Fontes de energia em suplementos múltiplos para recria de novilhos mestiços em pastejo durante o período de transição seca/águas: desempenho produtivo e características nutricionais

Abstract

Energy sources in multiple supplements for growing crossbred steers on pasture during the dry to rainy seasons: performance and nutritional characteristics ABSTRACT -This study was conduced to evaluate the energy sources, rich in starch or fiber in multiples supplements on performance and nutritional characteristics of finishing crossbred steers in the dry/rainy transition season, grazingBrachiaria decumbens Stapf. The experimental area was divided into 5 paddocks with 2.0 ha each, with dry matter availability of 4.309,4 kg/ha. Twenty-four castrated crossbred steers were used, initially 24 month old and 314.46 kg. For each animal, one of the five treatments was randomly applied: mineral mixture ad libitum, pearl millet grain or corn grain, as starchy energy sources, citrus pulp or wheat bran, as fibrous energy sources. To the different energy sources, the following were added: mineral mixture, cotton seed meal and urea, so that they composed supplements with 30% of crude protein based on the natural matter, supplied at the level of 1.5 kg/animal/day. In relation to control group, significant effect of the supplementation on the diary gain was not verified. The average daily gain obtained with the fibrous sources was 17.43%higher than that obtained with the starchy sources. The dry matter (DM), organic matter, non-fibrous carbohydrates (NFC), crude protein (CP), ether extract, digestible DM, total digestible nutrients and neutral detergent fiber (NDF) indigestible intakes (kg/animal/day) was higher for supplemented animals in relation to the control group. CP and NFC total apparent digestibility were lower for animals that received only MM. Excretion of urea by urine, and the urea plasmatic level were lower for animals fed MM only. Multiple supplements with high digestible fiber sources in association with urea promoted better performance to the animals than that formulated with starchy sources and urea. The supplementation in the dry/rainy season, in 0.4% of the BW do not affect the NDF digestibility, regardless of the energy source.

Levels of multiple supplements or nitrogen salt for beef heifers in pasture during the dry season

“…For every 1 kg of protein supplement ingested, there was a 60% increase in microbial protein synthesis compared with control. Nascimento et al (2009), when working with crossbred steers supplemented with 0.4% BW (30% CP) during the 1 S = non-supplemented versus supplemented; NS = nitrogen salt versus multiple supplementation; L and Q = linear and quadratic order effects on multiple supplementation levels, which involves only information from levels of multiple supplement; 2 / (ns), (*), (**) and (***) = non-significant (P>0.10) and significant at the levels of 0.10, 0.05 and 0.01 of probability by the F test, respectively; 3 calculated by equation proposed by Detmann et al (2006) Table 6 -Least square means for apparent digestibility dry-rainy transition period, observed that the supplemented animals obtained Nmic production 34.4% higher than the control animals. A similar behavior was observed in this study, in which for the estimated level of multiple supplement (45% CP) OF 0.4% BW (800 g/day), 48% of production superiority was found in Nmic production when compared to control animals.…”

<b>Performance of beef cattle bulls in feed lots and fed on diets containing enzymatic complex

“…Prolamin, a protein in the maize grain that wraps starch granules, is another factor that may jeopardize starch granules in cereals (Chandrashekar & Mazhar, 1999). The protein occurs in the endosperm (30 -60% of total grain protein) and envelops and turns impervious starch granules in a hydrophobic matrix, making difficult the access of microorganisms and their enzymes in the granule (Nascimento et al, 2009).…”

Níveis de suplemento energético para bovinos em pastagens tropicais e seus efeitos no consumo de forragem e fermentação ruminal

“…Não houve efeito (P>0,05) da suplementação no nitrogênio uréico no plasma (NUP). Os níveis variaram entre 10,58 e 16,70 mg/dL, e estão dentro dos valores encontrados na literatura com gado de corte pastejando forrageiras tropicais (NASCIMENTO et al, 2009;NASCIMENTO et al, 2010;MORAES et al, 2009). Magalhães et al (2005) Os valores de lag time, DE, c e I obtidos neste trabalho foram semelhantes aos encontrados por Danés (2010), que ao avaliar as mesmas variáveis para o capim Elefante, relatou valores entre 4,8 e 6,4 (lag time), 47% (DE a 2%/h), 4,4 e 5,0 (c) e 20% (I).…”

“…Porém no que se referem à degradabilidade potencial, os valores encontrados neste estudo, apresentam-se mais elevados do que os encontrados por alguns autores (DANÉS, 2010;CARVALHO et al, 2008;OLIVEIRA et al, 2010) 2001; Sales et al (2008aSales et al ( , 2008b; Nascimento et al (2010Nascimento et al ( , 2009; Lardy et al 2004 4.7 Cinética de fermentação ruminal in vitro "gás"…”