Heat-treated bean (Phaseolus vulgaris) residue meal as an alternative protein source in pelleted diets for Nile tilapia fingerlings: growth, body composition, and physical characteristics of diets.

The study aimed to evaluate heat-treated bean residue meal (Phaseolus vulgaris)-BRM-as an alternative protein source in diets for Nile tilapia fish. A completely randomized design was used, totaling four (n = 4) dietary treatments: diet without BRM (CON), raw BRM (RBRM) and heat-treated BRM at 100 °C for 15 min (BRM15), and 30 min (BRM30) before inclusion in diets. Nile tilapia fingerlings (1.3 g initial weight) were hand-fed the experimental diets for 66 days, divided equally into three meals per day. Performance parameters, body composition, nutrient retention, and physical characteristics of diets were evaluated. Growth and feed conversion were lower (P < 0.05) in fish fed BRM. Protein productive value was higher (P < 0.05) in fish fed CON diet than in fish receiving BRM. However, 30 min heat treatment of BRM increased (P < 0.05) protein retention in fish. Fish fed BRM30 also had higher protein content (P < 0.05) and reduced body lipid content (P < 0.05) than those fed CON diet. The physical characteristics (durability, dry matter leaching, waterproof time, and water stability time) were significantly improved (P < 0.05) in the BRM30 diet compared with other dietary treatments. The dietary inclusion of BRM at the level of 15% is not recommended for tilapia due to low growth performance and feed efficiency, regardless of preheating treatment. However, research on longer heat treatment time is needed due to the improvements observed in nutrient retention and physical characteristics of diets.

Use of a mixture of vegetal (Jatropha curcas) and animal (fish silage) byproducts as protein source in shrimp (Litopenaeus vannamei) diets

This study evaluated growth responses of white shrimp Litopenaeus vannamei by testing different combinations of Jatropha curcas kernel meal (JCK) and tilapia waste silage (FS) as dietary protein sources under laboratory and pond conditions. A reference diet (RD) based on fish meal was elaborated to contain 35% crude protein and 434 kcal/g; then, five isoproteic and isoenergetic experimental diets were formulated from RD with different FS/JCK proportions as follows: 75%FS/0%JCK; 56.25%FS/13.25%JCK; 26.5%FS/30.89%JCK; 18.75%FS/39.75%JCK; and 0%FS/53%JCK. For the laboratory trial, shrimp (2.90 g) were stocked at 10 m2 in an indoor recirculating system during 90 days. There were differences among the growth parameters of diets. Mean weight gain fluctuated from 6.71±0.61 g observed for the shrimp fed the 75%FS/ 0%JCK diet, to 9.70±0.61 g for the group fed the RD. The RD and 18.75%FS/39.75%JCK diet obtained the highest mean final weight (above 12 g), weight gain (above 9 g), and specific growth rate values (above 1.6%/day). Average final survival was 90.97%. The RD and 18.75%FS/39.75%JCK diets were used for the pond trial. Shrimp (0.49 g) were stocked at 10 m2 within 1-m3 cages into the pond for 35 days. Weight gain (3.47 g) and survival (93.33%) of shrimps were similar between the diets. Quadratic equations with the laboratory data indicated that the maximum responses for growth parameters correspond to FS and JKC inclusion levels in the range of 27.83 to 29.00%, and 32.25 to 33.64%, respectively. A combination of 18.75% FS/39.75%JCK meals as protein source is a potential alternative to effectively substitute FM in practical diets for L. vannamei at the studied ages under both laboratory and pond conditions.(AU)

Crambe (Crambe abyssinica) and sunflower (Helianthus annuus) protein concentrates: production methods and nutritional properties for use in fish feed

ABSTRACT The purpose of this study was to develop and improve protein concentration techniques for two industrial by-products with the potential for use in fish feed. In particular, we chemically characterized crambe meal and sunflower meal and their protein concentrates. Three different protein concentration methods were tested: isoelectric pH (pHi), acid pH and alkaline pH. For crambe and sunflower meals extraction using the pHi method was most efficient in terms of protein yield and crude protein content in the concentrates; this method also increased lysine and methionine content in the concentrates. The water holding capacity of the sunflower protein concentrate was greater than that of the crambe protein concentrate. The crambe protein concentrate had a foam-formation capacity of 15%, which stabilized at 6% after 90 minutes. The protein concentration method also reduced total phenolic content by approximately 50% in the concentrates compared with the meals. Therefore, we conclude that protein concentration using the pHi method is the most efficient technique for crambe and sunflower meals, and the use of this technique can decrease total phenolic compounds while improving meal quality for fish feeding.