Resumo
This study aimed at evaluating the effects of feed form and diet metabolizable energy levels (ME) on broiler chickens performance from 1 to 21 days of age. Four hundred and eighty chickens were randomly assigned in a 2 x 3 factorial scheme: ME (2900 and 3050 kcal/kg) and feed form (mash, crumbled, and extrused), with four replicates of 20 birds each. No interaction was observed between the factors on performance characteristics from 1 to 7 and 1 to 14 days. The studied factors did not influence chickens performance from 1 to 7 days. At 14 days, chickens fed extrused diets showed lower feed intake without impairing other characteristics. Also, broilers fed diets containing 3050 kcal/kg ME had better weight gain and feed conversion without influencing feed intake. A significant interaction between factors was found for weight gain and feed conversion from 1 to 21 days, where broilers fed crumbled diets with 2900 kcal/kg ME showed better performance. Feed intake was not influenced by ME in any age. It is possible to conclude that the use of crumbled diet allows a reduction in ME and promote better performance in relation to extrused and mash diet. Broilers chickens at initial phase do not control the feed intake according to ME of the diet at the studied levels. KEY-WORDS: Crumbled diet. Extrused diet. Mash diet. Metabolizable energy. Pelleted diet. Performance.
Resumo
The aim of this study was to evaluate the digestible tryptophan level(dig. Trp) for laying Japanese quail diets. Four hundred Japanese quail aging 21 to 30 weeks were housed in laying cages, with initial average weight of 158.50 g and egg production of 84.50%. The experimental arrangement consisted on a randomized design, containing eight blocks, five of tryptophan levels (0.12, 0.16, 0.20, 0.24 and 0.28% dig. Trp), eight replicates of ten birds and three experimental periods of 21 days. The evaluated parameters were feed intake (g/bird/day), egg production (%/bird/day), average weight of eggs (g), weights of yolk (g), albumen (g), shell (g), percentage of shell (%), specific gravity (g/cm3) and Haugh units. The tryptophan level affected (P<0.05) all parameters, except feed intake, average eggs weight and weight of yolk. The performance of quails using the statistical adjustment through quadratic regression, broken-line regression model, suggested that the minimum requirement of diets of digestible tryptophan is 0.21% of the diet, allowed the daily intake of 45.0 mg of tryptophan per bird, and the corresponding ratio between digestible tryptophan and digestible lysine was 21%. KEY-WORDS: Amino acids. Coturnix coturnix japônica. Exigency Quality of eggs.
O objetivo deste trabalho foi avaliar os níveis de triptofano digestível (Trp dig.) em dietas para codornas japonesas em fase de postura. Foram utilizadas 400 codornas japonesas de 21 a 30 semanas de idade, alojadas em gaiolas de postura, com peso inicial de 158,50 gramas e produção média de ovos de 84,50%. O delineamento experimental foi em blocos casualizados, constituído por oito blocos, cinco tratamentos(0,12; 0,16; 0,20; 0,24 e 0,28% Trp dig.), oito repetições de dez aves/repetição e três períodos experimentais de 21 dias cada. As variáveis avaliadas foram consumo de ração (g/ave/dia), produção de ovos (%/ave/dia), peso médio dos ovos (g), pesos de gema (g), albúmen (g), casca (g), porcentagem de casca (%), gravidade específica (g/cm3) e unidades Haugh. Todas as variáveis apresentaram efeitos (P