Among a set of wild-type strains of Euplotes nobilii, every one derived asexually from one specimen isolated from Terra Nova Bay (Ross Sea, Antarctica), two were found to be representative of different mating types mutually capable of inducing each other to form mating pairs through pheromones constitutively secreted into the extracellular environment. Pheromones of strain AC-1 were purified to homogeneity and shown to be represented by two distinct proteins, that were denoted En-1 and En-2. En-1, secreted in amounts three-fold greater than En-2, was determined to have a molecular weight of 5617 and an asparagine at the N-terminus of its amino acid sequence, while En-2 has a molecular weight of 6290 and bears an asparctic acid at its N-terminus. The fact that En-1 and En-2 are coreleased by genetically identical cells of the same strain was taken to imply that they carry a heterozygotic combination of allelic pheromone genes and that these genes are regulated by relationships of co-dominance.

In mid Adriatic Sea the common sea snail is the habitual snail eaten, but over the years fishermen started to capture also the long sea snail, a possible alternative for human consumption. This study aims to compare the quality traits of the edible fraction in the common and long sea snails. In this study, common and long sea snail samples were provided by fishermen in November 2018 and March 2019. Total weight (meat and shell), fractions of meat and shell (after having extracted the edible part), fatty acid, elements in meat, and calcium content in shells were determined. Meat quality traits showed high nutritional value without significant differences between the two species. The fatty acid profile showed n3/n6 ratio significantly different both considering the season of sampling (November: 4.1; March: 2.38) and the species of sea snail (common: 4.98; long: 2.86). The long species showed a higher yield in the total body and calcium content concentrations. However, the long sea snail showed 50% lower meat yield compared with the common sea snail. In conclusion, the long sea snail can be used as an alternative to the common sea snail for human consumption.

Proximate composition and fatty acid profile of raw cupped oysters (RA) were compared to conspecific submitted to two different cooking preparations (SA: cooking using extra virgin olive oil in a pan; GR: "gratin"). Moister content was significantly higher in RA (81.7%) with respect to SA (81.1%) and GR (81%). Protein rate significantly decreased from RA (8.8%) to SA (8.3%) and GR (8.4%). Lipids significantly increased in the two cooked GR (2.8%) and SA (2.7%) with respect to RA (2%). Ashes ranged from GR (1.98%) to RA (2%). In the two cooking methods, 18:0 was significantly higher (GR 6.99% and SA 6.15%) than in the raw oysters (RA 4.87%). C18:1 was largely doubled in GR (14.43%) and SA (13.77%) with respect to RA (6.81%). Among n-3 PUFA, 22:6 showed the highest percentage in all the three samples with a significant decrease passing from RA (21.39%) to SA (18.45%) and GR (17.95%). 20:5n-3 had the highest content in RA (17.53%) and significantly decreases in SA (14.09%) and GR (14.54%). Considering the trend of n-3 PUFA and n-6 PUFA, the n-3/n-6 ratio significantly decreased from RA (5.33) to SA (3.58) and GR (3.29). Although proximate composition and fatty acid profile changed after the cooking process, as consequence of the heat treatment and extra virgin olive oil added to the plates, the culinary preparations did not negatively compromise the quality traits of the cooked and gratin oysters.

Effects of administration of krill meal and synthetic astaxanthin during the finisher phase of the fattening cycle of rainbow trout on flesh pigmentation and quality traits were studied. The inclusion of krill meal increased the body weight and size and decreased the peri-visceral fat and visceral weight indices.

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