Rodrigo Santana Toledo

Níveis dietéticos de proteína bruta para frangos de corte de 1 a 21 e 22 a 42 dias de idade

Two experiments were carried out to determine the ideal levels of crude protein (CP) for Ross broiler chickens from one to 21 and 22 to 42 days of age, of both sexes. The parameters evaluated were weight gain (WG), feed intake (FI), feed:gain ratio (F/G) and carcass evaluation (CV). In the starting phase (1 to 21 days of age), different protein levels (20.00; 20.50; 21.00; 21.50; 22.00 and 22.50%) were used in diets containing 1.27% total lysine. In growing phase (22 to 42 days of age), the dietary protein levels were 17.50; 18.00; 18.50; 19.00 and 19.50% with 1.16% total lysine. In both experiments, were maintained ratio lysine: methionine+cystine, threonine, tryptophan and arginine, considering the ideal protein profile. In both experiments, a completely randomized block experimental design, in a 2x6 and 2x5 (two sexes and six or five dietary lysine levels) factorial arrangement, was used, with six replicates, using a total of 1440 and 1200 birds, respectively. Considering bird performance, the dietary CP requirement estimate from 1 to 21 days, for the males was 22.42% CP, while the females showed linear effect for WG and F/G. In the growing phase (22 to 42 days of age), the protein levels affected linearly males FI, F/G, breast yield and abdominal fat. Females showed quadratic effect for WG and linear effect for F/G and abdominal fat. The requirements of the crude protein estimates for male and female, respectively were: 22.4 and 22.5% CP for starting phase and 19.5 and 18.5% CP growing phase.

Níveis dietéticos de lisina para frangos de corte de 1 a 21 e 22 a 40 dias de idade

Two experiments were carried out to determine the nutritional requirement of total lysine for Ross broiler chickens from one to 21 and 22 to 40 days of age, of both sexes. The parameters evaluated were weight gain, feed intake, feed conversion and carcass evaluation. In each experiment, a completely randomized experimental design, in a 2 x 6 (two sexes and six dietary lysine levels) factorial arrangement with six replicates, using a total of 1440 birds, was used. The basal diets with 1.03% total lysine, 22.0% CP and 3000 kcal ME/kg in the first experiment and 0.92% total lysine, 20.0% CP and 3150 kcal ME/kg in the second experiment, suplemented with six levels pure lysine (0.0; 0.06; 0.12; 0.18; 0.24 and 0.30%), were used. Considering weigth gain and feed conversion, the dietary requirement estimates for the experiment from 1 to 21 days were 1.303 and 1.249% total lysine and 1.183 and 1.129% digestible lysine for males and females, respectively. For the experiment from 22 to 40 days, the performance and evaluation carcass values were 1.164 and 1.143% total lysine and 1.044 and 1.023% digestible lysine for males and females, respectively.

Efeito da Relação Arginina: Lisina sobre o Desempenho e Qualidade de Carcaça de Frangos de Corte de 3 a 6 Semanas de Idade, em Condições de Alta Temperatura

An experiment was run using 720 male Ross chicks, grown from 22 to 42 days of age under high environmental temperature condition (26.2 to 30.5oC), to evaluate the effect of the digestible arginine:lysine (Arg:Lys) ratio on performance and carcass quality of broiler chickens. A complete randomized design with six treatments (95.0, 102.5, 110.0, 117.5, 125.0 and 132.5% Arg:Lys ratio), six replicates and 20 birds per experimental unit was used. There was no significant effect on broiler performance, however Arg:Lys ratio linearly improved leg quarter yield and linearly decreased abdominal fat.

Níveis nutricionais de cálcio e de fósforo disponível para aves de reposição leves e semipesadas de 13 a 20 semanas de idade

Four experiments were accomplished using 720 white-egg pullets and 720 brown-egg pullets from 0 to 6 age weeks, were allotted to a completely randomized design with five calcium levels (.70, .80, .90, 1.00, and 1.10%) or five levels of available phosphorus (.30, .35, .40, .45, and .50%), with four replicates and 18 pullets for experimental unit. The experimental diets were formulated with soybean meal and corn to contain 2900 kcal of metabolizable energy/kg of diet, 18% crude protein, .70% calcium for calcium experiments and .30% of available phosphorus for phosphorus experiments. Diets and water were ad libitum fed during the experimental period. The evaluated characteristics were weight gain, feed intake, feed: gain ratio, bone resistance, bone ash and bone calcium (calcium experiments) or bone phosphorus (experiments of available phosphorus). Requirements of .937% and .961% of calcium and .420% and .423% of available phosphorus for white-egg pullets and brown-egg pullets, respectively, were estimated.

Composição bromatológica, energia metabolizável e equações de predição da energia do grão e de subprodutos do trigo para pintos de corte

The apparent metabolizable energy (AME) and nitrogen corrected apparent metabolizable energy (AMEn) values were determined and energy prediction equations obtained using the chemical composition of 11 feedstuffs. The feedstuffs evaluated were: brown flour meal, wheat flour, wheat grain, wheat grain residue, wheat germ, cookies residue, macaroni residue and, four wheat brans. Total excreta collection method was used, with 480 broiler chicks, 16 to 24 days old. A randomized complete design was utilized, with 11 feedstuffs and a basal reference diet, using four replications and ten birds per experimental unit (five males and five females). Each feedstuff replaced the reference diet at the amount of 40%. The feedstuffs AME and AMEn values expressed in kcal/kg of dry matter (DM), varied from 1807 to 1758 for wheat bran 3 and from 4480 to 4339 for cookies residue, respectively. The prediction equations that best estimated (R2 = 98%) AME and AMEn values were those in which crude protein (CP) and/or neutral detergent fiber (NDF) contents, were used AME (kcal/kg DM) = 4910,03 - 47,82*CP - 47,77*NDF; and AMEn (kcal/kg DM)= 4754.02 - 48.38*CP - 45.32*NDF.

Composição química e energética de amostras de milho submetidas a diferentes temperaturas de secagem e períodos de armazenamento

O objetivo do experimento foi determinar a composicao quimica, energia bruta, energia metabolizavel aparente (EMA) e energia metabolizavel aparente corrigida (EMAn) de amostras de milho submetidas a diferentes temperaturas de secagem (temperatura ambiente e secagem artificial com temperaturas de 80, 100 e 120oC) e a diferentes periodos de armazenamento (0, 60, 120 e 180 dias). Para determinar os valores de EMA e de EMAn, foi utilizado o metodo tradicional de coleta total de excretas com pintos machos, Avian Farm, de 21 a 30 dias de idade. Utilizou-se um esquema fatorial 4 x 4 (quatro temperaturas de secagem e quatro periodos de armazenamento), em um delineamento inteiramente casualizado com sete repeticoes por tratamento e sete aves por unidade experimental. Cada amostra de milho substituiu em 40% da materia natural, uma racao-referencia. Foram realizadas analises de composicao quimica e energia bruta de cada amostra de milho. Foi determinada tambem a energia bruta das excretas. A composicao quimica e os valores de energia bruta (kcal/kg) das amostras de milho nao foram significativamente influenciados pela temperatura de secagem e pelo tempo de armazenamento. Entretanto, os valores de EMA e de EMAn foram influenciados pela temperatura de secagem e pelo tempo de armazenamento, isoladamente. Foi observado efeito quadratico para temperatura de secagem, com maiores valores de EMA e EMAn do milho nas temperaturas de 49 e 50oC, respectivamente, obtidos por equacao de regressao. Para o tempo de armazenamento, observou-se efeito linear decrescente para os valores de EMA e de EMAn. Observou-se que a temperatura de secagem e o tempo de armazenamento dos graos de milho reduziram os valores de EMA e de EMAn.

Determinação da Biodisponibilidade da Lisina Sulfato e Lisina HCl com Frangos de Corte

With the objective of determine the bioavailability of two lysine sources (lysine HCl and lysine sulfate), by a growth trial, 840 one day old male broiler chicks were placed in 56 boxes. Two basal diets were formulated to supply the birds nutritional requirements, one for the starting and the other for the growing period, respectively, deficient only in lysine, which were supplemented 0,08, 0,16 and 0,24% lysine of both lysine sources. Weight gain, feed intake, feed conversion, carcass yield, legs quarter yield, breast yield, breast meat yield and abdominal fat content were evaluated. Multiple linear regression and the slope ratio technique was used to estimate equations. The bioavailabity of lysine sulfate was obtained as a percentage of lysine HCl considered as 100% available. The equations that best estimated the bioavailability of the lysine sulfate (X2) related to lysine HCl (X1) were: Y = 544,72 + 439,62 X1 + 475,84 X2, R2 = 0,90, for weight gain (1 to 21 days of age); Y = 1824,63 + 1469,18 X1 + 1381,33 X2, R2 = 0,85, for weight gain from 01 to 42 days of age;11 Y = 1,9623 - 0,9043X1 ¾1,0235 X2, R2 = 0,83, for feed conversion (1 to 21 days of age); Y = 0,3766 + 0,5320 X1 + 0,4986 X2, R2 = 0,88, for breast yield (42 days of age) and Y = 0,2565 + 0,4685X1 + 0,4300 X2, R2 = 0,92 for breast meat yield with 42 days of age. The average bioavailability of lysine sulfate was 100,19%, showing that there was no difference (p > 0.05), in the bioavailability of the two lysine sources studied.

Crude protein level of pre-starter diets and nutritive solution for broilers

The objective of the present study was to evaluate the effect of dietary crude protein (CP) levels and the use of a nutritive solution via drinking water on the performance of pre-starter broilers. A total of 1,224 male Avian Farm chicks, from one to 40 days of age were used. Birds were distributed in a completely randomized experimental design with a 3 × 2 × 2 factorial arrangement, consisting of three initial body weights (low: 41 g, standard: 45 g and high: 49 g; two crude protein levels at the pre-starter phase (22 and 25% CP),with or without the addition of a nutritive solution, whose nutritional level was similar to the 25% CP pre-starter diet, at a concentration of 5% of the drinking water. Each treatment included six replicates and 17 chicks per experimental unit. At the end of the pre-starter phase, all hens received a diet with 22% CP until day 21 and a diet with 20% CP from the 21st to the 40th day. The use of the pre-starter diet with higher nutritional levels and the nutritive solution enhanced broiler performance. The early nutrient supply via drinking water resulted in better broiler performance and uniformity. However, birds with low initial body weight continued to present lower body weight at market age.

Lysine nutritional requirements of broilers reared in clean and dirty environments during the pre-starter and starter phases

A total of 3,760 Ross male broiler chicks were used in two trials, one in the pre-starter (1-11 days) phase and the other in the starter (12-22 days) phase. Birds were distributed in a completely randomized experimental design with a factorial arrangement of 5 digestible lysine levels × 2 environments (clean and dirty environment), with eight replicates per treatment. The following dietary digestible lysine levels used were: 1.06, 1.12, 1.18, 1.24 and 1.30% in the pre-starter phase, and 1.00, 1.06, 1.12, 1.18 and 1.24% in the starter phase. Minimal relation of digestible lysine:digestible methionine + cystine, threonine, tryptophan and arginine (72, 67, 19 and 108%, respectively) were maintained, as well as 2.088 and 2.002% of glycine+serine in the pre-starter and starter diets, respectively. Weight gain, feed intake and feed conversion were evaluated. In all phases, dietary digestible lysine levels significantly influenced broiler performance, and broilers reared in the clean environment presented better performance than those reared in the dirty environment. The recommended digestible lysine levels during the pre-starter and starter phases are 1.30 and 1.24% when broilers are reared in the clean enviroment and 1.26 and 1.165% in the dirty enviroment, respectively.