ABSTRACT The objective of this study was to determine the impact of metabolic changes occurring in induced subclinical gestation toxaemia in ewes on metabolic parameters and vigour in the first 72 h of their lambs’ life. Fifty-one adult Corriedale ewes of known gestation date and fed on a natural pasture were randomly divided into four groups at day 145 of gestation. Group A (ewes with single pregnancies) and group C (ewes with twin pregnancies) were fed on a natural pasture […]

ABSTRACT The objective was to evaluate factors that influence calving probability in the first and second reproductive years of beef heifers that reached the minimum recommended body weight (BW) in the first breeding season. Two hundred twenty-seven 24-month-old Charolais × Nellore heifers that mated between 2003 and 2012 were analyzed. The parameters evaluated were: year effect; individual and maternal heterozygosis; percentage of Charolais genotype; average daily gain (ADG) from weaning to the end of the first breeding season; BW at […]

ABSTRACT The objective of this research was to evaluate a possible corrective measure against negative metabolic states, as occurs in the advanced stage of gestation in ewes, and that sometimes produces a disease called pregnancy toxaemia. In the present research, we found that the joint administration of i.v. lysine-vasopressin (0.08 IU/kg body weight, BW) and an oral glucose solution (50 g) produces an increase in blood glucose, which persists for some time (up to 6 h); therefore, it could be […]

ABSTRACT The objective was to evaluate the accuracy of six body weight (BW) estimating methods in Mangalarga Marchador horses (MM) (n = 318): method A – tape placements at three different positions around the thoracic girth; B – Crevat and Quetelec’s formula; C – Hall’s formula; D – Hintz and Griffiths’ table; E – Santos’ table; and F – Cintra’s formula. For additional analyses, gender, age, and gestational stage were considered. Estimated average BW was compared to the actual scale […]

ABSTRACT The objective of this study was to determine the effect of supplemented organic selenium at different levels to concentrate feed of Norduz ewes in late pregnancy on maternal serum, placenta, colostrum, and offspring serum concentrations. This study was conducted using two-year-old 35 Norduz ewes. Ewes were randomly assigned to one of three dietary treatments for 57 days prepartum and at the seven days postpartum. Group 1 was fed a standard pregnant sheep concentrate basal diet without any additional Se […]

The objective of this study was to evaluate the efficiency of cyclic and acyclic progesterone-treated recipient mares in a commercial embryo transfer program. Acyclic recipients were treated with decreasing amounts of estradiol cypionate (ECP® – Pfizer Saúde Animal, São Paulo, Brazil), followed by 1500 mg of a sustained-release progesterone injection (P4LA150® – Laboratórios B.E.T., Rio de Janeiro, Brazil). Out of all 1506 embryo recovery attempts performed, 59.36% were positive (894/1506). Pregnancy rates of cyclic and acyclic mares were, respectively, 44.12% […]

This study evaluated yearling growth and reproductive performance of Hereford heifers at 24-26 months of age grazing on natural pastures at two stocking rates during winter and spring, associated or not to improved natural pastures. Heifers were classified according to three weight groups (Light, Medium and Heavy) and randomly distributed into four feeding management practices: 0.6 AU (1 animal unit = 450-kg body weight) – heifers on natural pastures at a stocking rate of 0.6 AU/ha; 0.8 AU – heifers […]

The objective of the study was to evaluate, for two consecutive years, the weaning age effect on the reproductive performance of 121 Bradford heifers mated at 13/15 months old. Two weaning ages were assessed: at 77 days, early weaning (EW) or at 147 days, conventional weaning (CW). The heifers were born in 2004 (66) and 2005 (55). After weaning, heifers were kept initially on cultivated summer pasture (Pennisetum americanum, L.) and afterward on cultivated winter/spring pasture (Avena strigosa Schreb plus […]

The effect was assessed of pre-mating supplementary feeding on the reproductive performance of 13-15 month old beef heifers. Eighty-nine heifers were used with a mean age of 12 months and mean body weight (BW) of 242 kg from three herds Aberdeen Angus heifers from the Santa Cecilia and Capitao Rodrigo ranches and crossbred Aberdeen Angus heifers) in a feeding system of only grazing pasture or supplemented heifers on pasture with milled corn grain. The supplement was offered daily at the […]

The effects of three feeding management were evaluated in the winter months (CN: natural pasture; CNS: natural pasture + supplementation; CNM: improved natural pasture) and three live weight groups (light, medium, heavy) on the subsequent reproductive performance of Brangus heifers with first service to 24/27 mo old. Feeding managements showed differences in the daily weight gain (DWG) during the winter (0.261, 0.376 and 0.679 kg/day) in body weight at the beginning of the reproductive period (302.8, 317.8 and 330.7kg for […]