The objective of this work was to evaluate the effects of density and feeding programs on the productive performance and carcass and prime cuts yield in broiler chickens at 42 days of age. A completely randomized design, in a 3×2 (density x feeding programs) factorial scheme, with three replications, was used. The densities were: 10, 12 and 16 birds/m2. The feeding was composed of program 1 (four diets): pre-initial, initial, growing and finishing and program 2 (five diets): pre-initial I, […]

Forty-eight female pigs were used to determine the commercial cut yields after slaughter of the animals at 50, 60, 70, 80, 90, 100, 110 and 120 kg and dissection of the carcasses. Life ultrasonic measures were taken to measure the longissimus muscle area and for backfat thickness. The predictors used to estimate the lean meat yield were backfat thickness and longissimus muscle area. Besides the measures made in the different cuts, as ham cut weight, ham muscle weight, palette muscle […]

Forty-eight female pigs slaughter at 50, 60, 70, 80, 90, 100, 110 and 120 kg were used to determine commercial cut and of lean meat yields in pork carcass, with a view of the Longissimus muscle area and backfat thickness estimation by using the real-time ultrasound technology. Live ultrasonic measurements were taken for Longissimus muscle area and for backfat thickness and measures in the hot carcass were made, using optical Henessy equipment, to estimate the backfat thickness and Longissimus muscle […]

Genealogies of 2070 animals and records from the first five lactations of 1406 cows of the Mantiqueira type cattle, daughters of 113 sires, were analyzed to estimate the frequency of inbred animals, the inbreeding average per generation and the possible effect of inbreeding increase on reproductive and productive traits. The evaluated traits were age at first calving (IPP), calving intervals (IDP), total milk production (PL) and lactation period (DL). Models for PL, IDP and DL included the fixed effects of […]

The objective of this work was to estimate the genetic parameters, product-moment and rank correlations between breeding values, and also correlated responses for reproductive traits using bivariate analysis of total milk production (PL) and the age at the first calving (IPP), or calving intervals (IDP), or days open (PSERV). Records from the NPZGJRA/IZ/APTA/SAA-SSP breeding program of the first five lactations of 1406 cows of Mantiqueira ecotype; daughters of 113 sires, with calvings from 1952 to 1997 were used. The MTDFREML […]

Weight records at 205 (205W), 365 (365W) and 550 (550W) days of age of three Nellore herds raised in Paraíba State from 1975 to 1990, were used in the analyses. Genetic and maternal effects were estimated with the restricted maximum likelihood method, assuming an animal model. There were included the fixed effects of year-month-sex and farm. The linear and quadratic effects of age of dam at calving were included in the model as covariables. The least squares means and respective […]

Weight data of 205 (205W), 365 (365W) and 550 (550W) days old of Guzerá herds raised on Paraíba State from 1975 to 1990 were analysed. Genetic and maternal effects were estimated by Restricted Maximum Likelihood method (REML). It was used an animal model with fixed effects of year-month-sex, farm and age of dam at calving (linear and quadratic). The general means for 205W, 365W and 550W were respectively 141.85 ± 28.67 kg, 199.08 ± 48.43 kg and 252.32 ± 64.90 […]

Variance components were estimated for the characteristic weights at 365 and 550-days of age of animals from genetic groups used on Canchim breed development. The objective was to verify the occurrence of heterogeneity variance among the genetic groups and the its possible effect during the ranking of animals, in the genetic evaluation. The estimates were obtained for the software MTDFREML. The strategy used to estimate the components of variance for both characteristics was to consider the expression of the characteristics […]

The knowledge of the genetic relationships between the parameters of lactation curve and the milk yield is important for the selection of cows and sire. The records milk yield from 583 cows of the Guzerá breed, daughters of 165 sire, were used to estimate the lactation curve parameters by two mathematical models. Milk productions were obtained from the extracted base of data from National Animal Science Archive maintained by National Center for Dairy Research (Embrapa Gado de Leite). The analyses […]

A good establishment is an important condition to obtain adequate levels of productivity in elephantgrass pastures. However, besides the adoption of good agronomic practices at planting, it is necessary to assure that the post-planting management is correct, to favor the future productivity and persistence of the pasture. Aiming at obtaining a good initial density of elephant-grass in the pastures, various post-planting management systems were studied. The following treatments were compared: grazing three months after planting, followed by cutting at 20 […]