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Omar M. Amin

Abstract

The respectable community of parasitologists aimed at the broad-spectral research of acanthocephalan parasites met at the 9th Acanthocephalan Workshop. The workshop took place in the beautiful surroundings of the High Tatras, Slovakia in the Congress Centre Academia, Stará Lesná near Tatranská Lomnica on September 9 - 13th. This special event was hosted by the Slovak Society for Parasitology, the Institute of Parasitology of the Slovak Academy of Sciences, Košice, Slovakia, and the Czech University of Life Sciences Prague, Czech Republic. It consisted of nearly three dozen lectures presented by distinguished acanthocephalan specialists who came from 13 countries and five continents. Vibrant discussions and creating new plans for future collaborations were accompanied by local mountain touring that offered the venue richly endowed with nature, deep forests and beautiful mountains. The contributions were addressed to resolve current systematic, taxonomic, biological, behavioural, ecological, and related topics. Presented results showed the most recent progressive developments comparable with all the other parasitic worm groups. The 10th Acanthocephalan Workshop will be hosted by Dr. Marie-Jeanne Perrot-Minnot, Université de Bourgogne Franche-Comté, Dijon, Bourgogne, France, in 2022.

Open access

C. Hu, X. G. Xia, X. M. Han, Y. F. Chen, Y. Qiao, D. H. Liu and S. L. Li

Abstract

To study the effect of fertilization on soil nematode communities in a paddy-upland rotation system, an ongoing thirty-three years long-term fertilizer experiment is conducted which includes seven treatments; an unfertilized treatment (control), nitrogen (N), phosphorus (P), potassium (K) fertilizer treatments (N, NP, NPK) and organic manure (M) combined with chemical fertilizer treatments (MN, MNP, and MNPK). The soil nematode community structure and crop yields were determined in 2012 and 2013. Overall total nematode abundance was increased by an incremental nutrient input both in the rice and wheat fields. Total number of nematode was 1.25 - 2.37 times greater in the rice field and was 1.08 - 2.97 times greater in wheat field in the fertilization treatments than in the unfertilized treatment. Soil free-living nematode abundances was significantly (P < 0.001) increased in organic manure combined with chemical fertilizer treatments in rice field. Fungi-feeders and plant-feeding nematodes abundances were not significantly different among treatments in rice and wheat fields. Omnivorous and predatory nematodes were the most dominant groups in the present study. Omnivores, predators and Prodorylaimus abundances were significantly (P < 0.05) higher in organic manure combined with NPK fertilizer treatments than in chemical fertilizer alone and unfertilized treatments both in rice and wheat fields. Stepwise regressions revealed that soil free-living nematodes were significant predictors of rice grain yields (R2 = 0.56, P < 0.001) and omnivorous and predatory nematodes were significant predictors of the wheat grain yield (R2 = 0.89, P < 0.001). Therefore, long-term application of organic manure combined with chemical fertilizer could increase nematode abundances and crop yields. Organic manure combined with chemical fertilizer application was recommended in agricultural ecosystem.

Open access

K. Apiwong, Ch. Wongsawad and P. Butboonchoo

Abstract

Cyprinoid fish in Chiang Mai province has been reported the presence of a large number of metacercariae, particularly the metacercariae of Haplorchoides and those not identified to species. This study aims to investigate morphological and molecular characteristic of the minute intestinal fluke H. mehrai metacercariae in two cyprinoid fish species from Chom Thong district, Chiang Mai province, Thailand: the Tinfoil barb (Barbonymus schwanenfeldii) and the White eye barb (Cyclocheilichthys repasson). A total of 180 fish (90 from B. schwanenfeldii and 90 from C. repasson) were collected over three seasons: cool, hot and the rainy season (December 2015 to August 2016). Fish were examined for H. mehrai metacercariae infection, including areas such as muscle and the inner side of body scales, by using a light microscope. The prevalence of H. mehrai metacercariae in B. schwanenfeldii and C. repasson was 73.33 % and 100 % respectively. Haplorchoides metacercariae were identified as H. mehrai based on the morphological characteristics; the position of the acetabulum and the number and arrangement of the acetabular spines. Phylogenetic analysis based on Cytochrome c Oxidase subunit I (COI) gene showed that H. mehrai metacercariae from B. schwanenfeldii and C. repasson were the same species as the adult stage of H. mehrai from Hemibagrus nemurus and Mystus multiradiatus. Both morphological and molecular characteristic could indicate that Haplorchoides metacercariae originated from this study were H. mehrai. Furthermore, it is a new record of the minute intestinal fluke Haplorchoides mehrai in Chiang Mai Province

Open access

D. Chagas De Souza, L. Lima Correa and M. Tavares-Dias

Abstract

The present study investigated the occurrence of metacercariae of Ithyoclinostomum dimorphum in Hoplias malabaricus in the basin of the São Francisco River in the state of Minas Gerais (Brazil). Twenty-nine fish were examined in June 2012 during a survey of fish and parasitic fauna. Of the fish examined, 34.5 % had infected eyes, intestine and musculature, with a mean intensity of 1.1 and an abundance of 0.4 per fish. The prevalence in the intestine was 31.0 %, with mean intensity of 1.1 and mean abundance of 0.3. In the eyes, the prevalence was 3.4 %, with a mean intensity of 1.0 and mean abundance of 1.0. The metacercaria found in the right eyeball was lodged between the cornea and iris. The low parasitism did not affect the condition factor (Kn) of the parasitized fish. This was the first report of I. dimorphum in the eyes of Hoplias malabaricus, a secondary intermediate host for this endoparasite.

Open access

A. Dudlová, P. Juriš, P. Jarčuška, Z. Vasilková, V. Vargová, M. Sumková and V. Krčméry

Abstract

Helminth infections caused by Enterobius vermicularis have a cosmopolitan character and most often affect the paediatric pre-school and school age population. The presented study was conducted to determine the prevalence of E. vermicularis in the analyzed population of children in the Eastern Slovakia. The Graham’s scotch tape method was used to investigate the presence of Enterobius vermicularis eggs in 390 specimens. The analyzed set consisted of 218 girls and 172 boys, divided by age into three groups - aged from 5 months to 2 years, aged from 3 to 6 years, and aged from 7 to 15 years. Investigation of perianal scotch tapes of children for the presence of E. vermicularis eggs revealed the prevalence of E. vermicularis was P = 3.59 %. Depending on the incidence of E. vermicularis infection, we detected no statistically signifi cant difference (p> 0.05). The prevalence of E. vermicularis in boys was P = 4.07 %, and in girls P = 3.21 %. The highest prevalence of E. vermicularis was recorded in the group of children aged from 3 to 6 years (P = 5.03 %). Most of the samples were positive at age 4 and 5. The lowest prevalence was in the group of children aged from 5 months to 2 years (P = 0.97 %), and the prevalence of E. vermicularis in the group of children aged from 7 to 15 was P = 3.91 %. The difference in the incidence of E. vermicularis infection among different age groups of children was not statistically significant (p> 0.05). Enterobius vermicularis nematode infection and enterobiasis currently represents a major public health problem in Slovakia. At the present its occurrence is the most frequent in the paediatric population. Therefore it is important to introduce a targeted hygienic-epidemiological measure in children’s collectives, what also should include proper and effective diagnostics and frequent recurrent therapy.

Open access

E. F. Fernandes De Carvalho, A. Ferreira Da Silva-Neta, C. De Sousa Silva, C. R. De Oliveira, J. Da Cunha Xavier Nunes, T. Gonçalves De Souza and R. W. Ávila

Abstract

Snakes have diverse feeding and living habits, being exposed to a variety of endoparasite communities. However, more studies are still necessary to document these relationships. We examined 18 specimens of the cat-eyed snake Leptodeira annulata from a semi-arid region in Northeast Brazil. Eight taxa of parasites were found, with higher prevalence of cystacanths (Acanthocephala). Five nematode species (Hexametra boddaertii, Oswaldocruzia sp., Oxyascaris sp., Physaloptera sp. and Raillietnema spectans) and the pentastome Raillietiella furcocerca represent a new parasitism record for the host studied. Our results also showed that L. annulata could act as paratenic host for acanthocephalans. These results contribute to the knowledge of the helminth fauna of L. annulata.

Open access

A. A. M. Teixeira, R. J. Silva, S. V. Brito, D. A. Teles, J. A. Araujo-Filho, L. D. Franzini, D. O. Santana, W. O. Almeida and D. O. Mesquita

Abstract

We analyzed the patterns of infection by helminths in populations of the Gymnophthalmidae lizard Dryadosaura nordestina from three Atlantic Forest fragments in Northeast Brazil. Prevalence and mean intensity of infection by location showed the following results: ARIE Mata de Goiamunduba (60.8 % and 10.4 ± 8), RPPN Engenho Gargaú (83.3 % and 20.8 ± 19.7) and Benjamim Maranhão Botanical Garden (70.4 % and 7.78 ± 5.8). We provide the first records of helminth infection for the lizard D. nordestina, in which three species of nematodes, Aplectana sp., Cosmocerca sp. and Physaloptera lutzi and one trematode Haplometroides odhneri were recovered. Trematodes of the genus Haplometroides were previously known as parasites only in snake and amphisbaenian hosts in South America. Now, our study provides the first record of a species belonging to this genus parasitizing lizards. In conclusion, our study shows that D. nordestina have a depleted helminth fauna (three species at maximum), similar to other studies with lizards of this family in Brazil and that its parasite abundance is related to host snout-vent length, but not to the sex.

Open access

C. De S. Silva, R. W. Ávila and D. H. Morais

Abstract

Climatic variation in low latitudes influences the dynamics and structure of parasite communities. Environmental changes caused by dry and rainy seasons alter prevalence and abundance of endoparasite communities. In addition to providing a list of the helminth species associated with the swamp frog Pseudopaludicola pocoto, this study aimed to investigate the effects of rainfall and temperature on parasitological descriptors of helminths associated with P. pocoto in an area of the semiarid zone. A total of 817 swamp frog specimens were collected between 2013 and 2017, with four sampling expeditions during the dry season and four during the rainy season. Environmental parameters of temperature and rainfall were compared to the parasitological descriptors of prevalence, abundance and mean infection intensity of the parasite community using a multivariate linear regression. A richness of eight parasite species was identified, including Nematoda (Rhabdias sp., Cosmocerca parva, Oxyascaris oxyascaris, Physaloptera sp., Brevimulticaecum sp., Spiroxys sp. and unidentified nematode) and Acanthocephala (cystacanths). Rainfall levels had a significant effect on the infection intensity of Rhabdias sp. being the presence of this species higher during the rainy season, whereas no influence of temperature was observed on the helminth community.

Open access

M. Pravdová, M. Ondračková, I. Přikrylová, R. Blažek, Z. Mahmoud and M. Gelnar

Abstract

Dactylogyrid monogeneans of Labeo horie Heckel, 1847 and L. niloticus (Linnaeus, 1758) (Cyprinidae) were surveyed at two sites on the River Nile in Sudan. The present study reports the presence of ten species of Dactylogyrus Diesing, 1850 and three species of Dogielius Bychowsky, 1936 based on a morphometric evaluation of the sclerotised structures. The species found include: Dactylogyrus nathaliae Guégan, Lambert & Euzet, 1988; D. rastellus Guégan, Lambert & Euzet, 1988; D. retroversus Guégan, Lambert & Euzet, 1988; D. senegalensis Paperna, 1969, D. yassensis Musilová, Řehulková & Gelnar, 2009 and five other undescribed species of Dactylogyrus. The genus Dogielius was represented by Dogielius flosculus Guégan, Lambert & Euzet, 1989; the newly identified D. sennarensis n. sp., and one undescribed Dogielius species. While D. sennarensis n. sp. resembles D. intorquens, it differs from this species and other congeners by having a longer ventral bar and anchor points and nosclerotised vagina. In addition, this study redescribes D. flosculus based on the morphology of specimens collected from L. horie. All specimens studied had a single large vagina, in contrast to the original description which reported a vagina composed of two unconnected parts. All dactylogyrid species in this study represent new host and geographical records.