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BackgroundThe use of nutritional supplements (NS) among athletes is widespread. However, little is known about the relationship between nutritional adequacy and NS usage. The aims of this study were to evaluate the NS usage and to compare the nutritional intake from food and prevalence of micronutrient inadequacy (PMI) between NS users and non-users.MethodsPortuguese athletes from 13 sports completed an NS usage questionnaire and a semi-quantitative food-frequency questionnaire assessing information over the previous 12 months. The estimated average requirement cut-point method was used to calculate PMI. General linear models were used to compare nutritional intake and NS usage. Chi-squared tests and logistic regression were performed to study, respectively, relationships and associations between PMI and NS usage.ResultsFrom the 244 athletes (66% males, 13–37 years), 64% reported NS usage. After adjustment, NS users showed a higher intake from food (p < 0.05), for at least 1 gender, for energy, and for 7 of the 17 studied nutrients. The highest PMI were seen for vitamins D and E, calcium, folate, and magnesium. After adjustment, NS users, irrespective of gender, reported lower PMI for calcium (OR = 0.28, 95%CI: 0.12–0.65), and female users for magnesium (OR = 0.06, 95%CI: 0.00–0.98).ConclusionAthletes using NS reported a higher nutritional intake from food, and a lower PMI for several nutrients. Perhaps, those who were taking NS were probably the ones who would least benefit from it.

Twelve adolescent athletes underwent, in a crossover-design study, 3 separate 90-min training sessions in the following conditions: no fluid ingestion allowed (NF), ad libitum ingestion of water (W), and ad libitum ingestion of a commercial 8% carbohydrate-electrolyte sports beverage (CSB). After each session athletes performed a set of basketball drills (2-point, 3-point, and free-throw shootout, suicide sprints, and defensive zigzags). Body weight (before and after sessions), rating of perceived exertion (RPE), urine color, and beverage acceptability were determined in each session. Athletes also completed a survey about their knowledge and behaviors regarding hydration and fluid replacement. The percentage of weight loss was significantly higher in NF (2.46% ± 0.87%) than in the other 2 conditions (W, 1.08% ± 0.67%, p = .006; CSB, 0.65% ± 0.62%, p = .001) but also higher in W than CSB (p = .012). RPE was higher in NF (16.8 ± 1.96) than in the W (14.2 ± 1.99, p = .004) and CSB (13.3 ± 2.06, p = .002) trials. Athletes' fluid intake was positively correlated with proper self-reported behaviors (r = .75, p = .005) and knowledge (r = .76, p = .004) about fluid and hydration. In conclusion, fluid restriction during exercise was associated with a greater level of dehydration and increased perceived exertion but had no impact on basketball performance compared with ad libitum drinking of water or a CSB. Athletes with more knowledge about hydration and better self-reported hydration behaviors ingested more fluids during training sessions.

Objective. To determine if acid-etched, cross-linked dentin can be dehydrated without lowering bond strength below that of cross-linked wet-bonded dentin in vitro.Methods. Using extracted human third molars, control acid-etched dentin was bonded with Single Bond Plus, using either the wet-or dry-bonding technique. Experimental acid-etched dentin was treated with 5 mass% grape seed extract (GSE) in different solvents for 1 min before undergoing wet vs dry resin-dentin bonding with Single Bond Plus. Completely demineralized dentin beams were treated with 5% GSE for 0, 1 or 10 min, before measuring stiffness by 3-point flexure. Other completely demineralized beams were treated similarly and then incubated in buffer for 1 week to measure the collagen solubilization by endogenous dentin proteases.Results. 24 h microtensile bond strengths (TBS) in wet and dry controls were 53.5 ± 3.6 and 9.4 ± 1.8 MPa, respectively (p < 0.05). 5% GSE in water gave TBS of 53.7 ± 3.4 and 39.1 ± 9.7 MPa (p < 0.05), respectively, while 5% GSE in ethanol gave TBS of 51.2 ± 2.3 and 35.3 ± 2.0 MPa (p < 0.05). 5% GSE in 5% EtOH/95% water gave wet and dry TBS of 53.0 ± 2.3 and 55.7 ± 5.1 MPa (p > 0.05). Cross-linking demineralized dentin with 5% GSE increased stiffness of dentin and decreased collagen degradation (p < 0.05).

This study evaluated the ability of orange peel fragment (OPF) to act as a functional feedstuff, influencing growth, haematological profile, and antioxidant enzyme activity of Nile tilapia subjected heat/dissolved oxygen-induced stress (HDOIS). A group of 440 male Nile tilapia (31.7 g ± 0.34) was randomly distributed in 40 250-L aquaria (11 fish/tank) and fed five practical diets with graded levels of OPF at 0%, 0.2%, 0.4%, 0.6%, and 0.8% for 70 days. The diets were formulated to contain 30% crude protein and 18 MJ/kg crude energy. After the feeding period, growth performance was evaluated and six fish per treatment were sampled for haematological profile and antioxidant enzyme activity, before and after HDOIS. Then, fish were subjected to HDOIS (32°C/2.3 mg/L dissolved oxygen) for three days and the same haematological profile and antioxidant enzyme activity were determined. There was no effect of OPF on the haematological profile, either before or after HDOIS. The polynomial regression model was used to express the relationship between antioxidant enzymes activity and OPF supplementation level. The maximum activity of superoxide dismutase, catalase, and glutathione peroxidase was reached at 0.66%, 0.63%, and 0.68% of OPF respectively. Results of the present study suggest that a dietary supplementation level of 0.63%-0.68% of orange peel fragment was appropriate to maintain Nile tilapia haematological profile and improve its antioxidant capacity under HDOIS. K E Y W O R D Santioxidant system, orange by-product, orange peel fragment, Oreochromis niloticus, temperature stress

Fish rely on their innate immune responses to cope with the challenging aquatic environment, with antimicrobial peptides (AMPs) being one of the first line of defenses. Piscidins are a group of fish specific AMPs isolated in several species. However, in the European sea bass (Dicentrarchus labrax), the piscidin family remains poorly understood. We identified six different piscidins in sea bass, performed an in-depth molecular characterization and evaluated their antimicrobial activities against several bacterial and parasitic pathogens. Sea bass piscidins present variable amino acid sequences and antimicrobial activities, and can be divided in different sub groups: group 1, formed by piscidins 1 and 4; group 2, constituted by piscidins 2 and 5, and group 3, formed by piscidins 6 and 7. Additionally, we demonstrate that piscidins 1 to 5 possess a broad effect on multiple microorganisms, including mammalian parasites, while piscidins 6 and 7 have poor antibacterial and antiparasitic activities. These results raise questions on the functions of these peptides, particularly piscidins 6 and 7. Considering their limited antimicrobial activity, these piscidins might have other functional roles, but further studies are necessary to better understand what roles might those be.

Nutritional strategies can help fish manage stress, and functional feedstuffs are an interesting nutritional option. Therefore, this study evaluated the potential functional effect of spray-dried plasma (SDP) on Nile tilapia growth performance and the capacity of SDP to improve fish health under cold-induced stress (CIS). A total of 440 fish (12.64 ± 0.64 g) were randomly distributed into 40,250-L aquaria and fed five diets containing graded levels of SDP (0, 16.6, 33.2, 49.7 and 66.3 g kg − 1) for 60 days. The growth performance, villus height:crypt depth ratio, and hematological parameters were analyzed, and the same hematological parameters were then analyzed after 7 days of CIS. Based on the broken-line analysis of the FBW, SGR, RWG and FCR, the optimum dietary level supplementation of SDP was determined to be 49.70, 50.16, 51.83 and 41.83 g kg − 1 diet, respectively. The crypt depth and villus:crypt ratio were positively affected by SDP supplementation. After CIS, hematocrit of fish fed 16.6 g kg − 1 of dietary SDP was significantly lower than fish fed 66.3 g kg − 1 level (P < 0.05). The supplementation level of dietary SDP and the CIS affected the leukocyte, lymphocyte and neutrophil counts. The monocyte count was affected by the dietary SDP supplementation level both before and after CIS (P < 0.05). Total plasma protein concentration in the fish fed 49.7 and 66.3 g kg − 1 SDP were significantly higher than fed 16.6 g kg − 1 SDP after CIS (P < 0.05), and CIS led to a higher Albumin:Globulin ratio (P < 0.05). Dietary SDP supplementation improved the growth performance, intestinal health, hematological profile and CIS resistance of the studied fish. Based on our results, we recommend a dietary supplementation level of 51.83 g kg − 1 SDP for Nile tilapia.

This study evaluated growth performance, hematological parameters, histological liver analysis, and production costs of Nile tilapia fed increasing levels of digestible protein, digestible energy, and choline. Twelve thousand Nile tilapia (148 ± 6.7 g) were randomly distributed into 80 1 m 3 net cages, in a 5 × 2 × 2 factorial design with five digestible protein (DP) levels (24, 26, 28, 30, and 32% DP), two digestible energy (DE) levels (13.4 and 14.65 MJ DE kg −1 diet), and two choline levels (0.0 and 1000 mg kg −1 diet), with four replicates per treatment. Fish fed the higher energy level showed a sparing effect of protein; the higher protein level determined the highest fillet yield. Fish fed diets with 24% DP showed the highest liver lipid, and independently of treatment all analyzed fish showed hepatocyte degeneration. The best benefit cost ratio for whole fish production was achieved with 28% DP/13.4 MJ DE kg −1 , and for fillet production with 30% DP/13.4 MJ DE kg −1. The results of the hematological assay showed alterations in red blood cells, mean corpuscular volume, albumin, Albumin:Globulin ratio, and glucose after size-sorting stress. Overall, these results indicate a lower resistance to stress, mainly for fish fed with no choline and oil supplementation. In this study we determined that the best performance was achieved with DP:DE ratios of 21.45 g MJ −1 (28.74% DP/13.4 MJ DE kg −1) and 18.60 g MJ −1 (27.25% DP/14.65 MJ DE kg −1). The highest fillet yield was obtained with 30% DP, regardless of the dietary energetic level. Sustained homeostasis was observed in this setting, and even though size-sorting stress altered some hematological parameters, they were still within the range recognized as healthy. Choline was not effective in protecting the liver against hepatic steatosis, but was able to buffer some of the negative effects of stress under these rearing conditions. Statement of Relevance: This research has been approved by the Ethics Committee of our Institution. Our team has been working with nutrition and fish health since 2000. According to the NRC (2011), only a few studies have been conducted to estimate the dietary nutrient requirements of farmed fish under intensive culture conditions. Moreover, a number of factors may affect the dietary and nutritional requirements of fish differentially in the laboratory and under intensive culture. For example, climatic conditions may fluctuate widely in the field, directly affecting physiological responses, hence nutritional requirements. Similarly, fish densities are much higher under intensive farming. Establishing the appropriate nutritional requirements in these settings must also consider the trade-off between growth performance and production costs. Based on this, we investigated the effect of different levels of digestible protein and digestible energy on growth performance and hematological responses of the Nile tilapia in a commercial fish farm in Brazil, where fish farmers are known to use diets with excessive levels of crude protein through...