This study evaluated non-genetic factors and calculated heritability estimates of direct and maternal effects for growth traits in Nellore cattle raised in southern Brazil. Performance records of 4170, 1538, 3139, 1830, and 1151 calves born from 2005 to 2011 were analyzed for birth weight (BW), adjusted120-day weight (W120), adjusted 205-day weight (W205), adjusted365-day weight (W365), and adjusted 550-day weight (W550), respectively. The components of (co)variance used to calculate heritability estimates were determined by Derivative-Free Restricted Maximum Likelihood using the MTDFREML software. Contemporary groups were included in the model as fixed effects, and direct and maternal effects, permanent environmental effects, and residual errors were included as random effects. Phenotypic correlations were estimated using the PROC CORR procedure from SAS. Overall means for BW, W120, W205, W365, and W550 were 38, 138, 201, 270, and 376 kg, respectively. Heritability estimates for direct and maternal effects were 0.17 ± 0.04 and 0.11 ± 0.03 (BW), 0.14 ± 0.03 and 0.03 ± 0.04 (W120), and 0.17 ± 0.04 and 0.09 ± 0.03 (W205). Genetic, phenotypic, and environmental correlations were 0.79, 0.44, and 0.32 for BW and W120, 0.79, 0.39, and 0.26 for BW and W205, and 0.96, 0.74, and 0.75 for W120 and W205. The results indicate that selection for pre-weaning weight would be more efficient using W205, and genetic correlation coefficients indicate that selection at any age should produce a positively correlated response at older ages. Genetic, phenotypic, and environmental correlation coefficients between W365 and W550 were 0.99, 0.75, and 0.76, respectively. Selection for adjusted 550-day weight should produce the greatest genetic gains. Genetic correlation coefficients between weight traits indicate that selection for weight at older ages, which could help reduce the number of weighings and increase accuracy of selection at younger ages, produces gains at older ages. Key words: Beef cattle. Body weight. Correlation. Direct heritability. Maternal heritability. ResumoCom o objetivo de estudar os fatores ambientais e estimar os parâmetros genéticos, para os efeitos diretos e maternos, para as características de crescimento, foram utilizadas 4170, 1538, 3139, 1830 e 1151 observações de peso ao nascer (PN), peso ajustado aos 120 dias de idade (P120), peso ajustado aos 205 dias de idade (P205), peso ajustado aos 365 dias de idade (P365) e peso ajustado aos 550 dias (P550), de bovinos da raça Nelore nascidos no município de Amaporã-PR. As médias estimadas para PN, P120, P205, P365 e P550, foram 38 kg, 138 kg, 201 kg, 270 kg e 376 kg, respectivamente. Os componentes de (co) variância utilizados para estimar as herdabilidades foram obtidos por meio do programa MTDFREML, o modelo utilizado considerou o efeito fixo do grupo de contemporâneos, o efeito da idade da vaca ao parto como covariável, além dos efeitos aleatórios genéticos aditivo direto e materno e o efeito de ambiente permanente. As correlações fenotípicas foram estim...

As degradabilidades in situ da matéria seca (MS), matéria orgânica (MO), proteína bruta (PB), fibra em detergente ácido (FDA) e da fibra em detergente neutro (FDN) do caroço de algodão integral (CAI), farelo de soja (FS), grão de girassol (GG), torta de nabo forrageiro (TN) e do milho triturado (MT) foram determinadas com a incubação de sacos de náilon no rúmen de cinco bovinos ½ sangue Simental-Zebu. As degradabilidades efetivas (DE) da matéria seca (MS) e da proteína bruta (PB) a taxa de passagem de

The present study objective was to determine the intake and digestibility, nitrogen balance and ruminal fermentation parameters in sheep fed diets containing levels of substitution of soybean meal for sunflower cake. The diets consisted of five levels of protein soybean meal (0, 25, 50, 75 and 100 %) by sunflower cake. Diets were formulated with 12.6% CP, respecting the roughage:concentrate ratio of 40:60, as source roughage was used hay Tifton-85 and as food concentrates used were: corn, soybean meal, sunflower cake and premix mineral vitaminic. Five lambs crossbred castrated with average weight of 29.64 ± 2.94 kg were used, distributed in latin square 5 x 5. There were no differences in intake dry matter (DM), organic matter (OM), crude protein (CP), neutral detergent fiber (NDF) and total digestible nutrients. The intake of ether extract (EE) and non-fiber carbohydrates (NFC) were increased linearly. For intake of total carbohydrates (TC) was observed equation linear in relation to body weight and metabolic weight and quadratic when expressed in g day -1 with peak in 377.1 g kg -1 replacement of soybean meal by sunflower cake. There were no differences in digestibility DM, OM, CP, NDF, NFC and TC. There was a linear increase in the digestibility of ether extract (EE). The intake, feces, urinary and retained nitrogen were not influenced by levels of substitution of soybean meal by sunflower cake in the diets. For the pH of liquor ruminal there was no difference for the different levels of substitution of soybean meal by sunflower cake. However, ruminal pH differed with respect to collection time for all experimental diets. There was no effect on diets and sampling time for concentration of NH 3 -N. It was concluded that the sunflower cake can be used as an alternative food to replace soybean meal up to 100% in concentrate mixture unless there are changes in the rumen parameters, balance of nitrogen, intake and nutrient digestibility. Key words: Co-products, oilseed, ruminants ResumoObjetivou-se com este estudo, determinar o consumo e digestibilidade dos componentes nutritivos, balanço de nitrogênio e os parâmetros de fermentação ruminal em borregos alimentados com rações contendo diferentes teores de torta de girassol em substituição ao farelo de soja. Os tratamentos consistiram em cinco níveis de substituição da proteína do farelo de soja (0; 25; 50; 75 e 100 g kg -1 MS) pela torta de girassol. As rações foram formuladas com 12,6% PB respeitando-se uma relação volumoso:concentrado de 40:60, tendo como fonte volumosa o feno de Tifton-85 e ração suplementar formuladas com milho, farelo de soja, torta de girassol, mistura mineral e vitamínica. Foram utilizados cinco borregos sem raça definida, castrados, com peso vivo médio de 29,64 ± 2,94 kg, distribuídos em quadrado latino 5 x 5. Não houve diferenças nos consumos de matéria seca (MS), matéria orgânica (MO), proteína bruta (PB), fibra em detergente neutro (FDN) e nutrientes digestíveis totais (NDT). O consumo de extrato etéreo (EE) e carboidratos não fi...

ResumoAvaliaram-se concentrados proteicos através da composição bromatológica, fracionamento de carboidratos e proteínas e cinética da degradação in vitro em líquido ruminal de bovinos e ovinos. Foram utilizados farelos de soja (FS) e de algodão com casca (FA), grão seco destilado de milho (DDG), tortas de girassol (TG) e de crambe (TC). Determinou-se a composição bromatológica e os fracionamentos de carboidratos (A+B1, B2 e C) e de proteínas (A, B1+B2, B3 e C). O ensaio de degradabilidade in vitro foi realizado com líquidos ruminais provenientes de três ovinos e três bovinos. Os alimentos foram incubados e as leituras da produção de gases foram realizadas nos tempos 1, 2, 3, 4, 5, 6, 9, 12, 18, 24, 30, 36, 48, 60, 72, 84, 96 e 144 horas pós-incubação. Para a avaliação do fracionamento empregou-se delineamento inteiramente casualizado e para a produção de gases empregou-se esquema fatorial 4 x 2 (quatro alimentos e duas espécies de animais). As médias foram comparadas pelo teste Tukey. Para avaliação da cinética de fermentação ruminal foi utilizado o modelo de Gompertz. O FS apresentou maior quantidade de PB e o DDG apresentou a maior quantidade de CHT em relação aos demais alimentos. A TC apresentou maior quantidade de fração A da PB. Na degradação o FS e o DDG produziram maiores quantidades de gases. Utilizando o líquido ruminal de bovinos, obteve-se maior produção de gases em relação aos ovinos. Entre os alimentos avaliados o farelo de soja firmou-se como a fonte proteica mais interessante à alimentação de ruminantes.Palavras-chave: carboidratos, coprodutos, líquido ruminal, proteína. AbstractIt was evaluated protein concentrates by chemical composition, carbohydrates and proteins fractioning, and in vitro degradation kinetics in bovine and ovine ruminal liquid. Soybean meal (SM), shelled cottonseed meal, dried corn distillers grains (DDG), sunflower cake, and crambe cake (CC) were used. Their chemical composition, and fractioning of carbohydrates (A + B1, B2 and C) and protein (A, B1 + B2, B3, and C) were determined. The in vitro degradability was evaluated using ruminal liquid from three bovines and three ovines. The ingredients were incubated and gas production readings were performed on 1, 2, 3, 4, 5, 6, 9, 12, 18, 24, 30, 36, 48, 60, 72, 84, 96 and 144 hours after incubation. For the fractioning trial, a completely randomized design were used and for the gas production trial a 4x2 factorial scheme (four food and two species of animals) were utilized. The obtained means were compared by the Tukey test. To evaluate the kinetics of ruminal fermentation, the model of Gompertz was used. SM had higher amounts of CP in comparison to other foods, and the DDG showed the highest amount of total carbohydrates. The CC presented the highest A fraction of the CP. In the degradation trial, SM and DDG produced higher amounts of gas(mL g -1 ). The bovine's ruminal liquid provided higher gas production than the ovine's liquid. Among the foods evaluated, soybean meal has established itself as the best protein source to r...

ABSTRACT. This study aimed to assess different microbial additives, regarding the efficiency of aerobic stability in corn silages. The corn hybrid used for silages production was the DKB 310. . The experimental design was completely randomized with five replicates for each treatment. For the parameters evaluated daily, we used the split plot design, in which the different silages were assigned to the plots and the time of exposure to air was assigned to the subplots. There was no difference of additives on silage pH in any of the evaluation days. The control silage reached higher temperatures indicating greater vulnerability. All additives had no aerobic instability. Silages made with the use of microbial additives were effective in maintaining the aerobic stability.Keywords: aerobiosis, silage, fermentation, nutritional quality.Estabilidade aerobica em silagem de milho (Zea mays L.) ensilada com diferentes aditivos microbianos RESUMO. O objetivo deste trabalho foi avaliar diferentes aditivos microbianos, no tocante a eficiência da estabilidade aeróbia em silagens de milho. O híbrido de milho utilizado para cultivo e posterior confecção das silagens foi o DKB 310. Os tratamentos impostos às silagens foram: 1) Tratamento Controle, sem nenhum aditivo microbiano. 2) Tratamento com LPPA composto por: Lactobacillus plantarum CCT 0580 3,1x10 10