Amending reduced fish‐meal feeds with marine lecithin, but not soy lecithin, improves the growth of juvenile cobia and may attenuate heightened responses to stress challenge

Abstract

Sparing of marine resources in aquafeeds can be environmentally and economically advantageous; however, fish meal (FM) replacement can affect the production performance and physiological competence. Phospholipids are increasingly understood to be involved in maintaining growth and vigour in fish and may be deficient in reduced FM formulations. Accordingly, we evaluated the growth and stress tolerance of juvenile cobia fed typical (50% FM) or reduced FM feeds (12% FM) with or without phospholipid amendment [1% marine lecithin (12% FM + Marine PL) or soy lecithin (12% FM + Soy PL)] for 6 weeks in triplicate tanks (N = 3) in a recirculation aquaculture system. The 50% FM feed yielded significantly superior growth and growth efficiency in comparison with the 12% FM and 12% FM+ Soy PL feeds, but the 12% FM+ Marine PL feed yielded comparable results to 50% FM feed. A low-water stress challenge induced elevated plasma glucose, cortisol and lactate levels in all treatments. However, a significant interaction (diet × stress) effect suggested a lesser cortisol response among fish fed the 12% FM+ Marine PL and 50% FM diets. These findings demonstrate that growth performance and, perhaps, resilience of cobia raised on reduced FM feeds may be improved by the addition of marine-origin phospholipid to the diet.

Nutrition of red drum,Sciaenops ocellatusL.: An additional evaluation of the effects of soya-based diets and supplemental prebiotic

“…In addition, contrary to the lack of dietary effect on plasma lactate in the study ofTrushenski et al (2013), a higher lactate concentration in plasma of red drum fed the soya-based diets were observed in this study. It is unclear whether species (red drum versus cobia, Rachycentron canadum L.), dietary plant-protein level (644 versus 471.2 g/kg) and/or experimental procedures may help to explain the observed differences in plasma lactate.The characterization of the gut microbiota in this study aided at evaluating the potential effects of dietary SP and GBA in juvenile red drum.…”

Saturated Fatty Acids Limit the Effects of Replacing Fish Oil with Soybean Oil with or without Phospholipid Supplementation in Feeds for Juvenile Cobia

“…Alone, these minor differences in protein content and feed intake are unlikely to have substantially affected growth, but perhaps the combination of these effects-not partially hydrogenated soybean oil or PL supplementation-is to blame for the slightly impaired performance observed. Although previous research has suggested that the provision of marine-origin phospholipid is a means of improving the performance and physiological competence of Cobias fed reduced-fish meal feeds, previous and current results suggest that the benefits of soybean lecithin supplementation in juvenile Cobia feeds are limited (Trushenski et al 2013). Niu et al (2008aNiu et al ( , 2008b reported that PL supplementation (8% TABLE 5.…”

Impact of a plant-based diet on behavioural and physiological traits in sea bass (Dicentrarchus labrax)

“…Previous studies on sea bream showed that the replacement of dietary fish oil with vegetable oils (such as linseed oil, but not soybean oil) led to significantly higher plasma cortisol concentrations after acute stress , and significantly higher levels of cortisol release by the head kidney after adrenocorticotropic hormone (ACTH) stimulation (Ganga et al 2011). Similar results have also been shown in sunshine bass (Morone saxatilis) and cobia (Rachycentron canadum) fed reduced fish meal feeds (Laporte and Trushenski 2012;Trushenski et al 2013). The replacement of fish oil with vegetable oils devoid of LC-PUFA results in lower tissue concentrations of arachidonic acid, essential fatty acids and DHA (Ganga et al 2011).…”