scholarly journals The relationship between the fat content of Svalbard reindeer in autumn and their death from starvation in winter

Rangifer ◽  
1986 ◽  
Vol 6 (2) ◽  
pp. 311 ◽  
Author(s):  
N. J.C. Tyler

The relationship between body fat reserves in autumn and age-specific mortality in winter were examined in Svalbard reindeer (Rangifer tarandus platyrhynchus Vrolik). Total dissectible fat (TDF) was measured in 17 females, 1-12 years of age, shot on Spitsbergen (78°N lat.) in autumn 1980-1981. TDF declined with age in reindeer 2 years and older. The youngest females which died in winter, with the exception of calves, were aged 7 years old. A direct causal link between low autumn TDF and mortality in winter seemed unlikely. Mortality was clearly associated with the degree of wear of molariform teeth. Perhaps severe tooth wear results in inefficient mastication of low quality forage and a decline in the rate of passage of digesta, thereby restricting the amount of food that reindeer can eat. A simple model of the energy balance of female Svalbard reindeer in winter shows that they must obtaine not less than about 74% of their total energy requirements from forage. Consequently, differences in the ability of individual reindeer to feed in winter are potentially more important for survival than differences in their fat content in autumn.

Rangifer ◽  
1987 ◽  
Vol 7 (1) ◽  
pp. 29 ◽  
Author(s):  
Nicholas Tyler

Svalbard reindeer (Rangifer tarandus platyrhynchus) store large reserves of subcutaneous fat during summer and autumn which, it has been suggested, might be sufficient to meet a substantial part of their energy requirements during winter. An alternative suggestion, however, is that fat is not their main source of energy after all and, moreover, that the principal role of their fat reserves is for enhancing reproductive success rather than for substituting for forage (Tyler, in press). Is it realistic to suggest that these high arctic herbivores could meet the greater part of their energy requirements in winter by feeding, given that the aerial biomass of available forage in Svalbard in late winter is very low? This question was investigated by using a simple model to predict what rate of food intake Svalbard reindeer would have to achieve to maintain energy balance in late winter. The results were surprisingly low: pregnant and nonpregnant females could mett their daily energy demands by consuming 3.1 and 1.7 g dry matter per grazing minute, respectively. This supports the suggestion that Svalbard reindeer could live principally off forage in winter.


2021 ◽  
Vol 376 (1831) ◽  
pp. 20200215 ◽  
Author(s):  
L. Monica Trondrud ◽  
Gabriel Pigeon ◽  
Steve Albon ◽  
Walter Arnold ◽  
Alina L. Evans ◽  
...  

Seasonal energetic challenges may constrain an animal's ability to respond to changing individual and environmental conditions. Here, we investigated variation in heart rate, a well-established proxy for metabolic rate, in Svalbard reindeer ( Rangifer tarandus platyrhynchus ), a species with strong seasonal changes in foraging and metabolic activity. In 19 adult females, we recorded heart rate, subcutaneous temperature and activity using biologgers. Mean heart rate more than doubled from winter to summer. Typical drivers of energy expenditure, such as reproduction and activity, explained a relatively limited amount of variation (2–6% in winter and 16–24% in summer) compared to seasonality, which explained 75% of annual variation in heart rate. The relationship between heart rate and subcutaneous temperature depended on individual state via body mass, age and reproductive status, and the results suggested that peripheral heterothermy is an important pathway of energy management in both winter and summer. While the seasonal plasticity in energetics makes Svalbard reindeer well-adapted to their highly seasonal environment, intraseasonal constraints on modulation of their heart rate may limit their ability to respond to severe environmental change. This study emphasizes the importance of encompassing individual state and seasonal context when studying energetics in free-living animals. This article is part of the theme issue ‘Measuring physiology in free-living animals (Part II)’.


1994 ◽  
Vol 24 (3) ◽  
pp. 122-130 ◽  
Author(s):  
Lynne Widrich ◽  
Karen Ortlepp

The present study examined the relationship between work stress and a specific aspect of marital functioning, namely, marital interaction. An interactionist model of stress was adopted, with three role stresses, namely, role ambiguity, role conflict and role overload, being used as indicators of work stress. Despite the abundance of studies investigating the link between employment and family functioning over the past decade, the causal link between the two domains remains unclear. As previous research has indicated that the relationship between work and family is neither simple nor linear, the present study aimed to investigate the role of job satisfaction in the relationship. The final sample of the study consisted of 80 married men employed in a large financial organization. Data were gathered in the form of self-report questionnaires. Statistical analysis, using a longitudinal path analytic research design, did not support the proposed mediational model, that is, job satisfaction was not found to mediate the relationship between work stress and marital functioning.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Norie Saito ◽  
Masato Furuhashi ◽  
Masayuki Koyama ◽  
Yukimura Higashiura ◽  
Hiroshi Akasaka ◽  
...  

AbstractFatty acid-binding protein 4 (FABP4) is secreted from adipose tissue and acts as an adipokine, and an elevated circulating FABP4 level is associated with metabolic disorders and atherosclerosis. However, little is known about the causal link between circulating FABP4 level and mortality in a general population. We investigated the relationship between FABP4 concentration and mortality including cardiovascular death during a 12-year period in subjects of the Tanno-Sobetsu Study, a population-based cohort (n = 721, male/female: 302/419). FABP4 concentration at baseline was significantly higher in female subjects than in male subjects. All-cause death occurred in 123 (male/female: 74/49) subjects, and 34 (male/female: 20/14) and 42 (male/female: 26/16) subjects died of cardiovascular events and cancer, respectively. When divided into 3 groups according to tertiles of FABP4 level at baseline by sex (T1–T3), Kaplan–Meier survival curves showed that there were significant differences in rates of all-cause death and cardiovascular death, but not cancer death, among the groups. Multivariable Cox proportional hazard model analysis with a restricted cubic spline showed that hazard ratio (HR) for cardiovascular death, but not that for all-cause death, significantly increased with a higher FABP4 level at baseline after adjustment of age and sex. The risk of cardiovascular death after adjustment of age, sex, body mass index and levels of brain natriuretic peptide and high-sensitivity C-reactive protein in the 3rd tertile (T3) group (HR: 4.96, 95% confidence interval: 1.20–22.3) was significantly higher than that in the 1st tertile (T1) group as the reference. In conclusion, elevated circulating FABP4 concentration predicts cardiovascular death in a general population.


1998 ◽  
Vol 83 (3) ◽  
pp. 931-934
Author(s):  
Niels Moller ◽  
Peter O’Brien ◽  
K. Sreekumaran Nair
Keyword(s):  

2011 ◽  
Vol 321 ◽  
pp. 192-195
Author(s):  
Qing Bin Yang ◽  
Xiao Yang

In order to analysis the relationship between the strength and elongation and the blended ratio of SPF/Cotton blended yarn, the strength and elongation of SPF /cotton blended yarn with different blended ratio were measured and compared with the simple model. The results indicated that For the SPF/cotton blended yarn, the difference between the experimental data and the model value is remarkable because of the high cohesion of the cotton fibers.


2019 ◽  
Vol 46 (1) ◽  
pp. 16-23
Author(s):  
Jan Kavan ◽  
Veronika Anděrová

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).


Rangifer ◽  
2005 ◽  
Vol 25 (2) ◽  
pp. 85-96 ◽  
Author(s):  
Sabine Sampels ◽  
Jana Pickova ◽  
Eva Wiklund

Carcass composition in reindeer is affected by feed intake and the age and sex of the animal. Studies have also shown that age, sex, carcass trim fat content and total intramuscular fat content (IMF) influence lipid class composition. The aim of this study was to compare lipid class composition and IMF in relation to carcass weight, conformation and trim fat content, and to investigate how these parameters are affected by age, sex and different feed sources. Five groups of reindeer were studied. Two groups of calves were fed two grain-based pelleted feeds with different lipid compositions for approximately two months before slaughter. One of these groups was fed with conventional pellets, and the other with pellets enriched with linseed cake to increase the amount of n-3 fatty acids in the diet. Three groups of grazing reindeer were also included in the study, consisting of adult males, adult females or calves. Reindeer calves fed pellets had higher slaughter weights, higher trim fat content and better carcass conformation scores compared to the grazing calves. However, there was no significant difference in IMF between pellet-fed and grazing calves. Adult female reindeer had the highest and grazing calves the lowest slaughter weights, trim fat and IMF. There was no difference in lipid class composition in meat from calves fed with the two pelleted feeds, whereas grazing calves had a higher amount of phospholipids. Squalene was identified and quantified as a component of intramuscular lipids in reindeer meat. Effekt av produktionssystem, ålder och kön på slaktkroppskvalitet och några biokemiska egenskaper hos renköttAbstract in Swedish / Sammandrag: Slaktkroppssammansättningen hos renar påverkas av både foderintag, fodersammansättning och djurens ålder och kön. Tidigare har vi visat att renens kön, ålder, mängden intramuskulärt fett (IMF) och putsfett på slaktkroppen påverkar sammansättningen av lipidklasser. Syftet med denna studie var att jämföra lipidklassammansättningen och IMF i relation till slaktkroppens vikt, form och mängden putsfett och att undersöka hur dessa parametrar påverkas av renarnas kön, ålder och olika typer av foder (bete och pellets). Fem grupper renar ingick i studien (totalt 38 djur). Två grupper kalvar utfodrades med två sorters pellets med olika fettsammansättning under två månader före slakt. Den ena gruppen fick normala pellets (CPD) (Renfor Bas) medan den andra gruppen fick pellets som hade en tillsats av linfrökaka (LPD) för att öka mängden n-3 fettsyror i fodret. Dessutom ingick tre grupper betesdjur i studien: vajor, sarvar och kalvar. Utfodring med pellets gav slaktkroppar med bättre klassning, högre slaktvikter och mer putsfett jämfört med slaktkroppar från betande kalvar. Vajorna hade de högsta och betande kalvar de lägsta slaktvikterna, minst putsfett och lägst halt av IMF. Utfodringen med pellets gav ingen signifikant skillnad i IMF mellan betande och utfodrade renkalvar. Vi fann ingen skillnad i lipidklassammansättning mellan de två utfodrade kalvgrupperna, men köttet från de betande kalvarna hade en högre halt av fosfolipider. Vi kunde också identifiera och kvantifiera squalen som en komponent i intramuskulärt fett i renkött.


Author(s):  
Honoré Samuel NTAVOUA

<p>The nature of the link between economic growth, public and private consumption in theoretical and empirical research is not well known in Cameroon. The objective of this study is to examine the nature of the relationship between economic growth, public and private consumption in Cameroon from 1980 to 2015. In order to achieve our goal, the data from the CENUCED were collected and tested in the autoregressive vector model (VAR). The delay selection statistic for VAR allowed us to have the following causality results: in Cameroon, there is a unidirectional relationship between economic growth towards public consumption and economic growth towards private consumption. Meanwhile, there is no causal link between public and private consumption, from public and private consumption to economic growth. Thus, the recommendation is that the Cameroonian government should create an incentive framework conducive to the improvement of public and private consumption to stimulate investment and economic growth.</p>


Sign in / Sign up

Export Citation Format

Share Document