Records from 14,918 Nellore animals born from 1991 to 2000 in 28 herds in the South and Southeast regions of Brazil were used to estimate (co)variance components and genetic parameters for weaning weight (WW), yearling weight (YW), weights at 18 month of age (WAY) and at first calving (WFC), age at first calving (AFC) and days to first calving (DC). Multivariate animal models were fitted by REML. Estimates of heritability for WW, YW, WAY, WFC, AFC and DC were 0.26; […]

The objectives of this study were to obtain heritability estimates for number (NBZ10 and NBZT) and kilograms (QBD10 and QBDT) of calves weaned up to ten years of age and during herd life, kilograms of calves weaned per year in herd (QTPR) and their genetic correlations with culling age, ages at first, at second and at third calving, adjusted and unadjusted weights for condition score, body size indexes and condition score at first mating, at first calving and at mature […]

The objectives of this study were to estimate heritability for culling age (TPR), ages at first (IDPP), at second (IDSP) and at third calving (IDTP) and genetic correlations of these traits with adjusted and unadjusted weights for condition score, body size indexes and condition score at first mating, at first calving and at mature age. Variance and covariance components were estimated by REML using univariate and bivariate models including the fixed effect of contemporary group and additive direct genetic and […]

This study aimed to evaluate the genotype × environment interaction effect on birth (PN), weaning (P205) and yearling (P550) weights of Nellore cattle raised in 46 farms in three states (Rio Grande do Sul-RS, Santa Catarina-SC and Paraná-PR) of the South Region of Brazil, from 1976 to 2001. Records on 10,874 animals, sired by 425 bulls and 7,629 dams were used to estimate (co)variance components by REML. Univariate and bivariate models included the contemporaneous group, feeding type (P205 and P550), […]

Data consisting of standardized weights at 120, 210, 365, 450 and 550 days of age (W120, W210, W365, W450 and W550), hip height at 18 months of age (HH) and standardized scrotal circumferences (SC) at 365, 450 and 550 days of age (SC365, SC450 and SC550) of Nelore animals born between 1998 and 2003, from ten ranches in six Brazilian States were used to estimate (co)variance components. Analyses were done by Restricted Maximum Likelihood methodology using single trait, two and […]

This study was carried out to identify, by using diagnostic research procedures, characteristics of production systems related to the occurrence of ectoparasites. Data of semi-structuralized interviews in 62 farms were analyzed by multivariate statistical procedures. Greater importance was observed for the property area, pasture management and the frequency of the property visits to his establishment. The used method, the season and the frequency of the applications of tick pesticides differed among the control types of ectoparasites. The results reaffirmed the […]

The aim of this work was to evaluate the effects of dry corn grain or high moisture corn and calcium salts of fat acids on the performance and carcass traits of feedlot fed Nellore steers on finishing phase. Forty eight animals with 431 ± 29.8kg of initial mean body weight were fed during 70 days, with one of the four diets: MGS – basal diet containing corn silage (40%), dry corn grain (48.4%), soybean meal (7.6%), urea, amonium sulphate, mineral […]

The productive and economic response of four feeding systems during the productive cycle of beef cattle raised and finished in tropical pastures was evaluated in this research. The data on supplement intake and performance of the animals were obtained from six experiments using 196 grazing animals. The evaluated supplementation strategies was based on the slaughter age of the animals (18, 24, 30, and 40 months), simulating a ideal system of production with area of 1.000 ha and annual average carrying […]

The objective was to evaluate the addition of additives in the ensiling of sugar cane (Saccharum officinarum L.) on the degradation of DM and components of cellular wall and on ruminal fermentation parameters in bovines fed with diets containing these silages. Five rumen-cannulated Nelore steers were allotted to a 5 x 5 latin square design. The steers were placed in metabolic cages and fed diets with 65% forage (%DM). Five silages were evaluated (wet basis): Control sugar cane, no additives; […]

The objective of this experiment was to study the development of external body components and that of discarded fat in feedlot finished crossbred cows from the second (G2 – 3/4Charolais (C) 1/4Nellore (N) and 3/4NC) and third (G3 – 5/8CN and 5/8NC) generations of a Charolais ´ Nellore rotational crossbreeding program slaughtered with 465 (T465), 507 (T507) and 566 kg (T566) of body weight. At the beginning of the trial, age, body weight and body condition score averaged, respectively, 8.5 […]