Apparent Protein and Energy Digestibility and Amino Acid Availability of Corn and Co‐products in Extruded Diets for Nile Tilapia, Oreochromis niloticus

Abstract

We assessed the nutritional value of corn in extruded diets for Nile tilapia, Oreochromis niloticus, by determining the apparent digestibility coefficients of dry matter, crude protein, and gross energy, and by measuring the apparent availability coefficients (AACs) of essential and non‐essential amino acids (AAs) in several corn‐based diets. We fed 180 juvenile Nile tilapia a reference diet containing 325.8 g/kg crude protein and 4613 kcal/kg gross energy or a test diet containing a 70:30 mixture of the reference diet and a test ingredient (whole corn, corn germ, corn germ meal, corn gluten feed, or corn gluten meal). The apparent digestibility coefficients ranged from 56.3 to 96.6% (dry matter), 89.4 to 96.8% (crude protein), and 59.0 to 95.4% (gross energy). The AACs of all AAs exceeded 80% for all diets and were >90% for corn gluten meal. All ingredients showed high levels of apparent digestibility for crude protein and high AACs of AAs. Diets based on whole corn or corn gluten meal showed higher digestibility values for dry matter and gross energy, suggesting that they are preferable choices for Nile tilapia.

Replacement of soybean meal by peanut meal in diets for juvenile Nile tilapia, Oreochromis niloticus

“…This correlation has been reported in other studies (Guimarães et al, 2012;Vidal et al, 2015). The GE digestibility observed in this study was similar to values reported for silver perch (77%) (Allan et al, 2000) but lower than values reported for hybrid tilapia, O. niloticus × O. aureus (81.5%) (Zhou & Yue, 2012).…”

Total and available tryptophan requirement of Nile tilapia,Oreochromis niloticus, fingerlings

“…It is necessary to meet the optimal requirements of all essential amino acids in aquafeeds, because deficiency in one may cause impaired utilization of the other amino acids, and protein synthesis will be negatively affected. In recent years, available amino acids' values of many feed ingredients have been addressed for Nile tilapia (Guimarães, Pezzato, & Barros, ; Guimarães, Pezzato, Barros, & Tachibana, ; Vidal et al., , ; Xavier, Michelato, Vidal, Furuya, & Furuya, ), in order to elaborate more precise diets to maximize dietary nitrogen utilization and improve sustainability of farmed fish. Moreover, dietary requirements should be determined based on available amino acids, to formulate oriented environmental diet because the availability coefficients of amino acids are quite variable among feeds (Guimarães, Pezzato, & Barros, ) and fish species (NRC, ).…”

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

“…For the omnivorous channel catfish Ictalurus punctatus, the apparent crude protein digestibility for corn gluten feed was satisfactory (0.881) whereas the ADCs for gross energy (0.423) and dry matter (0.393) exhibited low values (Kitagima & Fracalossi, 2011). Vidal et al (2015) also observed such trend of high ADC for crude protein (0.912) and low for energy (0.590) and dry matter (0.563) when testing this ingredient for Nile tilapia. In the present study, protein digestibility of corn gluten feed for pirarucu was lower in comparison to the values obtained for channel catfish and Nile tilapia.…”

“…Different superscripts letters in the same row indicate different means by Tukey's test (P < 0.05). (Abimorad et al, 2008), channel catfish (Kitagima & Fracalossi, 2011) and Nile tilapia (Vidal et al, 2015), as well as for carnivorous species, such as cobia Rachycentron canadum (Zhou et al, 2004), dourado Salminus brasiliensis (Borghesi et al, 2009), Atlantic salmon Salmo salar (Burr et al, 2011) and Northern snakehead Ophiocephalus argus (Yu et al, 2013), showing protein and energy ADCs values ranging from 0.856 to 0.968 and from 0.827 to 1.045, respectively. However, low palatability (Park et al, 1997;Cha et al, 2000;Bicudo et al, 2012), imbalance in essential amino acids (Mente et al, 2003;Abimorad et al, 2008) and high price should also be assessed in future studies on the use of this ingredient for pirarucu.…”