Digestibility of animal and vegetable protein ingredients by pirarucu juveniles, Arapaima gigas

Abstract

-The objective of this study was to determine the apparent digestibility coefficients of energy, protein, and amino acids in protein ingredients by pirarucu juveniles. A test was conducted with six protein ingredients: meat and bone meal, fish meal, hydrolyzed feather meal, poultry by-product meal, soybean meal, and corn gluten meal. Three repetitions were used for each tested ingredient. A reference feed was used with 430 g kg −1 crude protein and 19.63 kJ g −1 gross energy. The test feeds consisted of the replacement of 30% of the reference feeds with the test ingredients. Chromium oxide was added to the feeds at 1 g kg −1 as an external marker. Eighteen juveniles with an average weight of 235±36 g were used. The best apparent digestibility coefficients of protein were found for fish meal, followed by the poultry by-product meal and meat and bone meal. However, except for gluten, all the tested ingredients presented protein digestibilities above 0.70. The crude energy apparent digestibility coefficient was higher for animal ingredients, above 0.75, than for vegetable ingredients, which presented values below 0.60. Pirarucu efficiently uses the protein from the tested ingredients, regardless of origin. However, it has a preferential ability to use the energy from animal ingredients.

Apparent digestibility coefficients of selected protein ingredients for pirarucu Arapaima gigas (Teleostei: Osteoglo ssidae)

“…The apparent digestibility of corn gluten feed, hydrolyzed feather meal, fish by-product meal, meat and bone meal, poultry by-product meal and soybean meal were previously evaluated for pirarucu in pelletized diets by Cipriano et al (2016). In comparison to the results found in this study, corn gluten feed and soybean meal (vegetable protein ingredients) presented lower ADCs, probably due to differences in the diet processing method.…”

“…Hydrolyzed feather meal exhibited similar digestibility for crude protein (0.804) and dry matter (0.795), despite the lower ADC for gross energy (0.833). Poultry byproduct meal, fish by-product meal, and meat and bone meal had higher ADCs which can be explained by differences in quality of the raw material and ingredient processing, as well as the lower ash content of the ingredients tested by Cipriano et al (2016).…”

“…For pirarucu, few studies in fish nutrition have been conducted. Limited information ___________________ Corresponding editor: Patricio Dantagnan on nutritional requirements and ingredients digestibilities is available for the species (e.g., Ituassú et al, 2005;Del Risco et al, 2008;Santos-Cipriano et al, 2015;Cipriano et al, 2016), and those are essential for the development of balanced and efficient feeds for the adequate production of pirarucu (Cho et al, 1985;Glencross et al, 2007). Additionally, with increasing demand for protein ingredients to replace fish meal, studies on digestibility and potentiality of such alternative ingredients are even more necessary for the sustainability of the aquaculture industry, specially of carnivorous fish species (Glencross et al, 2007;Tacon & Metian, 2008;Naylor et al, 2009).…”

Digestible Protein Requirement of Pirarucu Juveniles (Arapaima gigas) Reared in Outdoor Aquaculture

“…Each diet was designed to be isoenergetic and isolipidic, based on the digestibility studies developed in our laboratory (Cipriano et al, 2015(Cipriano et al, , 2016. Ingredients of the diets were mixed and extruded mechanically with a 6 mm diameter die (Ferraz Máquinas e Engenharia LTDA, São Paulo, Brazil).…”

“…Note. *Protein and digestible energy based on the percentage of digestibility of ingredient for pirarucu juvenile (Arapaima gigas) of Cipriano et al (2015Cipriano et al ( , 2016. 1 Pratigi Alimentos, Castro Alves, BA, BR.…”