to adults (P < 0.001). Summer presented a higher risk for Parascaris spp. and Strongyles eggs when compared to the other seasons (P < 0.001). Mangalarga Marchador, Criollo, and Crossbred breeds were identified with higher OR of Parascaris spp. egg shedding than Thoroughbred. The extensive prevalence of strongyles across ages, seasons, breeds, and climates alerts for the risk of clinical manifestations in equines raised on pastures designing optimal health management and parasite control strategies worldwide.

Endoparasitic helminth fauna and diet of Geophagus sveni (Pisces) in Upper Paraná River basin.

In freshwater ecosystems, parasite infection patterns are influenced by factors including spatial-temporal variations, host diet, and habitat. Fish often change diets, affecting their parasite communities. This study focused on non-native host fish Geophagus sveni, aiming to characterize diet and endoparasitic helminth fauna patterns in the invaded area, investigating spatial and seasonal possible differences of endoparasite infections and correlating with host diet, in São José dos Dourados River and Tietê River areas. The host fish were collected in these areas during the dry and rainy season using gillnets. The endoparasites were collected and preserved in alcohol and identified using taxonomic methods, and stomach contents were examined for diet analysis. Parasitism descriptors were calculated and evaluated spatially and seasonally by ANOVA and the Kruskal-Wallis tests. PERMANOVA assessed G. sveni diet differences, and RDA correlated the endohelminth abundance with the host diet. Two endoparasites were recorded: metacercariae of Austrodiplostomum compactum (Trematoda) and larvae and adults of Raphidascaris (Sprentascaris) lanfrediae (Nematoda). Spatial differences were observed for the mean abundance and prevalence of R. (S.) lanfrediae and A. compactum prevalence. Seasonal variations of parasitic descriptors occurred for the nematode in the Tietê River area. The detritus and aquatic insects were the most consumed items by G. sveni. Detritus consumption positively correlates with nematode abundance. The findings indicate that factors such as artificial channels and rainfall, which can influence resource availability, may affect the fish's diet and potentially influence the structure of its endoparasite community. The study emphasizes the importance of understanding trophic chain-transmitted parasites and calls for further research in Neotropical environments.

Metabarcoding of protozoa and helminth in black-necked cranes: a high prevalence of parasites and free-living amoebae.

Parasites and free-living amoebae (FLA) are common pathogens that pose threats to wildlife and humans. The black-necked crane (Grus nigricollis) is a near-threatened species and there is a shortage of research on its parasite diversity. Our study aimed to use noninvasive methods to detect intestinal parasites and pathogenic FLA in G. nigricollis using high-throughput sequencing (HTS) based on the 18S rDNA V9 region. A total of 38 fresh fecal samples were collected in Dashanbao, China, during the overwintering period (early-, middle I-, middle II-, and late-winter). Based on the 18S data, eight genera of parasites were identified, including three protozoan parasites: Eimeria sp. (92.1%) was the dominant parasite, followed by Tetratrichomonas sp. (36.8%) and Theileria sp. (2.6%). Five genera of helminths were found: Echinostoma sp. (100%), Posthodiplostomum sp. (50.0%), Euryhelmis sp. (26.3%), Eucoleus sp. (50.0%), and Halomonhystera sp. (2.6%). Additionally, eight genera of FLA were detected, including the known pathogens Acanthamoeba spp. (n = 13) and Allovahlkampfia spp. (n = 3). Specific PCRs were used to further identify the species of some parasites and FLA. Furthermore, the 18S data indicated significant changes in the relative abundance and genus diversity of the protozoan parasites and FLA among the four periods. These results underscore the importance of long-term monitoring of pathogens in black-necked cranes to protect this near-endangered species.

Title: Métabarcoding des protozoaires et des helminthes chez les grues à cou noir : forte prévalence de parasites et d'amibes libres. Abstract: Les parasites et les amibes libres sont des agents pathogènes courants qui constituent une menace pour la faune et les humains. La grue à cou noir (Grus nigricollis) est une espèce quasi menacée et les recherches sur sa diversité parasitaire sont insuffisantes. Notre étude visait à utiliser des méthodes non invasives pour détecter les parasites intestinaux et les amibes libres pathogènes chez G. nigricollis en utilisant le séquençage à haut débit basé sur la région V9 de l'ADNr 18S. Au total, 38 échantillons de matières fécales fraîches ont été collectés à Dashanbao, en Chine, au cours de la période d'hivernage (début, milieu I, milieu II et fin de l'hiver). Sur la base des données 18S, huit genres de parasites ont été identifiés, dont trois parasites protozoaires : Eimeria sp. (92,1 %) était le parasite dominant, suivi de Tetratrichomonas sp. (36,8 %) et Theileria sp. (2,6 %). Cinq genres d'helminthes ont été trouvés : Echinostoma sp. (100 %), Posthodiplostomum sp. (50,0 %), Euryhelmis sp. (26,3 %), Eucoleus sp. (50,0 %) et Halomonhystera sp. (2,6 %). De plus, huit genres d'amibes libres ont été détectés, y compris les agents pathogènes connus Acanthamoeba spp. (n = 13) et Allovahlkampfia spp. (n = 3). Des PCR spécifiques ont été utilisées pour identifier davantage les espèces de certains parasites et amibes libres. En outre, les données 18S ont indiqué des changements significatifs dans l'abondance relative et la diversité des genres des parasites protozoaires et des amibes au cours des quatre périodes. Ces résultats soulignent l'importance de la surveillance à long terme des agents pathogènes chez les grues à cou noir pour protéger cette espèce quasi menacée.

Host weight, seasonality and anthropogenic factors contribute to parasite community differences between urban and rural foxes.

Pathogens often occur at different prevalence along environmental gradients. This is of particular importance for gradients of anthropogenic impact such as rural-urban transitions presenting a changing interface between humans and wildlife. The assembly of parasite communities is affected by both the external environmental conditions and individual host characteristics. Hosts with low body weight (smaller individuals or animals with poor body condition) might be more susceptible to infection. Furthermore, parasites' mode of transmission might affect their occurrence: rural environments with better availability of intermediate hosts might favour trophic transmission, while urban environments, typically with dense definitive host populations, might favour direct transmission. We here study helminth communities (141 intestinal samples) within the red fox (Vulpes vulpes), a synanthropic host, using DNA metabarcoding of multiple marker genes. We analysed the effect of urbanisation, seasonality and host-intrinsic (weight, sex) variables on helminth communities. Helminth species richness increased in foxes with lower body weight and in winter and spring. Season and urbanisation, however, had strong effects on the community composition, i.e., on the identity of the detected species. Surprisingly, transmission in two-host life cycles (trophic transmission) was more pronounced in urban Berlin than in rural Brandenburg. This disagrees with the prevailing hypothesis that trophically transmitted helminths are less prevalent in urban areas than in rural areas. Generally, co-infestations with multiple helminths and high infection intensity are associated with lighter (younger, smaller or low body condition) animals. Both host-intrinsic traits and environmental drivers together shape parasite community composition and turnover along urban-rural gradients.

The white grunt, Haemulon plumierii (Lacepède, 1801) as paratenic and definitive host of two acanthocephalan species, with the description of a new species of Dollfusentis (Palaeacanthocephala: Leptohynchoididae) from the Yucatán Peninsula, Mexico.

Acanthocephalans are a group of obligate endoparasites that alternate between vertebrates and invertebrates to complete their life cycles. Occasionally, the same individual host acts as a definitive or paratenic host for different acanthocephalan species. In this study, acanthocephalans were sampled in marine fish in three localities of the Yucatán Peninsula; adults and cystacanths were recovered from the intestine and body cavity, respectively, of Haemulon plumierii from off the coast of Sisal, Yucatán. Ribosomal DNA sequences (small and large subunits) were used to test the phylogenetic position of the species of the genus Dollfusentis, whereas the mtDNA gene cox 1 was used for assessing species delimitation. The cox 1 analysis revealed an independent genetic lineage, which is recognized herein as a new species, Dollfusentis mayae n. sp. The new species is morphologically distinguished from the other six congeners by having a cylindrical proboscis armed with 22-25 longitudinal rows bearing 12 hooks each. The cystacanths were morphologically identified as Gorgorhynchus medius by having a cylindrical trunk covered with tiny irregular spines on the anterior region, and a cylindrical proboscis armed with 17-18 longitudinal rows of 21 hooks each; small and large subunit phylogenetic analyses yielded G. medius within the family Isthomosacanthidae, suggesting that Gorgorhynchus should be transferred to this family from Rhadinorhynchidae where it is currently allocated.

Morphology, genetic characterization and phylogeny of Moniliformis tupaia n. sp. (Acanthocephala: Moniliformidae) from the northern tree shrew Tupaia belangeri chinensis Anderson (Mammalia: Scandentia).

A new species of Moniliformis, M. tupaia n. sp. is described using integrated morphological methods (light and scanning electron microscopy) and molecular techniques (sequencing and analysing the nuclear 18S, ITS, 28S regions and mitochondrial cox1 and cox2 genes), based on specimens collected from the intestine of the northern tree shrew Tupaia belangeri chinensis Anderson (Scandentia: Tupaiidae) in China. Phylogenetic analyses show that M. tupaia n. sp. is a sister to M. moniliformis in the genus Moniliformis, and also challenge the systematic status of Nephridiacanthus major. Moniliformis tupaia n. sp. represents the third Moniliformis species reported from China.

Gastrointestinal helminths infection of free-roaming cats (Felis catus) in Southeast Iran.

BACKGROUND: Cats in Iran are definitive hosts for several zoonotic intestinal helminths, such as Toxocara cati, Dipylidium caninum, Toxascaris leonina, Physaloptera praeputialis and Diplopylidium nolleri. OBJECTIVE: This study aimed to determine the prevalence of intestinal helminth infection in free-roaming cats in southeast Iran, a region with a high free-roaming cat population. METHODS: From January 2018 to December 2021, 153 cadavers of free-roaming cats from Southeast Iran were necropsied for intestinal helminth infections. The carcasses were dissected, and the digestive systems were removed. The esophagus, stomach, small intestine, caecum and colon were tightly ligated. All adult helminths were collected, preserved and identified. RESULTS: The prevalence of gastrointestinal helminth infections was 80.39% (123/153). Of the cats from Kerman, 73% (73/100) were infected with at least one helminth, including D. caninum 70% (70/100), T. leonina 8% (8/100) and P. praeputialis 17% (17/100). Concurrent infection with two helminth species was found in 16% (16/100) and of three species infections was found in 3% (3/100) of the cats. Of the cats from Zabol, 94.33% (50/53) were infected with at least one of the helminths, including D. caninum 69.81% (37/53), T. leonina 11.32% (6/53), P. praeputialis 37.73% (20/53) and T. cati 5.66% (3/53). Concurrent infection with two helminth species was found in 28.3% (15/53), and three species were found in 1.88% (1/53) of the cats. Helminth infections were more prevalent in older cats. There was no association between sex and infection rate. CONCLUSION: Based on the very high prevalence of zoonotic intestinal helminth infections in free-roaming cats in southeast Iran, the potential public health risk emphasizes the need for intersectoral collaboration, particularly the provision of health and hygiene education to high-risk populations, such as pre-school and school-age children.

Assessing the applications and efficacy of using helminthophagous fungi to control canine gastrointestinal parasites.

Helminths are a major challenge in dog breeding, particularly affecting young animals and posing a significant zoonotic risk. The widespread use of anthelmintics to treat gastrointestinal helminth infections in companion animals is common. However, these chemical products generate residues that can have adverse effects on animal, human and environmental health. In addition to the challenge of parasite resistance to treatment, there is an urgent need to explore and discuss complementary and sustainable methods of controlling helminthiases in these animals. In this context, nematophagous or helminthophagous fungi have emerged as a potential tool for the control of environmental forms of helminths. The purpose of this review is to emphasize the importance of these fungi in the control of free-living forms of helminth parasites in companion animals by highlighting the research that has been conducted for this purpose. In vitro experiments demonstrated the efficacy of fungi like Pochonia chlamydosporia, Arthrobotrys robusta, and Monacrosporium thaumasium in trapping and reducing helminth infective forms. These findings, along with soil contamination studies, suggest the feasibility of using helminthophagous fungi as a sustainable and effective strategy for environmental control. The current literature supports the potential of these fungi as an environmentally friendly solution for managing helminthiasis in dogs, benefiting both animal health and public welfare.

The Description of Neoechinorhynchus miniovalis n. sp. (Acanthocephala: Neoechinorhynchidae) from the Mudskipper Boleophthalmus dussumieri Valenciennes (Gobiiformes: Oxudercidae) in Shatt Al-Basrah Canal Southern Iraq.

PURPOSE: The aim of this article is to describe a new and unusual species of Neoechinoprhynchus Stiles & Hassall, 1905 from the Arabian Gulf coast off Iraq. METHODS: Routine methods for examination of fish hosts and recovery of acanthocephalean parasites were followed. Parasites were cleaned, relaxed overnight in refrigerated water then fixed in cold 70% ethanol. Standard procedure for staining, dehydration, clearing in xylene and mounting in Canada balsam was followed. RESULTS: Neoechinorhynchus miniovalis n. sp. is described from five whole-mounted specimens collected from the mudskipper Boleophthalmus dussumieri Valenciennes (Oxudericidae) captured in Shatt Al-Basrah Canal, Iraq in 2008. It is distinguished from other species of Neoechinorhynchus Stiles and Hassall, 1905 by a combination of the following diagnostic characters: very small ellipsoid trunk with tapering posterior end and correspondingly small size organs; body wall with similar thickness dorso-ventrally; proboscis wider than long with long anterior hooks having prominent roots; hooks in second and third circles much smaller and rootless; receptacle 5-6 times as long as proboscis with a triangular cephalic ganglion at its base; no para-receptacle structure; lemnisci relatively long and equal, not reaching anterior testis; all male reproductive structures contiguous in posterior two-thirds of trunk; testes equatorial and much wider than long; anterior testis smaller than posterior testis; large syncytial cement gland with six giant nuclei; cement reservoir adjacent to anterior end of sperm vesicle adjacent to Saefftigen's pouch. No sexual dimorphism except that the trunk is more rounded in females than in males. The female reproductive system is about one-third as long as the trunk with the selective apparatus in two positions and uterine bell angulating ventrad. Female lemnisci are longer than in males. Comparisons with worldwide and North American-related species that have partially similar features are made. CONCLUSIONS: The finding of Neoechinorhynchus miniovalis n. sp. with unusual small body and wide ellipsoid shape acanthocephalan is considered the first acanthocephalan species belonging to Neoechinorhynchus reported from Palearctic region compared to similar seven species reported only from Neotropical (three species), Nearctic regions (two species), far east (one species) and oriental (one species).

Morpho-molecular characterisation of two new and two previously reported species of Acanthogyrus (Acanthogyrus: Quadrigyridae) from freshwater fishes in India.

Of the total 47 species in the subgenus Acanthosentis, 43 have been reported from the freshwater fishes of Asia. Amin et al. (2017) provided a key to the 23 species of the genus Acanthogyrus reported from the Indian subcontinent. The present study reports two new species: Acanthogyrus bispinosa n. sp. and A. garciai n. sp. from Cirrhinus mrigala Hamilton and Labeo calbasu Hamilton, respectively, and two previously described species: A. golvani Gupta and Jain, 1980 and A. hereterospinus Khan and Bilqees, 1990 from L. rohita Hamilton and L. catla Hamilton, respectively. A. bispinosa n. sp. comprises 3 circles of 6 proboscis hooks each. Trunk spines in A. bispinosa n. sp are divided into two groups: anterior and posterior separated by unarmed region, which has not been previously reported in the subgenus. Anterior spines are present in 7-8 and 7-10 circles in females and males, respectively, whereas posterior spines are in 23-28 and 31-38 circles in males and females, respectively. A. garciai n. sp. comprises 3 circles of 6-8 hooks each and a single set of trunk spines is present in A. garciai n. sp., comprising 35-42 and 25-45 circles in males and females, respectively. All four species were also characterised based on the 18S, 28S, and ITS1-5.8S-ITS2 rRNA molecular markers. The Bayesian inference tree generated based on these markers showed distinct identities of all the species, with a significant molecular divergence, ranging from 3.2 to 53.6%.

Redescription of Illiosentis cetratus Van Cleave, 1945 (Acanthocephala: Illiosentidae) from Menticirrhus undulatus (Girard) in California, with notes on Illiosentis furcatus from Peru.

Illiosentis Van Cleave et Lincicome, 1939 initially included two species: Illiosentis furcatus Van Cleave et Lincicome, 1939 found in the West Atlantic from Cape Cod in Massachusetts, USA to northern Argentina and Illiosentis cetratus Van Cleave, 1945 with restricted distribution in the Pacific coast of southern California. We are reporting I. furcatus from Peru for the first time and describe a population of I. cetratus from the California corbina, Menticirrhus undulatus (Girard), from southern California. The proboscis hook formula was 14 longitudinal rows for I. furcatus of 18-23 hooks each compared to 16 rows of 19-24 hooks each reported by Van Cleave (1945). We complete the inadequate description of I. cetratus with new information on sexual differentiation in the length of the trunk, dorsal vs. ventral hooks, hook roots, trunk spines, two types of anterior recurved rooted hooks vs. posterior rootless straight hooks, measurements of dorsal and ventral hooks and spines, shape of hook roots, terminal position of the female gonopore, and of position of the cephalic ganglion at the anterior margin of the trunk. We also include new details of the reproductive system in both sexes including Saefftigen's pouch and cement gland ducts. We present new SEM and light microscope images. The Energy Dispersive X-ray analysis (EDXA) shows a high level of sulfur in anterior, middle and posterior hooks in various hook sites, as well as spectra of hook tips with a higher relative concentration of sulfur compared to other hook sites. For the placement of I. cetratus, phylogenetic analysis of sequences of three molecular markers, 18S, 28S rRNA and mitochondrial cox 1 genes, was performed with other related available sequences. The resulting analysis illustrated that I. cetratus was nested within a separate clade along with species of two genera, Dentitruncus truttae Sinzar, 1955 and Neotegorhynchus cyprini Lisitsyna, Xi, Orosová, Barcák et Oros, 2022 represented our species of Illiosentis separate from species of Tegorhynchus Van Cleave, 1921 (as also according to the morphology) with which the Illiosentis species were previously synonymised.

Review of the concept of Profilicollis Meyer, 1931 with a description of Profilicollis rancoensis n. sp. (Acanthocephala: Polymorphidae) from the freshwater crab, Aegla abtao Schmitt, 1942 (Decapoda: Anomura) in Chile, with a key to congeneric species.

Profilicollis rancoensis n. sp. is the tenth species of Profilicollis Meyer, 1931 which includes 9 other species mostly known from marine decapod crabs and shore birds. Cystacanths of P. rancoensis are described from the dominant freshwater crab Aegla abtao in Ranco Lake, Chile and are morphologically distinguished from cystacanths of the 9 other species based on a combination of 4 characters. These are body size, number of proboscis hook rows, number of hooks per row, and length of the largest anterior 2-4 hooks. Male and female cystacanths of P. rancoensis are 2.10-3.33 mm long having an ovoid proboscis with 14 rows of 6-7 hooks per row, with the largest anterior 2-4 hooks being 105-110 micrometers long; the anterior trunk has many small spines in 70-80 concentric rings, each with 50-60 spines around them; hook roots are simple, directed posteriorly, about as long as the blades anteriorly with unremarkable anterior manubria; the cephalic ganglion are in mid-receptacle just anterior to the level of the anterior trunk; the lemnisci are long and slender; the testes are in the anterior trunk, posterior trunk, or one in each; the primordia of 2 tubular cement glands are evident; strong bundles of fibers link the anterior and posterior trunk; and the posterior trunk has a corrugated surface cuticula. Molecular analysis (COI and 18S) sequences coincided with the morphology and support its taxonomy. The phylogenetic profile revealed that P. rancoensis n. sp. fell into the Profilicollis clade. Both sequences showed low genetic variation, and three different haplotypes were found. The new species was more closely related to P. botulus (Van Cleave, 1916) Witenberg, 1932 than to other Profilicollis species.

Title: Révision du concept de Profilicollis Meyer, 1931 avec la description de Profilicollis rancoensis n. sp. (Acanthocephala, Polymorphidae) du crabe d'eau douce Aegla abtao Schmitt, 1942 (Decapoda, Anomura) au Chili, avec une clé des espèces congénères. Abstract: Profilicollis rancoensis n. sp. est la dixième espèce de Profilicollis Meyer, 1931 qui comprend neuf autres espèces principalement connues de crabes décapodes marins et d'oiseaux de rivage. Les cystacanthes de P. rancoensis sont décrits chez le crabe d'eau douce dominant Aegla abtao dans le lac Ranco, au Chili et se distinguent morphologiquement des cystacanthes des neuf autres espèces sur la base d'une combinaison de quatre caractères. Il s'agit de la taille du corps, du nombre de rangées de crochets du proboscis, du nombre de crochets par rangée et de la longueur des 2 à 4 crochets antérieurs les plus grands. Les cystacanthes mâles et femelles de P. rancoensis mesurent de 2,10 à 3,33 mm de long et ont une trompe ovoïde avec 14 rangées de 6 à 7 crochets par rangée, les 2 à 4 crochets antérieurs les plus grands mesurant 105 à 110 micromètres de long ; le tronc antérieur a de nombreuses petites épines en 70-80 anneaux concentriques chacun avec 50-60 épines ; les racines des crochets sont simples, dirigées vers l'arrière, à peu près aussi longues que les lames vers l'avant avec une manubrie antérieure sans particularité ; les ganglions céphaliques sont au milieu du réceptacle juste en avant du niveau du tronc antérieur ; les lemnisques sont longs et minces ; les testicules sont dans le tronc antérieur, le tronc postérieur ou un dans chacun ; les ébauches des 2 glandes cémentaires tubulaires sont évidentes ; de solides faisceaux de fibres relient le tronc antérieur et postérieur ; le tronc postérieur a une cuticule à surface ondulée. Les séquences d'analyse moléculaire (COI et 18S) coïncidaient avec la morphologie et confirmaient sa taxonomie. Le profil phylogénétique a révélé que P. rancoensis n. sp. appartient au clade Profilicollis. Les deux séquences ont montré une faible variation génétique et trois haplotypes différents ont été trouvés. La nouvelle espèce était plus proche de P. botulus (Van Cleave, 1916) Witenberg, 1932 que des autres espèces de Profilicollis.

The elevation of a unique population of Corynosoma strumosum (Acanthocephala: Polymorphidae) from the Caspian seal, Pusa caspica, in the Caspian Sea to Corynosoma neostrumosum n. sp.

An isolated population of 700 specimens initially described as Corynosoma strumosum (Rudolphi, 1802) Lühe, 1904 and currently reassigned to Corynosoma neostrumosum n. sp. was collected from one young male Caspian seal, Pusa caspica (Gmelin) in the southern land-locked Caspian Sea in April 2009. Collected worms were morphologically unique compared with those reported by other observers in open waters, especially in shape and distribution of proboscis hooks and trunk spines, dorso-ventral differences in proboscis hooks and their organization, the baldness of anterior proboscis, consistently smaller size of trunk and testes, larger eggs, the rough egg topography, epidermal micropores, and variations in the female gonopore. Molecular data from the internal transcribed spacer region of rDNA and the mitochondrial cox1 gene was also provided to supplement the morphological study of the new species.

Squamata reptiles as a potential source of helminth infections when preyed on by companion animals.

BACKGROUND: Squamate reptiles cohabiting with companion animals may represent a source of helminth infections, especially through predation by dogs and cats with an outdoor lifestyle. METHODS: In order to assess the role of reptiles as intermediate/paratenic hosts of trophically transmitted helminths, synanthropic reptiles (n = 245) captured from different ecological settings (i.e., households, dog shelters, urban, peri-urban and rural areas or natural parks) of southern Italy were examined for endoparasites. Parasitic cysts (i.e., larval forms of acanthocephalans, cestodes and nematodes) and free helminths (i.e., adult nematodes and digeneans) were morphologically and molecularly identified, and statistical analysis was carried out to evaluate the correlations between reptiles, infections, and ecological settings. RESULTS: Overall, 31% of reptiles were positive for at least one helminth, with Podarcis siculus (18.7%) and Tarentola mauritanica (8.1%) being the most frequently infected species. Among the parasites of medical interest, Joyeuxiella echinorhyncoides showed the highest prevalence (19.7%), followed by Diplopylidium acanthotetra (10.5%), Joyeuxiella pasqualei, Mesocestoides lineatus (5.6%) and Physaloptera sp. (3.9%). Macracanthorhynchus hirudinaceus was detected once. Podarcis siculus and T. mauritanica were associated with cestode infections. CONCLUSIONS: The wide range of helminths detected here in reptiles living in sympatry with pets and the fact that many of these helminth species are parasitic and may infect companion animals (e.g., J. pasqualei, J. echinorhyncoides, D. acanthotetra, Physaloptera sp.) and humans (i.e., Macracanthorhynchus hirudinaceus, Mesocestoides lineatus) indicate the potential health risk associated with pets preying on these small vertebrates. Our results indicate the need for complementary investigations of trophically transmitted parasites in dogs and cats living in sympatry with reptiles.

Helminth community structure of the white-bellied woolly mouse opossum Marmosa constantiae Thomas, 1904 in Central-West Brazil.

Marmosa constantiae is a species of marsupial restricted to the central portion of South America. In Brazil, it occurs in the northwestern region including five states of the Amazon, Cerrado, and Pantanal biomes. However, there is no study of the helminth fauna or helminth community structure for this marsupial. The aims of this study were to describe the species composition and to analyse the structure of the helminthic community of M. constantiae in an area of the Amazon Arc in Sinop, north of the state of Mato Grosso, Brazil. Parasites were searched in 53 specimens of this marsupial, among which 44 were infected with at least one helminth species. Parasitic helminths were counted and identified. Nine species were collected: seven nematodes, one cestode, and one acanthocephalan. The most abundant species were Gracilioxyuris agilisis, Travassostrongylus scheibelorum, Pterygodermatites sinopiensis, and Subulura eliseae. These species were the only dominant ones in the component community. No significant differences were observed in the abundance and prevalence of helminths between male and female hosts. Host body size significantly influenced helminth abundance in males. The pattern of community structure considering the infracommunities in this locality indicated more species replacement than species loss along the environmental gradient. This is the first study to report the helminth fauna and the helminth community structure of M. constantiae.

Survey of intestinal parasites in swine farms raised in Western Nepal.

BACKGROUND: Pigs (Sus scrofa domesticus), an important domestic livestock, are generally affected by helminth and protozoan parasites. Rearing pigs in rural regions in Nepal is a common practice for subsistence farming. A cross-sectional survey was conducted to determine the occurrence of gastrointestinal parasites (GIPs) in pigs raised in Western Nepal. METHODS: A total of 200 faecal samples from commercial and smallholder farms were examined by wet mounts, flotation, sedimentation and staining techniques. RESULTS: The results revealed that overall 86.5% of samples were found shedding oocysts or eggs of one or more GIPs. Three species of protozoa [Eimeria sp. (26%), Entamoeba coli (25.5%) and Coccidia (29%)] and nine species of helminths parasites (Ascaris suum (32.5%), Trichuris suis (30%), strongyle-type nematode (27.5%), hookworm (26%), Fasciola sp. (17.5%), Physaloptera sp. (17.5%), Strongyloides sp. (17.5%), Metastrongylus sp. (8%) and Oesophagostomum sp. (5.5%)] were identified. Female pigs were found to have higher protozoan infection than males, but such a difference was not noticed with regard to helminth parasites. Strongyles and Oesophagostomum infection were higher in commercial farms compared to smallholder farms, whereas the prevalences of E. coli and other protozoans were higher in smallholder farms. Among the contextual factors evaluated for association, weight and gender of pigs, and annual income and gender of managers/caretakers were significantly (p < 0.05) associated with the prevalence of GIPs in pigs. The overall prevalence of certain helminths such as strongyle-type nematode and A. suum was significantly (p < 0.05) associated with the weight of pigs after adjusting other contextual factors. CONCLUSIONS: This study detected relatively high prevalence of intestinal parasites in domestic pig facilities. Molecular epidemiological studies are essential to verify the exact zoonotic potential of parasites carried by pigs in the region. An effective periodic monitoring of GIPs of pigs needs to be carried out to minimize their further dissemination.

A molecular and ecological study of Macracanthorhynchus ingens (von Linstow, 1879) (Acanthocephala: Archiacanthocephala), in its paratenic and definitive hosts in southeastern Mexico and the Eastern USA.

The acanthocephalan Macracanthorhynchus ingens (von Linstow 1879) (Acanthocephala: Archiacanthocephala) is a parasite that infects the gut of carnivores (racoons, coyotes, wolves, foxes, badgers, skunks, opossum, mink and bears) as an adult and the body cavity of lizards, snakes, and frogs as a cystacanth in the Americas. In this study, adults and cystacanths of M. ingens from southeastern Mexico and southern Florida, USA, were identified morphologically by having a cylindrical proboscis armed with 6 rows of hooks each with 6 hooks. Hologenophores were used to sequence the small (SSU) and large (LSU) subunits of ribosomal DNA and cytochrome c oxidase subunit 1 (cox 1) from mitochondrial DNA. Phylogenetic analysis of the new SSU and LSU sequences of M. ingens placed them in a clade with other sequences available in GenBank identified as M. ingens. The cox 1 tree showed that the nine new sequences and six previously published sequences of M. ingens from the USA form a clade with other sequences previously identified as M. ingens from GenBank. The intraspecific genetic divergence among isolates from the Americas ranged from 0 to 2%, and in combination with the phylogenetic trees confirmed that the isolates belonged to the same species. The cox 1 haplotype network inferred with 15 sequences revealed 10 haplotypes separated from each other by a few substitutions. Rio Grande Leopard Frogs and Vaillant´s Frogs harbored cystacanths with low prevalence, 28% and 37% respectively, in Mexico. Brown Basilisks, an invasive lizard in Florida, USA, had high values of prevalence, 92% and 93% in males and females, respectively. Females harbored more cystacanths than males (0-39 vs 0-21) for unknown reasons that may, however, be related to ecological differences.

FIRST RECORD OF A PARASITE, DACTYLOGYRUS CF. SKRJABINI (MONOGENOIDEA: DACTYLOGYRIDAE), INFECTING INVASIVE SILVER CARP, HYPOPHTHALMICHTHYS MOLITRIX (VALENCIENNES, 1844) (CYPRINIFORMES: XENOCYPRIDIDAE) IN NORTH AMERICA.

The parasites infecting invasive carps in North America (all Cypriniformes: Xenocyprididae: grass carp, Ctenopharyngodon idella [Valenciennes, 1844]; silver carp, Hypophthalmichthys molitrix [Valenciennes, 1844]; bighead carp, Hypophthalmichthys nobilis [Richardson, 1845]; and black carp, Mylopharyngodon piceus [Richardson, 1846]) are little studied, and no parasite has been reported from silver carp there. We herein surveyed silver carp from Barkley Reservoir and Cheatham Reservoir (Cumberland River, Tennessee; June and December 2021) and the White River (Arkansas; May 2022) and collected numerous monogenoid specimens infecting the pores on the outer face of the gill raker plate. We heat-killed, formalin-fixed, and routinely stained some specimens for morphology and preserved others in 95% ethanol for DNA extraction and sequencing of the large subunit ribosomal DNA (28S). We identified our specimens as Dactylogyrus cf. skrjabini because they had a dorsal anchor deep root that is much longer than the superficial root, an approximately parallel penis and accessory piece, and a relatively large marginal hook pair V. No type specimen of Dactylogyrus skrjabiniAkhmerov, 1954 (type host and locality is silver carp, Amur River, Russia) is publicly available, but we borrowed several vouchers (NSMT-Pl 6393) that infected the gill rakers of silver carp captured in the Watarase River, Japan. The original description of D. skrjabini was highly stylized and diagrammatical, differing from the specimens we studied from North America and Japan by the dorsal anchor having a superficial root and shaft that comprise a strongly C-shaped hook (the superficial root curves toward the dorsal anchor point) (vs. superficial root straight, at ∼45° angle to deep root and directed away from the dorsal anchor point), a single, much reduced transverse bar that is narrow for its entire breadth (vs. dorsal and ventral transverse bars robust and broad, having an irregular outline), an accessory piece that lacks digitiform projections (vs. accessory piece with 4 digitiform projections), and an accessory piece that lacks a half cardioid-shaped process (vs. accessory piece having a half cardioid-shaped process). Our 28S sequences (generated from 4 specimens of D. cf. skrjabini: 2 from Tennessee [763 base pairs (bp)] and 2 from Arkansas [776 bp]) were identical to 1 ascribed to D. skrjabini from Japan. The present study is the first verifiable and credible report of a parasite from silver carp in North America and the first nucleotide information for a parasite from silver carp in North America.