Search results for "Parasite"

Hexamermis sp. an entomopathogenous nematode associated with the European stink bug

2008

The nematodes of the Mermithidae family are a large and important group obligatory parasite of arthropods, principally insects, and are almost always lethal to their hosts. They are usually specific to a single species or to one or two families of them. A mermithid of the genus Hexamermis Steiner, was found parasiting the stink bug Rhaphigaster nebulosa Poda (Hemiptera: Pentatomidae), present on hazelnut plants in the Piedmont region. The bug feeds on various broadleaved woody plant and is considered a serious pest for Mermithidae in Italy. Considerations regarding the taxonomy of the Hexamermis genus are reported. From the taxonomic point of view is very difficult to describe the different…

Vigna mungo, V. radiata and V. unguiculata plants sampled in different agronomical-ecological-climatic regions of India are nodulated by Bradyrhizobi…

2009

International audience; Vigna mungo, Vigna radiata and Vigna unguiculata are important legume crops cultivated in India, but little is known about the genetic resources in native rhizobia that nodulate these species. To identify these bacteria, a core collection of 76 slow-growing isolates was built from root nodules of V. mungo, V. radiata and V. unguiculata plants grown at different sites within three agro-ecological-climatic regions of India. The genetic diversity of the bacterial collection was assessed by restriction fragment length polymorphism (RFLP) analysis of PCR-amplified DNA fragments of the 16S–23S rDNA intergenic spacer (IGS) region, and the symbiotic genes nifH and nodC. One …

Maternal effects in vulnerability to eye-parasites and correlations between behavior and parasitism in juvenile Arctic charr

2017

Hatchery-reared fish show high mortalities after release to the wild environment. Explanations for this include potentially predetermined genetics, behavioral, and physiological acclimation to fish farm environments, and increased vulnerability to predation and parasitism in the wild. We studied vulnerability to Diplostomum spp. parasites (load of eye flukes in the lenses), immune defense (relative spleen size) and antipredator behaviors (approaches toward predator odor, freezing, and swimming activity) in hatchery-reared juvenile Arctic charr (Salvelinus alpinus) using a nested mating design. Fish were exposed to eye-fluke larvae via the incoming water at the hatchery. Fish size was positi…

Outside-host phage therapy as a biological control against environmental infectious diseases

2018

Background Environmentally growing pathogens present an increasing threat for human health, wildlife and food production. Treating the hosts with antibiotics or parasitic bacteriophages fail to eliminate diseases that grow also in the outside-host environment. However, bacteriophages could be utilized to suppress the pathogen population sizes in the outside-host environment in order to prevent disease outbreaks. Here, we introduce a novel epidemiological model to assess how the phage infections of the bacterial pathogens affect epidemiological dynamics of the environmentally growing pathogens. We assess whether the phage therapy in the outside-host environment could be utilized as a biologi…

Resveratrol-induced xenophagy promotes intracellular bacteria clearance in intestinal epithelial cells and macrophages

2019

International audience; Autophagy is a lysosomal degradation process that contributes to host immunity by eliminating invasive pathogens and the modulating inflammatory response. Several infectious and immune disorders are associated with autophagy defects, suggesting that stimulation of autophagy in these diseases should be bene ficial. Here, we show that resveratrol is able to boost xenophagy, a selective form of autophagy that target invasive bacteria. We demonstrated that resveratrol promotes in vitro autophagy-dependent clearance of intracellular bacteria in intestinal epithelial cells and macrophages. These results were validated in vivo using infection in a transgenic GFP-LC3 zebra f…

Corynosoma acanthocephalans in their paratenic fish hosts in the northern Baltic Sea

2003

En 1996-1997, nous avons etudie les stages cystacanthes de trois especes de Corynosoma (Acanthocephala), C. strumosum et C. semerme, ainsi qu'une nouvelle espece C. magdaleni parasite du chabot a quatre cornes (Myoxocephalus quadricornis) dans le golfe de Bothnie. Les longueurs du tronc et du proboscis permettent de differencier les trois especes de parasites. La stabilite temporelle de l'infection par Corynosoma est etudiee en comparant nos resultats a ceux obtenus dans la meme zone geographique centrale et cotiere) en 1977-1982 (Valtonen, 1983a). Comme C. magdaleni et C. strumosum n'etaient pas differenciees a cette epoque, elles ont ete groupees sous l'appellation "C. strumosum" pour les…

Altered host behaviour and brain serotonergic activity caused by acanthocephalans: evidence for specificity

2006

Manipulative parasites can alter the phenotype of intermediate hosts in various ways. However, it is unclear whether such changes are just by-products of infection or adaptive and enhance transmission to the final host. Here, we show that the alteration of serotonergic activity is functionally linked to the alteration of specific behaviour in the amphipodGammarus pulexinfected with acanthocephalan parasites.Pomphorhynchus laevisand, to a lesser extent,Pomphorhynchus tereticollisaltered phototactism, but not geotactism, inG. pulex, whereas the reverse was true forPolymorphus minutus. Serotonin (5-hydroxytryptamine, 5-HT) injected to uninfectedG. pulexmimicked the altered phototactism, but ha…

Effects of feeding diets supplemented with fungus myceliated grains on some production, health and oxidation traits of dairy ewes.

2017

The beneficial properties of mushrooms bioactive compounds indicate their potential use as performance enhancing natural additive for livestock animals. This paper reports the preliminary results of a research on the effects of diets supplemented with fungus myceliated grains (FMG) to lactating ewes in terms of intestinal parasites control, milk production and cheese oxidative stability. During 8 weeks, 21 ewes were divided into 3 groups fed with hay ad libitum and 1.3 kg/day per head of one of 3 concentrates with 0, 10 or 20% of FMG. In front of analogous DM and nutrients intake, the ewes fed FMG at higher levels showed a reduction of intestinal parasite infection, a tendency to improve mi…

2021

Because of its parasitic habits, reproduction costs of the common cuckoo (Cuculus canorus) are mostly spent in pre-laying activities. Female costs are limited to searching host nests and laying eggs, whereas, males spend time in performing intense vocal displays, possibly with territorial purpose. This last aspect, together with a sexual plumage dimorphism, points to both intra- and inter-sexual selections operating within this species. One element triggering sexual selection is a differential fitness accrued by different phenotypes. Before analyzing possible sexual selection mechanisms operating in cuckoos, it is therefore necessary to verify whether there is a variability among male secon…

Sex-specific patterns of antagonistic and mutualistic biotic interactions in dioecious and gynodioecious plants

2013

a b s t r a c t A major transition in flowering plants has been the evolution of separate sexes from hermaphroditism via gynodioecy which is considered to be the most important route. Biotic interactions, both antagonist and mutualistic, have been proposed to influence this transition which is generally accompanied by the evolution of sexual dimorphism in secondary sexual traits. While some researchers have studied sex- specific patterns in herbivory and pollination, less attention has been paid to pathogens/parasites and a limited number of studies have revised sex-specific patterns in mycorrhizal symbiosis. In this article, we explore sex-specific interactions in dioecious and gynodioecio…