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1.
Folia Parasitol (Praha) ; 702023 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-36722286

RESUMO

We provide the first ultrastructural evidence of the secretion of extracellular vesicles (EVs) across all parasitic stages of the tapeworm Schistocephalus solidus (Müller, 1776) (Cestoda: Diphyllobothriidea) using a laboratory life cycle model. We confirmed the presence of EV-like bodies in all stages examined, including the hexacanth, procercoids in the copepod, Macrocyclops albidus (Jurine, 1820), plerocercoids from the body cavity of the three-spined stickleback, Gasterosteus aculeatus Linnaeus, and adults cultivated in artificial medium. In addition, we provide description of novel tegumental structures potentially involved in EV biogenesis and the presence of unique elongated EVs similar to those previously described only in Fasciola hepatica Linnaeus, 1758 (Trematoda), Hymenolepis diminuta (Rudolphi, 1819) (Cestoda), and Trypanosoma brucei Plimmer et Bradford, 1899 (Kinetoplastida).


Assuntos
Cestoides , Infecções por Cestoides , Copépodes , Vesículas Extracelulares , Smegmamorpha , Animais , Infecções por Cestoides/veterinária
2.
Am Nat ; 201(2): 175-199, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36724467

RESUMO

AbstractPopulations are subjected to diverse environmental conditions that affect fitness and induce evolutionary or plastic responses, resulting in phenotypic divergence. Some authors contend that such divergence is concentrated along a single major axis of trait covariance even if that axis does not lead populations directly toward a fitness optimum. Other authors argue that divergence can occur readily along many phenotype axes at the same time. We use populations of threespine stickleback (Gasterosteus aculeatus) from 14 lakes with contrasting ecological conditions to find some resolution along the continuum between these two extremes. Unlike many previous studies, we included several functional suites of traits (defensive, swimming, trophic) potentially subject to different sources of selection. We find that populations exhibit dimensionality of divergence that is high enough to preclude a history of constraint along a single axis-both for divergence in multivariate mean trait values and for the structure of trait covariances. Dimensionality varied among trait suites and were strongly influenced by the inclusion of specific traits, and integration of trait suites varied between populations. We leverage this variation into new insights about the process of divergence and suggest that similar analyses could increase understanding of other adaptive radiations.


Assuntos
Smegmamorpha , Animais , Smegmamorpha/genética , Evolução Biológica , Fenótipo , Lagos
3.
Proc Natl Acad Sci U S A ; 120(6): e2207739120, 2023 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-36716378

RESUMO

Interactions between humans and nature have profound consequences, which rarely are mutually beneficial. Further, behavioral and environmental changes can turn human-wildlife cooperative interactions into conflicts, threatening their continued existence. By tracking fine-scale behavioral interactions between artisanal fishers and wild dolphins targeting migratory mullets, we reveal that foraging synchrony is key to benefiting both predators. Dolphins herd mullet schools toward the coast, increasing prey availability within the reach of the net-casting fishers, who gain higher foraging success-but only when matching the casting behavior with the dolphins' foraging cues. In turn, when dolphins approach the fishers' nets closely and cue fishers in, they dive for longer and modify their active foraging echolocation to match the time it takes for nets to sink and close over mullets-but only when fishers respond to their foraging cues appropriately. Using long-term demographic surveys, we show that cooperative foraging generates socioeconomic benefits for net-casting fishers and ca. 13% survival benefits for cooperative dolphins by minimizing spatial overlap with bycatch-prone fisheries. However, recent declines in mullet availability are threatening these short- and long-term benefits by reducing the foraging success of net-casting fishers and increasing the exposure of dolphins to bycatch in the alternative fisheries. Using a numerical model parametrized with our empirical data, we predict that environmental and behavioral changes are pushing this traditional human-dolphin cooperation toward extinction. We propose two possible conservation actions targeting fishers' behavior that could prevent the erosion of this century-old fishery, thereby safeguarding one of the last remaining cases of human-wildlife cooperation.


Assuntos
Golfinhos , Smegmamorpha , Animais , Humanos , Conservação dos Recursos Naturais , Simbiose , Animais Selvagens , Pesqueiros
4.
Evolution ; 77(1): 13-25, 2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36622211

RESUMO

Lineages with independent evolutionary histories often differ in both their morphology and diet. Experimental work has improved our understanding of the links between the biomechanics of morphological traits and foraging performance (trait utility). However, because the expression of foraging-relevant traits and their utility can be highly context-specific, it is often unclear how dietary divergence arises from evolved phenotypic differences. Here, we explore the phenotypic causes of dietary divergence between two genetically and phenotypically divergent lineages of threespine stickleback (Gasterosteus aculeatus) with independent evolutionary histories of freshwater colonization and adaptation. First, using individuals from a line-cross breeding design, we conducted 150 common-garden foraging trials with a community of multiple prey species and performed morphological and behavioral analyses to test for prey-specific trait utility. Second, we tested if the traits that explain variation in foraging performance among all individuals could also explain the dietary divergence between the lineages. Overall, we found evidence for the utility of several foraging traits, but these traits did not explain the observed dietary divergence between the lineages in a common garden. This work suggests that evolved dietary divergence results not only from differences in morphology but also from divergence in behaviors that underlie prey capture success in species-rich prey communities.


Assuntos
Smegmamorpha , Humanos , Animais , Smegmamorpha/anatomia & histologia , Evolução Biológica , Fenótipo , Adaptação Fisiológica , Dieta
5.
Evolution ; 77(1): 110-122, 2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36622692

RESUMO

Recent studies have shown that the repeated evolution of similar phenotypes in response to similar ecological conditions (here "parallel evolution") often occurs through mutations in the same genes. However, many previous studies have focused on known candidate genes in a limited number of systems. Thus, the question of how often parallel phenotypic evolution is due to parallel genetic changes remains open. Here, we used quantitative trait locus (QTL) mapping in F2 intercrosses between lake and stream threespine stickleback (Gasterosteus aculeatus) from four independent watersheds on Vancouver Island, Canada to determine whether the same QTL underlie divergence in the same phenotypes across, between, and within watersheds. We find few parallel QTL, even in independent crosses from the same watershed or for phenotypes that have diverged in parallel. These findings suggest that different mutations can lead to similar phenotypes. The low genetic repeatability observed in these lake-stream systems contrasts with the higher genetic repeatability observed in other stickleback systems. We speculate that differences in evolutionary history, gene flow, and/or the strength and direction of selection might explain these differences in genetic parallelism and emphasize that more work is needed to move beyond documenting genetic parallelism to identifying the underlying causes.


Assuntos
Smegmamorpha , Animais , Smegmamorpha/genética , Rios , Lagos , Fenótipo , Deriva Genética
6.
Evolution ; 77(1): 239-253, 2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36622731

RESUMO

Gaining the ability to predict population responses to climate change is a pressing concern. Using a "natural experiment," we show that testing for divergent evolution in wild populations from contrasting thermal environments provides a powerful approach, and likely an enhanced predictive power for responses to climate change. Specifically, we used a unique study system in Iceland, where freshwater populations of threespine sticklebacks (Gasterosteus aculeatus) are found in waters warmed by geothermal activity, adjacent to populations in ambient-temperature water. We focused on morphological traits across six pairs from warm and cold habitats. We found that fish from warm habitats tended to have a deeper mid-body, a subterminally orientated jaw, steeper craniofacial profile, and deeper caudal region relative to fish from cold habitats. Our common garden experiment showed that most of these differences were heritable. Population age did not appear to influence the magnitude or type of thermal divergence, but similar types of divergence between thermal habitats were more prevalent across allopatric than sympatric population pairs. These findings suggest that morphological divergence in response to thermal habitat, despite being relatively complex and multivariate, are predictable to a degree. Our data also suggest that the potential for migration of individuals between different thermal habitats may enhance nonparallel evolution and reduce our ability to predict responses to climate change.


Assuntos
Ecossistema , Smegmamorpha , Animais , Água Doce , Fenótipo , Smegmamorpha/fisiologia
7.
Theriogenology ; 198: 317-326, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36638591

RESUMO

Wild adult females of a low trophic omnivore teleost species, the flathead grey mullet (Mugil cephalus), caught in the western Mediterranean were sampled. The lipid and fatty acid composition of ovaries, liver, muscle, and peritoneal fat were analysed at previtellogenesis, early-vitellogenesis -first observed at mid-summer (early August)-, late-vitellogenesis, and the post-spawning period -from mid-September to mid-October-. During ovarian development, the lipid content of muscle was low and constant (3.85%-4.92%), indicating that the muscle was not used to store lipids for gonadal growth. Although constant, lipid content in the liver was higher (18.46%-22.62%) than in the muscle, and HSI% increased during gonad development, suggesting a dynamism in the mobilization of the hepatic lipids. Total lipids in the gonads significantly increased with maturation (from 4.90% to 34.59%) in parallel with the GSI (from 0.8% to 15.5%) to decrease after spawning. Peritoneal fat was probably transitional fat that could be rapidly metabolized or transferred to other tissues but no specific function could be assigned because its presence in previtellogenic and early-vitellogenic females varied greatly. One of the main sources of lipids accumulated in the ovary was most likely diet. The total percentage of ΣMUFA, mainly 17:1 -previously not identified in high quantities in teleost vitellogenic ovaries and likely of bacterial origin- and 16:1, strongly increased in the ovaries with maturation. The 16:1 might be an important source of lipids for embryo development. High percentages of DHA, EPA, and ARA were found in the ovary during previtellogenesis available to be used during gonadal maturation. Understanding lipid and fatty acid changes in broodstock tissues can increase our knowledge of the nutritional requirements of the fish used in aquaculture breeding programs.


Assuntos
Ovário , Smegmamorpha , Feminino , Animais , Ovário/metabolismo , Ácidos Graxos/metabolismo , Gônadas/metabolismo , Fígado/metabolismo , Smegmamorpha/metabolismo
8.
Sci Rep ; 13(1): 1054, 2023 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-36658208

RESUMO

Stable isotope analysis of individual compounds is emerging as a powerful tool to study nutrient origin and conversion in host-parasite systems. We measured the carbon isotope composition of amino acids and glucose in the cestode Schistocephalus solidus and in liver and muscle tissues of its second intermediate host, the three-spined stickleback (Gasterosteus aculeatus), over the course of 90 days in a controlled infection experiment. Similar linear regressions of δ13C values over time and low trophic fractionation of essential amino acids indicate that the parasite assimilates nutrients from sources closely connected to the liver metabolism of its host. Biosynthesis of glucose in the parasite might occur from the glucogenic precursors alanine, asparagine and glutamine and with an isotope fractionation of - 2 to - 3 ‰ from enzymatic reactions, while trophic fractionation of glycine, serine and threonine could be interpreted as extensive nutrient conversion to fuel parasitic growth through one-carbon metabolism. Trophic fractionation of amino acids between sticklebacks and their diets was slightly increased in infected compared to uninfected individuals, which could be caused by increased (immune-) metabolic activities due to parasitic infection. Our results show that compound-specific stable isotope analysis has unique opportunities to study host and parasite physiology.


Assuntos
Cestoides , Infecções por Cestoides , Doenças dos Peixes , Parasitos , Smegmamorpha , Animais , Humanos , Infecções por Cestoides/parasitologia , Isótopos de Carbono , Carbono , Aminoácidos , Cestoides/fisiologia , Smegmamorpha/parasitologia , Nutrientes , Interações Hospedeiro-Parasita , Doenças dos Peixes/parasitologia
9.
Environ Res ; 218: 115001, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36481368

RESUMO

Unconscious and excessive use of plastic supports the diversity and abundance of microplastics (MPs) in marine environments. As a result of MP exposure, organisms in the marine environment are faced with adverse scenarios up to death. In this study, ten-year MP composition was investigated in gastrointestinal tracts (GITs) of low-mobility seahorses (90 individuals per period) from the Southeastern Black Sea. Seahorse GITs sampled during both 2012 and 2022 contain 102 and 135 MP items, respectively. The number of MPs per unit individual seahorse and unit seahorse weight was higher in the 2022 period. On the other hands, no significant differences were observed between the MP lengths of both periods. The majority of MPs in both sample periods were materials shorter than 1000 µm. Of the eight found synthetic polymers, five belonged to the 2012 period, while seven were observed during the 2022 period. Additionally, the most abundant synthetic polymer for both periods is polyvinyl stearate (PVS). As a result, 43% of the total plastic material belonged to the 2012 period, while 57% was observed in the 2022 period. Considering both the diversity of polymers and the abundance of plastics, the region was adversely affected by plastic materials in the 2022 period.


Assuntos
Smegmamorpha , Poluentes Químicos da Água , Humanos , Animais , Microplásticos , Plásticos , Mar Negro , Monitoramento Ambiental , Poluentes Químicos da Água/análise , Trato Gastrointestinal/química
10.
Anim Reprod Sci ; 248: 107161, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36542925

RESUMO

Goldspot mullet, Liza parsia is a commercially important fish of South East Asia, where its farming depends on wild seed resources due to unavailability of hatchery technology. It, therefore, is important to understand the annual reproductive cycle of female L. parsia in captivity. In this study, adult male and female L. parsia (body weight ranges: 45-90 g; total length ranges: 100-125 mm, age >1 year) were collected from the wild and reared in a brackishwater pond. Thereafter, fish were randomly sampled at monthly intervals to measure the hepatosomatic index (HSI), gonadosomatic index (GSI), levels of serum steroids (testosterone, T; 17ß-estradiol, E2 and 17α-hydroxyprogesterone, 17-OHP), and oocyte growth. Results exhibited that female L. parsia undergoes six different maturation stages, namely I (oocyte diameter, OD: <100 µm), II (OD: 100-350 µm), III (OD: 350-400 µm), IV (vitellogenic oocyte, OD: 400-450 µm), V (ripe oocyte, OD: 450-550 µm) and VI (atretic oocyte, OD: 60-150 µm), with synchronous oocyte development. The highest (P < 0.05) HSI (1.96 ± 0.24) and GSI (12.01 ± 0.73) were recorded in December and January, respectively. Concentration of E2 gradually increased from August and reached its peak (807.67 ± 25.98 pg mL-1, P < 0.05) in December. The level of 17-OHP (85.87 ± 0.91 pg mL-1) was at its peak during the normal spawning month (January) (P < 0.05). Overall, the results indicated that L. parsia attains maturity in brackishwater pond, which is consistent with previous observations, and altogether provide the basis to develop a breeding technology in captivity through hormonal and environmental manipulations.


Assuntos
Smegmamorpha , Feminino , Masculino , Animais , Lagoas , Melhoramento Vegetal , Gônadas , Hormônios Esteroides Gonadais , Estradiol , Peixes , Esteroides
11.
Glob Chang Biol ; 29(1): 206-214, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36259414

RESUMO

The costs and benefits of being social vary with environmental conditions, so individuals must weigh the balance between these trade-offs in response to changes in the environment. Temperature is a salient environmental factor that may play a key role in altering the costs and benefits of sociality through its effects on food availability, predator abundance, and other ecological parameters. In ectotherms, changes in temperature also have direct effects on physiological traits linked to social behaviour, such as metabolic rate and locomotor performance. In light of climate change, it is therefore important to understand the potential effects of temperature on sociality. Here, we took the advantage of a 'natural experiment' of threespine sticklebacks from contrasting thermal environments in Iceland: geothermally warmed water bodies (warm habitats) and adjacent ambient-temperature water bodies (cold habitats) that were either linked (sympatric) or physically distinct (allopatric). We first measured the sociability of wild-caught adult fish from warm and cold habitats after acclimation to a low and a high temperature. At both acclimation temperatures, fish from the allopatric warm habitat were less social than those from the allopatric cold habitat, whereas fish from sympatric warm and cold habitats showed no differences in sociability. To determine whether differences in sociability between thermal habitats in the allopatric population were heritable, we used a common garden breeding design where individuals from the warm and the cold habitat were reared at a low or high temperature for two generations. We found that sociability was indeed heritable but also influenced by rearing temperature, suggesting that thermal conditions during early life can play an important role in influencing social behaviour in adulthood. By providing the first evidence for a causal effect of rearing temperature on social behaviour, our study provides novel insights into how a warming world may influence sociality in animal populations.


Assuntos
Smegmamorpha , Animais , Aclimatação , Temperatura , Peixes/fisiologia , Água
12.
Sci Total Environ ; 863: 160844, 2023 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-36528094

RESUMO

Marine heatwaves (MHWs) are becoming more frequent and intense due to climate change and have strong negative effects on ecosystem. Few studies have reproduced the complex nature of temperature changes of a MHW, while it is suggested that ectotherms may be more vulnerable to rapid changes such as during MHWs. Effects of an experimental MHW were investigated in the golden grey mullet Chelon auratus. Juveniles acclimated to 20 °C were exposed to a rapid 5 °C increase in temperature, followed by a five-day period at 25 °C, before quickly returning to 20°C. Metabolic variables (SMR-standard, MMR-maximum rate, AS-aerobic scope, EPOC-excess post­oxygen consumption) and critical swimming speed (Ucrit) were measured at different phases of this MHW and after a thermally stable recovery phase. Although the pattern was only significant for the SMR, the aerobic three variables describing aerobic metabolism (SMR, MMR and AS) immediately increased in fish exposed to the acute elevation of temperature, and remained elevated when fish stayed at 25 °C for five days. A similar increase of these metabolic variables was observed for fish that were progressively acclimated to 25 °C. This suggests that temperature increases contribute to increases in metabolism; however, the acute nature of the MHW had no influence. At the end of the MHW, the SMR remained elevated, suggesting an additional cost of obligatory activities due to the extreme event. In parallel, Ucrit did not vary regardless of the thermal conditions. Concerning EPOC, it significantly increased only when fish were acutely exposed to 25 °C. This strongly suggests that fish may buffer the effects of acute changes in temperature by shifting to anaerobic metabolism. Globally, this species appears able to cope with this MHW, but that's without taking into consideration future projections describing an increase in both intensity and frequency of such events, as well as other stressors like pollution or hypoxia.


Assuntos
Ecossistema , Smegmamorpha , Animais , Anaerobiose , Temperatura , Peixes , Metabolismo Energético
13.
Mol Biol Evol ; 40(1)2023 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-36578180

RESUMO

Unlike birds and mammals, many teleosts have homomorphic sex chromosomes, and changes in the chromosome carrying the sex-determining locus, termed "turnovers", are common. Recent turnovers allow studies of several interesting questions. One question is whether the new sex-determining regions evolve to become completely non-recombining, and if so, how and why. Another is whether (as predicted) evolutionary changes that benefit one sex accumulate in the newly sex-linked region. To study these questions, we analyzed the genome sequences of two seahorse species of the Syngnathidae, a fish group in which many species evolved a unique structure, the male brood pouch. We find that both seahorse species have XY sex chromosome systems, but their sex chromosome pairs are not homologs, implying that at least one turnover event has occurred. The Y-linked regions occupy 63.9% and 95.1% of the entire sex chromosome of the two species and do not exhibit extensive sequence divergence with their X-linked homologs. We find evidence for occasional recombination between the extant sex chromosomes that may account for their homomorphism. We argue that these Y-linked regions did not evolve by recombination suppression after the turnover, but by the ancestral nature of the low crossover rates in these chromosome regions. With such an ancestral crossover landscape, a turnover can instantly create an extensive Y-linked region. Finally, we test for adaptive evolution of male pouch-related genes after they became Y-linked in the seahorse.


Assuntos
Smegmamorpha , Animais , Gravidez , Feminino , Smegmamorpha/genética , Evolução Molecular , Cromossomos Sexuais/genética , Genoma , Mamíferos/genética
14.
Mar Pollut Bull ; 186: 114466, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36502772

RESUMO

This study assessed the tissue distribution, dietary intake, and potential health risks of eight OPPs in Pomadasys commersonnii (Spotted grunter) and Mugil cephalus (Flathead mullet) from the Sundays and Swartkops estuaries in South Africa. The highest concentration in fish tissues was found in muscles of M. cephalus (178 ± 80.4 ng/g ww) and P. commersonnii (591 ± 280 ng/g ww) from Sundays Estuary. The ∑6OPPs concentration in muscles from both fish species was higher in muscles than in the gills with fenitrothion dominating the distribution profile. Results from the path analysis indicate that lipid, weights, and length of the fish species do not influence the concentration of OPPs in the studied fish species. The calculated hazard ratios, which represent the non-carcinogenic risks, were less than one for all OPPs, indicating that the concentration of OPPs detected in fish muscles had negligible consequences on human health.


Assuntos
Inseticidas , Praguicidas , Smegmamorpha , Poluentes Químicos da Água , Animais , Humanos , África do Sul , Estuários , Monitoramento Ambiental/métodos , Distribuição Tecidual , Poluentes Químicos da Água/análise , Peixes , Inseticidas/análise , Compostos Organofosforados/análise , Medição de Risco , Ingestão de Alimentos , Organofosfatos/análise , Praguicidas/análise
15.
Food Chem ; 407: 135130, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-36527945

RESUMO

In this study, seahorse peptide (SHP) was isolated from an alcalase-treated hydrolysate from Hippocampus abdominalis and assessed for its antioxidant potential against AAPH-induced oxidative stress damage. AAPH stimulation significantly decreased cell viability and increased intracellular reactive oxygen species (ROS) production in Vero cells. SHP treatment increased cell viability and remarkably lowered ROS production under AAPH-induced oxidative stress. Furthermore, it protected against AAPH-induced apoptotic DNA damage. Western blot analysis demonstrated that SHP treatment remarkably increased the protein expression levels of catalase and SOD in AAPH-induced Vero cells. A zebrafish study revealed that SHP-treated zebrafish embryos resulted in lower cell death, ROS generation, and lipid peroxidation than the AAPH-treated group. These results suggest that SHP is a potent functional antioxidant that could be developed as a natural antioxidant in the food and functional food industries.


Assuntos
Antioxidantes , Smegmamorpha , Animais , Chlorocebus aethiops , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Peixe-Zebra/genética , Peixe-Zebra/metabolismo , Células Vero , Smegmamorpha/genética , Smegmamorpha/metabolismo , Estresse Oxidativo , Peptídeos/farmacologia , Peptídeos/metabolismo
16.
Proc Biol Sci ; 289(1984): 20221462, 2022 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-36476008

RESUMO

Stressful environmental conditions can shape both an individual's phenotype and that of its offspring. However, little is known about transgenerational effects of chronic (as opposed to acute) stressors, nor whether these vary across the breeding lifespan of the parent. We exposed adult female (F0 generation) three-spined sticklebacks (Gasterosteus aculeatus) to chronic environmental stressors and compared their reproductive allocation with that of non-exposed controls across early, middle and late clutches produced within the single breeding season of this annual population. There was a seasonal trend (but no treatment difference) in F0 reproductive allocation, with increases in egg mass and fry size in late clutches. We then tested for transgenerational effects in the non-exposed F1 and F2 generations. Exposure of F0 females to stressors resulted in phenotypic change in their offspring and grandoffspring that were produced late in their breeding lifespan: F1 offspring produced from the late-season clutches of stressor-exposed F0 females had higher early life survival, and subsequently produced heavier eggs and F2 fry that were larger at hatching. Changed maternal allocation due to a combination of seasonal factors and environmental stressors can thus have a transgenerational effect by influencing the reproductive allocation of daughters, especially those born late in life.


Assuntos
Smegmamorpha , Estresse Fisiológico , Animais , Feminino , Masculino
17.
J Parasitol ; 108(6): 613-626, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-36538390

RESUMO

Prosogonotrema iraqiense n. sp. (Sclerodistomidae: Prosogonotrematinae) is described in the flathead grey mullet, Mugil cephalus Linnaeus (Mugiliformes: Mugilidae), collected from the Arabian Gulf off Iraq during June and October 2019. Currently there are 11 species of ProsogonotremaVigueras, 1940 commonly accepted: Prosogonotrema arabicaYadav, 1980; Prosogonotrema bilabiatumVigueras, 1940 (type species); Prosogonotrema caesionisGu and Shen, 1979; Prosogonotrema diacanthiBilqees and Durrani, 1980; Prosogonotrema karachienseBilqees and Durrani, 1980; Prosogonotrema pavasiLokhande, 1990; Prosogonotrema piscicola (Srivastava, 1949) Gibson, 2002 (Syn. Bhaleraoia piscicolaSrivastava, 1949); Prosogonotrema plataxumGu and Shen, 1979; Prosogonotrema posterouterinaYadav, 1980; and Prosogonotrema symmetricumOshmarin, 1965 originally described from marine fishes, and Prosogonotrema nickoliBilqees and Khan, 1992 described from a freshwater cyprinid. Six additional species that have been considered synonyms of P. bilabiatum are also considered. Prosogonotrema diacanthi is considered a junior synonym of P. piscicola and Prosogonotrema carangiHussain and Rao, 1980nec Velasquez, 1961 is determined to be a species distinct from P. bilabiatum and is reassigned herein as Prosogonotrema aluteri nomen novum per the ICZN. Prosogonotrema iraqiense differs from all currently recognized species in the genus by having the width of the ventral sucker approach or exceed the width of the body and from all except P. pavasi (body length/width ratio 1:1.4-1:1.5) by having a distinctive narrower, more elongate body profile with a larger body length/width ratio (1:5.8-1:6.1 vs. 1: 2.0-1:4.1). A key to the 18 species we recognize in Prosogonotrema is included.


Assuntos
Smegmamorpha , Trematódeos , Animais , Iraque
18.
Artigo em Inglês | MEDLINE | ID: mdl-36497865

RESUMO

Accumulation of pesticides has a harmful impact on the environment and human health. The main goal of this work was to develop a method to determine and quantify the residues of thirteen pesticides in edible fish and bivalves such as parati (Mugil curema), seabass (Centropomus ssp.), mullet (Mugil brasiliensis), clams (Anomalocardia brasiliana) and mussel (Mytilus galloprovincialis) collected from Sepetiba Bay and Parnaiba River Delta (Brazil) between 2019 and 2020. Matrix solid-phase dispersion (MSPD) was used for extraction and quantification through gas chromatography coupled to tandem mass spectrometry (GC-MS/MS). The method was validated (linearity, accuracy and precision) for fatty fish (Salmo salar), lean fish (Mugil curema) and bivalves (Mytilus edulis). The survey found linear correlation coefficients (r) equal to or greater than 0.9 for almost all analytes. The relative standard deviations (RSD) of five replicates were less than 20% for almost all analytes at different concentrations in lean fish, fatty fish and bivalves. Most analytes showed satisfactory accuracy. Alachlor herbicide was found in samples of seabass, mussels, clams and parati with levels ranging between 0.55 to 420.39 µg kg-1 dw. Ethion was found in parati (maximum 211.22 µg kg-1 dw), mussels (15.1 µg kg-1 dw) and clams (maximum 44.50 µg kg-1 dw). Alachlor was found in clams (maximum 93.1 µg kg-1 dw), and bifenthrin was found in parati (maximum 43.4 µg kg-1 dw) and clams (maximum 42.21 µg kg-1 dw). The validated method was satisfactory for the determination of eleven pesticides in the fatty fish matrix, and thirteen pesticides in the samples of lean fish and bivalves. The presence of alachlor, ethion and bifenthrin stands out.


Assuntos
Bivalves , Praguicidas , Smegmamorpha , Animais , Humanos , Espectrometria de Massas em Tandem/métodos , Baías , Agroquímicos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Bivalves/química , Peixes , Praguicidas/análise , Extração em Fase Sólida/métodos
19.
Nat Commun ; 13(1): 7610, 2022 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-36494371

RESUMO

In the highly derived syngnathid fishes (pipefishes, seadragons & seahorses), the evolution of sex-role reversed brooding behavior culminated in the seahorse lineage's male pregnancy, whose males feature a specialized brood pouch into which females deposit eggs during mating. Then, eggs are intimately engulfed by a placenta-like tissue that facilitates gas and nutrient exchange. As fathers immunologically tolerate allogenic embryos, it was suggested that male pregnancy co-evolved with specific immunological adaptations. Indeed, here we show that a specific amino-acid replacement in the tlx1 transcription factor is associated with seahorses' asplenia (loss of spleen, an organ central in the immune system), as confirmed by a CRISPR-Cas9 experiment using zebrafish. Comparative genomics across the syngnathid phylogeny revealed that the complexity of the immune system gene repertoire decreases as parental care intensity increases. The synchronous evolution of immunogenetic alterations and male pregnancy supports the notion that male pregnancy co-evolved with the immunological tolerance of the embryo.


Assuntos
Smegmamorpha , Feminino , Animais , Masculino , Smegmamorpha/genética , Comportamento Sexual Animal , Peixe-Zebra , Reprodução/genética , Mutação
20.
Am Nat ; 200(6): 846-856, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36409977

RESUMO

AbstractFor a species to expand its range, it needs to be good at dispersing and also capable of exploiting resources and adapting to different environments. Therefore, behavioral and cognitive traits could play key roles in facilitating invasion success. Marine threespined sticklebacks (Gasterosteus aculeatus) have repeatedly colonized freshwater environments and rapidly adapted to them. Here, by comparing the behavior of hundreds of lab-reared sticklebacks from six different populations, we show that marine sticklebacks are bold, while sticklebacks that have become established in freshwater lakes are flexible. Moreover, boldness and flexibility are negatively correlated with one another at the individual, family, and population levels. These results support the hypothesis that boldness is favored in invaders during the initial dispersal stage, while flexibility is favored in recent immigrants during the establishment stage, and they suggest that the link between boldness and flexibility facilitates success during both the dispersal stage and the establishment stage. This study adds to the growing body of work showing the importance of behavioral correlations in facilitating colonization success in sticklebacks and other organisms.


Assuntos
Smegmamorpha , Animais , Lagos , Adaptação Fisiológica , Fenótipo
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