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1.
J Am Assoc Lab Anim Sci ; 62(3): 267-273, 2023 05 01.
Article in English | MEDLINE | ID: mdl-37130700

ABSTRACT

Since 2015, the National Institutes of Health has called for its funded preclinical research to include both male and female subjects. However, much of the basic animal research that has studied heart rate and blood pressure in the past has used male rats. Male rats have been preferred for these studies to avoid the possible complicating effects of the female estrous cycle. The aim of the current study was to determine whether blood pressure and heart rates vary as a function of the estrous cycle phase of young normotensive Wistar-Kyoto (WKY) and Spontaneously Hypertensive (SHR) female rats. Blood pressure and heart rate were measured at the same time of day throughout the estrous cycle by using a noninvasive tail cuff sphygmomano- metric technique. As expected, 16-wk-old female SHR rats had higher blood pressure and heart rates than did age-matched female WKY rats. However, no significant differences in mean, systolic, or diastolic arterial blood pressure or heart rate were detected across the different stages of the estrous cycle in either strain of female rats. Consistent with previous reports, heart rates were higher and showed less variation in the hypertensive SHR female rats as compared with the normotensive WKY female rats. These results indicate that studies measuring blood pressure and heart rate can include young female SHR and WKY rats with no effect of estrous cycle stage.


Subject(s)
Hypertension , Rats , Male , Female , Animals , Blood Pressure , Rats, Inbred SHR , Rats, Inbred WKY , Heart Rate
2.
Sci Rep ; 7(1): 11862, 2017 09 19.
Article in English | MEDLINE | ID: mdl-28928412

ABSTRACT

Traceability of seafood has become crucial with market globalization and consumer's awareness. The present study used PCR-DGGE and 454 pyrosequencing to assess if bacterial communities fingerprint associated to seabass (Dicentrarchus labrax) skin mucus can be used to discriminate the geographic origin of fishes cultured in three semi-intensive fish farms. PCR-DGGE and pyrosequencing results were congruent and suggested that this molecular approach has the potential to trace fish farms with a spatial resolution <500 m. Pyrosequencing results provided a detailed insight into the bacterial community composition of seabass skin mucus and revealed the existence of a core of bacterial communities within family Pseudomonadaceae and Rhodobacteraceae. This approach also allowed to recognized key OTUs that are potentially relevant to discriminate the geographic origin of the fish being surveyed. Overall, the present study increased our knowledge on farmed seabass microbiome and demonstrated that specific and unique bacterial taxa can act as natural signatures that allow us to trace fish to its respective geographic origin. Our study provides valuable clues that should be more investigated in future studies as a way to fulfill current traceability needs in the global trade of seafood.


Subject(s)
Bacteria/genetics , Bass/microbiology , DNA Fingerprinting , DNA, Bacterial/genetics , DNA, Ribosomal/genetics , Microbiota/genetics , RNA, Ribosomal, 16S/genetics , Animals , Aquaculture/methods , Bass/growth & development
3.
Sci Rep ; 7(1): 3475, 2017 06 14.
Article in English | MEDLINE | ID: mdl-28615721

ABSTRACT

Understanding spatio-temporal variability of trace elements fingerprints (TEF) in bivalve shells is paramount to determine the discrimination power of this analytical approach and secure traceability along supply chains. Spatio-temporal variability of TEF was assessed in cockle (Cerastoderma edule) shells using inductively coupled plasma-mass spectrometry (ICP-MS). Four elemental ratios (Mg/Ca, Mn/Ca, Sr/Ca and Ba/Ca) were measured from the shells of specimens originating from eight different ecosystems along the Portuguese coast, as well as from four different areas, within one of them, over two consecutive years (2013 and 2014). TEF varied significantly in the shells of bivalves originating from the eight ecosystems surveyed in the present study. Linear discriminant function analyses assigned sampled cockles to each of the eight ecosystems with an average accuracy of 90%. Elemental ratios also displayed significant differences between the two consecutive years in the four areas monitored in the same ecosystem. Overall, while TEF displayed by cockle shells can be successfully used to trace their geographic origin, a periodical verification of TEF (>6 months and <1 year) is required to control for temporal variability whenever comparing specimens originating from the same area collected more than six months apart.


Subject(s)
Animal Shells/chemistry , Cardiidae/chemistry , Trace Elements/analysis , Analysis of Variance , Animals , Multivariate Analysis , Spatio-Temporal Analysis
4.
Environ Pollut ; 208(Pt B): 626-36, 2016 Jan.
Article in English | MEDLINE | ID: mdl-26552525

ABSTRACT

This study aimed to assess the effect of ultraviolet radiation (UVR) and chemical stress (triclosan-TCS; potassium dichromate-PD; prochloraz-PCZ) on bacterial communities of zebrafish (Danio rerio) embryos (ZEBC). Embryos were exposed to two UVR intensities and two chemical concentrations not causing mortality or any developmental effect (equivalent to the No-Observed-Effect Concentration-NOEC; NOEC diluted by 10-NOEC/10). Effects on ZEBC were evaluated using denaturing gradient gel electrophoresis (DGGE) and interpreted considering structure, richness and diversity. ZEBC were affected by both stressors even at concentrations/doses not affecting the host-organism (survival/development). Yet, some stress-tolerant bacterial groups were revealed. The structure of the ZEBC was always affected, mainly due to xenobiotic presence. Richness and diversity decreased after exposure to NOEC of PD. Interactive effects occurred for TCS and UVR. Aquatic microbiota imbalance might have repercussions for the host/aquatic system, particularly in a realistic scenario/climate change perspective therefore, future ecotoxicological models should consider xenobiotics interactions with UVR.


Subject(s)
Bacteria/drug effects , Bacteria/radiation effects , Embryo, Nonmammalian/microbiology , Stress, Physiological , Ultraviolet Rays , Water Pollutants, Chemical/toxicity , Zebrafish/embryology , Animals , Climate Change , Triclosan/toxicity , Zebrafish/microbiology
5.
Sci Rep ; 5: 11125, 2015 Jun 18.
Article in English | MEDLINE | ID: mdl-26084395

ABSTRACT

Geographic traceability of seafood is key for controlling its quality and safeguarding consumers' interest. The present study assessed if the fatty acid (FA) profile of the adductor muscle (AM) of fresh cockles (Cerastoderma edule) can be used to discriminate the origin of specimens collected in different bivalve capture/production areas legally defined within a coastal lagoon. Results suggest that this biochemical approach holds the potential to trace sampling locations with a spatial resolution <10 Km, even for areas with identical classification for bivalve production. Cockles further away from the inlet, i.e. in areas exposed to a higher saline variation, exhibited lower levels of saturated fatty acids, which are key for stabilizing the bilayer structure of cell membranes, and a higher percentage of polyunsaturated fatty acids, which enhance bilayer fluidity. Results suggest that the structural nature of the lipids present in the AM provides a stable fatty acid signature and holds potential for tracing the origin of bivalves to their capture/production areas.


Subject(s)
Cardiidae/physiology , Fatty Acids/metabolism , Muscle, Skeletal/physiology , Animals , Geography , Muscle Contraction , Portugal
6.
Trends Biotechnol ; 33(6): 331-6, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25865857

ABSTRACT

Market globalization and recurring food safety alerts have resulted in a growing consumer awareness of the need for food traceability. This is particularly relevant for seafood due to its perishable nature and importance as a key protein source for the population of the world. Here, we provide an overview of the current needs for seafood origin traceability, along with the limitations and challenges for its implementation. We focus on geochemical, biochemical, and molecular tools and how they should be optimized to be implemented globally and to address our societal needs. We suggest that seafood traceability is key to enforcing food safety regulations and fisheries control, combat fraud, and fulfill present and future expectations of conscientious producers, consumers, and authorities.


Subject(s)
Biotechnology/methods , Food Safety , Seafood/analysis , Certification , Humans , Seafood/standards
7.
PLoS One ; 9(7): e102187, 2014.
Article in English | MEDLINE | ID: mdl-25029191

ABSTRACT

Brazil nut, the Bertholletia excelsa seed, is one of the most important non-timber forest products in the Amazon Forest and the livelihoods of thousands of traditional Amazonian families depend on its commercialization. B. excelsa has been frequently cited as an indicator of anthropogenic forests and there is strong evidence that past human management has significantly contributed to its present distribution across the Amazon, suggesting that low levels of harvesting may play a positive role in B. excelsa recruitment. Here, we evaluate the effects of Brazil nut harvesting by the Kayapó Indigenous people of southeastern Amazonia on seedling recruitment in 20 B. excelsa groves subjected to different harvesting intensities, and investigated if management by harvesters influences patterns of B. excelsa distribution. The number of years of low-intensity Brazil nut harvesting by the Kayapó over the past two decades was positively related to B. excelsa seedling density in groves. One of the mechanisms behind the higher seedling density in harvested sites seems to be seed dispersal by harvesters along trails. The Kayapó also intentionally plant B. excelsa seeds and seedlings across their territories. Our results show not only that low-intensity Brazil nut harvesting by the Kayapó people does not reduce recruitment of seedlings, but that harvesting and/or associated activities conducted by traditional harvesters may benefit B. excelsa beyond grove borders. Our study supports the hypothesis that B. excelsa dispersal throughout the Amazon was, at least in part, influenced by indigenous groups, and strongly suggests that current human management contributes to the maintenance and formation of B. excelsa groves. We suggest that changes in Brazil nut management practices by traditional people to prevent harvesting impacts may be unnecessary and even counterproductive in many areas, and should be carefully evaluated before implementation.


Subject(s)
Bertholletia/physiology , Environment , Plant Dispersal , Population Groups , Conservation of Natural Resources , Humans , Seedlings/physiology , Seeds/physiology
8.
Ecol Appl ; 22(2): 722-34, 2012 Mar.
Article in English | MEDLINE | ID: mdl-22611867

ABSTRACT

Riparian habitats are important for the maintenance of regional biodiversity. Many studies have compared bird distributions between riparian and non-riparian habitats but have not established how wide riparian habitats used by birds are, as measured by distance from the nearest stream. We investigated the distribution of understory birds along gradients of distance from streams, soil clay content, and slope in a central Amazonian forest, by mist-netting birds three times in 45 plots. We used nonmetric multidimensional scaling (NMDS) to reduce the dimensionality of species quantitative (abundance) and qualitative (presence-absence) composition to one multivariate axis. Estimates of the width of riparian habitats as indicated by understory birds depended on the community attribute considered, measuring 90 m for species quantitative composition and 140 m for species qualitative composition. Species distributions were correlated with clay content but were independent of slope, while distance from streams was positively correlated with clay content but independent of slope. Clay content affects plant species composition, which in turn, may influence bird species composition. However, distribution patterns of birds in relation to distance from streams are consistent among studies carried out in many different temperate and tropical regions, indicating an effect of distance from streams itself. Protection of riparian habitats is one of the most widely used conservation strategies, and Brazilian environmental legislation mandates the protection of a 30 m wide strip of riparian vegetation on either side of small streams. We show that the protected strip should be much wider and recommend strategies to place other forms of land protection contiguous with riparian areas so that Brazilian environmental legislation better fulfills its role of protecting biodiversity associated with riparian habitats.


Subject(s)
Birds/physiology , Ecosystem , Rivers , Trees , Animals , Brazil , Conservation of Natural Resources/legislation & jurisprudence , Conservation of Natural Resources/methods , Demography , Environmental Monitoring/legislation & jurisprudence , Environmental Monitoring/methods
9.
Acta amaz ; 25(1)1995.
Article in Portuguese | LILACS-Express | LILACS, VETINDEX | ID: biblio-1454564

ABSTRACT

Samples of eleven fish species were collected during September and October of 1991 in the gold mining area of Cachoeira de Teotônio and in the control area Guajará-Mirim, along the Madeira River, (Rondônia, Brazil) and anaiized for total mercury by cold vapor atomic absorption spectrofotometry. Almost all fish predators from the gold mining area had mercury concentrations above the maximal level of 0.5 ug.g"1, permitted for human consumption by Brazilian Secretary of Health and the World Health Organization and much greater than those found in predatory fish species in the control area were all below this critical value (0.5 pg.g'X demonstrating the influence of anthropogenic contamination in the gold mining area. In both areas, non-predators fish species had lower mercury concentrations than predators fish species, indicating the effects of biomagnification of mercury in the food chain. Safety limits for fish consumption by the human populations in this gold mining area were estabilished considering the mercury levels encontred in fish and the critical intake rate associated with the signs of mercury poisoning. Pacu, could be consumed without restrictions, matrinchã, curimatã, mandi and tucunaré, could be consumed with moderation and large predatory fish species (mostly Siluriformes), could be consumed only sporadically. Some factors that could influence mercury contaminations in "ribeirinhos" are discussed.


A concentração de mercúrio total foi determinada em onze espécies de peixes coletados de setembro a outubro de 1991, na área de garimpo de ouro da Cachoeira de Tcotônio e da área considerada controle em Guajará-Mirim, ambas no rio Madeira, Estado de Rondônia. Utilizou-se, para a análise, a técnica de espectrofotometria de absorção atômica com gerador de vapor frio de Hg. Quase todos os peixes predadores da área de garimpo tiveram concentrações de mercúrio acima do nível critico de 0,5 pg.g"1 permitido para consumo humano pelo Ministério da Saúde do Brasil e Organização Mundial de Saúde, sendo bem maiores que as concentrações de mercúrio nas espécies predadoras da área controle, evidenciando a influência do garimpo de ouro na contaminação dos peixes por mercúrio. As espécies não-predadoras tiveram concentrações de mercúrio abaixo daquelas das espécies predadoras para as duas áreas, indicando o efeito da biomagnificação do mercúrio na cadeia alimentar. Procurou-se estabelecer limites para o consumo de peixes pelas populações humanas da área de garimpo estudada, calculando-se a taxa de ingestão necessária para se desenvolver os primeiros sintomas de contaminação mercurial. Concluiu-se que espécies como o pacu podem ser consumidas sem restrição, já os peixes como matrinchã, curimatã, mandi e tucunaré, deveriam ser consumidos com moderação e que a maioria dos peixes predadores (em geral Siluriformes), deveriam ser consumidos apenas esporadicamente. Discutem-se alguns fatores que poderiam estar interagindo no processo de contaminação por mercúrio dos ribeirinhos dessa área de garimpo.

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