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1.

001-es BibID:BIBFORM107672
035-os BibID:(WoS)000368560000005 (Scopus)84957921974
Első szerző:Krause, Jesse S.
Cím:Annual Hematocrit Profiles in Two Subspecies of White-Crowned Sparrow : A Migrant and a Resident Comparison / Jesse S. Krause, Zoltán Németh, Jonathan H. Pérez, Helen E. Chmura, Marilyn Ramenofsky, John C. Wingfield
Dátum:2016
ISSN:1522-2152
Megjegyzések:Hematocrit is an easily measured parameter that can be used to assess changes in oxygen carrying capacity necessitated by fluctuations in metabolic demands. Most hematocrit studies draw conclusions from changes in hematocrit that occur over a small sampling interval without an understanding of the variation that exists across the annual cycle. White-crowned sparrows provide an excellent model system due to the existence of a resident subspecies (Zonotrichia leucophrys nuttalli) that serves as a natural control for a migrant subspecies (Zonotrichia leucophrys gambelii). Comparing these two subspecies allows for the investigation of adaptive physiological changes at each life-history stage (i.e., migration, breeding, molt, etc.) in response to changing metabolic demands. Of particular interest, this subspecies comparison, by both calendar month and lifehistory stage, allows for the separation of adaptive increases in hematocrit due to migration fromthe natural seasonal variation in hematocrit. Hematocrit levels for males and females ranged throughout the year between 42%?47% and 40%?47% in the resident and between 45%?58% and 45%?56% in the migrant. In both subspecies, hematocrit levels were elevated during the breeding season compared to the nonbreeding season, and levels were reduced in females during egg laying. When grouped by life-history stage, hematocrit levels were always higher in the migrant compared to the resident. During the months in which migration occurred, hematocrit levels were 10%?12% higher in the migrant compared to the resident subspecies. These data suggest differential regulation of hematocrit between the two subspecies that may be attributed to phenotypic plasticity or genetic differences.
Tárgyszavak:Természettudományok Biológiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban
folyóiratcikk
life-history stage
migration, molt
breeding biology
red blood cells
annual cycle
Megjelenés:Physiological And Biochemical Zoology. - 89 : 1 (2016), p. 51-60. -
További szerzők:Németh Zoltán (1976-) (biológus) Pérez, Jonathan H. Chmura, Helen E. Ramenofsky, Marilyn Wingfield, John C.
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2.

001-es BibID:BIBFORM062824
Első szerző:Moskát Csaba
Cím:Naïve hosts of avian brood parasites accept foreign eggs, whereas older hosts fine-tune foreign egg discrimination during laying / Csaba Moskát, Miklós Bán, Márk E Hauber
Dátum:2014
ISSN:1742-9994
Megjegyzések:Background: Many potential hosts of social parasites recognize and reject foreign intruders, and reduce or altogether escape the negative impacts of parasitism. The ontogenetic basis of whether and how avian hosts recognize their own and the brood parasitic eggs remains unclear. By repeatedly parasitizing the same hosts with a consistent parasitic egg type, and contrasting the responses of naïve and older breeders, we studied ontogenetic plasticity in the rejection of foreign eggs by the great reed warbler (Acrocephalus arundinaceus), a host species of the common cuckoo (Cuculus canorus).Results: In response to experimental parasitism before the onset of laying, first time breeding hosts showed almost no egg ejection, compared to higher rates of ejection in older breeders. Young birds continued to accept foreign eggs when they were subjected to repeated parasitism, whereas older birds showed even higher ejection rates later in the same laying cycle.Conclusions: Our results are consistent with the hypotheses that (i) naïve hosts need to see and learn the appearance of their own eggs to discriminate and reject foreign eggs, whereas (ii) experienced breeders possess a recognition template of their own eggs and reject parasitic eggs even without having to see their own eggs. However, we cannot exclude the possibility that other external cues and internal processes, accumulated simply with increasing age, may also modify age-specific patterns in egg rejection (e.g. more sightings of the cuckoo by older breeders). Future research should specifically track the potential role of learning in responses of individual hosts between first and subsequent breeding attempts by testing whether imprinting on a parasitized clutch reduces the rates of rejecting foreign eggs in subsequent parasitized clutches.
Tárgyszavak:Természettudományok Biológiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban
Adaptation
Brood parasitism
Clutch learning
Egg discrimination
Élettudományok - Biológiai tudományok
Megjelenés:Frontiers in Zoology. - 11 : 1 (2014), p. [8]. -
További szerzők:Bán Miklós (1975-) (biológus) Hauber, Márk E.
Pályázati támogatás:OTKA-83217
OTKA
MTA-DE Lendület
MTA
Viselkedésökológiai Kutatócsoport
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3.

001-es BibID:BIBFORM084930
Első szerző:Pap Péter László (ökológus)
Cím:No Evidence for Parasitism-Linked Changes in Immune Function or Oxidative Physiology over the Annual Cycle of an Avian Species / Pap Péter László, Alina Sesarman, Vágási István Csongor, Deborah M. Buehler, Laura Patras, Maaike A. Versteegh, Manuela Banciu
Dátum:2014
Megjegyzések:Temporally changing environmental conditions occur in most parts of the world and can exert strong pressure on the immune defense of organisms. Seasonality may result in changes in physiological traits over the year, and such changes may be essential for the optimization of defense against infections. Evidence from field and laboratory studies suggest the existence of links between environmental conditions, such as infection risk, and the ability of animals to mount an immune response or to overcome infections; however, the importance of parasites in mediating seasonal change in immune defense is still debated. In this study, we test the hypothesis that seasonal change in immune function and connected physiological traits is related to parasite infection. We sampled captive house sparrows (Passer domesticus) once every 2 mo over 14 mo and compared the annual variation in 12 measures of condition, immune function, antioxidant status, and oxidative damage among birds naturally infested with coccidians or medicated against these parasites. We found significant variation in 10 of 12 traits over the year. However, we found little support for parasite-mediated change in immune function and oxidative status in captive house sparrows. Of the 12 measures, only one was slightly affected by parasite treatment. In support of the absence of any effect of coccidians on the annual profile of the condition and physiological traits, we found no consistent relationships between the intensity of infestation and these response variables over the year. Our results show that chronic coccidian infections have limited effect on the seasonal changing of physiological traits and that the patterns of these measures are probably more affected by acute infection and/or virulent parasite strains.
Tárgyszavak:Természettudományok Biológiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban
folyóiratcikk
Megjelenés:Physiological and Biochemical Zoology. - 87 : 5 (2014), p. 729-739. -
További szerzők:Sesarman, Alina Vágási Csongor István Buehler, Deborah M. Pătraş, Laura Versteegh, Maaike A. Banciu, Manuela
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4.

001-es BibID:BIBFORM083229
Első szerző:Pap Péter László (ökológus)
Cím:Seasonal Patterns and Relationships among Coccidian Infestations, Measures of Oxidative Physiology, and Immune Function in Free-Living House Sparrows over an Annual Cycle / Péter L. Pap, Laura Pătraş, Gergely Osváth, Deborah M. Buehler, Maaike A. Versteegh, Alina Sesarman, Manuela Banciu, Csongor I. Vágási
Dátum:2015
ISSN:1522-2152
Megjegyzések:Temporal variation in oxidative physiology and its associated immune function may occur as a result of changes in parasite infection over the year. Evidence from field and laboratory studies suggests links between infection risk, oxidative stress, and the ability of animals to mount an immune response; however the importance of parasites in mediating seasonal change in physiological make-up is still debated. Also, we know almost nothing about the temporal consistency of relationships among parasite infestation, markers of oxidative status and immune function in wild animals, and whether variation in oxidative measures can be viewed as a single integrated system. To address these questions, we sampled free-living house sparrows (Passer domesticus) every two months over a complete year and measured infestation with coccidian parasites, as well as 9 traits that reflect condition, oxidative physiology and immune function. We found significant seasonal variation in coccidian infestation and in 7 out of 9 condition and physiological variables over the year. However, we found little support for parasite-mediated change in condition, oxidative physiology and immune functions in house sparrows. In accordance with this, we found no temporal consistency in relationships between the intensity of infestation and physiology. Among measures of oxidative physiology, antioxidants (measured as the total antioxidant capacity and the concentration of uric acids in the plasma) and oxidative damage (measured through the level of malondialdehyde in plasma) positively and consistently covaried over the year, while no such associations were found for the rest of traits (body mass, total glutathione and leukocyte numbers). Our results show that natural levels of chronic coccidian infection have limited effect on the seasonal change of physiological traits, suggesting that the variation of the latter are probably more affected by short term disturbances, such as acute infection and/or season-specific stress stimuli.
Tárgyszavak:Természettudományok Biológiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban
folyóiratcikk
birds
heterophil to lymphocyte ratio
leukocyte count
oxidative status
parasites
seasonality
Megjelenés:Physiological and Biochemical Zoology. - 88 : 4 (2015), p. 395-405. -
További szerzők:Pătraş, Laura Osváth Gergely (1985-) (biológus) Buehler, Deborah M. Versteegh, Maaike A. Sesarman, Alina Banciu, Manuela Vágási Csongor István
Pályázati támogatás:TÁMOP-4.2.4.A/2-11/1-2012-0001
TÁMOP
GTC 34062/2013
Egyéb
PN II. RU TE 291/2010
Egyéb
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5.

001-es BibID:BIBFORM087510
Első szerző:Rosa Márta Erzsébet
Cím:Size-dependent investment in tusk length, testis size and sperm length in a biparental geotrupid beetle / M. E. Rosa, J. Kiss, Z. Barta, A. Kosztolányi
Dátum:2019
ISSN:0952-8369
Megjegyzések:Males of extreme small or large sizes often experience different levels of pre- and postcopulatory sexual selection that result in alternative ways to gain fertilization success. Here, we investigated such alternative mating tactics in Lethrus apterus, a biparental geotrupid beetle species with noticeable intermale size variation by comparing tusk (mandibular process) length, testis size and sperm length between large and small males. Firstly, we demonstrated evidence for male polymorphism as extremely large males had longer tusks relative to their body size than extremely small individuals. Secondly, large males had bigger testes than small males throughout the breeding season, however, a significant decrease was observed overtime in large but not in small individuals. Thirdly, sperm length did not differ between the two size categories. Although these results do not explain how the observed large body size variation can be maintained in L. apterus, the non allo-metric relationship found between tusk length and body size and the lower decrease in testis size over the breeding season in case of small individuals might refer to the presence of alternative mating tactics in this species.
Tárgyszavak:Természettudományok Biológiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban
folyóiratcikk
body size
sperm competition
reproductive strategies
insects
Geotrupidae
polymorphism
testis size
Lethrus apterus
Megjelenés:Journal of Zoology. - 309 : 2 (2019), p. 106-113. -
További szerzők:Kiss Johanna (1989-) (zoológus) Barta Zoltán (1967-) (biológus, zoológus) Kosztolányi András (1971-) (biológus)
Pályázati támogatás:EFOP-3.6.1-16-2016-00022
EFOP
NKFIH K112670
egyéb
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6.

001-es BibID:BIBFORM096003
035-os BibID:(Scopus)84999027902 (WOS)000396964700012
Első szerző:Tökölyi Jácint (biológus)
Cím:Resource allocation and post-reproductive degeneration in the freshwater cnidarian Hydra oligactis (Pallas, 1766) / Tökölyi Jácint, Ősz Zsófia, Sebestyén Flóra, Barta Zoltán
Dátum:2017
ISSN:0944-2006
Megjegyzések:Freshwater hydra are among the few animal groups that show negligible senescence and can maintain high survival and reproduction rates when kept under stable conditions in the laboratory. Yet, one species of Hydra (H. oligactis) undergoes a senescence-like process in which polyps degenerate and die after sexual reproduction. The ultimate factors responsible for this phenomenon are unclear. High mortality in reproducing animals could be the consequence of increased allocation of resources to reproduction at the expense of somatic maintenance. This hypothesis predicts that patterns of reproduction and survival are influenced by resource availability. To test this prediction we investigated survival and reproduction at different levels of food availability in 10 lineages of H. oligactis derived from a single Hungarian population. Sexual reproduction was accompanied by reduced survival, but a substantial proportion of animals regenerated after sexual reproduction and continued reproducing asexually. Polyps belonging to different lineages showed differences in their propensity to initiate sexual reproduction, gonad number and survival rate. Food availability significantly affected fecundity (number of eggs or testes produced), with the largest number of gonads being produced by animals kept on a high food regime. On the other hand, survival rate was not affected by the amount of food. These results show that survival is conserved at the expense of reproduction in this population when food is low. It remains a question still to be answered why survival is prioritized over reproduction in this population.
Tárgyszavak:Természettudományok Biológiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban
folyóiratcikk
Cnidaria
Food availability
Life history
Senescence
Survival/reproduction trade-offs
Megjelenés:Zoology. - 120 (2017), p. 110-116. -
További szerzők:Ősz Zsófia Sebestyén Flóra (1993-) (biológus) Barta Zoltán (1967-) (biológus, zoológus)
Pályázati támogatás:NTP-EFÖ-P-15
Egyéb
János Bolyai Research Scholarship of the Hungarian Academy of Sciences
Egyéb
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