Carnitina dietética mantem reservas energéticas e evita a fatiga de bagre-africano durante exercício

Lipídios e proteínas são tradicionalmente considerados combustíveis primários durante natação aeróbica. Nesse ensaio foi investigado o efeito da suplementação de vários níveis de gordura e carnitina no metabolismo de 100 bagres africanos juvenis (Clarias gariepinus). Os peixes foram arraçoados com quatro dietas isoprotéicas, cada uma contendo 100 ou 190 g gordura kg-1 dieta, e um dos dois níveis de carnitina (15 e 1000 mg kg-1). Os peixes cresceram de 61 a 162 g em 10 semanas. No final do ensaio de alimentação, grupos de seis peixes por tratamento foram induzidos a nadar vigorosamente por 3 h e em seguida vários parâmetros foram determinados no tecido muscular e plasma, e os resultados observados nos grupos exercitados foram comparados com grupos controles (não exercitados). Os peixes arraçoados com 1,000 mg carnitina acumularam de duas a três vezes mais carnitina que os peixes arraçoados com 15 mg carnitina. O nível de acyl-carnitina no plasma foi influenciado pela interação entre os tratamentos dietéticos e exercício físico (P < 0.05). As concentrações de adenosina trifosfato (ATP) e fosfocreatina no tecido muscular branco (WM) foram mais elevadas em peixes arraçoados com alto nível de carnitina dietética, mas só aqueles peixes exercitados (P < 0.05). Os peixes arraçoados com 190 g gordura e 1,000 mg carnitina obtiveram um nível elevado de potencial energético adenilado (AEC) e uma redução da concentração de amônia plasmática. A suplementação de carnitina dietética é importante para peixes criados em sistemas intensivos e em fase inicial de crescimento, uma situação típica que o consumo de gordura é elevado. A utilização de dietas ricas em carnitina poderá evitar que o animal vivencie uma redução brusca das reservas energéticas, durante períodos de atividade física exaustiva, um estresse fisiológico relativamente comum no habitat natural e em sistemas de aqüicultura intensiva.Lipids, together with proteins, are traditionally considered as primary fuels during aerobic swimming. The effects of dietary fat and carnitine supplements and exercise on the energy metabolism of juvenile fish were investigated. One hundred African catfish (Clarias gariepinus) were fed four isonitrogenous diets containing a fat level of 100 or 190 g kg-1 diet and one of the two levels of carnitine (15 and 1000 mg kg-1). Fish grew from 61 to 162 g in 10 wk. Thereafter, 6 fish per group swam vigorously for 3 h and the results were compared with unexercised groups. Fish receiving 1,000 mg carnitine accumulated 2- to 3-fold more carnitine than fish receiving 15 mg carnitine. Plasma acyl-carnitine level was affected by an interaction between dietary treatment and exercise (P < 0.05). Adenosine triphosphate and phosphocreatine concentrations were higher in the white muscle (WM) of exercised fish fed the high-carnitine supplements, compared with the low-carnitine fed fish (P < 0.05). Adenilate energy charge indexes were higher and ammonia concentrations were lower in WM of fish fed high-carnitine and high-fat diets. Dietary carnitine supplements may be needed in growing fish when dietary lipid level is high. In that case extra dietary carnitine can maintain the body energy reserves at adequate level when fish is exposed to a short-term, exhaustive exercise, a physiologic stress common both in nature and in intensive aquaculture systems

Desempenho de juvenis de pregado (Scophthalmus maximus) em função da densidade de estocagem e de níveis dietéticos de L-carnitina

A aquicultura de pregado (Scophthalmus maximus) utilizando elevadas densidades pode reduzir o crescimento e aumentar os custos de produção. Elevados níveis de metabolitos gerados nestes sistemas intensivos provocam rápida deterioração da qualidade da água, podendo também comprometer a performance da produção. A L-carnitina atua como potenciadora do crescimento parecendo ser promissora por atenuar alguns desses efeitos. Os efeitos de densidades (4, 8, 11 e 14 kg m²) no desempenho do crescimento, composição corporal foram avaliados em pregados (75,6 ± 2,8 g) alimentados durante 75 dias a dois níveis dietéticos de L-carnitina (40 ou 240 mg kg¹). Após esse período, determinou-se a excreção de amônia pós-prandial durante 24 horas. Os peixes cultivados na menor densidade, 4 kg m², apresentaram melhores taxas de crescimento e ganho de peso (94-96 g) em comparação aos mantidos em altas densidades (80-87 g). A taxa de eficiência proteica foi mais elevada a 4 kg m² (1,33-1,36), do que a densidades de 8 kg m² (0,98) ou 14 kg m² (0,45). A ingestão voluntária de alimento decresceu de 0,70 para 0,56% do peso corporal com o incremento da densidade. A suplementação de carnitina não afetou o crescimento e a composição corporal, com exceção do conteúdo de carnitine da carcaça que passou de 75 a 128 mg kg¹. Peixes alimentados com suplementos de 240 mg L-carnitina apresentam excreção de amônia mais baixa comparativamente aos alimentados com 40 mg L-carnitina (p < 0,05).Commercial farming of turbot (Scophthalmus maximus) at high stocking densities may lead to growth depression and increasing production costs. Moreover, the high levels of accumulated waste in an intensive system may cause rapid deterioration of water quality, which may undermine the production. L-carnitine is known as a growth-enhancer which shows promise as mitigator of crowding effects. The effects of stocking densities (4, 8, 11 and 14 kg m²) on growth performance, feed utilization and body composition were evaluated during 75 days on turbot (75.6 ± 2.8 g) fed two dietary L-carnitine levels (40 or 240 mg kg¹). At the end of the feeding trial, total ammonia excretion (TAN) was measured postprandially for 24h. Specific growth rate and weight gain decreased with increasing stocking density. Fish held at 4 kg m² had higher final body weight (94-96 g) than fish held at higher densities (80-87 g). Protein efficiency ratio was higher in fish held at 4 kg m² (1.33-1.36), in comparison to fish stocked at 8 kg m² (0.98) or 14 kg m² (0.45). Voluntary feed intake decreased from 0.70 to 0.56% BW with increasing stocking density. Dietary L-carnitine supplementation did not affect growth performance and body composition, except for body L-carnitine content which increased from 75 to 128 mg kg¹ BW with supplementation. Fish fed 240 mg L-carnitine supplements had lower TAN that the ones fed 40 mg L-carnitine (p < 0.05)

Separate and combined effects of cyclic fasting and l-carnitine supplementation in red porgy (Pagrus pagrus, L. 1758)

We examined the e¡ects of cyclic fasting in red porgy (Pagrus pagrus) fed di¡erent dietary carnitine levels. Ju venile ¢sh (23.58 3.49 g) were divided into eight groups ^ four groups were fed every day to apparent sa tiation, while the other four were fasted for 7 days every 2 weeks. In each feeding regime, two replicates were fed an L-carnitine non-supplemented diet (46 mg kg 1 ) and the other two groups were fed an L-carnitine sup plemented diet (630 mg kg 1 ). Fish fed 630 mg L-carni tine accumulated two times more L-carnitine in muscle than ¢sh fed 46 mg L-carnitine. Cyclic fasting reduced the growth performance and lipid content in the liver. Carnitine supplementation did not a¡ect performance and body composition, but decreased the n-6 PUFA content. Moreover, the combined e¡ects of fasting and carnitine supplementation were observed on reducing the n-3 fatty acid content. Areas of steatosis were found in the livers of red porgy, but the results revealed that supplementation of L-carnitine in cyclic fasted ¢sh con tributed towards a lower degree of vacuolization than in ¢sh fed to apparent satiation. Regardless of the feed ing regime applied, the spleen of ¢sh fed the L-carni tine-supplemented diet was haemorrhagic and hyper activation of melanomacrophage cells was observed.info:eu-repo/semantics/publishedVersio

Molecular and functional characterization of a fads2 orthologue in the Amazonian teleost, Arapaima gigas

The Brazilian teleost Arapaima gigas is an iconic species of the Amazon. In recent years a significant effort has been put into the farming of arapaima to mitigate overfishing threats. However, little is known regarding the nutritional requirements of A. gigas in particular those for essential fatty acids including the long-chain polyunsaturated fatty acids (LC-PUFA) eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). The ability to biosynthesize LC-PUFA is dependent upon the gene repertoire of fatty acyl desaturases (Fads) and elongases (Elovl), as well as their fatty acid specificities. In the present study we characterized both molecularly and functionally an orthologue of the desaturase fatty acid desaturase 2 (fads2) from A. gigas. The isolated sequence displayed the typical desaturase features, a cytochrome b5-domain with the heme-binding motif, two transmembrane domains and three histidine-rich regions. Functional characterization of A. gigas fads2 showed that, similar to other teleosts, the A. gigas fads2 exhibited a predominant &Delta;6 activity complemented with some capacity for &Delta;8 desaturation. Given that A. gigas belongs to one of the oldest teleostei lineages, the Osteoglossomorpha, these findings offer a significant insight into the evolution LC-PUFA biosynthesis in teleosts

Solid-state fermentation of plant feedstuff mixture affected the physiological responses of European seabass (Dicentrarchus labrax) reared at different temperatures and subjected to salinity oscillation

This study aimed to evaluate the effects of dietary inclusion of plant feedstuff mixture (PFM) pre-treated by solid-state fermentation (SSF) on the physiological responses of European seabass. For that purpose, two diets were formulated to contain: 20% inclusion level of non-fermented plant ingredients mixture (20Mix) and 20Mix fermented by A. niger in SSF conditions (20Mix-SSF). Seabass juveniles (initial body weight: 20.9 ± 3.3 g) were fed the experimental diets, reared at two different temperatures (21 and 26 °C) and subjected to weekly salinity oscillations for six weeks. Growth performance, digestive enzyme activities, humoral immune parameters, and oxidative stress indicators were evaluated. A reduction in weight gain, feed intake, and thermal growth coefficient was observed in fish fed the fermented diet (20Mix-SSF). Salinity oscillation led to an increase in weight gain, feed efficiency, daily growth index, and thermal growth coefficient, regardless of dietary treatment. Higher rearing temperatures also increased daily growth index. No dietary effect was observed on digestive enzymes activities, whereas rearing temperature and salinity oscillation modulated digestive enzyme activities. Oxidative stress responses were significantly affected by experimental diets, temperature, and salinity conditions. Catalase and glutathione peroxidase activities showed an interactive effect. Fish reared at 21 °C showed higher enzymatic activity when fed the 20Mix-SSF. Conversely, fish reared at 26 °C showed higher GPx activity when fed the 20Mix diet. Fish reared at 26 °C showed reduced peroxidase and lysozyme activities, while salinity fluctuation led to increased lysozyme activity and decreased ACH50 activity. ACH50 activity increased in fish fed the 20Mix-SSF. Overall, the dietary inclusion of PFM fermented by A. niger was unable to mitigate the impact of environmental stress on physiological performance in European seabass. In fact, fermented feed caused an inhibition of growth performances and an alteration of some physiological stress indicators.This work was funded by the Ocean3R project (NORT-01-0145-FEDER-000064), supported by the North Portugal Regional Operational Program (NORT2020), under the PORTUGAL 2020 Partnership Agreement and through the European Regional Development Fund (ERDF). This research was partially supported by national funds through FCT—Foundation for Science and Technology within the scope of UIDB/04423/2020 and UIDP/04423/2020.info:eu-repo/semantics/publishedVersio

Efeitos da suplementação com vitamina E na cicatrização de feridas induzidas em Oreochromis niloticus

In the present study, the effect of vitamin E supplementation 450 mg/kg diet was appraised in the process of induced wound healing in Nile tilapias Oreochromis niloticus. Fish were distributed into 18 tanks (10 fish each). Nine tanks were fed the non-supplemented diet and the other 9 tanks were fed 450 mg vitamin E for 60 days. Subsequently, the fish were anesthetized and the epidermis and dermis were surgically removed. The rate of cicatricial retraction and appearance of the wounds, and the histomorphometry of mucous cells, chromatophores, revascularization, inflammatory cells, presence of fibroblasts, collagen fibers, and scales were checked after 3-, 7-, 14-, 21-, and 28 days post-wounding. The retraction rate of the wound was significantly higher in the supplemented fish. The higher concentrations of inflammatory cells, mucous cells, and chromatophores, as well as the production and organization of collagen fibers, resulted in a higher retraction rate. We concluded that a dietary supplementation diet improves specific aspects of the cutaneous healing process in Nile tilapia fish.No presente estudo, o efeito da suplementação com vitamina E de 450 mg / kg de dieta foi avaliado no processo de cicatrização induzida de feridas em tilápias do Nilo, Oreochromis niloticus. Os peixes foram distribuídos em 18 tanques (N=10), sendo 9 tanques com dieta não suplementada e os outros 9 tanques suplementados com 450 mg de vitamina E por 60 dias. Posteriormente, os peixes foram anestesiados e a epiderme e derme foram removidas cirurgicamente. Nos tempos pré- determinado de 3, 7, 14, 21 e 28 dias após a ferida foi analisado a taxa de retração cicatricial, a aparência das feridas e a histomorfometria das células mucosas, dos cromatóforos, das células inflamatórias, a revascularização, a presença de fibroblastos, de fibras de colágeno e escamas. A taxa de retração da ferida foi significativamente maior nos peixes suplementados. As maiores concentrações de células inflamatórias, mucosas e cromatóforos, bem como a produção e organização das fibras de colágeno, resultaram em uma maior taxa de retração. Concluímos que a dieta de suplementação melhora aspectos específicos do processo de cicatrização cutânea em peixes de tilápia do Nilo

Combined effects of temperature and dietary lipid level on body composition, growth, and freshness profile in european seabass, dicentrarchus labrax

The effects of increasing temperature and dietary lipid level on the body composition, growth performance, and freshness profile of the European seabass (Dicentrarchus labrax) were evaluated through a fish trial lasting 56 days. Findings demonstrated that fish reared at 24 °C presented a lower lipid level and a higher daily growth index than those reared at 20 °C. On the other hand, the sea bass condition index did not change among treatments. Additionally, sensory analysis (the Quality Index Method) and microbiological analysis revealed that fish reared at 24 °C showed better freshness conditions than those at 20 °C. Nevertheless, the dietary lipid level did not have any influence on fish freshness conditions. Therefore, our data suggest that the increase in temperature to 24 °C is beneficial for the growth and freshness profile of this particular species in aquaculture.info:eu-repo/semantics/publishedVersio

Elemental composition and bioaccessibility of farmed oysters (Crassostrea gigas) fed different ratios of dietary seaweed and microalgae during broodstock conditioning

Free PMC article: https://www.ncbi.nlm.nih.gov/pmc/articles/pmid/31428337/[Correction added on 8 July 2019, after first online publication: New affiliation was added for Jorge Machado, José Fernando Gonçalves, and Paulo Vaz‐Pires.]The Pacific oyster (Crassostrea gigas) culture has been expanding, thereby leading to a greater importance of hatcheries. Broodstock conditioning is very important in the hatchery process, in which diet composition may have a strong influence on the offspring production and quality. Therefore, the current study evaluated elemental composition and bioaccessibility of oysters fed different ratios of dietary seaweed (SW) and microalgae. The dietary conditioning consisted of direct replacement of microalgae by SW at four substitution levels (0%, 25%, 50%, and 100% diet). It was observed that oysters fed 100% SW had the highest levels of Be, Cu, Zn, Sr, and Cd. The most important trend was a concentration decline of most elements with progressively lower levels of SW substitution for microalgae in the feeds. No Cd or Pb hazard (contents below 1.0 mg/kg for Cd and 1.5 mg/kg for Pb) was found in oyster meat. Regarding elemental bioaccessibility, values were similar, near 100% in the cases of Cu, Br, and I. Only for Mn and Pb, bioaccessibility percentages deviated more from 100%. Indeed, the value for Pb was 50% ± 7% (initial group), and for Mn, all values were equal or lower than 29% ± 2% (final group of oysters fed microalgae). It was observed that Mn, Cd, and Pb bioaccessibility increased with a growing share of microalgal biomass in the feed. Therefore, this study showed that SW incorporation into the feed influences elemental composition and bioaccessibility of the oysters.The current study was supported by Project INNOVMAR— Innovation and Sustainability in the Management and Exploitation of Marine Resources (NORTE‐01‐0145‐FEDER‐000035) within the line “INSEAFOOD, Innovation and valorization of seafood products,” funded by the Northern Regional Operational Programme (NORTE2020) through the European Regional Development Fund (ERDF). Moreover, the study was funded by the project AQUAMAX (Ref. 16‐02‐01‐FMP‐0047). This work was also supported by the following Postdoctoral Grants: Ref.: SFRH/BPD/102689/2014 (“Fundação para a Ciência e a Tecnologia,” FCT) for the author Carlos Cardoso, Ref.: SFRH/BD/129795/2017 (“Fundação para a Ciência e a Tecnologia,” FCT) for the author Joana Matos, and DIVERSIAQUA (MAR2020) for the author Cláudia Afonso.info:eu-repo/semantics/publishedVersio

Amicus curiae on the request for an advisory opinion concerning the figure of the political judgment or impeachment presented by the Inter-American Commission on Human Rights

O presente trabalho diz respeito à solicitação de Opinião Consultiva feita pela Comissão Interamericana de Direitos Humanos (CIDH) acerca dos julgamentos políticos e impeachment, de modo a fomentar e ampliar o debate sobre o tema. Nesse sentido, o Núcleo Constitucionalismo e Democracia, que integra o Centro de Estudos da Constituição (CCONS), do Programa de Pós-Graduação em Direito da Universidade Federal do Paraná (UFPR), e o Departamento de Direito Constitucional da Universidade Externado da Colômbia, ingressaram, em conjunto, como amicus curiae, e apresentaram esta opinião diante da Comissão Interamericana com o propósito de colaborar, teórica e praticamente, com o Sistema Interamericano de Direitos Humanos (SIDH). Na primeira parte do trabalho faz-se uma série de observações sobre a consulta formulada pela CIDH, inclusive quanto às próprias regras e estrutura do procedimento da função consultiva. Na segunda parte, faz-se referência ao papel e legitimidade dos tribunais internacionais e, concretamente, da Corte Interamericana de Direitos Humanos (Corte IDH), na proteção da democracia e dos direitos políticos. Na terceira parte, responde-se ao objeto central da consulta, sobre as garantias judiciais e a legalidade nos processos de impeachment e julgamentos políticos contra presidentes democraticamente eleitos. Finalmente, na quarta parte, alerta-se a Corte IDH sobre a importância de se especificar o alcance do artigo 23 da Convenção Americana de Direitos Humanos (CADH) em relação aos diferentes fenômenos que ocorrem nos Estados Partes da CADH. O objetivo do trabalho é oferecer à Corte IDH uma visão completa do conteúdo e de problemas concretos que surgem da solicitação de uma opinião consultiva tal como essa, formulada pela CIDH, como também um pronunciamento sobre o contexto jurídico e fático que rodeia este procedimento.This work concerns the request for an Advisory Opinion made by the Inter-American Commission on Human Rights (IACHR) on political judgments and impeachment, in order to encourage and broaden the debate on the subject. In this sense, the Núcleo Constitucionalismo e Democracia (Constitutionalism and Democracy Nucleus), which integrates the Centro de Estudos da Constituição (Center for Constitutional Studies – CCONS) of the Federal University of Paraná (UFPR) Law’s LL.M and Ph.D Program, and the Constitutional Law Department of the Externado University of Colombia, have joined together as amicus curiae and presented their view before the Inter-American Commission, aiming to collaborate, theoretically and practically, with the Inter-American System of Human Rights (IASHR). The first part of this report presents comments on the consultation formulated by the IACHR, including the rules and structure of the advisory procedure itself. The second part deals with the role and legitimacy of international courts and tribunals – specifically, the Inter-American Court of Human Rights (IACHR) – for the protection of democracy and political rights. The third part refers to the core object of the consultation – on judicial guarantees and legality in impeachment proceedings and political trials against democratically elected presidents. Finally, in the fourth part, the Inter-American Court is warned about the importance of specifying the scope of Article 23 of the American Convention on Human Rights (ACHR) in relation to the different phenomena occurring in the States that have ratified it. The objective of this work is to provide the Inter-American Court with a complete view of the content and concrete problems that arise from the request for an advisory opinion such as that formulated by the IACHR, as well as with a statement on the legal and factual context surrounding this procedure