Search results for " parasite"

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…

Prevalence of bacteria and absence of anisakid parasites in raw and prepared fish and seafood dishes in Spanish restaurants

2015

This study evaluated the presence of bacteria and anisakid parasites in 45 samples of raw anchovies in vinegar, a dish widely eaten in Spain, and in 227 samples of cooked fish and cephalopods served in Spanish food service establishments. Our analysis showed that, according to European and Spanish regulation, 14 to 30% of the prepared fish and cephalopod dishes exceeded the maximum allowable level for mesophilic aerobic counts, and 10 to 40% of these samples exceeded the allowable levels for Enterobacteriaceae. None of the studied samples showed evidence of anisakid parasites, Escherichia coli, Staphylococcus aureus, Salmonella, or Listeria monocyto genes. These results indicate that applic…

IL-23 receptor regulates unconventional IL-17-producing T cells that control bacterial infections.

2010

AbstractIL-23 plays an important role in autoimmune tissue inflammation and induces the generation of not fully characterized effector cells that mediate protection against pathogens. In this paper, we established the essential role of IL-23R in the host response against intracellular pathogens. IL-23 was critical for the expansion or maintenance of γδ and double negative (DN) αβ T cells. These cells were rapidly recruited to the site of infection and produced large amounts of IL-17, IFN-γ, and TNF-α. Notably, DN T cells transferred into L. monocytogenes-infected RAG2−/− mice prevented bacterial growth, confirming their protective role against intracellular pathogens. Our results show that …

From attachment to damage: defined genes of Candida albicans mediate adhesion, invasion and damage during interaction with oral epithelial cells.

2010

Candida albicans frequently causes superficial infections by invading and damaging epithelial cells, but may also cause systemic infections by penetrating through epithelial barriers. C. albicans is an unusual pathogen because it can invade epithelial cells via two distinct mechanisms: induced endocytosis, analogous to facultative intracellular enteropathogenic bacteria, and active penetration, similar to plant pathogenic fungi. Here we investigated the molecular basis of C. albicans epithelial interactions. By systematically assessing the contributions of defined fungal pathways and factors to different stages of epithelial interactions, we provide an expansive portrait of the processes an…

Parasites of Diplodus puntazzo in Western Mediterranean: Morphological, developmental and host-parasite relationships of monogeneans

2014

En España la acuicultura ha experimentado un gran crecimiento durante el pasado siglo, sin embargo, durante los últimos años se ha producido una disminución en la producción de las especies de cultivo más importantes, como la dorada, la lubina y el rodaballo (APROMAR, 2011). Esta situación ha supuesto la primera reducción en la producción de los últimos 25 años. Por este motivo, los productores españoles apuestan por la recuperación de la productividad y el aumento de la competitividad en el mercado y, para poder llevar a cabo estas mejoras, uno de los objetivos marcados es diversificar las especies cultivadas (APROMAR, 2011). En el Mediterráneo español, una de las especies candidatas para …

Connection between temperature, larval production, virulence and geographical distribution of Rhipidocotyle parasites infecting the duck mussel, Anod…

2015

In this thesis, two bucephalid trematode parasites Rhipidocotyle campanula and R. fennica, which use the same first (Anodonta anatina) and second intermediate (Rutilus rutilus) host were studied. The aim was to investigate the effect of temperature on one of the key processes in the transmission of these parasites: 1) the emergence of cercarial larvae from A. anatina over short (1 h) and 2) long (throughout the annual cercarial shedding period, from May to October) time periods as well, as on 3) mussel survival and 4) the seasonal timing of cercarial release. In addition, the aim was to study how the cercarial shedding traits are linked to the 5) geographical occurrence and abundance of the…

Modification of hosts' behavior by a parasite: field evidence for adaptive manipulation.

2007

9 pages; International audience; Parasites relying on trophic transmission to complete their life cycles often induce modifications of their host's behavior in ways that may increase their susceptibility to predation by final hosts. These modifications have often been interpreted as parasite adaptations, but very few studies have demonstrated that host manipulation has fitness benefits for the parasite. The aim of the present study was to address the adaptive significance of parasite manipulation by coupling observations of behavioral manipulation to estimates of trophic transmission to the definitive host in the natural environment. We show that the acanthocephalan parasite Pomphorhynchus …

Gammarids and acanthocephalans, a multi-(cryptic) hosts and multi-parasites system?

2022

Multi-host parasites can exploit various host species that differ in abundance and susceptibility to infection, which will contribute unequally to their transmission and fitness. "Key hosts" are those contributing significantly more to the completion of the life cycle of such parasites. Three non-exclusive criteria may be used to identify a key host: its high abundance, its high exposure/susceptibility to infection, and the large number of infectious stages produced per infected individual. Many parasites with complex life cycles have evolved the ability to manipulate several traits of their intermediate hosts' phenotype, including behavior, thereby increasing the likelihood of transmission…

Modélisation des effets des systèmes de culture sur la dynamique de la plante parasite orobanche rameuse en interaction avec les adventices

2019

Reducing pesticide use is a major challenge in agriculture and involves developing more sustainable methods that rely on non-chemical cropping techniques and biological regulations according to agroecological principles. Branched broomrape (Phelipanche ramosa (L.) Pomel) is a root parasitic plant which infects crops and causes dramatic yield losses worldwide. Managing broomrape is complex because it requires combining several cropping techniques whithin a global weed management strategy because broomrape is also able to infect non-parasitic weeds. The aim of this thesis was to stynthetize knowledge on branched broomrape dynamics in agroecosystems and to aggregate it within a mechanistic mod…