RESUMO -Foi conduzido um experimento para determinação da exigência nutricional de cálcio de 360 codornas japonesas fêmeas (peso médio inicial de 121,5 g), durante o período inicial de produção (56 a 171 dias de idade). As aves foram distribuídas em delineamento inteiramente casualizado, em esquema fatorial 6 x 4, com seis níveis de Ca na ração (1,6; 2,0; 2,4; 2,8; 3,2 e 3,6%) e quatro períodos experimentais de 28 dias. Cada tratamento foi constituído de seis repetições e a unidade experimental foi representada pela gaiola contendo dez aves. Não houve efeito significativo da interação níveis de Ca × períodos sobre nenhuma das variáveis avaliadas. Verificou-se, no entanto, aumento linear para produção de ovos, peso de ovo e espessura de casca. Houve ainda redução linear para conversão alimentar por massa de ovos e porcentagem de Ca na tíbia e efeito quadrático para massa de ovo, ganho de peso das aves, peso específico dos ovos, peso de casca e porcentagem de cinzas na tíbia. Observou-se que a produção e a massa de ovos obtidas com o nível de 3,2% de Ca foi 3,3 e 3,8% superiores, respectivamente, em valores absolutos, quando comparada àquela contendo 3,6% de Ca. A exigência de Ca estimada de codornas japonesas na fase inicial de produção variou de 3,0 a 3,6% na dieta, de acordo com os parâmetros avaliados. Recomenda-se o nível de 3,2% de Ca na dieta, que corresponde a um consumo diário de 882 mg de Ca/ave, ou de 87 mg de Ca/g de ovo, como exigência satisfatória para obtenção de melhor produção e de eficiente conversão alimentar (por massa e por dúzia de ovos) e para manutenção da qualidade dos ovos.Palavras-chave: Coturnix coturnix japonica, desempenho produtivo, níveis de cálcio, qualidade do ovo Determination of nutritional calcium requirement of Japanese quails in the initial production phase ABSTRACT -An experiment was conducted to determine nutritional calcium requirement of 360 Japanese female quails averaging initial weight of 121.5 g during the initial production phase (from 56 to 171 days of age). A complete randomized design with a 6 x 4 factorial arrangement (six Ca levels: 1.6, 2.0, 2.4, 2.8, 3.2, and 3.6% and four experimental periods of 28 days each) was used. Each treatment consisted of six replicates and a cage with ten birds, that was the experimental unit.No significant effect of Ca levels × periods interaction on any variable was detected. However, it was observed linear increase on egg production, egg weight and eggshell thickness and linear decrease on feed:egg mass ratio and Ca percentage in the tibia, and quadratic effect on egg mass, bird weight gain, egg specific weight, eggshell weight and ash percentage in the tibia. It was observed that egg production and mass obtained with the 3.2% Ca level was 3.3 and 3.8% greater, respectively, in absolute values, than the 3.6% Ca level. The estimated Ca requirement of Japanese laying quails during the initial production phase ranged from 3.0 to 3.6% in the diet, depending on the evaluated parameters. It is recommended the dietary Ca level of 3.2%, t...

RESUMO -Objetivou-se avaliar o fornecimento de misturas de extratos vegetais nas dietas de frangos de corte.Utilizaram-se 1.350 aves distribuídas em blocos casualizados, com seis repetições e cinco dietas, uma sem aditivos e outras quatro, cada uma contendo um dos aditivos: 10 ppm de avilamicina; 200 ppm de um produto contendo óleos essenciais de cravo, tomilho, canela e pimenta; 100 ppm de um produto comercial composto de óleos essenciais sintéticos de orégano e canela e óleo-resina de pimenta microencapsulados; 500 ppm de um produto comercial constituído de óleo de eucalipto, óleo essencial de canela-da-china, folhas de boldo-do-chile e sementes de feno-grego na fase inicial e 1.200 ppm nas fases de crescimento e final. Aos 21 e 42 dias, foram avaliadas as variáveis de desempenho e aos 44 dias de idade, as características de carcaça. Dos 27 aos 30 dias de idade, foi realizado o ensaio de metabolismo pelo método de coleta total de excretas e determinadas a energia metabolizável e a digestibilidade da proteína bruta das dietas. As dietas com misturas de extratos vegetais não tiveram efeito significativo sobre o desempenho se comparadas à dieta sem aditivo e à dieta com antibiótico. A ausência de desafio na criação e a utilização de dietas com ingredientes de alta digestibilidade podem ter contribuído para que as aves expressassem todo o seu potencial, tornando indetectável a melhora ocasionada pela inclusão de qualquer dos aditivos. Dietas contendo misturas de extratos vegetais promovem desempenho semelhante ao obtido com dietas contendo antibiótico.Palavras-chaves: aditivos, características de carcaça, desempenho, ensaio de metabolismo Plant extracts in diets for broilersABSTRACT -The trial was carried out to evaluate different blends of plants extracts in broilers diets. It was used 1,350 broilers distributed in a randomized block design with six replicates and five diets, one without additive and the four others, each containing one of the following additives: 10 ppm of avilamycin; 200 ppm of a product containing essential oils of carnation, thyme, cinnamon and microencapsulated capsicum; 100 ppm of a product containing essential oils of synthetic cinnamaldehyde and carvacrol and capsicum oleoresin microencapsulated; 500 ppm of a commercial product containing eucalypt oil, essential oil of Chinese cinnamon, leaves of Chilene boldo and seeds of fenu-Greek at the initial phase and 1200 ppm in the grower and finisher phases. Performance parameters were evaluated at 21 and 42 days of age and the carcass characteristics at 44 days of age. From 27 to 30 days of age, it was carried out the metabolism trial trough total excreta collection method and metabolizable energy and the crude protein digestibility of the diets were determined. The diets with plant extract blends had no significant effect on the performance when compared to diet without additives or diet with avilamycin. The lack of challenge in the experimental facilities and the use of diets with high digestibility ingredients might have contributed to broil...

RESUMO Evaluation of corn with different densities for broilersABSTRACT -The objective of this work was to determine the nutritional value of corn of four different qualities, obtained by stratification in densimetric table, for broilers at different ages. The corns were designed as: MDA -high density corn; MDI -medium density corn; MDB -low density corn and MDO -original density corn, composed of 25% MDA, 50% MDI and 25% MDB. Three biological assays were carried out by using the traditional total excreta collection method for determination of nitrogen corrected apparent metabolizable energy (AMEn). The first metabolism assay was carried out with Cobb chicks at 14 to 17 days of age, the second assay with chicks at 25 to 28 days of age and the third with chicks at 38 to 41 days of age. Chemical analyses were made for determination of the nutritional profile, classification of the grains according to density and comparison by estimates of energy value prediction equations. The values of AMEn of corns of different qualities (MDA, MDI, MDB and MDO) determined in broilers in initial phase were: 3562, 3382, 3198 and 3357 kcal/kg for growth phase and for final phase they were 3576, 3555, 3229 and 3416 kcal/kg and for the finish phase they were 3610, 3554, 3354 and 3585 kcal/kg, respectively. These results prove that significant energy losses of the lowest quality corns and the efficiency of the densimetric Zootec., v.40, n.7, p.1554-1561, 2011

RESUMO -O objetivo neste estudo foi avaliar os efeitos de um complexo enzimático, composto por protease, xilanase e amilase, associado ou não a betaína em dietas para frangos de corte sobre o desempenho das aves e a análise econômica. Pintos machos da linhagem Cobb 500 (924), com peso médio inicial de 45,8 g, foram alimentados com quatro dietas, cada uma com sete repetições, em um delineamento inteiramente casualizado. Cada unidade experimental continha 33 aves. As dietas foram:controle -rações à base de milho e farelo de soja; enzimas -rações acrescidas de enzimas (protease, xilanase e amilase); betaína -rações acrescidas de betaína natural; enzimas + betaína -rações acrescidas de enzimas e betaína. Evaluation of an enzymatic complex and natural betaine in rations for broilers chickens raised in a commercial poultry houseABSTRACT -The objective of this study was to evaluate the effects of an enzymatic complex composed of protease, xylanase and amylase, associated or not to betaine in diets for broiler chickens on the performance of birds and economical analysis. It was used Cobb 500 male broiler chicks (924) at average initial weight of 45.8 g fed four diets, each one with seven replicates, in a completely randomized design. Each experimental unit had 33 birds. The diets were: control -corn and soybean meal-based rations; enzymes -rations added with enzymes (protease, xylanase and amylase); betaine -rations added with natural betaine; enzymes + betaine -rations added with enzymes and betaine. In the period from 1 to 7 days, the addition of enzymes or betaine into the rations did not influence performance traits. In the period from 1 to 21 days of age, birds fed diets with enzymes + betaine showed lower average feed intake when compared to those diets only with enzymes. However, average weight gain and feed conversion were similar. Diets with enzyme or betaine did not influence performance of the birds compared to control diet. Likewise, in the period from 1 to 35 days, performance of the birds fed diets with enzymes and betaine was similar to the control group. At 41 days of age, broilers fed diets with enzyme or betaine showed performance similar to the control group, so, the additives used had the expected effects. However, combination of the additives did not show the same efficiency. There was no significant influence of diets in the feed cost. Among the evaluated additives, only enzyme and betaine do not affect performance of the birds.