Density-dependent effects on reproductive performance in a recovering population of White-tailed Eagles Haliaeetus albicilla

AbstractAcross group-living animals, linear dominance hierarchies lead to disparities in access to resources, health outcomes, and reproductive performance. Studies of how dominance rank affects these outcomes typically employ one of several dominance rank metrics without examining the assumptions each metric makes about its underlying competitive processes. Here we compare the ability of two dominance rank metrics—ordinal rank and proportional or ‘standardized’ rank—to predict 20 distinct traits in a well-studied wild baboon population in Amboseli, Kenya. We propose that ordinal rank best predicts outcomes when competition is density-dependent, while proportional rank best predicts outcomes when competition is density-independent. We found that for 75% (15/20) of the traits, one of the two rank metrics performed better than the other. Strikingly, all male traits were better predicted by ordinal than by proportional rank, while female traits were evenly split between being better predicted by proportional or ordinal rank. Hence, male and female traits are shaped by different competitive regimes: males’ competitive environments are largely driven by density-dependent resource access (e.g., access to estrus females), while females’ competitive environments are shaped by both density-independent resource access (e.g. distributed food resources) and density-dependent resource access. However, traits related to competition for social and mating partners are an exception to this sex-biased pattern: these traits were better predicted by ordinal rank than by proportional rank for both sexes. We argue that this method of comparing how different rank metrics predict traits of interest can be used as a way to distinguish between different competitive processes operating in animal societies.

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A comparison of dominance rank metrics reveals multiple competitive landscapes in an animal society

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2020.1013 ◽

2020 ◽

Vol 287 (1934) ◽

pp. 20201013 ◽

Cited By ~ 1

Author(s):

Emily J. Levy ◽

Matthew N. Zipple ◽

Emily McLean ◽

Fernando A. Campos ◽

Mauna Dasari ◽

...

Keyword(s):

Performance Studies ◽

Reproductive Performance ◽

Dominance Rank ◽

Group Living ◽

Dominance Hierarchies ◽

Resource Access ◽

Density Dependent ◽

Rank Metric ◽

Animal Societies ◽

Better Than

Across group-living animals, linear dominance hierarchies lead to disparities in access to resources, health outcomes and reproductive performance. Studies of how dominance rank predicts these traits typically employ one of several dominance rank metrics without examining the assumptions each metric makes about its underlying competitive processes. Here, we compare the ability of two dominance rank metrics—simple ordinal rank and proportional or ‘standardized’ rank—to predict 20 traits in a wild baboon population in Amboseli, Kenya. We propose that simple ordinal rank best predicts traits when competition is density-dependent, whereas proportional rank best predicts traits when competition is density-independent. We found that for 75% of traits (15/20), one rank metric performed better than the other. Strikingly, all male traits were best predicted by simple ordinal rank, whereas female traits were evenly split between proportional and simple ordinal rank. Hence, male and female traits are shaped by different competitive processes: males are largely driven by density-dependent resource access (e.g. access to oestrous females), whereas females are shaped by both density-independent (e.g. distributed food resources) and density-dependent resource access. This method of comparing how different rank metrics predict traits can be used to distinguish between different competitive processes operating in animal societies.

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Density-dependent reproduction in the European rabbit: a consequence of individual response and age-dependent reproductive performance

Oikos ◽

10.1111/j.0030-1299.2004.12691.x ◽

2004 ◽

Vol 104 (3) ◽

pp. 529-539 ◽

Cited By ~ 51

Author(s):

Heiko G. Rödel ◽

Agnes Bora ◽

Jürgen Kaiser ◽

Paul Kaetzke ◽

Martin Khaschei ◽

...

Keyword(s):

Reproductive Performance ◽

European Rabbit ◽

Individual Response ◽

Density Dependent ◽

Age Dependent

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Estimation of heterotic components for lactation traits and reproductive performance in three crossbreeding trials of Holstein cattle with German Friesian raised under hot climatic conditions

Journal of Animal Breeding and Genetics ◽

10.1046/j.1439-0388.2000.00230.x ◽

2000 ◽

Vol 117 (3) ◽

pp. 129-142 ◽

Cited By ~ 2

Author(s):

M. H. Khalil ◽

E. A. Afifi ◽

M. A. Salem ◽

S. M. Zahed

Keyword(s):

Reproductive Performance ◽

Climatic Conditions ◽

Holstein Cattle

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Urbanization impacts on production and recruitment of Fundulus heteroclitus in salt marsh creeks

Marine Ecology Progress Series ◽

10.3354/meps13378 ◽

2020 ◽

Vol 645 ◽

pp. 187-204

Author(s):

PJ Rudershausen ◽

JA Buckel

Keyword(s):

Salt Marsh ◽

Salt Marshes ◽

Fundulus Heteroclitus ◽

Multiple Factor Analysis ◽

Southeastern Usa ◽

Density Dependent ◽

Dependent Relationship ◽

Juvenile Abundance ◽

The Relationship ◽

Throw Trap

It is unclear how urbanization affects secondary biological production in estuaries in the southeastern USA. We estimated production of larval/juvenile Fundulus heteroclitus in salt marsh areas of North Carolina tidal creeks and tested for factors influencing production. F. heteroclitus were collected with a throw trap in salt marshes of 5 creeks subjected to a range of urbanization intensities. Multiple factor analysis (MFA) was used to reduce dimensionality of habitat and urbanization effects in the creeks and their watersheds. Production was then related to the first 2 dimensions of the MFA, month, and year. Lastly, we determined the relationship between creek-wide larval/juvenile production and abundance from spring and abundance of adults from autumn of the same year. Production in marsh (g m-2 d-1) varied between years and was negatively related to the MFA dimension that indexed salt marsh; higher rates of production were related to creeks with higher percentages of marsh. An asymptotic relationship was found between abundance of adults and creek-wide production of larvae/juveniles and an even stronger density-dependent relationship was found between abundance of adults and creek-wide larval/juvenile abundance. Results demonstrate (1) the ability of F. heteroclitus to maintain production within salt marsh in creeks with a lesser percentage of marsh as long as this habitat is not removed altogether and (2) a density-dependent link between age-0 production/abundance and subsequent adult recruitment. Given the relationship between production and marsh area, natural resource agencies should consider impacts of development on production when permitting construction in the southeastern USA.

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РОДСТВЕННЫЕ ГРУППЫ РЕДКИХ ПОРОД ГУСЕЙ

10.33845/0033-3239-2019-68-4-20-25 ◽

2019 ◽

Keyword(s):

Reproductive Performance ◽

Gene Pool

ЖАРКОВА И.П., ГРИШИНА Д. С. Федеральный научный центр «Всероссийский научно-исследовательский и технологический институт птицеводства» Российской академии наук Аннотация: Авторами изучены генетические параметры хозяйственно-полезных признаков гусей (сохранность, яйценоскость, масса яиц, оплодотворенность и выводимость яиц, вывод гусят) в зависимости от их происхождения. Новизна работы заключается в том, что впервые проведен анализ закономерностей проявления репродуктивных качеств у родственных групп гусей. При сравнительном изучении 21 породы гусей установлено, что группа пород гусей, родственных между собой по общему селекционному предку, а именно китайской серой породе (1-я родословная), имеет более высокие воспроизводительные способности по сравнению с другими породами и группами пород. Полученные данные будут применяться в дальнейшей работе с целью совершенствования приемов сохранения генофонда малочисленных пород гусей. Ключевые слова: ГЕНОФОНД ПОРОД ГУСЕЙ, РОДСТВЕННЫЕ ГРУППЫ, РЕПРОДУКТИВНЫЕ КАЧЕСТВА, GENE POOL OF GEESE BREEDS, BIOGENETICALLY RELATED GROUPS OF BREEDS, REPRODUCTIVE PERFORMANCE

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ПРЕРЫВИСТОЕ ОСВЕЩЕНИЕ ПОВЫШАЕТ ЭФФЕКТИВНОСТЬ ИСКУССТВЕННОГО ОСЕМЕНЕНИЯ КУР В КЛЕТКАХ

10.33845/0033-3239-2019-68-7-8-51-55 ◽

2019 ◽

Keyword(s):

Reproductive Performance ◽

Artificial Insemination ◽

Egg Production ◽

Laying Hens ◽

Electric Energy ◽

Productive Performance ◽

Feed Conversion ◽

Scientific Center ◽

Academy Of Sciences ◽

Egg Fertility

Intermittent Lighting Improves the Efficiency of Artificial Insemination in Cage Housed Laying Hens Kavtarashvili A.Sh., Kolokolnikova T.N. Federal Scientific Center “All-Russian Research and Technological Poultry Institute” of Russian Academy of Sciences Omsk Agrarian Scientific Center Summary: The effects of different lighting regimes on the oviposition schedule, productive performance, and reproductive efficiency in cage housed laying hens of layer parental flock (Hisex White-R) were studied; the reasonable regime of artificial insemination (AI) under intermittent lighting is proposed. It was found that intermittent lighting regime 1L:4D:4L:1D:4L:10D compared to the constant lighting significantly alters oviposition schedule: under this regime 82.3% of all daily eggs were laid until 9 am (vs. 66.6% in control). This regime and AI at 10 am improved the productive and reproductive performance compared to control (constant lighting 16L:8D and AI at 12 am): mortality by 1.9%, egg production per initial hen by 3.8%, egg weight by 1.1%, percentage of eggs suitable for incubation by 1.9%, egg fertility by 0.9%, hatchability by 2.3%, hatch of chicks by 2.9%, feed conversion ratio (kg of feed per 10 eggs) by 5.3%, the expenses of electric energy for lighting (per 1000 eggs suitable for incubation) by 54.5%. Key words: INTERMITTENT LIGHTING, CAGE HOUSED LAYERS, ARTIFICIAL INSEMINATION (AI), OVIPOSITION SCHEDULE, AI TIMING, PRODUCTIVE PERFORMANCE, REPRODUCTIVE PERFORMANCE

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REPRODUCTIVE PERFORMANCE OF HAMSTERS WITH POLYACRYLAMIDE IMPLANTS CONTAINING ETHINYLOESTRADIOL

Acta Endocrinologica ◽

10.1530/acta.0.0700385 ◽

1972 ◽

Vol 70 (2) ◽

pp. 385-395 ◽

Cited By ~ 9

Author(s):

B. K. Davis ◽

I. Noske ◽

M. C. Chang

Keyword(s):

Reproductive Performance ◽

Mature Female ◽

Pregnancy Rates ◽

List Type ◽

Pathological Changes ◽

Apparent Effect ◽

Tissue Sections ◽

Main Target

ABSTRACT Mature female hamsters bearing subcutaneous polyacrylamide (PAA) implants, with ethinyloestradiol (EO), for at least 10 days prior to mating revealed: 0.5 and 2.5 mg EO in 7% PAA significantly disturb the timing of oestrus and mating, but have no apparent effect on rate of pregnancy, ovulation and implantation. 2.5 mg EO in 20 and 40% PAA conspicuously reduces the likelihood of pregnancy, although the occurrence of oestrus and mating are affected only slightly. Fertility in these hamsters was virtually restored, judging from pregnancy rates, when they were remated 11 days, or more, following removal of their implants (37 days after implantation), but significantly more foetuses were resorbed in these litters. From tissue sections of skin and muscle at the implant site, ovary, uterus, pituitary, adrenals and liver, PAA implants, without EO, cause no overt pathological changes in the bearer. Effects characteristic of oestrogen are present when these implants contain EO, and these include a conspicuous thickening of the epidermis and dermis; haemorrhagic lesions were also noted in the maternal placenta of animals with EO implants. There is an association between reproductive performance and the rate of EO release by an implant. A 7% PAA implant with 2.5 mg EO can release most of it within 2 days, and principally influences events (oestrus and mating) that precede the main target (pregnancy) of a 20% PAA implant, which releases the steroid over the longer interval of 7 days.

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