|Rawles, Steven - Steve|
Submitted to: Book of Abstracts World Aquaculture Society
Publication Type: Abstract Only
Publication Acceptance Date: 1/14/2003
Publication Date: 2/18/2003
Citation: Gaylord, T.G., Rawles, S.D. Amino acid availability from animal products, blended products and plant products for hybrid striped bass (morone chrysops x m. saxatilis).. Book of Abstracts World Aquaculture Society. 2003. [abstract] p.436. Interpretive Summary:
Technical Abstract: The refining of hybrid striped bass feed formulations has been progressing rapidly. There is still, however, limited information available regarding nutrient digestibility and amino acid availability from common feedstuffs. A pair of experiments was carried out to determine the protein digestibility and amino acid availability to sunshine bass from an assortment of commercially available animal protein sources, blended animal products and plant protein sources in extruded diets. The feedstuffs tested were blood meal, poultry by-product meal, fish solubles, Propak 60, Propak 65, Procon, and FMC for the animal protein sources and brewer's yeast, canola meal, corn gluten feed, peanut meal, mechanically expelled soybean meal (SBME), and sunflower meal for the plant protein sources. Test diets consisted of a 70:30 ratio of nutritionally complete reference diet and test ingredient. Triplicate tanks of fish were fed their respective diets for 7 days prior to collection of feces by stripping. Apparent digestibility coefficients of protein (ADC-P) in the animal products ranged from 39% for FMC to a high of 70% for fish solubles (Table 1). Blood meal, poultry by-product meal, Propak 60, Propak 65, and Procon had intermediate ADC-Ps of 63, 55, 63, 57, and 52%, respectively. ADC-P for the protein in plant sources ranged from 30% for corn gluten feed to 80% for peanut meal. Brewer's yeast, canola meal, SBME, and sunflower meal had intermediate ADC-Ps at 54, 43, 32, and 69%, respectively. Apparent amino acid availability coefficients were variable across animal products and did not necessarily correlate to the ADC-Ps for a given feedstuff. Isoleucine availability was low in blood meal at 38% compared to 59% or better for the remaining amino acids. Lysine, tyrosine and phenylalanine availability from fish solubles was low at 31, 35, and 44%, respectively. Amino acid availability from Propak 60 was consistently higher across all amino acids for the animal products and blends tested. Of the plant products tested, peanut meal was the best performing feedstuff relative to amino acid availability. The amino acid availability from SBME was consistently low for most amino acids tested except lysine and arginine. Corn gluten feed amino acid availability was overall low and lysine availability from corn gluten feed was extremely low at 1%.