Flesh qualitative traits of tub gurnard (Chelidonichthys lucerna L.), a promising species candidate for aquaculture, captured in the middle Adriatic Sea in different seasons

The quality traits of the fillets from tub gurnard (Chelidonichthys lucerna L.) fished in the mid-Adriatic Sea were investigated. Forty fishes per season were sampled to evaluate the proximate composition, cholesterol content and fatty acid profile of fillets. Seasons significantly affected the quality traits of flesh. The protein content ranged from 19.39% in winter to 19.67% in summer, without significant differences. Lipid content was notably higher in spring (2.28%) and summer (2.32%), compared to autumn (1.72%) and winter (1.31%). Energy content was significantly higher in spring (416.45 kJ/100 g) and summer (417.97 kJ/100 g) compared to autumn (391.35 kJ/100 g) and winter (372.79 kJ/100 g). Saturated fatty acid content was highest in spring (35.88%), whereas monounsaturated acid content was not influenced by season. The n-3 polyunsaturated fatty acid content exceeded 37% of total fatty acid content during summer. The n-6/n-3 ratio remained favourably low across all seasons (from 0.16 to 0.18), with a slight significant increase in autumn (0.31). In conclusion, this study indicates that the flesh of tub gurnard has high nutritional value year-round, with the best results (in terms of n-3 polyunsaturated fatty acids) being obtained in summer

Tub gurnard Chelidonichthys lucerna L.: a new fish species suitable for farming? First answers evaluating the growth of juveniles reared at different stocking densities, welfare and fillet quality

A trial was conducted to evaluate the growth performance and survival of Chelidonichthys lucerna. A total of 13 352 180-days old juveniles (5.5 ± 2 g; 5 ± 1 cm) were reared at two different densities (A-EXP = 68 fish m−3; B-FFA = 15 fish m−3) in eight tanks (four tanks per group) for 360 days. The welfare status and meat quality of fish were evaluated for the A-EXP and B-FFA groups in comparison with wild-caught fishery gurnard (C-WID). The survival rate was high for both A-EXP (79%) and B-FFA (93.5%). B-FFA fish had the highest specific growth rate (1.16 vs. 1.07; P < 0.05), and were heavier than A-EXP fish (321 ± 40 g vs .239 ± 44 g; P < 0.01). Rearing conditions did not affect blood metabolites, except for glucose concentrations, which were higher in C-WID (P < 0.05). The meat quality traits showed that reared groups were fatter (2.8–3.2%) than C-WID (0.94%); total n-3 fatty acids (19.02–19.26%) were lower in reared groups than C-WID (29.99%); and EPA + DHA were similar in all groups (15.1–16.61% vs. 27.99%). Despite the good growth and survival, the final mean weight was below that requested by the market (400–500 g). Future research efforts should focus on reducing the feed conversion rate (3:1)

Suitability of artisanal fishery discards as feed for juvenile tub gurnard (chelidonichthys lucerna L.) reared in sea bottom cages in the mid Adriatic Sea

The suitability of using discards from artisanal fisheries as feed for wild-caught Chelidonichthys lucerna (L.) reared in submerged cages in the Adriatic Sea was investigated. Three-hundred juvenile tub gurnard (72.9 ± 11 g, 18 ± 1 cm) were captured and separated into four circular 35.3 m3 submerged cages. Two stocking densities were used: two cages contained 60 fish each (1.7 fish m-3; CG-L) and two cages contained 90 fish each (2.55 fish m-3; CG-H). Growth performance and survival rates were recorded over a 240 day period during which tub gurnard were fed with a variety non-target fishery discards, including common crab, sardine, Atlantic chub mackerel, anchovy, and salema. The survival rate was approximately 90% in both groups (CG-L = 91% and CG-H = 90%), with final stocking densities of 0.32 kg m-3 and 0.49 kg m-3 for the CG-L and CG-H groups, respectively. There were no significant differences in final mean body weight or length between the CG-L group (206 ± 23 g, 24.6 ± 2 cm) and the CG-H group (215.5 ± 32 g, 24.8 ± 2 cm). The condition index was similar between the two groups (1.38 and 1.42 for CG-L and CG-H, respectively). The feed conversion ratio was high in both the CG-H (2.39) and CG-L (2.32) cages. These results demonstrate that viable growth rates of tub gurnard may be obtained by feeding recycled fishery discards and rearing in cages placed on the seabed, which allows for the natural benthic behavior of this species

Effects of dietary supplementation with krill meal on pigmentation and quality of flesh of rainbow trout (Oncorhynchus mykiss)

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. The astaxanthin diet produced the highest accumulation of total carotenoids in the fillet compared to the krill meal diet: the difference was significant after 15 days of feeding (2.50 vs 2.10 mg/kg) till the end of the trial (5.00 vs 4.80 mg/kg). The same pattern was observed for astaxanthin concentration with the highest values in the fillets of fish fed the astaxanthin diet. Fillet lightness (L*) was not affected by trout diets whereas redness (a*) and yellowness (b*) were significantly higher in fish fed the astaxanthin diet until day 30 of the trial. Hue was not affected by feeding, whereas chroma was significantly higher in the fish fed astaxanthin throughout the trial except on day 45 of sampling. Trout fed the krill meal diet had a paler pink-red colour on the SalmoFan scale than those receiving the astaxanthin diet. No significant differences emerged in proximate composition and cholesterol content of trout in the two groups. The fatty acid profile of the fillets reflected the fatty acids of the diets administered to the trout: eicosapentaenoic, docosahexaenoic and docosapentaenoic acids and total n-3 polyunsaturated fatty acids were significantly higher in the fish fed the krill meal

Effects of rearing density on rainbow trout welfare, determined by plasmatic and tissue parameters

The work aimed to determine the welfare status of rainbow trout (50±15 g), intensively reared to commercial size in twoconcrete raceways (V1, V2) at different stocking densities, to reach final load of 40 kg/m3 and 20 kg/m3, respectively.Throughout the out-phase, plasma parameters and hepatic glycogen content were determined every three months andcompared with those of rainbow trout of the same age and mean weight, reared extensively (VE). At the end of the trialsignificant differences of the monitored parameters were found between rainbow trout reared in raceways (V1, V2) andthose held in the reservoir (VE). Plasma triglycerids, total cholesterol and alkaline phosphatase in fish reared intensivelywere significantly different from fish reared in extensive conditions. The highest levels of these parameters in V1 andV2 could be justified mostly by the administration of balanced feeding and consequent modifications of energeticmetabolism and in small part to the high density of the intensive rearing conditions. Transaminases (AST, ALT) increasedin V1 and V2 only at the first sampling. Afterwards, the activity of these two enzymes returned to the normal range atthe subsequent assays, suggesting a capacity of the rainbow trout to adapt to the severe conditions of confinement, typicalof out-basins. No significant differences among groups were observed for total protein, glucose, CK and LDH. A similarsituation was also shown for liver glycogen content

Bone Marrow Foot Oedema in Adolescents: The Role of Vitamin D

BACKGROUND: Bone marrow oedema (BMO) in children/adolescents is a rare clinical condition without an etiologic cause. It is associated with typical increased signal intensity on T2-weighted magnetic resonance images (MRI) and an increase in bone turnover in which vitamin D plays a pivotal role. No treatment guidelines for these young patients are to date available. METHODS: We performed a retrospective study in a pediatric setting of 13 patients with diagnosis of primary BMO of the foot on the basis of clinical and radiological findings. Data collection included sex, age, patient history, symptoms at presentation, clinical examination, laboratory bone turnover markers, vitamin D levels, MRI, treatment, and outcome. RESULTS: Vitamin D deficiency or insufficiency was found in 76.9% of cases. All patients were treated with adequate vitamin D daily intake, a short course of analgesic therapy, physical therapy, avoiding detrimental feet and ankle immobilization. All fully recovered in 3-month lag period. CONCLUSIONS: Our data highlight that environmental factors, such as underestimated articular or bone microtraumatisms, as well as joint hyper mobility, in a bone turnover milieu of vitamin D deficiency could be the cause of this clinical conditions. Adequate vitamin D supplementation, associated with physical and analgesic therapy, is crucial in the management of BMO