RESUMO
Length-mass relationships and linear regressions are given for otolith size (length and height) and standard length (LS ) of certain mesopelagic fishes (Myctophidae, Paralepididae, Phosichthyidae and Stomiidae) living in the central Mediterranean Sea. The length-mass relationship showed isometric growth in six species, whereas linear regressions of LS and otolith size fit the data well for all species. These equations represent a useful tool for dietary studies on Mediterranean marine predators.
Assuntos
Tamanho Corporal , Peixes , Membrana dos Otólitos/anatomia & histologia , Animais , Modelos Lineares , Mar MediterrâneoRESUMO
In recent years, a growing body of literature on seafloor macro-litter has been produced worldwide. However, the spatial coverage of these studies is still limited and highly unbalanced, resulting in considerable knowledge gaps in some regions. To address this lack of information in Oceania, we extracted data from the Citizen Science project Dive Against Debris® to characterize marine debris collected by volunteer scuba divers on the coastal seafloor. Overall, the average litter density was 58.22 items/100m2, with plastics accounting for approximately 50 % of the total abundance and Single Use Plastics accounting for nearly 17 %. Notably, 36 % of the total litter abundance consisted of lost Fishing Gear including fishing lines, sinkers, baits and hooks as the most abundant debris items. To reduce lost fishing gear, clean-up initiatives by divers along with management actions such as education programs for fishermen, gear restrictions and the identification of designated fishing sites are recommended.
Assuntos
Ciência do Cidadão , Mergulho , Humanos , Monitoramento Ambiental/métodos , Resíduos/análise , PlásticosRESUMO
The diet of pearly razorfish Xyrichtys novacula, caught monthly along the shores of the Island of Lampedusa, appeared to be mainly composed of crustaceans, followed by colonial ascidians, molluscs and polychaetes. Among prey, sand dwellers and phanerogam-associated species were recorded. In winter months, the diet was characterized by a small number of prey items, dominated by colonial ascidians, while in spring and summer a wider prey array was recorded. Dietary indices show that X. novacula do not strictly exploit benthic prey but also pelagic organisms, such as copepods. This feeding behaviour reached its peak in March and October, when the abundance of primary consumers was at its highest after phytoplankton blooms. Furthermore, X. novacula caught prey organisms according to their availability and seasonal patterns during their life cycles, irrespective of fish size.
Assuntos
Dieta , Perciformes/fisiologia , Comportamento Predatório , Animais , Conteúdo Gastrointestinal , Estações do AnoRESUMO
In this work 437 fish samples of species belonging to the families Myctophidae (Electrona risso and Diaphus metopoclampus) and Phosichthyidae (Vinciguerria attenuata) were examined for the presence of Anisakidae larvae. The study was performed with fishes in the central Mediterranean Sea, particularly in the Strait of Sicily and in the Strait of Messina. The visual inspection and chloro-peptic analysis revealed the presence of nematode parasites with prevalence values between 2.9% in Electrona risso samples and 5.4% in Vinciguerria attenuata samples. A positive correlation was found between standard length (SL) and prevalence of infestation in D. metopoclampus samples (p<0.05). The larvae examined were morphologically ascribed, at genus level, to Anisakis morphotypes I and II and molecularly identified as Anisakis pegreffii, Anisakis ziphidarum and Anisakis physeteris, in 67%, 9% and 24% of the fish samples examined. Overall, A. pegreffii and A. ziphidarum larvae were isolated in 14 and 2 specimens of D. metopoclampus respectively, A. physeteris larvae were found in 3 E. risso and 2 V. attenuata. A positive correlation was found between standard length and prevalence of infestation in D. metopoclampus samples (p<0.05). First information is provided on the presence of Anisakis spp. larvae of the myctophid fish species E. risso, D. metopoclampus and V. attenuata from the Central Mediterranean. It is also confirmed the role of lanternfishes (Myctophidae) as paratenic hosts for Anisakis spp.
Assuntos
Anisaquíase/veterinária , Anisakis/isolamento & purificação , Doenças dos Peixes/epidemiologia , Doenças dos Peixes/parasitologia , Peixes , Animais , Anisaquíase/epidemiologia , Anisaquíase/parasitologia , Anisakis/classificação , Itália/epidemiologia , Larva , Mar Mediterrâneo/epidemiologia , PrevalênciaRESUMO
Ammonium- and Fe(II)-rich fluid flows, known from deep-sea hydrothermal systems, have been extensively studied in the last decades and are considered as sites with high microbial diversity and activity. Their shallow-submarine counterparts, despite their easier accessibility, have so far been under-investigated, and as a consequence, much less is known about microbial communities inhabiting these ecosystems. A field of shallow expulsion of hydrothermal fluids has been discovered at depths of 170-400 meters off the base of the Basiluzzo Islet (Aeolian Volcanic Archipelago, Southern Tyrrhenian Sea). This area consists predominantly of both actively diffusing and inactive 1-3 meters-high structures in the form of vertical pinnacles, steeples and mounds covered by a thick orange to brown crust deposits hosting rich benthic fauna. Integrated morphological, mineralogical, and geochemical analyses revealed that, above all, these crusts are formed by ferrihydrite-type Fe3+ oxyhydroxides. Two cruises in 2013 allowed us to monitor and sampled this novel ecosystem, certainly interesting in terms of shallow-water iron-rich site. The main objective of this work was to characterize the composition of extant communities of iron microbial mats in relation to the environmental setting and the observed patterns of macrofaunal colonization. We demonstrated that iron-rich deposits contain complex and stratified microbial communities with a high proportion of prokaryotes akin to ammonium- and iron-oxidizing chemoautotrophs, belonging to Thaumarchaeota, Nitrospira, and Zetaproteobacteria. Colonizers of iron-rich mounds, while composed of the common macrobenthic grazers, predators, filter-feeders, and tube-dwellers with no representatives of vent endemic fauna, differed from the surrounding populations. Thus, it is very likely that reduced electron donors (Fe2+ and NH4+ ) are important energy sources in supporting primary production in microbial mats, which form a habitat-specific trophic base of the whole Basiluzzo hydrothermal ecosystem, including macrobenthic fauna.
Assuntos
Compostos de Amônio/metabolismo , Archaea/metabolismo , Bactérias/metabolismo , Ecossistema , Compostos Ferrosos/metabolismo , Fontes Hidrotermais/microbiologia , Ferro/metabolismo , Crescimento Quimioautotrófico , Ilhas do Mediterrâneo , Erupções VulcânicasRESUMO
BACKGROUND: The number of patients treated for neoplasms of the oral cavity (by surgery and/or radiotherapy) requiring prosthesis rehabilitation using osteointegrated implants is increasing greatly. The objective of this research is to examine the correlation between prosthesis rehabilitation using osteointegrated implants, radiotherapy and the use of hyperbaric oxygen treatment in order to reduce the risk of osteoradionecrosis. METHODS: Research was carried out on 13 patients with 58 implants. The patients were divided into three sample groups: group A patients underwent radiotherapy (10 implants), group B patients did not undergo radiotherapy (29 implants) and group C patients first underwent radiotherapy and then hyperbaric oxygen treatment (19 implants). The group C patients first underwent hyperbaric oxygen treatment at 2.5 atmospheres. The osteointegrated implants were then applied and hyperbaric oxygen treatment was carried out again over 20-30 postoperative sittings without any other treatment between the sittings. The whole test period lasted 24 months. RESULTS: Only two implants were lost out of the 58 implants and they were in the group that had undergone radiotherapy. CONCLUSIONS: The results show how pre and postoperative hyperbaric oxygen treatment improves the success rate of osteointegrated implants in mandibular areas that had previously undergone radiotherapy. Moreover, the stability of the prostheses that are fixed to the implants is greatly improved compared to conventional methods.