Combined effects of nutritional, biochemical and environmental stimuli on growth performance and fatty acid composition of gilthead sea bream (Sparus aurata)

Abstract

The reliance of the aquafeed industry on marine resources has to be reduced by innovative approaches in fish nutrition. Thus, a three-factorial approach (fish oil reduced diet, phytochemical genistein, and temperature reduction) was chosen to investigate the interaction of effects on growth performance and tissue omega-3 long chain polyunsaturated fatty acid (LC-PUFA) levels in juvenile sea bream ( Sparus aurata , 12.5 ± 2.2 g). Genistein is a phytoestrogen with estrogen-like activity and thus LC-PUFA increasing potential. A decrease in the rearing temperature was chosen based on the positive effects of low temperature on fish lipid quality. The experimental diets were reduced in marine ingredients and had a fish oil content of either 6% dry matter (DM; F6: positive control) or 2% DM (F2: negative control) and were administered in the plain variant or with inclusion of 0.15% DM genistein (F6 + G and F2 + G). The feeding trial was performed simultaneously at 23°C and 19°C. The results indicated that solely temperature had a significant effect on growth performance and whole body nutrient composition of sea bream. Nevertheless, the interaction of all three factors significantly affected the fatty acid compositions of liver and fillet tissue. Most importantly, they led to a significant increase by 4.3% of fillet LC-PUFA content in sea bream fed with the diet F6 + G in comparison to control fish fed diet F6, when both groups were held at 19°C. It is hypothesized that genistein can act via estrogen-like as well as other mechanisms and that the dietary LC-PUFA content may impact its mode of action. Temperature most likely exhibited its effects indirectly via altered growth rates and metabolism. Although effects of all three factors and of genistein in particular were only marginal, they highlight a possibility to utilize the genetic capacity of sea bream to improve tissue lipid quality.

Evaluation of dietary methionine sources on growth performance and antioxidant potential of gilthead seabream juveniles reared at high water temperature

“…The whole‐body dry matter, protein, and lipids were higher in fish reared at 29°C than at 22°C, while ash was not affected by water temperature. In a previous study, it was observed that whole‐body dry matter and lipids of gilthead seabream increased in fish reared from 19 to 23°C (Torno et al, 2019). However, in another study, the whole‐body composition of gilthead seabream juveniles was not affected in fish reared at 18 or 25°C (Couto et al, 2008).…”

Harvesting the benefits of nutritional research to address global challenges in the 21st century

“…During the 2010–2020 decade, after the key NRC publication (NRC, 2011), there was an increasing level of definition of requirements for animals of different sizes and in some cases different environmental constraints (e.g., hypoxia, temperature, salinity, etc.). Both age and environmental conditions may markedly affect fish physiology and modulate the expression of key genes, affecting nutrient utilization and nutritional requirements (Fernández‐Palacios et al, 2011; Hamre et al, 2013; Izquierdo & Koven, 2011; Lund et al, 2019; Torno et al, 2019). However, such information is still scattered or absent for some species (e.g., Seriola , Sole) (Sicuro & Luzzana, 2016; Valente et al, 2019).…”

Review on Gilthead Seabream (Sparus aurata) Aquaculture: Life Cycle, Growth, Aquaculture Practices and Challenges

“…Growth is an integrated physiological process in which the ingested energy is converted to biomass. In gilthead seabream, the efficacy of this conversion is regulated by the genetic growth potential of fish and various abiotic factors such as food quality and disponibility, temperature, photoperiod, and salinity [41][42][43]. Like most teleosts, it demonstrates indeterminate growth, with its muscle mass increasing via hyperplasia and hypertrophy throughout its lifespan [18,44,45].…”

“…In addition to the physico-chemical parameters of the aquatic environment, the growth is affected by many other factors, including the genetic component, food availability, and dietary quality [42,49]. Table 1 summarizes the nutritional requirements of gilthead seabream.…”