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1.
Mol Plant Microbe Interact ; 36(6): 359-371, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36802868

RESUMO

Eicosapolyenoic fatty acids are integral components of oomycete pathogens that can act as microbe-associated molecular patterns to induce disease resistance in plants. Defense-inducing eicosapolyenoic fatty acids include arachidonic acid (AA) and eicosapentaenoic acid and are strong elicitors in solanaceous plants, with bioactivity in other plant families. Similarly, extracts of a brown seaweed, Ascophyllum nodosum, used in sustainable agriculture as a biostimulant of plant growth, may also induce disease resistance. A. nodosum, similar to other macroalgae, is rich in eicosapolyenoic fatty acids, which comprise as much as 25% of total fatty acid composition. We investigated the response of roots and leaves from AA or a commercial A. nodosum extract (ANE) on root-treated tomatoes via RNA sequencing, phytohormone profiling, and disease assays. AA and ANE significantly altered transcriptional profiles relative to control plants, inducing numerous defense-related genes with both substantial overlap and differences in gene expression patterns. Root treatment with AA and, to a lesser extent, ANE also altered both salicylic acid and jasmonic acid levels while inducing local and systemic resistance to oomycete and bacterial pathogen challenge. Thus, our study highlights overlap in both local and systemic defense induced by AA and ANE, with potential for inducing broad-spectrum resistance against pathogens. [Formula: see text] Copyright © 2023 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.


Assuntos
Oomicetos , Alga Marinha , Solanum lycopersicum , Solanum lycopersicum/genética , Ácidos Graxos , Resistência à Doença , Plantas , Extratos Vegetais , Doenças das Plantas/microbiologia
2.
Phytopathology ; 113(6): 1084-1092, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36598344

RESUMO

Arachidonic acid (AA) is an oomycete-derived microbe-associated molecular pattern (MAMP) capable of eliciting robust defense responses and inducing resistance in plants. Similarly, Ascophylum nodosum extract (ANE) from the brown seaweed A. nodosum, a plant biostimulant that contains AA, can also prime plants for defense against pathogen challenges. A previous parallel study comparing the transcriptomes of AA- and ANE-root-treated tomatoes demonstrated significant overlap in transcriptional profiles, a shared induced resistance phenotype, and changes in the accumulation of various defense-related phytohormones. In this work, untargeted metabolomic analysis via liquid chromatography-mass spectrometry was conducted to investigate the local and systemic metabolome-wide remodeling events elicited by AA and ANE root treatment in tomatoes. Our study demonstrated AA and ANE's capacity to locally and systemically alter the metabolome of tomatoes with enrichment of chemical classes and accumulation of metabolites associated with defense-related secondary metabolism. AA- and ANE-root-treated plants showed enrichment of fatty acyl-glycosides and strong modulation of hydroxycinnamic acids and derivatives. Identification of specific metabolites whose accumulation was affected by AA and ANE treatment revealed shared metabolic changes related to ligno-suberin biosynthesis and the synthesis of phenolic compounds. This study highlights the extensive local and systemic metabolic changes in tomatoes induced by treatment with a fatty acid MAMP and a seaweed-derived plant biostimulant with implications for induced resistance and crop improvement.


Assuntos
Ascophyllum , Oomicetos , Solanum lycopersicum , Solanum lycopersicum/genética , Ascophyllum/química , Ácido Araquidônico , Doenças das Plantas , Metaboloma
3.
Curr Biol ; 32(24): 5398-5405.e3, 2022 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-36538877

RESUMO

Marine tetrapods occupy important roles in modern marine ecosystems and often gather in large aggregations driven by patchy prey distribution,1,2 social or reproductive behaviors,3,4 or oceanographic factors.5 Here, we show that similar grouping behaviors evolved in an early marine tetrapod lineage, documented by dozens of specimens of the giant ichthyosaur Shonisaurus in the Luning Formation in West Union Canyon, Nevada, USA.6,7 A concentration of at least seven skeletons closely preserved on a single bedding plane received the bulk of previous attention. However, many more specimens are preserved across ∼106 square meters and ∼200 stratigraphic meters of outcrop representing an estimated >105-6 years. Unlike other marine-tetrapod-rich deposits, this assemblage is essentially monotaxic; other vertebrate fossils are exceptionally scarce. Large individuals are disproportionately abundant, with the exception of multiple neonatal or embryonic specimens, indicating an unusual demographic composition apparently lacking intermediate-sized juveniles or subadults. Combined with geological evidence, our data suggest that dense aggregations of Shonisaurus inhabited this moderately deep, low-diversity, tropical marine environment for millennia during the latest Carnian Stage of the Late Triassic Period (237-227 Ma). Thus, philopatric grouping behavior in marine tetrapods, potentially linked to reproductive activity, has an antiquity of at least 230 million years.


Assuntos
Ecossistema , Fósseis , Humanos , Recém-Nascido , Filogenia , Oceanografia , Evolução Biológica
4.
Equine Vet J ; 2021 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-34478179

RESUMO

BACKGROUND: Laminitis causes lameness in donkeys, but its prevalence and factors associated with disease remain uncertain. OBJECTIVES: To determine the prevalence of and identify factors associated with laminitis in donkeys. STUDY DESIGN: Retrospective cross-sectional study. METHODS: All donkeys at the Donkey Sanctuary, UK, October 2015 to March 2019 were included. For animals that had laminitis during this period, age, sex, weight, body condition score, and the onset date and type of each episode (first or recurrent, acute or chronic) were recorded. Additionally, management data, foot lesion score, endocrine data, other medical conditions, occurrence of foot trimming, surgical procedures, diagnostic imaging, behavioural modification therapy or movement between farms within the month prior were noted. Controls were animals that did not experience laminitis during this period and similar data were recorded. Multivariable logistic regression modelling assessed the differences between the control group and laminitis outcome groups (first, all laminitis, acute and chronic episodes). RESULTS: Altogether, 707 animals were included; 364 were control animals; 343 had a first episode of laminitis during the study period, of which 200/343 had no further episodes and 143/343 had recurrent episodes resulting in a total of 512 laminitis episodes and the period prevalence was 48.5% over 42 months. Overall, 180/512 (35%) laminitis episodes were acute and 332/512 (65%) were chronic. Compared with control animals, the laminitic outcome groups were significantly (P < .05) more likely to be younger (first episode), less likely to get extra feed (all four groups) or have an additional medical problem (first episode), and less likely to have undergone dental work, movement, imaging (all four groups) or surgery (first; all laminitis, chronic episodes) in the month preceding the episode. MAIN LIMITATIONS: These results may not be applicable to the wider donkey population. CONCLUSIONS: Laminitis commonly affects donkeys, but factors associated with donkey laminitis differ from those reported in horses.

5.
PLoS One ; 16(2): e0247830, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33630957

RESUMO

Knowing how many donkeys there are in specific countries where welfare is compromised is a key concern for targeting efforts to improve donkey welfare. Additionally, accurate population estimates are vital for providing evidence and addressing the impact of population threats. The FAO annually report the number of donkeys and mules in each country. The last paper to investigate global and region trends dates back to 2000 and used FAO data from 1961 to 1997. This paper is an update focusing on global, regional and country level donkey and mule populations to understand if there have been any changes in the trends reported by the previous study between 1997 and 2018. Results show that the general trend identified between 1961 and 1997 is continuing with the number of donkeys globally increasing at a rate of ~1% per annum whilst mule populations are in decline at a rate of ~2% per annum. Results also suggest that the trend identified in the original paper are still evident today with the largest increases in donkey population seen in the sub-Saharan African region and greatest reduction noted in Eastern Europe with these two regions having different socio-economic drivers influencing these changes. These results highlight the multifaceted socio-economic drivers influence changes in donkey and mule populations demonstrating the complexity of designing targeted one-welfare approaches. Whilst the FAO donkey and mule datasets are the best available for understanding spatial-temporal distributions in populations there needs to be greater effort to promote the communication of information from the country level to the FAO. This can be directly supported by NGO's by promoting the robustness of the FAO process for collating and disseminating this information. NGO's should also seek to highlight the importance of this information for understanding global regional and country level drivers for equid population changes and potential threats to welfare as well as using this information to facilitate projects that support one-welfare approaches.


Assuntos
Equidae , Gado , Animais , Bases de Dados Factuais , Densidade Demográfica
6.
Animals (Basel) ; 10(6)2020 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-32580418

RESUMO

Equids fulfil many different roles within communities. In low- to middle-income countries (LMICs), in addition to providing a source of income, equids also provide essential transport of food, water, and goods to resource-limited and/or isolated communities that might otherwise lack access. The aim of this investigation was to understand the welfare conditions that donkeys, mules, and horses are exposed to whilst working in Nepalese brick kilns. To understand the welfare conditions of equids in Nepalese brick kilns, the Welfare Aggregation and Guidance (WAG) tool in conjunction with the Equid Assessment, Research and Scoping (EARS) tool was used to understand the health, behaviour, nutrition, living and working conditions in brick kilns. Further analysis of individual EARS responses focused on key indicator questions relating to demographic information was used to investigate specific areas of welfare concern and attitudes of handlers towards their equids. Trained staff carried out welfare assessments between December 2018 and April 2019. The information gathered using the EARS tool was summarised using the WAG tool to pinpoint areas of welfare concern and suggest possible strategies to mitigate poor welfare conditions and suggest areas to improve the welfare of equids. Overall, the results indicate that to improve the welfare of equids working in Nepalese brick kilns, there should be better provision of clean water, both when working and stabled, equipment should be removed and shade provided during rest periods, with improvements made to housing to allow the equids to rest and recuperate when not working. Further work should also focus on collaborating with owners and equid handlers to improve their attitudes and practices towards their equids. Such improvements can be implemented via training of equid handlers and kiln owners whilst using the EARS and WAG tools to provide a sound basis on which to monitor the effectiveness and impact of education programs on equid welfare.

7.
Animals (Basel) ; 10(2)2020 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-32069910

RESUMO

The assessment of animal welfare poses numerous challenges, yet an emerging approach is the consolidation of existing knowledge into new frameworks which can offer standardised approaches to welfare assessment across a variety of contexts. Multiple tools exist for measuring the welfare of equids, but such tools have typically been developed for specific contexts. There is no 'one size fits all' which means that resulting datasets are generally non-comparable, creating a barrier to knowledge-sharing and collaboration between the many organisations working to improve equid welfare around the globe. To address this, we developed the Equid Assessment, Research and Scoping (EARS) tool, which incorporates pre-existing validated welfare assessment methods alongside new welfare indicators to deliver a larger and more comprehensive series of welfare indicators than currently exists, creating a single resource that can be used to assess equid welfare in any context. We field-trialled three welfare assessment protocols within the EARS tool, and applied these to welfare assessment of equids in a variety of contexts across nineteen countries. The EARS tool proved a useful, versatile and rapid method for collecting welfare assessment data and we collected 7464 welfare assessments in a period of fifteen months. We evaluate the EARS tool and provide ideas for future development.

8.
PLoS One ; 11(12): e0166912, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27935999

RESUMO

With the number of threatened species increasing globally, conservation breeding is vitally important now more than ever. However, no previous peer-reviewed study has attempted to determine how the varying conditions across zoos have influenced breeding by an extinct-in-the-wild species. We therefore use questionnaires and studbook data to evaluate the influence of husbandry practices and enclosure design on scimitar-horned oryx (Oryx dammah) breeding success, at the herd level. Regression models were used to identify the variables that best predicted breeding success among 29 zoos across a five-year period. Calf survival decreased with herd age and the use of soft substrates in hardstand areas (yard area usually adjacent to the indoor housing), explaining 30.7% of overall variation. Calf survival also decreased where herds were small and where food provisions were not raised (and hence likely incited competition), although these were less influential. Likewise, birth rate decreased with soft substrates in hardstand areas and unraised food provisions, although these were less influential than for calf survival. Birth rate increased with year-round male presence, yet this decreased calf survival. Compared to previous studies, the number of enclosure/husbandry influences on breeding were relatively few. Nevertheless, these few enclosure/husbandry influences explained over one third of the variation in calf survival. Our data therefore suggest some potential improvements and hence that extinct-in-the-wild species stand a greater chance of survival with empirical design of zoo enclosures and husbandry methods.


Assuntos
Antílopes/fisiologia , Conservação dos Recursos Naturais/métodos , Espécies em Perigo de Extinção , Extinção Biológica , Fatores Etários , Criação de Animais Domésticos/métodos , Criação de Animais Domésticos/estatística & dados numéricos , Animais , Animais de Zoológico , Cruzamento , Conservação dos Recursos Naturais/estatística & dados numéricos , Feminino , Abrigo para Animais/normas , Abrigo para Animais/estatística & dados numéricos , Masculino , Densidade Demográfica , Análise de Regressão , Reprodução/fisiologia , Inquéritos e Questionários
9.
Zoo Biol ; 35(5): 385-397, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27486862

RESUMO

Multi-zoo comparisons of animal welfare are rare, and yet vital for ensuring continued improvement of zoo enclosures and husbandry. Methods are not standardized for the development of zoo enclosures based on multiple indicators, and case study species are required. This study compares behavior and breeding success to various enclosure and husbandry parameters for the Humboldt penguin, Spheniscus humboldti, for the development of improved enclosure design. Behavioral sampling was completed at Flamingo Land over a period of 8 months. Further data on behavior, enclosure design, and breeding success were collected via questionnaires, visits to zoos, and literature review. Breeding success was primarily influenced by colony age and number of breeding pairs, suggesting an important social influence on reproduction. Across zoos, there was also significant variation in behavior. The proportion of time spent in water varied between zoos (2-23%) and was used as an indicator of physical activity and natural behavior. Regression models revealed that water-use was best predicted by total enclosure area per penguin, followed by land area, with some evidence for positive influence of pool surface area per penguin. Predominantly linear/curvilinear increases in our biological indicators with enclosure parameters suggest that optimal conditions for S. humboldti were not met among the selected zoos. We propose revised minimum conditions for S. humboldti enclosure design, which exceed those in the existing husbandry guidelines. We present a framework for the evaluation of zoo enclosures and suggest that a rigorous scientific protocol be established for the design of new enclosures, based on multivariate methods. Zoo Biol. 35:385-397, 2016. © Wiley Periodicals, Inc.


Assuntos
Criação de Animais Domésticos/normas , Animais de Zoológico/fisiologia , Comportamento Animal/fisiologia , Conservação dos Recursos Naturais , Abrigo para Animais/normas , Spheniscidae/fisiologia , Bem-Estar do Animal , Animais , Cruzamento , Análise de Regressão , Reprodução/fisiologia
10.
PeerJ ; 3: e1227, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26355720

RESUMO

In contrast to dominant mode of ecological transition in the evolution of marine mammals, different lineages of toothed whales (Odontoceti) have repeatedly invaded freshwater ecosystems during the Cenozoic era. The so-called 'river dolphins' are now recognized as independent lineages that converged on similar morphological specializations (e.g., longirostry). In South America, the two endemic 'river dolphin' lineages form a clade (Inioidea), with closely related fossil inioids from marine rock units in the South Pacific and North Atlantic oceans. Here we describe a new genus and species of fossil inioid, Isthminia panamensis, gen. et sp. nov. from the late Miocene of Panama. The type and only known specimen consists of a partial skull, mandibles, isolated teeth, a right scapula, and carpal elements recovered from the Piña Facies of the Chagres Formation, along the Caribbean coast of Panama. Sedimentological and associated fauna from the Piña Facies point to fully marine conditions with high planktonic productivity about 6.1-5.8 million years ago (Messinian), pre-dating the final closure of the Isthmus of Panama. Along with ecomorphological data, we propose that Isthminia was primarily a marine inhabitant, similar to modern oceanic delphinoids. Phylogenetic analysis of fossil and living inioids, including new codings for Ischyrorhynchus, an enigmatic taxon from the late Miocene of Argentina, places Isthminia as the sister taxon to Inia, in a broader clade that includes Ischyrorhynchus and Meherrinia, a North American fossil inioid. This phylogenetic hypothesis complicates the possible scenarios for the freshwater invasion of the Amazon River system by stem relatives of Inia, but it remains consistent with a broader marine ancestry for Inioidea. Based on the fossil record of this group, along with Isthminia, we propose that a marine ancestor of Inia invaded Amazonia during late Miocene eustatic sea-level highs.

11.
Planta ; 240(4): 797-808, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25066672

RESUMO

MAIN CONCLUSION: Floral primordia-targeted expression of the ethylene biosynthetic gene, ACS , in melon suggests that differential timing and ethylene response thresholds combine to promote carpels, inhibit stamens, and prevent asexual bud formation. Typical angiosperm flowers produce both male and female reproductive organs. However, numerous species have evolved unisexuality. Melons (Cucumis melo L.) can produce varying combinations of male, female or bisexual flowers. Regardless of final sex, floral development begins with sequential initiation of all four floral whorls; unisexuality results from carpel or stamen primordia arrest regulated by the G and A loci, respectively. Ethylene, which promotes femaleness, is a key factor regulating sex expression. We sought to further understand the location, timing, level, and relationship to sex gene expression required for ethylene to promote carpel development or inhibit stamen development. Andromonoecious melons (GGaa) were transformed with the ethylene biosynthetic enzyme gene, ACS (1-aminocyclopropane-1-carboxylate synthase), targeted for expression in stamen and petal, or carpel and nectary, primordia using Arabidopsis APETALA3 (AP3) or CRABSCLAW (CRC) promoters, respectively. CRC::ACS plants did not exhibit altered sex phenotype. AP3::ACS melons showed increased femaleness manifested by gain of a bisexual-only phase not seen in wild type, decreased male buds and flowers, and loss of the initial male-only phase. In extreme cases, plants became phenotypically hermaphrodite, rather than andromonoecious. A reduced portion of buds progressed beyond initial whorl formation. Both the ACS transgene and exogenous ethylene reduced the expression of the native carpel-suppressing gene, G, while elevating expression of the stamen-suppressing gene, A. These results show ethylene-mediated regulation of key sex expression genes and suggest a mechanism by which temporally regulated ethylene production and differential ethylene response thresholds can promote carpels, inhibit stamens, and prevent the formation of asexual buds.


Assuntos
Cucumis melo/enzimologia , Etilenos/metabolismo , Flores/enzimologia , Liases/genética , Reguladores de Crescimento de Plantas/metabolismo , Arabidopsis/genética , Cucumis melo/efeitos dos fármacos , Cucumis melo/genética , Cucumis melo/crescimento & desenvolvimento , Flores/efeitos dos fármacos , Flores/genética , Flores/crescimento & desenvolvimento , Regulação da Expressão Gênica de Plantas , Liases/metabolismo , Compostos Organofosforados/farmacologia , Fenótipo , Reguladores de Crescimento de Plantas/farmacologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas , Regiões Promotoras Genéticas/genética
12.
Proc Biol Sci ; 281(1781): 20133316, 2014 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-24573855

RESUMO

Marine mammal mass strandings have occurred for millions of years, but their origins defy singular explanations. Beyond human causes, mass strandings have been attributed to herding behaviour, large-scale oceanographic fronts and harmful algal blooms (HABs). Because algal toxins cause organ failure in marine mammals, HABs are the most common mass stranding agent with broad geographical and widespread taxonomic impact. Toxin-mediated mortalities in marine food webs have the potential to occur over geological timescales, but direct evidence for their antiquity has been lacking. Here, we describe an unusually dense accumulation of fossil marine vertebrates from Cerro Ballena, a Late Miocene locality in Atacama Region of Chile, preserving over 40 skeletons of rorqual whales, sperm whales, seals, aquatic sloths, walrus-whales and predatory bony fish. Marine mammal skeletons are distributed in four discrete horizons at the site, representing a recurring accumulation mechanism. Taphonomic analysis points to strong spatial focusing with a rapid death mechanism at sea, before being buried on a barrier-protected supratidal flat. In modern settings, HABs are the only known natural cause for such repeated, multispecies accumulations. This proposed agent suggests that upwelling zones elsewhere in the world should preserve fossil marine vertebrate accumulations in similar modes and densities.


Assuntos
Organismos Aquáticos , Fósseis , Proliferação Nociva de Algas , Mamíferos , Animais , Chile , Microscopia Eletrônica de Varredura , Oceano Pacífico , Especificidade da Espécie , Análise Espectral
13.
Plant Cell ; 25(12): 4812-26, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24368792

RESUMO

Experimental approaches targeting carotenoid biosynthetic enzymes have successfully increased the seed ß-carotene content of crops. However, linkage analysis of seed carotenoids in Arabidopsis thaliana recombinant inbred populations showed that only 21% of quantitative trait loci, including those for ß-carotene, encode carotenoid biosynthetic enzymes in their intervals. Thus, numerous loci remain uncharacterized and underutilized in biofortification approaches. Linkage mapping and genome-wide association studies of Arabidopsis seed carotenoids identified CAROTENOID cleavage dioxygenase4 (CCD4) as a major negative regulator of seed carotenoid content, especially ß-carotene. Loss of CCD4 function did not affect carotenoid homeostasis during seed development but greatly reduced carotenoid degradation during seed desiccation, increasing ß-carotene content 8.4-fold relative to the wild type. Allelic complementation of a ccd4 null mutant demonstrated that single-nucleotide polymorphisms and insertions and deletions at the locus affect dry seed carotenoid content, due at least partly to differences in CCD4 expression. CCD4 also plays a major role in carotenoid turnover during dark-induced leaf senescence, with ß-carotene accumulation again most strongly affected in the ccd4 mutant. These results demonstrate that CCD4 plays a major role in ß-carotene degradation in drying seeds and senescing leaves and suggest that CCD4 orthologs would be promising targets for stabilizing and increasing the level of provitamin A carotenoids in seeds of major food crops.


Assuntos
Proteínas de Arabidopsis/fisiologia , Arabidopsis/enzimologia , Dioxigenases/fisiologia , Proteínas de Plantas/fisiologia , beta Caroteno/biossíntese , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Senescência Celular , Mapeamento Cromossômico , Dioxigenases/genética , Dioxigenases/metabolismo , Homeostase , Mutagênese Insercional , Folhas de Planta/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas , Sementes/genética , Sementes/metabolismo , Deleção de Sequência
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