Sexual dimorphism in body composition of small mammals

2001 ◽  
Vol 79 (6) ◽  
pp. 1016-1020 ◽  
Author(s):  
A I Schulte-Hostedde ◽  
J S Millar ◽  
G J Hickling
Keyword(s):  
Body Composition ◽  
Body Size ◽  
Sexual Dimorphism ◽  
Muscle Mass ◽  
Small Mammals ◽  
Mate Guarding ◽  
Dry Mass ◽  
Deer Mice ◽  
Neotoma Cinerea ◽  
Fat Stores

Differences in reproductive roles between the sexes may lead to sexual dimorphism in body composition. Body size and composition of three species of small mammals (bushy-tailed wood rats (Neotoma cinerea Ord), deer mice (Peromyscus maniculatus Wagner), and red-backed voles (Clethrionomys gapperi Vigors)) were analyzed to test the predictions that (i) males will have more muscle mass than females and (ii) females will have more fat than males. Results supported the first prediction but not the second. For all three species, males had more lean dry mass relative to body size than females, but females did not have relatively more fat than males. Muscle mass of males may aid in mate-searching and mate-guarding activities, but fat content may not differ between the sexes because female small mammals depend on increased ingestion rates, rather than fat stores, to support reproduction.

Evaluating body condition in small mammals

2001 ◽  
Vol 79 (6) ◽  
pp. 1021-1029 ◽  
Author(s):  
A I Schulte-Hostedde ◽  
J S Millar ◽  
G J Hickling
Keyword(s):  
Body Condition ◽  
Small Mammals ◽  
Isotope Dilution ◽  
Condition Index ◽  
Dry Mass ◽  
Fat Content ◽  
Body Water ◽  
Deer Mice ◽  
Fitness Consequences ◽  
Neotoma Cinerea

Body condition (energy reserves) can have important fitness consequences. Measuring condition of live animals is typically done by regressing body mass on measures of body size and using the residuals as an index of condition. The validity of this condition index was evaluated by determining whether it reflected measured fat content of five species of small mammals (yellow-pine chipmunks (Tamias amoenus Allen), bushy-tailed wood rats (Neotoma cinerea Ord), deer mice (Peromyscus maniculatus Ord), red-backed voles (Clethrionomys gapperi Vigors), and meadow voles (Microtus pennsylvanicus Ord)). We also determined whether body water could predict fat content, enabling the use of hydrogen-isotope dilution for estimating condition. For all five species, condition estimates weakly predicted fat content and more accurately predicted variation in lean dry mass and water content. The relationship between body water and fat content was inconsistent among the five species, discouraging against the general use of isotope dilution in these animals. Although ecologically important, these indices are best interpreted as explaining variation in all constituents of body composition.

Intraspecific variation in testis size of small mammals: implications for muscle mass

2003 ◽  
Vol 81 (4) ◽  
pp. 591-595 ◽  
Author(s):  
Albrecht I Schulte-Hostedde ◽  
John S Millar ◽  
Graham J Hickling
Keyword(s):  
Muscle Mass ◽  
Intraspecific Variation ◽  
Small Mammals ◽  
Deer Mouse ◽  
Dry Mass ◽  
Relative Increase ◽  
Testis Size ◽  
Individual Fitness ◽  
Neotoma Cinerea ◽  
Male Mate

Intraspecific variation in testis size is usually interpreted in the context of sperm competition, yet an unconsidered consequence of increased testis size may be an increase in the production of testosterone, which can affect the growth of muscle mass. After muscle mass is corrected for body size, male small mammals have more muscle mass than females, which suggests that it may be a sexually selected trait. An enhanced musculature may have fitness consequences with respect to male mate-searching activities and male–male competition for access to females. We tested the prediction that males with large testes have more muscle mass (measured as lean dry mass) by examining testis size and body composition in three species of small mammals (bushy-tailed wood rat (Neotoma cinerea), deer mouse (Peromyscus maniculatus), and red-backed vole (Clethrionomys gapperi)) from the Kananaskis Valley, Alberta. In all three species, males with relatively large testes had relatively more lean dry mass than males with relatively small testes. This suggests that a secondary consequence of relatively large testes may be a relative increase in muscle mass. Further research should investigate alternative effects of intraspecific variation in testis size on individual fitness within wild populations to gain further insight into sexual selection.

Sexual dimorphism in thick-billed murres, Uria lomvia

1993 ◽  
Vol 71 (2) ◽  
pp. 346-351 ◽  
Author(s):  
Donald T. Stewart
Keyword(s):  
Sexual Selection ◽  
Body Size ◽  
Sexual Dimorphism ◽  
Discriminant Analysis ◽  
Driving Force ◽  
Mate Guarding ◽  
Canonical Discriminant Analysis ◽  
Uria Lomvia ◽  
Breeding Sites ◽  
Univariate Statistics

The pattern of sexual dimorphism in thick-billed murres, Uria lomvia, from the Lancaster Sound – Jones Sound region, Northwest Territories, was examined for weight and 21 skeletal characters. Univariate statistics (Bonferroni-corrected t-tests) indicated that males were significantly larger than females in 6 bill and skull characters. Multivariate statistics also indicated that males had larger bills and skulls than females (based on canonical discriminant analysis), but males were not larger than females in overall body size (as defined by the first principal-components axis). The direction and magnitude of dimorphism were consistent with a hypothesis based on sexual selection as the driving force. In particular, large bill and skull sizes in males are consistent with agonistic behaviours associated with male–male competition for breeding sites and mate guarding.

scholarly journals Relative abundance of the Prairie Long-tailed Weasel (Mustela frenata longicauda) in southwestern Alberta

2013 ◽  
Vol 127 (2) ◽  
pp. 131
Author(s):  
Garry E. Hornbeck ◽  
Dan Soprovich
Keyword(s):  
Body Size ◽  
Small Mammals ◽  
Relative Abundance ◽  
Small Mammal ◽  
Peromyscus Maniculatus ◽  
Capture Probability ◽  
Deer Mice ◽  
Microtus Spp ◽  
Capture Rates

Prairie Long-tailed Weasels (Mustela frenata longicauda) were live-trapped during fall 2005, 2006, and 2007 at Pine Coulee Reservoir and during fall 2005, 2008, and 2010 at Twin Valley Reservoir in southwestern Alberta. Our objective was to estimate the relative abundance of the Long-tailed Weasel and to estimate the relative abundance of small mammal prey. Body size and capture rates are reported for Long-tailed Weasels, and we report capture rates of small mammals. Annual capture rates for Long-tailed Weasels at Pine Coulee Reservoir were 0.44, 0.41, and 0.50 individuals per 100 corrected trap-nights (0.42, 0.38, and 0.48 individuals/100 trap-nights) in 2005, 2006, and 2007, respectively. No Long-tailed Weasels were captured at Twin Valley Reservoir. The probability of capturing zero Long-tailed Weasels at Twin Valley Reservoir was very low, assuming a true capture probability equivalent to that observed at Pine Coulee Reservoir. Deer Mice (Peromyscus maniculatus) were the most abundant small mammals captured in both project areas. Few shrews (Sorex spp.) and voles (Microtus spp.) were captured in either area.

Sexual dimorphism and evidence for intrasexual selection from quill impalements, injuries, and mate guarding in porcupines (Erethizon dorsatum)

1997 ◽  
Vol 75 (6) ◽  
pp. 847-854 ◽  
Author(s):  
Richard Alan Sweitzer ◽  
Joel Berger
Keyword(s):  
Sexual Selection ◽  
Body Size ◽  
Sexual Dimorphism ◽  
Mate Guarding ◽  
Reproductive Activity ◽  
Erethizon Dorsatum ◽  
Threshold Size ◽  
Guarding Behavior ◽  
Mating Opportunities ◽  
Foot Pad

Sexual selection is a commonly cited explanation for sexual size dimorphism. We examined patterns of sexual dimorphism in North American porcupines (Erethizon dorsatum) and used data on quill impalements, injuries, and guarding behavior to examine the intrasexual component of sexual selection among male porcupines. Results indicated that porcupines were sexually dimorphic for foot-pad length, body length, and body mass because males grew more rapidly and for longer periods than females. Quill impalements, injuries, and guarding episodes were restricted predominantly to older, larger males, intimating that only the largest porcupines were reproductively active. Regression analyses suggested that size was more important than age in predicting reproductive activity among males. Also, relatively few quill impalements and guarding episodes among younger, smaller animals suggest that there is a threshold size below which male porcupines do not attempt to compete for mate access. Although our data do not directly link larger body size in males with relatively high reproductive success, they suggest that sexual dimorphism in this species is at least partly the result of the intrasexual component of sexual selection. It is also possible that females select males on the basis of quill morphology or some other indicator of male quality. Thus, our understanding of sexual dimorphism in porcupines would benefit from additional research investigating the extent to which body size and patterns of quill number or size are advantageous to male porcupines in garnering mating opportunities and enhancing fitness.

Effect of Body Size and Body Composition on Survival in Peritoneal Dialysis Patients

2005 ◽  
Vol 25 (5) ◽  
pp. 461-469 ◽  
Author(s):  
Nirupama Ramkumar ◽  
Lisa M. Pappas ◽  
Srinivasan Beddhu
Keyword(s):  
Body Composition ◽  
Peritoneal Dialysis ◽  
Body Size ◽  
Muscle Mass ◽  
High Body Mass Index ◽  
Survival Models ◽  
Urinary Creatinine ◽  
Parametric Survival ◽  
Lower Hazard ◽  
High Bmi

Background Using 24-hour urinary creatinine excretion as a measure of muscle mass, we examined whether body composition influences the survival of incident peritoneal dialysis (PD) patients. We hypothesized that patients with high body mass index (BMI) and low muscle mass might be considered to have high levels of body fat. Methods Using serum creatinines and creatinine clearances reported on Medical Evidence Form 2728, 24-hour urinary creatinine was calculated in 10140 incident PD patients with normal (18.5 – 24.9 kg/m2) or high (≥25 kg/m2) BMI. Patients were classified as low and normal/high muscle mass groups based on the 25th percentile of 24-hour urinary creatinine (0.64 g/day). Results In multivariable parametric survival models, compared to the normal BMI–normal/high muscle mass patients, high BMI–normal/high muscle mass patients had lower hazard of all-cause [hazard ratio (HR) 0.90, 95% confidence interval (CI) 0.83 – 0.97] and cardiovascular (HR 0.88, 95% CI 0.79 – 0.97) death; high BMI patients with low muscle mass had higher hazard of all-cause (HR 1.29, 95% CI 1.17 – 1.42) and cardiovascular (HR 1.21, 95% CI 1.06 – 1.39) death. Conclusion Both body size and body composition influence survival of incident PD patients. As incident PD patients with high BMI and normal or high muscle mass have the best survival, PD patients should be encouraged to gain muscle mass rather than fat mass.

Sexual dimorphism and testosterone responsiveness in hypaxial muscles of the northern leopard frog, Rana pipiens

1998 ◽  
Vol 19 (3) ◽  
pp. 269-279 ◽  
Author(s):  
Daniel G. Blackburn ◽  
Vincent A. Bernardo
Keyword(s):  
Sexual Dimorphism ◽  
Protein Content ◽  
Muscle Mass ◽  
Rana Pipiens ◽  
Dry Mass ◽  
Rectus Abdominis ◽  
Leopard Frog ◽  
Northern Leopard Frog ◽  
Androgen Treatment

AbstractAbdominal hypaxial muscles of male anurans function in vocalization by causing forcible expulsion of pulmonary air through the larynx. The hypaxial muscles were studied in the leopard frog, Rana pipiens, to test whether functions of these muscles in males are reflected in sexual dimorphism and in androgen responsiveness. The combined abdominal oblique muscles and the rectus abdominis showed significant sexual dimorphism in wet mass and dry mass. However, the abdominal oblique muscles were less concentrated in protein content in males than in females. In overwintering males, exogenous testosterone cypionate stimulated a significant increase in mass and protein content of the abdominal oblique and rectus abdominis muscles. Castration had no effect on muscle mass or on the response to androgen treatment.

scholarly journals Food insecurity, diet quality and body composition: data from the Healthy Life Trajectories Initiative (HeLTI) pilot survey in urban Soweto, South Africa

2021 ◽  
pp. 1-9
Author(s):  
Sarah H Kehoe ◽  
Stephanie V Wrottesley ◽  
Lisa Ware ◽  
Alessandra Prioreschi ◽  
Catherine Draper ◽  
...  
Keyword(s):  
South Africa ◽  
Body Composition ◽  
Food Security ◽  
Body Size ◽  
Food Insecurity ◽  
Diet Quality ◽  
Urban Poor ◽  
Reproductive Age ◽  
Healthy Life ◽  
Life Trajectories

Abstract Objective: To determine whether food security, diet diversity and diet quality are associated with anthropometric measurements and body composition among women of reproductive age. The association between food security and anaemia prevalence was also tested. Design: Secondary analysis of cross-sectional data from the Healthy Life Trajectories Initiative (HeLTI) study. Food security and dietary data were collected by an interviewer-administered questionnaire. Hb levels were measured using a HemoCue, and anaemia was classified as an altitude-adjusted haemoglobin level < 12·5 g/dl. Body size and composition were assessed using anthropometry and dual-energy x-ray absorptiometry. Setting: The urban township of Soweto, Johannesburg, South Africa. Participants: Non-pregnant women aged 18–25 years (n 1534). Results: Almost half of the women were overweight or obese (44 %), and 9 % were underweight. Almost a third of women were anaemic (30 %). The prevalence rates of anaemia and food insecurity were similar across BMI categories. Food insecure women had the least diverse diets, and food security was negatively associated with diet quality (food security category v. diet quality score: B = –0·35, 95 % CI –0·70, –0·01, P = 0·049). Significant univariate associations were observed between food security and total lean mass. However, there were no associations between food security and body size or composition variables in multivariate models. Conclusions: Our data indicate that food security is an important determinant of diet quality in this urban-poor, highly transitioned setting. Interventions to improve maternal and child nutrition should recognise both food security and the food environment as critical elements within their developmental phases.

scholarly journals The Diagnostic-Measurement Method—Resting Energy Expenditure Assessment of Polish Children Practicing Football

Diagnostics ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 340
Author(s):  
Edyta Łuszczki ◽  
Anna Bartosiewicz ◽  
Katarzyna Dereń ◽  
Maciej Kuchciak ◽  
Łukasz Oleksy ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Body Composition ◽  
Energy Expenditure ◽  
Muscle Mass ◽  
Indirect Calorimetry ◽  
Energy Demand ◽  
Body Height ◽  
Resting Energy Expenditure ◽  
Blood Pressure Monitor ◽  
Resting Energy

Establishing the amount of energy needed to cover the energy demand of children doing sport training and thus ensuring they achieve an even energy balance requires the resting energy expenditure (REE) to be estimated. One of the methods that measures REE is the indirect calorimetry method, which may be influenced by many factors, including body composition, gender, age, height or blood pressure. The aim of the study was to assess the correlation between the resting energy expenditure of children regularly playing football and selected factors that influence the REE in this group. The study was conducted among 219 children aged 9 to 17 using a calorimeter, a device used to assess body composition by the electrical bioimpedance method by means of segment analyzer and a blood pressure monitor. The results of REE obtained by indirect calorimetry were compared with the results calculated using the ready-to-use formula, the Harris Benedict formula. The results showed a significant correlation of girls’ resting energy expenditure with muscle mass and body height, while boys’ resting energy expenditure was correlated with muscle mass and body water content. The value of the REE was significantly higher (p ≤ 0.001) than the value of the basal metabolic rate calculated by means of Harris Benedict formula. The obtained results can be a worthwhile suggestion for specialists dealing with energy demand planning in children, especially among those who are physically active to achieve optimal sporting successes ensuring proper functioning of their body.

scholarly journals AB0267 BODY COMPOSITION IN PATIENTS WITH RHEUMATOID ARTHRITIS

2020 ◽  
Vol 79 (Suppl 1) ◽  
pp. 1432.2-1432
Author(s):  
N. Toroptsova ◽  
O. Dobrovolskaya ◽  
N. Demin ◽  
L. Shornikova
Keyword(s):  
Rheumatoid Arthritis ◽  
Body Composition ◽  
Muscle Mass ◽  
Dual Energy ◽  
X Ray ◽  
T Score ◽  
Osteosarcopenic Obesity ◽  
The Mean ◽  
Total Fat ◽  
Appendicular Muscle Mass

Background:Rheumatoid arthritis (RA) is a complex inflammatory disease that modifies body composition. Using the dual-energy x-ray absorptiometry (DXA) in RA patients could be a method for body composition changes detection.Objectives:To study the body composition using DXA in patients with RA.Methods:The study involved 79 women with RA, median age 60 [55; 65] years. The bone mineral density (BMD) was measured by dual-energy x-ray absorptiometry using «Discovery A» (Hologic, USA). Assessment of body composition was carried out, using the program «Whole body». Sarcopenia (SP) was diagnosed as a decrease in appendicular mass index (AMI) <6.0 kg/m2. Osteoporosis (OP) was diagnosed as a decrease in T-score <-2.5 SD. Osteosarcopenia was determined when T-score was <-1.0 SD, AMI was <6.0 kg/m2, osteosarcopenic obesity - T-score was <-1.0 SD, AMI was <6.0 kg/m2and total fat was >35%.Results:The mean duration of RA was 9 [3; 11] years. The mean body mass index (BMI) was 27.6±4.8 kg/m2. Disease activity score in 28 joints-erythrocyte sedimentation rate was 4.5±1.3 points for the group. 39 (49.3%) patients used oral glucocorticoids continuously. Appendicular muscle mass and AMI were on average 17.8±3.0 kg and 6.8±1.0 kg/m2, respectively. AMI <6 kg/m2was detected in 20 (25.3%) patients. 56 (70.9%) women with RA had total fat > 35%, while only 22 (27.8%) of women with RA had obesity according to BMI (BMI >30 kg/m2). Isolated OP was found in 13 (16.5%), osteosarcopenia in 7 (8.9%) and osteosarcopenic obesity in 13 (16.5%) patients RA. No cases with isolated sarcopenia or sarcopenic obesity were detected. Only 3 (3.8%) patients did not have appendicular muscle mass, AMI and BMD decrease and overfat or obesity.Conclusion:About 97% women with RA had abnormal body composition phenotype: 16,5% - OP, 8.9% -osteosarcopenia, 16,5% - osteosarcopenic obesity and 54,4% - overfat.Disclosure of Interests:None declared

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