Publications by authors named "Rodrigo O A Ozorio"

Article Synopsis
  • The study examines how short-term swimming affects the immune and antioxidant systems in European eels (Anguilla anguilla).
  • Induced swimming led to lower cortisol levels in the plasma and increased activity of certain immune enzymes in the skin mucus, but did not change glucose or lactate levels.
  • Additionally, swimming improved antioxidant status in the liver and muscle, indicating that physical activity can influence health markers in farmed fish.
View Article and Find Full Text PDF

Swimming has relevant physiological changes in farmed fish, although the potential link between swimming and oxidative stress remains poorly studied. We investigated the effects of different medium-term moderate swimming conditions for 6 h on the antioxidant status of gilthead seabream (Sparus aurata), analyzing the activity of enzymes related to oxidative stress in the liver and skeletal red and white muscle. Forty fish were induced to swim individually with the following conditions: steady low (SL, 0.

View Article and Find Full Text PDF

Aerobic swimming exercise in fish has been shown to improve robustness of some species. However, the optimal conditions to be applied and the mechanisms underlying remain unknown. We investigated the effects of 6 h of induced swimming on the immune response of gilthead seabream (Sparus aurata), by analysing markers related to immune status in plasma, skin mucus, gills, heart and head-kidney.

View Article and Find Full Text PDF

A fish trial was carried out to evaluate the combined effects of temperature and dietary lipid level on the body composition, growth performance, and freshness profile of the European seabass (). Fish were kept for 56 days at 20 °C and 24 °C and fed on two diets, with 16% and 20% lipid. At the end of the trial, fish were euthanized at two temperature conditions (0.

View Article and Find Full Text PDF

Cultured fish can be induced to swim, although the suitability and benefits remain to be tested. Sustained swimming exercise (SSE) training and detraining (DET) were applied in juvenile gilthead sea bream (Sparus aurata) and the metabolic rates were investigated. Fish with a total body mass of 80.

View Article and Find Full Text PDF

European seabass (Dicentrarchus labrax) production is often hampered by bacterial infections such as photobacteriosis caused by Photobacterium damselae subsp. piscicida (Phdp). Since diet can impact fish immunity, this work investigated the effect of dietary supplementation of 5% Gracilaria sp.

View Article and Find Full Text PDF

The fatty acid (FA) profile of oysters generally reflects the dietary FA composition. Moreover, incorporation of FA into tissues is modulated by various metabolic factors, and final composition will depend upon the dietary sources, cumulative intake, and oysters' development stage. Thus, the aim of this study was to assess the impact of dietary incorporation of seaweed (SW) Ulva rigida, in replacement of traditional microalgae diet, on the FA composition of Pacific oysters Crassostrea gigas, during broodstock conditioning.

View Article and Find Full Text PDF

In aquaculture, fish may be exposed to sub-optimal rearing conditions, which generate a stress response if full adaptation is not displayed. However, our current knowledge of several coexisting factors that may give rise to a stress response is limited, in particular when both chronic and acute stressors are involved. This study investigated changes in metabolic parameters, oxidative stress and innate immune markers in a rainbow trout () isogenic line exposed to a combination of dietary (electrolyte-imbalanced diet, DEB 700 mEq Kg) and environmental (hypoxia, 4.

View Article and Find Full Text PDF

The current study evaluated the microalgae replacement by dry macroalgae () in the reproductive success and biochemical composition of the Pacific oyster () during broodstock conditioning. Five nutritional regimes were tested: 100% macroalgae (diet 1), 50% macroalgae+50% microalgae (diet 2), 25% macroalgae+75% microalgae (diet 3) and 100% microalgae (diet 4). An unfed group was used as a negative control.

View Article and Find Full Text PDF

Oxygen limitation and dietary imbalances are key aspects influencing feed intake (FI) and growth performance in cultured fish. This study investigated the combined effects of hypoxia and dietary electrolyte balance on the growth performance, body composition and nutrient utilization in a rainbow trout (Oncorhynchus mykiss) isogenic line. Fish were fed ad libitum two experimental diets: electrolyte-balanced or -imbalanced diets (DEB 200 or 700 mEq kg, respectively) and exposed to normoxia or hypoxia (7.

View Article and Find Full Text PDF

Intensive aquaculture practices involve rearing fish at high densities. In these conditions, fish may be exposed to suboptimal dissolved O levels with an increased formation of reactive O species (ROS) in tissues. Seaweeds (SW) contain biologically active substances with efficient antioxidant capacities.

View Article and Find Full Text PDF

Dietary ion content is known to alter the acid-base balance in freshwater fish. The current study investigated the metabolic impact of acid-base disturbances produced by differences in dietary electrolyte balance (DEB) in the meagre (Argyrosomus regius), an euryhaline species. Changes in fish performance, gastric chyme characteristics, pH and ion concentrations in the bloodstream, digestive enzyme activities and metabolic rates were analyzed in meagre fed ad libitum two experimental diets (DEB 200 or DEB 700mEq/kg) differing in the NaCO content for 69days.

View Article and Find Full Text PDF

Aeromonas hydrophila is causing substantial economic losses in world aquaculture. This study determined the tolerance limit (LD50-96h) of A. hydrophila in Arapaima gigas, and also investigated the clinical signs after intradermal inoculation.

View Article and Find Full Text PDF

A 51-day feeding trial was carried out to determine the effects of various dietary levels of brewer's yeast, Saccharomyces cerevisiae, in the growth performance, body composition and nutrient utilization in Nile tilapia, Oreochromis niloticus, juveniles. Fish (7.6 ± 0.

View Article and Find Full Text PDF

The current study investigated the olfactory sensitivity of the blackspot sea bream to amino acids, odorants associated with food detection in fish, and compared the efficacy of two different experimental methods: multi-unit recording from the olfactory nerve and the electro-olfactogram (EOG). Twenty essential amino acids plus L-DOPA evoked clear, concentration-dependent olfactory responses using both methods, with estimated thresholds of 10(-8.5)-10(-6.

View Article and Find Full Text PDF

African catfish (Clarias gariepinus) were fed four isonitrogenous diets (34 % crude protein), each containing one of two lipid (100 or 180 g/kg) and two L-carnitine (15 or 1000 mg/kg) levels. After 81 d of feeding, thirty-two fish (body weight 32 g) from each dietary group were randomly selected, sixteen fish were induced to a 3-h swim (speed of 1.5 body length (BL)/s), while the other sixteen fish were kept under resting condition.

View Article and Find Full Text PDF