Age and experience affect the reproductive success of captive Loggerhead Shrike (Lanius ludovicianus) subspecies

2017 ◽  
Vol 95 (8) ◽  
pp. 547-554 ◽  
Author(s):  
T.L. Imlay ◽  
J.C. Steiner ◽  
D.M. Bird
Keyword(s):  
Reproductive Success ◽  
Wild Population ◽  
Trade Offs ◽  
Age Related ◽  
Captive Populations ◽  
Experienced Male ◽  
Lanius Ludovicianus ◽  
Fledgling Success ◽  
Loggerhead Shrike ◽  
Effect Of Age

Two explanations are often used to interpret the positive relationship between reproductive success and age: (1) trade-offs between current and future breeding and (2) age-related improvements in competence. Captive populations provide a unique opportunity to test these explanations because several mechanisms that result in age-related improvements in competence are managed. We modelled the effect of age and experience on the reproductive success of captive migrant Loggerhead Shrike (Lanius ludovicianus L., 1766) subspecies (formerly Lanius ludovicianus migrans W. Palmer, 1898). Female shrikes had the highest reproductive success during mid-life and lower success at 1–2 years of age and over 10 years. Both experienced male and female shrikes had higher fledgling success than inexperienced individuals. Although captive populations breed in controlled settings with few limitations, this work suggests that both explanations (i.e., trade-offs and age-related improvements in competence) are important for understanding reproductive success. Furthermore, management of the captive shrike population can be informed by these relationships to maximize the number of young produced for release to supplement the wild population.

scholarly journals Higher sociability leads to lower reproductive success in female kangaroos

2020 ◽  
Vol 7 (8) ◽  
pp. 200950
Author(s):  
C. S. Menz ◽  
A. J. Carter ◽  
E. C. Best ◽  
N. J. Freeman ◽  
R. G. Dwyer ◽  
...  
Keyword(s):  
Reproductive Success ◽  
Social Relationships ◽  
Wild Population ◽  
Social Bonds ◽  
Group Living ◽  
Trade Offs ◽  
Fitness Consequences ◽  
Living Species ◽  
Complex Forms ◽  
First Time

In social mammals, social integration is generally assumed to improve females' reproductive success. Most species demonstrating this relationship exhibit complex forms of social bonds and interactions. However, female eastern grey kangaroos ( Macropus giganteus ) exhibit differentiated social relationships, yet do not appear to cooperate directly. It is unclear what the fitness consequences of such sociability could be in species that do not exhibit obvious forms of cooperation. Using 4 years of life history, spatial and social data from a wild population of approximately 200 individually recognizable female eastern grey kangaroos, we tested whether higher levels of sociability are associated with greater reproductive success. Contrary to expectations, we found that the size of a female's social network, her numbers of preferential associations with other females and her group sizes all negatively influenced her reproductive success. These factors influenced the survival of dependent young that had left the pouch rather than those that were still in the pouch. We also show that primiparous females (first-time breeders) were less likely to have surviving young. Our findings suggest that social bonds are not always beneficial for reproductive success in group-living species, and that female kangaroos may experience trade-offs between successfully rearing young and maintaining affiliative relationships.

scholarly journals Ageing and senescence across reproductive traits and survival in superb fairy-wrens (Malurus cyaneus)

2019 ◽  
Author(s):  
Eve Cooper ◽  
Timothée Bonnet ◽  
Helen Osmond ◽  
Andrew Cockburn ◽  
Loeske E. B. Kruuk
Keyword(s):  
Life History ◽  
Reproductive Success ◽  
Age Of Onset ◽  
Reproductive Traits ◽  
Individual Variability ◽  
Multiple Traits ◽  
Long Term Study ◽  
Trade Offs ◽  
Age Related ◽  
Malurus Cyaneus

Why do senescence rates of fitness-related traits often vary dramatically? By considering the full ageing trajectories of multiple traits we can better understand how trade-offs and life-history shapes the unique evolution of senescence rates within a population. Here, we examine age-related changes in survival and six reproductive traits in both sexes using a long-term study of a wild population of a cooperatively-breeding songbird, the superb fairy-wren (Malurus cyaneus). We compare ageing patterns between traits by estimating standardized rates of maturation, the age of onset of senescence and rates of senescence, while controlling for confounding factors reflecting individual variability in life-history. We found striking differences in ageing and senescence patterns between survival and reproduction, and between the sexes. In both sexes, rates of survival started to decline from maturity onwards. In contrast, all reproductive traits showed improvements into early adulthood and many showed little or no evidence of senescence. Male reproductive ageing appeared to be driven by sexual selection, with extra-group reproductive success and sexually-selected plumage phenology showing much greater change with age than did within-group reproductive success. We discuss how the superb fairy-wrens’ complex life history may contribute to the disparate ageing patterns in this species.

scholarly journals Scotopic thresholds on dark-adapted chromatic perimetry in healthy aging and age-related macular degeneration

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Manjot Kaur Grewal ◽  
Shruti Chandra ◽  
Alan Bird ◽  
Glen Jeffery ◽  
Sobha Sivaprasad
Keyword(s):  
Macular Degeneration ◽  
Healthy Aging ◽  
Intraclass Correlation ◽  
Age Related Macular Degeneration ◽  
Healthy Individuals ◽  
Age Related ◽  
Rod Function ◽  
The Mean ◽  
Highly Correlated ◽  
Effect Of Age

AbstractTo evaluate the effect of aging, intra- and intersession repeatability and regional scotopic sensitivities in healthy and age-related macular degeneration (AMD) eyes. Intra- and intersession agreement and effect of age was measured in healthy individuals. The mean sensitivity (MS) and pointwise retinal sensitivities (PWS) within the central 24° with 505 nm (cyan) and 625 nm (red) stimuli were evaluated in 50 individuals (11 healthy and 39 AMD eyes). The overall intra- and intersession had excellent reliability (intraclass correlation coefficient, ICC > 0.90) and tests were highly correlated (Spearman rs = 0.75–0.86). Eyes with subretinal drusenoid deposit (SDD) had reduced PWS centrally, particularly at inferior and nasal retinal locations compared with controls and intermediate AMD (iAMD) without SDD. There was no difference in MS or PWS at any retinal location between iAMD without SDD and healthy individuals nor between iAMD with SDD and non-foveal atrophic AMD groups. Eyes with SDD have reduced rod function compared to iAMD without SDD and healthy eyes, but similar to eyes with non-foveal atrophy. Our results highlight rod dysfunction is not directly correlated with drusen load and SDD location.

scholarly journals The effect of age on postural and cognitive task performance while using vibrotactile feedback

2015 ◽  
Vol 113 (7) ◽  
pp. 2127-2136 ◽  
Author(s):  
Chia-Cheng Lin ◽  
Susan L. Whitney ◽  
Patrick J. Loughlin ◽  
Joseph M. Furman ◽  
Mark S. Redfern ◽  
...  
Keyword(s):  
Older Adults ◽  
Cognitive Performance ◽  
Center Of Pressure ◽  
Cognitive Task ◽  
Balance Performance ◽  
Vibrotactile Feedback ◽  
Younger Adults ◽  
Age Related ◽  
Trunk Tilt ◽  
Effect Of Age

Vibrotactile feedback (VTF) has been shown to improve balance performance in healthy people and people with vestibular disorders in a single-task experimental condition. It is unclear how age-related changes in balance affect the ability to use VTF and if there are different attentional requirements for old and young adults when using VTF. Twenty younger and 20 older subjects participated in this two-visit study to examine the effect of age, VTF, sensory condition, cognitive task, duration of time, and visit on postural and cognitive performance. Postural performance outcome measures included root mean square of center of pressure (COP) and trunk tilt, and cognitive performance was assessed using the reaction time (RT) from an auditory choice RT task. The results showed that compared with younger adults, older adults had an increase in COP in fixed platform conditions when using VTF, although they were able to reduce COP during sway-referenced platform conditions. Older adults also did not benefit fully from using VTF in their first session. The RTs for the secondary cognitive tasks increased significantly while using the VTF in both younger and older adults. Older adults had a larger increase compared with younger adults, suggesting that greater attentional demands were required in older adults when using VTF information. Future training protocols for VTF should take into consideration the effect of aging.

Can Regression Discontinuity Help Answer an Age-Old Question in Education? The Effect of Age on Elementary and Secondary School Achievement

2009 ◽  
Vol 9 (1) ◽  
Author(s):  
Justin Smith
Keyword(s):  
Secondary School ◽  
Low Income ◽  
School Achievement ◽  
School Outcomes ◽  
Older Students ◽  
Low Income Students ◽  
Age Related ◽  
Writing Tests ◽  
Effect Of Age ◽  
Related Skill

Abstract Single-date school entry systems create large age differences between children in the same grade. Older students have been shown in the literature to outperform younger students along many elementary school outcomes, and some post-schooling outcomes. Little evidence exists about the size of these advantages in high school. Data from British Columbia, Canada are used to estimate the effect of age on test scores in grades 4, 7, and 10. I estimate that older students still have a sizable skill advantage in grade 10 across numeracy, reading, and writing tests. The advantage is strongest for girls and low-income students. The results suggest a certain degree of permanence to age related skill differences, which may spill over and affect adult outcomes.

scholarly journals Effects of Age, Gender, and Menopausal Status on Small Dense Low-Density Lipoprotein Cholesterol and Low-Density Lipoprotein Cholesterol Fractions; JMS-II Cohort Study

2020 ◽  
Author(s):  
Toshihide Izumida ◽  
Yosikazu Nakamura ◽  
Yukihiro Sato ◽  
Shizukiyo Ishikawa
Keyword(s):  
Cohort Study ◽  
Postmenopausal Women ◽  
Low Density Lipoprotein ◽  
Menopausal Status ◽  
Density Lipoprotein ◽  
Lipoprotein Cholesterol ◽  
Low Density ◽  
Low Density Lipoprotein Cholesterol ◽  
Age Related ◽  
Effect Of Age

Abstract Background:Small dense low-density lipoprotein cholesterol (sdLDL-C) might be a better cardiovascular disease (CVD) indicator than low-density lipoprotein cholesterol (LDL-C); however, details regarding its epidemiology remain elusive. The present study aimed at evaluating the effect of age, gender, and menopausal status on sdLDL-C levels and sdLDL-C/LDL-C ratio in the Japanese population.Methods:We examined the baseline cross-sectional data from the Jichi Medical School-II Cohort Study, including 5,208 participants (2,397 men and 2,811 women). To assess age-related trends, the sdLDL-C and sdLDL-C/LDL-C ratios were plotted against gender. We evaluated the effect of age and menopausal status using multiple linear regression analysis.Results:We observed that in men, the sdLDL-C levels and sdLDL-C/LDL-C ratio increased during younger adulthood, peaked at 50–54 years, and then decreased. In women, we observed relatively regular increasing trends of sdLDL-C level and sdLDL-C/LDL-C ratio until approximately 65 years, followed by a downward or pleated trend. The crossover of sdLDL-C levels for the genders occurred at 70–74 years, but we could not observe any sdLDL-C/LDL-C ratio crossover. Standardized sdLDL-C levels and sdLDL-C/LDL-C ratio in 50-year old men, premenopausal women, and postmenopausal women were 26.6, 22.7, and 27.4 mg/dL and 0.24, 0.15, and 0.23, respectively. The differences between premenopausal and postmenopausal women were significant (P<0.001).Conclusions:sdLDL-C and sdLDL-C/LDL-C ratios show different distributions by age, gender, and menopausal status with trends different from other lipids. A subgroup-specific approach would be necessary to implement sdLDL-C for CVD prevention strategies, fully considering age-related trends, gender differences, and menopausal status.

scholarly journals Age-related influences on somatic and physical fitness of elite police agents (Influencias de la edad en la aptitud física y somática de los agentes de policía de élite)

Retos ◽  
2020 ◽  
pp. 281-288
Author(s):  
Alfredo O. Araujo ◽  
Jose M. Cancela ◽  
Pedro Bezerra ◽  
Cesar Chaves ◽  
Luis P. Rodrigues
Keyword(s):  
Physical Fitness ◽  
Police Officers ◽  
Bench Press ◽  
Aerobic Power ◽  
Handgrip Strength ◽  
Squat Jump ◽  
Age Related ◽  
Grasa Corporal ◽  
Endurance Strength ◽  
Effect Of Age

Age-related influences on somatic and physical fitness of elite police agents Influencias de la edad en la aptitud física y somática de los agentes de policía de élite Background: Elite police officers must be physically fit to perform their job occupational demands but information on the effect of age in their physical fitness and somatic composition is scarce. Our aim is to describe the effect of age on somatic and physical fitness of a Special Police Unit (SPU); and to understand age-related changes. Methods: 117 SPU elements of a total of 218, aged 42.6±4.2 years, were assessed on their somatic (height, weight, circumferences, skinfolds); body composition (BMI, body fat); and physical fitness (maximal, power and endurance strength, aerobic power, and flexibility). T-tests were used for comparing results to other police studies. Regression analysis was used to detect the effect of age for somatic and fitness variable. Results: SPU elements showed a homogeneous and suitable fitness condition. No somatic differences were found along age, but annual age losses were found for physical fitness, namely for strength: left handgrip strength (95%CI -0.70 to -0.12), bench press (95%CI -2.34 to -0.89), squat jump (95%CI -0.70 to -0.12), medicinal ball throw (95%CI -0.62 to -0.25), push-ups (95%CI -1.64 to -0.66), pull-ups (95%CI -0.53 to -0.11), sit-ups (95%CI -1.33 to -0.27), but also on the VO2max (-0.535 to -0.115). Conclusions: Portuguese SPU elements showed a good somatic and physical fitness condition according to the requirements of their profession. Regardless the effect of age they were able to maintain a good somatic fitness and a very good aerobic power along the years. The loss of strength was the most associated with age.  Resumen. Introducción: Los agentes de policía de élite deben estar en buena forma física para cumplir con las demandas ocupacionales de su trabajo, pero la información sobre el efecto de la edad en su condición física y composición somática es escasa. Nuestro objetivo es describir el efecto de la edad sobre la aptitud física y somática de una Unidad Especial de Policía (SPU); y comprender los cambios relacionados con la edad. Métodos: Se evaluaron 117 elementos SPU de un total de 218, con edad de 42,6 ± 4,2 años, en su morfología (altura, peso, circunferencias, pliegues cutáneos); composición corporal (IMC, grasa corporal); y aptitud física (fuerza máxima, potencia y resistencia, potencia aeróbica y flexibilidad). Se utilizaron pruebas t-Student para comparar los resultados con otros estudios policiales. Se utilizó el análisis de regresión para detectar el efecto de la edad para la variable somática y de aptitud. Resultados: Los elementos SPU mostraron una condición física adecuada y homogénea. No se encontraron diferencias somáticas a lo largo de la edad, pero se encontraron pérdidas de edad anuales para la condición física, es decir, para la fuerza: fuerza de prensión (IC 95%: -0,70 a -0,12), bench press (IC del 95%: -2,34 a -0,89), squat jump (IC 95%: -0,70 a -0,12), lanzamiento de pelota medicinal (IC 95%: -0,62 a -0,25), extensiones de brazo (IC 95%: -1,64 a -0,66), flexiones de brazo (IC 95%: -0,53 a -0,11), abdominales (IC 95%: -1,33 a -0,27), pero también sobre el VO2 máx. (-0,535 a -0,115). Conclusiones: Los elementos SPU portugueses mostraron una buena condición física y somática de acuerdo con los requisitos de su profesión. Independientemente del efecto de la edad lograron mantener una buena condición somática y una muy buena potencia aeróbica a lo largo de los años. La pérdida de fuerza fue la más asociada con la edad.

scholarly journals “Important Players” in the Development of Age-Related Cataracts (Literature Review)

2019 ◽  
Vol 16 (1S) ◽  
pp. 21-26
Author(s):  
G. Z. Israfilova
Keyword(s):  
Literature Review ◽  
Poor Vision ◽  
Asian Populations ◽  
Age Related ◽  
Increased Risk ◽  
The World ◽  
Lens Opacities ◽  
Somatic Diseases ◽  
Effect Of Age ◽  
Gender Features

Millions people around the world, especially in old age, lose sight because of cataracts. The age-related cataract affects approximately 37 million people in the world annually, and in 51 % of cases, it is the cause of poor vision. Relevant is the importance of identifying risk factors for the development of age-related cataracts. This literature review is devoted to studies examining the influence of various factors on the development of lens opacities. The paper presents data on the effect of age on the development of age-related cataracts, so the prevalence of cataracts at the age of 52–62 years is 5 %, at the age of 60–69 years — 30 %, at the age of 70 and older — 64 %. Its gender features are highlighted — the frequency of lens opacities in women increases significantly with age, and its appearance coincides with the appearance of estrogen deficiency in menopause. Reflected literature data on the dependence of cataract prevalence on race (revealed a higher prevalence in various Asian populations compared with the population of Western countries). This review also had showed the influence of lifestyle and bad habits on the occurrence of cataracts. It was found that smokers have an increased risk of occurrence of a nuclear cataract and, to a lesser extent, the development of its cortical type. It is noted that the development of lens opacification is also influenced by the amount of alcohol consumed, increasing the risk of cataracts, so when studying individual types of cataracts, it is shown that the consumption of strong drinks and wine is associated with an increased risk of nuclear cloudiness. Presents data from large cohort studies that compare (using odds ratios and confidence intervals) the association of cataracts with such somatic diseases as diabetes mellitus, hypertension, also with body mass index and some medications.

Drug Intolerance: Age Related Aspects

2021 ◽  
Author(s):  
Maria Grakhova ◽  
Olga Rychkova ◽  
Anastasia Braun ◽  
Almira Sagitova ◽  
Maria Nesterova
Keyword(s):  
Ace Inhibitors ◽  
Clinical Manifestations ◽  
The Other ◽  
Drug Intolerance ◽  
Age Related ◽  
Life Threatening ◽  
Group 3 ◽  
Dichotomous Variables ◽  
Pathological Reaction ◽  
Effect Of Age

Aim: Identification of age-specific drug intolerance. Materials and methods: The study was conducted over the period from 2017 to 2020 and included 200 outpatient medical history forms of people diagnosed as having an unspecified pathological reaction to a drug or medication. All drug reactions are reported by patients own statements and were allocated to dichotomous variables. The results were analyzed by nonparametric statistics. Results: Three groups of patients: 18-44 years (n=49); 45-60 years (n=60); 61 and over (n=91). The odds of incomprehensible reactions were 2.2 times higher in patients in group 3 than in patients in the other groups. Group 3 patients were 12 times more likely to have an itchy reaction to medications than patients in the other groups. Group 1 patients were 3 times more likely to have urticaria than patients in groups 2 and 3. The odds of drug intolerance to ACE inhibitors were 2.6 times higher in group 3 patients than in patients in other groups. When comparing clinical manifestations of drug intolerance to penicillin- and cephalosporin-type antibiotics, no significant differences were found in all patients. The presence of allergies and somatic pathology of 3 or more systems did not significantly affect the possibility of reactions of varying severity to 3 or more drugs in these groups. Conclusions: Patients age has no effect on the possibility of reactions to certain groups of drugs. The exception was ACE inhibitors, which is most likely due to the higher frequency of prescribing antihypertensive therapy in patients in this age group. The aggravation of clinical manifestations and the occurrence of polypharmacy are not associated with age and comorbid background. It should be noted that correlation between age and non-life-threatening clinical manifestations of drug intolerance was revealed, which indicates the absence of reliable effect of age on the possibility of anaphylactic shock or angioedema.

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