Germano Augusto Jerônimo do Nascimento

Composição química e energia metabolizável de híbridos de milho para frangos de corte

The values of chemical composition and metabolizable energy of 45 hybrid corns were determined in four trials with growing chickens. A total of 1,225, nineteen days old male chicks were used: 350 in the trials 1, 2 and 3 and 175 in trial 4. In the trials 1, 2 and 3 the treatments consisted of 13 test diets, being 13 corn varieties, and the reference diet in each trial. Trial 4 consisted of 7 treatments, being 6 test diets (corn varieties) and the reference. The hybrid corns, replaced 40% of the reference diets in all the trials.. A completely randomized design with five replicates of five birds per cage was used. The diets and water were offered ad libitum for a 7-day period, being four days for adaptation and three for days for excreta collection. A variation of 32% in crude protein - CP (7.79% vs. 11.45%, dry matter basis) was found. The values of gross energy (GE) presented a variation of 5.2%. The higher value observed was 4,668 kcal and the lower value 4,425 kcal/kg. The average value for corrected apparent metabolizable energy (AMEn) was 3,744 kcal/kg, with a variation of 15.15% (3,405 to 4,013 kcal/kg). However, it was observed that the two hybrids presenting this variation (608 kcal AMEn/kg DM) had similar GE values (3914 and 3931 kcal GE/kg of DM; 0.36% variation). This variation in the AMEn can possibly be accounted on the coefficient of gross energy metabolization which was 75% for the hybrid with the lowest AMEn and 88% for the hybrid with the highest AMEn. Despite of corn being an energy source , the evaluation of its CP content is important due to the considerable variation in the protein values of the different hybrids found currently. The same is valid for the energy values.

Equações de predição para estimar os valores energéticos de alimentos concentrados de origem vegetal para aves utilizando a metanálise

The present study was carried out to obtain prediction equations to estimate the metabolizable energy values (AMEn) of concentrate feeds of plant origin commonly used in poultry diets, using the meta-analysis principle. A data collection review was made of the studies carried out in Brazil to catalogue information on the metabolizable energy values and chemical composition of the feeds (CP - crude protein; EE - ether extract; ash; CF - crude fiber; NDF - neutral detergent fiber; ADF - acid detergent fiber), to obtain the prediction equations to estimate the metabolizable energy of these feeds, using their chemical composition. The following effects were considered: sex at three levels (male; female and mixed); age at four levels (1st and 2nd week of life; 3rd and 4th week; 5th and 6th seek; above or indefinite) and the methodology used in the metabolism assay at two levels (total collection of excreta - TC and forced fed plus TC). The factorial arrangement among the effects (3 × 4 × 2), totaling up to 24 groups, was submitted to the weighed least squares analysis. The Stepwise procedure was adopted to study the association among the variables, and then, the Proc Reg (SAS) as used to fit the multiple linear regression model. Two equations were a better fit to estimate the metabolizable energy of the concentrate feeds, metabolizable energy = 4101.33 + 56.28EE 232.97ash 28.86NDF + 10.42ADF (R² = 0.84) and metabolizable energy = 4095.41 + 56.84EE 225,26ash 22.24NDF (R² = 0.83). It was observed that the variables neutral detergent fiber and acid detergent fiber were important and that they cannot be disregarded, since their removal from the model reduced the determination coefficient from 84% and 83% to 70%.

Níveis de proteína bruta e energia metabolizável na produção e qualidade dos ovos de poedeiras da linhagem Lohmann Brown

O experimento foi realizado no Setor de Avicultura do Departamento de Zootecnia da Universidade Federal da Paraiba, com o objetivo de avaliar o desempenho de 324 poedeiras Lohmann Brown submetidas a diferentes niveis proteicos e energeticos entre a 43a e 55a semana de idade. As aves foram distribuidas em delineamento experimental inteiramente casualizado num esquema fatorial 3x3, sendo 3 niveis proteicos (15,50, 16,50 e 17,50%) e 3 niveis energeticos (2700, 2800 e 2900 Kcal EM/kg), com 6 repeticoes e 6 aves por unidade experimental. As variaveis avaliadas foram producao de ovos, massa de ovos, conversao alimentar por massa de ovos, peso do ovo, peso do albumen, peso da gema e peso da casca e suas respectivas porcentagens. Os niveis de proteina bruta e energia metabolizavel nao influenciaram significativamente (P>0,05) nenhum dos parâmetros estudados. Os niveis de proteina bruta e energia metabolizavel apresentaram efeito linear (P<0,05) apenas para as variaveis, peso e porcentagem do albumem e da casca, porem nao houve interacao. Conclui-se, portanto, que os melhores niveis de proteina e energia metabolizavel para a producao de poedeiras Lohmann Brown, entre o periodo de 43 a 55 semanas de idade, foram 17,50% de PB e 2900 Kcal de EM/kg para melhor peso e porcentagem de albumen e de 15,50% de PB e 2700 Kcal de EM/kg para melhor peso e porcentagem de casca..

Níveis de lisina para frangos de corte nos períodos de 22 a 42 e de 43 a 49 dias de idade

Foram realizados dois experimentos para determinar a exigencia de lisina total para frangos de corte Ross, macho, no periodo de 22 a 42 e de 43 a 49 dias de idade. Utilizou-se em cada experimento, 900 frangos com peso medio inicial de 764 g ± 35 g aos 22 dias e de 2520 ± 73 g aos 43 dias de idade. As aves foram distribuidas em um delineamento inteiramente casualizado, com seis tratamentos, seis repeticoes e 25 aves por unidade experimental. Os tratamentos foram constituidos de seis niveis lisina, de acordo com a fase. As exigencias nutricionais minimas, exceto para lisina, foram atendidas. As variaveis avaliadas foram consumo de racao, ganho de peso, conversao alimentar, rendimento de carcaca e dos principais cortes, porcentagem de gordura abdominal, coracao, figado e moela, sendo as exigencias de lisina estimadas por modelos de regressao. Considerando os dados obtidos, as exigencias nutricionais de lisina total foram estimadas em 1,111% para o maximo desempenho, no periodo 22 a 42 dias de idade e de 1,044% para o maximo desempenho e rendimento de carcaca e peito, no periodo de 43 a 49 dias de idade.

Níveis de metionina + cistina para frangos de corte nos períodos de 22 a 42 e de 43 a 49 dias de idade

Two experiments were conducted with the objective of evaluating the methionine + cystine (Met + Cis) requirements, for Ross broilers, males, from 22 to 42 and 43 to 49 days old. Nine hundred broilers averaging initial body weight of 0.800 kg at 22 days old and 2.540 kg at 43 days old were used in each experiment and allotted to a completely randomized experimental design, with six treatments, six replicates and 25 birds for experimental unit. The treatments consisted of six different sinthetic methionine levels (0.00, 0.04, 0.081, 0.121, 0.162 and 0.202%), corresponding to the levels of 0.664, 0.704, 0.744, 0.784, 0.824 and 0.864% and 0.603, 0.643, 0.683, 0.723, 0.763 and 0.803% dietary total methionine + cystine, for the phases from 22 to 42 and from 43 to 49 days old, respectively. Feed intake, body weight gain, feed:gain ratio, carcass yield and the prime cuts yield were evaluated. The methionine + cystine requirements were estimated by regression models. Considering the performance data, the nutritional requirements of total methionine + cystine were 0.823% for high performance and breast yield values, in the period from 22 to 42 days old, and 0.727% for the high performance and low requirements of abdominal fat, in the period from 43 to 49 days old.

Níveis de lisina para frangos de corte nos períodos de 22 a 42 e de 43 a 49 dias de idade, mantendo a relação metionina + cistina

Two experiments were conducted with the objective of evaluating the lysine requirements for Ross broilers, males, from 22 to 42 and 43 to 49 days old, maintaining 71% met + cys:lys ratio. Nine hundred broilers averaging initial body weight of 780 g at 22 days old and 2.556 g at 43 days old were used in each experiment and allotted to a completely randomized experimental design, with six treatments, six replicates and 25 birds by experimental unit. The treatments consisted of six different synthetic lysine levels, according to the phase and the fixed ratio. Minimum nutrition requirements, except lysine and met + cys, were met. Feed intake, body weight gain, feed gain ratio, carcass yield and the prime cuts yield were evaluated. The lysine requirements were estimated by the regression models. Considering the performance data, the nutritional requirements of total lysine were of 1.140% for maximum performance, in the period from 22 to 42 days old, and of 1.024% for maximum performance and carcass and breast yield, in the period from 43 to 49 days old.

Limestone particle size and artificial light for laying hens in the second laying cycle

The experiment was conducted to evaluate the effects of limestone particle size and the use of artificial light for laying hens in the second laying cycle. We used 240 Hisex White laying hens at 82 weeks of age in a completely randomized design in a 5 × 2 factorial arrangement, resulting in 10 treatments with 4 replicates of 6 birds. The variables were the five particle sizes obtained by increasing the proportion of thick limestone (0, 25, 50, 75 and 100%) compared with thin limestone and two lighting programs: with and without artificial light. Limestone particle size and light did not affect performance or egg quality. However, there were changes in bird feeding schedule throughout the day as a response to the lighting program. Bone quality, density and mineral content of the tibia were not affected by the treatments, but limestone particle size had a quadratic effect of on bone deformity and strength, obtaining maximum inclusion points with 63% and 59% of thick limestone, respectively. The use of large particles of limestone in the diet and the use of a lighting program does not influence the performance and quality of the eggs of laying hens in the second production cycle, but the use of a proportion of 63.3 g of average particle size (0.60 mm) replacing the fine limestone (0.23 mm) per 100 g of total limestone added to the diet improves bone quality in these birds.

Desempenho de frangos de corte nas fases de crescimento e final alimentados com rações contendo soja integral extrusada em diferentes temperaturas

The effects of full-fat extruded soybean at different temperatures (FES) on performance of broiler chickens were evaluated in this trial. Isonutritive diets were formulated to meet broiler requirements in the growing (22 - 35 days old) and finishing (36 - 45 days old) phases. The experimental treatments consisted of four soybean extrusion temperatures (125, 130, 135 and 140oC) with nine replicates of 30 birds. The variables investigated were: feed intake, weight gain, feed:gain ratio and carcass composition (leg yield, breast meat yield and abdominal fat). In both phases, no significant effect of the treatments on the variables was detected. Soybean extruded at temperature of 125 to 140oC can be used in broiler chickens diets after 22 days old.