scholarly journals Investigation of Interacting Effects of Female Age, Laying Dates, and Egg Size in Yellow-eyed Penguins (Megadyptes antipodes)

The Auk ◽  
2002 ◽  
Vol 119 (4) ◽  
pp. 1137-1141 ◽  
Author(s):  
Melanie Massaro ◽  
John T. Darby ◽  
Lloyd S. Davis ◽  
Kerri-Anne Edge ◽  
Michael J. Hazel
Keyword(s):  
Egg Size ◽  
Annual Variation ◽  
Laying Date ◽  
Egg Volume ◽  
Female Age

Abstract Increased experience with age may allow long-lived seabirds to forage more efficiently and ultimately to invest more into reproduction. In many seabirds, egg size increases with female age, but declines with laying date. Declines in laying date might be due either to quality of individual females or females may adjust their egg size in response to poorer conditions typically found late in the season. We investigated the influence of female age, date of laying, and annual variation on egg size in Yellow-eyed Penguins (Megadyptes antipodes). Further, we tested whether there was an effect of individual females or female age on date of laying. Whereas female age influenced egg volume, mass, and width, laying date had no effect on egg size or mass in Yellow-eyed Penguins. Laying dates differed significantly among females but were not affected by their ages. These results indicate that in Yellow-eyed Penguins, some individual females lay consistently early or late, regardless of age, but that egg size generally increases with age.

scholarly journals Effects of Environmental Conditions and Parental Quality on Inter- and Intraclutch Egg-Size Variation in the Collared Flycatcher (Ficedula Albicollis)

The Auk ◽  
2005 ◽  
Vol 122 (2) ◽  
pp. 509-522 ◽  
Author(s):  
Rita Hargitai ◽  
János Török ◽  
László Tóth ◽  
Gergely Hegyi ◽  
Balázs Rosivall ◽  
...  
Keyword(s):  
Egg Size ◽  
Size Variation ◽  
Laying Date ◽  
Life History Trait ◽  
Ficedula Albicollis ◽  
Collared Flycatcher ◽  
Egg Formation ◽  
Adaptive Explanation ◽  
Breeding Condition

AbstractEgg size is a particularly important life-history trait mediating maternal influences on offspring phenotype. Females can vary their egg-size investment in relation to environmental circumstances, their own breeding condition, and the quality of their mate. Here we analyzed inter- and intraclutch variation in egg size in the Collared Flycatcher (Ficedula albicollis) on the basis of eight years of data. According to our results, mean egg size increased with female condition, but did not differ among young, middle-aged, and old females. The male’s age, body size, and forehead patch size did not influence egg size; thus, we found no evidence for differential investment in egg size in relation to male quality. We found no effect of laying date on egg size when controlling for ambient temperature during the egg formation period, yet temperature had a significant effect on egg size. That result indicates proximate constraints on egg formation. Furthermore, we report on annual differences in intraclutch egg-size variation. Egg size increased within clutches in years with a warm prelaying period; whereas in years when the weather during that period was cold, there was no significant intraclutch trend. Proximate considerations seem to explain the observed patterns of intraclutch egg-size variation; however, we cannot reject the adaptive explanation. Mean egg size and intraclutch egg-size variation were unrelated to clutch size. Therefore, we found no evidence for a trade-off between size and number of eggs within a clutch.

Annual variation in common eider egg size: effects of temperature, clutch size, laying date, and laying sequence

1995 ◽  
Vol 73 (9) ◽  
pp. 1579-1587 ◽  
Author(s):  
Gregory J. Robertson
Keyword(s):  
Clutch Size ◽  
Egg Size ◽  
Annual Variation ◽  
Size Variation ◽  
Egg Laying ◽  
Laying Date ◽  
Somateria Mollissima ◽  
Ambient Temperatures ◽  
Common Eiders ◽  
N 93

Annual variation in volumes of eggs laid by common eiders (Somateria mollissima sedentaria) nesting at La Pérouse Bay, Manitoba (58°43′N, 93°27′W), was studied over 3 years (1991–1993). Temperatures during the egg-laying period were higher in 1991 than in 1992 and 1993. However, the eiders began nesting in 1993 at the same time as in 1991, whereas in 1992 the eiders began laying approximately 2 weeks later. Eiders laid significantly smaller clutches in 1992 than in the other 2 years. Egg size did not correlate with clutch size or laying date in any year. However, eiders laid smaller eggs in 1992 and 1993 than in 1991. In five egg clutches, the pattern of intraclutch egg-size variation was different among years. The last laid eggs of five egg clutches were disproportionately smaller in 1992 and 1993 (cold years) than those laid in 1991. Minimum daily temperatures before the egg-laying period (during rapid yolk development) were positively correlated with egg size. However, this effect was not significant when year and egg sequence were controlled for. Egg-size variation was correlated with the overall ambient temperatures during the laying period, whereas annual clutch-size variation was correlated with laying date, suggesting that the proximate mechanisms affecting clutch and egg size are different.

The Role of Female Age in Determining Egg Size and Laying Date of Thick-Billed Murres

1997 ◽  
Vol 28 (4) ◽  
pp. 271 ◽  
Author(s):  
J. Mark Hipfner ◽  
Anthony J. Gaston ◽  
Leah N. de Forest
Keyword(s):  
Egg Size ◽  
Laying Date ◽  
Female Age

scholarly journals Laying Date, Chick Provisioning, and Breeding Success of Lesser Noddies on Aride Island, Seychelles

The Condor ◽  
2004 ◽  
Vol 106 (4) ◽  
pp. 887-895 ◽  
Author(s):  
Jaime A. Ramos ◽  
Anna Maria Maul ◽  
John Bowler ◽  
David Monticelli ◽  
Carlos Pacheco
Keyword(s):  
Breeding Success ◽  
Egg Size ◽  
Volume Index ◽  
Laying Date ◽  
Linear Growth Rate ◽  
Foraging Success ◽  
Egg Volume ◽  
Stochastic Variation ◽  
Fledging Success ◽  
Sterna Dougallii

Abstract We describe the main reproductive characteristics (laying date, egg size, hatchling mass, and breeding success), chick growth, and patterns of provisioning in Lesser Noddies (Anous tenuirostris) on Aride Island, Seychelles, 1995–2002. The bulk of the population laid eggs between late May and late June in most years. Both hatching and fledging success varied significantly between years, with fledging success (2–92%) more variable than hatching success (28–91%). Productivity of less than 0.10 chicks per breeding pair occurred in 25% of the years. In 2001, egg volume did not differ significantly between hatched and unhatched eggs. Chick mass at hatching was significantly correlated with an egg volume index, but there were no correlations between egg size and either hatching date or linear growth rate. Around 40% of the Lesser Noddy chicks were fed at dusk. Chicks aged 0–5 and 6–10 days received significantly less food than older chicks. There was evidence of daily and stochastic variation in the foraging success of individual birds. Comparing similar studies, chicks of Lesser Noddies and Sooty Terns (Sterna fuscata) appeared more resistant to fluctuating food supplies than those of Roseate Terns (Sterna dougallii), indicating that, in tropical seas, slow growth and foraging farther offshore are more advantageous than faster growth and inshore feeding. Datas de Postura, Alimentação dos Filhotes e Sucesso Reprodutivo de Anous tenuirostris na Ilha de Aride, Seychelles Resumo. Neste estudo descrevemos as principais características da biologia reprodutiva (datas de postura, tamanho dos ovos, peso dos filhotes ao nascerem e sucesso reprodutivo), crescimento e padrões de alimentação dos filhotes em Tinhosa-de-barrete, Anous tenuirostris, na ilha de Aride, Seychelles, 1995–2002. Na maioria dos anos a postura ocorreu entre o fim de Maio e o fim de Junho. O sucesso de eclosão e o sucesso de sobrevivência das crias variaram significativamente entre anos, apresentando o sucesso de sobrevivência (2–92%) uma maior variação do que o sucesso de eclosão (28–91%). Uma produtividade inferior a 0,10 crias por casal reprodutor ocorreu em 25% dos anos. Em 2001, o volume dos ovos que eclodiram não diferiu significativamente do volume dos ovos que não eclodiram. O peso dos filhotes ao nascerem apresentou uma correlação significativa com o índice de volume dos ovos, mas não se obtiveram correlações entre o tamanho dos ovos e, a data de eclosão e a taxa de crescimento linear dos filhotes. Cerca de 40% dos filhotes de Tinhosa-de-barrete foram alimentados ao anoitecer. Os filhotes com idades entre 0–5 e 6–10 dias receberam significativamente menos alimento do que os filhotes mais velhos. Foram observadas variações diárias e estocásticas no sucesso de alimentação dos indivíduos. A comparação do presente estudo com estudos semelhantes, sugere que as crias de A. tenuirostris e de Sterna fuscata sejam mais resistentes a flutuações na disponibilidade de alimento do que as crias de Sterna dougallii. Isto indica que, em mares tropicais, uma menor taxa de crescimento e uma alimentação em zonas pelágicas são estratégias mais vantajosas do que uma taxa de crescimento rápida e alimentação em zonas costeiras.

ASSECSSING MOCA TEST IN SUBACUTE STROKE PATIENTS AND COMPARE MOCA VERSUS MMSE

2016 ◽  
pp. 120-127
Author(s):  
Dinh Toan Nguyen
Keyword(s):  
Human Life ◽  
Statistical Significance ◽  
High Sensitivity ◽  
Stroke Patients ◽  
Cross Sectional ◽  
Female Age ◽  
Subacute Stroke ◽  
Duration Of Illness ◽  
Dsm Iv

Background: Dementia after stroke, particularly subacute period is often overlooked. Today the quality of human life is increasingly high, finding scales that have high value for detection of dementia in patients with stroke is increasingly interested. MoCA test is high sensitivity with mild dementia and identify more abnormalities of awareness caused by vascular, but MoCA have not been studied much in Vietnam. Objective: Assessing MoCA test in subacute stroke patients and compare MoCA versus MMSE in these patients. Subjects: 90 patients with subacute stroke period, these people are being treated at Department of cardiovascular internal medicine at Hue Central Hospital, from 7/2014 - 7/2015. Methods: cross-sectional description and analysis. Results: The mean age is 65.57 ± 13.38, accounting for 54.4% male and 45.6% female. Age, duration of illness has weak correlation with MoCA. The risk factors: hypertension, stroke ischemic transient, alcoholism, smoking, heart disease, diabetes, dyslipidemia related no statistical significance with MoCA. The proportion of dementia in subacute stroke according MoCA is 82.2%. The concordance between MoCA and MMSE was good (kappa = 0.684). Using DSM-IV criteria as the gold standard we found MoCA more valuable in the dementia diagnosis than MMSE (AUC 0.864 versus 0.774, p <0.05). Conclusion: The rate of dementia in stroke subacute period according MoCA is quite high. MoCA is valuable than MMSE in detecting dementia in patients with stroke subacute period, this scale is short, easy to implement so should put into using widely in clinical practice. Key words: MoCA test, subacute stroke, dementia

P–774 Clinical effectiveness of elective single versus double blastocyst transfer in women aged 36 years or older

2021 ◽  
Vol 36 (Supplement_1) ◽  
Author(s):  
H Cai ◽  
B W Mol ◽  
S Gordts ◽  
H Wang ◽  
J Shi
Keyword(s):  
Statistical Significance ◽  
Age Groups ◽  
Clinical Effectiveness ◽  
Blastocyst Transfer ◽  
P Value ◽  
Multiple Gestation ◽  
Multiple Pregnancies ◽  
Morphological Examination ◽  
Female Age

Abstract Study question If the elective single-blastocyst transfer (eSBT) strategy can be applied to women aged 36 or older. Summary answer In women ≥36 years old with at least two blastocysts, eSBT increased cumulative livebirth rate (LBR) while minimizing twins compared with double blastocyst transfer (DBT). What is known already: In young women with a good prognosis, eSBT policy is an accepted strategy to maintain LBR while decreasing multiple gestation. However, in many areas of the world DBT is still applied in older women. Study design, size, duration We performed a retrospective cohort study of 429 women aged ≥36 years or older who received IVF ovarian stimulation cycles between Jan 2015 and Oct 2018 and who had at least two blastocysts. Women were followed up until Oct 2020 for their fertility outcomes including cumulative live birth and multiple pregnancies. The study was performed at the Northwest Women and Children’s Hospital, Xi’an, China. Participants/materials, setting, methods Out of 429 women, 240 underwent a fresh cycle of eSBT and 189 DBT. The subsequent frozen-thawed embryo transfer cycles were a combination of single- and double- blastocyst transfers, more commonly the latter. Analysis was stratified for patients in age groups 36–37, 38–39 and ≥40 and quality of the blastocyst transferred, as graded by morphological examination. Outcomes were the LBR in the fresh cycle, cumulative LBR and multiple rate after fresh and frozen embryo transfers. Main results and the role of chance The cumulative LBR was 74.2% (178/240) for eSBT versus 63.0% (119/189) for DBT (OR = 1.69, 95%CI 1.12–2.56), irrespective of female age. The multiple rate was 9% (16/178) after eSBT versus 29.4% (35/119) after DBT (P- value &lt; .001). The total number of children born was 194 after eSBT versus 154 after DBT. Stratified by female age, the cumulative LBRs in women aged 36–37 (78.9 vs 70.5%), 38–39 (68.9 and 61.1%) and ≥ 40 years (59.3 and 47.5%), were higher after eSBT compared with DBT, however, the differences did not reach statistical significance in each subgroups. LBRs in the fresh cycles were comparable for patients with eSBT compared with DBT (52.1% vs. 52.4%, OR = 0.99, 95%CI 0.68–1.45). In women &lt; 40 years, DBT resulted in a small non-significant increase in LBR in the fresh transfer (63.2% vs. 61.2%, 95%CI=0.64–1.85, 36–37 years; 48.1% vs. 41.0%, 95%CI=0.64–2.80, 38–39 years) at the expense of a marked increase in twinning rate (0–5.4% vs. 31.7–34.6%). For women ≥40 years, no significant differences were observed in the LBR (37.0% vs 45%, 95%CI 0.47–4.07) or twinning rate (0 vs 7.7%) between eSBT and DBT group. The findings persisted with and without accounting for quality of the blastocyst transferred. Limitations, reasons for caution This study is limited by its observational character. Wider implications of the findings: In women ≥36 years with two blastocysts, eSBT should be the preferred treatment which maximizes the cumulative LBR for a decrease in the rate of multiple pregnancies. Trial registration number Not applicable

scholarly journals Nest Survival Patterns in Willow Ptarmigan: Influence of Time, Nesting Stage, and Female Characteristics

The Condor ◽  
2007 ◽  
Vol 109 (2) ◽  
pp. 377-388 ◽  
Author(s):  
Scott Wilson ◽  
Kathy Martin ◽  
Susan J. Hannon
Keyword(s):  
British Columbia ◽  
Annual Variation ◽  
Nest Survival ◽  
Bird Species ◽  
Ecological Factors ◽  
Individual Characteristics ◽  
Willow Ptarmigan ◽  
Female Age ◽  
Daily Nest Survival ◽  
Survival Patterns

Abstract Nest predation is the most important factor limiting reproductive success of Willow Ptarmigan (Lagopus lagopus), as it is for many bird species. Using program MARK, we examined patterns of daily nest survival in two widely separated populations of Willow Ptarmigan in Manitoba and British Columbia, Canada, by examining variation among years, over the course of the breeding season or in relation to the age of the nest, or age and condition of the female. At La Pérouse Bay, Manitoba, daily nest survival increased linearly throughout the season, with moderate annual variation. Nests also had higher daily survival during laying and late in incubation, and lower survival early in incubation. At Chilkat Pass, British Columbia, daily nest survival varied strongly by year and nests had higher survival early and late in the season, but survival was not affected by the age of the nest. At both sites, but especially at Chilkat Pass, periods of lower nest survival tended to coincide with peak breeding periods, suggesting predators may adjust their search effort based on the likelihood of locating nests. Neither female age nor condition were included in the best models. Thus, in both ptarmigan populations, nest survival patterns appeared to be influenced more by ecological factors than by individual characteristics of breeding females. The extent of annual variation and seasonal patterns may have differed between sites due to the different predator and alternative prey communities.

STUDIES ON THE USE OF FABA BEANS IN RATIONS FOR LAYING HENS

1977 ◽  
Vol 57 (3) ◽  
pp. 421-425 ◽  
Author(s):  
A. R. ROBBLEE ◽  
D. R. CLANDININ ◽  
R. T. HARDIN ◽  
G. R. MILNE ◽  
K. DARLINGTON
Keyword(s):  
Egg Production ◽  
Egg Size ◽  
Production Efficiency ◽  
White Leghorn ◽  
Feed Conversion ◽  
Considerable Decrease ◽  
Large Size ◽  
Vicia Faba L ◽  
Faba Beans

In two experiments, White Leghorn pullets kept in batteries were fed rations containing 0, 5, 10, 15, 20 or 30% raw faba beans (Vicia faba L.) for 336 days. The rations were designed to be isocaloric, isonitrogenous and to have equal levels of methionine plus cystine. The results obtained indicated that levels up to and including 20% faba beans in ration ssupplemented with methionine had no adverse effect on mortality, rate of egg production, efficiency of feed conversion or body weight. A level of 30% faba beans resulted in increased mortality, and decreased egg production and feed conversion in one experiment but had no effect in the other. Egg size tended to decrease as the level of faba beans in the ration increased, resulting in a considerable decrease in the percentage of "large size" eggs graded according to Canadian standards. There was an increase in interior quality of the eggs as measured by Haugh units as the level of faba beans used increased. Specific gravity of the eggs was not affected by use of faba beans in the rations.

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