scholarly journals Antler development in reindeer in relation to age and sex

Rangifer ◽  
2002 ◽  
Vol 22 (1) ◽  
pp. 75 ◽  
Author(s):  
Amund Høymork ◽  
Eigil Reimers
Keyword(s):  
Field Study ◽  
Rangifer Tarandus ◽  
Sex Discrimination ◽  
Male And Female ◽  
Adult Females ◽  
Antler Size ◽  
Free Ranging ◽  
Suggested Classification ◽  
Age And Sex ◽  
Antler Development

Yearling male and adult female reindeer (Rangifer tarandus tarandus) are similar in size and shape. If sexual clues are hidden, it can be difficult to distinguish between them. Antlers can be a useful aid in classifying yearling males and adult females, depending on whether specific antler characteristics are identifiable for these two groups. We recorded antler characteristics in a domestic reindeer herd (Vågå) and found considerable overlap in antler height, width and circumference between the different age and sex groups. Total tines and number of tine split-offs are use¬ful for the field biologist when discriminating among adult females, yearling males and 2.5 year-old males. For example, when using the tine split-offs with the suggested classification, 79% of the observed adult females and 76% of the yearling males were classified correctly. The antler height, width and circumference provide other biological dif¬ferences between groups, but are not easy to use to identify free ranging reindeer. This is due to the great overlap in antler size between the groups and measuring difficulties in a field study situation. Male and female calves have very similar antlers, and only the antler width is possible for sex discrimination, giving 67% accuracy of discriminating between these two groups.

Lifetime patterns in adult female mass, reproduction, and offspring mass in semidomestic reindeer (Rangifer tarandus tarandus)

2002 ◽  
Vol 80 (12) ◽  
pp. 2047-2055 ◽  
Author(s):  
Lars Rönnegård ◽  
Pär Forslund ◽  
Öje Danell
Keyword(s):  
Rangifer Tarandus ◽  
Regression Coefficient ◽  
Average Difference ◽  
Male And Female ◽  
Older Mothers ◽  
Adult Females ◽  
Rangifer Tarandus Tarandus ◽  
Mass Reproduction ◽  
The Difference ◽  
Old Females

The objective of our investigation was to examine relationships between lifetime patterns of female mass, calving incidence, and offspring mass in semidomestic reindeer (Rangifer tarandus tarandus). The analyses were made on data recorded from 1986 to 1997 on semidomestic reindeer in the herding district of Ruvhten Sijte in Sweden. A female rearing a calf was shown to weigh 3.1 ± 0.3 kg (mean ± SE) less in winter than a female not rearing a calf. The difference in calving incidence between females rearing a calf in the previous year and those not rearing a calf in the previous year was small, but there was a tendency for old females to have a decreased calving incidence if they had reared a calf in the previous year. The average calving percentage for adult females was 73%. Calf masses were affected by both the mother's mass and her age. The regression coefficient of calf autumn mass on female mass the previous winter was 0.26 ± 0.02. Mothers aged 2–4 years had calves that weighed less than calves of older mothers. The average difference in autumn mass between male and female calves was 2.9 ± 0.2 kg, but the difference was less for calves with mothers aged 2–4 years. We obtained lifetime patterns of female mass, calving incidence, and offspring mass. We also gave an organized structure of relationships between these traits.

The Neurobiology of Pain

2019 ◽  
pp. 387-414
Author(s):  
Maria Fitzgerald ◽  
Michael W. Salter
Keyword(s):  
Early Life ◽  
Pain Perception ◽  
Long Term Effects ◽  
Male And Female ◽  
Functional Changes ◽  
Pain Pathways ◽  
Developmental Age ◽  
Short And Long Term ◽  
Age And Sex

The influence of development and sex on pain perception has long been recognized but only recently has it become clear that this is due to specific differences in underlying pain neurobiology. This chapter summarizes the evidence for mechanistic differences in male and female pain biology and for functional changes in pain pathways through infancy, adolescence, and adulthood. It describes how both developmental age and sex determine peripheral nociception, spinal and brainstem processing, brain networks, and neuroimmune pathways in pain. Finally, the chapter discusses emerging evidence for interactions between sex and development and the importance of sex in the short- and long-term effects of early life pain.

scholarly journals GENETIC LINKAGE IN THE HORSE. II. DISTRIBUTION OF MALE RECOMBINATION ESTIMATES AND THE INFLUENCE OF AGE, BREED AND SEX ON RECOMBINATION FREQUENCY

Genetics ◽  
1984 ◽  
Vol 106 (1) ◽  
pp. 109-122
Author(s):  
Leif Andersson ◽  
Kaj Sandberg
Keyword(s):  
Genetic Linkage ◽  
Recombination Frequency ◽  
Age Effect ◽  
Significant Heterogeneity ◽  
Male Recombination ◽  
Male And Female ◽  
Factors Affecting ◽  
Individual Male ◽  
Breed Differences ◽  
Age And Sex

ABSTRACT n the present study an extensive amount of data, comprising more than 30,000 offspring in total, was analyzed to evaluate the influence of age and sex on the recombination frequency in the K-PGD segment of the equine linkage group (LG) I and the influence of age, breed and sex on recombination in the Al-Es segment of LG II. A highly significant sex difference is reported for both segments. Male and female recombination values in the K-PGD segment were estimated at 25.8 ± 0.8 and 33.3 ± 2.5%, respectively. Similarly, recombination was less frequent in the male (36.6 ± 0.7%) than in the female (46.6 ± 1.2%) in the Al-Es segment. Comparison of data from two Swedish horse breeds revealed no significant breed differences in either sex for recombination in the Al-Es segment. No evidence of an age effect was found in any segment or sex. The distribution of individual male recombination estimates was also investigated, and a significant heterogeneity among stallions was revealed in the K-PGD segment. The results are discussed in relation to previous studies on factors affecting recombination in mammals.

scholarly journals Check This One out: Analyzing Slang Usage among Iranian Male and Female Teenagers

2011 ◽  
Vol 4 (2) ◽  
pp. 198 ◽  
Author(s):  
Sara Hashemi Shahraki ◽  
Abbass Eslami Rasekh
Keyword(s):  
High School ◽  
High School Students ◽  
Age Groups ◽  
School Students ◽  
Chi Square ◽  
Male And Female ◽  
The Social ◽  
Completion Test ◽  
Female Teenagers ◽  
Age And Sex

Slang usage in modern age Iran is a popular phenomenon among most male and female teenagers. How pervasive this variation of language use is among various age and sex groups in Iran has been a question of debate given the significance of religion in a theological system of social structure. The work presented in this study aims to investigate the effect of age and sex on variability of slang usage. Sixty Iranian participants were selected, and then were divided into three age groups (i.e. primary school, high school, and senior university students) each group consisting of ten males and ten females. A self-made questionnaire in the form of Discourse Completion Test (DCT) describing nine situations of friendly conversations was given to the participants. They were asked to make their choice on the responses, which ranged from formal to very informal style (common teenage slang expressions), or to write down what they wish to say under each circumstance. The results of the chi–square tests indicated that slang usage among high school students is more frequent as compared with other age groups. Unlike the popular belief suggesting that slang is used by boys rather than girls, the findings suggested that young Iranians both male and female use slang as a badge of identity showing their attachment to the social group they wish to be identified with.

scholarly journals Visuospatial Reasoning and Its Relation to External Variables

2014 ◽  
Vol 24 (58) ◽  
pp. 197-204
Author(s):  
Juliana Carnevalli Siqueira Nery ◽  
Fabián Javier Marín Rueda
Keyword(s):  
Age Group ◽  
Older Students ◽  
Normative Sample ◽  
Male And Female ◽  
Visuospatial Reasoning ◽  
External Variables ◽  
Belo Horizonte ◽  
Performance Results ◽  
The City ◽  
Age And Sex

In this study, the relation of age and sex with visuospatial reasoning assessed by the Cube Test was investigated. In addition, a comparative study was conducted between this study sample and the normative group of the test with regard to visuospatial reasoning performance results. Six hundred and eighty-four students participated in this study, from the city of Belo Horizonte (State of Minas Gerais, Brazil), aged between 15 and 57 years old, both male and female. The results showed both age and sex differences, where younger students showed a significantly higher performance than older students and men showed significantly higher averages than women in every test comparison. In the study with the normative sample, men showed higher averages than women throughout every age group and in the overall result of both studies. The results obtained reflect those found in the literature and highlight the influence of age and sex on visuospatial reasoning.

scholarly journals Svalbard reindeer (Rangifer tarandus platyrhynchus) antler characteristics reflecting the local environmental conditions

2019 ◽  
Vol 46 (1) ◽  
pp. 16-23
Author(s):  
Jan Kavan ◽  
Veronika Anděrová
Keyword(s):  
Environmental Conditions ◽  
Rangifer Tarandus ◽  
Well Being ◽  
Climatic Conditions ◽  
High Mountain ◽  
Atmospheric Conditions ◽  
Individual Subject ◽  
Svalbard Reindeer ◽  
Invasive Method ◽  
Antler Size

AbstractA new non-invasive method based on picture analysis was used to estimate the conditions in Svalbard reindeer populations. The well-being of an individual subject is often expressed through visual indices. Two distinct reindeer populations were compared based on their antler parameters. Relative antler size and number of tines are variables supposed to reflect correspondingly the environmental conditions of sedentary populations within the growing season. The occurrence areas of two studied populations are distinctly isolated – separated with high mountain ridges, glaciers and fjords. The population in Petuniabukta occupies a sparsely vegetated region with harsh climatic conditions, whereas Skansbukta represents an area with continuous tundra vegetation cover, milder climatic conditions and, consequently, also a longer vegetation season. These environmental factors probably caused significant differences in the relative antler size and number of tines in the studied species. The Skansbukta population exhibited a larger relative antler size and higher number of tines than the population in Petuniabukta (both parameters differed significantly, p < 0.01). This difference reflects concisely the different environmental conditions of both locations. A comparison of Skansbukta population antler characteristics between years 2017 and 2018 did not reveal significant changes, most probably due to very similar atmospheric conditions in these two years (in terms of air temperature).

The age distribution in the Taimyr population wild northern deer (Rangifer Tarandus) in the first decades of 21 centuries

2021 ◽  
pp. 15-21
Author(s):  
A. Shapkin ◽  
R. Ivanova ◽  
N. Arsentseva ◽  
N. Sukhanova
Keyword(s):  
Age Structure ◽  
Rangifer Tarandus ◽  
Age Distribution ◽  
Age Groups ◽  
Base Material ◽  
Middle Level ◽  
Reproduction Rate ◽  
Male And Female ◽  
Field Samples ◽  
Wild Deer

Objective: mathematical demography means to identify and evaluate the age distribution of male and female of Taimyr tundra reindeer in the first decade of the XXI century and future trends in demographic situation Taimyr population.Materials and methods. The base material for evaluating the current state of the population age structure Taimyr steel fishing representative sample of male and female wild deer (n = 10845 individuals) collected in the West, Central and Taimyr Putorana in 2001-2008., And the deer samples (n = 1569 individuals), the floor of which is unknown. Determination of individual animals from age and older (n = 9773 individuals) performed on histological sections of cutters according to the corresponding procedure. To repay the random deviations of sample data because of a lack of presence of immature animals (calves, yearlings, young 1-2 years) (selectivity of fishing is directed primarily at the production of individuals older than 3 years, why animals in different age groups in the samples is greater than there are in the population) applies a smoothing procedure. Then, positive deviation of the number of individuals in the same age group were leveled due to negative deviations in adjacent groups.Results. By smoothed age ranges of the field samples from 2001-2008 the current age distribution of Taimyr wild reindeer calculated and analyzed. The study showed that the theoretical current age distribution of males with realized breeding is 77.03, females - 80.56, in the combined groups of animals - 82.35%. The real population has 18-19 age generations of males and females. The reproductive core of males from 3 to 10 years old is 48.43%, individuals of age limit 11 years and older occupy 1.96% of this sex and age structure, calves and young animals for 1-2 years - 24.64%. For the reproductive part of females aged 3–15 years, the overall age distribution is 55.34%, and the proportion of juveniles and young animals, according to calculations, is determined in this part of the population at 25.16%. In the combined current age distribution, males, females: calves and young animals accounted for 27.72%, the sexually mature part with animals of older and age-specific ages - 54.63%.Conclusion. Demographic Taimir population modeling operation in the first decade of the XXI century long materials commercial samples collected at commercial points shown at current age distribution of the realized and reproduction conditions for existing commercial load males - 77.03 for females - 80.56 and for unified groups (males, females) - 82.4%. Meanwhile, the steady state and stable age distribution Taimyr tundra wild deer can reach a middle-level only when the fecundity of female reproductive generations with clean reproduction rate (R0) equal in population groupings 1.0

Status Signaling Is Absent within Age-and-Sex Classes of Harris' Sparrows

The Auk ◽  
1988 ◽  
Vol 105 (3) ◽  
pp. 424-49 ◽  
Author(s):  
Wendy M. Jackson ◽  
Sievert Rohwer ◽  
Robin L. Winnegrad
Keyword(s):  
Social Status ◽  
Adult Males ◽  
Fighting Ability ◽  
Status Signaling ◽  
Adult Females ◽  
The Status ◽  
Signaling Hypothesis ◽  
Mixed Age ◽  
Badge Size ◽  
Age And Sex

Abstract We tested the status-signaling hypothesis in two groups of same-age and same-sex Harris' Sparrows (Zonotrichia querula). Unlike flocks of mixed age and sex composition, badge size did not correlate with social status in these groups; thus, status signaling does not appear to occur within age-and-sex classes of Harris' Sparrows. Other predictions of the status-signaling hypothesis we tested were that (1) fighting ability and social status should be correlated, and (2) fighting ability and badge size should be correlated. We used a multivariate assessment of body size as an indicator of fighting ability and found no support for either prediction in the flock of adult females. In the flock of adult males, large birds were more dominant (Prediction 1) but fighting ability and badge size were not correlated (contra Prediction 2).

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