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1.
PLoS One ; 14(5): e0216223, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31071155

RESUMO

Satellite telemetry is an increasingly utilized technology in wildlife research, and current devices can track individual animal movements at unprecedented spatial and temporal resolutions. However, as we enter the golden age of satellite telemetry, we need an in-depth understanding of the main technological, species-specific and environmental factors that determine the success and failure of satellite tracking devices across species and habitats. Here, we assess the relative influence of such factors on the ability of satellite telemetry units to provide the expected amount and quality of data by analyzing data from over 3,000 devices deployed on 62 terrestrial species in 167 projects worldwide. We evaluate the success rate in obtaining GPS fixes as well as in transferring these fixes to the user and we evaluate failure rates. Average fix success and data transfer rates were high and were generally better predicted by species and unit characteristics, while environmental characteristics influenced the variability of performance. However, 48% of the unit deployments ended prematurely, half of them due to technical failure. Nonetheless, this study shows that the performance of satellite telemetry applications has shown improvements over time, and based on our findings, we provide further recommendations for both users and manufacturers.


Assuntos
Animais Selvagens/fisiologia , Ecossistema , Monitoramento Ambiental , Sistemas de Informação Geográfica , Astronave , Telemetria , Animais
2.
J Anim Breed Genet ; 134(2): 144-151, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27488613

RESUMO

The aim of this study was to evaluate the quality of the data provided from sheepdog trials in Norway, estimate heritabilities, repeatabilities and genetic correlations for the traits included in the trial and make recommendations on how sheepdog trials best can be utilized in the breeding of Border Collies in Norway. The analyses were based on test results from sheepdog trials carried out in Norway from 1993 to 2012. A total of 45 732 records from 3841 Border Collies were available, but after quality assurance only a third was left. The results demonstrated little information in the data. Heritabilities varied between 0.010 and 0.056 with standard errors ranging from 0.010 to 0.023, while repeatabilities ranged from 0.041 to 0.286. There is a need to assure the quality of data to improve the information in the test results. We recommend adding new traits based on the Herding Trait Characterization scheme evaluated in Sweden, and on traits from the predatory motor pattern, regarded as common for all dogs. These new traits may be scored across the elements that make up the current trial system, which should be kept in place to stimulate participation in the genetic evaluation scheme.


Assuntos
Cruzamento , Cães/genética , Cães/fisiologia , Animais , Cães/classificação , Feminino , Masculino , Noruega , Linhagem , Comportamento Predatório , Suécia
3.
J Anim Sci ; 86(1): 33-9, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17911228

RESUMO

Genotype x environment interaction (G x E) effects on live weaning weights of lambs were studied by using the 2 breeds Norwegian White sheep (NWS; heavy, long-tailed) and Spel sheep (Spel; lighter, short-tailed) as genetic groups (G). A total of 37,338 NWS lambs and 30,075 Spel lambs born from 1989 to 1999 on 40 farms that kept both breeds together were included in the analyses. Environment was characterized by farm x year (E). In a mixed linear model framework, significance of the random G x E effect and breed-specific environmental variances were tested by using a log-likelihood approach. Directions and magnitudes of the effect were described through variance component estimates. An across-genotype environmental correlation was also used. There was a significant G x E effect on lamb BW; significant breed differences were found for variance of flock x year effects, indicating different phenotypic plasticities with changing flock x year environments, with the NWS being more sensitive to environmental change. Further, the breed-specific residual variance was greater for NWS, indicating that the effects of environmental variation were larger for the weaning weights of the NWS breed within flock and year. Further, the correlation between flock x year effects for the 2 breeds was significantly different from unity (0.82 +/- 0.02), indicating that the common environment is "perceived" differently in the 2 breeds. The best environment for one breed is not necessarily best for the other breed, and vice versa. Solutions of flock x year effects may be used to describe how environmental characteristics such as climate and topography affect the production of different genotypes, and for clustering of environments, thus facilitating improvement of breeding programs and management schemes for domestic and wild ungulate populations.


Assuntos
Peso Corporal/genética , Meio Ambiente , Ovinos/genética , Desmame , Criação de Animais Domésticos , Animais , Feminino , Genótipo , Masculino , Noruega , Fatores de Tempo
4.
Nature ; 410(6832): 1096-9, 2001 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-11323672

RESUMO

Large-scale climatic fluctuations, such as the North Atlantic Oscillation (NAO), have been shown to affect many ecological processes. Such effects have been typically assumed to be linear. Only one study has reported a nonlinear relation; however, that nonlinear relation was monotonic (that is, no reversal). Here we show that there is a strong nonlinear and non-monotonic (that is, reversed) effect of the NAO on body weight during the subsequent autumn for 23,838 individual wild red deer (Cervus elaphus) and 139,485 individual domestic sheep (Ovis aries) sampled over several decades on the west coast of Norway. These relationships are, at least in part, explained by comparable nonlinear and non-monotonic relations between the NAO and local climatic variables (temperature, precipitation and snow depth). The similar patterns observed for red deer and sheep, the latter of which live indoors during winter and so experience a stable energy supply in winter, suggest that the (winter) climatic variability (for which the index is a proxy) must influence the summer foraging conditions directly or indirectly.


Assuntos
Clima , Cervos , Ovinos , Animais , Animais Domésticos , Animais Selvagens , Peso Corporal , Comportamento Alimentar , Feminino , Masculino , Noruega , Estações do Ano
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