The objective of this trial was to evaluate the effect of feeding fibrolytic enzyme (cellulose and xylanase) on intake and apparent total tract digestibility of nutrients in cattle receiving diets containing corn silage or Tifton 85 hay (Cynodon spp.). Eight animals fitted with ruminal cannulae and averaging 340 kg of body weight were randomly assigned to two replicated 4 x 4 Latin squares in a 2 x 2 factorial arrangement of treatments (forage sources with or without fibrolytic enzyme supplementation). […]

The effects of collection days on urinary excretion of creatinine and purine derivatives (PD), absorbed purines and microbial N synthesis (Nmic) were evaluated in different categories of Nellore cattle: heifers, steers, bulls and lactating cows. Yield of Nmic estimated from spot urine samples was compared to that obtained by total urine collection. Sixteen feedlot Nellore animals were assigned to a completely randomized design in a split plot scheme with treatments (two levels of concentrate [25 or 50%] and four categories […]

The objective of this trial was to evaluate the effect of fibrolytic enzymes (cellulase and xylanase) on particle passage rate, dilution rate and ruminal parameters (pH and ammonia N) in animals fed diets containing corn silage or Tifton 85 hay (Cynodon spp.). Eight bovines fitted with ruminal and duodenal cannulas were randomly assigned to two 4 x 4 Latin squares in a 2 x 2 factorial arrangement of treatments (two forage sources supplemented or not with fibrolytic enzymes). A commercial […]

It was investigated the effects of fibrolytic enzymes (cellulase and xylanase) on the microbial protein synthesis efficiency and enzymatic activity of b-1,4-endoglucanase (cellulase) in animals receiving diets with corn silage and Tifton 85 hay (Cynodon spp.). Eight bovines fitted with rumen and duodenum cannulas were randomly assigned to two replicated 4 x 4 Latin squares with a 2 x 2 factorial arrangement of treatments (two forage sources with or without fibrolytic enzymes). The commercial enzymatic complex used in this trial […]

Data of 320 animals were obtained from eight comparative slaughter studies performed under tropical conditions and used to estimate the total efficiency of utilization of the metabolizable energy intake (MEI), which varied from 77 to 419 kcal kg-0.75d-1. The provided data also contained direct measures of the recovered energy (RE), which allowed calculating the heat production (HE) by difference. The RE was regressed on MEI and deviations from linearity were evaluated by using the F-test. The respective estimates of the […]

The potential of the semi-automated in vitro gas production technique was evaluated by incubation of four hybrids of sorghum (BR700, BR701, BR601 and AG2002). The results of this experiment (in vitro dry matter digestibility, DMD) were compared with the apparent in vivo digestibility. The relationship between the dry matter digestibility obtained by the gas production technique after 96 hours of incubation and the apparent dry matter digestibility in vivo was demonstrated by the equation: in vivo digestibility (g/kg) = 0.46 […]

The objectives of this paper were estimate the energy values of feeds through equations proposed by NRC, from feed composition present in data base of “Brazilian Tables of Feed Composition for Cattle” and of a trial that used sheep, and validate those equations from observed values of TDN, digestible fractions of NDF (DNDF), crude protein (DCP), ether extract (DEE) and nonfiber carbohydrates (DNFC), that were obtained on Brazilian Scientific literature through in vivo experiments at maintenance level. The procedure to […]

Four buffaloes and four cattle, rumen fistulated, were utilized in two Latin Square (4 x 4) to evaluate the effects of rations with increasing levels of NDF (54, 60, 66 and 72% in DM) and two porous size of the nylon bags (53 and 100 mm) on the population of ciliate protozoa in rumen content and inside the nylon bags suspended in the rumen for several times. There was no difference in the several genus and in the total of […]

The experiment was carried out with the objective of determining the daily average intake (DAI) and apparent digestibility coefficient (ADC) of corn, sorghum and sunflower silages nutrients. The nitrogen balance was also evaluated. Nine castrated, male sheeps, kept in metabolism cages, in a 3 x 3 (three treatments and three periods), latin square design, were used. DAI of dry matter (DM), acid detergent fiber (ADF) and crude protein (CP) of corn silage of sunflower silage did not differ. DAI of […]

The knowledge of the anatomy of tropical forage grasses may help to improve its use as ruminant feed. The aim of this paper was to determine the area occupied by different tissues in stem and leaf in three cultivars of elephantgrass (Pennisetum purpureum Schumach.). Five plants of each cultivar were selected and segmented into three parts (apical, median and basal), this material being collected after ten weeks of regrowth. The stems were separated into two parts and the leaves segmented […]