The objective of this study was to estimate and evaluate the contents of apparently digestible fractions of crude protein, ether extract and non-fibrous carbohydrates, the digestible fraction of the neutral detergent fiber and the content of total digestible nutrients (TDN) from the chemical composition of feeds in growing cattle fed different diets. Fourteen F1 Red Angus × Nellore young bulls with average age and weight of 12 months and 287±36 kg were used. Animals were fed elephant grass silage, corn […]

The objective of this study was to evaluate the chemical composition of the forage apparently consumed by steers in a natural grassland on region of Campanha, in Rio Grande do Sul, Brazil, subjected or not to different inputs: NP – natural pasture without inputs; FNP – fertilized natural pasture and INP – improved natural grassland with fertilization and over-seeded with cultivated winter species. Three Angus steers testers and a variable number of regulator animals per experimental unit were utilized in […]

It was evaluated the effect of the absence and of application of three nitrogen doses (50, 100 and 200 kg ha-1of N) and four harvest times in the winter/spring season (from July to October) on dry mass yield (DMY), on the relative chlorophyll contents (ICF _ leaf chlorophyll index) and on the contents of total digestible nutrients (TDN), crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF) and lignin, and their respective correlations on Tanzania and Mombaça grasses […]

The objective of this work was to evaluate the equations adopted by the NRC and Detmann to estimate the energy content of agricultural and agroindustrial byproducts. It was evaluated byproducts of pineapple, cocoa, palm oil, beans, sunflower, guava, cassava bark, cassava stem, raw cassava, papaya, mango, passion fruit, turnip and corn gluten meal. All animals received corn silage and the mixture urea/ammonium sulfate (9:1) so rations with the two levels of each byproduct remained isonitrogenous. Among the models for digestible […]

It was evaluated in this work, crop yield, fermentative quality and nutritional value of the silage of cultivars of white (Avena Sativa L.) and black (Avena Strigosa Schreb) oats cut at two development stages. It was used an experimental randomized block design in a 4 x 2 factorial scheme, consisting of four oat cultivars (two cultivars of black oats: Aveia Preta Comum and UTFP 971; and two cultivars of white oats: ER 91156- 1- 2- 1 and SI 98105- b), […]

The objective of the present study was to evaluate the digestibility, intake, performance and carcass characteristics in young crossbred bulls fed balanced diets based on sugarcane or sorghum silage. In the digestibility assessment in the feedlot, four and eighteen young crossbred young bulls were used per diet, kept in individual stalls, in a randomized complete experimental design with two diets (sorghum silage + 1.0% live weight in concentrate and chopped sugar cane + 1.2% of live weight concentrate). The diets […]

A trial involving 27 zebu bulls at pasture with initial live weight (LW) of 311.0 kg were conducted with the objective of determining their energy requirements. Three animals were slaughtered at the beginning of the trial, performing the reference group; four had restricted grazing time to limit the energy intake to a level close to the maintenance level. The remaining were uniformly allotted to a complete randomized design, into four treatments: mineral mix, self-feeding protein and protein suplementation three times […]

The objective of this study was to evaluate the estimates of the digestible fraction of neutral detergent fiber (NDF) in cattle using the Surface Law approach. The prediction model used in this study was similar to that proposed by the NRC (2001). The following model parameters were used: lignin protection factor on cell wall carbohydrates (LPF) and digestibility coefficient of potentially digestible NDF (DCPNDF). Two estimate sets of these parameters were evaluated. The first set was called Weiss Model (WM) […]

Four crossbred Holstein x Zebu steers fitted with ruminal and abomasal cannulas were randomly assigned to a 4 x 4 Latin square to evaluate the effects of feeding corn or sorghum silages with and without microbial inoculant on intake, ruminal metabolism, total and partial digestibility of nutrients, and digesta passage rate. Diets contained, dry matter (DM) basis, a forage to concentrate ratio of 63:37. No significant differences were observed on the intakes of DM, crude protein (CP), and total digestible […]

The objective of this study was to estimate the dietary apparent digestible fraction of nonfiber carbohydrates (NFC) using the Lucas test concept. The dataset contained a total of 167 observations with 57 originated from two trials conducted with lactating cows and 110 from three experiments with growing and finishing cattle. The dataset was randomly divided in two subsets. The first subset was used to estimate the model parameters while the second for model validation. Tests for checking equality of models […]