Use of the concept of saturation kinetics to interpret responses of brown laying hens to levels of tryptophan biomass in the diet

Abstract

The In order to elaborate this proposal, a bibliography was carried out on sources and requirements of tryptophan for brown laying hens in the last six decades. Based on the reviewed studies, at least three findings were made, the first being in relation to the sources used in the studies, which used a single source of tryptophan, l-tryptophan 98%. The second is in relation to the use of the concept of digestible amino acids, which was only reported in publications from 2008 onwards. The third is that only one study on digestible tryptophan requirement was found for brown laying hens in the last two decades. Considering the increasing production of biomass amino acid, which differs from the conventional source due to the amount of biomass, which can reach 40% of the total product. Due to the growing production of amino acid biomass and the small number of studies on tryptophan requirement for brown laying hens, this research was defined with the aim of updating the egg production requirement of brown birds using tryptophan biomass as a source. A completely randomized trial will be carried out, with eight treatments and 11 repetitions of three birds. The treatments will consist of levels of tryptophan in the diet, 0.112%, 0.127%, 0.142%, 0.157%, 0.172%, 0.187%, 0.202% and 0.225% obtained by the supplementation technique. The trial will run for 16 weeks. The variables egg production, egg weight, egg mass and feed conversion will be analyzed using a saturation kinetics model considering tryptophan intake as an independent variable. It is expected at the end of the research to provide producers with an update of the tryptophan requirement and describe the use of l-tryptophan biomass for brown laying hens.