Parasitism of damselflies (Enallagma boreale) by gregarines: sex biases and relations to adult survivorship

2002 ◽  
Vol 80 (1) ◽  
pp. 162-168 ◽  
Author(s):  
K R Hecker ◽  
M R Forbes ◽  
N J Léonard
Keyword(s):  
Confounding Factor ◽  
Host Age ◽  
Potential Confounding Factor ◽  
Adult Males ◽  
Intensity Of Infection ◽  
Male And Female ◽  
Adult Females ◽  
Males And Females ◽  
Enallagma Boreale ◽  
Sex Biases

We studied host damselflies Enallagma boreale (Odonata: Coenagrionidae) and their gregarine parasites (Apicomplexa: Eugregarinidae) to elucidate the causes and consequences of any sex biases in parasitism of adult hosts. Larvae of both sexes were highly infected, but there was no difference between male and female larvae in either prevalence or intensity of gregarine infections. Newly emerged adults had few or no parasites, thereby setting the stage for investigating accumulation of parasites by adults. Adult females had a higher prevalence and intensity of infection by gregarines than did males, but only on 1 (of 2) days when the potential confounding factor of host age was controlled for. Both adult males and females showed a positive correlation between longevity under conditions of food stress and the number of gregarines they initially carried. This finding may be explained if the food ingested with the infective cysts is more beneficial than the parasites are harmful, and it also has implications for investigating sex biases in numbers of trophically transmitted parasites of such insects.

scholarly journals Peak shift and epidemiology in a seasonal host–nematode system

2005 ◽  
Vol 272 (1568) ◽  
pp. 1163-1169 ◽  
Author(s):  
I.M Cattadori ◽  
B Boag ◽  
O.N Bjørnstad ◽  
S.J Cornell ◽  
P.J Hudson
Keyword(s):  
Negative Relationship ◽  
Peak Shift ◽  
Cumulative Exposure ◽  
Acquired Immunity ◽  
Host Age ◽  
Spatial Effects ◽  
Adult Males ◽  
Intensity Of Infection ◽  
Adult Females ◽  
Peak Intensity

Insight into the dynamics of parasite–host relationships of higher vertebrates requires an understanding of two important features: the nature of transmission and the development of acquired immunity in the host. A dominant hypothesis proposes that acquired immunity develops with the cumulative exposure to infection, and consequently predicts a negative relationship between peak intensity of infection and host age at this peak. Although previous studies have found evidence to support this hypothesis through between-population comparisons, these results are confounded by spatial effects. In this study, we examined the dynamics of infection of the nematode Trichostrongylus retortaeformis within a natural population of rabbits sampled monthly for 26 years. The rabbit age structure was reconstructed using body mass as a proxy for age, and the host age–parasite intensity relationship was examined for each rabbit cohort born from February to August. The age–intensity curves exhibited a typical concave shape, and a significant negative relationship was found between peak intensity of infection and host age at this peak. Adult females showed a distinct periparturient rise in T. retortaeformis infection, with higher intensities in breeding adult females than adult males and non-breeding females. These findings are consistent with the hypothesis of an acquired immune response of the host to a parasite infection, supporting the principle that acquired immunity can be modelled using the cumulative exposure to infection. These findings also show that seasonality can be an important driver of host–parasite interactions.

scholarly journals Comparison of Aerodynamic Characteristics During Reading Paragraph Tasks in Normal Male and Female Adults

2020 ◽  
Vol 16 (4) ◽  
pp. 356-362
Author(s):  
Hwa-Young Pyo
Keyword(s):  
Total Duration ◽  
Aerodynamic Characteristics ◽  
Normal Adult ◽  
Voice Disorder ◽  
Normal Male ◽  
Adult Males ◽  
Male And Female ◽  
Adult Females ◽  
Males And Females ◽  
The Difference

Purpose: The present study was performed to compare the aerodynamic characteristics of males and females during reading paragraph task.Methods: Thirty-seven normal adult males (18-30 yrs) and thirty-nine normal adult females (18-34 yrs) were participated in this experiment. They read a part of ‘Gaeul’ paragraph with comfortable phonation, and the reading samples were recorded and analyzed by ‘Running Speech’ program of Phonatory Aerodynamic System (PAS).Results: Phonation time (with voicing) and expiratory airflow duration were significantly longer in females, but measures of inspiratory airflow duration, peak expiratory airflow, expiratory and inspiratory volumes were significantly higher in males. The difference in total duration and peak inspiratory airflow did not show statistical significance.Conclusion: Results revealed that there was a significant gender difference in aerodynamic measures of duration and airflow during the reading paragraph task. In evaluating and intervening aerodynamics of voice and voice disorder patients, we should also consider the gender-different aerodynamic characteristics in continuous speech.

DEVELOPMENT AND BIONOMICS OF CHRYSOMELOBIA LABIDOMERAE (ACARI: TARSONEMINA; PODAPOLIPIDAE), A PARASITE OF THE MILKWEED LEAF BEETLE (COLEOPTERA: CHRYSOMELIDAE)

1975 ◽  
Vol 107 (6) ◽  
pp. 627-638 ◽  
Author(s):  
Thomas C. Baker ◽  
George C. Eickwort
Keyword(s):  
Leaf Beetle ◽  
High Population ◽  
Immature Stages ◽  
Adult Males ◽  
Nymphal Instar ◽  
Male And Female ◽  
Adult Females ◽  
Original Length ◽  
Chrysomelobia Labidomerae ◽  
Pharate Adult

AbstractAdult females of Chrysomelobia labidomerae Eickwort lay eggs on the upper surfaces of the hind wings of Labidomera clivicollis (Kirby). The eggs hatch in approximately 7 days and male and female larvae feed at the base of the wings and in the meso–metathoracic crevice and swell to about twice their original length. For about the second half of the approximately 7-day larval stadium, the larvae are inactive (pharate adults) and are usually cemented to the undersurfaces of the elytra. Inactive female larvae are accompanied by adult males that apparently copulate with the newly emerged adult females. The pharate adult is enclosed in a cuticular sac that may represent a calyptostatic nymphal instar. Adult females feed on the beetle’s abdominal terga and sometimes also occur on its venter where they do not feed. Females disperse from host to host when the beetles copulate. The species is arrhenotokous. Mites overwinter on the diapausing adult beetles and do not infest the immature stages of their host. Even at high population levels, the mites do not noticeably affect the longevity or fecundity of their hosts.

scholarly journals The Diet and Sexual Differences of the Caspian Bent-Toed Gecko,Tenuidactylus caspius(Squamata: Gekkonidae), in Northern Iran

2014 ◽  
Vol 2014 ◽  
pp. 1-4 ◽  
Author(s):  
Vida Hojati ◽  
Reza Babaei Savasari
Keyword(s):  
Sexual Dimorphism ◽  
Culex Pipiens ◽  
Tail Length ◽  
Adult Males ◽  
Northern Iran ◽  
Widespread Distribution ◽  
Adult Females ◽  
Significant Difference ◽  
Males And Females ◽  
Prey Items

The Caspian bent-toed gecko,Tenuidactylus caspius, is one of the most common nocturnal lizards of Iran with widespread distribution especially in the northern provinces. This research was done in order to study the diet and sexual dimorphism of this species in Sari County from 5 May to 20 October. During this research, 40 specimens of them including 20 males and 20 females were studied for diet and 140 specimens including 70 adult males and 70 adult females were studied for sexual dimorphism. Prey items identified were insects that belong to 15 species of 8 families and 6 orders. The most common prey items wereCulex pipiensandMusca domestica. There is no significant difference between diets of males and females. Results show that the adult males in addition of having the apparent femoral and preanal pores are heavier than females and have larger body, head, and tail length.

GONADOTROPHIN PATTERNS IN MALE AND FEMALE RATS: PLASMA LH AND FSH AT VARIOUS AGES EVALUATED BY THE METHOD OF PARABIOSIS

1967 ◽  
Vol 56 (1) ◽  
pp. 165-176 ◽  
Author(s):  
Donald C. Johnson
Keyword(s):  
Follicle Stimulating Hormone ◽  
Chorionic Gonadotrophin ◽  
Female Rats ◽  
Adult Males ◽  
Male And Female ◽  
Ovarian Weight ◽  
Average Value ◽  
Male And Female Rats ◽  
Tonic Level ◽  
Males And Females

ABSTRACT Ventral prostates in hypophysectomized male parabiotic partners of intact animals were used to compare the amount of plasma luteinizing hormone (LH) in males and females of various ages. Ovarian weight, histology, and augmentation with chorionic gonadotrophin, in hypophysectomized androgenized females were used to estimate plasma follicle stimulating hormone (FSH) activity in intact adult males and females. In young animals, up to 50 days of age, males apparently have the same amount of plasma LH as females, but older cyclic females produced significantly heavier prostates in their hypophysectomized male partners than did males. The results are consistent with the interpretation that cyclic surges of LH added to a tonic level produced an average value higher for females than males. In contrast, males of all ages and particularly adults, have a significantly greater amount of circulating FSH than females.

The effect of non-immune stresses on the development of Strongyloides ratti

Parasitology ◽  
2005 ◽  
Vol 131 (3) ◽  
pp. 383-392 ◽  
Author(s):  
M. CROOK ◽  
M. E. VINEY
Keyword(s):  
Immune Response ◽  
Parasitic Nematode ◽  
Host Immune Response ◽  
Natural Host ◽  
Adult Males ◽  
Free Living ◽  
Developmental Effects ◽  
Adult Females ◽  
Males And Females ◽  
Living Adult

Strongyloides ratti is a parasitic nematode of rats. The host immune response against S. ratti affects the development of its free-living generation, favouring the development of free-living adult males and females at the expense of directly developing, infective 3rd-stage larvae. However, how the host immune response brings about these developmental effects is not clear. To begin to investigate this, we have determined the effect of non-immune stresses on the development of S. ratti. These non-immune stresses were subcurative doses of the anthelmintic drugs Ivermectin, Dithiazanine iodide and Thiabendazole, and infection of a non-natural host, the mouse. These treatments produced the opposite developmental outcome to that of the host immune response. Thus, in infections treated with subcurative doses of Ivermectin, Dithiazanine iodide and in infections of a non-natural host, the sex ratio of developing larvae became more female-biased and the proportion of female larvae that developed into free-living adult females decreased. This suggests that the mechanism by which the host immune response and these non-immune stresses affect S. ratti development differs.

Cuticular and internal n-alkane composition of Lucilia sericata larvae, pupae, male and female imagines: application of HPLC-LLSD and GC/MS-SIM

2012 ◽  
Vol 102 (4) ◽  
pp. 453-460 ◽  
Author(s):  
M. Gołębiowski ◽  
M. Paszkiewicz ◽  
A. Grubba ◽  
D. Gąsiewska ◽  
M.I. Boguś ◽  
...  
Keyword(s):  
Lucilia Sericata ◽  
Cuticular Lipids ◽  
Ion Current ◽  
Hydrocarbon Fraction ◽  
Adult Males ◽  
Selected Ion Monitoring ◽  
Male And Female ◽  
Carbon Chains ◽  
Males And Females

AbstractThe composition of cuticular and internal n-alkanes in Lucilia sericata larvae, pupae, and male and female imagines were studied. The cuticular and internal lipid extracts were separated by HPLC-LLSD, after which the hydrocarbon fraction was identified by GC/MS in selected ion monitoring (SIM) and total ion current (TIC) modes.The cuticular lipids of the larvae contained seven n-alkanes from C23 to C31. The major n-alkane in L. sericata larvae was C29 (42.1%). The total cuticular n-alkane content in the cuticular lipids was 31.46 μg g−1 of the insect body. The internal lipids of L. sericata larvae contained five n-alkanes ranged from C25 to C31. The most abundant compound was C27 (61.71 μg g−1 of the insect body). Eighteen n-alkanes from C14 to C31 were identified in the cuticular lipids of the pupae. The most abundant n-alkanes ranged from C25 to C31; those with odd-numbered carbon chains were particularly abundant, the major one being C29:0 (59.5%). Traces of eight cuticular n-alkanes were present. The internal lipids of L. sericata pupae contained five n-alkanes, ranging from C25 to C31. The cuticular lipids of female imagines contained 17 n-alkanes from C12 to C30. Among the cuticular n-alkanes of females, C27 (47.5%) was the most abundant compound. Four n-alkanes, with only odd-numbered carbon chains, were identified in the internal lipids of females. The lipids from both sexes of L. sericata had similar n-alkane profiles. The cuticular lipids of adult males contained 16 n-alkanes ranging from C13 to C31. C27 (47.9%) was the most abundant cuticular n-alkanes in males. The same n-alkanes only with odd-numbered carbon chains and in smaller quantities of C27 (0.1%) were also identified in the internal lipids of males.The highest amounts of total cuticular n-alkanes were detected in males and females of L. sericata (330.4 and 158.93 μg g−1 of the insect body, respectively). The quantities of total cuticular alcohols in larvae and pupae were smaller (31.46 μg g−1 and 42.08 μg g−1, respectively). The internal n-alkane contents of larvae, pupae, and male and female imagines were significantly higher than the cuticular n-alkane contents (153.53, 99.60, 360.06 and 838.76 μg g−1 of the insect body, respectively).

scholarly journals Multiple Toll-Spätzle Pathways in Drosophila melanogaster Immunity

2018 ◽  
Author(s):  
Munmun Chowdhury ◽  
Chun-Feng Li ◽  
Zhen He ◽  
Yuzhen Lu ◽  
Xusheng Liu ◽  
...  
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Drosophila Melanogaster ◽  
Candida Albicans ◽  
Systemic Infection ◽  
Defense Responses ◽  
Immune Defense ◽  
Adult Males ◽  
Male And Female ◽  
Vesicular Stomatitis ◽  
Males And Females

AbstractThe Drosophila melanogaster Toll-Spätzle pathway plays an important role in development and immunity. Drosophila genome encodes nine Toll receptors and six Spätzle (Spz) proteins, and only the canonical Toll-Spz (Toll-1-Spz-1) pathway has been well investigated. In this study, we compared the nine Drosophila Tolls and showed that similarly to Toll, Toll-7 also strongly activated drosomycin promoter. Importantly, we showed that both Toll and Toll-7 interacted with Spz, Spz-2 and Spz-5, and co-expression of Toll or Toll-7 with Spz, Spz-2 and Spz-5 activated the drosomycin promoter. Furthermore, Toll and Toll-7 both recognized vesicular stomatitis virus (VSV) by binding to the VSV glycoprotein. Septic infection in Toll and Toll-7 mutant flies suggested that Toll and Toll-7 differentially affected defense responses in adult males and females after systemic infection by Enterococcus faecalis, Pseudomonas aeruginosa, Candida albicans or VSV. Our results suggest multiple Toll family members activate the expression of antimicrobial peptides. Our results also provide evidence that Toll and Toll-7 bind multiple Spätzle proteins and differentially affect immune defense against different pathogens in adult male and female flies.

Home-Range Size and Fidelity of Western Grey Kangaroos (Macropus Fuliginosus) Living in Remnants of Wandoo Woodland and Adjacent Farmland.

1992 ◽  
Vol 19 (2) ◽  
pp. 137 ◽  
Author(s):  
GW Arnold ◽  
DE Steven ◽  
A Grassia ◽  
J Weeldenburg
Keyword(s):  
Home Range Size ◽  
Home Ranges ◽  
Adult Males ◽  
The Core ◽  
Adult Females ◽  
Radio Transmitters ◽  
Core Areas ◽  
Males And Females ◽  
Eucalyptus Wandoo ◽  
Older Males

The home ranges were studied from 1977 to 1981 of western grey kangaroos (Macropus fuliginosus) living in a 300-ha remnant of wandoo [Eucalyptus wandoo] surrounded by farmland at Baker's Hill, Western Australia. The M. fuliginosus population varied from 140 to 200 animals during the study. In 1979, four females (>30 kg) and 2 adult males (31 kg and 47 kg) were fitted with radio-transmitters and their movements recorded. The home ranges of these animals varied from 39 to 70 ha; the average overlap in the area used during the day and that used at night was 16.4%. Many of the kangaroos fed on farmland at night. The night ranges of 51 marked kangaroos were recorded using a spotlight. The animals showed a strong fidelity to their home ranges. Only 3 males (about 5-yr-old) shifted their night ranges; the centres of the ranges moved only 600-800 m. Older males had significantly larger night ranges than younger males and females. Individual females and the younger males showed preferences for using particular access points to get onto farmland; the older males showed no preferences. The core areas of the night ranges of many adult females overlapped closely in 'groups', but there was no evidence of 'mob' home ranges that were socially separated.

Roads, routes and rams: does sexual segregation contribute to anthropogenic risk in a desert-dwelling ungulate?

2016 ◽  
Vol 43 (5) ◽  
pp. 380 ◽  
Author(s):  
Vernon C. Bleich ◽  
Jericho C. Whiting ◽  
John G. Kie ◽  
R. Terry Bowyer
Keyword(s):  
Bighorn Sheep ◽  
Ovis Canadensis ◽  
Sexual Segregation ◽  
Adult Males ◽  
Large Mammals ◽  
Male And Female ◽  
Use Of Resources ◽  
Core Areas ◽  
Males And Females ◽  
Time Of Year

Context Little is known about the consequences of sexual segregation (differential use of resources by the sexes outside of the mating season) for the conservation of large mammals. Roadways (i.e. the strip of land over which a road or route passes) are ubiquitous around the world, and are a major cause of wildlife mortality, as well as habitat loss and fragmentation. Many populations of bighorn sheep (Ovis canadensis) occur at low densities and in a metapopulation structure. Roadways could affect movements of males and females differentially, an outcome that has not been considered previously. Aims We investigated the propensity of the sexes to cross a paved two-lane road and a single-lane, maintained dirt route and predicted that adult males, because of their life-history characteristics, would cross those roadways more often than females. Methods We investigated movements of male and female bighorn sheep from 1986 to 1990. We used a fixed-wing aircraft with an H-antenna on each wing strut to locate individuals each week from October 1986 to December 1990. We estimated the degree of overlap among 50% core areas of use by males and females with the utilisation distribution overlap index (UDOI). Key results We relocated male and female bighorn sheep on 948 occasions during sexual aggregation and on 1951 occasions during sexual segregation. More males than females were likely to cross both types of roadways during segregation, and the dirt route during aggregation. Propensity of males and females to cross roadways was strongly influenced by time of year (i.e. whether the period of sexual aggregation or sexual segregation). The lowest overlap in 50% core areas was between females and males during periods of segregation (UDOI = 0.1447). Conclusions More males than females crossed Kelbaker Road and the unnamed dirt route during segregation, as well as the unnamed route during aggregation. Both of those features could affect males more than females, and could result in reductions in the use of habitat or increased mortality of bighorn sheep from vehicle collisions as a result of spatial segregation of the sexes. Implications During environmental review, biologists should consider sexual segregation when assessing potential anthropogenic effects on movements of bighorn sheep. Biologists also should consider sexual segregation and how roadways, even lightly traveled routes, affect movements of male and female ungulates differently before manipulating habitat, translocating animals, or constructing or modifying roadways.

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