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 determine the macrominerals requirements (Ca, P, Mg, Na, and K) for young bulls from different genetic groups. Forty-four young bulls from the following genetic groups were used: Nellore, F1 Nellore x Aberdeen-Angus, F1 Nellore x Brown Swiss, and F1 Nellore x Simmental. Animals averaged 362 ± 35 kg of initial body weight and between 10 to 11 months of age. Diet contained signal grass hay (Brachiaria decumbens, Stapf.), soybean meal, ground corn, molasses, […]

A trial was conduced to evaluate decreasing levels of CP with amino acid supplementation on performance of gilts on thermoneutral environment. Thirty-five crossbreed gilts (Landrace x Large White) averaging initial weight of 60.5 kg were allotted to a complete randomized design with five treatments (17.3, 16, 14.7, 13.4 and 12.1% of CP) of seven replications (one animal per experimental unit). The experimental diets were fed ad libitum until the end of the experiment when the animals reached the average weight […]

A static, empirical and determinist model of ingestion, retention and excretion of N and P was developed for the Brazilian pig production. The general principles were: technological systems (ST), animal categories, N and P in the diets, and digestive and metabolic efficiencies of N and P. The model integrates three aggregation levels, being constituted by ten compartments (ingestion, gastrointestinal contents, retention, and excretions of P and N), 300 sub-compartments (50 related to ST and 250 to animal categories). The ST […]

An study was conducted to evaluate the influence of reduction of crude protein (CP) levels and amino acid supplementation in diets on the performance of castrated swines (Landracex Large White) maintained in a termoneutral environment. Fifty crossbreed piglets (average initial body weight of 30.2 kg) were allotted to a completely randomized experimental design with five treatments (17, 16, 15, 14 and 13% CP) and five replications and two animals per experimental unit. Experimental diets and water were fed ad libitum […]

Fifty-six pigs (average initial weight of 28.47 kg) were assigned to a randomized blocks design, in a factorial scheme 4 x 2 (levels of dicalcium phosphate substitution x sex) with four repplicates for males and three for females, with two animals per experimental unit, to evaluate the effects of replacement levels of phosphate dicalcium by phosphate monodicalcium on the performance, blood and bone parameters of swine fed during the growing (30 to 60 kg) and finishing (60 to 90 kg) […]

The domestication of Podocnemis expansa (Gigant Amazonian turtle) with commercial purpose it was implanted in Brazil in 1992. However, a lot of subjects about handling, nutrition, sanity and mainly reproduction are still obscure these animals. The objective of this study was evaluated the effects of crude protein concentration and source on body weight of Podocnemis expansa. The turtles (n=480) were transferred to Setor de Piscicultura EV/UFG. Six animal groups (80/each) were put in water tanks of 500 liters. Five groups […]

Two experiments were carried out aiming to compare techniques of digestibility of fish food nutrients, by using external indicators (chromic oxide and barium carbonate), internal indicators (HCl-insoluble ash, acid detergent insoluble ash, crude fiber and acid detergent fiber) and the direct determination technique. Corn meal was used in the first experiment and soybean meal was used in the second one; both used 100 g tambaquis. Chromic oxide and barium carbonate are effective external indicators for estimating the digestibility coefficients of […]

Twenty-eight male pigs averaging 28.95 kg were used to determine endogenous fecal losses, true absorption and phosphorus bioavailability in different phosphorus sources. The experiment was arranged in randomized blocks, with seven treatments and four repplicates and one pig/box. The diets were corn and soybean meal-based and the phosphorus (P) was supplemented through different phosphate sources: dicalcium (FBC), monodicalcium (MBC), triple superphosphate (ST), simple superphosphate (SS), Catalão rock (ROCHA) and phosphoric acid (AcF) and diet control without supplemental P (CONT). Phosphorus […]

Three assays were carried out to determine methionine + cystine requirement and the digestible methionine + cystine: digestible lysine ratio of males broilers, Avian Farms, from 1 to 20, 24 to 38 and 44 to 56 days of age. Each experiment was a completely randomized design with five levels of methionine + cystine, six replications and 20 birds per pen from 1 to 20 and 24 to 38 and 16 birds per pen from 44 to 56 day of age, […]