Worm Species Research Articles

Collecting and Culturing Lineus sanguineus to Study Nemertea WBR.

Whole-body regeneration, the ability to reconstruct complete individuals from small fragments, is rare among ribbon worms (phylum Nemertea) but present in the pilidiophoran species Lineus sanguineus. This species can regenerate complete individuals from a tiny midbody section, and even from a quarter of a piece, provided it retains a fragment of a lateral nerve cord. While a few other unrelated species of ribbon worms are also excellent regenerators, L. sanguineus is unique in having evolved its regenerative abilities quite recently and thus offers an exceptional opportunity to gain insight into the evolutionary mechanisms of regeneration enhancement. Interestingly, both its sister species Lineus lacteus and Lineus pseudolacteus, a third species derived from the recent hybridization of the other two, differ in their regeneration abilities: while L. lacteus is uncapable of regenerating a lost head, L. pseudolacteus is capable of anterior regeneration, albeit at a slower rate than L. sanguineus. L. sanguineus has a worldwide distribution in temperate shores of both hemispheres, is readily found at intertidal habitats, and can survive, feed and be bred through asexual replication with minimal effort in laboratory settings. All the above make this species a superb candidate for studies of regenerative biology. In this chapter, we present protocols to collect, identify and breed L. sanguineus to study the extraordinary whole-body regeneration abilities found in this species.

Evaluation of vegetables grown in dry mountainous regions for soil transmitted helminths contamination.

Infection caused by geo-helminth parasites are called geohelminthiasis are one of the global health problems. Vegetables eaten raw is the principal source of transmission of geo-helminth parasites. Pakistani people believe that eating raw vegetables are a significant source to get important vitamins and minerals. Based on the high incidence of pathogenic parasites and cultivating different vegetable types in the study areas, we conducted this study to evaluate the geo-helminth contamination of raw vegetables in northwest Khyber Pakhtunkhwa, Pakistan. This is a descriptive study comprised, 1942 samples of 25 various types of vegetables. The samples were examined in physiological saline solution using sedimentation and centrifugation methods. The findings were analyzed by Graph-Pad version 5. P value less than 0.05 (95% CI) was considered significant. Results showed that 16.5% (n=322) of all vegetables were contaminated with one or more type of geo-helminth parasites. Garlic was the highest (35%) and cauliflower the lowest (4%) contaminated samples respectively. Ascaris lumbricoides was the most common geo-helminth found followed by hook worm species while Trichuris trichura was the least in all the vegetable samples. Leafy vegetables were highly contaminated 25.3% than vegetables with root parts 21.2% and fruity 9.09%. More than half of the contaminated vegetables were contaminated with single species of geo-helminth (P<0.05) while less than half with multiple types of geo-helminth contamination. Ninety two vegetables samples were contaminated with 2 species of parasites (P<0.05) and 45 with 3 (P>0.05) species of geo-helminth parasites. Education level of vendors and means of display were not significantly associated while types of vegetable used were significantly associated with the prevalence of parasites. The findings of this study provide evidence that consumption of raw vegetable has a high risk of acquiring geo-helminth infections. The authors believe that preventing the human to enter to the vegetable farmland for defecation, avoiding the irrigation of agricultural fields via night soil, and educating the people on proper washing and cooking of vegetables may be useful in reducing parasitic infections.

Паразиты рыб горных озер бассейна Верхней Колымы. 1. Озера большой и малый Дарпир.

The first data on the parasite fauna of fish from the mountain lakes Bolshoy and Maly Darpir at the southern spurs of the Chersky Ridge (Momsky District, Yakutia) are presented. 7 species of fish have been studied, in which 34 species of parasites have been found: 33 species of helminths and 1 species of parasitic copepods, belonging to 22 genera, 16 families, 12 orders, 7 classes of 4 types of the animal kingdom. Trematodes completely dominate by the number of species among helminths (16 species); cestodes are half as many (8 species); these are followed by nematodes and spiny-headed worms (5 and 4 species, respectively). The greatest variety of parasites was found in the East Siberian grayling (22 species) and the Arctic char (19 species). Next to the latter in terms of the number of parasite species, there went the Kolyma sculpin (13 species), round whitefish (10 species each), sucker (9 species), eelpout, and common minnow (7 species each). Only one parasite species, the Neoechinorhynchus salmonis Ching, 1984 spiny-headed worm, is common for all studied fish. The second species of spiny-headed worms, Pseudoechinorhynchus borealis (Linstow, 1901), not found only in the round whitefish, was first recorded in fish of the Okhotsk-Kolyma area and in the sucker as a new definitive host.

The complete mitochondrial genome of the marine feather duster, Bispira melanostigma (Annelida: Sabellidae)

The marine feather duster, Bispira melanostigma (Schmarda, 1861), is a tube-dwelling annelid that contributes to ecological and biogeochemical processes in benthic communities. Due to the lack of scientific data, B. melanostigma is often difficult to distinguish from other species of marine worms through morphological characteristics alone. In this study, we report the complete mitochondrial genome of Bispira melanostigma. The complete mitogenome contained 20,624 bp length with a total of 13 protein-encoding genes, 21 tRNA, and 2 rRNA genes. Phylogenetic analysis of the complete mitochondrial DNA of B.melanostigma can aid in the understanding of evolutionary relationships within Sabellidae.

Deep-sea acorn worms (Enteropneusta) from the Bering Sea with the description of a new genus and a new species of Torquaratoridae dominating soft-bottom communities

Five species of deep-sea acorn worms (Enteropneusta) were found in the Bering Sea during cruises of the RV Akademik M.A. Lavrentyev in 2016, 2018, and 2021. The worms were recorded on slopes of the Volcanologists Massif and in the Komandorsky Graben at depths between 1830 and 4278 m and on the Koryak slope between 419 and 662 m. Four of the species were only photographed but not collected; these were an unidentified Torquaratoridae gen. sp. 1 and three harrimaniids: Saxipendium sp., Harrimaniidae gen. sp. 1 and Harrimaniidae gen. sp. 2. Harrimaniidae gen. sp. 1 and gen. sp. 2 were recorded on the Koryak slope in the vicinity of methane seeps. The fifth species was photographed in situ and collected. It has been examined using morphological and molecular methods. It is described in the present study as Quatuoralisia malakhovi n. gen. n. sp. Ezhova et Lukinykh (fam. Torquaratoridae). The abundance of this species in the soft-sediment community at the depth 1830–2290 m was up to 12 specimens per m2, the highest ever recorded for any deep-sea enteropneusts. Morphologically, Q. malakhovi n. gen. n. sp. is noteworthy for the mesocoel ducts, the heart-kidney complex with a pericardial coelom, the two-plated skeleton supporting the proboscis stalk, and conspicuously elongated lateral wings developed on either side of the trunk. The molecular analysis based on the mitochondrial 16S rRNA showed that Q. malakhovi n. gen. n. sp. is closest to several torquaratorid species that have yet to be formally described morphologically.

Morphology and molecular identification of Eurytrema spp. worm in Aceh cattle, Indonesia

Abstract. Hanafiah M, Helmi TZ, Sutriana A, Bahi M. 2021. Morphology and molecular identification of Eurytrema spp. worm in Aceh cattle, Indonesia. Biodiversitas 22: 5654-5661. The objective of this research was to determine the species of Eurytrema spp. in Aceh cattle which were slaughtered in slaughterhouses located in Banda Aceh, Indonesia. Identification of Eurytrema spp worm species was performed by Semichon’s Carmine staining, SEM and molecular method. The result fromSemichon’s Carmine staining and SEM method showed that worms coded E2 and E3 were Eurytrema cladorchis indicated by clearly visible protruding cirrus while worms coded E1, E4 and E5 were E. pancreaticum indicated by the absence of protruding cirrus. Molecular characterization of Eurytrema spp.produced fragments of approximately 700 bp in length. The phylogenic tree showed that Eurytrema spp.from Aceh cattle consisted of 2 clades: clade 1 was E. pancreaticum, while clade 2 was E. cladorchis. DNA sequencing result showed that the similarity of worm samples coded 1, 4, and 5 were 98.90% similar to E. pancreaticum (KJ767631.1 and KC535543.1), and 96. 33% similar to E. cladorchis (MN566134.5 and MN566140.1), whereas the worm samples coded 2 and 3 were 97.53% similar to E. pancreaticum (KY490000.1 until KY490004.1), and 97.55 % similar to E. cladorchis (MN566135.1 until MN566140.1). This research was able to identify E. pancreaticumand E. cladorchis in Aceh cattle slaughtered in Banda Aceh slaughter houses.

Investigation of fecal egg counts versus worm burden and helminth fauna in cattle treated or not with macrocyclic lactones in a tropical region

Gastrointestinal nematodes negatively impact the health and productivity of livestock. Macrocyclic lactones (MLs) are the most common class of chemicals used in helminth control programs, however, their intense use is accelerating the development of parasite resistance. For cattle, little is known regarding the relationship between fecal egg counts (FECs) and the helminth population inside the animal's gastrointestinal tract and so this study evaluated the correlation between FEC and worm burden in cattle treated or not with MLs (ivermectin 200 μg/kg, ivermectin 630 μg/kg, abamectin 200 μg/kg, doramectin 700 μg/kg and moxidectin 200 μg/kg). Animals were necropsied to determine if there were any modifications to the proportions of worm species due to chemical treatment. FECs of ML-treated and untreated animals showed significant (p ≤ 0.05 and R2 ≥0.70) positive linear correlations and substantial or perfect strength-of-agreement (LCCC ≥ 0.61) with total worms present, all of which were Haemonchus placei and Cooperia punctata. However, this correlation and strength-of-agreement did not occur when the efficacy of MLs was ≥80 % against these helminths. Among the active MLs tested, moxidectin had the weakest relationship between FEC and worm burden, except for H. placei. Analysis of the helminthological fauna found an increase of H. placei (35.6 % = 95 % CI 35.4–35.6) and a consequent decrease of C. punctata (52.5 % = 95 % CI 52.3–52.6) in untreated animals, when compared to studies carried out over 20–40 years ago, but this proportion was reversed for ML-treated animals (C. punctata 64.5 % = 95 % CI 64.4–64.8; H. placei 30.8 % = 95 % CI 30.6–30.8). It is possible that MLs mitigate this effect in the field and that C. punctata remained prevalent in cattle in different regions of Brazil.

Comparative Assessment of the Bioremediation Potential of Polychaetes (Lug worm-Arenicola marina sp and Syllidae Worm-Syllis prolifera sp) in Aquaculture Pond Sediment

Polychaetes play an important role in nutrient cycling and remediation of coastal ecosystems. Large quantities of organic matter that could lead to pollution of pond and coastal waters are generated by aquaculture waste. To assess the remediation prospects of Arenicola marina and Syllis prolifera species, laboratory sediment microcosm experiments were conducted where large size Arenicola marina and Syllis prolifera were introduced to sediment in microcosm A, large size Arenicola marina to sediment in microcosm B, large sized Syllis prolifera to sediment in microcosm C and no polychaetes to sediment in microcosm D. Microcosm A′, B′ and C′ as replicates for small size polychaetes were also set up, respectively. After 30 days, microcosm A, B and C had significant decrease in organic carbon levels with microcosm B being the highest (Total organic carbon (TOC); 27.87%; p&lt; 0.05). Both large and small polychaetes promoted significant decrease in sulphur (S) content (mean=62.76±0.21; 62.81±0.21%) and iron(Fe) (mean=49.43±1.47; 36.28±5.90%) respectively. Increase in pH by 31.15±0.13% was found in the presence of large size polychaetes, most likely associated with the burrowing process involving oxidation of Fe to Fe2O3. Large size polychaetes had better survival (mean=92±0.82%) than their small size counterpart (mean=55±4.08%). The extent of biodegradation B&gt;A&gt;C&gt;D observed revealed that large size Arenicola marina was a better bioremediator of organic matter (OM), Fe and S enriched aquaculture pond sediment, probably due to its biological characteristics, well suited for the aquaculture than other species of sea worms that produce free swimming larvae. Therefore, large size Arenicola marina significantly improved sediment quality as well as increased its pH without compromising their survival. As the search for a better bioremediator of organically enriched sediment continues, our result revealed large size Arenicola marina as a more promising candidate compared to other species documented elsewhere in the world. Hence, rearing of large size Arenicola marina sp is recommended as their feeding habits are well suited for aquaculture.

Intrusion detection system based on bagging with support vector machine

&lt;p&gt;Due to their rapid spread, computer worms perform harmful tasks in networks, posing a security risk; however, existing worm detection algorithms continue to struggle to achieve good performance and the reasons for that are: First, a large amount of irrelevant data affects classification accuracy. Second, individual classifiers do not detect all types of worms effectively. Third, many systems are based on outdated data, making them unsuitable for new worm species. The goal of the study is to use data mining algorithms to detect worms in the network because they have a high ability to detect new types accurately. The proposal is based on the UNSW NB15 dataset and uses a support vector machine to train and test the ensemble bagging algorithm. To detect various types of worms efficiently, the contribution suggests combining correlation and Chi2 feature selection method called Chi2-Corr to select relevant features and using support vector machine (SVM) in the bagging algorithm. The system achieved accuracy reaching 0.998 with Chi2-Corr, and 0.989, 0.992 with correlation and chi-square separately.&lt;/p&gt;

WORM BIOMASS AND VERMICOMPOST PRODUCTION BY THE EPIGEIC EARTHWORM, PERIONYX EXCAVATUS BY USING DIFFERENT ORGANIC WASTES

As the epigeic earthworms are known to be efcient and potential biodegrades and nutrient releasers, tolerant to wide range of ecological disturbances, aids in litter communication and efcient decomposers. Therefore, the present study was undertaken to nd out the inuence of various organic wastes (such as False Ashoka waste-FAW (Polyalthia longifolia), Parthenium wastePW (Parthenium hysterophorus), Cotton residue waste-CRW (Gossypium), Lawn grass waste-LGW (Agrostis) and Cattle manure-CM) on the production of worm biomass and vermicompost by the epigeic earthworm, Perionyx excavatus along with control compost experiments without worms (in triplicates) to know the potentiality of this worm species in processing of various organic wastes for the production of worm biomass as vermiprotein and vermicompost as biofertilizer. Both compost and vermicompost experimental pots were terminated after 35 and 70 days time intervals. Observations were made with respect to number of old and new adult worms, new sub-clitellates, juveniles, cocoons with their weight were noted to determine the total worm biomass (Gross biomass), biomass ratio (WBR) and Fold Increase in Worm Number (FIWN). Percent compost and vermicompost produced out of different organic waste were also calculated at the end of each experiment at35 and 70 days. The results of the present study revealed that the biomass of Perionyx excavatus such as Gross worm biomass (GWB), Worm biomass ratio (WBR) and Fold increase in worm number (FIWN) increased from 35days to 70 days time intervals in all the organic wastes (FAW, PW, CRW, LGW and CM). It was maximum in CM and minimum in FAW among all the organic wastes. There is a signicant variation was noticed in worm biomass production (GWB, WBR, and FIWN) among and between all the organic wastes except between few organic wastes at 35 and 70 days time intervals. The vermicompost production was more as compared to normal compost in all the organic wastes. Further, both compost and vermicompost production were more in CM followed by LGW, CRW, PW and minimum in FAW among all organic wastes. The signicant difference was also observed in the production of compost and vermicompost among and between different organic wastes except between few organic wastes at different time intervals. Based on the results, it can be concluded that the earthworm, Perionyx excavatus is an efcient epigeic earthworm species, effectively used in vermicomposting for the production of vermicompost and as well as in vermifarming in the production of worm biomass as vermiprotein. Further, earthworm biomass, compost and vermicompost production primarily depends on nature of organic wastes and secondly on the potentiality of earthworm species used in the experimental studies.

Muscular adaptations in swimming scale worms (Polynoidae, Annelida).

Annelids are predominantly found along with the seafloor, but over time have colonized a vast diversity of habitats, such as the water column, where different modes of locomotion are necessary. Yet, little is known about their potential muscular adaptation to the continuous swimming behaviour required in the water column. The musculature and motility were examined for five scale worm species of Polynoidae (Aphroditiformia, Annelida) found in shallow waters, deep sea or caves and which exhibit crawling, occasional swimming or continuous swimming, respectively. Their parapodial musculature was reconstructed using microCT and computational three-dimensional analyses, and the muscular functions were interpreted from video recordings of their locomotion. Since most benthic scale worms are able to swim for short distances using body and parapodial muscle movements, suitable musculature for swimming is already present. Our results indicate that rather than rearrangements or addition of muscles, a shift to a pelagic lifestyle is mainly accompanied by structural loss of muscle bundles and density, as well as elongation of extrinsic dorsal and ventral parapodial muscles. Our study documents clear differences in locomotion and musculature among closely related annelids with different lifestyles as well as points to myoanatomical adaptations for accessing the water column.

Emergent Collective Locomotion in an Active Polymer Model of Entangled Worm Blobs

Numerous worm and arthropod species form physically-connected aggregations in which interactions among individuals give rise to emergent macroscale dynamics and functionalities that enhance collective survival. In particular, some aquatic worms such as the California blackworm (Lumbriculus variegatus) entangle their bodies into dense blobs to shield themselves against external stressors and preserve moisture in dry conditions. Motivated by recent experiments revealing emergent locomotion in blackworm blobs, we investigate the collective worm dynamics by modeling each worm as a self-propelled Brownian polymer. Though our model is two-dimensional, compared to real three-dimensional worm blobs, we demonstrate how a simulated blob can collectively traverse temperature gradientsviathe coupling between the active motion and the environment. By performing a systematic parameter sweep over the strength of attractive forces between worms, and the magnitude of their directed self-propulsion, we obtain a rich phase diagram which reveals that effective collective locomotion emerges as a result of finely balancing a tradeoff between these two parameters. Our model brings the physics of active filaments into a new meso- and macroscale context and invites further theoretical investigation into the collective behavior of long, slender, semi-flexible organisms.

Ekstrak Antosianin Dari Ubi Ungu (Ipomoea Batatas L.) Sebagai Pewarna Alami Pada Pemeriksaan Soil Transmitted Helminths (STH) Metode Natif (Direct Slide)

Helminthiasis is a worm infestation caused by several different species of intestinal parasitic worms. This group of worms belongs to the category of Soil Transmitted Helminth (STH) because the process of developing eggs or larvae of these species requires soil to develop into an infective form. The simplest method of examining intestinal nematode worm eggs is the Native Method using 2% Eosin reagent in observing various elements of the examination on the preparations/preparations. Eosin itself has properties that are not easily biodegradable, and generates hazardous waste (toxic) and flammable so that alternative coloring is needed that is more environmentally friendly. Purple sweet potato has a high content of anthocyanin pigments and is more stable than the pigments of strawberries, red cabbage, perilla and other plants. Thus, purple sweet potato has been considered a good source of anthocyanins. This study aims to determine the use of anthocyanin extract from purple sweet potato as a natural dye substitute for eosin dye in the identification of STH in the native method. Parameters observed in the preparations were the quality of visual field contrast, color absorption on the surface of the parasite, and the level of clarity of the appearance of the parasite. The results showed that the use of anthocyanin extract from purple sweet potato at a concentration of 80% could color the eggs of STH worms which were found in positive samples of Ascaris lumbricoides seen in fertile (fertilized eggs) and infertile (unfertilized eggs). Therefore, the anthocyanin extract obtained from purple sweet potato has potential as an alternative dye to replace eosin.

First detection of Colletotrichumfructicola (Ascomycota) on horsehair worms (Nematomorpha).

Fungal members of Colletotrichum (Ascomycota) were found to be associated with Chordodesformosanus, one of the three currently known horsehair worm (Nematomorpha) species in Taiwan. The fungi were identified as Colletotrichumfructicola, which is mostly known as a plant pathogen, through the use of the nuclear ribosomal internal transcribed spacer and partial large subunit (nrITS + nrLSU) and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) DNA sequences. To our knowledge, this report represents both the first records for Colletotrichum associated with hairworms and for fungi on Nematomorpha. These findings expand the knowledge on the ecological relationships of both clades.

Genetic×environment variation in sheep lines bred for divergent resistance to strongyle infection.

Drug‐resistant parasites threaten livestock production. Breeding more resistant hosts could be a sustainable control strategy. Environmental variation linked to animal management practices or to parasite species turnover across farms may however alter the expression of genetic potential. We created sheep lines with high or low resistance to Haemonchus contortus and achieved significant divergence on both phenotypic and genetic scales. We exposed both lines to chronic stress or to the infection by another parasite Trichostrongylus colubriformis, to test for genotype‐by‐environment and genotype‐by‐parasite species interactions respectively. Between‐line divergence remained significant following chronic stress exposure although between‐family variation was found. Significant genotype‐by‐parasite interaction was found although H. contortus‐resistant lambs remained more resistant against T. colubriformis. Growth curves were not altered by the selection process although resistant lambs were lighter after the second round of divergence, before any infection took place. Breeding for resistance is a sustainable strategy but allowance needs to be made for environmental perturbations and worm species.

NEW DEFINITIVE HOST RECORD FOR CHORDODES MORGANI (NEMATOMORPHA) IN NEBRASKA WITH NOTES ON ECOLOGY.

The life cycle and ecology of the horsehair worm Chordodes morgani (Nematomorpha) in Nebraska remain unknown. To identify its definitive host, we installed a series of pitfall traps along 3 first-order streams at 4 sites: Elk Creek, Upper Elk Creek, Maple Creek, and West Oak Creek, all located northwest of Lincoln, Nebraska. In addition, we opportunistically hand-collected insects at these sites, including wood cockroaches (Parcoblatta virginica), and maintained them in the lab until they passed adult worms. Two of these field-collected wood cockroaches each yielded 1 adult worm, which was identified as C. morgani by microscopy, showing that P. virginica serves as a definitive host. Experimental infections of captive-reared Parcoblatta americana supported this result. The wood cockroach was found at all 3 creeks, but C. morgani was not found at West Oak Creek, suggesting that the definitive host does not limit the distribution of C. morgani. Physical properties of the streams were measured to examine how these properties influenced the distribution of the worm. Flow rate and pH differed between the 3 sites where C. morgani was found and the West Oak Creek site, suggesting an important role for these abiotic factors in the distribution of this horsehair worm species.

In addition to birds’ age and outdoor access, the detection method is of high importance to determine the prevalence of gastrointestinal helminths in laying hens kept in alternative husbandry systems

The prevalence of gastrointestinal helminths was investigated in sixty-six commercial non-caged layer flocks. Twenty-nine flocks were housed indoors in aviaries or floor systems, nineteen flocks were kept in conventional free-range systems with outdoor access, and eighteen flocks in organic free-range systems. Flocks were investigated at end of rearing (mean age 17 weeks), peak of egg production (mean age 38 weeks) and before slaughter (mean age 74 weeks). Four different methods were applied to determine worm infestation. During necropsies, worm infestations were recorded and mucosal scrapings were evaluated for the presence of worm eggs. Faecal samples from each flock were investigated by simple flotation method and McMaster counting technique.No gastrointestinal helminths were found in pullets. During production, 87.9 % of the layer flocks were infected with at least one nematode species at the peak of production. The prevalence further increased significantly up to 98.5 % at the end of production (p=0.05). This increase could be ascribed mainly to infections with Ascaridia (A.) galli and/or Heterakis (H.) gallinarum which were most prevalent in all husbandry systems. Furthermore, their prevalence increased significantly with the age of birds (p=0.023; p < 0.001). With regard to the husbandry system, the prevalence of Capillaria spp. was significantly higher in flocks from outdoor systems compared to flocks that were kept indoors. Cestodes were only detected at the end of production with a prevalence of 15.2 % and significantly more flocks with access to outdoor run were found positive. Interestingly, H. gallinarum was found with a high prevalence indoor and in outdoor systems. Anthelminthic treatment did not impact the prevalence of nematode infections. Comparing four different methods for the detection of helminths it was revealed that their efficiencies varied depending on the worm species. Overall, the simple flotation method was superior to detect A. galli and Capillaria spp. This method proved also very efficient for the detection of H. gallinarum but the additional evaluation of the worm infestation during necropsy increased the level of prevalence. Cestodes were mainly found during necropsies when the worm infestation was evaluated. The detection of parasite eggs in mucosal scrapings from the intestines was the least effective method for all helminths. These findings lead to the recommendation to combine faecal investigations with an evaluation of the worm infestation during necropsy of at least five birds.

Ecological analysis of the fish cestode fauna of the mouth of Kura River

The research was conducted in 2014–2019 in the mouth of Kura River. A total of 334 fish specimens of 24 species were examined by the method of full parasitological dissection. As a result, 17 tapeworm species in two orders and eight families were found: Caryophyllaeus fimbriceps, C. laticeps, Caryophyllaeides fennica, Eubothrium acipenserinum, Bothriocephalus acheilognathi, Ligula colymbi, L. intestinalis, Bothriocephalus acheilognathi, Ligula colymbi, L. intestinalis, Proteocephalus filicollis, P. gobiorum, P. ocellata, P. osculatus, Siluritaenia siluri, Gryporhynchus pusillus, and Paradilepis scolecina. Of these, seven species are specific cyprinid parasites, two species are specific sturgeon parasites, two species are specific to sticklebacks, two species to catfish, and one species to gobies; the other three species parasitize in fishes of various families. The main organ of cestode localisation in the studied fishes is the intestinal lumen, where 11 worm species were found. In other fish organs (body cavity, mucous membrane of the anterior intestine, liver, mesentery, and intestinal walls), the number of tapeworm species ranged from one to four. One cestode species invaded from one to seven fish species. In the bream, we found six tapeworm species, while in the other fish species, from one to five. Among the cestodes found, 14 species infect zooplankton-eating fish and only three species (Caryophyllaeus fimbriceps, C. laticeps, Caryophyllaeides fennica) infect fish that feeds on benthic invertebrates. The largest trophic group was the benthophages; they hosted 12 cestode species. In the planktophages and predators, we found eight and seven tapeworm species, respectively. Predatory fishes like pike, asp, round and bighead gobies accumulate parasites from the bodies of their preys, consequently, their cestode fauna is the richest. Most recorded fishes are euryhaline. Nevertheless, due to the absence of typical marine forms among the found cestodes, we registered more tapeworm species in the fish occurring the highly desalinated area of the Kura mouth than in more mineralized water. Six recorded species (Caryophyllaeus fimbriceps, Bothriocephalus acheilognathi, Ligula colymbi, L. intestinalis, Digramma interrupta, and Paradilepis scolecina) are causative agents of fish diseases. Ligula colymbi and L. intestinalis, which have large plerocercoids, caused pathogenic changes in fish organisms. The other pathogenic species did not induce noticeable disorders. They are much smaller, and, thereto, had comparatively low invasion rate in the examined fish.

An epidemiological survey of Dirofilaria spp. and Acanthocheilonema spp. in dogs from the Republic of Moldova

BackgroundDuring the last decades, filarial infections caused by Dirofilaria spp. have spread rapidly within dog populations of several European countries. Increasing scientific interest in filariasis, and the availability of new diagnostic tools, has led to improved knowledge of the biology, morphology, and epidemiology of different species of filarial worms. However, data are still scarce for a number of countries, including the Republic of Moldova. Thus, we assessed the epidemiological status of canine filariasis in the Republic of Moldova to address part of this knowledge gap.MethodsA total of 120 blood samples were collected between June 2018 and July 2019 from dogs originating from the cities of Cahul and Chişinău. The samples were examined microscopically, and multiplex polymerase chain reaction was performed to evaluate filarioid species diversity.ResultsMicroscopic examination revealed that 12 dogs (10.0%) were positive for circulating microfilariae. The molecular test showed that one dog was positive for Acanthocheilonema reconditum (0.8%), one for Dirofilariaimmitis (0.8%), six for Dirofilariarepens (5.0%), and four (3.3%) harboured a co-infection with D. immitis and D. repens. Prevalence was significantly higher in dogs aged ≥ 2 years.ConclusionsThe epidemiological survey presented here for the Republic of Moldova confirmed the presence D. immitis, D. repens and A. reconditum in dogs that had not received any heartworm preventive.Graphical abstract

Scientists from Zoological Museum and Zoological Institute of RAS — researchers of biological diversity and biological resources of the Caspian Sea

The origins of the study of the Caspian Sea date back to the 18th century, when the St. Petersburg Academy of Sciences was founded. The first explorers of the Caspian were academicians P.S. Pallas and S.G. Gmelin. In the 19th century, the study of Caspian fish was continued by K.E. von Baer and O.A. Grimm. Karl von Baer from 1853 to 1857 made four scientific trips to the shores of the Caspian Sea. He pioneered the fundamentals of sustainable fisheries. The main result of the expedition of K.E. von Baer — N.Ya. Danilevsky was the Charter of the Caspian fish and seal fisheries, approved by the government in 1865. According to the results of O.A. Grimm expedition 1874–1876 many new species of worms and crustaceans were discovered and it was found that from 278 species of fish, 150 are found nowhere else. The study of the biodiversity of fish and their parasite fauna in the first half of the last century was continued by scientists of the Zoological Institute N.M. Knipovich, A.N. Svetovidov, A.L. Behning, V.A. Dogel and B.E. Bykhovsky. In 2004, sciemtists of ZIN RAS published the “Catalogue of Agnathans and Fishes of Fresh and Brackish Waters of Russia with comments on nomenclature and taxonomy”, which includes valid names of taxa of agnathans and fish ranging from type to subspecies inhabiting fresh and brackish waters (up to 13 g/l) of the Azov and Caspian Seas and the freshened estuaries of the rivers of the northern and Far Eastern seas (18 orders, 43 families, 175 genera and 486 species). At present, scientists of ZIN RAS continue to study the fish resources of the Caspian Sea.