Browsing by Author "Sousa-Santos, Carla"
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- Aeromonas spp. Prevalence, virulence, and antimicrobial resistance in an ex situ program for tThreatened freshwater fish—A pilot study with protective measuresPublication . Grilo, Miguel; Amaro, Guadalupe; Chambel, Lélia; Marques, Carolina S.; Marques, Tiago A.; Gil, Fátima; Sousa-Santos, Carla; Robalo, Joana; Oliveira, ManuelaEx situ breeding programs are important conservation tools for endangered freshwater fish. However, developing husbandry techniques that decrease the likelihood of disease, antimicrobial resistance, and virulence determinants acquisition during this process is challenging. In this pilot study, we conducted a captivity experiment with Portuguese nase (Iberochondrostoma lusitanicum), a critically endangered leuciscid species, to investigate the influence of simple protective measures (i.e., material disinfection protocols and animal handling with gloves) on the dynamics of a potential pathogenic genus, Aeromonas, as well as its virulence profiles and antimicrobial resistance signatures. Our findings show that antimicrobial resistance in Aeromonas spp. collected from I. lusitanicum significantly increased during the extent of the assay (5 weeks), with all isolates collected at the end of the study classified as multidrug-resistant. Additionally, humans handling fishes without protective measures were colonized by Aeromonas spp. The use of protective measures suggested a decreasing trend in Aeromonas spp. prevalence in I. lusitanicum, while bacterial isolates displayed significantly lower virulence index values when virulence phenotypical expression was tested at 22 °C. Despite this study representing an initial trial, which needs support from further research, protective measures tested are considered a simple tool to be applied in ex situ breeding programs for aquatic animals worldwide. Furthermore, current results raise concern regarding antimicrobial resistance amplification and zoonotic transmission of Aeromonas spp. in aquatic ex situ programs.
- Assessment of male reproductive traits in endangered leuciscids from the Iberian Peninsula: First attempts to store gametes both at short- and long-termPublication . Hernández-Rodríguez, Ana; Sousa-Santos, Carla; Gil, Fátima; Cabrita, Elsa; Guerreiro, Pedro M; Gallego, VictorDuring the spring of 2022, several endangered leuciscid species (Anaecypris hispanica, Squalius aradensis, Anachondrostoma Occidentale, and Iberochondrostoma lusitanicum) were sampled both at the Vasco da Gama aquarium facilities and in some rivers of the Algarve region, Portugal. Sperm samples were extracted by gentle abdominal pressure and sperm motion parameters were assessed for the frst time in four species, using a computerized analysis system. The results obtained showed that spermatozoa kinetic patterns were similar for all 4 species, with high motility and velocity values after the sperm activation time and with a marked decrease after 20. On the other hand, sperm longevity was highly variable between species, with short longevities (around 40 s) for A. hispanica and S. aradensis, and longer ex situ breeding programs that are being developed for these four endangered species
- Climatic alterations influence bacterial growth, biofilm production and antimicrobial resistance profiles in aeromonas spp.Publication . Grilo, Miguel L.; Pereira, Ana; Sousa-Santos, Carla; Robalo, Joana; Oliveira, ManuelaClimate change is expected to create environmental disruptions that will impact a wide array of biota. Projections for freshwater ecosystems include severe alterations with gradients across geographical areas. Life traits in bacteria are modulated by environmental parameters, but there is still uncertainty regarding bacterial responses to changes caused by climatic alterations. In this study, we used a river water microcosm model to evaluate how Aeromonas spp., an important pathogenic and zoonotic genus ubiquitary in aquatic ecosystems, responds to environmental variations of temperature and pH as expected by future projections. Namely, we evaluated bacterial growth, biofilm production and antimicrobial resistance profiles of Aeromonas species in pure and mixed cultures. Biofilm production was significantly influenced by temperature and culture, while temperature and pH affected bacterial growth. Reversion of antimicrobial susceptibility status occurred in the majority of strains and tested antimicrobial compounds, with several combinations of temperature and pH contributing to this effect. Current results highlight the consequences that bacterial genus such as Aeromonas will experience with climatic alterations, specifically how their proliferation and virulence and phenotypic resistance expression will be modulated. Such information is fundamental to predict and prevent future outbreaks and deleterious effects that these bacterial species might have in human and animal populations.
- Descripción de dos especies nuevas del género Squalius Bonaparte, 1837 (Actinopterygii, Leuciscidae) en la Península IbéricaPublication . Doadrio, Ignacio; Sousa-Santos, Carla; Perea, SilviaTwo new species, Squalius gaditanus sp. nov. and Squalius tartessicus sp. nov. are described on the basis of morphological and genetic traits. Squalius gaditanus is restricted to the Barbate, Jara and Miel drainages in the province of Cádiz (Southern Spain). Squalius gaditanus sp. nov. can be distinguished from other Squalius species from the Iberian Peninsula through a combination of morphometric, meristic and genetic characters: 36-40 (χ = 38) pored scales on the lateral line; 6-7 (χ = 6.7) scales above the lateral line; 2-3 (χ = 2.8) scales below the lateral line; vertebrae 37-39 (χ = 38); second infraorbital bone narrower than the third in adults; maxilla with reduced pointed anterior process; posterior process of the maxilla long and thin; lower branch of the pharyngeal bone short and robust; pharyngeal plate of basioccipital rounded and two autapomorphies in the mitochondrial cytochrome b gene. Squalius tartessicus sp. nov. inhabits the Almargem, Gilão, Odiel, Guadiana, Guadalquivir, Guadalete, Guadalhorce, Velez, Guadalfeo and Segura drainages in the southern part of the Iberian Peninsula. Squalius tartessicus sp. nov. can be differentiated from other Squalius species from the Iberian Peninsula through a set of morphometric, meristic and genetic traits: 37-41(χ = 38.8) pored scales on the lateral line; 6-7 (χ = 7) scales above the lateral line; 2-3 (χ = 2.9) scales below the lateral line; 37-39 (χ = 38) number of vertebrae; infraorbital bones unusually wide in adults; maxilla with discernable pointed anterior process; posterior process of the maxilla long and thin; lower branch of the pharyngeal bone short and robust; pharyngeal plate of basioccipital triangular in shape; posterior lamina of cleithrum expanding posteriorly.
- The future of biotic indices in the ecogenomic era: Integrating (e)DNA metabarcoding in biological assessment of aquatic ecosystemsPublication . Pawlowski, Jan; Kelly-Quinn, Mary; Altermatt, Florian; Apothéloz-Perret-Gentil, Laure; Beja, Pedro; Boggero, Angela; Borja, Angel; Bouchez, Agnès; Cordier, Tristan; Domaizon, Isabelle; Feio, Maria Joao; Filipe, Ana Filipa; Fornaroli, Riccardo; Graf, Wolfram; Herder, Jelger; van der Hoorn, Berry; Iwan Jones, J.; Sagova-Mareckova, Marketa; Moritz, Christian; Barquín, Jose; Piggott, Jeremy J.; Pinna, Maurizio; Rimet, Frederic; Rinkevich, Buki; Sousa-Santos, Carla; Specchia, Valeria; Trobajo, Rosa; Vasselon, Valentin; Vitecek, Simon; Zimmerman, Jonas; Weigand, Alexander; Leese, Florian; Kahlert, MariaThe bioassessment of aquatic ecosystems is currently based on various biotic indices that use the occurrence and/or abundance of selected taxonomic groups to define ecological status. These conventional indices have some limitations, often related to difficulties in morphological identification of bioindicator taxa. Recent development of DNA barcoding and metabarcoding could potentially alleviate some of these limitations, by using DNA sequences instead of morphology to identify organisms and to characterize a given ecosystem. In this paper, we review the structure of conventional biotic indices, and we present the results of pilot metabarcoding studies using environmental DNA to infer biotic indices. We discuss the main advantages and pitfalls of metabarcoding approaches to assess parameters such as richness, abundance, taxonomic composition and species ecological values, to be used for calculation of biotic indices. We present some future developments to fully exploit the potential of metabarcoding data and improve the accuracy and precision of their analysis. We also propose some recommendations for the future integration of DNA metabarcoding to routine biomonitoring programs.