André Alves de Oliveira

Supplementation frequency and proteins sources for growing of steers in pasture during the dry season: productive and economical performance

Two experiments were carried out with the objective of evaluating the effects of the frequency of supplementation with two proteins sources on productive and economical performance (experiment 1) and the nutrients digestibility of steers in supplemented pasture during the dry season over a year. It was used twenty weaned zebu calves at the age of 10 months and initial live weight (LW) of 208.43 kg, distributed in four paddocks of Brachiaria brizantha cv. Marandu, each one with 1.6 ha. Both experiments were structured in 2 × 2 factorial arrangement with two supplements (with soybean meal and high energy cottonseed meal). There was no protein sources × supplementation frequency interaction for any of the economical and productive performance traits. The protein sources didn’t affect the daily average gain, but the frequency of supply affected performance, which was better in the animals under supplementation at three times a week (0.670 kg /day). The highest economic return was obtained with the offer of supplement with cottonseed meal three times a week. The frequency of supplementation affect the nutrients intake, while the protein source of the supplement had effect only on the ethereal extract intake, which was higher in the animals that consumed the supplement with cottonseed meal. The supplement with high energy cottonseed meal provided higher digestibility of diet crude protein. The supply of supplement three times a week, not only reduces the costs of supplementation, but it possibilities a higher performance than the one obtained with daily supplementation. The use of higher energy cottonseed meal in multiple supplements replacing soybean meal is satisfactory mainly under economical point of view.

Suplementação infrequente e fontes proteicas para recria de bovinos em pastejo no período seco: parâmetros nutricionais

The objective of this study was to evaluate the effects of protein sources and frequency of supplement offer on the intake and nutrient digestibility, on the concentrations of ammonia nitrogen (N-NH3), on rumen pH and on serum urea nitrogen concentrations in steers grazing pasture of Brachiaria brizantha cv. Marandu during the dry season. Five crossbred Zebu × Angus steers with initial live weight of 295 kg, castrated and fitted with rumen canullae were used in a 5 × 5 Latin square design. It was evaluated two isoprotein supplements, one with soybean meal (SM) and the other with high energy cottonseed meal, offered at two frequencies: every day (7 times a week), or 3 times a week (on Mondays, Wednesdays and Fridays); and a mineral mixture (MM). The supplementation increased the intake of CP, of ether extract (EE) and non-fibrous carbohydrates (NFC) in kg/day. The supplement with cottonseed meal increased the intake of ether extract. There was a positive effect of the three times a week supplementation on the intakes of total dry matter, of forage, of organic matter of forage, total carbohydrates (TC) and NDF. The supplementation reduced the digestibility of the NDF and increased the digestibility of the CP. The supplement with cottonseed meal reduced digestibility of NDF and total carbohydrates. Three times a week supplementation did not affect digestibility of the nutrients neither the rumen pH. Supplement intake increases concentrations of N-NH3, especially if it is carried out 3 times a week. Concentrations of urea nitrogen in the serum of growing steers increase.

Whole or ground millet grain provided in two supplementation frequencies for grazing beef cattle: nutritional parameters

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.

Total digestible nutrient levels in supplements for finishing steers in the rainy season: nutritional characteristics and microbial efficiency

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.

Suplementação de bovinos em sistema de pastejo : aspectos relacionados à forrag em e ao uso de fontes alternativas de energia para suplementos múltiplos

Este trabalho teve como objetivo demonstrar a importância da educacao ambiental em area natural e identificar como as atividades ecoturisticas praticadas no Mirante Camping e Lazer podem intervir na sensibilizacao ambiental dos visitantes, proprietarios e funcionarios. O Mirante esta localizado em area rural no alto da Serra Tapirapua, a aproximadamente 30Km do municipio de Tangara da Serra, apresentando uma area de 52,5 alqueires. O local recebe turistas desde 2005 e conforme observacao feita no empreendimento notouse uma estrutura fisicamente adequada para receber turistas e o desenvolvimento de atividades ecoturisticas como a caminhada por trilhas e observacao panorâmica de paisagens. Os trabalhos de campo deram inicio em marco de 2007, a fim de estabelecer um contado com os proprietarios e no periodo de marco a abril de 2008 foram aplicados 27 questionarios. Desses questionarios 23 foram aplicados aos visitantes e quatro aos proprietarios e funcionarios. Essa divisao ocorreu para analisar a percepcao ambiental em diferentes visoes (visitante e administracao). Nos resultados pode-se perceber que o Mirante e um lugar bastante frequentado por familias e casais e que essas pessoas estao, em sua maioria, tentando fugir do estresse provocado pelo trabalho e pela vida na cidade, vendo no mirante um refugio de muita tranquilidade.