The Revista Brasileira de Zootecnia (RBZ) is a publication dedicated to the broad field of Animal Science. We publish high-quality, original scientific research that spans across diverse areas within the discipline. The scope of RBZ encompasses a wide range of topics, including aquaculture, biometeorology and animal welfare, forage crops and grasslands, animal and forage plants breeding and genetics, animal reproduction, ruminant and non-ruminant nutrition, meat science and muscle biology, precision livestock, and animal production systems and agribusiness.
The Revista Brasileira de Zootecnia (RBZ) is a publication dedicated to the broad field of Animal Science. We publish high-quality, original scientific research that spans across diverse areas within the discipline. The scope of RBZ encompasses a wide range of topics, including aquaculture, biometeorology and animal welfare, forage crops and grasslands, animal and forage plants breeding and genetics, animal reproduction, ruminant and non-ruminant nutrition, meat science and muscle biology, precision livestock, and animal production systems and agribusiness.
The Revista Brasileira de Zootecnia (RBZ) is a publication dedicated to the broad field of Animal Science. We publish high-quality, original scientific research that spans across diverse areas within the discipline. The scope of RBZ encompasses a wide range of topics, including aquaculture, biometeorology and animal welfare, forage crops and grasslands, animal and forage plants breeding and genetics, animal reproduction, ruminant and non-ruminant nutrition, meat science and muscle biology, precision livestock, and animal production systems and agribusiness.
A digestibility assay were carried out to evaluate, in consecutives periods, the total excreta collection method and the chromium oxide method as a marker. Apparent metabolizable energy corrected by nitrogen retention (AMEn) and aparent digestibility of dry matter coefficient (ADDMC) of broiler diet based in a ground corn and soybean meal containing 19% crude protein and 3.100 kcal ME/kg. Sixty adult Leghorn cockerels weigh, in average, 2.350±105 g were used. Each cockerel participates in the evaluation of the two methods […]
An experiment was carried out at Universidade Federal de Viçosa to determine the metabolizable energy values of different samples of feather meal and poultry by-product meal with different levels of inclusion and at different poultry ages. The ten treatments used to determine energy consisted of a reference diet and ten test diets, obtained with the replacement of reference diet by five levels (5, 10, 20, 30 and 40%) of feedstuffs. The metabolism trials (total fecal collection) were carried out in […]
The study aimed to evaluate the performance and carcass yield of four quail genetic groups male and females. The birds were grown until 42 days old. A thousand and two hundred day old quails were distributed in a completely randomized design with four treatments (A, B, C and D) and five replicates of 60 birds each. The birds were weighed once a week in order to evaluate weight gain and feed consumption. Mortalities were recorded daily. At 42 days, ten […]
The study aimed to evaluate the performance and egg quality of four genetic groups selected for meat production. Two hundred and eighty eight quails 42 days old were used. The experiment design was the completely randomized blocks with four treatments (genetic groups A, B, C and D) and six replicates of 12 birds each. In the first week, it was given 14 hours of light with increases of 30 minutes per week until it reached 17 hours of light. Egg […]
With the objective to evaluate the effect of feed restriction on fecal mineral content of finishing swine, forty-eight barrows, with initial weight of 41.92 ± 0.27 kg were assigned to a randomized experimental block design. Treatments were: T1=ad libitum feeding; T2=95% T1 feed intake; and T3 = 90% T1 feed intake and 16 replications. Animals were kept during 21 days in adaptation period to the treatments in collective pens and metabolism cages. Urine and fecal collection was performed during two […]
Fifty barrows from 29.97 ± 0.36 kg to 60.38 ± 0.49 kg were used to evaluate the requirement of digestible methionine + cystine. A completely randomized blocks design, with five digestible methionine + cystine levels (0.448; 0.490; 0.531; 0.573 and 0.614%), with five replicates and two animals per experimental unity, was used. The digestible methionine + cystine levels of the diet influenced in a quadratic way the average daily gain and the feed:gain being the level of digestible methionine + […]
This work was developed to evaluate the effect of different levels of crude protein (CP) and metabolizable energy (ME) on the performance of laying quails. Six hundred and seventy tywo Japanese quails (Coturnix coturnix japonica) from 42 days to 168 days of age were divided in six periods of 28 days each. The birds were assigned to a completely randomized design, with the treatments in a factorial arrangement of 4 x 4 (protein x energy), with six replication of seven […]
The aims of this research were to determine economic selection indices in order to reach the target objective for a Caracu cattle nucleus. The breeding objective (H) considered a dual purpose breed producing milk and weaning calves. The biological traits affecting income and expenses considered in H were: total milk yield, age at first calving, number of days open, weaning weight, and productive lifetime. Two economic selection indices were calculated. The selection criteria included in Index 1 were first lactation […]
Two different preweaning selection criteria in Gyr cattle: average daily gain from birth to weaning (ADG) and number of days to gain 160 kg from birth to weaning (D160) were evaluated in this study. Records from the Brazilian Zebu Breeders Association obtained from 1978 to 1994, were studied. (Co)variance components and heritabilities were estimated by restricted maximum likelihood derivative free method, and expected breeding values (EBV) were predicted using an single trait animal model. In the model, contemporary group was […]
A data set with 16,592 records from the Brazilian Zebu Breeders Association obtained from 1978 to 1994, was used to estimate genetic parameters for preweaning average daily gain (ADG) and number of days to gain 160 kg (D160) in Gyr cattle. The (co)variance components and heritabilities were estimated by the restricted maximum likelihood derivative free method. Two models were used: the first one considered contemporary group (CG) as fixed effect and additive direct and maternal genetic effects, maternal permanent environment […]