ABSTRACT Two studies were carried out to evaluate the effects of levels of soybean meal produced from damaged soybean grains replacing normal soybean meal on in vitro and in situ digestibility of ruminant diets as well as on intake, digestibility, and animal performance of growing/finishing lambs. In trial 1, we evaluated the in vitro digestibility of each soybean meals (normal and damaged), as well as diets containing levels of the damaged replacing the normal (0, 333, 667 and 1,000 g.kg−1) soybean meal on kinetic parameters of in vitro cumulative gas production, in vitro dry matter and crude protein digestibility, in situ rumen-degradable protein, rumen-undegradable protein, and in vitro intestinal digestibility of rumen-undegradable protein. In trial 2, we used 48 growing/finishing lambs to evaluate the effects of damaged soybean meal levels (0, 333, 667, and 1,000 g.kg−1) replacing normal soybean meal in feedlot diets (20:80 roughage:concentrate ratio) on intake and digestibility of nutrients and on animal performance. The damaged soybean meal presented lower values for total gas production and in vitro dry matter digestibility than normal soybean meal. Higher rumen-undegradable protein was estimated for damaged soybean meal than for the normal and consequently lower rumen-degradable protein for damaged compared to normal. Because of the lower rumen-degradable protein, damaged soybean meal promoted lower in vitro ammonium nitrogen (NH3-N) concentrations than the normal in feedlot diets. In the in vivo trial, there were no effects of damaged soybean meal levels in the diets on intake and digestibility of nutrients (dry matter, organic matter, crude protein, and fiber) as well as on total weight gain, average daily gain, carcass yield, or feeding efficiency. Thus, damaged soybean meal can fully replace the normal one in lamb feedlot diets (in up to of 1,000 g.kg−1 of the normal soybean meal) without causing adverse effects on intake and digestibility of nutrients and on animal performance.

ABSTRACT This study aimed to evaluate the frequency and intensity of GreenFeed (GF) use by Nellore steers using different attractants in pastures of integrated systems. The attractant protein supplement and Tifton bermudagrass pelleted hay flavored with vanilla were evaluated over a period of 15 days. The pelleted hay stimulated the animals to stay longer in the equipment (24.23 s), with 8% more visits in intervals longer than 30 s in contrast to protein supplement. This indicates that pelleted hay flavored with vanilla is a potential attractant to encourage Nellore steers to visit GF in grazing systems.

RESUMO O sorgo é uma cultura que se destaca como alternativa ao milho devido a menor exigência em fertilidade do solo e maior tolerância ao déficit hídrico. A falta de informações quanto ao comportamento qualitativo dificulta a recomendação de cultivares de sorgo de diferentes propósitos. Objetivou-se avaliar a composição bromatológica e a digestibilidade in vitro da silagem de cultivares de sorgo de diferentes propósitos, em duas épocas de cultivo. O delineamento experimental utilizado foi em blocos casualizados, com os tratamentos dispostos em esquema de parcela subdividida, com quatro repetições. Os tratamentos da parcela corresponderam a seis híbridos de sorgo de diferentes propósitos (BRS 308 e BRS 310, graníferos; BR 655 e BRS 610, forrageiros; BR 506 e CMSXS 647, sacarinos). Os tratamentos da subparcela corresponderam a duas épocas de cultivo (primeira safra e segunda safra). A cultivar de sorgo forrageiro BRS 655 apresentou maior teor de carboidratos não fibrosos e menor teor de fibra potencialmente digestível. As cultivares de sorgo sacarino obtiveram os maiores teores de carboidratos solúveis, os menores teores de fibra insolúvel em detergente neutro indigestível na segunda safra, e as maiores digestibilidades in vitro da matéria seca. As silagens de sorgo sacarino e de sorgo forrageiro BRS 655 apresentam maior valor nutritivo.

ABSTRACT Sorghum is a crop that stands out as an alternative to corn due to lower soil fertility demand and increased tolerance to drought. Lack of information about the qualitative behaviour of sorghum hinders the recommendation of different purpose sorghum cultivars. The goal was to evaluate the chemical composition and in vitro digestibility of different purpose sorghum cultivar silages, at two cropping seasons. The trial was conducted at the Plant Production Department, Federal Institute of Education, Science and Technology of Rondônia, Colorado do Oeste campus, and chemical analyses and in vitro incubation were performed at the Laboratory of Animal Nutrition, Federal University of Mato Grosso, Cuiabá campus. The experimental design was a randomized block with a split-plot arrangement and four replications. Plot treatments consisted of six different purpose sorghum cultivars (BRS 308 and BRS 310, grain sorghum; BR 655 and BRS 610, forage sorghum; and BRS 506 and CMSXS 647, sweet sorghum). Split-plot treatments consisted of two cropping periods (first crop and second crop). Forage sorghum cultivar BRS 655 demonstrated higher non-fiber carbohydrate content and lower potentially digestible fibre content than the other cultivars did. Sweet sorghum cultivars had higher levels of water soluble carbohydrates and non-protein nitrogen based on protein, lower indigestible neutral detergent fibre content at second crop, and higher in vitro dry matter digestibility than the other cultivars. The silages of sweet sorghum cultivars BRS 506 and CMSXS 647, and forage sorghum cultivar BRS 655 presented higher nutritional values.

RESUMO Objetivou-se com este trabalho avaliar o efeito da suplementação com diferentes fontes proteicas na dieta de vacas leiteiras mantidas em pastagem de Brachiaria brizantha MG5 sobre os níveis séricos de glicose, triglicerídeos, colesterol e ureia e das enzimas gama glutamina transferase, creatina quinase e aminotransferase. Avaliaram-se diferentes fontes proteicas: coproduto de feijão, farelo de soja, farelo de girassol e farelo de algodão. Foram utilizadas 8 vacas cruzadas 5/8 (Holandês x Gir), peso médio 500±60,33kg, produção média de leite de 14,85±3,28kg/dia, entre 60 e 90 dias de lactação, em delineamento quadrado latino 4 x 4 duplo e simultâneo. Cada período experimental teve duração de 15 dias, sendo 10 dias iniciais para adaptação dos animais e os demais para avaliação e coleta de dados. Houve efeito de interação (P<0,05) das fontes proteicas e tempos de coleta sobre os níveis séricos de glicose. Não houve efeito (P>0,05) das fontes proteicas para os valores de triglicerídeos, colesterol e ureia dos animais, com média de 6,46±2,05; 182,43±37,52 e 38,20±12,29mg/dL, respectivamente. Houve efeito (P<0,05) dos tempos de coleta nos níveis sanguíneos de triglicerídeos e ureia. As diferentes fontes proteicas também não influenciaram (P>0,05) os níveis séricos das enzimas gama glutamina transferase, creatina quinase e aminotransferase, com médias de 26,76±8,02; 112,13±31,72 e 58,79±20,13 UI/L, respectivamente. As fontes proteicas promoveram alterações na glicemia com os tempos de coletas, sendo que estes alteraram os valores de triglicerídeos e ureia. Não foram observadas alterações para os demais metabólitos sanguíneos.

SUMMARY The present work aimed to evaluate the effect of supplementation with different protein sources in the diets for dairy cows kept on Brachiaria brizantha MG5 grass pasture on serum levels of the glucose, triglycerides, cholesterol and urea as well as on enzymes gama grutamil transferase, creatinine quinase and aminotransferase. We have evaluated the following protein sources: bean byproduct, soybean meal, sunflower meal and cottonseed meal. Eight crossbred cows (Holstein x Gir) were used, weighing 500±60.33 kg, average milk production of 14.85±3.28 kg/day, between the 60th and the 90th day of calving, by a simultaneous double 4 x 4 latin square design 4 x 4. Each experimental period lasted 15 days, of which the first 10 days were designed to animal adaptation and the final five days for data collection. There was an interaction effect (P<0.05) among protein sources and sampling time on serum glucose. There was no effect (P>0.05) of protein sources for the triglycerides, cholesterol and urea levels, averaging 6.46±2.05, 182.43±37.52 and 38.20±12.29 mg/dL, respectively. There was a significant effect (P<0.05) of the sampling time on blood levels of triglycerides and urea. The different protein sources did not affect significantly (P>0.05) serum enzyme levels of glutamine transferase, creatinine quinase and aminotransferase, averaging 26.76±8.02, 112.13±20.13 and 58.79±31.72 IU/L, respectively. The protein sources promoted changes on blood glucose with the sampling time, while sampling time altered triglycerides and urea levels. Changes to other blood metabolites were not observed.

Resumo Objetivou-se avaliar a influência da idade de corte no valor nutritivo de silagem de capim-piatã em monocultivo e em consórcio com sorgo. Utilizou-se o delineamento em blocos casualizados com quatro repetições. Os tratamentos foram dispostos em esquema de parcelas subdivididas, como parcelas sistemas (capim-piatã; sorgo de corte e pastejo e consórcio) e como subparcelas as idades de corte (70, 90 e 110 dias após a semeadura). Os minissilos foram abertos aos 46 dias, avaliando-se na silagem os teores de proteína bruta (PB), fibra em detergente ácido (FDA), fibra em detergente neutro (FDN), nutrientes digestíveis totais (NDT), nitrogênio amoniacal, lignina e pH. Com o avanço da idade, ocorreu redução linear no teor de PB de 0,12; 0,08 e 0,16 unidades percentuais a cada dia após a semeadura nas silagens de sorgo, sorgo+capim e capim-piatã, respectivamente. Verificou-se aumento linear no valor de pH da silagem de sorgo + capim, em função do avanço na idade de 0,03 unidade a cada dia após a semeadura. Nas silagens de sorgo e de capim em monocultivo, o pH apresentou valores médios de 4,63 e de 5,20, respectivamente. Os sistemas com sorgo apresentam potencial para produção de silagem de boa qualidade aos 70 dias de idade.

Abstract The objective of this study was to evaluate the influence of the time of cutting on the nutritive value of Piatã silage grass in monocrop and intercropping with sorghum for cutting and grazing. We used a randomized block design with four replications. Treatments were arranged in a split plot design, with systems as plots (Piata grass, sorghum for cutting and grazing, and intercropping), cutting ages as sublots (70, 90, and 110 days after sowing). The minisilos were opened at 46 days to evaluate silage crude protein (CP), acid detergent fiber (ADF), neutral detergent fiber (NDF), total digestible nutrients (TDN), ammonia nitrogen, lignin, and pH. We observed significant interaction between system and age on the variables CP, ADF, NDF, lignin and pH. With the advancement of age, there was a linear reduction in crude protein content of 0.12, 0.08, and 0.16 percentage units for each day after sowing in sorghum silage, sorghum grass and grass + Piata, respectively. There was a linear increase in the pH value of sorghum silage + grass due to the advancement of age of 0.03 units for each day after sowing. In sorghum silage and monocrop grass, the pH did not vary with the cutting age, with values of 4.63 and 5.20, respectively. Sorghum systems showed potential for the production of good quality silage at 70 days of age.

RESUMO Objetivou-se avaliar os efeitos do farelo de arroz sobre as perdas por gases e efluente, o perfil fermentativo e a composição química das silagens de Brachiaria decumbens cv. Basilisk ensilado em silos de laboratório. Utilizou-se delineamento inteiramente casualizado, com cinco tratamentos: 0; 10; 20, 30 e 40g/kg de farelo de arroz, com base na matéria natural da gramínea. Os valores das perdas por gases e efluentes foram reduzidos linearmente em 0,11 e 0,39g/kg MS, enquanto a recuperação da matéria seca aumentou linearmente em 0,32g/kg MS. Houve comportamento quadrático nos valores de pH e, redução linear para os valores de N-amoniacal e poder tampão, estimados em 1,1 e 0,5g/kg MS. As concentrações de ácido acético, butírico e propiônico foram reduzidas linearmente em 0,1; 0,008 e 0,006g/kg MS, enquanto a de ácido láctico aumentou linearmente em 0,5g/kg MS. Cada unidade porcentual de farelo de arroz promoveu aumento linear de 4,3; 1,8; 7,1 e 7,0g/kg nos teores de matéria seca, proteína bruta, extrato etéreo e nutrientes digestíveis totais, e redução linear de 6,9; 4,3 e 2,6g/kg MS nos teores de fibra em detergente neutro, fibra em detergente ácido e hemicelulose. A inclusão de 10g/kg de farelo de arroz já assegura diminuição das perdas por gases e efluentes, aumento na recuperação de matéria seca, proporcionando melhorias no perfil fermentativo e na composição química das silagens.

SUMMARY The objective was to assess the effects of rice meal over losses by gas and effluent, the fermentative profile and the chemical composition of Brachiaria decumbens cv. Basilisk silage in laboratory bags. Entirely random lining was used, with five treatments: 0; 10; 20; 30 and 40g/kg rice meal, based on natural grass matter. The values of losses by gas and effluents were reduced linearly in 0.11 and 0.39g/kg DM, while recovery of dry matter increased linearly in 0.32g/kg DM. There was quadratic behavior for pH values and linear decrease for the values of N-ammoniacal and buffering power estimated in 1.1 and 5g/kg DM. Concentrations of acetic, butyric and propionic acids were reduced linearly in 0.1; 0.008 and 0.006g/kg DM, while lactic acid increased linearly in 0.5g/kg DM. Each 1g/kg rice meal promoted linear increase of 4.3; 1.8; 7.1 and 7.0g/kg dry matter levels, crude protein, ethereal extract and total digestible nutrients and linear decrease of 6.9; 4.3 and 2.6g/kg DM of fiber in neutral detergent, fiber in acidic detergent and hemicellulose levels. Inclusion of 10g/kg rice meal already ensures lowering losses by gas and effluents, increase in dry matter recovery, allowing improvements on the fermentative profile and the chemical composition of silage.

ResumoObjetivou-se conduzir estudo colaborativo para avaliação do teor de matéria seca em alimentos em seis laboratórios de análise de alimentos de instituições integrantes do Instituto Nacional de Ciência e Tecnologia de Ciência Animal (INCT-CA). Avaliaram-se seis alimentos: cana-de-açúcar, silagem de milho, capim-elefante, farelo de soja, polpa cítrica e mistura de milho grão com ureia (9:1). Solicitou-se a cada laboratório análises das amostras por onze dias, consecutivos ou não, sendo realizadas três repetições por amostra por dia de avaliação. Observou-se variação entre laboratórios, dias de análise e efeito de interação de material e laboratório. Avaliação comparativa das médias produzidas pelos laboratórios e pelo método de Karl Fischer indicou que 11,1% das avaliações foram exatas. A variação dos resultados entre laboratórios correspondeu de 54,1 a 79,2% da variação aleatória total. Verificou-se que a repetibilidade representou de 6,24 a 26,45% da reprodutibilidade. Observou-se razões de Horwitz inferiores a 2 para os materiais avaliados. Percebeu-se que 52,8% das avaliações apresentaram variações das estimativas em função do dia no qual a análise foi realizada. Elevada variabilidade inter-laboratorial foi verificada por intermédio da avaliação dos questionários enviados aos laboratórios para elucidação dos principais procedimentos adotados, evidenciando possíveis causas da alta variação dos resultados.

AbstractThe objective was to conduct a collaborative study to evaluate the dry matter contents in feeds in six feed analysis laboratories from institutions linked to the National Institute of Science and Technology in Animal Science (INCT-CA). Six feeds were evaluated: sugarcane, corn silage, elephant grass, soybean meal, citrus pulp, and corn mixed with urea (9:1). It was asked to each laboratory that the samples were analyzed for eleven days, consecutive or not, with three replicates per sample per day of evaluation. There were variations among laboratories, days of analysis and interaction effect of material and laboratory. Comparative evaluation between the average contents produced by the laboratories and the Karl Fischer method indicated that 11.1% of the assessments were found accurate. The variation of results among laboratories accounted from 54.1 to 79.2% of the total random variation. It was found that the repeatability represented 6.24 to 26.45% of reproducibility. There are Horwitz ratios less than 2 for all materials tested. It was noticed that 52.8% of the assessments show variations of the estimates as a function of days in which analysis was performed. High inter-laboratory variability was checked through the evaluation of questionnaires sent to laboratories to elucidate the main procedures used in each laboratory, which can possible explain the great variation of the estimates obtained here.

ResumoO estudo foi realizado para avaliar se a restrição calórica ou proteica em fêmeas lactantes influencia o início da puberdade de seus cordeiros. Foram utilizados 21 cordeiros, sendo duas fêmeas e cinco machos por tratamento. Durante sessenta dias as mães receberam o tratamento aleatoriamente escolhido para o seu cordeiro: controle (TC, mantença), restrição calórica (TRC, ½ da energia do TC) e restrição proteica (TRP, 1/3 da proteína do TC). Após o desmame, os cordeiros receberam uma dieta composta por silagem de milho e concentrado, sendo pesados e avaliados quinzenalmente. Nos machos, coletava-se o ejaculado, mensurava-se circunferência escrotal e as dimensões testiculares. Nas fêmeas, realizava-se ultrassonografia para medir os ovários e verificar presença de corpo lúteo. Os machos eram considerados púberes se apresentassem ejaculado com, no mínimo: motilidade de 50%, concentração do ejaculado de 50 x 106espermatozóides/mL e, no máximo, 50% de anormalidades espermáticas totais, e as fêmeas, se apresentassem corpo lúteo. Foi encontrada interação entre período de avaliação e tratamento para circunferência escrotal (p=0,0019), volume testicular médio (p=0,0025), motilidade (p<0,0001) e concentração espermática (p=0,027), sendo o TRP, mais tardio do que TRC e TC em todas variáveis. Nas borregas não houve diferença (p>0,05) entre os tratamentos quanto às características foliculares, porém houve quanto ao corpo lúteo (p=0,0179). Notou-se que as fêmeas do TC apresentaram corpo lúteo a partir da 10a semana, TRC da 11a e o TRP da 13a. Concluiu-se que a restrição proteica materna durante a lactação atrasa o início da puberdade de seus cordeiros.

AbstractThis study was carried out to evaluate if caloric or protein restriction in lactation ewe affect puberty beginning of its lambs. Had been used 21 lambs, two females and five males per type of treatment. During 60 days the mothers received the treatment for which its lamb was sort out: Control Treatment (TC, maintenance), Energy Restriction Treatment (TRC, ½ of the energy of the TC) and Protein Restriction Treatment (TRP, 1/3 of the protein of the TC). The lambs were weaned and received a diet composed by corn silage and concentrate, weighed and evaluated fortnightly. In males, the ejaculate was collected, scrotal circumference and testicular size measured. In females, it was realized ultrasound to measure the ovaries and verify the corpus luteum presence. For males was considered in puberty if produced ejaculation with at least: motility of 50%, sperm concentration of 50 x 106espermatozoa/mL and maximum of 50% total sperm abnormalities, and females if exhibit corpus luteum. An interaction was found between evaluation period and treatment for scrotum circumference (p=0.0019), testicular volume (p=0.0025) sperm motility (p<0.0001) and concentration (p=0.027), TRP was later than TRC and TC in all variable. In female no treatment effect (p>0.05) were found about follicles characteristics, however that was difference in the presence of corpous luteum (p=0.0179). The TC females showed corpus luteum from the 10th week, TRC 11th and 13th for TRP. It was concluded that mother protein restriction during the lactation delays the beginning of the puberty of its lambs.

The objective of this experiment was to evaluate the losses of nutrient through gases and effluents, the nutrient recovery, fermentation parameters and the chemical parameters of silages of Brachiaria decumbens with the addition of soybean hulls, testing five levels of inclusion: 0, 10, 20, 30 and 40% (as is), with five replications per treatment. After the standardization cut of the forage, performed at 5 cm from the soil level, the soil was fertilized with nitrogen and potassium in the form of ammonium sulfate and potassium chloride, respectively, at 60 kg/ha. After 60 days, the grass was cut at 10 cm from the soil and ensiled. Experimental silos with capacity of 10 liters with Bunsen valve were used. Silos had 3 kg of sand conditioned at the bottom for retention of the effluents. The results show that the contents of dry matter, crude protein, acid detergent insoluble fiber and total digestible nutrients presented positive linear behavior with the inclusion of soybean hulls. In the grass silages with addition of soybean hulls, there was greater recovery of dry matter in relation to the control silage, which is a reflection of the negative linear behavior for the values of losses of gases and effluent. There was quadratic behavior in the pH values and negative linear behavior for the ammonia N values and buffering capacity with the inclusion of the additive in the grass silage. Inclusion of soybean hulls is sufficient to improve the fermentation pattern and minimize the losses through gases and effluents, contributing to the nutrient recovery, in addition to promoting overall improvement of the nutritional value of Brachiaria grass silages.

The objective of this study was to evaluate the processing of millet grain provided at two supplementation frequencies for grazing beef cattle during the dry season on nutritional parameters. Five rumen-cannulated crossbred steers, with 24 to 26 months of age and average body weight of 428.6±26.06 kg, were assigned to a Latin square design (5 × 5) in a 2 × 2 + 1 factorial arrangement, as follows: two forms of millet grain (whole grains - or ground; WG - GG), two strategies of concentrate supplementation (daily distribution - 7X; or three times a week - 3X) and a control treatment (mineral mixture - MM). Animals were kept in five paddocks of 0.24 ha each with Marandu grass pastures. Concentrate supplements were supplied at 2.00 and 4.66 kg/animal/day for treatments 7X and 3X, respectively. The concentrate supplementation enhanced the intake of total dry matter (DM) and organic matter (OM) and nutrients compared with mineral supplementation. No differences were found between dry matter intake and forage organic matter intake. The values of digestibility coefficients of DM, OM, ether extract, total carbohydrates and non-fiber carbohydrates were increased by concentrate supplementation. Regarding concentrations of rumen ammonia nitrogen, the interactions among time × treatment × day and day × treatment had effects on the measurements of ruminal pH. Plasma urea nitrogen, urinary urea excretion and urinary urea N excretion differed only between MM treatment and the others, with no interference of grain physical form and supplementation frequency on those variables. The millet grain processing does not alter forage intake, but improves digestibility. Daily supplementation increases digestibility of dry matter and neutral detergent fiber.

This experiment was conducted to evaluate the protein and carbohydrate fractions, and to estimate the in situ rumen degradation kinetic parameters of Brachiaria decumbens grass silage with inclusion of rice bran. Five rice bran inclusion levels were tested: 0, 10, 20, 30 and 40% of the natural matter, distributed into a completely randomized design with five replications. The brachiaria grass was obtained at 60 days of regrowth by cutting the forage at 10 cm from the soil and ensiling it in 10-L experimental silo bags, which were opened after 40 days. The degradability profiles for DM, CP, NDF and of the feeds for each animal utilized made it possible to obtain the estimates of the parameters analyzed. The contents of total carbohydrates (TCH), fibrous carbohydrates and fraction A+B1 of the TCH decreased linearly as the rice bran levels were elevated. Fraction A of the protein was increased linearly by 0.64% for every 1% of rice bran added to the silage. For nitrogenous fractions B3 and C, there was a decrease of 0.11 and 0.40% for each 1% of rice bran added to the silage, respectively. For the rumen degradability parameters of the dry matter, fractions A and I had estimated increases of 0.54 and 0.04% for every 1% inclusion of rice bran. For the degradation rate of fraction B (c), treatments had no effect. Fractions A and I of the crude protein degradability parameters increased by 0.22 and 0.72%, respectively, with inclusion of 1% rice bran. Inclusion levels of rice bran had no effect on fraction D, on the degradation rate of fraction B (c) or lag time (L) estimated for neutral detergent fiber. Inclusion of 10 and 20% rice bran in the brachiaria grass silage improves protein and carbohydrate fractions and rumen degradation kinetic parameters of dry matter, crude protein and neutral detergent fiber.

The objective of this study was to evaluate the effects of total digestible nutrient (TDN) levels in supplements on rumen pH, ruminal ammonia nitrogen concentration, intake and digestibility, nitrogen balance and microbial efficiency in beef cattle grazing on Marandu grass during the rainy season. The supplements comprised a mineral mixture, ground corn grain, soybean hulls, roasted soybeans and urea:ammonium sulfate. The mineral mix (MM) and supplements were supplied at 800, 1,600 and 2,400 g/animal/day, contained 500, 1,000 and 1,500 g of TDN, respectively, and were termed S500, S1000 and S1500. Supplemental crude protein (CP) was fixed at 300g animal/day for all supplementing strategies. Four crossbred rumen-fistulated steers, with an average weight of 512kg, were utilized. The animals were distributed in a 4×4 Latin square in four paddocks of 0.25 ha. The rumen nitrogen concentration was increased by 63% after four hours of supplementation. Supplements with increased TDN levels did not alter the total dry matter and forage intakes, although the TDN levels linearly increased the non-fibrous carbohydrates intake. Additionally, most supplements did not alter the digestibility of the diet nutrients.The nitrogen balance was similar in all treatments. However, supplements with the highest TDN levels linearly improved the microbial efficiency of finishing beef cattle that were pasture-grazed during the rainy season. Supplements with in creasing TDN levels improve the microbial efficiency during the rainy season.

Objetivou-se avaliar a influência da idade de corte sobre a produtividade e valor nutritivo de capim-piatã e sorgo de corte e pastejo, em sistema de integração lavoura-pecuária. O experimento foi realizado na Embrapa Gado de Corte, Campo Grande, Estado do Mato Grosso do Sul, no período de abril a outubro de 2009. Utilizou-se o delineamento em blocos ao acaso, com quatro repetições. Os tratamentos foram dispostos em esquema de parcelas subdivididas, com três sistemas de cultivo na parcela (capim-piatã em monocultivo; sorgo de corte e pastejo em monocultivo; consórcio de sorgo de corte e pastejo + capim-piatã), e três idades de corte na subparcela (70, 90 e 110 dias após a semeadura). As variáveis avaliadas foram: características agronômicas, produtividade e valor nutritivo. Observou-se efeito da idade de corte, independente dos sistemas avaliados nas variáveis de características agronômicas e digestibilidade in vitro da matéria orgânica (DIVMO). A produtividade foi de 4.048 kg ha-1 no sistema de integração. Independentemente da idade de corte, o sorgo em monocultivo apresentou os maiores teores de proteína bruta (PB). A integração de sorgo e capim-piatã foi vantajosa para produtividade de forragem. Aos 70 dias após a semeadura, as forrageiras apresentaram maior teor de PB e DIVMO.

The influence of cutting age on production and nutritive value of piatã grass (Brachiaria brizantha cv. BRS Piatã) and hybrid sorghum (Sorghum spp. cv. BRS 801) under an integrated crop-livestock system was evaluated. The trial was carried out at the Embrapa Beef Cattle (20º27' S; 54º37' W) in Campo Grande, Mato Grosso do Sul State, Brazil, between April and October 2009. Experimental design consisted of randomized blocks with four replicates. Treatments were distributed across a split-plot design, which included three production systems (single piatã grass; single hybrid sorghum; mixed cultivation of sorghum and piatã grass). Half-plots consisted of three forage ages at harvest (with 70, 90 and 110 days after seeding). Variables included agronomical characteristics, productivity and nutrition value. Regardless of the evaluated systems, cutting age affected agronomical characteristics and in vitro digestibility of organic matter (IVDOM). Production was highest (4,048 kg ha-1) within the integrated system. Regardless of cutting age, monoculture sorghum had the highest crude protein level. Results showed that integrated sorghum and piatã grasses were an asset for forage productivity. Forages had higher values in crude protein and in in vitro digestibility of organic matter on the 70th day after seeding.

O objetivo deste trabalho foi avaliar o efeito da substituição parcial do milho por fontes energéticas alternativas, em suplementos concentrados para bovinos de corte mantidos em pasto de Urochloa brizantha cultivar Marandu, durante o período das águas, no consumo e na digestibilidade aparente total dos alimentos. Foram utilizados cinco bovinos Nelore com peso médio corporal inicial de 367,8±4,31 kg. Utilizou-se o delineamento experimental quadrado latino 5x5, com cinco animais e cinco tratamentos. Foram avaliados: suplementos concentrados isoproteicos, com 30% de proteína bruta, formulados à base de grãos de milho, de milheto e de sorgo, e casca de soja; e um suplemento mineral (controle). Não foram observadas diferenças significativas no consumo de matéria seca (MS) total e de matéria orgânica (MO) entre os animais que receberam suplementação mineral e os que receberam suplementação concentrada; no entanto, estes últimos apresentaram menor (12,28%) consumo de MS de pasto. A suplementação concentrada aumentou o coeficiente de digestibilidade aparente total da MS, da MO, da proteína bruta e dos carboidratos não fibrosos que não foram influenciados pelas fontes de energia. Os grãos de milheto e de sorgo e a casca de soja podem ser utilizados em substituição parcial ao milho, na formulação de suplementos concentrados, sem prejudicar o consumo e a digestibilidade dos nutrientes da dieta.

The objective of this work was to evaluate the effect of the partial replacement of corn by alternative energy sources in concentrate supplements for beef cattle kept on Urochloa brizantha cultivar Marandu pasture, during the rainy season, on feed intake and total apparent digestibility. Five Nellore cattle with initial average body weight of 367.8±4.31 kg were used. The experimental design was a 5x5 Latin square, with five animals and five treatments. The following were evaluated: isoproteic concentrate supplements, at 30% crude protein, formulated with corn, millet, and sorghum grains, and soybean hulls; and a mineral supplement (control). No significant differences were observed in total dry matter (DM) and organic matter (OM) intake between the animals fed mineral supplementation and those receiving concentrate supplementation; however, the latter showed the lowest (12.28%) pasture DM intake. Concentrate supplementation increased the coefficient of total apparent digestibility of DM, OM, crude protein, and of non-fiber carbohydrates that were not affected by the energy sources. Millet and sorghum grains, and soybean hulls can be used to partially replace corn in the formulation of concentrate supplements without affecting intake and digestibility of dietary nutrients.

O objetivo deste trabalho foi avaliar os efeitos da inclusão da torta de girassol na dieta de cordeiros em confinamento sobre o desempenho produtivo dos animais. Utilizaram-se 40 cordeiros sem raça definida, não castrados, com peso médio inicial de 20,17±2,66 kg, alimentados com 0, 7, 14, 21 e 28% de torta de girassol na dieta (base seca). O experimento foi conduzido em delineamento de blocos ao acaso. A inclusão de torta de girassol na dieta não alterou o consumo médio de matéria seca (883,58 g por dia), a conversão alimentar (4,40) e o consumo médio de água (2,59 L por dia). O aumento dos níveis de torta de girassol diminuiu linearmente o peso final, o ganho de peso total, o ganho de peso diário e a área de olho de lombo. O nível de inclusão de até 28% não afeta o consumo médio de matéria seca e de água, mas reduz o desempenho e a área de olho de lombo. Para obter o menor custo com a dieta, o nível de inclusão da torta de girassol pode atingir até 28% da matéria seca, quando o seu preço representar até 40% do preço da mistura entre milho e farelo de soja.

The objective of this work was to evaluate the effects of inclusion levels of sunflower meal in feedlot lamb diets on animal productive performance. Forty crossbreed lambs, not castrated, with average initial body weight of 20.17±2.66 kg were feed levels of 0, 7, 14, 21, and 28% of sunflower meal in the diet (dry basis). The experiment was carried out in a randomized complete block design. The inclusion of sunflower meal in the diet did not affect average dry matter intake (883.58 g per day), feed conversion (4.40), and average water intake (2.59 L per day). The increase in the levels of sunflower meal linearly reduced final weight, total weight gain, average daily gain, and loin eye area. The inclusion level of up to 28% does not affect the average intake of dry matter and water, but reduces animal performance and loin eye area. To obtain the lowest cost with the diet, the inclusion level of sunflower meal can reach up to 28% of dry matter, when its price represents up to 40% of the price of corn and soybean meal blend.