The adequate level (0.12, 0.16, 0.20, 0.24, and 0.28%) of the dietary digestible tryptophan was evaluated in 400 laying Japanese quail from 21 to 30 weeks old. The animals were housed in laying cages, with initial weight of 158.50 g and egg production average of 84.50%. A completely randomized blocks design, with eight blocks, five diets, eight replicates of ten birds per replicate and three experimental periods of 21 days each was used. Feed intake (g/bird/day), digestible tryptophan intake (mg/bird/day), […]

The nutritional requirement of digestible lysine was determined in 180 Lohmann LSL white-egg laying hens raised from 79 to 95 weeks of age. The birds were allotted to five levels (0.555; 0.605; 0.655; 0.705 and 0.755%) of digestible lysine, six replicates and six birds per experimental unit. Quadratic effect of digestible lysine levels on feed intake, average weight gain, feed conversion/egg mass, the egg weight and the egg mass was observed. For the characteristics digestible lysine intake, feed conversion/dozen eggs […]

A total of 84 barrows and females from a commercial hybrid (Agroceres × MS60), averaging 15.3 kg, was raised from 15 to 35 kg to evaluate the effect of different dietary levels of metabolizable energy (ME) and crude protein (CP) formulated according to the ideal protein concept and phytase supplementation on performance and carcass characteristics. The experiment was analyzed as a complete randomized block design, in a factorial arrangement of treatments 3 × 2 + 1, with three ME levels […]

An experiment was carried out with the objective of evaluating the effect of different lysine levels in diets supplemented or not with ractopamine (RAC) on the performance and carcass characteristics of finishing barrows. Forty commercial hybrid swines were distributed to a randomized experimental block design, in a 2 x 2 factorial arrangement, with two digestible lysine levels (0.67 and 0.87%), with adjustment for the others amino acids to achieve an ideal protein relationship, and two levels of RAC (0 and […]

This study was aimed to evaluate the effects of the dietary digestible lysine levels and environmental temperature on performance and carcass characteristics of broiler chickens from 22 to 42 days-old. Six hundred seventy two males Ross® broiler chickens with an average weight of 726 g were allotted to a completely randomized design, in a 4 × 4 factorial arrangement with six replicates and seven birds per experimental unit. The chickens were fed with different digestible lysine levels in the diet […]

Two experiments were conducted to evaluate dietary levels of crude protein (CP) and digestible lysine (LYSD) on the performance and nitrogen (N) excretion of piglets in the initial phase. In experiment 1, 80 barrows and females (initial weight of the 9.1 kg ± 1.2 kg and final weight of the 21.5 ± 4.8 kg), crossbred (Landrace x Large White), were distributed to a randomized blocks in factorial scheme 2 x 4 (two levels of CP 16 and 18% – and […]

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 […]

Fifty and two lactating sows were allotted to a randomized complete blocks experimental design with four digestible threonine levels (0.64; 0.67; 0.70 and 0.73%) and 13 replications, and each experimental unit was consisted by a female. The temperature inside in the room was of 29.7 ± 2.5°C. There was no effect of digestible threonine levels in the diet on the weight of the sows at weaning. The total and percentage sow weight losses linearly reduced with the increase of digestible […]

With the objective of determine the nutritional requirement of lysine for growing white-egg and brown-egg laying hens in the period from 1 to 3 and 4 to 6 weeks of age, 480 birds were used in the period from 1 to 3 weeks of age and 432 birds in the period from 4 to 6 weeks of age. In both periods, Hy-line birds were used; 50% Hy-line W 36 (White) and 50% Hy-line Brown in completely randomized design in a […]

This experiment was carried out to evaluate the influence of the reduction of dietary CP levels and amino acid supplementation on performance of barrows maintained in a high environmental temperature. A total of sixty crossbreed (Landrace x Large White) piglets (average body weight = 29.8 kg) was allotted in a completely randomized experimental design with five treatments (17, 16, 15, 14 and 13% CP), six replications and two animals per experimental unit. Diets and water were suplied ad libitum until […]