The data were obtained from 51 herds to participate in the Nelore Catttle Breeding Program (NCBP) from the states of Goiás (GO), Mato Grosso do Sul (MS), Mato Grosso (MT), Minas Gerais (MG), São Paulo (SP), Maranhão (MA) and Bahia (BA). Were used to estimative genetic parameters for standardized weights at 120 (P120), 455 (P455) and 550 (550) days of age. Univariate and bivariate analysis were performed by animal model using MTDFREML program. For P120 was used a model that […]

Twelve Bos indicus (Nellore) embryo donors were confined receiving 25 kg maize silage and 2.5 kg concentrate supplement per day. The proteic supplements used were SOYA (S), SOYA+UREA (S+U) and UREA (U). After 20 day, embryo donors were superovulated and their embryos collected and cultivated in vitro until eclosion. There was no significant statistical difference between the three groups in total number of structures collected (4.17, 8.42 and 7.00), number of viable embryos (2.25, 3.50 and 4.33), oocytes (1.42, 3.92 […]

The follicular dynamics and luteal regression were studied in 12 Gir and seven Nelore cows, treated with analog prostaglandin F2a, between day 10 and 12 of the estrous cycle. The synchronization rate was higher than 92% for the two breeds, and the ovulation of second dominant follicle occurred in 72.7% of Gir and all Nelore cows. Ovulatory follicle diameter for Nelore was lower (11.0 ± 0.9 mm) than Gir cows (13.0 ± 1.7 mm). The average intervals from treatment to […]

Four cattle breeds (Gyr, Nellore, Guzerat and Holstein) were analyzed by amplification of genomic DNA using microsatellite loci to evaluate the genetic diversity within and among them. DNA samples of 18 animals from each breed were collected to access the genetic content of them. Allele frequencies were calculated and used to generate a Nei’s genetic distance matrix what was used to build a dendrogram following UPGMA clustering. As expected, Holstein breed was the most distinct from the other breeds: 1.15 […]

The use of pre-pubertal calves as oocyte donors offers a considerable potential to increase the genetic gain lowering the generations interval, as well as increase the usage of bovine females with high genetic value. The objectives of this study were to analyze the effect of age and of the stimulatory treatment with gonadotropins in the follicular response, the recovery rate, quantity and quality of oocytes of the prepubertal Nelore (B. t. indicus) calves. Twelve Nelore prepubertal females were stimulated with […]

Dairy goat production in Brazil, although firmly established since a few decades, has proved to be totally dependent on foreign countries for genetic improvement. Most herds presently producing are based on imported animals, and genetic refreshment is obtained through imported semen. No information is available on the genetic values and their evaluation along the years. In this paper, heritability and repeatability estimates, obtained through REML, are reported for milk yield. The values were 0.21557 and 0.21564, respectively. The BLUP method […]

The objective of this work was to study carcass and meat quantitative and qualitative characteristics of Hereford (H), 1/2 Jersey 1/2 H (JH) and 5/8 H 3/8 Nellore (HN) steers. Twenty-four castrated males, being eight of each genetic group, fed in feedlot since the weaning at seven months until the slaughter at fourteen months of age, were used. Slaughter weight was similar among genotypes, but the hot and the cold carcass weights were higher for the H (220.6 kg and […]

Total milk yield per lactation (PL), milk yield in 305 days (PL305) and lactation length (DL) were estimated based on records of the Brazilian Association of Girolando Breeders (3,574 lactations). Milk production was recorded monthly and 10.8% of the herds were raised under an extensive feeding system, 67.9% under a semi-intensive feeding system and 21.3% under an intensive feeding system. Data were analyzed through the least square method by GLM procedure (SAS, 1996). Preliminary analysis indicated a high interaction between […]

Data from 32,779 monthly milk production, from 3,605 lactations until 305 days (PL305), from 2,082 Gir cows, sired by 281 bulls, calving from 1987 to 1999, in 11 herds, were used to verify the viability of using daily milk production control (PLDC) to perform genetic evaluations within Gir breed. Bivariate analysis on PLDC1 to PLDC10 and PL305 were performed utilizing the restricted maximum likelihood method within an animal model, which included the three first lactations as replicate measures of the […]

Data from 32,779 monthly milk production, from 3,605 lactations until 305 days (PL305), from 2,082 Gir breed cows, sired by 281 bulls, calving from 1987 to 1999, in 11 herds, were utilized to verify the viability of using daily milk production control (PLDC) in sires genetic evaluation. Univariates analysis for PLDC1 to PLDC10 and Pl305 were performed utilizing the restricted maximum likelihood method within an animal model, which included the three first lactations as replicate measures of the same dams […]