The role of season, habitat, host age, and sex on gill parasites of Ambloplites rupestris (Raf.)

One thousand and forty-five rock bass (Ambloplites rupestis (Raf.)) were collected from May 1970 through October 1972 from the Bay of Quinte, Ontario. During the same sampling period, 1043 specimens of the same host were collected from West Lake, Prince Edward County, Ontario.Data were collected on three groups of gill parasites, Monogenea (four species), Copepoda (three species), and glochidia (one species). The data, treated synecologically, were analysed using a two-factor ANOVA and Duncan's multiple range test. The roles of season, habitat, host age, and sex on parasite load were analysed.Host sex was found to have no effect on the three groups of parasites. The abundance of parasites increased with host age (P < 0.001). A marked seasonal effect was noted for all three groups of parasites (P < 0.001). A eutrophic habitat, West Lake, was found significantly more favourable (P < 0.001) for Monogenea, while an oligotrophic habitat, Glenora, was clearly more favourable (P < 0.001) for Copepoda.

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The role of season, habitat, host age, and sex on gill parasites of Lepomis gibbosus (L.)

Canadian Journal of Zoology ◽

10.1139/z78-178 ◽

1978 ◽

Vol 56 (6) ◽

pp. 1247-1250 ◽

Cited By ~ 24

Author(s):

George Hanek ◽

C. H. Fernando

Keyword(s):

Sampling Period ◽

Parasite Load ◽

Seasonal Effect ◽

Lepomis Gibbosus ◽

Host Age ◽

West Lake ◽

Prince Edward County ◽

Host Sex ◽

Gill Parasites ◽

Age And Sex

One thousand and forty pumpkinseeds (Lepomis gibbosus (L.)) were collected from May 1970 through October 1972 from the Bay of Quinte, Ontario. Also, 1018 specimens of the same host were collected during the same sampling period from West Lake, Prince Edward County, Ontario.Data were collected on three groups of gill parasites, Monogenea (seven species), Copepoda (three species), and glochidia (one species). The data, treated synecologically, were analysed using a two-factor ANOVA and Duncan's multiple range test. The roles of season, habitat, host age, and sex on parasite load were analysed. Host sex was found to have no effect on the three groups of parasites. The abundance of parasites increased with host age (P < 0.001). A marked seasonal effect was noted for all three groups of parasites (P < 0.001), all three being most abundant during the summer period. A eutrophic habitat, West Lake, was found significantly more favourable (P < 0.001) for all three parasitic groups.

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Seasonal dynamics and spatial distribution of Cleidodiscus stentor Mueller 1937 and Ergasilus centrarchidarum Wright 1882, gill parasites of Ambloplites rupestris (Raf.)

Canadian Journal of Zoology ◽

10.1139/z78-177 ◽

1978 ◽

Vol 56 (6) ◽

pp. 1244-1246 ◽

Cited By ~ 5

Author(s):

George Hanek ◽

C. H. Fernando

Keyword(s):

Spatial Distribution ◽

Seasonal Dynamics ◽

Gill Arch ◽

West Lake ◽

Clear Preference ◽

Anterior Side ◽

Gill Parasites ◽

Ambloplites Rupestris

Seasonal dynamics and spatial distribution were determined for Cleidodiscus stentor Mueller 1937 and Ergasilus centrarchidarum Wright 1822, gill parasites of Ambloplites rupestris (Raf.).Twenty-five specimens of A. rupestris from eutrophic (West Lake) and 25 specimens from oligotrophic (Glenora) habitats were examined monthly between November 1971 and October 1972.The data were analysed using a two-factor ANOVA and Duncan's multiple range test.High abundance levels of C. stentor and E. centrarchidarum were recorded in the two localities throughout the sampling period.Cleidodiscus stentor, the dominant parasite of A. rupestris in West Lake, reached the peak during March 1972 in West Lake and during April 1972 in Glenora. Ergasilus centrarchidarum, the dominant parasite of A. rupestris in Glenora, reached the peak during August 1972 in both localities.The anterior side of hemibranchs, their medial sections, and gill arch two were preferred sites of infection (P < 0.001) for C. stentor.Ergasilus centrarchidarum exhibited clear preference (P < 0.001) for anterior sides of hemibranchs and their dorsal and ventral sections, while its distribution over the four gill arches was fairly even.

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Intra-Colonial Viral Infections in Western Honey Bees (Apis mellifera)

Microorganisms ◽

10.3390/microorganisms9051087 ◽

2021 ◽

Vol 9 (5) ◽

pp. 1087

Author(s):

Loreley Castelli ◽

María Laura Genchi García ◽

Anne Dalmon ◽

Daniela Arredondo ◽

Karina Antúnez ◽

...

Keyword(s):

Apis Mellifera ◽

Honey Bee ◽

Viral Infections ◽

Sampling Period ◽

Virus Genome ◽

The Individual ◽

Bee Virus ◽

Insight Into ◽

Bee Viruses

RNA viruses play a significant role in the current high losses of pollinators. Although many studies have focused on the epidemiology of western honey bee (Apis mellifera) viruses at the colony level, the dynamics of virus infection within colonies remains poorly explored. In this study, the two main variants of the ubiquitous honey bee virus DWV as well as three major honey bee viruses (SBV, ABPV and BQCV) were analyzed from Varroa-destructor-parasitized pupae. More precisely, RT-qPCR was used to quantify and compare virus genome copies across honey bee pupae at the individual and subfamily levels (i.e., patrilines, sharing the same mother queen but with different drones as fathers). Additionally, virus genome copies were compared in cells parasitized by reproducing and non-reproducing mite foundresses to assess the role of this vector. Only DWV was detected in the samples, and the two variants of this virus significantly differed when comparing the sampling period, colonies and patrilines. Moreover, DWV-A and DWV-B exhibited different infection patterns, reflecting contrasting dynamics. Altogether, these results provide new insight into honey bee diseases and stress the need for more studies about the mechanisms of intra-colonial disease variation in social insects.

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Calibrating the CreditRisk+ Model at Different Time Scales and in Presence of Temporal Autocorrelation †

Mathematics ◽

10.3390/math9141679 ◽

2021 ◽

Vol 9 (14) ◽

pp. 1679

Author(s):

Jacopo Giacomelli ◽

Luca Passalacqua

Keyword(s):

Time Series ◽

Default Risk ◽

Real Life ◽

Statistical Error ◽

Real Data ◽

Sampling Period ◽

Calibration Procedure ◽

Industry Standards ◽

Default Rate

The CreditRisk+ model is one of the industry standards for the valuation of default risk in credit loans portfolios. The calibration of CreditRisk+ requires, inter alia, the specification of the parameters describing the structure of dependence among default events. This work addresses the calibration of these parameters. In particular, we study the dependence of the calibration procedure on the sampling period of the default rate time series, that might be different from the time horizon onto which the model is used for forecasting, as it is often the case in real life applications. The case of autocorrelated time series and the role of the statistical error as a function of the time series period are also discussed. The findings of the proposed calibration technique are illustrated with the support of an application to real data.

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Absence of Bim sensitizes mice to experimental Trypanosoma cruzi infection

Cell Death and Disease ◽

10.1038/s41419-021-03964-6 ◽

2021 ◽

Vol 12 (7) ◽

Author(s):

Marcela Hernández-Torres ◽

Rogério Silva do Nascimento ◽

Monica Cardozo Rebouças ◽

Alexandra Cassado ◽

Kely Catarine Matteucci ◽

...

Keyword(s):

T Cells ◽

Trypanosoma Cruzi ◽

Chagas Disease ◽

Parasite Load ◽

Peritoneal Macrophages ◽

T Cell Response ◽

No Production ◽

Similar Reduction ◽

Ifn Γ

AbstractChagas disease is a life-threatening disorder caused by the protozoan parasite Trypanosoma cruzi. Parasite-specific antibodies, CD8+ T cells, as well as IFN-γ and nitric oxide (NO) are key elements of the adaptive and innate immunity against the extracellular and intracellular forms of the parasite. Bim is a potent pro-apoptotic member of the Bcl-2 family implicated in different aspects of the immune regulation, such as negative selection of self-reactive thymocytes and elimination of antigen-specific T cells at the end of an immune response. Interestingly, the role of Bim during infections remains largely unidentified. To explore the role of Bim in Chagas disease, we infected WT, Bim+/−, Bim−/− mice with trypomastigotes forms of the Y strain of T. cruzi. Strikingly, our data revealed that Bim−/− mice exhibit a delay in the development of parasitemia followed by a deficiency in the control of parasite load in the bloodstream and a decreased survival compared to WT and Bim+/− mice. At the peak of parasitemia, peritoneal macrophages of Bim−/− mice exhibit decreased NO production, which correlated with a decrease in the pro-inflammatory Small Peritoneal Macrophage (SPM) subset. A similar reduction in NO secretion, as well as in the pro-inflammatory cytokines IFN-γ and IL-6, was also observed in Bim−/− splenocytes. Moreover, an impaired anti-T. cruzi CD8+ T-cell response was found in Bim−/− mice at this time point. Taken together, our results suggest that these alterations may contribute to the establishment of a delayed yet enlarged parasitic load observed at day 9 after infection of Bim−/− mice and place Bim as an important protein in the control of T. cruzi infections.

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Carotenoid-based plumage colouration in red bishops (Euplectes orix) — signalling presence rather than quality?

Behaviour ◽

10.1163/000579511x608693 ◽

2011 ◽

Vol 148 (11-13) ◽

pp. 1372-1392 ◽

Cited By ~ 3

Author(s):

Alice U. Edler ◽

Thomas W.P. Friedl

Keyword(s):

Reproductive Success ◽

Parasite Load ◽

Blood Parasite ◽

Male Reproductive Success ◽

Sexually Dimorphic ◽

Male Quality ◽

Plumage Colouration ◽

Selection For ◽

Breeding Plumage

AbstractThe role of bright plumage colouration for female choice has been the focus of research in sexual selection for many years, with several studies showing that females prefer the most elaborately ornamented males, which are often also the highest quality individuals. Here, we analysed the associations between reproductive performance and plumage, body condition and blood parasite load in the red bishop (Euplectes orix), a sexually dimorphic and polygynous weaverbird species, where males in a carotenoid-based orange-to-red breeding plumage defend territories and build many nests to which they try to attract females. Male reproductive success in terms of number of nests accepted was mainly determined by the number of nests built, but was also positively related to blood parasite load, while we found no influence of plumage characteristics. Together with previously obtained data, our results indicate that plumage characteristics in the red bishop do not affect male reproductive success and are generally not suitable to reliably indicate male quality. We suggest that the primary function of the brilliant orange-scarlet breeding plumage might be presence signalling in terms of increasing conspicuousness of breeding males to females searching for mates.

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Insights about urinary hippuric and citric acid as biomarkers of fruit and vegetable intake in patients with kidney stones: The role of age and sex

Nutrition ◽

10.1016/j.nut.2018.07.112 ◽

2019 ◽

Vol 59 ◽

pp. 83-89 ◽

Cited By ~ 2

Author(s):

Angela Guerra ◽

Andrea Ticinesi ◽

Franca Allegri ◽

Antonio Nouvenne ◽

Beatrice Prati ◽

...

Keyword(s):

Citric Acid ◽

Kidney Stones ◽

Vegetable Intake ◽

Fruit And Vegetable Intake ◽

Fruit And Vegetable ◽

Age And Sex

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The epidemiology of Sarcocystis spp. in cattle of Western Australia

Epidemiology and Infection ◽

10.1017/s0950268800049554 ◽

1992 ◽

Vol 108 (1) ◽

pp. 107-113 ◽

Cited By ~ 23

Author(s):

G. Savini ◽

J. D. Dunsmore ◽

I. D. Robertson ◽

P. Seneviratna

Keyword(s):

Western Australia ◽

Host Age ◽

Semiarid Regions ◽

Sex Influence ◽

Sarcocystis Spp ◽

Artificial Digestion ◽

Management Factors ◽

Arid And Semiarid ◽

Age And Sex

SUMMARYOesophagus samples from 714 cattle from Western Australia were examined by artificial digestion to detect the presence of Sarcocystis spp. The overall prevalence of infection was 52%. The prevalence of infection increased with age and was highest in the entire males (92%). The prevalence was lower in cattle which originated from arid and semiarid regions (9 and 31% respectively) than those from tropical (87%) and temperate (60%) regions. possible reasons for these differences are discussed and it is concluded that environmental and management factors as well as host age and sex influence the prevalence of infection with Sarcocystis spp. in cattle.

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Helminth parasites of Jamaican anoles (Reptilia: Iguanidae): variation in prevalence and intensity with host age and sex in a population of Anolis lineatopus

Parasitology ◽

10.1017/s0031182000054044 ◽

1987 ◽

Vol 94 (2) ◽

pp. 399-404 ◽

Cited By ~ 18

Author(s):

P. Vogel ◽

D. A. P. Bundy

Keyword(s):

Direct Relationship ◽

Helminth Parasite ◽

Infection Prevalence ◽

Helminth Parasites ◽

Host Age ◽

Almost All ◽

Low Prevalence ◽

Age Range ◽

Age And Sex

SUMMARYThe Jamaican iguanid lizard Anolis lineatopus is the host of 4 species of helminth parasite: an acanthocephalan (Centrorhynchus spinosus), a digenean (Mesocoelium danforthi), and 2 nematodes (Cyrtosumum scelopori and Thelandros (?cubensis). Prevalance of C. spinosus was unrelated to host age but was considerably higher in males (43%) than in females (10%). The intensity increased with host age: (range: 1–23, median: 3). Prevalence of C. scelopori increased with host age in both sexes: juveniles (<3 months) were uninfected while infection occurred in almost all lizards older than 9 months. Intensity was higher in males (range: 1–403, median: 158) than in females (range: 1–297, median: 86). The infection patterns of C. spinosus and C. scelopori differed significantly from each other and were not consistent with a simplistic direct relationship between time of exposure and infection prevalence. Acanthocephalan and digenean infections occurred at low prevalence and intensity although prevalence in older, larger lizards tended to be higher than in younger, smaller ones.

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