Reduced n-3 highly unsaturated fatty acids dietary content expected with global change reduces the metabolic capacity of the golden grey mullet

Abstract

of haematocrit and plasma osmolality, indicating a stress response at the second and third levels in that group. However, the LD diet caused a massive increase in swimming efficiency. This should improve the capacity of L. aurata to migrate and to forage over a wide area. In turn, these could then compensate for the reduction in growth rate and aerobic metabolism.

Ocean warming combined with lower omega-3 nutritional availability impairs the cardio-respiratory function of a marine fish

“…The LH diet was obtained by replacing the fish oil present in the HH diet with soybean oil. Diets were formulated taking a standard diet as the reference (1.2% EPA+DHA on a dry matter basis), as previously formulated for the same species (Vagner et al, 2014). The composition and FA content of the two experimental HH and LH diets are summarised in Vagner et al (2015).…”

“…The composition and FA content of the two experimental HH and LH diets are summarised in Vagner et al (2015). For each of these two diets, the fish in two tanks per experimental temperature were fed for at least 4 months (2% of biomass per day) to ensure a good incorporation of dietary lipids into their cell membranes (Vagner et al, 2007(Vagner et al, , 2014(Vagner et al, , 2015. The four experimental conditions were created in duplicate and called HH20, LH20, HH12 and LH12.…”

“…The experimental setup of the swim-tunnel respirometer was the same as described in Vagner et al (2014Vagner et al ( , 2015. Briefly, the respirometer (volume: 10 l) was composed of: (i) a swim chamber with a square working section (40 cm length, 10 cm height, 10 cm width) and (ii) a hydraulic system placed upstream to promote a laminar flow in the swim chamber.…”

“…A has never been determined for C. auratus. We therefore used a value of 0.8, which was estimated in different teleost species (Schurmann and Steffensen, 1994), and has previously been employed for C. auratus (Vagner et al, 2014(Vagner et al, , 2015.…”

“…mass: 36.7±0.6 g, standard length: 12.72±0.3 cm, n=14; LH20 group: 33.1±2.4 g, 12.3±0.3 cm, n=13; HH12 group: 11.6±0.6 g, 8.9±0.2 cm, n=14; LH12 group: 12.3±0.8 g, 8.9±0.2 cm, n=12) were randomly sampled in tanks using a net, and individually tested in the swimtunnel respirometer at their acclimation temperature. Fish were subjected to a step-protocol based on progressive swimming speed increments following the protocol fully described in Vagner et al (2014). At each swimming step, the velocity was maintained for 20 min and ṀO 2 was measured.…”