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1.
Eur J Nutr ; 62(8): 3383-3396, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37653070

RESUMO

PURPOSE: Introducing healthy and sustainable diets early in life can promote lifelong healthy dietary patterns with a low environmental impact. Therefore, we aimed to estimate the environmental and nutritional consequences of a dietary change for 2-year-old children in Norway towards healthier dietary patterns. METHODS: Environmental impacts of the current habitual diet among 2-year-olds (n = 1413) were estimated for six impact categories and compared with scenario diets based on the Norwegian food-based dietary guidelines (FBDG) and the EAT-Lancet Commission reference diet. Last, we evaluated the nutritional adequacy of the diets against the Norwegian nutrition recommendations for children aged 2-5 years. The current diet was assessed by an FFQ. RESULTS: Environmental impacts of the current habitual diet were up to two times higher than those of the scenario diets. Compared with the current diet, impacts from the FBDG scenario diet were reduced by 35% for water use and 18% for terrestrial acidification, whereas impacts from the EAT-Lancet scenario diet were reduced by 51% for water use, 57% for terrestrial acidification, 36% for global warming potential and 27% for freshwater eutrophication. Milk and dairy products were the main contributors to environmental impacts in both the current diet and the FBDG scenario diet. The scenario diets were nutritionally adequate and improved the dietary quality among Norwegian 2-year-olds. CONCLUSION: Compared to current diets among young children, more plant-based dietary patterns in line with national FBDG or the EAT-Lancet Commission reference diet can improve the nutritional adequacy of diets and simultaneously reduce environmental impacts.


Assuntos
Dieta , Avaliação Nutricional , Humanos , Pré-Escolar , Política Nutricional , Laticínios , Água
2.
Artigo em Inglês | MEDLINE | ID: mdl-32726948

RESUMO

Climate change in the Nordic countries is projected to lead to both wetter and warmer seasons. This, in combination with associated vegetation changes and increased animal migration, increases the potential incidence of tick-borne diseases (TBD) where already occurring, and emergence in new places. At the same time, vegetation and animal management influence tick habitat and transmission risks. In this paper, we review the literature on Ixodes ricinus, the primary vector for TBD. Current and projected distribution changes and associated disease transmission risks are related to climate constraints and climate change, and this risk is discussed in the specific context of reindeer management. Our results indicate that climatic limitations for vectors and hosts, and environmental and societal/institutional conditions will have a significant role in determining the spreading of climate-sensitive infections (CSIs) under a changing climate. Management emerges as an important regulatory "tool" for tick and/or risk for disease transfer. In particular, shrub encroachment, and pasture and animal management, are important. The results underscore the need to take a seasonal view of TBD risks, such as (1) grazing and migratory (host) animal presence, (2) tick (vector) activity, (3) climate and vegetation, and (4) land and animal management, which all have seasonal cycles that may or may not coincide with different consequences of climate change on CSI migration. We conclude that risk management must be coordinated across the regions, and with other land-use management plans related to climate mitigation or food production to understand and address the changes in CSI risks.


Assuntos
Ixodes , Doenças Transmitidas por Carrapatos , Animais , Mudança Climática , Ecossistema , Dinâmica Populacional , Risco , Países Escandinavos e Nórdicos , Doenças Transmitidas por Carrapatos/epidemiologia
3.
Ambio ; 46(6): 630-643, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28215020

RESUMO

Climate change is likely to be one of the most important factors affecting our future food security. To mitigate negative impacts, we will require our crops to be more genetically diverse. Such diversity is available in crop wild relatives (CWRs), the wild taxa relatively closely related to crops and from which diverse traits can be transferred to the crop. Conservation of such genetic resources resides within the nation where they are found; therefore, national-level conservation recommendations are fundamental to global food security. We investigate the potential impact of climate change on CWR richness in Norway. The consequences of a 1.5 and 3.0 °C temperature rise were studied for the years 2030, 2050, 2070, 2080 and then compared to the present climate. The results indicate a pattern of shifting CWR richness from the south to the north, with increases in taxa turnover and in the numbers of threatened taxa. Recommendations for in situ and ex situ conservation actions over the short and long term for the priority CWRs in Norway are presented. The methods and recommendations developed here can be applied within other nations and at regional and global levels to improve the effectiveness of conservation actions and help ensure global food security.


Assuntos
Mudança Climática , Conservação dos Recursos Naturais , Produtos Agrícolas , Agricultura , Abastecimento de Alimentos , Noruega
4.
J Biol Rhythms ; 31(5): 522-33, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27634928

RESUMO

Occurrence of 24-h rhythms in species apparently lacking functional molecular clockwork indicates that strong circadian mechanisms are not essential prerequisites of robust timing, and that rhythmical patterns may arise instead as passive responses to periodically changing environmental stimuli. Thus, in a new synthesis of grazing in a ruminant (MINDY), crepuscular peaks of activity emerge from interactions between internal and external stimuli that influence motivation to feed, and the influence of the light/dark cycle is mediated through the effect of low nocturnal levels of food intake on gastric function. Drawing on risk allocation theory, we hypothesized that the timing of behavior in ruminants is influenced by the independent effects of light on motivation to feed and perceived risk of predation. We predicted that the antithetical relationship between these 2 drivers would vary with photoperiod, resulting in a systematic shift in the phase of activity relative to the solar cycle across the year. This prediction was formalized in a model in which phase of activity emerges from a photoperiod-dependent trade-off between food and safety. We tested this model using data on the temporal pattern of activity in reindeer/caribou Rangifer tarandus free-living at natural mountain pasture in sub-Arctic Norway. The resulting nonlinear relationship between the phasing of crepuscular activity and photoperiod, consistent with the model, suggests a mechanism for behavioral timing that is independent of the core circadian system. We anticipate that such timing depends on integration of metabolic feedback from the digestive system and the activity of the glucocorticoid axis which modulates the behavioral responses of the animal to environmental hazard. The hypothalamus is the obvious neural substrate to achieve this integration.


Assuntos
Ritmo Circadiano , Metabolismo Energético , Fotoperíodo , Rena/fisiologia , Animais , Comportamento Animal/fisiologia , Meio Ambiente , Feminino , Hipotálamo/fisiologia , Luz , Atividade Motora/fisiologia , Noruega , Comportamento Predatório
5.
J Pineal Res ; 43(3): 289-93, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17803527

RESUMO

In reindeer Rangifer tarandus, a high latitude species, the rhythmic production of melatonin periodically dissipates under natural photoperiods when, in mid-winter, there is near permanent darkness and again, in summer, when there is permanent light. In spring and autumn, as expected, melatonin production reflects the ambient light:dark (LD) cycle. We investigated the expression of circadian mechanisms on blood levels of melatonin in reindeer. Two experiments were conducted in which animals were transferred from natural photic conditions into continuous darkness for 3 days: (i) in February, when they had been exposed to an LD cycle (11L:13D) and (ii) in July, when they had been exposed to permanent light. In July, plasma levels of melatonin rose abruptly on exposure to darkness but then declined over 24 hr before displaying a second rise and decline over the following 36 hr. In contrast, in February, levels of melatonin rose abruptly but then remained elevated for more than 60 hr in darkness. Melatonin secretion upon exposure to darkness did not conform to a circadian pattern and did not, therefore, support the hypothesis that pineal activity in reindeer is tightly regulated by circadian mechanisms. Instead the secretion of melatonin appeared to be acutely and directly sensitive to ambient lighting. The results are consistent with a model in which Arctic resident animals have adapted to extreme photic conditions by disconnecting the generation of the pineal melatonin signal from their circadian machinery and relying, instead, on its being driven by the LD cycle for just a few weeks annually in spring and autumn.


Assuntos
Adaptação Biológica/fisiologia , Comportamento Animal/fisiologia , Melatonina/sangue , Fotoperíodo , Rena/fisiologia , Estações do Ano , Animais , Regiões Árticas , Ritmo Circadiano/fisiologia
6.
Naturwissenschaften ; 94(3): 183-94, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17131139

RESUMO

Biological rhythms are a result of interplay between endogenous clocks and the ambient light-dark (LD) cycle. Biological timing in resident polar organisms presents a conundrum because these experience distinct daily LD cycles for only a few weeks each year. We measured locomotor activity in reindeer, Rangifer tarandus platyrhynchus (SR, n = 5 and 6) and R. tarandus tarandus (NR, n = 6), ranging freely at 78 and 70 degrees N, respectively, continuously throughout 1 year using data loggers. NR, but not SR, are gregarious which enabled us to examine the integrated effects of differences in social organisation and the photic environment at two different latitudes on the organisation of activity. In both sub-species, ultradian bouts of activity and inactivity alternated across the 24-h day throughout the year. This pattern was modified by the LD cycle in NR but barely at all in SR. Periodogram analysis revealed significant ultradian rhythmicity in both sub-species; the frequency of daily cycles of activity increased from three per day in winter to nearly five in summer. We conclude that this increase, and a concomitant increase in the level of daily activity, reflected the seasonal increase in the animals' appetite and the quality of their forage. Secondly, the combination, most evident in SR, of a weak photic response, weak circadian mechanisms and a weak social synchronization reduces the constraints of biological timing in an environment which is effectively non-rhythmic most of the year and permits expression of the basic ultradian pattern of ruminant activity. Third, the weaker 24-h rhythmicity in SR compared to NR indicates a latitudinal decrease in circadian organization and photic responsiveness in Rangifer.


Assuntos
Animais Selvagens , Ritmo Circadiano , Periodicidade , Rena/fisiologia , Animais , Clima Frio , Escuridão , Luz , Noruega
7.
Nature ; 438(7071): 1095-6, 2005 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-16371996

RESUMO

The light/dark cycle of day and night synchronizes an internal 'biological clock' that governs daily rhythms in behaviour, but this form of regulation is denied to polar animals for most of the year. Here we demonstrate that the continuous lighting conditions of summer and of winter at high latitudes cause a loss in daily rhythmic activity in reindeer living far above the Arctic Circle. This seasonal absence of circadian rhythmicity may be a ubiquitous trait among resident polar vertebrates.


Assuntos
Ritmo Circadiano/fisiologia , Ritmo Circadiano/efeitos da radiação , Escuridão , Rena/fisiologia , Estações do Ano , Luz Solar , Animais , Regiões Árticas , Comportamento Animal/fisiologia , Comportamento Animal/efeitos da radiação , Relógios Biológicos/fisiologia , Meio Ambiente , Rena/classificação , Fatores de Tempo
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