This study evaluated the dietary effects of an ultrasound-assisted extract of Origanum vulgare on the growth, antioxidant and immune responses (serum and mucosal) and resistance of zebrafish (Danio rerio) against Aeromonas hydrophila. Four hundred and forty adult zebrafish were distributed into 12 tanks and fed 4 experimental diets including 0% (control), 0.5% (M1), 1% (M2) and 2% (M3) of the extract per kg⁻¹ diet for eight weeks. Fish were then challenged with A. hydrophila and mortality was recorded for 10 days. Results revealed that the extract exerted potent effects on growth parameters of weight gain and specific growth rate. The feed conversion ratio was significantly lower in fish fed extract-incorporated diets. O. vulgare extract improved antioxidant and immune responses, resulting in less sensitivity to oxidative stress and a higher survival rate when challenged with A. hydrophila. Overall, the greatest effects were observed in individuals with 1% dietary inclusion of the extract. These results suggest that the extract from the plant Origanum vulgare possesses a great potential to be used in the aquaculture industry and that zebrafish is an appropriate model for nutrition studies.

Striped venus (Chamelea gallina) is one of the most important fish resources on the west coast of the Adriatic Sea. Recently, there has been a widespread die-off of C. gallina populations in Friuli-Venezia Giulia (northern Adriatic Sea, Italy), probably due to unfavorable climatic events. Overall, wild populations have become increasingly rare due to many factors affecting the ecological balance of the species. In this study, the available literature was reviewed to determine the current state of knowledge on the biology, ecology, fisheries, and status of C. gallina populations with reference to populations in Friuli-Venezia Giulia. However, few data are available in terms of peer-reviewed articles; much of it can be found in the gray literature (e.g., project reports, ministerial reports, institutional websites, etc.). However, a critical review of the sources reveals that the species is as endangered as the habitats it inhabits. As a result, conservation and restoration efforts have been undertaken to date as part of some larger project to protect the species. Therefore, considering the ecological and economic importance of this species, the results of the new studies will be useful for the scientific community and will be a key element in the conservation of this species.

The replacement of fish oil with refined coconut oil in the diet of large rainbow trout (Oncorhynchus mykiss)