Artigos em revistas internacionais_ESAS
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- Reproductive traits of the European catfish, Silurus glanis, during the early stages of invasionPublication . Gkenas, C.; Sequeira, V.; Ribeiro, D.; Gago, João; Dias, D.; Verma, C.R.; Kumkar, P.; Ribeiro, F.In recent decades, the European catfish Silurus glanis has spread across Europe and elsewhere, significantly impacting the native fauna of the recipient ecosystems. Studies on its reproductive traits from its non-native range are limited, although this is a critical step in developing effective management plans. Here, we explore the reproductive characteristics of invasive European catfish populations in the Lower River Tagus in Portugal, focusing on its sex ratio, size at maturity, spawning period, fecundity and oocyte diameter. European catfish were collected monthly by electrofishing, gill nets, baited hooks, and professional fishermen from January 2022 to November 2023. A total of 217 females, 156 males and 301 immature fish were analysed. The female-to-male sex ratio was 1.4 : 1, with females and males reaching size at first maturity (TL50) at 72.9 and 68.8 cm total length, respectively. The spawning season was protracted, from February to June, showing asynchronous oocyte development patterns. The absolute fecundity was positively correlated with total length and total weight and ranged from 8,364 to 319,000 oocytes. Relative fecundity varied from 4.39 to 23.53 oocytes, with the mean diameter of the matured oocytes ranging from 1.50 to 3.21 mm. The results obtained in this study enhance our understanding of the reproductive biology of invasive species and can contribute to the development of effective management strategies, such as population control and density- dependent fecundity strategies.
- Nutritional and microbial quality of edible insect powder from plant-based industrial by-product and fish biowaste dietsPublication . Andrade, R.; Martins, L.L.; Mourato, M.P.; Lourenço, H.; Ramos, A.C.; Roseiro, C.; Pereira, N.; Costa, G.J.; Lucas, R.; Alvarenga, N.; Reis, J.; Neves, Ana; Oliveira, Margarida; Dias, Igor; Abreu, M.Edible insect powder, particularly from the cricket Acheta domesticus L., is a promising sustainable alternative to traditional livestock-derived protein. Insects provide high protein content, fibre, and essential minerals, making them suitable for food applications. This study investigates the viability of alternative diets for rearing A. domesticus. Two experimental diets were tested: RI [50% horticultural by-products (HP) + 50% commercial diet (CD)] and RII (33% HP + 33% CD + 33% fish by-products). The results demonstrated that both diets were suitable for cricket rearing. Crickets reared on diets RI and RII produced, respectively, insect powders FI and FII, which were evaluated for their nutritional, bioactive, and microbiological attributes. Both powders exhibited high protein content (≈60%), all essential amino acids, higher mineral content than traditional protein sources, and met European Union food safety standards. Diet composition influenced powder characteristics: FI showed higher antioxidant activity and saturated fat content, while FII contained more protein, ash, minerals, and monounsaturated fatty acids. These findings underscore the potential of using industrial by-products to promote a circulareconomy in insect farming and suggest pathways for further research. However, since insects can bioaccumulate toxic elements, such as Hg, from diets, caution should be taken when considering fish by-products
- Methods of protein extraction from house crickets (Acheta domesticus) for food purposesPublication . Cunha, Nair; Falcão Espada Lopes de Andrade, Vanda Maria; Macedo, Antónia; Lúcia da Mata Silvério Ruivo, Paula; Basto de Lima, Maria GabrielaGlobal population is projected to reach 9.1 billion by 2050, emphasizing the need for increased food production. Edible insects, such as house crickets (Acheta domesticus), emerged as promising due to higher nutritional value and efficient feed conversion rates compared to conventional protein sources. Incorporating insect powders into new food products can improve consumer acceptance but often leads to poor technological food processing functionality and/or undesirable organoleptic characteristics. Protein isolates have proven to be effective in enhancing this functionality and consumer acceptance, but existent protein extraction methods still lack improvements concerning the optimization of protein extraction rates. This study aimed to address this gap by developing and comparing the yield of three different protein extraction methods using sodium hydroxide, ascorbic acid or alcalase from house crickets (Acheta domesticus) for food applications. Protein extraction was performed on cricket powder with a mean protein content of 46.35 g/100 g, and the results were evaluated. The enzymatic method shows the highest protein extraction rate at 69.91% with a mean protein content of 60.19 g/100 g, while extraction with NaOH or ascorbic acid resulted in rates of 60.44 and 46.34%, respectively. Further studies on technological food processing functionality and sensorial evaluation of products developed with this protein extract are recommended.
- A Fish-Based Tool for the Quality Assessment of Portuguese Large RiversPublication . Faro, António Tovar; Ferreira, Maria Teresa; Oliveira, João ManuelMultimetric indices play a pivotal role in assessing river ecological quality, aligning with the European Water Framework Directive (EU WFD) requirements. However, indices developed specifically for large rivers are uncommon. Our objective was to develop a fish-based tool specifically tailored to assess the ecological quality in Portuguese large rivers. Data were collected from seven sites in each of three Portuguese large rivers (Minho, Guadiana, and Tagus). Each site was classified using an environmental disturbance score, combining different pressure types, such as water chemistry, land use, and hydromorphological alterations. The Fish-based Multimetric Index for Portuguese Large Rivers (F-MMIP-LR) comprises four metrics: % native lithophilic individuals; % alien individuals; % migrant individuals; and % freshwater native individuals, representing compositional, reproductive, and migratory guilds. The index showed good performance in separating least- and most-disturbed sites. Least-disturbed sites were rated ‘high’ or ‘good’ by F-MMIP-LR, contrasting with no such classification for most-disturbed sites, highlighting index robustness. The three rivers presented a wide range of F-MMIP-LR values across the gradient of ‘bad’ to ‘high’, indicating that, on a large spatial extent, the biological condition was substantially altered. The F-MMIP-LR provides vital information for managers and decision-makers, guiding restoration efforts and strengthening conservation initiatives in line with the WFD
- Lactic acid bacteria: a sustainable solution against phytopathogenic agentsPublication . Saragoça, A.; Canha, H.; Varanda, Carla; Materatski, Patrick; Cordeiro, A.I.; Gama, J.Biological control agents (BCAs) are beneficial living organisms used in plant protection to control pathogens sustainably. Lactic acid bacteria (LAB) have gained attention in biopesticides due to their safety as recognized by the Food and Drug Administration. These bacteria possess antifungal properties, demonstrating inhibitory effects through nutrient competition or the production of antimicrobial metabolites. Numerous Lactobacillus species have shown the ability to inhibit pathogenic microorganisms, primarily through acid production. The organic acids secreted by LAB reduce the pH of the medium, creating a hostile environment for microorganisms. These organic acids are a primary inhibition mechanism of LAB. This article reviews several studies on LAB as BCAs, focusing on their inhibition modes. Additionally, it discusses the limitations and future challenges of using LAB to control phytopathogens for sustainable agriculture.
- Fluctuations in Mediterranean Diet adherence pre- and post-pandemic : a study of portuguese cohorts 2019–2024Publication . Andrade, Vanda; Pinto, PaulaBackground/Objectives: The Mediterranean Diet (MD) is a lifestyle offering numerous health benefits. Nevertheless, the adherence to the MD is moderate even in Mediterranean countries. While sociodemographic factors influence MD adherence, additional impacts occurred due to the COVID-19 pandemic. This cross-sectional longitudinal study with three cohorts of Portuguese adults analyzes MD adherence before, during, and after the COVID-19 pandemic, and explores the effect of sociodemographic variables. Methods: Sociodemographic factors, lifestyle habits, and MD adherence were assessed in the years 2019, 2021, and 2024 with an online self-filled questionnaire. MD adherence was measured with the Mediterranean Diet Adherence Screener (MEDAS). Results: MEDAS score increased significantly (p < 0.05) from 2019 to 2021 (6.2 ± 0.7 to 7.7 ± 0.1), followed by a significant (p < 0.05) decrease in 2024 (7.2 ± 0.1) relative to 2019, which was more pronounced in participants with higher income. Accordingly, a trend in healthier
- Local factors have a greater influence on the abundance of alfalfa weevil and its larval parasitoids than landscape complexity in heterogeneous landscapesPublication . Levi‑Mourao, A.; Meseguer, R.; Madeira, Filipe; Martinez‑Casasnovas, J.A.; Costamagna, A.C.; Pons, X.Context The alfalfa weevil Hypera postica Gyllenhal (Coleoptera: Curculionidae) is one of the most destructive pests of alfalfa worldwide. Both local and landscape-scale factors can significantly infuence crop pests, natural enemies, and the efectiveness of biological control services, but the relative infuence of these factors is unclear. Objectives We investigated the infuence of the local variables and surrounding landscape composition and configuration on the abundance of alfalfa weevil, and on the abundance and parasitism rates of its larval parasitoids, Bathyplectes spp. Methods We sampled 65 commercial alfalfa fields along the Ebro Basin, Spain, over a period of 3 years, recording the field characteristics and landscape structure at three buffer radii of 250, 500 and 1000 m from the center of each field. Results The abundance of weevil larvae was positively associated with the field perimeter and with the uncut alfalfa surrounding the pipes of the sprinkler irrigation system, but only one configuration variable was positively correlated: the alfalfa edge density. No local characteristics or landscape structures were associated with the abundance of adult weevils. The abundance of Bathyplectes spp. adults was positively associated to local factors such as the densities of alfalfa weevils and aphids. Few landscape structure variables, such as alfalfa edge density and Simpson’s Diversity Index, had explanatory value only at 250 m buffer radius. The rate of larval parasitism was affected by local variables, such as alfalfa weevil abundance and field age. Conclusion Our results provide, for the first time in the Mediterranean region and Europe, evidence of the relative importance of landscape structure and local factors on the abundance of the alfalfa weevil and its larval parasitoids, Bathyplectes spp. The strongest infuences were based on local characteristics.
- Bisifusarium lunatum causing cladode soft rot in pear cactus (Nopalea cochenillifera) in BrazilPublication . Xavier, L.M.S.; Farias, O.R.; Barbosa, P.R.R.; Varanda, Carla; Materatski, P.; Oliveira, V.S.; Porcino, M.M.; Barros, A.P.; Silva, H.F.; Batista, F.R.C.; Correia, K.C.; Nascimento, L.C.Cactus pear variety Miuda (Nopalea cochenillifera L. Salm-Dyck) is an important crop for the Northeast region of Brazil, composing one of the main sources of animal feed. By April 2021, cladode rot caused death of several cactus pear plants in a production area located in Itaporanga, Paraíba State, Brazil (7°21'55.35'S, 38°11'38.68'W). The infected cladodes showed brown circular necrotic spots and soft rot with perforations that extended throughout the cladode, followed by tipping over and death of the infected plants. The incidence of the disease ranged from 10 to 30% of the plants. Bisifusarium strains were isolated and cultured on potato dextrose agar (PDA) and synthetic nutrient-poor agar (SNA). The colonies were purple in color on PDA. On SNA, macroconidia (n = 100) were abundant, hyaline, slightly falcate, and three-septate, measuring 11.0 to 23.1 × 2.3 to 4.1 µm. Microconidia (n = 100) were oval and generally aseptate, measuring 4.1 to 8.7 × 2.3 to 3.0 µm. Conidiogenic cells formed into short monophialides. Chlamydospores were not observed. According to these morphological features, the pathogen was initially identified as Bisifusarium lunatum (Gryzenhout et al. 2017). For further confirmation of the identification, the partial sequences of translation elongation factor 1-alpha (TEF1-a) and the second largest subunit of RNA polymerase II (RPB2) genes were sequenced for a representative isolate (CMA 34; GenBank accession nos. OR536502 for TEF1-a and OR553509 for RPB2) and compared with other Bisifusarium species from the GenBank database. Subsequently, it was subjected to a phylogenetic analysis of maximum likelihood, including previously published sequences. According to BLAST searches, the TEF1-a and RPB2 sequences were 99% (637/640 nt) and 100% (312/312 nt) similar to B. lunatum (COUFAL0213: TEF1-a [MK640219] and RPB2 [MK301291]), respectively. The isolate was also clustered in a clade containing the ex-type of B. lunatum with 100% support (SH-aLRT and UFboot), being confidently assigned to this species. The pathogenicity test was performed as described by Medeiros et al. (2015) by using healthy 2-month-old cactus pear seedlings (n = 10) cultivated in a greenhouse. Sterile toothpicks were distributed over colonies of the representative isolate grown on PDA at 25 ± 2°C for 7 days. Seedling cladodes were stuck with the toothpicks, moistened with sterile water, and covered with transparent plastic bags for 24 h, thus simulating a humid chamber. Following 3 months, all control plants (stuck with sterile toothpicks) remained healthy, whereas those inoculated with the representative isolate exhibited rot symptoms. This test was performed two times. B. lunatum was reisolated from symptomatic cladodes and identified as previously described, thus fulfilling Koch’s postulates. To our best knowledge, this is the first report of B. lunatum causing soft rot on N. cochenillifera in Brazil. Besides N. cochenillifera, this species was also reported on Opuntia ficus-indica in India (Gryzenhout et al. 2017), which raises concern regarding its ability to infect other forage sources for cattle feed in Brazilian semiarid regions. The present study highlights that the precise identification of B. lunatum is a key factor to adjust control strategies and management of the disease to prevent the spread of this disease to other crops.
- Nutritive value and condensed tannins of tree legumes in silvopasture systemsPublication . Silva, I.A.G.; Dubeux Jr., J.C.B.; Souza, Carla G.; Moreno, M.R.; Santos, M.V.F.; Apolinário, V.X.O.; Mello, A.C.L.; Cunha, M.V.; Muir, J.P.; Junior, M.A.L.Introducing legumes into C4-dominated tropical pastures, may enhance their sustainability but has some pasture management constraints. One potential alternative is using arboreal legumes, but several of these species have relatively high condensed tannin (CT) concentrations, which negatively impact forage quality. There is limited knowledge, however, on how arboreal legume leaf CT content varies over the year and how this might impact forage quality. The objective of this 2 year study was to assess the seasonal variation of CT and nutritive value for ruminants of the tropical tree legumes gliricidia [Gliricidia sepium (Jacq.) Kunth ex. Walp.] and mimosa (Mimosa caesalpiniifolia Benth). The research was carried out in the sub-humid tropical region of Brazil on well-established pastures in which either legume was present with signalgrass (Urochloa decumbens Stapf.). We determined CT and nitrogen concentrations, in vitro digestible organic matter (IVDOM), and leaf δ13C and δ15N from January to October of 2017 and 2018. All parameters were afected (P< 0.05) by the interaction between legume species and sampling time, with generally higher leaf CT content for mimosa than gliricidia, and both were reduced at the start of the dry season, although much more drastically for mimosa. The IVDOM was strongly afected by CT content and increased at the start of the dry season, coincidentally when C4 grass forage quality typically decreased. There is a marked species efect, with CT from gliricidia impacting IVDOM more than the same CT content from mimosa. While N concentration from mimosa also increased at the start of the dry season, that for gliricidia did not vary over the year. We conclude that although these arboreal legumes have relatively high CT contents, these reduce during the dry season when CT concentrations coinciding with a reduced forage quality as the protein content for C4 grasses is usually inadequate in this season.
- Utilidad del enriquecimiento ambiental en las interacciones y caudofagia en cerdosPublication . Araújo, J.P.; Lopes, I.F.; Cerqueira, J.L.; Machado, I.A.; Vicente, António; Almeida, J.P.El desarrollo de comportamientos anormales como la caudofagia en los cerdos es un serio desafío del bienestar y económico de la moderna producción, motivada por factores de riesgo multifactoriales. El enriquecimiento ambiental y el uso de manipulables es una medida fundamental para contribuir para disminuir las interacciones con las colas y consecuentemente la reducción de la caudofagia.