Ionophores have been widely used in the beef and dairy industry for decades to improve feed efficiency and performance by altering ruminal fermentation dynamics, increasing the level of propionate. Ionophores can also reduce ruminal proteolysis and ammonia synthesis, thus increasing the influx of protein into the small intestine in cattle, leading to improvements in performance and efficiency responses. Ionophores indirectly impact ruminal methanogenesis by decreasing the substrate used to produce methane. Despite the consistent benefits of using ionophores in cattle nutrition, their utilization is under public scrutiny due to concerns related to microbial adaptation. However, there is inconsistent evidence supporting these concerns, whereas ionophores are still an important dietary tool to enhance productivity and profitability in beef production systems.

-Twenty primiparous and multiparous Alpine breed goats at approximately 80 days of lactation were used in this experiment. The animals were housed individually in metal cages and distributed according to milk production in five 4 × 4 Latin squares. The experimental diets used in the experiment presented concentrate:forage ratio of 65:35. The treatments were characterized by increasing levels of 0, 33, 67 and 100% of high moisture corn silage (HMCS) replacing corn dry grain (CDG). Average intake of DM (1.62 kg/day, 3.90 % BW), CP (0.22 kg/day), NFC (0.76 kg/day) and TDN (1.29 kg/day) were not influenced by levels of HMCS. However, intake of NDF (0.53 kg/day) was significant for the different level of HMCS. Daily milk production and production of milk correct at 3.5% of fat, feed efficiency (MP/DMI), fat percentage, protein, lactose, total solids and milk urea nitrogen, with means of 1.86; 1.69; 1.11; 2.96; 2.85; 4.36; 10.96 and 17.1, respectively, were not influenced by the levels of HMCS. Percentage of non fat solids (8.00%) was affected by replacing levels of HMCS. The use of high moisture corn silage in the diet does not change milk production and it can be applied in total or partial substitution to dry corn grain in the feeding of milk goats.Key Words: dairy goats, dry matter intake, processed corn Utilização da silagem de grãos úmidos de milho em substituição ao milho seco no consumo, digestibilidade aparente, produção e composição do leite de cabras leiteiras RESUMO -Foram utilizadas 20 cabras da raça Alpina, primíparas e multíparas, com aproximadamente 80 dias em lactação, alojadas individualmente em gaiolas metálicas e distribuídas, de acordo com a produção de leite, em cinco quadrados latinos 4 × 4. As dietas experimentais utilizadas apresentaram relação concentrado:volumoso 65:35. Os tratamentos foram caracterizados por níveis crescentes 0, 33, 67 e 100% de silagem de grãos úmidos de milho (SGUM) em substituição ao grão seco de milho (GSM). As médias de consumo de MS (1,62 kg/dia, 3,90 %PV), proteína bruta (0,22 kg/dia), carboidratos não fibrosos (0,76 kg/dia) e nutrientes digestíveis totais (1,29 kg/dia) não foram influenciadas pelos níveis de SGUM. Entretanto, o consumo de FDN (0,53 kg/dia) foi significativo para os diferentes níveis de SGUM. A produção diária de leite e produção de leite corrigida a 3,5% de gordura (kg/dia), eficiência alimentar (PL/CMS), porcentagens de gordura, proteína, lactose, sólidos totais e nitrogênio ureico do leite, com médias de 1,86; 1,69; 1,11; 2,96; 2,85; 4,36; 10,96 e 17,1, respectivamente, não foram influenciados pelos níveis de SGUM. A porcentagem de extrato seco desengordurado (8.00%) foi afetada pelos níveis de substituição da SGUM. A utilização de silagem de grãos úmidos de milho na dieta não altera a produção de leite e pode aplicada em substituição parcial ou total ao grão seco de milho na alimentação de cabras leiteiras.Palavras-chave: cabras leiteiras, consumo de matéria seca, milho processado Revista Brasileira de Zootecnia

A minha mãe, Maria Dalva Jesus de Oliveira Marques, que me mostrou o caminho correto da vida, com muita garra e exemplo para enfrentar os desafios impostos sem medir força para ser mãe e pai simultaneamente.As minhas irmãs, Juliana e Joyce e ao meu amigo e ao mesmo tempo pai da vida, Durval Oliveira, que não negaram esforços para que eu completasse mais essa etapa na minha vida. DedicoAo meu pai, Gutemberg Marques "in memorian", pelos ensinamentos que até hoje são presentes na minha vida e me tornaram forte para enfrentar qualquer dificuldade apresentada na vida.Aos meus pais que adquiri durante essa etapa e que sempre serão especiais para mim, Valter e Adair Ruocco. E em especial a minha pequena, Daniele Ruocco, pelo amor, carinho, companheirismo, dedicação e muita paciência que sempre demonstrou e me tornou um homem muito melhor Aos estagiários que hoje são companheiros de pós graduação, Carol Guerra e Alvaro Bispo, pela ajuda nos experimentos.

Poor maternal nutrition can cause several maladaptive phenotypes in exposed offspring. While non-sex-specific and female-specific adaptations are well-documented, male-specific outcomes are still poorly understood. Of particular interest are the outcomes in bulls and rams, as developmental programming directly impacts long-term productivity of the animal as well as human food security. The following review discusses the impact of poor maternal dietary energy and protein on bull and ram developmental programming as it relates to growth, development, and reproductive capacity. The review also highlights the importance of the timing of maternal dietary insult, as early-, mid-, and late-gestational insults can all have varying effects on offspring.

Nutritional management during gestation is critical to optimize the efficiency and profitability of beef production systems. Given the essentiality of trace minerals to fetal developmental processes, their supplementation represents one approach to optimize offspring productivity. Our research group investigated the impacts of supplementing gestating beef cows with organic-complexed (AAC) or inorganic sources (INR) of Co, Cu, Mn, or Zn on productive and health responses of the progeny. Calves born to AAC supplemented cows had reduced incidence of bovine respiratory disease and were >20 kg heavier from weaning until slaughter compared to unsupplemented cohorts. Complementing these findings, heifer progeny born to AAC supplemented cows had accelerated puberty attainment. Collectively, research demonstrates supplementing trace minerals to gestating beef cows may be a strategy to enhance offspring productivity in beef production systems.

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Rendimentos de cortes, proporção tecidual da carcaça e composição centesimal da carne de caprinos jovens em função do grupo racial e do peso corporal de abate [Cut yields, carcass

-The objective of this work was to analyze the interrelations among weights and carcass measures of the longissimus lumborum muscle thickness and area, and of sternum tissue thickness, measured directly on carcass and by ultrasound scan. Measures were taken on live animals and after slaughter to develop models of multiple linear regression, to estimate the composition of shoulder blade, from selected variables in 89 kids of both genders and five breed groups, raised in feedlot system. The variables considered relevant and not redundant on the information they carry, for the common factor analysis, were used in the carcass composition estimate development models. The presuppositions of linear regression models relative to residues were evaluated, the estimated residues were subjected to analysis of variance and the means were compared by the Student t test. Based in these results, the group of 32 initial variables could be reduced to four variables: hot carcass weight, rump perimeter, leg length and tissue height at the fourth sternum bone. The analysis of common factors was shown as an effective technique to study the interrelations among the independent variables. The measures of carcass dimension, alone, did not add any information to hot carcass weight. The carcass muscle weight can be estimated with high precision from simple models, without the need for information related to gender and breed, and they could be built based on carcass weight, which makes it easy to be applied. The fat and bones estimate models were not as accurate.