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The first description of Setaria tundra (Issaitshikoff & Rajewskaya, 1928) in roe deer from Croatia

Summary

Genus Setaria, Viborg 1795, comprises 46 species that parasitize in the peritoneal cavity of Artiodactyla, Perissodactyla and Hyracoidea. The majority of these infections pass unnoticed, but occasionally they can induce severe peritonitis or neurological signs in aberrant hosts and, rarely, even in humans. In this paper we describe for the first time the finding of Setaria tundra in roe deer in Croatia. We examined 45 roe deer and determined the presence of Setaria nematodes in 24.4% of samples, which were subsequently diagnosed as Setaria tundra using molecular methods.

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First record of Stephanostomum sp. Looss, 1899 (Digenea: Acanthocolpidae) metacercariae parasitising the pleasure oyster Crassostrea corteziensis (Hertlein) from the Mexican Pacific coast

Summary

The aim of this investigation was to identify the parasites present in the largely understudied pleasure oyster Crassostrea corteziensis in Sinaloa state in the northwestern Mexican Pacific coast. Inspection of twenty-eight oysters collected on “Ceuta” lagoon revealed the presence of the digenean Stephanostomum sp. (Digenea: Acanthocolpidae) cysts. Metacercariae were found encapsulated and embedded in the digestive gland and mantle tissue of oysters. The prevalence of infection revealed that 84.6 % were infected, the abundance was 13.62, with a mean intensity of 16.09 per host. The members of this genus are characterized by a double crown of spines in the cephalic region surrounding the buccal opening of the worm. Significantly, we report the first incidence of the digenean Stephanostomum sp of the family Acanthocolpidae parasitizing Crassostrea corteziensis. Further we report that this bivalve is now considered a new intermediate host, and the northwestern Mexican Pacific coast is a new geographical distribution area for this digenean. The findings contribute to our understanding of the biology, biodiversity and host preference of these parasites, with implications for health risks posed by human consumption of the pleasure oyster.

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First report of segmented filamentous bacteria associated with Rhigonema sp. (Nematoda: Rhigonematidae) dwelling in hindgut of Riukiaria sp. (Diplopoda: Xystodesmidae)

Summary

We morphologically and molecularly characterized segmented filamentous bacteria (SFB) associated with Rhigonema sp. nematodes in millipede hindguts. Seventy-three Riukiaria sp. millipedes were collected from a broad-leaf forest in Japan, and nematodes were excised from the millipede’s hindguts. The occurrence rate of SFB associated with nematodes was 24 % (10/41) for males, 47 % (14/30) for females, and 100 % (2/2) for juveniles. Genomic DNA was extracted from four SFB-rich nematode heads, and we obtained 40 bacterial clones via analysis of nearly full-length 16S rDNA gene sequences. At the phylum level, Firmicutes, Proteobacteria, and Verrucomicrobia accounted for 55 %, 40 %, and 5 % of SFB, respectively. In Firmicutes, Clostridiaceae (28 %) and Lachnospiraceae (15 %) were the dominant groups. Our sequences were divided into seven and three subclades between Firmicutes and Proteobacteria in the phylogenetic tree. In the Firmicutes clade, eight sequences were classified as Lachnospiraceae with a bootstrap value >83 %. A phylogenetic tree involving known uncultured Lachnospiraceae sequences characterized the phylogenetic position of SFB associated with nematodes. Our results suggest that the association of SFB with nematode bodies was probably incidental and that SFB are not always present in millipede hindguts. Our bacterial groups corresponded to those of arthropod hindgut, and SFB associated with nematodes were inferred to belong to Lachnospiraceae. Because the Lachnospiraceae sequences obtained in this study showed specific lineages that differed from all the known deposited sequence data, these groups may be unique to Riukiaria sp.

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Forest Management Plan in Domogt Sharyn Gol, Mongolia is Elaborated on Ecological and Sustainable Principles

Abstract

A forest management plan based on ecological principles and forest management sustainability was elaborated for the Domogt Sharyn Gol Company, Mongolia. We presented possibility of use of principles and methods traditionally utilized in forest management planning in the Czech Republic. A used methodology was adjusted for the forestry legislature in Mongolia.

A stratification of site characteristics and the forest development type concept was used as a framework for assessment of a forest property state via an operational forest inventory. A randomly generalized network of 354 inventory plots on the total area of 3 194 ha with spacing of 300 × 300 m was established for measurements of tree species, natural regeneration and a volume of lying deadwood.

We produced a text, table, graph, figure and map material consisted of areal, tree species and wood volume structuring including calculation of decenal logging, thinning treatments, plantation activities and natural regeneration support.

This forest management plan provides a feasible perspective not only towards immediate commercial benefits but also towards sustainability of forest yield and other ecological forest functions. This way of management planning is also a save way towards mitigation of current environmental issues in a Mongolian forest landscape.

Open access
Geospatial Approach for Quantitative Drainage Morphometric Analysis of Varuna River Basin, India

Abstract

An assessment of Varuna river basin of India was performed to study the various drainage parameters in GIS platform. The delineation of drainage network is possible either physically from topographic sheets or with the help data of Digital Elevation Model (DEM) by methods for calculation techniques. Extraction of the basin and sub-basins, stream network has been produced to evaluate the drainage characteristics in the study zone. The entire Varuna river basin has been subdivided into 3 sub-watersheds and 41 morphometric parameters have been computed under four broad categories i.e. drainage network, basin geometry, drainage texture, and relief characteristics. The morphometric analysis has been performed and different parameters have been correlated with each other to understand their underlying connection and their role over the basin hydro geomorphology. The study discloses different types of morphometric analysis and how they influence the soil and topography of the basin. The investigation and estimation of basin morphometry and relief parameters in GIS will be of massive utility in catchment area advancement, understanding the watershed for natural resource evaluation, planning and administration at any scale. The outcomes thus generated equip us with significant knowledge and may also provide an input that are essential in decision making for watershed planning and drainage development of the watershed.

Open access
A geospatial approach to flash flood hazard mapping in the city of Warangal, Telangana, India

Abstract

Dense urbanization leading to uncontrolled transformations within settlements result in flash flooding with overflowing drains leading to a greater inconvenience for the public and damage to private properties. Hence mapping of flash floods would be useful in identifying the high-risk flood zones for disaster response and urban services, during emergencies with rainfall events of high intensity. This article aims to prepare a flood hazard map of Warangal Municipal Corporation (WMC) in Telangana State, India. WMC is chronically affected due to a rise in water levels resulting in flash floods, with an increase in encroachments. The factors considered in this study are rainfall (curve number), surface slope and surface roughness, type of soil, and distance to main channel, drainage density, and land use cover. To decide the relative weight of the impact of each flood causative factors an Analytical Hierarchical Process (AHP) was used. Accordingly, a composite Flood Hazard Index (FHI) has been derived by using the multiple-criteria decision-making tools by integrating these into a Geographical Information System (GIS). The Soil and Water Assessment Tool (SWAT) in Quantum GIS (QGIS), which is a hydrological model, was used to evaluate the projection of streamflow over the water basin and model parameters were optimized using water balance equations during calibration and validation periods.

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Helminths of the Eurasian marsh frog, Pelophylax ridibundus (Pallas, 1771) (Anura: Ranidae), from the Shiraz region, southwestern Iran

Summary

Fourty seven specimens of Pelophylax ridibundus were collected in the vicinity of Shiraz, Fars Province, Iran in 1972. Fourteen helminth species were found, eight digeneans (Diplodiscus subclavatus, Halipegus alhaussaini, Haematoloechus similis, Codonocephalus urniger, and four species of metacercariae) and 6 nematodes (Cosmocerca ornata, Rhabdias bufonis, Abbreviata sp., Eustrongylides sp., Onchocercidae gen. sp. and one species of larval nematodes). Of these, only six are adults, while 8 are in their larval stage. The most prevalent helminths were the metacercariae of Codonocephalus urniger (61.7%) and the larvae Abbreviata sp. (55.32%). The adults with the highest prevalence are the digenean Halipegus alhaussaini, and the nematode Cosmocerca ornata (34% in both cases).

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Human dirofilariasis in Bulgaria between 2009 and 2018

Summary

Autochthonous Dirofilaria repens infections have been found in dogs and other carnivores in most European countries. In the same countries, reports of human dirofilariasis are becoming increasingly prevalent. We present 18 cases of people infected with D. repens for a 10-year period traced in our hospital. The data was collected from the observations and tests of all 18 patients from the whole country treated at the Specialized Hospital for Infectious and Parasitic Diseases in Sofia in the period 2009 – 2018. We used a morphological method, serology test and Knott’s method for microfilariae. The patients were 11 to 74 years of age, 12 female and 6 male. In most cases, patients have subcutaneous nodules or face, eyelid and eyes localization. The trend of increasing incidence in Bulgaria continues, with age and sex distribution and localization of the larva being similar to those in other European countries.

Open access
The impact of acids approved for use in foods on the vitality of Haemonchus contortus and Strongyloides papillosus (Nematoda) larvae

Summary

The laboratory experiment described in this article evaluated the death rate of larvae of Haemonchus contortus (Rudolphi, 1803) nematodes of the Strongylida order and Strongyloides papillosus (Wedl, 1856) of the Rhabditida order under the impact of different concentrations of 8 flavouring acids and source materials approved for use in and on foods and in medicine (formic, wine, benzoic, salicylic, stearic, kojic, aminoacetic, succinic acids). Minimum LD50 for third stage larvae of (L3) S. papillosus was observed with salicylic and wine acids, for L3 H. contortus larvae – with formic acid. Minimum impact on all studied stages of development of nematodes was caused by stearic, kojic, aminoacetic and succinic acids: larvae did not die in the course of one day even at 1 % concentration of these substances. The best parameters of LD50 were observed for benzoic and formic acid. Further experiments on flavouring acids and source materials approved for use in and on foods and in medicines, and also their compounds, will contribute to developing preparations with a stronger impact on nematode larvae – parasites of the digestive tract of vertebrate animals and humans.

Open access
The impact of tourism on local communities and their environment in Gilgit Baltistan, Pakistan: a local community perspective

Abstract

The northern area of Pakistan, Gilgit Baltistan (GB), has huge tourist potential due to its exotic mountain beauty. According to the GB Tourism Department, a large number of tourists (around 200651) visit GB every year from across the country. Due to a large influx of tourists in the area both positive and negative impacts have been felt especially on the environment and on the local communities. The environmental impacts of tourism were investigated in this research in two districts of GB. Three villages were selected from each of the districts of Hunza and Diamer as the basis of this research. This study was based on the perceptions and attitudes of the respondents. The total number of questionnaires completed was 340 filled from different respondent categories. Results showed that deforestation, loss of biodiversity, generation of solid waste, water, air and noise pollution, damage cultural and heritage sites and are the main environmental issues caused by tourism activities in the villages in these districts. About 42% of respondents said that deforestation and loss of biodiversity were high in the Diamer district while in Hunza 39% of respondents said that solid waste generation was high. Similarly, 21% respondents in Hunza and 14% respondents in Diamer agreed that water pollution is caused by tourism activities. Microbial analysis of water confirmed the presence of Salmonella typhi, E. coli and Enterobacter sp. There were positive impacts of tourism with results revealing that 87% of villagers and 98% of businessmen responded that tourism had provided them with jobs and business during the peak tourism season. Hotels and restaurants are the main source of jobs in GB mainly as porters and guides. According to the data collected dry fruits, medicinal herbs, gemstones and handicrafts provided considerable attractions for tourists. It is recommended that a combined effort be made by the local communities, tourism departments and other Govt. Agencies to ensure the cleanliness of tourist attractions.

Open access