Will Pereira de Oliveira

Aminoácidos para frangos de corte

Utilization of digestible amino acid and ideal protein concepts helped to reduce environmental nitrogen excretion and the feed formulation cost without to cause bad performance in broilers. Nevertheless, besides to be recognized that is the best tool at the moment, some factors still should be elucidate to obtain the best utilization of the ideal protein and to reach the best broiler performance. These factors are: knowing about non essential amino acids requirement; utilization good sense to use methodologies to reach amino acid requirement; knowing about amino acid requirement and ideal protein definition for broiler raised in environment and health different.

Utilização das vitaminas C e E em rações para frangos de corte mantidos em ambiente de alta temperatura

This experiment was carried out to evaluate the effect of supplementation of vitamins C or E in the diet on performance, carcass characteristics and hematological parameters of broilers kept under high environmental temperature. Four hundred and fifty broilers were distributed in a completely randomized design with five treatments and nine replications, with 10 and 7 birds per experimental unit, respectively, according to the periods from 1 to 21 and 22 to 42 days old. Treatments consisted of a basal diet (RB) without supplementation of vitamins C and E; RB + 300 ppm of vitamin E; RB + 230 ppm of vitamin C; RB + 300 ppm of vitamin E + 230 of vitamin C, and RB + 150 ppm of vitamin E + 115 of vitamin C. Treatments did not influence performance of birds in the phase of 1 to 21 days of age. At 1 to 42 days of age, supplementation of vitamins C and E only influenced feed conversion. The best results for the absolute and relative weights of breast were observed in birds fed the basal diet supplemented with different combinations of vitamins C and E. Plasma concentration of triiodothyronine, percentage of blood cells, the heterophil/lymphocyte ratio and absolute and relative weights of the spleen at 21 and 42 days of age were not influenced by vitamin supplementation. Supplementation of vitamins C and/or E did not influence performance, weight of the spleen or blood parameters of chickens maintained until 42 days of age in a high temperature environment. The combination of vitamins C and E promotes improvement in absolute and relative weights of breast of broilers reared under high temperature

Lisina digestível para suínos machos castrados de alta deposição de carne submetidos a estresse por calor dos 30 aos 60 kg

This study was conducted to evaluate levels of digestible lysine for pigs at 30 to 60 kg kept under heat stress. It was used 70 castrated animals kept in environment at 30oC and others 70 kept at 34oC, distributed in a randomized block design, with five treatments (0.83, 0.93, 1.03, 1.13 and 1.23% digestible lysine), and seven repetitions with two animals per experimental unit. The daily weight gain of the animals kept at 30oC increased up to 1.04% of digestible lysine, whereas it did not change at 34oC. Feed daily intake of animals at 30oC and 34oC did not change with levels of lysine. Daily lysine intake of animals, in both environments, increased according to the level of lysine in the diet. At 30oC, feed conversion improved up to the level of 1.07% lysine, whereas at 34oC, it did not vary among lysine levels. Regardless of the temperature, use efficiency of lysine decreased as levels of lysine increased and it was 4.4% worse in the environment with higher temperature. Protein deposition in carcass in the 30oC environment increased up to the level of 1.05% lysine, but it did not change at 34oC. At 30oC, fat deposition decreased down to 1.08% lysine, whereas in the 34oC environment, it increased up to 1.08%, and it was on average 25.6% lower than at 30oC. Levels of triiodothyronine and thyroxine were 35 and 30%, respectively, which was lower in animals kept in the 34oC environment, where respiratory rate and rectal temperature were higher than those observed in animals kept in the environment at 30oC. The levels of 1.04 and 0.83% of digestible lysine provide greater weight gain and protein deposition in pigs kept in environments at 30oC and 34oC, respectively.

Níveis de cromo orgânico na dieta de codornas japonesas mantidas em estresse por calor na fase de postura

The objective was to evaluate the effects of the addition of organic chromium in the diet of Japanese quails in the initial fase of laying, under heat stress. Six hundred quails averaging 63 days old and initial body weight of 158.60 g on high temperature environment (32oC) were used. Diets were based on corn and soybean meal, and supplemented with five levels of chromium (0, 500, 1,000, 1,500, and 2,000 ppb), from chromium-methionine, in replacement with innert material. The experimental design was completely randomized, with 12 experimental units per treatment and ten birds in each experimental unit. The least significant level for Cr inclusion in the diet was obtained using the Willians test, at 5% significance level, on the following variables: egg production (total egg production, egg production by lodged bird and commercial egg production by lodged bird, egg weight), feed intake, feed conversion (by kg of egg and by dozen of egg) and egg mass. The level of 500 ppb increased the egg commercial production by lodged bird. Feed intake increased at 2000 ppb Cr. Other variables were not influenced by the different supplemental Cr levels. The results allow to conclude that 500 ppb of supplemental chromium, from chromium-methionine, was able to improve the egg commercial production of laying Japanese quail under heat stress.

Dietary crude protein reduction on growth and carcass performance of 22 to 42-day-old broilers reared under different temperatures

This study was conducted to verify the effects of dietary crude protein reduction on growth and carcass performance of 22-42-day-old broilers reared under different temperatures. Treatments were set up in a five by two factorial arrangement, with five crude protein levels (220, 210, 200, 190 and 184 g/kg) and two temperatures (21.6 and 32.2 oC). Diets were isocaloric and essential amino acid-to-lysine ratio was maintained constant in all treatments. There was no interaction between crude protein reduction and environmental temperature for any of the parameters evaluated. Crude protein had no influence on feed intake. Nevertheless, weight gain and feed conversion ratio were linearly influenced by crude protein reduction. Worse performance was also observed in birds exposed to heat stress as compared with birds kept under thermoneutral temperature. There was no effect of crude protein reduction on breast and legs. Birds kept under heat stress had lower breast yield and higher leg yield as compared with broilers reared at 21.6 oC. Any crude protein reduction in the range of 220 to 184 g/kg for 22 to 42-day-old broilers has a negative effect on their performance. Heat stress worsens broiler performance and breast yield.

Lysine levels in diets for broilers from 8 to 21 days of age

This study was conducted to evaluate the effects of digestible lysine levels in diets with and without supplementation of industrial amino acids on performance and fat deposition in the carcass of broilers in the starter phase. One thousand four hundred and forty chickens with initial weight of 168.1±5.0 g were distributed in a completely randomized experimental design, in a 5 × 2 factorial arrangement, composed of five digestible lysine levels (10.0, 11.0, 12.0, 13.0 and 14.0 g/kg) and two types of diet (diet with different proportions of corn and soybean meal and diet supplemented with industrial amino acids to obtain the digestible lysine levels), with eight replications and 18 birds per replication. There was interaction effect only on weight gain and fat deposition in the birds. The lysine levels reduced feed intake linearly in both diets, but caused a linear increase in lysine intake. The lysine levels quadratically affected weight gain and feed conversion, which improved up to the estimated levels of 13.0 and 12.8 g/kg lysine, respectively, when the corn:soybean meal ratio of the diet changed. In the diets supplemented with amino acids, the lysine levels increased weight gain and improved feed conversion linearly. Regardless of the type of diet, protein deposition increased linearly, whereas fat deposition reduced also linearly, as the lysine levels in the diets were increased. The levels of 13.0 and 14.0 g/kg digestible lysine provide, respectively, the best performance in birds fed a diet in which the proportion of corn and soybean meal varies and a diet supplemented with industrial amino acids, in the period from 8 to 21 days of age.

Relação treonina: lisina digestíveis na dieta de poedeiras leves de 42 a 58 semanas de idade

This study was conducted to determine the ideal ratio of digestible threonine: lysine in diets for laying hens at 42 to 58 weeks of age. Two hundred forty Hy Line W-36 laying hens were used at 42 weeks of age for 16 weeks. The treatments were distributed in a completely randomized design with eight replicates and six birds each. The experimental diets were formulated with five levels of digestible threonine (0.461; 0.515; 0.569; 0.622 and 0.676%) providing the five ratio of digestible threonine: lysine (60; 67; 74; 81 and 88%) studied. The variables analyzed were: egg production; feed intake; lysine intake; threonine intake; mass egg; average egg weight; lysine use efficiencies by mass and produced eggs; feed conversion per mass and dozen eggs; Average weights yolk, albumen and shell; weight gain and final body weights of birds; and nitrogen balance. The digestible threonine: lysine ratio in the diet did not influence the analyzed variables except consumption of threonine which showed a linear effect. The ideal ratio of digestible threonine: lysine in diets for white laying hens at 42 to 58 weeks of age is 60%, which corresponds to the level of 0.461% of digestible threonine in the diet and daily intake of digestible threonine 446mg/bird.

Digestible lysine levels obtained by two methods of formulation of diets for 22-to-42-day-old broilers

The objective of this study was to evaluate the effect of digestible lysine levels in diets with or without supplementation of industrial amino acids on performance, carcass characteristics and nitrogen excretion in broilers of 22 to 42 days of age. Birds were distributed in a completely randomized experimental design in a 4 × 2 factorial arrangement, with four digestible lysine levels (9.0, 10.0, 11.0 and 12.0 g/kg) and two methods to obtain the lysine levels (variation in the proportion of corn and soybean meal, without supplementation; or supplementation of industrial amino acids), eight replicates and 20 birds per replicate. There was an interaction effect on the performance characteristics and on the weights and yields of prime cuts. In both diets, feed conversion improved linearly as the lysine levels were increased. Feed intake; weight gain; carcass, thigh and drumstick weights; and boneless breast yield increased and abdominal fat reduced linearly as the lysine levels were increased in the unsupplemented diet. The lysine levels of the supplemented diets linearly reduced the yield of drumstick and quadratically reduced the yields of bone-in and boneless breast up to the estimated levels of 10.4 and 10.7 g/kg, respectively. Diets without supplementation increased the excretion and retention of nitrogen. The levels of 9.0 and 12.0 g/kg digestible lysine obtained with supplementation of industrial amino acids and without it, respectively, provide the best performance and yield of prime cuts in the birds. Diets in which the digestible lysine levels are obtained without supplementation provide better performance responses and carcass characteristics compared with supplemented diets.