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Senegalese sole is considered a species with high interest for aquaculture diversification in the South of Europe whose production has shown an important increase in recent years. However, broodstock nutrition of this species is still based on a diet of fresh feeds, which poses important sanitary risks, has variable supply and nutritional composition and contributes to the deterioration of water quality. This study was performed to test two new specifically formulated semi-moist diets for Solea senegalensis broodstock: a control diet (CTR) formulated with high quality ingredients and a further supplemented diet (PLUS), fortified with lipids, vitamins and long-chain polyunsaturated fatty acids (LC-PUFA), mainly DHA. Larvae originating from simultaneous spawns of both broodstock groups were reared in the same standard conditions up to 67 days post-hatching (dph) and effects were assessed on early ontogeny (up to first-feeding), larval (up to 17 dph) and juvenile performance. Both diets led to the production of eggs with good viability, hatching rate and fatty acid composition. The fatty acid profile reflected differences in the experimental diets, with eggs from the PLUS group presenting higher levels of both EPA and DHA, although more markedly for EPA. Furthermore, significant differences in the percentage of EPA were maintained until 7 dph, while DHA was only significantly higher in eggs and 0 dph larvae from the PLUS treatment. The expression of enzymes of the LC-PUFA biosynthesis pathway was assessed in parallel and results show that transcript levels of elovl5 and Δ4fad in eggs and newly hatched larvae were affected by broodstock diet and that DHA biosynthesis capacity of Senegalese sole larvae may have been up-regulated at hatching in the CTR treatment. Further nutrient supplementation in the PLUS diet did not enhance larval survival and performance and larvae originating from this treatment were significantly smaller than their CTR counterparts at hatching and 3 dph and had lower growth up to 17 dph, probably reflecting variations in egg size between batches. However, after metamorphosis, post-larvae from the PLUS treatment quickly caught-up and after complete weaning were significantly larger than juveniles originating from the CTR broodstock. Furthermore, juveniles from the PLUS treatment had a much lower incidence of tail fin deformity. These results were surprising and should be further investigated as, although we cannot exclude a genetic effect, the results could also indicate a nutritional programming effect of broodstock diet in sole juvenile growth and quality. In addition, the results suggest that Senegalese sole larvae are capable of regulating DHA biosynthesis as early as at hatching to counterbalance lower levels of DHA in eggs. Finally, we demonstrate that the current feeding protocol of sole broodstock can be replaced by a safer formulated semi moist diet with good results.

Summary Background & aims Cachexia is a multiorganic syndrome associated with cancer, characterized by body weight loss, muscle and adipose tissue wasting and inflammation, being often associated with anorexia. The aim of the present investigation was to examine the effect of megestrol acetate (MA) in cachectic tumour-bearing animals analyzing changes in muscle proteolysis and in parameters related with quality of life. Methods The effects of MA (100 mg/kg) were tested in cachectic tumour-bearing rats (Yoshida AH-130 ascites hepatoma). Results Administration of MA to tumour-bearing rats resulted in an important reversal of the muscle wasting process, as reflected by individual muscle weights. MA also decreased the rate of protein degradation in incubated isolated skeletal muscles. Real-time PCR analysis revealed that MA treatment resulted in a decrease in ubiquitin, E2 and atrogin-1 mRNA content in muscles, therefore suggesting that the main anti-proteolytic action of the drug may be based on an inhibition of the ATP-ubiquitin-dependent proteolytic system. The drug also improves appetite, weight loss, total physical activity and grip force. Conclusions The results indicate that treatment with megestrol acetate increases appetite, weight loss, physical performance and muscle force in tumour-bearing rats suggesting that MA is a good candidate for muscle wasting treatment.

The preparation of protein hydrolysates from black scabbardfish (Aphanopus carbo) by-products (BSB) was studied as an alternative for the upgrading of this raw material. Different levels of Protamex™ were used in the hydrolysate preparation and the peptides obtained and the lipids present in each of the four fractions obtained after centrifugation of the hydrolysed material were characterized. The nitrogen solubilization achieved was around 83% and degree of hydrolysis (DH) was about 57%. A high proportion of the peptides had molecular weights lower than 1000 Da. The highest percentage of oil remained in the emulsion (50–65%) and the highest percentage of free oil obtained was ca. 36%. The fatty acid profile of lipids present in the BSB and in the different fractions was similar. The triacylglycerols were dominant in all fractions and the highest percentage of phospholipids was detected in the oil from sludge and hydrolysate, followed by the emulsion but they were not present in the free oil. Cholesterol and cholesterol esters were detected in all fractions at low levels. The 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging activity and the reducing power of BSB hydrolysates increased with increasing DH. However, the hydroxyl scavenging activity decreased with DH.