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1.
Eur Arch Psychiatry Clin Neurosci ; 274(3): 709-721, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37589727

RESUMO

Evidence for the effectiveness of physical activity (PA) in the treatment of depression prevails for outpatients with mild and moderate symptom levels. For inpatient treatment of severe depression, evidence-based effectiveness exists only for structured and supervised group PA interventions. The Step Away from Depression (SAD) study investigated the effectiveness of an individual pedometer intervention (PI) combined with an activity diary added to inpatient treatment as usual (TAU). In this multicenter randomized controlled trial, 192 patients were randomized to TAU or TAU plus PI. The two primary outcomes at discharge were depression-blindly rated with the Montgomery-Åsberg Depression Rating Scale (MADRS)-and average number of daily steps measured by accelerometers. Secondary outcomes were self-rated depression and PA, anxiety, remission and response rates. Multivariate analysis of variance (MANOVA) revealed no significant difference between both groups for depression and daily steps. Mean MADRS scores at baseline were 29.5 (SD = 8.3) for PI + TAU and 28.8 (SD = 8.1) for TAU and 16.4 (SD = 10.3) and 17.2 (SD = 9.9) at discharge, respectively. Daily steps rose from 6285 (SD = 2321) for PI + TAU and 6182 (SD = 2290) for TAU to 7248 (SD = 2939) and 7325 (SD = 3357). No differences emerged between groups in secondary outcomes. For severely depressed inpatients, a PI without supervision or further psychological interventions is not effective. Monitoring, social reinforcement and motivational strategies should be incorporated in PA interventions for this population to reach effectiveness.


Assuntos
Transtorno Depressivo , Pacientes Internados , Humanos , Depressão/terapia , Actigrafia , Resultado do Tratamento
2.
Nervenarzt ; 93(7): 742-753, 2022 Jul.
Artigo em Alemão | MEDLINE | ID: mdl-35781520

RESUMO

Sports psychiatry and psychotherapy is a relatively young field and is comprised of two key segments: the special features of the diagnostics and therapy of mental disorders in elite athletes and the use of exercise and sports in the development and treatment of mental disorders. Although all mental disorders can in principle also occur in (elite) athletes, there are additionally sport-specific mental disorders, such as anorexia athletica and other eating disorders, chronic traumatic encephalopathy, misuse of and dependency on performance-enhancing substances (doping) and muscle dysmorphia. Many high-quality clinical trials over the past two decades have been able to demonstrate a therapeutic efficacy of physical activity and sport in the treatment of various mental disorders. All clinicians active in psychiatry and psychotherapy should possess a basic knowledge of sports psychiatry.


Assuntos
Transtornos da Alimentação e da Ingestão de Alimentos , Psiquiatria , Esportes , Atletas , Humanos , Psicoterapia
3.
Eur Arch Psychiatry Clin Neurosci ; 271(2): 283-291, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32691135

RESUMO

In context of the current COVID-19 pandemic the consumption of pandemic-related media coverage may be an important factor that is associated with anxiety and psychological distress. Aim of the study was to examine those associations in the general population in Germany. 6233 participants took part in an online-survey (March 27th-April 6th, 2020), which included demographic information and media exploitation in terms of duration, frequency and types of media. Symptoms of depression, unspecific anxiety and COVID-19 related anxiety were ascertained with standardized questionnaires. Frequency, duration and diversity of media exposure were positively associated with more symptoms of depression and unspecific and COVID-19 specific anxiety. We obtained the critical threshold of seven times per day and 2.5 h of media exposure to mark the difference between mild and moderate symptoms of (un)specific anxiety and depression. Particularly the usage of social media was associated with more pronounced psychological strain. Participants with pre-existing fears seem to be particularly vulnerable for mental distress related to more immoderate media consumption. Our findings provide some evidence for problematical associations of COVID-19 related media exposure with psychological strain and could serve as an orientation for recommendations-especially with regard to the thresholds of critical media usage.


Assuntos
Ansiedade/epidemiologia , Ansiedade/psicologia , COVID-19/psicologia , Depressão/epidemiologia , Depressão/psicologia , Medo , Meios de Comunicação de Massa/estatística & dados numéricos , Pandemias , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Alemanha/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Angústia Psicológica , Inquéritos e Questionários , Adulto Jovem
4.
Philos Trans A Math Phys Eng Sci ; 378(2181): 20190366, 2020 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-32862814

RESUMO

The Arctic Ocean is considerably affected by the consequences of global warming, including more extreme seasonal fluctuations in the physical environment. So far, little is known about seasonality in Arctic marine ecosystems in particular microbial dynamics and cycling of organic matter. The limited characterization can be partially attributed to logistic difficulties of sampling in the Arctic Ocean beyond the summer season. Here, we investigated the distribution and composition of dissolved organic matter (DOM), gel particles and heterotrophic bacterial activity in the Fram Strait during summer and autumn. Our results revealed that phytoplankton biomass influenced the concentration and composition of semi-labile dissolved organic carbon (DOC), which strongly decreased from summer to autumn. The seasonal decrease in bioavailability of DOM appeared to be the dominant control on bacterial abundance and activity, while no temperature effect was determined. Additionally, there were clear differences in transparent exopolymer particles (TEP) and Coomassie Blue stainable particles (CSP) dynamics. The amount of TEP and CSP decreased from summer to autumn, but CSP was relatively enriched in both seasons. Our study therewith indicates clear seasonal differences in the microbial cycling of organic matter in the Fram Strait. Our data may help to establish baseline knowledge about seasonal changes in microbial ecosystem dynamics to better assess the impact of environmental change in the warming Arctic Ocean. This article is part of the theme issue 'The changing Arctic Ocean: consequences for biological communities, biogeochemical processes and ecosystem functioning'.


Assuntos
Bactérias/crescimento & desenvolvimento , Bactérias/metabolismo , Aquecimento Global , Compostos Orgânicos/análise , Água do Mar/química , Microbiologia da Água , Organismos Aquáticos/crescimento & desenvolvimento , Organismos Aquáticos/metabolismo , Regiões Árticas , Biomassa , Ciclo do Carbono , Ecossistema , Groenlândia , Modelos Biológicos , Noruega , Oceanos e Mares , Fitoplâncton/crescimento & desenvolvimento , Fitoplâncton/metabolismo , Estações do Ano
5.
Eur Arch Psychiatry Clin Neurosci ; 269(5): 529-542, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30194668

RESUMO

INTRODUCTION: While physical activity (PA) can play an important role in the treatment of mental disorders (MD), large proportions of patients with MD do not meet PA recommendations. The aim of this trial was to evaluate whether structured psychological intervention (MoVo-LISA) is effective in helping outpatients with MD to increase their level of PA. As active control group (CG) we modified MoVo-LISA to target healthy diet behavior. METHODS: N = 83 outpatients with MD (F1-F4) were randomized to the two conditions. PA (self-report and accelerometry), dietary behavior, social-cognitive determinants of health behavior change, psychiatric symptoms and health-related quality of life were assessed at baseline, 1 and 12 weeks after the intervention. RESULTS: Significant time*group interaction effects for objectively measured PA, dietary behavior and fruit and vegetable consumption indicated differential effects of the interventions on these outcomes. PA increased in the MoVo-LISA group (IG) from baseline to follow-up while it decreased in CG. IG showed a significant higher level of objectively measured PA at follow-up compared to CG. Dietary behavior and fruit and vegetable consumption significantly increased from baseline to follow-up in CG, but not IG. IG showed a significant increase in some, but not all social cognitive determinants of health behavior change. CONCLUSIONS: MoVo-LISA is effective in helping outpatients with MD to increase their level of PA in short- and mid-term. The used intervention strategies are effective for the promotion of healthy diet in patients with MD as well.


Assuntos
Dieta Saudável/psicologia , Exercício Físico/psicologia , Transtornos Mentais/psicologia , Qualidade de Vida/psicologia , Acelerometria , Adulto , Feminino , Comportamentos Relacionados com a Saúde , Promoção da Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Pacientes Ambulatoriais/psicologia , Autorrelato
6.
Ecology ; 99(5): 1108-1118, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29453803

RESUMO

A key challenge in ecology is to understand how nutrients and light affect the biodiversity and community structure of phytoplankton and plant communities. According to resource competition models, ratios of limiting nutrients are major determinants of species composition. At high nutrient levels, however, species interactions may shift to competition for light, which might make nutrient ratios less relevant. The "nutrient-load hypothesis" merges these two perspectives, by extending the classic model of competition for two nutrients to include competition for light. Here, we test five key predictions of the nutrient-load hypothesis using multispecies competition experiments. A marine phytoplankton community sampled from the North Sea was inoculated in laboratory chemostats provided with different nitrogen (N) and phosphorus (P) loads to induce either single resource limitation or co-limitation of N, P, and light. Four of the five predictions were validated by the experiments. In particular, different resource limitations favored the dominance of different species. Increasing nutrient loads caused changes in phytoplankton species composition, even if the N:P ratio of the nutrient loads remained constant, by shifting the species interactions from competition for nutrients to competition for light. In all treatments, small species became dominant whereas larger species were competitively excluded, supporting the common view that small cell size provides a competitive advantage under resource-limited conditions. Contrary to expectation, all treatments led to coexistence of diatoms, cyanobacteria and green algae, resulting in a higher diversity of species than predicted by theory. Because the coexisting species comprised three phyla with different photosynthetic pigments, we speculate that niche differentiation in the light spectrum might play a role. Our results show that mechanistic resource competition models that integrate nutrient-based and light-based approaches provide an important step forward to understand and predict how changing nutrient loads affect community composition.


Assuntos
Diatomáceas , Fitoplâncton , Biodiversidade , Nutrientes , Fósforo
7.
Psychooncology ; 27(3): 757-767, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-28805954

RESUMO

OBJECTIVE: Although caregiver burden may continue to influence the mental health of cancer patients' caregivers long after bereavement, few studies have examined this issue. METHODS: A systematic review was conducted to provide a summary of (1) operationalizations of caregiver burden used in this field and (2) the effect of caregiver burden on postbereavement mental health of adult caregivers of cancer patients. A systematic search of the electronic databases PubMed, Web of Science, and PsycINFO was conducted across empirical studies published in a peer-reviewed journal up until April 2017. RESULTS: Caregiver burden was rarely defined, and it was operationalized in multiple and diverging ways. The 20 included papers present varying results but generally indicate that caregiver burden (especially emotional) has an adverse effect on postbereavement mental health. CONCLUSIONS: In future studies, researchers seeking to ascertain which aspects of caregiver burden may prove an appropriate target for prevention and intervention should first use a precise operational definition of the concept.


Assuntos
Luto , Cuidadores/psicologia , Efeitos Psicossociais da Doença , Neoplasias/psicologia , Adaptação Psicológica , Adulto , Idoso , Humanos , Masculino , Saúde Mental , Pessoa de Meia-Idade
8.
BMC Psychiatry ; 18(1): 52, 2018 02 27.
Artigo em Inglês | MEDLINE | ID: mdl-29482525

RESUMO

BACKGROUND: Approximately 10% of the individuals experiencing the death of a loved one develop prolonged grief disorder (PGD) after bereavement. Family members of haematological cancer patients might be particularly burdened since their loss experience is preceded by a very strenuous time of disease and aggressive treatment. However, support needs of relatives of cancer patients often remain unmet, also after the death of the patient. Therapeutic possibilities are enhanced by providing easily available and accessible Internet-based therapies. This study will adapt and evaluate an Internet-based grief therapy for bereaved individuals after the loss of a significant other due to haematological cancer. METHODS: The efficacy of the Internet-based grief therapy is evaluated in a randomized controlled trial with a wait-list control group. Inclusion criteria are bereavement due to hematological cancer and meeting the diagnostic criteria for PGD. Exclusion criteria are severe depression, suicidality, dissociative tendency, psychosis, posttraumatic stress disorder, substance use disorder, and current psychotherapeutic or psychopharmacological treatment. The main outcome is PGD severity. Secondary outcomes are depression, anxiety, somatization, posttraumatic stress, quality of life, sleep quality, and posttraumatic growth. Data is collected pre- and posttreatment. Follow-up assessments will be conducted 3, 6, and 12 months after completion of the intervention. The Internet-based grief therapy is assumed to have at least moderate effects regarding PGD and other bereavement-related mental health outcomes. Predictors and moderators of the treatment outcome and PGD will be determined. DISCUSSION: Individuals bereaved due to haematological cancer are at high risk for psychological distress. Tailored treatment for this particularly burdened target group is missing. Our study results will contribute to a closing of this healthcare gap. TRIAL REGISTRATION: German Clinical Trial Register UTN: U1111-1186-6255 . Registered 1 December 2016.


Assuntos
Luto , Família/psicologia , Neoplasias Hematológicas/psicologia , Internet , Terapia Assistida por Computador/métodos , Adulto , Ansiedade/psicologia , Ansiedade/terapia , Terapia Cognitivo-Comportamental/métodos , Depressão/psicologia , Depressão/terapia , Feminino , Seguimentos , Pesar , Neoplasias Hematológicas/terapia , Humanos , Internet/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Psicoterapia/métodos , Qualidade de Vida/psicologia , Transtornos de Estresse Pós-Traumáticos/psicologia , Resultado do Tratamento
10.
Phys Chem Chem Phys ; 15(48): 20876-86, 2013 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-24196523

RESUMO

Air pollution by nitrogen oxides represents a serious environmental problem in urban areas where numerous sources of these pollutants are concentrated. One approach to reduce the concentration of these air pollutants is their light-induced oxidation in the presence of molecular oxygen and a photocatalytically active building material which uses titanium dioxide as the photocatalyst. Herein, results of an investigation concerning the influence of the photon flux and the pollutant concentration on the rate of the photocatalytic oxidation of nitrogen(ii) oxide in the presence of molecular oxygen and UV(A) irradiated titanium dioxide powder are presented. A Langmuir-Hinshelwood-type rate law for the photocatalytic NO oxidation inside the photoreactor comprising four kinetic parameters is derived being suitable to describe the influence of the pollutant concentration and the photon flux on the rate of the photocatalytic oxidation of nitrogen(ii) oxide.


Assuntos
Óxido Nitroso/química , Processos Fotoquímicos/efeitos da radiação , Titânio/química , Raios Ultravioleta , Catálise/efeitos da radiação , Cinética , Oxirredução/efeitos da radiação , Oxigênio/química , Propriedades de Superfície
11.
Microorganisms ; 11(9)2023 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-37764141

RESUMO

Salmonella are important pathogenic bacteria and, following Campylobacter, they are the second most common cause of bacterial foodborne infections worldwide. To reduce the presence of bacteria along the food chain, the application of bacteriophages (phages) may be a promising tool. In this study, the lytic properties of six phages against five relevant Salmonella serotypes (S. Enteritidis, S. Typhimurium, S. Infantis, S. Paratyphi B and S. Indiana) were analyzed. Three phages were able to lyse all five serotypes. We determined the lytic potential of each phage on indicator strains in vitro at room temperature (RT) and at 37 °C using low multiplicities of infection (MOIs). Most phages reduced their host more efficiently at RT than at 37 °C, even at the lowest MOI of 0.001. Following this, the lytic activity of a cocktail comprising five phages (MOI = 0.1) was examined with each of the five serotypes and a mix of them at RT, 15, 12, 10, 8 and 6 °C. All cultures of single serotypes as well as the mixture of strains were significantly reduced at temperatures as low as 8 °C. For single serotypes, reductions of up to 5 log10 units and up to 2.3 log10 units were determined after 6 h (RT) and 40 h (8 °C), respectively. The mixture of strains was reduced by 1.7 log10 units at 8 °C. The data clearly suggest that these phages are suitable candidates for biocontrol of various Salmonella serotypes under food manufacturing conditions.

12.
Neural Dev ; 17(1): 12, 2022 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-36419086

RESUMO

BACKGROUND: Neurons are highly specialized cells with a complex morphology generated by various membrane trafficking steps. They contain Golgi outposts in dendrites, which are formed from somatic Golgi tubules. In trafficking membrane fusion is mediated by a specific combination of SNARE proteins. A functional SNARE complex contains four different helices, one from each SNARE subfamily (R-, Qa, Qb and Qc). Loss of the two Qb SNAREs vti1a and vti1b from the Golgi apparatus and endosomes leads to death at birth in mice with massive neurodegeneration in peripheral ganglia and defective axon tracts. METHODS: Hippocampal and cortical neurons were isolated from Vti1a-/- Vti1b-/- double deficient, Vti1a-/- Vti1b+/-, Vti1a+/- Vti1b-/- and Vti1a+/- Vti1b+/- double heterozygous embryos. Neurite outgrowth was determined in cortical neurons and after stimulation with several neurotrophic factors or the Rho-associated protein kinase ROCK inhibitor Y27632, which induces exocytosis of enlargeosomes, in hippocampal neurons. Moreover, postsynaptic densities were isolated from embryonic Vti1a-/- Vti1b-/- and Vti1a+/- Vti1b+/- control forebrains and analyzed by western blotting. RESULTS: Golgi outposts were present in Vti1a-/- Vti1b+/- and Vti1a+/- Vti1b-/- dendrites of hippocampal neurons but not detected in the absence of vti1a and vti1b. The length of neurites was significantly shorter in double deficient cortical neurons. These defects were not observed in Vti1a-/- Vti1b+/- and Vti1a+/- Vti1b-/- neurons. NGF, BDNF, NT-3, GDNF or Y27632 as stimulator of enlargeosome secretion did not increase the neurite length in double deficient hippocampal neurons. Vti1a-/- Vti1b-/- postsynaptic densities contained similar amounts of scaffold proteins, AMPA receptors and NMDA receptors compared to Vti1a+/- Vti1b+/-, but much more TrkB, which is the receptor for BDNF. CONCLUSION: The absence of Golgi outposts did not affect the amount of AMPA and NMDA receptors in postsynaptic densities. Even though TrkB was enriched, BDNF was not able to stimulate neurite elongation in Vti1a-/- Vti1b-/- neurons. Vti1a or vti1b function as the missing Qb-SNARE together with VAMP-4 (R-SNARE), syntaxin 16 (Qa-SNARE) and syntaxin 6 (Qc-SNARE) in induced neurite outgrowth. Our data show the importance of vti1a or vti1b for two pathways of neurite elongation.


Assuntos
Receptores de N-Metil-D-Aspartato , Proteínas SNARE , Animais , Camundongos , Amidas , Neurônios , Proteínas Qb-SNARE
13.
Int J Methods Psychiatr Res ; 30(1): e1862, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33180994

RESUMO

OBJECTIVES: Increasing the number of daily steps by using a pedometer and a diary leads to an activity increase and improved health outcomes in a variety of somatic disorders. Hence, for the inpatient treatment of depression, supervised exercise interventions are more widespread. We aim to examine if a self-managed pedometer intervention (PI) with the option of being proceeded after discharge leads to reduction of depression and to a physical activity (PA) increase. METHODS: The Step Away from Depression (SAD) study is a multicenter randomized controlled trial targeting 400 patients with major depressive disorder. Treatment as usual (TAU) is compared to TAU plus PI after 4 weeks, at discharge, and 6 months after hospital admission. Primary outcomes are clinically rated depression severity and accelerometer-measured step counts. Secondary outcomes include self-reported depression symptoms and PA level, psychiatric symptoms, health-related quality of life, self-efficacy, and components of the Motivation Volition Process Model. RESULTS: We report the design of the SAD study considering several methodological aspects for exercise studies, in general. CONCLUSIONS: Results of our study will provide information about efficacy of PI for inpatient treatment and about interrelating processes of change concerning depression, PA, and aspects of motivation and volition.


Assuntos
Actigrafia , Transtorno Depressivo Maior , Depressão/terapia , Transtorno Depressivo Maior/terapia , Exercício Físico , Humanos , Estudos Multicêntricos como Assunto , Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto
14.
Sci Rep ; 10(1): 20599, 2020 11 26.
Artigo em Inglês | MEDLINE | ID: mdl-33244136

RESUMO

The main source of marine organic carbon (OC) is autotrophic production, while heterotrophic degradation is its main sink. Increased anthropogenic CO2 release leads to ocean acidification and is expected to alter phytoplankton community composition, primary production rates and bacterial degradation processes in the coming decades with potential consequences for dissolved and particulate OC concentration and composition. Here we investigate effects of increased pCO2 on dissolved and particulate amino acids (AA) and carbohydrates (CHO), in arctic and sub-arctic planktonic communities in two large-scale mesocosm experiments. Dissolved AA concentrations responded to pCO2/pH changes during early bloom phases but did not show many changes after nutrient addition. A clear positive correlation in particulate AA was detected in post-bloom phases. Direct responses in CHO concentrations to changing pCO2/pH were lacking, suggesting that observed changes were rather indirect and dependent on the phytoplankton community composition. The relative composition of AA and CHO did not change as a direct consequence of pCO2 increase. Changes between bloom phases were associated with the prevailing nutrient status. Our results suggest that biomolecule composition will change under future ocean conditions but responses are highly complex, and seem to be dependent on many factors including bloom phase and sampling site.

15.
Brain Behav ; 10(9): e01745, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32633464

RESUMO

BACKGROUND: The current COVID-19 pandemic comes with multiple psychological stressors due to health-related, social, economic, and individual consequences and may cause psychological distress. The aim of this study was to screen the population in Germany for negative impact on mental health in the current COVID-19 pandemic and to analyze possible risk and protective factors. METHODS: A total of 6,509 people took part in an online survey in Germany from 27 March to 6 April. The questionnaire included demographic information and ascertained psychological distress, anxiety and depressive symptoms, and risk and protective factors. RESULTS: In our sample, over 50% expressed suffering from anxiety and psychological distress regarding the COVID-19 pandemic. Participants spent several hours per day thinking about COVID-19 (M = 4.45). Psychological and social determinants showed stronger associations with anxiety regarding COVID-19 than experiences with the disease. CONCLUSIONS: The current COVID-19 pandemic does cause psychological distress, anxiety, and depression for large proportions of the general population. Strategies such as maintaining a healthy lifestyle and social contacts, acceptance of anxiety and negative emotions, fostering self-efficacy, and information on where to get medical treatment if needed, seem of help, while substance abuse and suppression of anxiety and negative emotions seem to be associated with more psychological burden.


Assuntos
Ansiedade/psicologia , COVID-19/psicologia , Saúde Mental , Angústia Psicológica , Resiliência Psicológica , Estresse Psicológico/psicologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Depressão/psicologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pandemias , Medição de Risco , Inquéritos e Questionários , Adulto Jovem
16.
BJPsych Open ; 6(5): e91, 2020 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-32812525

RESUMO

The coronavirus disease 2019 (COVID-19) pandemic may cause psychological distress in the general population and has the potential to cause anxiety regarding COVID-19. No validated questionnaires exist for the measurement of specific COVID-19 anxiety. We modified the DSM 5 - Severity Measure for Specific Phobia-Adult scale specifically for anxiety regarding COVID-19, and report the psychometric properties from an online study with 6262 participants from the general population in Germany. We analysed internal consistency as well as concordant validity. The scale showed good internal consistency (α = 0.86) and good concordant validity (rs = 0.60) with the 2-item Generalized Anxiety Disorder measure and rs = 0.61 with self-rating of limitations in daily life caused by COVID-19 anxiety.

17.
Porcine Health Manag ; 6: 19, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32832096

RESUMO

BACKGROUND: A Voluntary Human Approach Test (VHAT) was performed in pig pens, and relationships between environmental conditions and welfare indicators were investigated. Five variables were measured in 1668 pens in 214 fattening pig herds in Germany: time until the first contact (touching) between a pig and the person in the pen (TUFC), time until the observer was surrounded by pigs within a radius of approximately two meters, percentage of pigs relative to group size [%] surrounding the observer after 1 min (PPSO), percentage of pigs relative to group size [%] that completely avoided contact with the observer during the entire test period, and how the pigs contacted the observer (Score 0 [no touching] - 3 [biting]). Furthermore, variables indicative of the pigs' environment (e.g., feeding system, ventilation system), management (e.g., number of usable drinkers, number of usable manipulatable materials), and welfare (e.g., tail lesions, ear lesions) were documented. RESULTS: Pigs engaging in more forceful means of contact (nibbling, biting) approached the observer faster than those exhibiting more gentle types of contact (touching). A lower TUFC was associated with more manipulatable materials present, a higher number of drinkers, and with the control position of the caretaker located inside the pen. Pigs kept in larger groups showed a lower TUFC than those in smaller groups (P = 0.0191). However, PPSO was lower in pigs kept in smaller groups (1-12 pigs per pen) with more manipulatable materials available. In groups with low PPSOs, more tail lesions were observed (P = 0.0296). No relationship between contact type and tail or ear injuries was detected. In younger pigs, PPSO was higher (49.9 ± 23.2%) than for animals in the second half of the fattening period (45.1 ± 19.9%). CONCLUSIONS: In this on-farm study, the relationships between VHAT behavior and environmental factors revealed that external factors (e.g., management practices, housing conditions) impact animals' responses to this behavioral test. Therefore, using the VHAT as an animal welfare indicator is valid only if these variables are studied as well.

18.
Front Microbiol ; 8: 1299, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28747905

RESUMO

One of the major challenges in ecological stoichiometry is to establish how environmental changes in resource availability may affect both the biochemical composition of organisms and the species composition of communities. This is a pressing issue in many coastal waters, where anthropogenic activities have caused large changes in riverine nutrient inputs. Here we investigate variation in the biochemical composition and synthesis of amino acids, fatty acids (FA), and carbohydrates in mixed phytoplankton communities sampled from the North Sea. The communities were cultured in chemostats supplied with different concentrations of dissolved inorganic nitrogen (DIN) and phosphorus (DIP) to establish four different types of resource limitations. Diatoms dominated under N-limited, N+P limited and P-limited conditions. Cyanobacteria became dominant in one of the N-limited chemostats and green algae dominated in the one P-limited chemostat and under light-limited conditions. Changes in nutrient availability directly affected amino acid content, which was lowest under N and N+P limitation, higher under P-limitation and highest when light was the limiting factor. Storage carbohydrate content showed the opposite trend and storage FA content seemed to be co-dependent on community composition. The synthesis of essential amino acids was affected under N and N+P limitation, as the transformation from non-essential to essential amino acids decreased at DIN:DIP ≤ 6. The simple community structure and clearly identifiable nutrient limitations confirm and clarify previous field findings in the North Sea. Our results show that different phytoplankton groups are capable of adapting their key biosynthetic rates and hence their biochemical composition to different degrees when experiencing shifts in nutrient availability. This will have implications for phytoplankton growth, community structure, and the nutritional quality of phytoplankton as food for higher trophic levels.

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