The work was carried out to evaluate the microbial protein production determination by means of the urinary excretion of purine derivatives; to compare the microbial protein production by means of purine base methods and of the urinary excretion of purine derivatives; to determine the microbial protein production on the dry matter intake and percentage of neutral detergent fiber in the diet; and to establish the allantoin: uric acid ratio, in relation to the xanthine and hypoxanthine in the urine. Five […]

The experiment was carried out to evaluate the effect of the use of whole fermented soybean (WFS), whole extruded soybean (WES) and soybean meal (SBM) in replacement to the dried milk (MD) of the diet on the performance, feed intake and morphological alterations on the digestive system of piglets from 14 to 35 day and from 14 to 56 days, and its residual effects from 36 to 56 days of age. Ninety-six crossbreed (Landrace x Large White) piglets weaned at […]

The objective of this work was to determine, through a digestibility assay, the nutritional requirement of true digestible lysine for broiler chickens, in the four growing phases. Four performance experiments, previously performed, allowed the determination of total lysine requirement of broiler chickens in the periods from 1 to 21, 15 to 40, 22 to 40 and 42 to 48 days of age. Thirty cecectomized adults Leghorn roosters were used, with an average weight of 2316±190 g, and individually caged in […]

Two experiments were conducted to study the effects of (Na + K)/Cl ratio on the diet of commercial laying hens, at the end of egg production by the addition of sodium bicarbonate (NaHCO3), sodium chloride (NaCl), potassium chloride (KCl) and ammonium chloride (NH4Cl), with regard to productive parameters and plasma blood characteristics. The first experiment involved five treatments: 0.30% NaCl; 0.30% NaCl + 0.95% NaHCO3; 0.38% KCl + 0.67% NaHCO3; 0.8% KCl + 1.62% NaHCO3 and 0.38% KCl + 2.56% […]

A field plot experiment was conducted, in a split plot design with 12 replications to compare the percentages of crude protein (CP), neutral detergent fibber (NDF) and in vitro dry matter disappearance (IVDMD), of the whole plant and its leaf blades and stems of the grasses Marandu (Brachiaria brizantha Stapf. cv. Marandu), Setaria (Setaria sphacelata cv. Kazungula ) and Tanzania (Panicum maximum Jacq. cv. Tanzania-1) in cuts taken at 35 days of growth in the spring (11/21 to 12/25/97), summer […]

Two experiments were carried out to determine the sodium (Na+) and chloride (Cl–) requirements for broilers in the pre-initial phase (1 to 7 days of age) and the best electrolyte balance of the diet. In each experiment 1500 broilers from Cobb strain were allotted to a completely randonmized design with six treatments, five replicates and 50 birds per experimental unit. The treatments used in the two experiments consisted of diets with levels on 0.10, 0.15, 0.20, 0.25, 0.30 and 0.35% […]

The work was carried out to evaluate the plasma N-urea concentration (NUP), the urea fractional excretion (UFE) and the creatinine (CE) and urea (EU) excretions for several experimental conditions; to establish the relation among NUP, the urea fractional excretion and the urea excretion with the dietary crude protein (CP) and NDF percentage; and to evaluate the urinary endogenous losses, by means of the creatinine excretion determination. In the experiments I and II, diets with 25.0, 37.5, 50.0, 62.5, and 75.0% […]

Informations of 7986 births of animals from a Nellore cattle herd, from 1960 to 1993, were used to estimate (co) variance components, heritabilities and genetic correlations of weaning weight (W240), yearling weight (W365), age at first calving (AFC), first calving interval (CI1), reproductive efficiency (RE), longevity (LONG), calculated as years of permanence of cow in herd and weaning weight of the first calf of cow (W240C). The analysis were performed using the MTDFREML software, estimating the (co) variance components by […]

This experiment was conducted to study the effect of the inclusion of a commercial enzyme complex (alpha-amylase, xylanase and proteases) especific for corn and soybean meal based diets, on laying hens performance. One hundred and twenty eight Hy-line White Leghorns hens with 68 weeks of age, in the 2nd cycle of production were assigned to a completely randomized block design with four replications of four birds per block, totalizing 32 birds per treatment. Two isonitrogenous diets with different levels of […]

An equation based on heat transfer theory was presented to estimate the rate of heat loss from cattle exposed to a tropical environment, specified by the air temperature, humidity, solar radiation, and wind speed. The animals’ variables (sweating rate, rectal temperature, respiratory rate, surface temperature, haircoat color, and body weight) were considered together with environmental variables (air temperature and humidity, solar radiation, wind speed, and globe temperature). The equation allows the prediction of (a) the metabolic heat production level necessary […]