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1.
An Acad Bras Cienc ; 92(2): e20180766, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32520217

RESUMO

Two dimensions of the ecological niche (diet and habitat) of a snake assemblage from an endemic rich area in east-central Argentina, the Sierras de Ventania mountain chain, were analyzed. Field data collection was performed in 15-week study periods between 2010 and 2014. Snakes were hand-captured using transect surveys. Field observations on diet were analyzed together with stomach content data from museum specimens. Our results supported the partitioning of the snake assemblage by both habitat use and diet into at least three functional groups: species restricted to microhabitats under rocks and with a diet composed exclusively of ants (Epictia australis); species found mostly in stream microhabitats and feeding mainly upon anurans (Erythrolamprus poecilogyrus and Lygophis elegantissimus); and species found mostly in grassland microhabitats, with specialized diets of terrestrial prey items (Philodryas patagoniensis and Bothrops alternatus). Consistent with previous work, diet was more important than habitat in explaining ecological niche partitioning of this snake assemblage. Our results showed that high overlap values of microhabitat use were compensated by low overlap values of the trophic niche dimension, thus matching the traditional complementary niches hypothesis.


Assuntos
Comportamento Alimentar/fisiologia , Conteúdo Gastrointestinal , Serpentes/fisiologia , Animais , Argentina , Estações do Ano , Serpentes/classificação
2.
Mar Pollut Bull ; 152: 110863, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32479271

RESUMO

We investigated differences in the feeding habits of the starspotted smooth-hound, Mustelus manazo, in Tokyo Bay between the mid-1990s (low stock size) and the late 2000s (high stock size). The frequency of M. manazo with empty stomachs increased from 5.9% in the mid-1990s to 16.1% in the late 2000s. A decrease in the relative weight of the stomach contents was evident from the mid-1990s to the late 2000s, especially in the small size classes, along with changes in the species composition in the stomach contents. Although crustaceans were the main constituents of the stomach contents, the proportion of crabs increased while those of shrimps and hermit crabs decreased. Changes in the feeding habits of M. manazo may be associated with shifts in the benthic community structure in Tokyo Bay.


Assuntos
Baías , Elasmobrânquios , Animais , Comportamento Alimentar , Conteúdo Gastrointestinal , Hábitos , Tóquio
3.
Bull Environ Contam Toxicol ; 104(5): 595-601, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32242255

RESUMO

Total mercury (THg) and selenium (TSe) levels were measured in stomach contents (SC) and twelve tissues of cutthroat trout (Oncorhynchus clarkii) occurring in three high-elevation lakes of Colorado, USA, inhabiting watersheds absent past and current mining activities. For 32 of 36 tissues, including muscle, mean THg wet weight (ww) concentrations were greater than in the diet (SC) for all sites, indicating biomagnification. Ranges of THg (µg/kg ww) for SC and stomach tissue (ST) were 1.23-73.54 and 14.55-61.35, respectively. Selenium concentrations in fish muscle were not greater than in the SC indicating a trophic transfer factor < 1.0. However, in several other tissues, mean Se dry weight (dw) levels were greater than in SC for all three lakes. Ranges of TSe for SC and ST were 166-7544 and 797-7523 (µg/kg dw), respectively. The muscle to egg/ovary ratio for Se averaged 2.30, 4.60, and 2.68 for the three populations. The variability of SC (planktonic vs. benthic) and differential distributions of THg and TSe in SC and organ-tissues generated questions focusing on the seasonal, physiological, and genetic drivers of these organometal(loid)s in subalpine trout.


Assuntos
Bioacumulação , Monitoramento Ambiental/métodos , Conteúdo Gastrointestinal/química , Mercúrio/metabolismo , Oncorhynchus/metabolismo , Selênio/metabolismo , Poluentes Químicos da Água/metabolismo , Animais , Colorado , Cadeia Alimentar , Lagos/química , Mercúrio/análise , Mineração , Plâncton/química , Selênio/análise , Poluentes Químicos da Água/análise
4.
Mar Pollut Bull ; 153: 110959, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32275522

RESUMO

This study aims to identify, classify, quantify the ingested microplastic by marine teleost fish, in order to analyze the relationship between microplastic and trophic guilds. Food items of 214 individuals of Opisthonema oglinum, Bagre marinus, Cathorops spixii, Sciades herzbergii, Chloroscombrus chrysurus, Conodon nobilis, Haemulopsis corvinaeformis were analyzed. The species were classified according to their trophic guilds (zoobenthivorous or opportunistic/omnivorous). All species ingested microplastic and contamination occurred independently of the trophic guild. Of the sampled fish, 55% were contaminated by microplastic. The most consumed categories were blue (28%) and transparent filaments (20%). Raman spectroscopy measurements detected that most sampled filament corresponds to blue synthetic fiber (polyester). This study can contribute by filling gaps in knowledge regarding sandy beach impacts, which are environments so highly threatened by human activities around the world and are neglected in terms of use and conservation plans.


Assuntos
Monitoramento Ambiental , Peixes , Microplásticos , Poluentes Químicos da Água , Animais , Brasil , Ingestão de Alimentos , Comportamento Alimentar , Conteúdo Gastrointestinal , Plásticos
5.
Curr Opin Anaesthesiol ; 33(3): 277-283, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32324656

RESUMO

PURPOSE OF REVIEW: This review focuses on the use of point-of-care ultrasound (PoCUS) in the obstetric context for airway management and assessment of aspiration risk, the placement of neuraxial blocks and the diagnosis and follow-up of cardiorespiratory dysfunction. RECENT FINDINGS: Gastric ultrasound is a useful aspiration risk assessment tool in pregnant patients. Total gastric fluid assessment models and specific cut-offs between high-risk and low-risk stomachs are presented. Airway assessment is useful to detect specific changes in pregnancy and to guide airway management. Handheld ultrasound devices with automated neuraxial landmark detection capabilities could facilitate needle placement in the future. Lung and cardiac ultrasonography is useful in the management of preeclampsia, pulmonary arterial hypertension and peripartum cardiomyopathy. SUMMARY: Owing to its noninvasiveness, ease of accessibility and lack of exposure to radiation, PoCUS plays an increasing and essential role in aspiration risk assessment, airway management, neuraxial anaesthesia and cardiorespiratory diagnosis and decision-making during pregnancy.


Assuntos
Manuseio das Vias Aéreas/métodos , Conteúdo Gastrointestinal/diagnóstico por imagem , Sistemas Automatizados de Assistência Junto ao Leito , Aspiração Respiratória/prevenção & controle , Ultrassonografia/métodos , Ecocardiografia/métodos , Feminino , Humanos , Gravidez , Medição de Risco/métodos , Estômago/diagnóstico por imagem
6.
Mar Pollut Bull ; 153: 110974, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32275532

RESUMO

Plastics pollution is ubiquitous. Microplastics (<5 mm in diameter) and mesoplastics (5-20 mm in diameter) are emerging as the most common plastic particulates found in the marine environment. In this study, the occurrence of microplastics and mesoplastics in the gastrointestinal tract (GI) of some commercially important fish collected from Chennai and Nagapattinam of Tamil Nadu, Southeast coast of Bay of Bengal was assessed. A new and improved alkaline digestion method, using alcoholic potassium hydroxide (KOH) was carried out to destroy the organic matter. Following this method, twenty plastic particulates were isolated from the GI tract of 17 individual fish. Fourier Transform Infrared Radiation analysis (FTIR) showed that polymers found in GI tracts were of Polyethylene, Polyamide and Polyester types. Given the dry fish is India's biggest market and popular delicacy, the presence of microplastics in the fish gut is a potential serious human health concern, as they are directly consumed.


Assuntos
Monitoramento Ambiental , Peixes , Conteúdo Gastrointestinal/química , Microplásticos/análise , Poluentes Químicos da Água/análise , Animais , Baías , Índia , Plásticos , Inquéritos e Questionários
8.
Int J Syst Evol Microbiol ; 70(4): 2318-2324, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32195648

RESUMO

Four novel bacterial strains, designated Z294T, Z311, Z443T and Z446, were isolated from the intestinal contents of plateau pika (Ochotona curzoniae) on the Qinghai-Tibet Plateau of China. Cells were Gram-stain-positive, catalase-positive, oxidase-negative, aerobic, non-motile and short-rod shaped. Phylogenetic analyses based on 16S rRNA gene sequences indicated that the four isolates belong to the genus Georgenia, but clearly separate from the currently recognized species. Both type strains (Z294T and Z443T) shared low 16S rRNA gene sequence similarity, digital DNA-DNA hybridization relatedness and average nucleotide identity values with Georginia satyanarayanai NBRC 107612T, G. subflava JCM 19765T, G. ruanii JCM 15130T and G. thermotolerans DSM 21501T and against each other. The genomic DNA G+C contents of strains Z294T and Z443T were 73.3 and 70 %, respectively. The major cellular fatty acids of strain Z294T were anteiso-C15 : 0, anteiso-C15 : 1 A and C16 : 0, in contrast to anteiso-C15 : 0 and anteiso-C15 : 1 A for strain Z443T. Both type strains (Z294T and Z443T) shared the following common features: glucose, rhamnose and ribose as cell-wall sugars; MK-8(H4) as major menaquinone; alanine, glutamic acid and lysine as cell-wall amino acids; and diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol, phosphatidylinositol mannoside and one unidentified phosphoglycolipid as polar lipids. Comparing the phenotypic and phylogenetic features among the four strains and their related organisms, strains Z294T and Z443T represent two novel species within the genus Georgenia, for which the names Georgenia wutianyii sp. nov. (type strain Z294T=CGMCC 1.16428T=DSM 106344T) and Georgenia yuyongxinii sp. nov. (type strain Z443T=CGMCC 1.16435T=DSM 106174T) are proposed.


Assuntos
Actinobacteria/classificação , Conteúdo Gastrointestinal/microbiologia , Lagomorpha/microbiologia , Filogenia , Actinobacteria/isolamento & purificação , Animais , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Hibridização de Ácido Nucleico , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Tibet , Vitamina K 2/análogos & derivados , Vitamina K 2/química
9.
PLoS Negl Trop Dis ; 14(3): e0008077, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32214313

RESUMO

BACKGROUND: Phlebotomus (Larroussius) perniciosus and Canis familiaris are respectively the only confirmed vector and reservoir for the transmission of Leishmania (L.) infantum MON-1 in Tunisia. However, the vector and reservoir hosts of the two other zymodemes, MON-24 and MON-80, are still unknown. The aim of this study was to analyze the L. infantum life cycle in a Tunisian leishmaniasis focus. For this purpose, we have focused on: i) the detection, quantification and identification of Leishmania among this sand fly population, and ii) the analysis of the blood meal preferences of Larroussius (Lar.) subgenus sand flies to identify the potential reservoirs. METHODOLOGY AND FINDINGS: A total of 3,831 sand flies were collected in seven locations from the center of Tunisia affected by human visceral leishmaniasis. The collected sand flies belonged to two genus Phlebotomus (Ph.) (five species) and Sergentomyia (four species). From the collected 1,029 Lar. subgenus female sand flies, 8.26% was positive to Leishmania by ITS1 nested PCR. Three Leishmania spp. were identified: L. infantum 28% (24/85), L. killicki 13% (11/85), and L. major 22% (19/85). To identify the blood meal sources in Ph. Lar. subgenus sand flies, engorged females were analyzed by PCR-sequencing targeting the vertebrate cytochrome b gene. Among the 177 analyzed blood-fed females, 169 samples were positive. Sequencing results showed seven blood sources: cattle, human, sheep, chicken, goat, donkey, and turkey. In addition, mixed blood meals were detected in twelve cases. Leishmania DNA was found in 21 engorged females, with a wide range of blood meal sources: cattle, chicken, goat, chicken/cattle, chicken/sheep, chicken/turkey and human/cattle. The parasite load was quantified in fed and unfed infected sand flies using a real time PCR targeting kinetoplast DNA. The average parasite load was 1,174 parasites/reaction and 90 parasites/reaction in unfed and fed flies, respectively. CONCLUSION: Our results support the role of Ph. longicuspis, Ph. perfiliewi, and Ph. perniciosus in L. infantum transmission. Furthermore, these species could be involved in L. major and L. killicki life cycles. The combination of the parasite detection and the blood meal analysis in this study highlights the incrimination of the identified vertebrate in Leishmania transmission. In addition, we quantify for the first time the parasite load in naturally infected sand flies caught in Tunisia. These findings are relevant for a better understanding of L. infantum transmission cycle in the country. Further investigations and control measures are needed to manage L. infantum transmission and its spreading.


Assuntos
DNA/análise , Comportamento Alimentar , Conteúdo Gastrointestinal/química , Conteúdo Gastrointestinal/parasitologia , Especificidade de Hospedeiro , Leishmania infantum/isolamento & purificação , Phlebotomus/fisiologia , Animais , DNA/genética , Impressões Digitais de DNA , DNA Espaçador Ribossômico/genética , Transmissão de Doença Infecciosa , Feminino , Humanos , Leishmania infantum/genética , Masculino , Phlebotomus/parasitologia , Reação em Cadeia da Polimerase , Análise de Sequência de DNA , Tunísia
10.
Environ Pollut ; 261: 114194, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32113106

RESUMO

As in the rest of the world, plastics are the most dominant marine litter category in Moroccan Atlantic waters. This work aims to identify the presence of microplastics in the stomach contents of three small pelagic species of the Central zone of the Atlantic, located between Cape Cantin (33°N) and Cape Boujdor (26°N): Scomber spp., Truchurus truchurus and Sardina pilchardus; Also, to map the spatial distribution of the investigated species. A total of 251 individuals were examined, composed by 118 Scomber spp, 82 Sardina pilchardus and 51 Trachurus trachurus. The characterization of microplastics ingested by those species was identified by FTIR. The results showed the presence of three polymers: Polyamide (PA), Acrylic (PC) and Polystyrene (PS), in 26% of the individuals studied. The presence of polymers was accumulated in Atlantic horse mackerel (Truchurus truchurus) with 30%, then in mackerels (Scomber spp.) with 27%, and European pilchardus (Sardina pilchardus) (9%). Fish containing microplastics in their stomachs are concentrated, mainly in the northern part of the study area. This zone has significant artisanal fishing activity and large rivers that can be source of microplastics.


Assuntos
Ingestão de Alimentos , Monitoramento Ambiental , Microplásticos , Perciformes , Animais , Oceano Atlântico , Conteúdo Gastrointestinal , Microplásticos/análise , Microplásticos/metabolismo , Marrocos , Perciformes/fisiologia , Poluentes Químicos da Água/análise
11.
Oecologia ; 192(4): 1111-1126, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32179976

RESUMO

Calculation of dietary niche characteristics using stable isotopes has become a popular approach to understand the functional role of taxa across food webs. An underlying assumption of this approach is that stable isotopes accurately reflect the dietary breadth of a species over a temporal duration defined by tissue-specific isotopic turnover rates. In theory, dietary niche estimates derived from fast turnover rate tissues (e.g., blood plasma and liver) may augment stomach content-derived estimates more agreeably than slower turnover rate tissues (e.g., muscle or fin). We tested this hypothesis by comparing commonly used dietary niche estimates derived from stomach contents (nicheSCA: Levins', Shannon-Wiener's, and Smith's), with those estimated using stable isotopes [nicheSIA: standard ellipse area (SEA), convex hull total area (TA), theta (θ), and ellipse eccentricity (E)] of liver and muscle tissue. Model species were three large-bodied sharks: white (Carcharodon carcharias), dusky (Carcharhinus obscurus), and scalloped hammerhead (Sphyrna lewini). Within-technique comparisons for nicheSCA and nicheSIA metrics (i.e., SEA vs. TA) were often correlated; however, we did not observe any statistically significant correlations between nicheSCA and liver/muscle tissue nicheSIA (i.e., Levins' vs. SEA). We conclude that nicheSCA and nicheSIA do not provide comparable estimates of dietary niche, at least for the three predator species examined. This fundamental discrepancy highlights technique-specific limitations to estimating organismal dietary niche and identifies a need for the use of clearly defined niche metrics, i.e., the standardized use and reporting of the term isotopic niche as proposed by Newsome et al. (Front Ecol Environ 5:429-436, 2007). Finally, further investigation into the factors underpinning nicheSIA is required to better contextualize this popular ecological metric when compared to nicheSCA.


Assuntos
Conteúdo Gastrointestinal , Tubarões , Animais , Isótopos de Carbono , Cadeia Alimentar , Isótopos de Nitrogênio
12.
Int J Syst Evol Microbiol ; 70(4): 2233-2238, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32100695

RESUMO

Two Gram-staining-positive, catalase-positive, oxidase-negative, aerobic, non-motile, irregular rod-shaped bacterial strains (Z350T and Z527) were isolated from intestinal contents of plateau pika (Ochotona curzoniae) from the Qinghai-Tibet Plateau, PR China. Results of phylogenetic analyses based on 16S rRNA gene sequences indicated that strain Z350T belongs to the genus Mumia (family Nocardioidaceae) but clearly differs from the currently recognized species Mumia xiangluensis DSM 101040T (98.4 % similarity) and Mumia flava DSM 27763T (97.4 %). Strain Z350T had a DNA G+C content of 70.7 mol% and shared 80.4 and 76.7 % average nucleotide identity values and 23.4 and 20.6 % in silico DNA-DNA hybridization relatedness with M. xiangluensis DSM 101040T and M. flava DSM 27763T, respectively. Further phylogenetic analyses based on 497 core genes indicated that our isolates were members of the genus Mumia but separated from all existing genera within the family Nocardioidaceae. The major cellular fatty acids were C18 : 1 ω9c and 10-methyl C18 : 0. The cell wall contained ll-diaminopimelic acid as the diamino acid, and rhamnose, ribose and glucose as whole cell-wall sugars. MK-9(H4) was detected as the major menaquinone. Polar lipids present were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol, phosphatidylinositol mannoside and one unidentified phospholipid. Based on distinct differences in the genotypic and phenotypic data from the two Mumia species, a novel species, Mumia zhuanghuii sp. nov., is proposed. The type strain is Z350T (=CGMCC 4.7464T=DSM 106288T).


Assuntos
Actinobacteria/classificação , Conteúdo Gastrointestinal/microbiologia , Lagomorpha/microbiologia , Filogenia , Actinobacteria/isolamento & purificação , Animais , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácido Diaminopimélico/química , Ácidos Graxos/química , Hibridização de Ácido Nucleico , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Tibet , Vitamina K 2/análogos & derivados , Vitamina K 2/química
13.
Int J Syst Evol Microbiol ; 70(4): 2247-2253, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32100704

RESUMO

Two aerobic, Gram-stain-positive, catalase-positive, non-motile and rod-shaped bacterial strains, designated MF30-AT and MF845, were isolated from the intestinal contents of plateau pika collected from the Qinghai-Tibet Plateau. Optimal growth of these two strains was observed under aerobic conditions at pH 7.0 and 28 °C. The 16S rRNA gene sequences of the isolates had highest similarities of 98.5 and 98.4 % to Agromyces fucosus, respectively. In the 16S rRNA gene and polygenetic trees, strains MF30-AT and MF845 were clearly distinct from other species. The two strains could not produce acid from arbutin, d-fructose, D-sucrose, glycogen, salicin or starch. Production of ß-glucosidase by these strains was negative. The major fatty acids of these strains were anteiso-C15 : 0, anteiso-C17 : 0 and iso-C16 : 0. Strain MF30-AT contained galactose, rhamnose and ribose as cell wall sugars and MK-12 and MK-11 as predominant menaquinones. The major polar lipids in strain MF30-AT were diphosphatidylglycerol, phosphatidylglycerol and a glycolipid, while the peptidoglycan contained alanine, glutamic acid, glycine and 2,4-diaminobutyric acid. The G+C contents of the DNA of strains MF30-AT and MF845 were 69.8 mol% and 69.7 mol%, respectively. The average nucleotide identity and digital DNA-DNA relatedness values of the two strains with all available genomes of the genus Agromyces were far below the respective thresholds of 95 and 70 %, respectively. All genotypic and phenotypic data indicated that strains MF30-AT and MF845 should be classified as novel members of the genus Agromyces, for which the name Agromyces badenianii sp. nov. is proposed. The type strain is MF30-AT (=CGMCC 1.16469T=DSM 106183T).


Assuntos
Actinobacteria/classificação , Conteúdo Gastrointestinal/microbiologia , Lagomorpha/microbiologia , Filogenia , Actinobacteria/isolamento & purificação , Animais , Técnicas de Tipagem Bacteriana , Composição de Bases , Parede Celular/química , DNA Bacteriano/genética , Ácidos Graxos/química , Glicolipídeos/química , Hibridização de Ácido Nucleico , Peptidoglicano/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Tibet , Vitamina K 2/química
14.
J Dairy Sci ; 103(4): 3349-3362, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32008786

RESUMO

Crossbreeding is a strategy to counter the declining fertility, resilience, and longevity of purebred Holstein (Ho) cows. However, little is known of the effects of long-term systematic rotational crossbreeding on milk technological properties and cheese yield (CY). In this study, we compared the individual milk composition, milk coagulation properties (MCP), and CY of 468 purebred Ho and 648 crossbred (CR) cows obtained from two 3-breed rotational crossbreeding systems using Viking Red (VR), Montbéliarde (Mo), and Ho sires over 4 generations. Individual milk samples were collected once from 1,116 primiparous and multiparous cows kept in 2 dairy herds, raised for the production of Grana Padano (high milk yield, total mixed ration based on corn silage) and Parmigiano Reggiano (moderate milk yield, only dry feeds) cheeses. In both herds, a 3-breed rotational mating system was used in which Ho cows were first inseminated with VR, whereas Mo and Ho semen was used in the subsequent generations. In one herd, the sequence Mo-VR-Ho was also used. Individual milk samples were analyzed for milk composition, single-point MCP, and parameters for modeling curd firming over time, whereas CY and milk nutrient recovery in the curd were assessed through a laboratory cheese-making procedure. Compared with Ho, CR cows produced 5.8% less milk, which had comparable fat but greater protein and casein contents and lower lactose contents and somatic cell scores. Milk from CR cows tended to reach a curd firmness of 20 mm more quickly and exhibited greater curd firmness at 45 and 60 min from rennet addition. Holstein and CR cows yielded milk with similar CY and recovery in the curd traits. The milk fat content, somatic cell scores, curd firmness traits, and CY of CR cows relative to the Ho cows differed in the 2 herds, and the favorable effects on the CR cows were more evident in the herd with the greatest milk yield and the worst MCP traits. Crossbred cows of the 4 generations performed similarly, with the exception of the better MCP of the milk from first-generation CR cows. The 2 rotational systems using different sire-breed sequences also performed similarly. In summary, both rotational crossbreeding programs exhibited some advantage over the Ho purebred breeding system in terms of milk composition and MCP but not CY. Future research is needed to investigate the interactions between crossbreeding schemes and dairy systems.


Assuntos
Bovinos/fisiologia , Queijo , Hibridização Genética , Leite/química , Animais , Feminino , Fertilidade , Conteúdo Gastrointestinal , Lactação , Masculino , Paridade , Fenótipo , Gravidez , Silagem , Zea mays
15.
Mar Pollut Bull ; 151: 110827, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32056619

RESUMO

This study investigates the frequency of microplastic (MP) ingestion and the relationship between microplastics in the guts of two commercial fish species in Iceland (cod; Gadus morhua and saithe; Pollachius virens) and the weight, length, gut fullness, and condition index (CI) of the fish. MPs were found in 20.5% of the cod (n = 39) and 17.4% of the saithe (n = 46). There was no significant correlation between gut fullness nor CI and findings of MPs, indicating that, especially in large individuals, MPs are not retained to a large extent, and if so, the CI is most likely not affected. A difference was found in fish length between fish containing plastic and fish without plastics. Further studies such as this must be conducted in all water ecosystems if we are to fully understand the impact that MP's are having at the individual, population, species, and ecosystem levels.


Assuntos
Monitoramento Ambiental , Peixes , Conteúdo Gastrointestinal , Plásticos , Poluentes Químicos da Água , Animais , Tamanho Corporal , Ecossistema , Islândia , Microplásticos
16.
Mar Pollut Bull ; 151: 110858, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32056640

RESUMO

This review quantifies plastic interaction in marine biota. Firstly, entanglement and ingestion records for all marine birds, mammals, turtles, fish, and invertebrate species, are summarized from 747 studies. Marine debris affected 914 species through entanglement and/or ingestion. Ingestion was recorded for 701 species, entanglement was documented for 354 species. Secondly, the frequency of occurrence of ingestion per species (Sp-%FO) was extracted for marine birds, mammals and turtles. Thirdly, for seabird species, average numbers of plastics ingested per individual were determined. Highest Sp-%FO and average number of plastics were found in tubenosed seabirds with 41% of all birds analysed having plastics, on average 9.9 particles per bird. The Sp-%FO and average number of ingested particles is lower for most other species. However, for certain species, ingestion rates of litter are reason for serious concern. Standardized methods are crucial for future studies, to generate datasets that allow higher level ecosystem analyses.


Assuntos
Monitoramento Ambiental , Resíduos , Poluentes Químicos da Água , Animais , Exposição Dietética/estatística & dados numéricos , Ingestão de Alimentos , Ecossistema , Conteúdo Gastrointestinal , Plásticos
17.
Mar Pollut Bull ; 151: 110795, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32056590

RESUMO

We exposed juvenile intertidal fish to different amounts of Poly(styrene-co-divinylbenzene) microplastics in their diet. We fed ten individuals with pellets containing 0.01 g, another ten fish with pellets containing 0.1 g of PS, and ten fish without plastic as control. After 45 days of treatment, the whole intestine was removed, and the histological evaluation started immediately. We evaluated inflammation due to leukocyte infiltration (Lk), circulatory disorders like Hypermeia (Hyp), and regressive changes in the intestinal tissue, assessing Crypt cell loss (Ccl) and Villi cell loss (Vcl). The severity of the lesions increased according to the microplastic concentration. In the fish group feeding on microplastics, we found that leukocyte infiltration and hyperemia were more severe in the higher exposure group compared to the lower exposure; and crypt cell loss and villi cell loss increased significantly due to Poly(styrene-co-divinylbenzene) microplastic physical abrasion.


Assuntos
Peixes , Conteúdo Gastrointestinal , Microplásticos , Poluentes Químicos da Água , Animais , Monitoramento Ambiental , Intestinos , Plásticos
18.
Aquat Toxicol ; 221: 105427, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32044545

RESUMO

Local population frequently consumes moray eels and dusky groupers from the Canary Islands. These species are top predators and the interactions between them include predation but also, in some cases, collaborative hunting. These fish are well known to cause ciguatera (CFP) outbreaks in several marine areas such as Japan, Hawaii, French Polynesia and Caribe. Groupers have been involved in CFP events in the Canary Islands, however, moray eels have not yet been well studied in this regard. The present research seeks to describe the finding of a black moray in the stomach of a positive dusky grouper during its necropsy, and to clarify the implication of groupers and moray eels in the food webs, accumulating CTXs in the Canarian environment. The study also updates statistics on the presence of toxic groupers in this archipelago. For these purposes, 248 grouper samples from the CFP official control in the Canary Islands (2018-2019) were analysed and 36 moray eels (5 species) were collected under the EuroCigua project and one was obtained during a dusky grouper necropsy. All samples were analysed with the Neuro-2a cell-based assay (CBA) to evidence CTX-like toxicity. Regarding the necropsied grouper and the moray eel found in its stomach content, the LCMS/MS method allowed the identification and quantification of CCTX1 in both fish at similar levels while none of the P-CTXs for which standards were available were detected. Among groupers, 25.4 % displayed CTX-like toxicity with differences between islands. For moray eels 38.9 % showed toxicity, involving 4 species. Black moray exhibited a high proportion of positives (9/12) and a positive correlation was found between CTX-like toxicity quantification and the black moray weight. Regarding the grouper, and the moray eel found in its stomach, the LCMS/MS method allowed the identification and quantification of C-CTX1 in both fish at similar levels. This found suggests a trophic interaction between these species and their role in maintaining CTXs in the Canary waters where local population commonly demand those species for consumption. The island of El Hierro stands out above all the other Canary Islands with the concerning percentage of positive grouper samples and the high CTX toxicity levels obtained in moray eel specimens analysed in this marine area. This is the first report of CTX-like toxicity in flesh of moray eels fished in the Canary archipelago and the confirmation of the presence of C-CTX1 by LCMS/MS in a black moray from this marine area.


Assuntos
Ciguatoxinas/análise , Enguias/metabolismo , Monitoramento Ambiental/métodos , Poluentes Químicos da Água/análise , Animais , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Cromatografia Líquida , Intoxicação por Ciguatera/epidemiologia , Intoxicação por Ciguatera/etiologia , Ciguatoxinas/toxicidade , Cadeia Alimentar , Contaminação de Alimentos/análise , Conteúdo Gastrointestinal/química , Músculos/química , Alimentos Marinhos/análise , Espanha , Poluentes Químicos da Água/toxicidade
19.
J Fish Biol ; 96(3): 681-692, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31970772

RESUMO

Life history strategies and potential marine niche use of Arctic charr Salvelinus alpinus (n = 237, 84-652 mm, total body length, LT ) were determined during the ice-free season (2012) at three different watercourses in south-western Greenland. All Arctic charr were collected from freshwater habitats. Based on stable isotopes of δ34 S, the Arctic charr were categorized as either marine- or freshwater-dependent feeders. The use of time-integrated trophic tracers (stable isotopes of δ13 C, δ15 N, δ34 S) suggested that several trophic groups of Arctic charr operate alongside within each fjord system. The groups suggested were one group that specialized in the marine habitat, in addition to two freshwater resident morphs (small-sized resident and/or large-growing cannibalistic individuals). Stomach contents consisted entirely of freshwater and terrestrial prey (i.e., insects), indicating that marine-dependent feeders also fed in freshwater habitats after return from their marine migration. Growth and maturity patterns further supported variable life history strategies within each watercourse. The life history strategy patterns and marine trophic niche use were consistent across the watercourses along several hundred kilometres of coastline. This study represents the first ecological baseline for partially anadromous populations of Greenland Arctic charr.


Assuntos
Dieta , Ecossistema , Truta/fisiologia , Animais , Organismos Aquáticos/metabolismo , Canibalismo , Água Doce , Conteúdo Gastrointestinal , Groenlândia , Estado Nutricional , Estações do Ano , Isótopos de Enxofre/análise , Truta/crescimento & desenvolvimento
20.
Mar Environ Res ; 155: 104876, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31965976

RESUMO

Plastics are widely diffused in the oceans and their ingestion by marine organisms is raising concern for potentially adverse effects. The risk of harmful interactions with marine plastic pollution depends on the biology of the species as well as the distribution and abundance of the different plastic types. The aim of this study was to assess the occurrence of plastic ingestion by the small-spotted catshark (Scyliorhinus canicula), one of the most abundant elasmobranchs in the Mediterranean Sea. The expression levels of genes indicative of total immune system function were analyzed to gather preliminary data for further investigation of any potential correlations between plastic presence and immune activation. One hundred catsharks were collected during the Spring 2018 in two geographic locations in the southern region of the central Mediterranean Sea: 1) near Mazara del Vallo, SW Sicily and 2) near Lampedusa island, Italy's southernmost. Standard measurements were recorded for each specimen and its organs and sex was determined. The gastrointestinal tract (GIT) was preserved for plastic detection and identification. Where present, plastics (macro- and micro-) were characterized in terms of size, shape and polymer typology through microscopy and µ-Raman spectroscopy. Spleen from a subset of thirty samples was preserved for RNA extraction, then used to quantify by real time PCR the transcripts of T cell receptor beta (TCRB), T cell receptor delta (TCRD) and IgM genes. The results indicated that ingestion of plastic is widespread, with microplastics (MP, from 1 µm to <1 mm) abundantly present in nearly all samples and macroplasticplastic (MaP, > 1 cm) in approximately 18% of the specimens collected. A significant increase in the expression of TCRB, TCRD and IgM was observed in the spleen of MaP + specimens from Mazara del Vallo waters, in parallel with 67% increase in liver weight. While the presence of MP alone is not enough to induce a strong activation of the immunity, some type of plastics falling into the MaP category may be more toxic than others and crucial in the activation of the immune response. The results of this study represent a first evidence that plastic pollution represents an emerging threat to S. canicula, the Mediterranean food web and human consumers.


Assuntos
Plásticos/efeitos adversos , Tubarões , Poluentes Químicos da Água , Animais , Ingestão de Alimentos , Monitoramento Ambiental , Conteúdo Gastrointestinal , Imunoglobulina M , Fígado , Mar Mediterrâneo , Receptores de Antígenos de Linfócitos T , Sicília , Baço
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