Search results for "succe"
showing 10 items of 990 documents
Predictive Capacity of Boar Sperm Morphometry and Morphometric Sub-Populations on Reproductive Success after Artificial Insemination
2021
The aim of the study was to compare the morphometric features of sperm head sizeand shape from the Pietrain line and the Duroc×Pietrain boar crossbred terminal lines, and toevaluate their relationship with reproductive success after artificial insemination of sows producedfrom crossbreeding the York, Landrace and Pietrain breeds. Semen samples were collected from 11sexually mature boars. Only ejaculates with greater than 70% motility rate and <15% of abnormalsperm were used for artificial inseminations (AI) and included in the study. Samples were analyzedusing an ISAS®v1 computer-assisted sperm analysis system for eight morphometric parameters ofhead shape and size (CASA-Morph). Sub-populat…
Preguntòse si el substituto, que tacita, ò expressamente dà, y señala el Padre à su hijo, ò hijos pupilos, debe preferir à la Madre, de forma,…
1701
L'autor del dictamen al final: S.D.C Com a tít. el començament del text Caplletra grav. i banda a la p. 1 Sign.: A-E2 Reclams
"Ute i naturen lever jeg!" : pasienters opplevelser med natur i spesialisert nevrologisk rehabilitering
2013
Masteroppgave i helsefag ME 518 Universitetet i Agder 2013 Background: A holistic approach dominates when it comes to rehabilitation. The patient’s priorities and involvement are crucial to the quality of life, the ability for the patient to succeed and his or her feel of coherence. Research indicates that outdoor activities can have positive effects on physical, psychological sociable and spiritual levels. However, more research is needed regarding what specific designs of treatment are being carried out and how the different groups of patients respond to these. Purpose and thesis: This paper will try to establish an insight into how patients with neurological diseases perceive outdoor tre…
Imprints of latitude, host taxon, and decay stage on fungus-associated arthropod communities
2022
Interactions among fungi and insects involve hundreds of thousands of species. While insect communities on plants have formed some of the classic model systems in ecology, fungus-based communities and the forces structuring them remain poorly studied by comparison. We characterize the arthropod communities associated with fruiting bodies of eight mycorrhizal basidiomycete fungus species from three different orders along a 1200-km latitudinal gradient in northern Europe. We hypothesized that, matching the pattern seen for most insect taxa on plants, we would observe a general decrease in fungal-associated species with latitude. Against this backdrop, we expected local communities to be struc…
Scientific Reports
2020
.-- Halimubieke, Naerhulan et al.
No evidence for prezygotic postcopulatory avoidance of kin despite high inbreeding depression.
2018
11 pages; International audience; Offspring resulting from mating among close relatives can suffer from impaired fitness through the expression of recessive alleles with deleterious effects. Postcopulatory sperm selection (a prezygotic mechanism of cryptic female choice) has been suggested to be an effective way to avoid inbreeding. To investigate whether postcopulatory female choice allows the avoidance of fertilization by close kin, we performed artificial inseminations in a promiscuous bird, the houbara bustard (Chlamydotis undulata undulata). Females were inseminated with a mix of sperm from triads of males, each constituted of a male genetically unrelated to the female, a first cousin …
Stabilising selection on immune response in male black grouse Lyrurus tetrix
2017
Illnesses caused by a variety of micro- and macro- organisms can negatively affect individuals’ fitness, leading to the expectation that immunity is under positive selection. However, immune responses are costly and individuals must trade-off their immune response with other fitness components (e.g. survival or reproductive success) meaning that individuals with intermediate response may have the greatest overall fitness. Such a process might be particularly acute in species with strong sexual selection because the condition-dependence of male secondary sexual-traits might lead to striking phenotypic differences amongst males of different immune response levels. We tested whether there is s…
Sexual selection, phenotypic plasticity and female reproductive output
2019
In a rapidly changing environment, does sexual selection on males elevate a population's reproductive output? If so, does phenotypic plasticity enhance or diminish any such effect? We outline two routes by which sexual selection can influence the reproductive output of a population: a genetic correlation between male sexual competitiveness and female lifetime reproductive success; and direct effects of males on females' breeding success. We then discuss how phenotypic plasticity of sexually selected male traits and/or female responses (e.g. plasticity in mate choice), as the environment changes, might influence how sexual selection affects a population's reproductive output. Two key points…
SIGNAL RELIABILITY COMPROMISED BY GENOTYPE-BY-ENVIRONMENT INTERACTION AND POTENTIAL MECHANISMS FOR ITS PRESERVATION
2007
Sexual selection based on signaling requires that signals used by females in mate choice are reliable indicators of a male's heritable total fitness. A signal and the preference for it are expected to be heritable, resulting in the maintenance of genetic covariance between these two traits. However, a recent article has proposed that signals may quickly become unreliable in the presence of both environmental variation and genotype-by-environment interaction (G x E) with crossing reaction norms, potentially compromising the mechanisms of sexual selection. Here we examine the heritability and plasticity of a male dominance advertisement in the bank vole, Clethrionomys glareolus, in stable and…
FITNESS TRADE-OFFS MEDIATED BY IMMUNOSUPPRESSION COSTS IN A SMALL MAMMAL
2009
International audience; Trade-offs are widespread between life-history traits, such as reproduction and survival. However, their underlying physiological and behavioral mechanisms are less clear. One proposed physiological factor involves the trade-off between investment in male reproductive effort and immunity. Based on this hypothesis, we investigated differences in fitness between artificially selected immune response bank vole groups, Myodes glareolus. Significant heritability of immune response was found and a correlated response in testosterone levels to selection on immune function. Male reproductive effort, reproductive success, and survival of first generation offspring were assess…