Data from the Caracu herd of Sertãozinho Experimental Station, selected for post weaning weight between 1979 and 2002, was analyzed to describe effective size, generation coefficient, generation interval, selection differentials and genetic gain in this population. Genetic gain was estimated by the product of the average weighted standardized differential (kg) and heritability divided by the average generation interval. Averages of sire and dam weighted selection differentials for post weaning weights were 1.10 and 0.28 standard deviations units (s.d.u). Sire and […]

The objetive of this study was to evaluate the performance of broiler genotypes using repeated measurements. Four genotypes (A, B, C, and D) and two sexes were evaluated at six ages (7, 14, 21, 28, 35, and 42 days) for average feed intake (AFI), average body weight (ABW) and feed:gain ratio (F/G) using an unbalanced incomplete blocks 4×2 factorial design. Five error co(variance) structures were tested using the MIXED procedure of SAS® for statistical analyses. Averages were estimated by least […]

Weight records of 24.028 zebu animals from Guzerá, Nelore, and Polled Nelore breeds available from Brazilian Association of Zebu Breeders (ABCZ) database were used to estimate growth curve parameters. The measures were taken on animals which were born between 1960 and 2000, every three months, from birth to 24 months of age. Non-linear Brody, Gompertz, Logistic, Mitscherlich, von Bertalanffy, Richards, and Double Logistic models including sex, farm, year of birth, month of birth, raising system, and interaction sex*raising system as […]

Weight records of 24.028 zebu animals from Guzerá, Nelore, and Polled Nelore breeds available from Brazilian Association of Zebu Breeders (ABCZ) database were used to estimate heritabilities of growth curve parameters. Non-linear Brody, Gompertz, Logistic, Mitscherlich, von Bertalanffy, Richards, and Double Logistic models including sex, farm, year of birth, month of birth, raising system, and interaction sex*raising system as fixed effects and sire and dam, as random effects were adjusted using weight-age records of animals which were born between 1960 […]

Random regression models using Legendre polynomials were used to describe the growth curve of Nelore cattle weighted every three months from birth to 720 days of age, in Pernambuco state, northeastern Brazil. Six different random regression models using Legendre polynomials of three, four, and five degrees to model additive genetic and permanent environmental effects, under homogeneous and heterogeneous residual variances with three classes were evaluated. According to the Akaike’s information criteria, the five degree Legendre polynomial with homogeneous error was […]

One experiment was carried out to determine the lysine (Lys) and metabolyzable energy (ME) levels for breeding gilts. One hundred and eight Seghers® gilts (Large-White x Landrace/Large-White) were alloted to a complete randomized design with a 3×3 factorial design, three levels of Lys (0.55, 0.75 and 0.95%) and three levels of ME (3,100, 3,250, and 3,400 kcal ME/kg). The treatments were the same from the beginning of trial (housing) to the slaughter (30 days of gestation). There was only effect […]

Four hundred and eighty broilers were assigned to a completely randomized design with a 6×2 arrangement (six levels of manganese and 2 sexes – male and female) and four replicates to determine the manganese requirements in the growing (22 to 42 days) and finishing (43 to 54 days) phases. Six and four birds per experimental unit, respectively, were used in the first and second trials. In both trials, the treatments consisted of a basal diet deficient in manganese (6.5 ppm) […]

The objectives of this trial were to evaluate the efficacy of oregan extract (OE), as growth promoter, in the diets, on performance, immune system (bursa Fabricius weight and volume, spleen weight and thymus weight), anatomic-physiological parameters of the gastrointestinal tract (villy height, crypta depth and villy:crypta ratio), caecum microbiological analysis, and duodenum and caecum pH. One thousand and fourty male Cobb 500 chicks, in two growing phases (1 to 21 and 1 to 42 days old) were randomly assigned to […]

The experiment was carried out with the objective of determining the apparent and true ileal digestibilities of amino acids from five different poultry by-product. Ten crossbreed swines, castrated males, averaging 31.11 ± 3.88 kg were used in the experiment. The animals were previously submitted to the surgery for simple T canula implantation and, then, allotted to a randomized block design with five treatments, four replicates and one animal per experimental unit. At the end of the first and second replicates, […]

One experiment was carried out to determine the energy value of feeding fats (refined soybean oil, refined canola oil, refined sunflower oil, poultry fat, fish oil and lard) for broilers. One hundred and sixty eight broilers averaging 22 days old were allotted to a complete randomized design with seven treatments and four replicates of six broilers. The experiment lasted 8 days, with three days for adaptation and five days for excreta collection. The control replaced 20% of basal diet, as-fed […]