Evaluation of the long-term effects of formaldehyde on the physiology of the Mediterranean mussel, Mytilusgalloprovincialis.

Formalin baths are the most widely used treatment for ectoparasitic fish diseases. Nonetheless, their use in fish cages has been blamed for a number of problems. Although a considerable amount of literature has been produced on the short-term toxic effects of formaldehyde, there is virtually no data on the long-term side effects of the compound on non-target organisms. Therefore, the purpose of this research was to assess the long-term formaldehyde toxicity in Mediterranean mussel, Mytilus galloprovincialis, a common sentinel species that inhabits the area surrounding cage farms. Mussels were kept in a laboratory microenvironment at 20 ± 1 °C for 21 days and exposed to two different formaldehyde concentrations during experimentation: a low dose (L; 40 ppb) based on formaldehyde field measurements in the vicinity of Mediterranean cages, and a high dose (H; 400 ppb) generated by a factor of 10 of the previous dose. A multi-biomarker approach that included antioxidant enzymes such as catalase (CAT) and superoxide dismutase (SOD), lipid peroxidation (MDA), lysosomal stability (NRRT), genotoxicity tests, condition index (CI), and stress on stress (SoS), was used to evaluate the toxicity of formaldehyde on mussels. The results of the selected tests indicate that formaldehyde does not cause chronic toxicity in mussels subjected to commonly measured concentrations in the aquatic environment following formalin bath treatments. Despite being defined as reversible, the stress brought by the high dose used seems to reduce the antioxidant activity of the tested organism. The significance of this research lies in its contribution to understanding the wider ecological effects of formaldehyde exposure. Moreover, the results highlight the need for further research on other non-target marine organisms to fully understand the cumulative effects of formaldehyde on marine ecosystems.

Cryptosporidium and agriculture: A review.

Cryptosporidiosis is a significant contributor to global foodborne and waterborne disease burden. It is a widespread cause of diarrheal diseases that affect humans and animals worldwide. Agricultural environments can become a source of contamination with Cryptosporidium species through faecal material derived from humans and animals. This review aims to report the main findings of scientific research on Cryptosporidium species related to various agricultural sectors, and highlights the risks of cryptosporidiosis in agricultural production, the contamination sources, the importance of animal production in transmission, and the role of farmed animals as hosts of the parasites. Agricultural contamination sources can cause water pollution in groundwater and different surface waters used for drinking, recreational purposes, and irrigation. The application of contaminated manure, faecal sludge management, and irrigation with inadequately treated water are the main concerns associated with foodborne and waterborne cryptosporidiosis related to agricultural activities. The review emphasizes the public health implications of agriculture concerning the transmission risk of Cryptosporidium parasites and the urgent need for a new concept in the agriculture sector. Furthermore, the findings of this review provide valuable information for developing appropriate measures and monitoring strategies to minimize the risk of infection.

Recent Advances in Mycotoxin Determination in Fish Feed Ingredients.

Low-cost plant-based sources used in aquaculture diets are prone to the occurrence of animal feed contaminants, which may in certain conditions affect the quality and safety of aquafeeds. Mycotoxins, a toxic group of small organic molecules produced by fungi, comprise a frequently occurring plant-based feed contaminant in aquafeeds. Mycotoxin contamination can potentially cause significant mortality, reduced productivity, and higher disease susceptibility; thus, its timely detection is crucial to the aquaculture industry. The present review summarizes the methodological advances, developed mainly during the past decade, related to mycotoxin detection in aquafeed ingredients, namely analytical, chromatographic, and immunological methodologies, as well as the use of biosensors and spectroscopic methods which are becoming more prevalent. Rapid and accurate mycotoxin detection is and will continue to be crucial to the food industry, animal production, and the environment, resulting in further improvements and developments in mycotoxin detection techniques.

Molecular cloning of four glutathione peroxidase (GPx) homologs and expression analysis during stress exposure of the marine teleost Sparus aurata.

Glutathione peroxidase (GPx; EC 1.11.1.9) is an important family of enzymes that protects organisms from oxidative damage. Four full-length GPx cDNAs were cloned and characterized by rapid amplification of cDNA ends polymerase chain reaction (RACE-PCR) from the liver of gilthead sea bream (Sparus aurata), an economically important species for Mediterranean aquaculture. Structural and functional annotations were performed for all paralogs, which suggested possible differences in function and subcellular localization. The phylogenetic analysis, based on the amino acid sequences, revealed four groups corresponding to teleostean GPx1a, GPx1b, GPx4a, and GPx4b and three groups for mammalian GPx1, GPx2 and GPx4. The tree topology indicated past duplication events for fish genes, unlike their mammalian homologs. Transcriptional analysis in ten tissues by reverse transcription quantitative polymerase chain reaction (RT-qPCR) evidenced a tissue-specific pattern for each GPx homolog. Fish experimental groups were exposed to stress factors such as fasting and confinement. Relative expression analysis in fish liver demonstrated that GPx1 genes were not regulated by dietary restriction; GPx4b was differentially expressed opposed to regularly fed fish. On the other hand, both GPx1 and GPx4 genes were up-regulated in fish post exposed to confinement, considered as a response to acute stress. The results underline the role of GPx genes as indicators of stress and welfare status in gilthead sea bream aquaculture.