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This study aimed to evaluate the performance of feedlot lambs fed diets formulated with hay of different genotypes of Cynodon spp. and to compare the dry matter digestibility of diets using different evaluation methods (total fecal collection and chromium oxide). Suffolk crossbred neutered male lambs (n=30), with an average age of 90 days and average body weight of 21.5 kg ± 1.6. Diets were formulated using a standard concentrate and hay of the following genotypes of Cynodon dactylon: Jiggs, Vaquero, Tifton 68, Coast-Cross, Tifton 85 and Russell, in a 60:40 forage concentrate ratio, composing the treatments distributed in a randomized block design in a factorial 5 x 2 arrangement of 5 diets and 2 digestibility evaluation methods. Animals receiving Vaquero hay showed dry matter intake of 18.3; 16.9; 25.6; 20.7 and 24.2% higher than those fed hay of Jiggs, Tifton 68, Coast Cross, Tifton 85 and Russell, respectively. There was no difference between diets for digestibility using total fecal collection, chromium oxide and final weight of animals. Jiggs hay based diets allowed greater daily weight gain and better feed conversion.

Four steers in individual paddocks with Marandu grass (B. Brizantha) in 4x4 square design were used to evaluate sunflower crushed supplementation in pasture-grazing animals on nitrogen balance and microbial protein synthesis. Supplements at 6 g kg-1 body weight comprised corn, soybean meal, and mineral and soybean meal substituted at proportions 0, 20, 40 and 60%. Diet contained averages 6.79, 6.96, 7.10 and 6.87% nitrogen respectively for substitution levels 0, 20, 40 and 60%. The inclusion of sunflower crushed (SC) increased nitrogen intake and fecal excretion of nitrogen while providing a positive balance. Animals’ plasma urea concentration supplemented with SC was 28.13% lower than that of supplemented animals without SC. SC inclusion did not change allantoin concentration, purine derivatives, microbial nitrogen, crude microbial protein and microbial efficiency microbial, with mean rates totaling 150.98 mmol day-1; 158.06 mmol day-1, 112.35 g day-1, 702.18 g day-1; 146.41 crude protein (CP) microbial kg-1 of TDN. Partial replacement of soybean meal by sunflower crushed improves nitrogen balance without altering microbial protein synthesis and excretion of urea and creatinine. Four steers in individual paddocks with Marandu grass (B. Brizantha) in 4x4 square designwere used to evaluate sunflower crushed supplementation in pasture-grazing animals on nitrogen balanceand microbial protein synthesis. Supplements at 6 g kg-1 body weight comprised corn, soybean meal, andmineral and soybean meal substituted at proportions 0, 20, 40 and 60%. Diet contained averages 6.79, 6.96,7.10 and 6.87% nitrogen respectively for substitution levels 0, 20, 40 and 60%. The inclusion of sunflowercrushed (SC) increased nitrogen intake and fecal excretion of nitrogen while providing a positive balance.Animals’ plasma urea concentration supplemented with SC was 28.13% lower than that of supplementedanimals without SC. SC inclusion did not change allantoin concentration, purine derivatives, microbialnitrogen, crude microbial protein and microbial efficiency microbial, with mean rates totaling 150.98 mmolday-1; 158.06 mmol day-1, 112.35 g day-1, 702.18 g day-1; 146.41 crude protein (CP) microbial kg-1 of TDN.Partial replacement of soybean meal by sunflower crushed improves nitrogen balance without alteringmicrobial protein synthesis and excretion of urea and creatinine

Thirty-six experimental silos arranged in a completely randomized 4 x 3 factorial design were provided to evaluate the chemical changes of sunflower silage treated with soybean hulls, sunflower crushed and urea at 14, 21 and 28 days of ensilage. The additives were based on 5% natural matter, whereas control consisted of silage with 100% sunflower plant. OM, NDIP, and MM had average rates 911.2; 86.6 and 92.9 g kg-1 of dry matter respectively. The addition of soybean hulls and sunflower crushed increased DM rates after 28 and 21 days. Urea increased nitrogen fractions and the addition of soybean hulls increased total carbohydrate content of silage by 5.1%, whereas the addition of sunflower crushed decreased the same by 2.18%. NDF, ADF and hemicellulose average rates were 625.4, 460.3 and 165.2 g kg-1 of DM. The addition of soybean hulls and sunflower crushed reduced the in vitro dry matter digestibility by 8.3 and 5.97%. The addition of 5% sunflower crushed and soybean hulls improved the nutritional value of sunflower silage and the addition of urea improved the protein rates. Para se avaliar as alterações bromatológicas da silagem de girassol com casca de soja, torta de girassol e uréia com 14, 21 e 28 dias de ensilagem, foram confeccionados 36 silos experimentais, em delineamento inteiramente casualizado num esquema fatorial 4 x 3. Os aditivos foram adicionados, na base de matéria natural de 5%; e o controle foi a silagem de 100% da planta de girassol. Os teores de MO, PIDN e MM, apresentaram médias de 911,2; 86,6 e 92,9 g kg-1 de MS. A adição de casca de soja e torta de girassol elevou o teor de MS após 28 e 21 dias. A uréia incrementou as frações nitrogenadas e, a adição de casca de soja proporcionou aumento no teor de carboidratos totais em 5,1% e a adição de torta de girassol, redução de 2,18%. Os teores médios de FDN, FDA e hemicelulose, foram de 625,4; 460,3 e 165,2 g kg-1 de MS. A adição de casca de soja e torta de girassol reduziu a digestibilidade in vitro da MS em, 8,3 e 5,97%. A adição de 5% de torta de girassol e de casca de soja melhora o valor nutricional da silagem de girassol e a adição de uréia o perfil protéico.

To evaluate the grass B. brizantha cv. Marandu, under grazing, we use three sampling methods: total availability (TA), hand plucked (HP) and extrusa (EXT) in a completely randomized design with four replications. The hand plucked method was collected manually after observing the behavior of grazing animals. TA was determined by cutting at ground level, using a metallic square (0.25 m²) and EXT was collected by rumen evacuation. The values for dry matter (DM), neutral detergent fiber (NDF) and acid detergent fiber (ADF), were 27.20, 88.52 and 43.70% in the treatment and HP, and 25.53, 87.70 and 45.50% in TA. The extrusa had the lowest DM content (15.88%) and higher crude protein (CP) (15.22%), possibly due to the presence of saliva. The levels checked for extrusa NDF, ADF and in vitro digestibility of dry matter were 81.98, 36.90 and 79.10%, demonstrating the selectivity of the animals. The high levels of FDA for TA reflect the composition of the forage with the high proportion of senescent material. The samples obtained by the total availability were not representative of the diet consumed by cattle. The different sampling methods influence the chemical composition of B. Brizantha cv. Marandu. Objetivou-se avaliar o capim B. brizantha cv. Marandu, sob pastejo, utilizando-se os métodos de coleta: disponibilidade total (DT), pastejo simulado (PS) e extrusa (EXT). O pastejo simulado foi colhido manualmente após observação do comportamento de pastejo dos animais. A DT foi determinada por meio de corte rente ao solo, com uso de um quadrado metálico (0,25 m²) e a EXT foi coletada por esvaziamento ruminal. Utilizou-se um delineamento inteiramente casualizado com quatro repetições. Os teores de matéria seca (MS), fibra em detergente neutro (FDN) e fibra em detergente ácido (FDA), foram de 27,20; 88,52 e 43,70% no tratamento PS e 25,53; 87,70 e 45,50% no tratamento DT. A extrusa apresentou o menor teor de MS (15,88%) e o maior teor de proteína bruta (PB) (15,22%), possivelmente em função da presença de saliva. Os teores verificados na extrusa para FDN, FDA e digestibilidade in vitro da matéria seca foram de 81,98; 36,90 e 79,10%, demonstrando a seletividade dos animais. Os altos teores de FDA no tratamento DT refletem a composição da forragem que apresentou elevada proporção de material senescente. As amostras obtidas pela disponibilidade total não foram representativas da dieta ingerida pelos bovinos. Os diferentes métodos de amostragem influenciam na composição bromatológica da B. Brizantha cv. Marandu.

Avaliou-se a degradabilidade in situ, dos grãos de linhaça, canola, colza e milho, caroço de algodão, e dos concentrados casca e farelo de soja, em ovinos. Foram utilizados três animais da raça Santa Inês, fistulados e providos de cânulas ruminais, mantidos em baias individuais, recebendo diariamente capim picado e ração concentrada. Os alimentos foram incubados em ordem decrescente de 72, 48, 24, 18, 6, 3 e 0h. O teor de proteína dos alimentos avaliados foram 34,77; 30,07; 23,70; 10,64; 26,12; 14,65 e 56,90% para canola, colza, linhaça, milho, caroço de algodão, casca de soja e farelo de soja, respectivamente. A canola e a colza apresentaram baixa degradabilidade efetiva para a MS, com valor médio de 33,68%. O grão de linhaça apresentou degradabilidade efetiva para a MS de 64,24%, com fração potencialmente degradável de 87,89%. O milho apresentou fração solúvel de 12,33% e uma degradação de 39,67% para a MS. O farelo de soja apresentou-se dentro dos parâmetros normais de degradação com 52,61% para a MS e 52,83% para PB. Para a linhaça, canola e colza a degradabilidade da proteína apresentou valor médio de 18,34%. Os grãos de avaliados apresentaram baixa degradabilidade efetiva para a matéria seca e proteína bruta. This study evaluated in situ ruminal degradability of grains of linseed, canola, rapeseed and corn, whole cottonseed, as well as soybean hulls and soybean meal, in sheep. Three Santa Inês sheep were fistulated and fitted with rumen cannulas. The animals were housed in individual stalls, receiving chopped grass and concentrated feed daily. Feeds were incubated in descending order of 72, 48, 24, 18, 6, 3 and 0h. Protein content was 34.77% for canola, 30.07% for rapeseed, 23.70% for linseed, 10.64% for corn, 26.12% for cottonseed, 14.65% for soybean hulls, and 56.90% for soybean meal. Canola and rapeseed showed low effective degradability of DM, with mean value of 33.68%. Linseed grain had DM degradability of 64.24%, with 87.89% potential degradable fraction. Corn grain showed soluble fraction of 12.33% and 39.67% degradation for DM. Soybean meal was within normal parameters of degradation, with 52.61% for DM and 52.83% for CP. For linseed, canola and rapeseed, average protein degradability value was 18.34%. The evaluated grains showed low effective degradability for dry matter and crude protein.

Performance of Steers Supplemented in Pasture with Protein-energy Mineral Salt in dry season. The research was carried out to evaluate the protein-energy effect of multiple supplements on animal production, N urea in plasmatic quantities and economic parameter of growing beef cattle in pasture during dry season. Thirty-two castrated beef cattle steers were divided into four groups of eight animals. They were analyzed according to a randomized block design at 5% of significance. Each group received one treatment to pasture with addition of mineral salt + urea + corn; mineral salt + urea + soybean meal; mineral salt + urea + corn + soybean meal. There was no difference (P>0.05) between supplements for daily LWG and for average metabolic weight. This can be justified by forage quality combined with availability of DM/ha. As for the variable N-urea in the blood, results indicated higher protein value as an effect of the 50 % addition of soybean meal in the treatment composition. The supplementation of animals in pasture with multiple supplements and low consumption allowed LWG benefits. Its use depends on the cost of the supplement and the price of the meat.

Made available in DSpace on 2015-02-02T12:39:30Z (GMT). No. of bitstreams: 0 Previous issue date: 2014-09-01Bitstream added on 2015-02-02T13:08:02Z : No. of bitstreams: 1 S1807-86722014000300015.pdf: 591230 bytes, checksum: 727f35c86f75cab982727d256ab79225 (MD5) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) O presente experimento foi conduzido com o objetivo de avaliar o efeito de suplementações sobre o desempenho produtivo e parâmetros econômicos de novilhos de corte, em fase de recria, manejados em pastagens durante a época da seca. Foram utilizados 24 novilhos castrados, com idade e peso médios de 18 meses e de 269 kg, respectivamente. Foram avaliados os seguintes tratamentos: pastagem sem minerais (P); pastagem e sal mineralizado (PSM) e pastagem e sal mineralizado mais ureia (PSMU). A composição bromatológica caracterizou-se por baixos conteúdos de proteína bruta e altos valores de fibra em detergente neutro e fibra em detergente ácido para forragens amostradas na forma de coleta completa comparada com a técnica de simulação de pastejo. Os animais sob os tratamentos com suplementação mineralizada mais ureia apresentaram ganhos de peso diários médios superiores (p < 0,05) ao daquele submetido apenas à pastagem. No entanto, quando o peso médio foi expresso em peso metabólico apenas o tratamento com ureia apresentou superioridade nos dados (p < 0,05). A suplementação de animais em pastejo mostrou-se uma técnica economicamente rentável, sendo que a utilização de sal mineralizado com ureia no período seco possibilita melhor desempenho a custos viáveis. The present study evaluated the effects of supplements on the productive performance and economical parameters of beef steers on pastures during the dry season. Twenty-four castrated steers with average age and weight of eighteen months and 269 kg, respectively, were evaluated in the following treatments: pasture without minerals (P); pasture and mineral salt (PMS) and pasture and mineral salt plus urea (PMSU). The chemical composition showed low contents of crude protein and high values of neutral and acid detergent fiber for forages sampled in the form of complete collection compared with the grazing simulation technique. The supplementation with mineral salt plus urea led to a higher average daily gain (p < 0.05) than the animals on pasture without mineral. However, when the average daily gain was expressed per metabolic weight, the supplementation with mineral salt plus urea was superior (p < 0.05). The supplementation of animals on pasture proved economically profitable, and the use of mineral salt with urea in the dry season enables a better performance at viable costs. Universidade Federal da Grande Dourados Faculdade de Ciências Agrárias Universidade Federal de Lavras Departamento de Zootecnia Centro Federal de Educação Tecnológica de Mato Grosso Universidade Estadual Paulista Júlio de Mesquita Filho Programa de Pós-graduação em Zootecnia Universidade Estadual Paulista Júlio de Mesquita Filho Programa de Pós-graduação em Zootecnia

The aim of this work was to determine ruminal degradation of neutral detergent fiber of grasses of the genus Cynodon, harvested at four cutting ages. It was used a randomized block design, with five treatments arranged in a split plot, the five evaluated genotypes: Tifton 85, Jiggs, Russel, Tifton 68 and Vaquero; were the plots and ages of cutting were the subplots: 28, 48, 63 and 79 days. By adding one day in the cutting age, there was a linear reduction in the effective degradability of neutral detergent fiber of blade and stem of 0.16 and 0.18%, respectively. The increase in the cutting age had a linear and positive influence on the undegradable neutral detergent fiber with daily increments for leaf and stem of 0.12 and 0.18%, respectively. At the 28 regrowth day, all genotypes showed higher content of potentially degradable insoluble fraction, effective degradability and lower undegradable fraction of the neutral detergent fiber of blade and stem in relation to other ages, in this way this interval is recommended for cutting management.