ABSTRACT This research was conducted to investigate the effect of live and inactive sugarcane yeast on beef cattle voluntary intake, apparent digestibility of nutrients, ruminal pH, volatile fatty acids (VFA) concentrations, and ruminal ammonia. Five rumen-cannulated Nellore heifers were distributed in a 5×5 Latin square design, with five experimental periods of 15 days, with seven days for adaptation to the additives and the remaining days for data records and sampling. Total mixed ration (TMR) was composed by corn silage (20%) and concentrate (80%) based on corn and soybean meal. Five treatments were evaluated: without additive use (negative control; NC); chemical buffer addition – 0.71% in concentrate DM of sodium bicarbonate and 0.18% of magnesium oxide (positive control, PC); 10 g/day live yeast (LY); 15 g/day of inactive yeast (IY15); and 30 g/day of inactive yeast (IY30). Sugarcane yeasts were directly infused in rumen immediately after morning and afternoon feed supply. Feed additives did not affect voluntary intake, nutrient digestibility, and sorting behavior of animals. However, heifers from all treatments presented preferential intake of fibrous fraction of diet, especially those from NC and IY15. Nitrogen balance, VFA concentrations, and blood parameters were not influenced as well. Sodium bicarbonate and magnesium oxide led to greater ruminal pH than yeast, and IY15 presented greater pH than IY30. Ruminal ammonia was increased by the use of additives. Active and inactive yeasts are not recommended as feed additives for bovines fed diets with 80% of concentrate since it allows animals to select fibrous particles from TMR, and no representative gain in ruminal parameters and digestibilities are guaranteed.

RESUMO. O objetivo deste trabalho foi avaliar a suplementação de vacas em pastagens de Brachiaria decumbens durante a transição águas-seca. Foram utilizadas oito vacas 1/2 Holandês/Zebu (497 ± 50 kg), distribuídas em dois quadrados latinos 4 x 4, sendo os tratamentos em fatorial 2 x 2 (100% de sal mineral versus sal nitrogenado contendo 25:25:50% de ureia:fubá e sal mineral; e 1,5 versus 3,0 kg d-1 de concentrado por vaca). O experimento teve duração de 56 dias, divididos em quatro períodos de 14 dias, sendo os sete últimos dias para coleta de dados. Não foi encontrado efeito de interação (p > 0,05) entre o suplemento e os diferentes níveis de concentrado para nenhuma das variáveis avaliadas. Não foi observado efeito (p > 0,05) de suplemento nem de nível de concentrado sobre as excreções urinárias dos derivados de purina, compostos nitrogenados microbianos e eficiência microbiana. O sal nitrogenado aumentou (p < 0,05) o consumo de nitrogênio e aumentou a excreção urinária de nitrogênio, levando à redução do balanço de nitrogênio, enquanto o maior nível de concentrado aumentou (p < 0,05) o consumo de nitrogênio e o total de nitrogênio excretado no leite. Recomenda-se, portanto, para vacas mestiças no período de transição águas-seca, o uso de 1,5 kg d-1 de concentrado fornecido durante as ordenhas, com uso somente de sal mineral em vez de sal nitrogenado à vontade na pastagem.

ABSTRACT. The objective this work was to evaluate the supplementation of cows on Brachiaria decumbens pasture during the rainy-dry transition. Eight 1/2 Holstein/Zebu cows (497 ± 50 kg) were distributed in two 4 x 4 Latin squares, with 2 x 2 factorial treatments (100% mineral salt versus nitrogen salt containing 25:25:50% urea: corn: mineral salt, and 1.5 versus 3.0 kg d-1 concentrate per cow). The experiment lasted 56 days, divided into four periods of 14 days, the last seven days for data collection. No interaction effect (p > 0.05) was detected between the supplement and the different levels of concentrate for any of the evaluated variables. No effect (p > 0.05) of supplement or concentrate level was observed on urinary excretions of purine derivatives, microbial nitrogen compounds and microbial efficiency. Nitrogen salt increased (p < 0.05) nitrogen intake and increased urinary nitrogen excretion, leading to a reduced nitrogen balance, while the higher concentrate level increased (p < 0.05) nitrogen intake and the total amount of nitrogen excreted in milk. Therefore, it is recommended, for crossbred cows in the rainy-dry transition period, the supply of 1.5 kg d-1 concentrate during milking, using only mineral salt instead of nitrogen salt at will on pasture.

ABSTRACT This study analyzed seasonal variations in the testes, the concentration of sex hormones, the parameters of fresh and thawed semen, and the sexual behavior of male Alpine goats from a temperate region in a tropical climate and possible interference with fertility. The maximum and minimum temperature and luminosity were recorded daily, while seminal, hormonal, and behavioral assessments were carried out every fortnight. The maximum and minimum temperature (°C) and luminosity (h) were recorded daily always at 17.00 h. The scrotal circumference (cm), testicular volume (mL), volume (mL), appearance (creamy, milky, aqueous) and coloration (white, white-yellowish, and yellowish) seminal, turbulence or mass movement (0 to 5), progressive spermatic motility (0 to 100%), spermatic force (0 to 5), concentration (spermatozoids/mL), spermatic pathologies, hypoosmotic test (%), serum levels of FSH (mUI/mL), LH (mUI/mL), testosterone (ng/mL), and sexual behaviors were carried out every fortnight. There was a difference between the scrotal circumference evaluated monthly, testicular volume, volume and concentration of fresh semen, sperm vigor of the thawed semen, serum levels of testosterone, FSH and LH, and some sexual behaviors. Thus, the changes that occur in the quantity and quality of sperm, in the hormonal profile, and in sexual behaviors should not be regarded as an impediment to the use of male Alpine goats in tropical climates throughout the year. These variations do not lead to changes in the semen that may compromise the fertility of these animals.

RESUMO Objetivou-se com este trabalho avaliar o desenvolvimento e a qualidade da cana-de- açúcar variedade RB 867515 e os atributos químicos do solo em resposta à aplicação de níveis variáveis de fertilização. Utilizou-se o delineamento experimental em blocos casualizados, com cinco tratamentos (0, 3, 6, 9 e 12t/ha de cama de frango) e quatro repetições. Aos quatro meses pós-plantio não houveram diferenças entre os níveis de cama de frango sobre a altura das plantas, diâmetro do colmo, largura da folha e comprimento da folha, mas o número de plantas/m linear e número de folhas/planta atingiram valores máximos utilizando 8,7 e 5,3 t/ha de cama de frango, respectivamente. Aos 12 meses após o plantio foram observados aumentos de P, K, Ca e Mg pelo incremento no nível de fertilização com cama de frango e aumento linear na produtividade de massa verde da cana. Portanto, pode-se aplicar até 12 t/ha de cama de frango para maximizar o desempenho da cultura e melhorar a fertilidade do solo. Além da produtividade alcançada, o acúmulo de açúcar solúvel (média de 20 graus Brix), bem como os teores de matéria seca (32,9%) e fibra em detergente neutro (46,7%) indicam que a cana variedade RB 867515, de ciclo médio/tardio, já se apresenta apropriada para o primeiro corte para alimentação animal aos 12 meses pós-plantio.

SUMMARY The aim of this work was to evaluate the development and quality of sugarcane variety RB 867515 and chemical attributes of the soil in response to the application of increasing level of fertilization. It was used randomized blocks design, with five treatments (0, 3, 6, 9 and 12 t/ha of poultry litter) and four replications. At four months after planting there were no differences among poultry liter levels on plant height, culm diameter, and leaves width and length, but the number of plants/m linear and number of leaves/plant reached maximum values using 8.7 and 5.3 t/ha of poultry litter, respectively. At 12 months after planting, there was increase in P, K, Ca and Mg by increasing the level of fertilization with poultry litter and linear increase in productivity of sugarcane green mass. Therefore, up to 12 t/ha of poultry litter can be applied to maximize the performance of sugarcane and improve soil fertility. In addition to the reached productivity, the accumulation of soluble sugar (mean 20 degrees Brix), as well as contents of dry matter (32.9%) and neutral detergent fiber (46.7%) indicates that the sugarcane variety RB 867515, of mean/late cycle, presents appropriate for the first cut for animal feeding at 12 months after planting.

RESUMO. O objetivo desse estudo foi avaliar a inclusão de gordura protegida e de diferentes níveis de PB, na dieta para vacas mestiças, no início da lactação. Foram utilizadas 12 vacas, distribuídas em quadrados latinos 4 x 4 e quatro tratamentos (12 ou 16% de PB, com ou sem MEGALAC-E(r)). Análises estatísticas foram realizadas utilizando Anova e correlações lineares de Pearson. A gordura protegida não influenciou o consumo de MS e MO (p > 0,05). O aumento de PB elevou o consumo de PB e EE e diminuiu o de carboidratos não fibrosos (CNF; P<0,05). A gordura protegida aumentou (p < 0,05) a digestibilidade da MS, MO, PB e cinzas no menor teor de proteína. O aumento de PB elevou os níveis de ureia sanguínea e urinária (p < 0,05). Não houve diferença (p > 0,05) na produção e composição do leite em função da gordura protegida ou do teor de PB. A inclusão de gordura protegida e o maior teor de PB (16%) na dieta não resultaram em benefícios na produção e composição do leite de vacas mestiças, portanto recomenda-se utilizar dietas contendo 12% de PB, sem a inclusão de gordura protegida.

ABSTRACT. Current study evaluated the inclusion of protected fat and different levels of crude protein (CP) in the diet of crossbreed cows in early lactation. Twelve cows were distributed in a 4 x 4 factorial design, with four treatments (12 or 16% CP, with or without MEGALAC-E(r)). Statistical analyzes with ANOVA and Pearson's linear correlation procedures were performed. Protected fat did not affect intake of dry matter (DM) and organic matter (OM) (p > 0.05). Increased CP raised consumption of CP and EE and decreased the non-fiber carbohydrates (NFC; p <0.05). Protected fat increased (p <0.05) the digestibility of DM, OM, CP and ashes in the lower protein content. CP increase raised the level of blood and urinary urea (p < 0.05). There was no difference (p > 0.05) on milk yield and composition due to protected fat or CP rates. Since the inclusion of protected fat and higher content of CP (16%) in the diet did not benefit the production and composition of milk in crossbreed cows, diets with 12% CP without the inclusion of protected fat are recommended.

ABSTRACT The objective of this study was to evaluate the effect of different sources of lipids in the diets of dairy cows on the intake and digestibility of nutritional fractions, and milk production and composition. The experiment was conducted in a 42-hectare area divided into eight paddocks covered with Brachiaria brizantha. Twelve crossbred Holstein × Zebu cows were distributed into three simultaneous 4 × 4 Latin squares. The treatments consisted of different sources of lipids, as follows: diet with no extra source of lipids; diet with cottonseed as the source of lipids; diet with soy oil; and diet with used frying soy oil. The intakes of dry matter, neutral detergent fiber, crude protein, total carbohydrates, and non-fibrous carbohydrates were similar for all diets. The use of lipid sources caused a decrease in the apparent digestibility of dry matter, neutral detergent fiber, non-fibrous carbohydrates, and crude protein. The levels of protein, lactose, and defatted dry matter were reduced with the use of lipid sources but did not affect milk production. The use of cottonseed, soy oil, and used frying soy oil as sources of lipids in diets for lactating cows at pasture do not improve milk production, and their use is therefore optional.

Estudou-se o efeito da inclusão de 0; 5; 10 e 15% de bagaço de mandioca, com base na matéria seca da dieta total de vacas mestiças Holandesas vs. Zebu, sobre a produção e composição do leite e sobre os impactos no custo da alimentação. Os animais estavam no terço médio de lactação e pesavam em média 478,5 kg. A dieta com 15% de bagaço de mandioca acrescentou 13,2% à produção, comparada à dieta controle. A conversão alimentar apresentou efeito quadrático com ponto mínimo em 4,2% de inclusão de bagaço de mandioca. A proteína bruta, único componente do leite que sofreu alteração, aumentou linearmente com os níveis de inclusão de bagaço de mandioca. O tratamento com 15% de bagaço de mandioca representou maior custo operacional efetivo (42,8% mais elevado em relação ao tratamento controle) e o maior ponto de nivelamento para a produção e preço do leite. Observaram-se os menores pontos de nivelamento para os tratamentos com 5 e 10% de inclusão de bagaço de mandioca, os quais apresentaram melhores resultados econômicos. O concentrado foi o principal responsável pela elevação dos custos, particularmente, quando ocorre a redução da razão volumoso : concentrado em função dos maiores teores de inclusão de bagaço de mandioca.

The addition of 0; 5; 10 and 15% cassava bagasse, based on the dry matter of the total diet of crossbred Holstein v. Zebu cows, was evaluated on milk production and composition and on the impacts of diet costs. The animals, weighing an average of 478.5 kg, were in the middle third lactation period. Diet with 15% cassava bagasse provided a 13.2% increase in production when compared to control. Feed conversion had a quadratic effect with minimum point at 4.2% of cassava bagasse inclusion. Crude protein, the only milk component that changed, increased linearly with the inclusion of cassava bagasse levels. Treatment with 15% cassava bagasse caused a more effective operational cost (42.8% higher when compared to control) and the highest leveling point for milk production and price. The lowest leveling points were treatments with 5 and 10% inclusion of cassava bagasse, which had the best economic results. Concentrates caused cost increase, particularly when roughage : concentrate ratio decreased due to higher cassava bagasse inclusion levels.

Esse estudo teve como objetivo avaliar o uso de suplementos, com diferentes proporções de ureia e sal mineral, na alimentação de vacas mestiças leiteiras. Foram utilizados dez animais, com peso corporal médio de 480 kg ± 9,7, distribuídas em dois quadrados latinos 5 x 5, com tratamentos de suplementos com diferentes porcentagens de ureia e sal mineral, sendo: 10:10; 10:20; 20:10, 20:20 e 0:100, completados para 100% com fubá de milho. Os dados foram analisados utilizando-se o programa SAS, adotando-se um nível de significância de 0,05. O uso de suplemento aumentou (p < 0,05) o consumo de matéria seca (MS) total da dieta. O aumento do teor de ureia no suplemento diminuiu o consumo de MS de suplemento. O uso de suplemento aumentou (p < 0,05) a digestibilidade da MS. Os tratamentos com presença de suplemento proporcionaram maior (p < 0,05) produção de leite. Os suplementos podem ser usados para corrigir deficiências nutricionais, resultando em maior consumo, digestibilidade e produção de leite. Os suplementos com 20% de ureia em sua composição resultaram em menor consumo com mesmo desempenho dos animais, podendo-se concluir que esses tratamentos apresentaram melhor eficiência de utilização.

This study aimed to evaluate the use of supplementary feed with different percentages of urea and mineral salt for crossbred milk cows. Ten animals were used, mean body weight 480 kg ± 9,7, distributed in a 5 x 5 double Latin square, with treatments of supplements with different urea and mineral salt percentages, namely, 10:10; 10:20; 20:10 and 20:20, completed to 100% with corn meal. Data underwent statistical analysis by SAS at 0.05 significance level. The use of supplements increased (p < 0.05) the total dry matter (DM) intake of diet. The increase in the level of urea in the supplement decreased DM intake of supplement. The use of supplements increased (p < 0.05) DM digestibility. The treatments with presence of supplement showed higher (p < 0.05) milk production. Supplemented diets may be used to correct nutritional deficiencies of sugar cane, with higher intake, digestibility and milk production. Treatments with 20% urea in the composition of the supplement caused a lower DM consumption with the same performance in the animals. The above-mentioned treatments had the best efficiency.

Objetivou-se determinar as frações que compõem os carboidratos e as proteínas, bem como as características fermentativas da silagem de capim-elefante, sem e com emurchecimento, e acrescida de farelo de mandioca. Foi adotado o esquema fatorial 4 x 2, com quatro repetições no delineamento inteiramente casualizado. Os fatores avaliados foram níveis de farelo de mandioca (0; 7,5; 15 e 22,5% MN) e emurchecimento (sem e com). Foram usados silos de PVC, com 50 cm de altura e 10cm de diâmetro para a produção das silagens. As frações de CHO (A+B1 e B2) e as frações nitrogenadas B3 e C foram influenciadas pela associação do emurchecimento aos níveis de farelo de mandioca, o que não ocorreu com as frações nitrogenadas (A e B1+B2) das silagens. A adição de farelo de mandioca reduziu linearmente a fração C dos carboidratos. No que concerne às características fermentativas das silagens, o pH apresentou comportamento quadrático. O nitrogênio amoniacal apresentou comportamento quadrático e linear decrescente para as silagens sem e com emurchecimento, respectivamente. A utilização do farelo de mandioca reduz a fração B2 e a porção de carboidratos indisponíveis. As principais frações proteicas das silagens estudadas são as frações A e B1+B2. O emurchecimento e a adição de farelo de mandioca melhoram o valor nutritivo e as características fermentativas das silagens estudadas.

The objective of this work was to determine the fractions that compose the carbohydrates (CHO) and proteins and fermentative characteristics of elephant grass silage without or with wilting and added of cassava meal. The 4 x 2 factorial scheme was adopted, with four repetitions, in a completely randomized design. The factors evaluated were wilting (without and with) and cassava meal levels (0; 7.5; 15 and 22.5 % DN). PVC silos with 50cm height and 10cm diameter were used for silages production. A+B1 and B2 CHO fractions and B3 and C nitrogen fractions of silages were influenced by association of wilting with cassava meal levels, the wilting and the cassava meal inclusion had no effect on A and B1+B2 nitrogen fractions. The cassava meal addiction linearly reduced the CHO C fraction. Relative to variables inherent to silages' fermentative characteristics, pH presented quadratic behavior. Ammonia nitrogen, presented quadratic and decreasing linear behavior for silages without and with wilting, respectively. The use of cassava meal reduces the B2 and unavailable carbohydrates fraction. The main protein fractions of the silages studied are A and B1 + B2 fractions. Wilting and the addition of cassava meal improved the nutritive value and fermentation characteristics of the silages studied.

The objective was to assess the effects of a concentrate consisting of two types of corn: flint and dent, with three different grinding degrees (1, 3 and 5 mm), as a function of intake, performance and digestibility of three crossbred dairy suckling heifers. A randomized block design involving 54 crossbred heifers in a 2 × 3 factorial arrangement was used to assess intake and performance patterns. In order to assess digestibility, the experimental design was completely randomized, consisting of 24 crossbred heifers. Weighting and measurements of height at withers and thoracic perimeter were performed. There was no significant interaction between grinding degree and corn type for any of the studied variables. The daily intake of concentrate dry matter was higher for flint corn (243 g/day) as compared with dent corn (160 g/day). The grinding degree caused difference in the dry matter, crude protein and ether extract intake, with higher intake when 3 and 5 mm sieves were used in the process. There was no difference regarding average daily gain and increased withers, croup and thoracic perimeter. Likewise, feed conversion did not differ. Regarding dry matter digestibility, there was an effect resulting from the hardness of corn (78.9% for dent, and 84.3% and for flint corn). As for the grinding degree, the highest value of dry matter digestibility was found when using 5 mm sieves (84.2%), whereas the percentage values found for 1 mm and 3 mm mesh sieves were 79.1% and 78.1%, respectively. It is recommended that heifer calves in the early stage of growth be fed flint corn ground through 3 or 5 mm mesh sieves.

The objective of the experiment was to classify 20 protein co-products and by-products of the biodiesel industry with potential to use in ruminant feeding. The meals evaluated were: cottonseed, canudo-de-pito, crambe, sunflower, castor-oil seeds detoxified with calcium, non-detoxified castor-oil seeds and soybean; and the cakes were: cottonseed, peanut, babassu, crambe, palm oil, sunflower, licuri, macauba seeds, non-detoxified castor-oil seeds, turnip and jatropha. The samples were quantified to determine dry matter (DM), organic matter (OM), crude protein (CP), ether extract (EE), neutral detergent fiber corrected for ash and protein (NDFap), non-fiber carbohydrates (NFC), acid detergent fiber corrected for ash and protein (ADFap), lignin, cutin and starch levels. The CP profile was characterized in fractions A, B1, B2, B3 and C. The in vitro dry matter digestibility (IVDMD), in vitro neutral detergent fiber digestibility (IVNDFD), rumen degradable and undegradable protein, intestinal digestibility, indigestible neutral detergent fiber and undegradable neutral detergent insoluble protein were evaluated. The OM, CP, EE, NDFap, NFC, ADFap, lignin, cutin and starch contents varied from 81.95 to 95.41%, 18.92 to 57.75%, 0.56 to 18.40%, 10.13 to 62.30%, 3.89 to 27.88%, 6.15 to 36.86%, 1.19 to 5.04%, 0 to 17.87% and 0.68 to 14.50%, respectively. The values of fractions A, B1, B2, B3 and C ranged from 5.40 to 43.31%, 0.08 to 37.63%, 16.75 to 79.39%, 1.86 to 59.15% and 0.60 to 11.47%, respectively. Concentrations of IVDMD, IVNDFD, rumen-degradable and undegradable protein, intestinal digestibility, indigestible NDF and undegradable neutral detergent insoluble protein ranged from 31.00 to 95.92%, 55.04 to 97.74%, 41.06 to 97.61%, 2.39 to 58.94, 9.27 to 94.26%, 1.05 to 40.80% and 0.29 to 2.92%, respectively. Some of these products can replace soybean meal, specially the Macauba seeds cake, cottonseed meal and peanut and turnip cakes based on digestive characteristics.

Objetivou-se avaliar o comportamento ingestivo de novilhas leiteiras alimentadas com níveis de farelo de cacau (0; 7; 14 e 21%). Foram utilizadas 20 novilhas leiteiras ¾ Gir x ¼ Holandês, com peso corporal inicial médio de 165,5 ± 35,8kg. Os animais foram distribuídos em delineamento inteiramente casualizado, com quatro tratamentos e cinco repetições, e receberam dietas compostas de silagem de capim elefante como volumoso e concentrado com níveis crescentes de inclusão de farelo de cacau. Foram avaliados os consumos, assim como suas eficiências de alimentação e ruminação. Para determinação do comportamento ingestivo, as novilhas foram submetidas, no penúltimo dia do período experimental, à observação visual, a cada cinco minutos, durante 24 horas. Os consumos de matéria seca, de fibra em detergente neutro, de carboidratos não fibrosos e de nutrientes digestíveis totais não foram influenciados pelos níveis de inclusão de farelo de cacau na dieta. Os tempos gastos em alimentação, ruminação e ócio não diferiram entre os tratamentos, assim como o número de períodos e os tempos gastos em cada período das respectivas atividades. O tempo gasto por bolo ruminado, o número de mastigações por bolo, o número de bolos ruminados por dia e o tempo de mastigação total não sofreram efeito das dietas. A eficiência de alimentação dos carboidratos não fibrosos teve efeito linear crescente, à medida que foi incluso o farelo de cacau na dieta. A inclusão de até 21% de farelo de cacau na dieta total não altera o comportamento ingestivo de novilhas leiteiras.

The objective was to evaluate the ingestive behavior of dairy heifers fed different cocoa meal levels. Twenty ¾ Gir x ¼ Holstein dairy heifers, with 165.5 ± 35.8kg of body weight, were used. The animals were distributed in a completely randomized design, with four treatments and five repetitions, receiving diets composed by elephant grass silage as the roughage and concentrate with increasing levels of cocoa meal. The intakes were evaluated, and also their feeding and rumination efficiencies. To determine the ingestive behavior, the heifers were submitted, in the last day of the experimental period, to visual observation, at each five minutes, during 24 hours. The dry matter, neutral detergent fiber, non-fiber carbohydrates and total digestible nutrients intakes were not influenced by cocoa meal inclusion levels in the diet. The time spent feeding, ruminating and in idle did not differ among treatments, neither did the number of periods and the time spent in each period with the respective activities. The time per ruminated bolus, chewing number per bolus, number of ruminated bolus per day and total chewing time were not affected by the diets. The non-fiber carbohydrates feeding efficiency had increasing linear effect as cocoa meal was included in the diet. The inclusion of up to 21% of cocoa meal in the total diet did not alter negatively the ingestive behavior of dairy heifers.

Foram estudados os efeitos da adição de 0,0; 0,75; 1,5 e 2,25% de óxido de cálcio no bagaço de cana-de-açúcar (com base na matéria natural) com o objetivo de avaliar o desempenho, o consumo de nutrientes e a digestibilidade aparente das dietas e dos nutrientes em ovinos mestiços da raça Santa Inês e raças nativas. Vinte e quatro ovinos, mantidos em total confinamento, foram distribuídos em delineamento inteiramente ao acaso, com quatro níveis de óxido de cálcio e seis repetições. Os animais foram mantidos em baias individuais, por 77 dias. Os primeiros 14 dias foram de adaptação e, então, seguiram-se três períodos de 21 dias de coleta de dados. Na determinação da digestibilidade, utilizou-se o método de coleta total de fezes, que foi realizada nos quatro últimos dias do período experimental. As fezes foram coletadas três vezes ao dia, às 7, 13 e 18 h. O uso do óxido de cálcio não influenciou os consumos de matéria seca, proteína bruta, fibra em detergente neutro, fibra em detergente ácido e nutrientes digestíveis totais, mas houve efeito linear sobre ganho de peso, com o aumento nas doses de óxido de cálcio, mas não sobre a conversão alimentar e os coeficientes de digestibilidade aparente da matéria seca, proteína bruta e fibra em detergente ácido. Entretanto, foi observado efeito quadrático para o coeficiente de digestibilidade aparente da fibra em detergente. A utilização do bagaço de cana hidrolisado com óxido de cálcio em níveis a partir de 1,5% da matéria natural promove melhoras no desempenho de ovinos e aumenta a digestibilidade apenas da fibra em detergente neutro.

The addition effects of 0.0; 0.75; 1.5 and 2.25% of calcium oxide on sugar-cane bagasse (on natural matter basis) were studied to evaluate the performance, nutrients intake and apparent digestibility of the diets and nutrients in crossbred sheep of Santa Inês and native breeds. Twenty-four sheep, maintened in total confinement, were assigned in a completely randomized experimental design, with four levels of calcium oxide and six repetitions. Animals were kept in individual pens for 77 days. The first 14 days were for animals adaptation and three periods of 21 days of data collection. The method of total fecal collection was used to estimate digestibility, which was carried in four days at the end of the experimental period. Feces were collected three times a day, at 7 am, 1 and 6 pm. The intake of dry matter, crude protein, neutral detergent fiber, acid detergent fiber and total digestible nutrients were not influenced by the use of calcium oxide. There was a linear effect in daily weight gain with increasing calcium oxide dose. However, there was no treatment effect on feed conversion and apparent digestibility coefficients of dry matter, crude protein and acid detergent fiber. Whereas the quadratic effect was observed for neutral detergent fiber apparent digestibility coefficient. The use of the hydrolized sugar cane bagasse with calcium oxide, from 1.5%, promote increase in performance of sheep and increase digestibility in neutral detergent fiber.

Dezesseis vacas mestiças Holandês × Zebu (grau de sangue variando de ½ a ¾ Holandês × Zebu) foram distribuídas segundo quatro quadrados latinos 4 × 4 para se avaliar a viabilidade econômica do aumento do nível de concentrado na dieta. As vacas de terceira ou quarta lactação, com produção anterior entre 2.500 e 3.000 kg, ajustada para 300 dias, foram manejados a pasto na época das águas, e com 110 dias de lactação no início do período experimental. Com os preços do leite e concentrado praticados no momento do estudo, não é interessante a utilização de concentrado na dieta de vacas leiteiras alimentadas com cana-de-açúcar. Contudo, considerando os aspectos produtivo e econômico conjuntamente, e os preços de R$ 0,70 e R$ 0,50 para o leite e o concentrado, respectivamente, a utilização de 24% de concentrado na dieta é a opção mais interessante para vacas leiteiras alimentadas com cana-de-açúcar.

Sixteen crossbred Holstein × Zebu cows (groups from ½ to ¾ of Holstein × Zebu) at third of fourth lactation were allotted to four 4 × 4 Latin squares to evaluate the economical viability of increasing dietary concentrate level. Cows presented previous milk yield from 2,500 to 3,000 kg, adjusted for 300 days, and grazed pasture during the rainy season, and with 110 days of laction in the beginning of the experimental period. Because of the prices of milk and concentrate during the experiment, it is not interesting to use concentrate in the diets of milk cows fed sugar cane. If the productive and economical aspects toghther and the prices of R$ 0.70 and R$ 0.50 for the milk and the concentrate, respectively are considered, the use of 24% concentrate in the diet is the most interesting option for dairy cows fed sugar cane.

O experimento foi conduzido para avaliar as perdas por gases e efluente, as características fermentativas e o valor nutritivo de silagens de capim-elefante contendo como aditivos farelo de mandioca, casca de café ou farelo de cacau. Utilizou-se delineamento inteiramente casualizado, em esquema fatorial 3 x 4, com três aditivos avaliados em quatro níveis (0, 10, 20 e 30% da matéria natural), cada um com cinco repetições. O material foi acondicionado em silos de PVC por 60 dias. Após abertura dos silos, foram realizadas pesagens para determinação das perdas, pela quantificação da produção de efluente e das perdas por gases. Amostras foram coletadas para posteriores análises de nitrogênio amoniacal e pH e da composição químico-bromatológica. A adição dos aditivos provocou aumento dos teores de matéria seca, e farelo de mandioca foi o aditivo mais eficiente no controle das perdas por efluente e gases. A adição de farelo de mandioca, casca de café e farelo de cacau garantiu altas taxas de recuperação de MS, enquanto o farelo de mandioca e o farelo de cacau favoreceram a redução dos valores de pH e os teores de nitrogênio amoniacal, respectivamente, refletindo na melhoria do perfil de fermentação das silagens. As silagens contendo farelo de mandioca apresentaram maiores teores de nutrientes digestíveis totais e garantiram os menores teores de fibra em detergente neutro, fibra em detergente ácido, celulose e lignina. A adição de farelo de cacau ao capim-elefante no momento da ensilagem contribui para o aumento dos teores de nitrogênio total, porém aumenta os teores de nitrogênio insolúvel em detergente neutro e em detergente ácido.

The experiment was conducted to determine losses by gases and effluent, fermentation characteristics and nutritional value of elephant grass silage containing cassava meal, coffee hulls and cocoa meal. It was used a completely randomized experimental design in a 3 x 4 factorial scheme, with three additives evaluated in four levels (0, 10, 20 and 30% of natural matter), each one with five repetitions. The material was ensiled in PVC silos for 60 days. After opening of the silos, weightings were carried out for determination of losses through the quantification of effluent production and also by losses by gases. Samples were collected for subsequent analyses of ammonia nitrogen content and pH values, as well as the chemical-bromatological composition. The additive addition caused an increase in the dry matter contents and cocoa meal was the most efficient additive to control effluent and gas losses. The addition of cassava meal, coffee hulls and cocoa meal assured high recovery rates of dry matter, while cassava meal and cocoa meal favored the reduction of pH values and ammonia nitrogen contents, respectively, resulting in silages fermentation profile improvement. The silages containing cassava meal presented greater total digestible nutrients contents and they assured lower neutral detergent fiber, acid detergent fiber, cellulose and lignin contents. Addition of cocoa meal to elephant grass at the moment of the ensilage contributed to increase total nitrogen content, however it increases insoluble nitrogen contents in neutral detergent and acid detergent.