Effects of the dietary protein : lipid ratio on growth and nutrient utilization in gilthead seabream (Sparus aurataL.)

Abstract

Gilthead seabream Sparus aurata L. (initial mean body weight: 42.5 g) were fed four experimental diets containing either 47 or 51% of dry matter (DM) as protein and either 15 or 21% as lipid for 12 weeks. Each diet was hand‐distributed to triplicate groups of 60 fish, three times a day until satiation. The digestibility coefficients of the dietary components were determined using chromic oxide as a marker. The levels of protein or lipid in the diets did not affect the digestibility. Fish regulated their feed intake and attained the same weight at the end of the experiment. However, feed efficiency varied between diets, with best values obtained with both diets containing 21% lipid. When diets contained only 15% lipid, feed efficiency increased with dietary protein level. Nitrogen retention was significantly higher with high fat diets regardless of dietary protein level. Neutral lipid deposition was significantly higher in liver for diets rich in lipids. It was elevated in muscle only in fish fed the diet containing 47% protein and 21% lipid and this deposition in muscle contributed to a significant increase in body fat content. Phosphorus load to the environment, measured as percentage retention of ingested or digestible phosphorus, was significantly lower with both diets higher in lipids.

Optimum dietary crude protein requirement for juvenile cachama Piaractus brachypomus

“…In different species, it has been observed that when the diet is low in energy or in an essential nutrient for growth such as proteins, the animal compensates such deficiency by increasing its consumption (GUILLAUME et al, 2004). According to SANTINHA et al (1999), when a fish is fed to satiety, weight gain will depend not only on the energy and nutrient content of the diet, also in its ability to regulate food intake. Consequently, these theories could explain the higher feed ingestion by P. brachypomus fed diets isoenergetics with low protein.…”

The effect of using different commercial feeds in sea bream (Sparus aurata L. 1758) and sea bass (Dicentrarchus labrax L. 1758) aquacultured in the Güllük Gulf (Muğla, Türkiye) on fatty acid profile

“…The results obtained in this study are consistent with those of Izquierdo et al (10), who investigated sea bream fingerlings fed with a vegetable oil mixture. Other studies (11,12) examined the effect of protein and fat rate used in sea bream feed on growth and revealed that feed conversion ratio increases in parallel with the increase of protein level. Similarly, it was determined that soybean, sunflower, and fish oil added to fish feed of sea bass at different rates did not have a significant impact on growth performance (13,14).…”

Effects of dietary carbohydrate/lipid ratios on growth, body composition, and nutrient utilization of hybrid catfish (Pseudoplatystoma reticulatum x Leiarius marmoratus)

“…According to Santinha et al (1999) an increase in dietary lipid content leads to a significant decrease in feed intake. However, in the present study no significant difference (p>0.05) in food intake was observed.…”