ABSTRACT The main objective of this study was to evaluate the effect of placement time on the performance of broiler chickens and the development of their gastrointestinal tract. Two methodologies for measuring broiler performance were compared, one considering day of pulling as the first day, the other considering day of placement as the first day. A total of 1,056 one-day old male Cobb® 500 broiler chicks were subjected to treatments of different placement times after pulling from the hatchery: 3, 24, 48, and 72 h. The studied traits were: feed intake, body weight, feed conversion, viability, and gastrointestinal tract development. When day of pulling was considered the first day, feed intake and body weight at 39 days decreased as placement time increased. However, when day of placement was considered the first day, fasting up to 72 h did not have any negative effect on broiler performance at 39 days post-placement. Placement time did not affect yolk sac utilization or liver weight. At nine days post-placement, weights of gizzard + proventriculus, pancreas, and small intestine increased with increasing placement time. At seven days of age, there was no effect of placement time on villus height or crypt depth. It is possible to place broiler chicks up to 72 h post-hatching with no negative effects when day of placement is considered the first day for evaluating broiler performance.

ABSTRACT The objective of this study was to ascertain the influence of different dietary fiber sources and the usage of xylanase on diet of commercial layers and their influence on productive performance, egg quality, and digestive organ biometry. A total of 864 Lohmann® White hens was fed diets with three different fiber sources (wheat bran, soybean hull, or coffee husk) with or without xylanase inclusion (concentration of 160,000 BXU/g) in a 3×2 factorial arrangement, with six replicates of 24 birds each, from 25 to 44 weeks of age. There were no interactions between dietary fiber and xylanase inclusion. The enzyme supplementation did not influence any parameters evaluated. There were dietary fiber effects on body weight gain, viability, egg weight, eggshell quality, yolk pigmentation, and liver and gizzard relative weights. Wheat bran, soybean hull, and coffee husk can be used in laying hen diets without detrimental effect on productive performance. The enzyme used had no effect on the performance and eggshell quality of laying hens.

Resumo: O objetivo deste trabalho foi avaliar o efeito de diferentes procedimentos de desinfecção alternativos à fumigação com formaldeído sobre a redução da contagem microbiana e a qualidade de casca de ovos de matrizes Cobb de 42 semanas de idade. Um total de 10.080 ovos limpos coletados dos ninhos foi distribuído de maneira aleatória, em delineamento de blocos ao acaso, entre os seguintes tratamentos: fumigação com 13,33 g m-3 de paraformaldeído, fumigação com 5-10 ppm de ozônio, 6,36 mW cm-2 de irradiação de luz UV-C, pulverização com 1,56% de peróxido de hidrogênio, pulverização com 0,13% de ácido peracético, pulverização com água (controle úmido) e sem desinfecção (controle seco). Por tratamento, foram coletadas oito amostras de quatro ovos cada uma, momentos antes e após as desinfecções, para contagem de Enterobacteriaceae e bactérias mesófilas aeróbicas totais da casca. Somente os ovos submetidos aos tratamentos com formaldeído e UV apresentaram redução significativa nas contagens de bactérias mesófilas aeróbicas totais, quando comparados aos do grupo controle seco. Os tratamentos não influenciaram a espessura e a resistência da casca. A exposição de luz UV é eficaz em reduzir a contagem microbiana da casca de ovos de matrizes de 42 semanas de idade, sem afetar sua qualidade, e pode ser considerada alternativa ao uso de formaldeído para desinfecção.

Abstract: The objective of this work was to evaluate the effect of different disinfection procedures as alternatives to formaldehyde fumigation on eggshell microbial load and quality of eggs from a 42-week-old Cobb commercial breeder flock. A total of 10,080 clean eggs collected from the nests were randomly distributed in a randomized complete block design, among the following treatment groups: 13.33 g m-3 formaldehyde fumigation, 5-10 ppm ozone fumigation, 6.36 mW cm-2 UV-C light irradiation, spraying with 1.56% hydrogen peroxide, spraying with 0.13% peracetic acid, spraying with water (wet control), and no disinfection procedure (dry control). Per treatment, eight samples of four eggs each were collected before and after the disinfection procedure, in order to count the number of Enterobacteriaceae and total aerobic mesophilic bacteria on the eggshell. Only eggs subjected to the formaldehyde and UV treatments showed a significant reduction in total aerobic mesophilic bacterial count on the eggshell, when compared with those of the dry control group. Treatments did not affect eggshell thickness and resistance force. UV light exposure is effective in reducing microbial load on 42-week-old breeder flock eggshells, without affecting their quality, and can be considered an alternative to formaldehyde disinfection.

ABSTRACT This study was conducted to evaluate the effect of two levels of vitamin D3 with or without 1,25- dihydroxycholecalciferol (1,25(OH)2D3) on live performance and bone quality of broiler chickens. For that, we used a completely randomized design in a 2 × 2 factorial arrangement, with eight replicates of 30 Cobb®500 male broiler chicks each (n = 960). The two levels of vitamin D3 and the addition or not of 0.5 μg 1,25(OH)2D3/kg were considered as main factors. The vitamin D3 levels were: 2500/2000 IU/kg and 1250/1000 IU/kg for the starter (1 to 21 days) and grower (22 to 40 days) phases, respectively, with the first representing the levels used in industry (100%) and the second, a reduction in 50% of those levels. The 1,25(OH)2D3 source was Solanum glaucophyllum. On days 21 and 40, one broiler per replicate was killed and long bones were removed for analyses of mineral percentage, bone mineral density, biomechanical properties, and morphology. No significant differences were found related to vitamin D3 levels and the addition or not of 1,25(OH)2D3 for live performance, mineral percentage, strength, stiffness, and morphology. Toughness was lower when 1,25(OH)2D3 was used at 21 days, but this effect was not observed at 40 days of age. Bone mineral density was greater when 100% of vitamin D3 was used at 40 days of age. The reduction of up to 50% of vitamin D3 levels is sufficient to ensure performance and bone development of broilers at 21 and 40 days of age. The inclusion of 0.5 μg 1,25(OH)2D3/kg in addition to diets with sufficient levels of vitamin D3 shows no effect on the improvement of those parameters at the same ages.

Foram avaliados os efeitos de diferentes dietas lipídicas na composição de ácidos graxos (AG) de ovos produzidos por poedeiras Dekalb de 20 e 54 semanas de idade. As poedeiras foram submetidas a três tratamentos definidos de acordo com a fonte lipídica adicionada nas rações: óleo de soja, sebo bovino e ração controle (sem adição de óleo). O delineamento experimental foi inteiramente casualizado em arranjo fatorial 3x2 (três tratamentos e duas idades das galinhas). Foram analisadas as composições em ácidos graxos das gemas dos ovos produzidos pelas poedeiras. O perfil de ácidos graxos das gemas dos ovos, produzidos pelas aves alimentadas com rações contendo óleo de soja, apresentaram na sua composição grande quantidade de ácidos graxos poliinsaturados (PUFA) ômega 6 (n-6) and Omega 3 (n-3) (23,55; 2,30% respectivamente), enquanto as gemas dos ovos de poedeiras que receberam sebo bovino apresentaram maiores porcentagens de AG monoinsaturados (47,53%) na sua composição, comparados com dieta contendo óleo de soja (47,53%) e dieta controle (38,72%). As porcentagens de gordura trans presente nas gemas dos ovos de todos os tratamentos foram consideradas muito baixas (0,91; 0,11; 0,05%). Poedeiras novas são mais eficientes em depositar AG n-3 (1,40%), especialmente C22:6 (0,76%) na gema do ovo, com melhor razão n6:n:3 (13,97) comparado com poedeiras velhas (1,35; 0,72; 14,81% respectivamente). Com base nesses resultados, foi concluído que a quantidade de ácidos graxos presentes na gema dos ovos podem ser modificadas de acordo com as fontes de lipídios oferecidas nas dietas e que, independente da adição de diferentes fontes lipídicas na ração e da idade das galinhas, as gemas dos ovos possuem quantidades insignificantes de gorduras trans.

The effects of different dietary lipids on the fatty acid profiles of eggs produced by 20 and 54 wk old Dekalb laying hens were investigated. Laying hens were subjected to three defined treatments according to the source of lipid added to their diets: soybean oil, beef tallow, and a control diet (without the addition of oil). The experimental design was in a 3x2 factorial arrangement (three treatments and two different ages). The fatty acid composition of the yolks in the eggs produced by the laying hens was analyzed. The eggs produced by laying hens on the soybean oil diet had a large amount of polyunsaturated fatty acids (PUFA) omega-6 (n-6) and omega-3 (n-3) in their yolks (23.55, 2.30% respectively), whereas egg yolks from hens who were given beef tallow had higher percentages of monounsaturated fatty acids (47.53%) compared to soybean oil (47.53%) and the control diet (38.72%). The percentages of trans fats present in the egg yolks in all treatments were considered very low (0.91; 0,11; 0.05%). Young layers are more efficient at depositing n-3 fatty acids (1.40%), specially C22:6 (0.76%) with the best ratio n6:n-3 (13.97) compared to old layers (1.35; 0.72; 14.81% respectively). Based on these results, it was concluded that the amount of fatty acids present in the egg yolks can be modified by the sources of lipids included in the diet and that independent of the sources of lipid in the diet and the age of the chicken, egg yolks have insignificant amounts of trans fatty acids.

Avaliaram-se os efeitos dos níveis de energia, lisina, metionina + cistina na ração sobre o desempenho e os rendimentos de carcaça e cortes de frangos de corte. O delineamento experimental foi o inteiramente ao acaso, em esquema fatorial (3 × 2), composto de seis tratamentos e oito repetições (quatro para machos e quatro para fêmeas). Os tratamentos foram definidos pelos níveis de energia (baixo, médio e alto), lisina e metionina + cistina (padrão ou 10% superiores ao recomendado) e pelo período de criação (1 a 45 dias de idade). Em frangos machos, níveis médios de energia (3.000, 3.100 e 3.200 kcal/kg, respectivamente, nas rações inicial, de crescimento e final) e níveis normais de aminoácidos proporcionam maior ganho peso aos 45 dias de idade, no entanto, para obtenção de maior rendimento de peito, o nível mais alto de aminoácidos é mais recomendável. Em fêmeas, para maior ganho de peso até os 40 dias de idade, devem ser associados níveis médios de energia e níveis mais altos de aminoácidos.

The effects of dietary energy, lysine and methionine + cystine levels on performance, carcass and cuts yields of male and female broiler chickens were evaluated. The experiment was analyzed as a completely randomized experimental design in a 3 × 2 factorial arrangement composed by six diets and eight replications (four males and four females). The diets consisted of energy (low, middle and high) and lysine and methionine + cystine (standard and + 10%) levels and of raising period (1 to 45 days old). Male broilers fed diets with 3,000, 3,100 and 3,200 kcal/kg, respectively, in the initial, growing and standard levels of amino acids showed better weight gain at 45 days old, however, for the best breast yield, the highest amino acid level was the most indicated. Middle energy and high amino acids levels are indicated for greater weight up to 40 days old, in females.

Um experimento foi realizado para se determinar as exigências de lisina de suínos machos castrados, na fase de terminação tardia, avaliando-se os efeitos de diferentes níveis de lisina da ração sobre o desempenho e características de carcaça dos animais. Utilizaram-se 50 suínos híbridos comerciais (AG-PIC 412 X C-22), com peso inicial de 95,39 ± 0,85 kg e final de 122,29 ± 3,02 kg, distribuídos em delineamento experimental de blocos ao acaso, com cinco tratamentos (0,5; 0,6; 0,7; 0,8 e 0,9 % de lisina total), cinco repetições e dois animais por unidade experimental. Os blocos foram formados no tempo e na distribuição dos animais, dentro de cada bloco, foram adotados como critérios o parentesco e o peso inicial dos animais. Foi observado efeito quadrático dos níveis de lisina sobre o ganho de peso diário, conversão alimentar, consumo de lisina diário e taxa de deposição de carne magra diária. Não houve efeito dos tratamentos sobre o consumo de ração diário, espessura de toucinho no ponto P1, espessura de toucinho no P2, profundidade de lombo, porcentagem de carne magra, rendimento de carcaça, comprimento de carcaça pelo método brasileiro, comprimento de carcaça pelo método americano, espessura de toucinho na 10ª costela, espessura de toucinho na última costela e rendimento de pernil. Concluiu-se que a exigência de lisina total para suínos machos castrados selecionados para deposição de carne magra na carcaça, de 95 a 122 kg, é de 0,72 %, correspondendo a um consumo diário de 25,46 g.

An experiment was conducted to determine lysine requirements of barrows, during the late-finishing phase, to evaluate the effects of lysine levels on performance and carcass characteristics of animals. Fifty hybrid pigs (AG-PIC 412 X C-22), averaging 95.39 ± .85 kg initial weight and 122.29 ± 3.02 kg final weight were used in a completely randomized block design with five dietary treatments ranging from .50 to .90% of total lysine (.10% increments), five replicates and two animals per experimental unit. Initial body weight and relationship coefficient were used to establish the blocks. Quadratic effect of lysine level on average daily gain, feed conversion, daily lysine intake and daily lean gain was observed. There was no effect of treatments on daily feed intake, P1 backfat thickness, P2 backfat thickness, loin depth, lean percentage, carcass yield, carcass length, carcass length Brazilian method, 10th rib fat depth, last rib fat depth and ham percentage. Based on these results, it was concluded that the total dietary lysine requirement for barrows with high genetic potential for lean gain, from 95 to 122 kg, is 0.72% total lysine, which corresponds to approximately 25.46 g/day of lysine intake.