The objective of the present study was to evaluate the effects of supplementation with detoxified castor meal (DCM) in the diet of ewes during pregnancy, partum, and post-partum on the weight development of their offspring and at slaughter. The study included 56 ewes with synchronized estrus that were naturally mated. At the beginning of pregnancy and in post-partum, hepatic and renal function-related parameters and progesterone levels were measured. At slaughter, the proximate composition and fatty acid profile were determined in […]

The objectives of this study were to evaluate reproductive traits (age at first calving and calving interval) and to obtain heritability estimates for birth weight in a crossbred (Murrah and Mediterranean breeds) Buffalo population in Rondonia State, Brazil. Data recorded between 1979 and 2001 were analyzed by SAS®. Variance components and heritability estimates were obtained by using the DFREML program. Age at first calving (1,291 ± 235 days) was significantly influenced by the contemporary group of dam. Calving interval (451 […]

This experiment was carried out to evaluate the development of 32 primiparous beef heifers Aberdeen Angus and Angus crossbred raised and mating from 13 to the 15 months of age. The experiment had beginning in the pregnancy diagnosis of using ultra-sound technique, realized at 28 days after the ending of the reproductive period. The initial average weight and body condition (BC) was 288 kg LW and 3.2 points, respectively. In this occasion, the beef heifers were uniformly distributed by genetic […]

The effect of hCG administration on reproductive performance of Alpine goats during the natural breeding season was evaluated. Thirty-two nulliparous and 124 lactating goats, after estrus identification and breeding, were randomly assigned according to the categories to two treatments. In T1 (n=75) and T2 (n=81) the animals received 1 mL of saline solution or 250 IU of hCG intramuscularly, respectively, five days after breeding. Pregnancy was detected and confirmed on days 35 and 70 after breeding by transabdominal ultrasonography (3.5 […]

The goal of this experiment was to evaluate if biostimulation may favourably change the reproductive performance of beef heifers on their first breeding season. For this purpose, 50 days before the artificial insemination (AI) period, 60 two-year-old heifers (Hereford x Nelore) were randomly distributed into two treatment groups: biostimulatated (BE) using a ruffian or not biostimulated (NE). The rates of cycling heifers before AI were 76 and 56% for BE e NE, respectively. Conception rates were 90 and 73% for […]

The investigation was carried out to evaluate the effects of two stocking rates (CA280= 280 kg LW/ha and CA=360= 360 kg LW/ha) and two weaning ages of calves (DC = Conventional weaning at seven months of age and DP= Early weaning at three/four months of age) on reproductive performance of primiparous beef cows of two breed compositions (½ Nelore ½ Hereford and ¼ Nelore ¾ Hereford). Average daily weight gain (GMD) from calving to DC, during the mating period, and […]

Records of start of breeding season and subsequent calving, from 1,247 Nelore females raised at Sertãozinho Experimental Station (IZ ¾ SP, Brazil), selected for high (selection and traditional lines) and for average (control line) yearling weights were used to compute days to calving and to study the effect of selection for yearling weight on reproductive performance. Data sets of heifers, and cow and heifers were analyzed with and without non-calvers females. There were no significant differences among the performance of […]

Genetic parameters for days to calving were estimated using a random regression model, with orthogonal polynomials of age at breeding season (in years) as covariable. The records of days to calving (4,118) came from 929 cows from three experimental Nelore herds, been the selection and traditional herds selected for higher yearling weight and the control herd selected for the mean of yearling weight. Genetic and permanent environmental variances were described by a fourth order polynomial function, with 9 measures of […]

The objective of this study was to evaluate the nutritive value of the diet by cows grazing in natural pastures, in a typical area of Nhecolândia sub-region, Pantanal, during two hydrological years: from October 1997 to September 1999. Grazed forage species samples, representative of the animals’ diet, were collected manually in each month. All forage samples were analyzed for crude protein (CP), acid detergent fiber (ADF), neutral detergent fiber (NDF), and lignin (LIG). Near infrared spectrofotometry (NIRS) was used to […]

The experiment was run at the Agronomic Experimental Station of the Federal University of Rio Grande do Sul, located in the district of Eldorado do Sul, Brazil. The objective of the study was to evaluate the effect of the date of early (01/05/99) or conventional (03/26/99) weaning on the reproductive performance of multiparous beef cows during two mating seasons, 98/99, and the subsequent, 99/00. Fifty cows had their calves weaned with an average age of 91 days old and a […]