Ivo Francisco de Andrade

Parâmetros genéticos de longevidade e produtividade de fêmeas da raça Nelore

In order to estimate the (co)variance components, heritabilities and genetic correlations of longevity and herd life in females, informations of 56,413 births of females from a Nellore cattle herd, from 1950 to 2000, under different rearing and management conditions, were used. It was studied from calf: weaning weight (W205C), yearling weight (W365C), weight in 550 days (W550C), from cows: weaning weight (W205), yearling weight (W365) and weight in 550 days (W550), age at first calving (AFC), calving interval (CI), herd life (RL), longevity (LONG), reproductive efficiency (RE), index production (IP), index of metabolic production (IMP), sum of index production (SIP), sum of index metabolic production (SIMP). The analysis were performed using the MTDFREML software, estimating (co)variance components, assuming animal model. Direct genetic, maternal and permanent environmental effects were analyzed. Fixed effects of farm, feeding program, rearing condition, birth calf year, birth calf season and calf sex, were also analyzed. Heritability estimates showed similar results among the different analyses, higher (0.24 to 0.75) for W205, W365, W550, W205C, W365C, W550C, IP, IMP, AFC, RL, LONG and lower (0 to 0.10) for RE, CI, SIP and SIMP. Some correlations between maternal genetic effect and the growth traits were negative. In general, estimates of genetic and phenotypic correlations among LONG and growth traits were negative, suggesting genetic antagonism between LONG and early maturity, between the LONG and reproductive and productive traits were positive, suggesting the significant effect of reproductive and productive traits on LONG.

Características físico-químicas da carne de bubalinos e de bovinos castrados e inteiros

Meat physical and chemical characteristics of Nellore (NE) and F1 Nellore x Sindi (NS) cattle and Mediterranean buffaloes (BM) castrated and entire were evaluated. The experimental design was completely randomized in a factorial arrangement 3 (genetic groups) x 2 (sexual conditions) with 24 plots. Animals were confined, received the same diet and were slaughtered at average weight of 437.5 kg. Meat samples were taken from Longissimus dorsi muscle between 12th and 13th ribs. Castrated and entire animals meat obtained higher moisture (73.6 vs 71.0%), protein (87.5 vs 78.6%), ash (4.33 vs 3.85%) and smaller fat (8.9 vs 16.8%) content. NE cattle meat showed higher fat content (15.4%) than NS cattle (12.5%) and BM (10.8%), but no difference of sexual condition was observed in BM group. Meat and fat luminosity, red intensity and yellow intensity were similar among NE, NS and BM, while castrated reached higher luminosity (39.0 vs 37.2) and yellow intensity (1.82 vs 0.87) than entire, but meat red intensity and fat luminosity, red intensity and yellow intensity were similar among genetic groups and between sexual condition. BM meat showed smaller shearing force (3.75 kgf) than NS (4.85 kgf) e NE (5.9 kgf), as well as castrated (4.5 kgf) in relation to entire (5.2 kgf), but no difference was observed among genetic groups and sexual condition from cooking weight loss and final pH. Buffaloes meat and entire animals showed smaller fat content, maintaining the nutritive value and tenderness and decreasing cooking weight loss.

Rendimentos do abate e carcaça de bovinos e bubalinos castrados e inteiros

ABSTRACT - It was slaughtered 24 animals confined, being 8 (4 castrated and 4 entire) from each genetic group (Nelore, ½ Nelore x Sindi cattleand e Mediterrâneos buffaloes), with 430 kg mean weight, in order to compare carcass and slaughter yield. Data obtained were analyzed statisticallyin a factorial scheme 3 x 2 (3 genetic groups x 2 sexual conditions) with 4 repetitions. Nelore and ½ Nelore x Sindi cattle presented smaller percentageof foot (2 .13, 2 .08 vs 2,31%), head (3 .99, 4 .48 vs 5 .04%), hide (7 .45, 8 .21 vs 9 .92%) and viscera (25,6; 25,1 vs 28,4%) than buffaloes, but no differencewas observed for foot and viscera percentage among castrated and entire animals. Castrated animals presented hide with smaller percentage than entire(8.20 vs 8.85%), similar head percentage, being the tail percentage was higher in castrated animals (0 .29 vs 0 .26%). Carcasses of Nelore and ½ Nelorex Sindi cattle reached higher yield (58 .7 and 58.1 vs 52.3%) than buffaloes, while castrated and entire dressing percentage was similar. Carcass andslaughter yield in relation of slaughter weight were higher on Nelore and ½ Nelore x Sindi cattle than buffaloes: carcass (60.6 and 59.9 vs 54,1%),hindquarter (27 .98 and 27 .1 vs 25.6%), forequarter (24 .8 and 24 .9 vs 20.3%) and similar side cut (7 .82 and 7.83 vs 8.23%), while entire presentedhigher forequarter (23 .9 vs 22,8%) than castrated. For carcass yield and their cuts in relation of carcass weight, Nelore and Nelore x Sindi cattle attainedsmaller hindquarter cut percentage than buffaloes (46 .7, 45 .9 vs 47 .8%), while the castrated animals attained higher hindquarter percentage than entire(47.3 vs 46.3%). Nelore and Nelore x Sindi cattle obtained higher forequarter cut percentage (40 .7, 41.4 vs 37.4%) than buffaloes, as well as entireanimals (40.7 vs 38,9%) in relation to castrated. Nelore and ½ Nelore x Sindi cattle presented smaller side cut percentage (12 .9 and 13.1 vs 15.2%)than buffaloes. For carcass cuts chilling loss there was no difference among genetics groups and sexual conditions. It was concluded that differencesamong cattle and buffaloes are independent of sexual condition and that buffaloes present smaller carcass yield because their higher proportion of foot,head, hide and viscera, though they present higher hindquarter proportion in function of carcass weight.Key Words: buffalo, cattle, carcass, castrated, entire

Estabelecimento de pastagem de capim-tanzânia usando milheto como cultura acompanhante

The objective was to evaluate the forage yield and chemical composition of millet and Tanzania grass, the first one as a companion crop, in the formation of the Panicum maximum Jacq. cv. Tanzania I pasture, as well as the viability of the use of this practice. The evaluated treatments were four seed mixture combinations based on sowing density of 8 kg/ha of Tanzania grass/millet (08/00; 05/03; 04/04 and 03/05 kg/ha) and three cutting frequencies (three cuttings - 40, 70 and 100 days after sowing), two cuttings - 50 and 100 days after sowing; one cutting ¾ 100 days after sowing), in a randomized complete block design with four replications assigned to a split-plot arrangement. The sowing densities were allocated in the main plots and cutting frequencies, in the subplots. The DM yields of the association millet with Tanzania grass were higher than that for pure Tanzania grass stand. The CP increased whereas NDF and ADF decreased in both millet and Tanzania grass with the increasing cutting frequency. However, in the combination, similar values were observed in the content of this variables and a small reduction in CP content when compared to Tanzania grass stand. According to these results, it was concluded that its feasible the establishment of Tanzania grass pasture using millet as a companion crop.

Estrutura do pasto disponível e do resíduo pós-pastejo em pastagens de capim-cameroon e capim-marandu

Two experiments were carried out to evaluate structural characteristics and crude protein concentration of Pennisetum purpureum cv. Cameroon and Brachiaria brizantha cv. Marandu under four rotational stocking rates. During the rainfall period, the studied stocking rates for both pastures were 3, 4, 5, and 6 steers/ha and in the dry period the stocking rates were 2, 3, 4, and 5 steers/ha. In both experiments, elephantgrass cv. Cameroon produced greater total herbage mass and green herbage mass, which decreased with the increase in defoliation as a result of the used stocking rates, mainly during the dry period. For elephantgrass pastures, the increase in stocking rate had a greater negative effect on the green leaf blade dry matter fraction. In the rainfall period, the stocking rates which promoted greater herbage allowance, green herbage mass, and leaf blade fraction were 5 steers/ha and 4 steers/ha for elephantgrass cv. Cameroon and marandugrass, respectively. In the dry period, greater values for these variables were obtained with 4 steers/ha and 3 steers/ha, respectively. Stocking rates did not influence crude protein concentration of the grasses, with leaf blade presenting higher concentration of this nutrient.

Dinâmica de perfilhamento e fluxo de biomassa em capim-cameroon sob lotação rotativa

The population dynamics of tillers and tissue turnover were investigated in pastures of Pennisetum purpureum Schum. cv. Cameroon submitted to different stocking rates under rotational stocking. Two experiments were carried out and the experimental area was characterized by a mean annual rainfall of 1,311 mm and average temperature of 25oC. In the rainfall period the stocking rates were 3, 4, 5, and 6 steers/ha; in the dry period the stocking rates were 2, 3, 4, and 5 steers/ha. The most intensive grazing lead to the greatest number of basal tillers, with values ranging from 59.02 to 57.75 and 64.64 to 81.36 tillers/m2 for the stocking rates of 5 to 6 and 4 to 5 steers/ha in the rainfall and dry periods, respectively. Considering the aerial tillers, cameroon grass showed 350.83 and 278.05 tillers/m2 for the stocking rates of 5 to 6 steers/ha, in the period of rainfall. In the dry period, the stocking rate of 4 steers/ha lead to 399.20 aerial tillers/m2. Increasing stocking rates reduced the daily stem elongation. Leaf appearance rate (TApF) and leaf elongation rate (TAIF) did not differ among stocking rates neither differed between experiments; TapF ranged from 0.10 and 0.13 live leaves/day and TAIF ranged from 0.82 and 1.36 cm/leaf/day. The average number of live leaves/tiller was 8.04 and 9.51 for the rainfall and dry period, respectively, decreasing with increasing stocking rate.

Condição corporal e características de carcaça de vacas de descarte na região de Lavras-MG

Em inumeras pesquisas, tem sido verificada a inferioridade da carcaca e da carne de vacas, principalmente de vacas de descarte que sao levadas ao abate muito velhas e/ou com acabamento inadequado. Com este trabalho, teve-se como objetivos estabelecer entre as vacas abatidas no municipio de Lavras-MG a condicao corporal mais frequente durante o periodo de marco a julho e avaliar a relacao existente entre condicao corporal e rendimento de carcaca e de alguns cortes do traseiro. O levantamento foi conduzido no matadouro municipal de Lavras-MG e dividido em duas fases assim compreendidas: Fase 1 (1o a 31 de marco de 2001), na qual se determinou que 53,41% do total de animais abatidos no periodo foram femeas e que os escores de condicoes corporais (ECC) mais frequentes entre elas foram 3, 4 e 5. Na fase 2 (15 abril a 15 de julho de 2001), foram utilizadas 140 femeas, 42 vacas da CC 3, 59 femeas da CC 4 e 39 da CC 5. Em cada escore, as vacas foram classificadas em tres grupos geneticos: azebuadas, holandesadas e mesticas. No matadouro, antes do abate, as vacas foram pesadas, classificadas quanto a condicao corporal e grupo genetico e fotografadas para posterior classificacao por outros avaliadores. Os parâmetros avaliados foram: rendimento de carcaca quente (RCQ), peso da gordura renal e pelvica, area de olho de lombo (AOL), espessura de gordura de cobertura (EGC) e pesos dos cortes (contrafile, alcatra completa e file mignon). O escore de condicao corporal (ECC) teve influencia sobre o RCQ, a EGC, o peso da gordura renal e pelvica e o peso da alcatra completa nos tres grupos geneticos. Para a AOL e o peso do file mignon, so foi observado efeito do ECC sobre as vacas azebuadas; o peso de contrafile nao foi afetado pelo ECC. As vacas azebuadas apresentaram maior RCQ e EGC; porem, a maior AOL foi observada entre as vacas holandesadas. A gordura renal e pelvica e o peso dos cortes (alcatra, contrafile e file mignon) nao variaram entre os grupos geneticos. Pelos resultados obtidos, pode-se concluir que as vacas abatidas no periodo apresentaram baixa condicao corporal e que essa influencia as caracteristicas de rendimento na carcaca.

Características de carcaça e cortes comerciais de tourinhos Red Norte suplementados com óleos de fritura e soja terminados em confinamento

The objective of this study was to evaluate the characteristic of carcass and commercial meat cuts from Red Norte young bulls finished in feedlot supplemented with fry and soybeans oil. Twenty seven Red Norte animals at initial average weight of 317 ± 33kg were used. The animals received ad libitum feed with concentrate:roughage ratio of 40:60, being: control diet; supplementation with soybeans oil and supplementation with fry oil, during 112 days, from which 28 days were for adaptation, and slaughtered with 481,0; 488,7 e 462,6kg to treatments control, supplemented with soybeans oil and with fry oil respectively. The subcutaneous fat thickness (FT) and longissimus muscle area (LMA) were measured between the 12th e 13th ribs. The supplementation with lipids sources did not influence the final weight, hot carcass weight, cold carcass weight, LMA, FT, losses by cooling, weight and yield of the forequarter, hindquarter and spare ribs cuts. However the carcass dressing was lower to animals supplemented with soybeans oil. The final pH was higher (P<0,01) to carcasses of the animals supplemented with fry oil, and the final temperature (P<0,02) was higher to animals supplemented with lipids than to animals without supplementation. The lipid supplementation used to young bulls in feedlot did not influence the carcass characteristics. However, animals supplemented with fry oil presented DFD meat, whereas animals supplemented with soybeans oil had lower dressing carcass.

Níveis e frequência de suplementação de novilhos de corte a pasto na estação seca

The objective of this study was evaluate the levels of protein-energy supplementation, offered at different frequencies, to growing steers kept on Brachiaria decumbens pasture during the dry season. Twenty-five no castrated steers were used, 191 kg initial average weight, in a randomized complete block design, with five replications per treatment in a 2 × 2 + 1 factorial arrangement, that is, two protein-energy supplementation levels (0.3 and 0.6% on the basis of body weight (BW)), two supplement distribution frequencies - daily or on alternate days, plus an additional treatment (only mineral supplementation). Forage dry matter intake (FDMI) was estimated using two markers, chromic oxide and indigestible dry matter (DMi). The dry matter intake of the supplement was measured daily because the supplement was offered to each steer individually. The supplementation increased dry matter intake and the average daily gain (ADG) (1.66% of BW and 290 g/day), compared to the additional supplement (1.49% of BW and -107 g/day). The herbage dry matter and neutral detergent fiber intake were greater animals supplemented only with mineral mixture (1.48 and 1.1% BW), and smaller for the supplemented ones (1.27 and 0.95% of BW), respectively. Forage intake reduction did not differ among the supplemented levels (299 g/day). The supplementation with 0.6% BW presented a better average daily gain than the 0.3% BW (343 versus 238 g/day), but it was 39% less efficient at converting the supplement into live weight gain. There was no effect of frequency on the variables studied. Supplementation on alternate days seems to be an interesting alternative for cattle feeding, regardless of the amount of supplement offered.

Characterization of cattle slaughtered at the public abattoir in Lavras-MG

The objective was to characterize cattle slaughtered from the region of Lavras - MG. In the public abattoir 720 bovines were identified and slaughtered from September 20th through November 20th of 2004. Variables such as: genetic origin, live weight, body condition, age, and sex were studied. At arrival, animals were weighed and classified according to their genetic origin. Before slaughter, their body condition (BC) was determined on a 1 - 9 scale. Reproductive status was observed during scratch and evisceration: castrated male, MC; intact male, MI; pregnant female, FG; and Non-pregnant female, FNG. Age was determined by the count of the permanent incisive teeth (p.i.t.). Most animals slaughtered during the survey were male, with predominance of the Girolando genetic group. Overall mean slaughter weight was 438.5 ± 115.97 Kg (n=720). Females (FG and FNG) were older (>48 months old) as compared to male animals, FNG had lower body condition scores (3, 4 and 5). Male (MC and MI), had good body condition scores. Most of slaughtered cattle in Lavras were characterized as non-specialized for beef production.