ABSTRACT The objective of this study was to evaluate levels of inclusion of an enzyme complex (EC) in corn- and soybean meal-based diets for laying hens on the digestibility of nutrients and energy. A metabolism trial was conducted using 75 Dekalb Brown laying hens at 26 weeks of age, which were distributed into five treatments with five replicates in a completely randomized design. The ingredients used in the diets received an additional (enriched) 3% methionine, lysine, cysteine, threonine, tryptophan, and […]

This experiment was carried out to evaluate the effects of levels of methionine and lysine on performance and on the internal and external egg quality of commercial laying hens. It was used 256 Hisex White laying hens at 68 weeks of age, which were individually housed in a complete random design in a 4 õ 4 factorial scheme with four levels of lysine (0.482, 0.682, 0.882, and 1.082%) and of methionine (0.225, 0.318, 0.411, and 0.505%) totaling sixteen diets with […]

Aiming at determining levels of digestible sulfurous amino acids to establish the ideal methionine + cystine/lysine relationship in rations for light-weight laying hens in the period from 42 to 58 weeks of age, 216 birds of the commercial brand Hy- Line W36 were distributed in a randomized block design with 6 diets, 6 repetitions and 6 birds per experimental unit. The level of digestible lysine used in the experimental diet was 0.770% for an expected average consumption of 731 mg/hen/day […]

The experiment was carried out to evaluate the effects of diets with different levels of crude protein (CP) and lysine (LYS) on characteristics of performance, egg internal quality, and nitrogen balance/retention. It was used 160 Hisex White laying hens at 48 weeks of age, individually accomodated in a complete random design in a 4 × 2 factorial scheme with four levels of crude protein (12, 14, 16 and 18%) and two levels of lysine (0.85 and 1.00%), totalizing eight treatments […]

This experiment was carried out to evaluate the tryptophan (Trp) requirements and the recovery performance pattern of laying hens fed Trp-deficient diets. One hundred sixty Hisex White commercial laying hens were randomly distributed in five Trp levels in the diets (0.13, 0.15, 0.17, 0.19 and 0.21% ) with eight replicates of four birds. The laying hens remained for two weeks in adaptation (51 to 52 weeks), for six weeks for evaluation of Trp requirements (53 to 58 weeks) and for […]

The effects of feeding different calcium levels and limestone particle sizes on body and morphometric development of the digestive tract in replacement pullets were evaluated in this trial. One thousand and four hundred Lohmann LSL replacement pullets were assigned to a complete randomized design with a 5 x 2 factorial (calcium levels and limestone particle size) and five replicates of 28 and 18 birds/plot, respectively, for the periods from 3 to 7 and from 8 to 12 weeks old. The […]