D.S. Graça

Desempenho e consumo de matéria seca de bovinos sob suplementação protéico-energética, durante a época de transição água-seca

The effect of two levels of daily intake (0.17% and 0.37% of live weight) of protein and energy supplementation on weight gain and on dry matter intake of bulls grazing Brachiaria Brizantha cv. Marandu grass was evaluated. Forty two bulls (Holstein x Gir - HG), averaging 211kg initial LW, were used in the performance trial, and 15 HG steers, averaging 239kg initial LW, for evaluation of total dry matter intake (TDMI) and forage dry matter intake (FDMI). The treatments were: MS - mineral supplementation, SUP1 - protein and energy supplementation with an average daily intake of 0.17% of the live body weight, and SUP2 - protein and energy supplementation with an average daily intake of 0.37% of the live body weight. The average FDMI intakes were 2.6, 2.4, and 2.3% of the LW, for MS, SUP1 and SUP2, respectively. The average TDMI intakes were 2.6, 2.6, and 2.6% for MS, SUP1, and SUP2, respectively. Protein and energy supplementation increased weight gain from 0.54kg/day in the MS treatment to 0.66 and 0.75kg/day for SUP1 and SUP2, respectively.

Produtividade e eficiência econômica de sistemas de produção de cria, recria e engorda de bovinos de corte na região sul do estado da Bahia

Economic efficiency and productivity of life-cycle cattle raising systems were studied by simulations that differed in calving rates (CR). The study was conducted on a life-cycle cattle production system (SCC) with 87% CR, and three simulated systems: -4CR with 83% CR, -2CR with 85% CR, and +2CR with 89% CR. The SCC was based on data from a life-cycle cattle system of 3,453 animals in the South of Bahia State, from January 2000 to December 2002. CR was adjusted according to energy requirement and herd composition in SCC during three years. Meat amount sold was 149, 146, 144, and 141kg/ha/year for -4CR, -2CR, SCC, and +2CR, respectively. Accumulated profit and return on invested capital were R

Uso do óxido crômico e do LIPE® na estimativa do consumo de matéria seca por bezerros de corte

780,695.42 and 7.8%; R

Suplementação com cromo e desempenho reprodutivo de vacas zebu primíparas mantidas a pasto

737,526.16 and 7.4%; R

Análise econômica da suplementação protéico-energética de novilhos durante o período de transição entre água-seca

727,031.52 and 7.3%; and R

Cinética de degradação e fermentação ruminal da Brachiaria brizantha cv. marandu colhida em diferentes idades ao corte

703,907.58 and 7.0% for -4CR, -2CR, SCC, and +2CR, respectively. Calving rate variation modified the economic efficiency and productivity of simulated production systems. Economic efficiency and productivity results decreased as calving rate increased.

Efeito do níquel e da concentração protéica sobre o consumo e digestibilidade aparente da materia seca, proteína bruta, energia e balanço de nitrogênio do feno de Brachiaria brizantha cv. Marandu em ovinos

Six male and six female calves, seven-month-old, averaging 168kg bw, grazing on Brachiaria decumbens, were used in a split plot design to compare the efficacy of two external markers: chromic oxide (Cr2O3) and purified and enriched lignin (LIPE®) simultaneously dosed once a day to predict dry matter intake (DMI). For both, Cr2O3 and LIPE®, no differences in DMI according to gender were observed. Comparing the efficacy of the two markers to predict fecal output and pasture intake, the estimates obtained with chromic oxide were lower. Forage DMI, total DMI, DMI as percentage of body weight, and DMI in relation to metabolic weight were: 2.03 and 4.50kg; 2.71 and 5.18kg; 1.62 and 3.10%, and 58.10 and 111.32g/kg bw0.75 for Cr2O3 and LIPE®, respectively. These results suggest that estimates obtained from LIPE® were more appropriate to the dry matter requirements and performance of the calves.

Suplementação de novilhos Nelore sob pastejo, no período de transição águas-seca

One hundred and twenty six grazing primiparous Zebu cows were assigned to one of two treatments, supplemental chromium (Cr) (72 cows) and control (54 cows), in order to evaluate the effects of Cr supplementation on reproductive performance of cows. Chromium was supplemented as high-Cr yeast Sacharomices cerevisae added to mineral premix (0.017% Cr). Chromium had no effect on calf weight, whereas final weight of cows was higher for the supplemented group (428.5kg vs. 380.5kg).The percentage of detected estrus was higher for Cr supplemented group than for control group (98.6 vs. 88.7%) A tendency for higher pregnancy rate was showed by the Cr supplemented group (87.5% vs. 75.47%). The calving - first estrus interval of the Cr supplemented cows was lower than control cows (120.5 vs. 142.8 days). Supplementation of chromium had neither effect on service rate (1.57 vs. 1.69 doses of semen) nor on pregnancy (1.85 vs. 1.90 doses of semen).

Comparação de métodos "in vitro" para determinação da biodisponibilidade de fósforo

The effects of protein and energy supplements at two levels of daily intake - 0.17% and 0.37% of live weight (LW) - on the performance of steers under Brachiaria brizantha cv. Marandu pasture were economically evaluated using 14 steers per treatment. Treatments were: MS - mineral supplementation (control), SUP1 - protein and energy supplementation with an average daily intake of 0.17% of live weight, and SUP2 - protein and energy supplementation with an average daily intake of 0.37% of live weight. Steers of treatments SUP1 and SUP2 showed higher weight gains, 0.655 and 0.746kg/animal/day, respectively, in relation to those in the control group, 0.535kg/animal/dia. Higher operational profits were observed, R

Influência da aplicação de gesso na produção de matéria seca, na relação nitrogênio: enxofre e concentrações de enxofre, cobre, nitrogênio e nitrato em pastagens de Brachiaria decumbens Stapf

67.12/animal/period and R