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Mostrando ítems 2101-2110 de 4616
Índice de seleção bioeconômico para fêmeas de corte da raça nelore
(2012-12-01)
The reproductive efficiency of Nellore females was described on the basis of sexual precocity, staying productive in the herd (NP), maternal productivity (PM) and estimated cost for maintenance (CM). The combination of ...
Use of survival analysis as a tool for the genetic improvement of age at first conception in Nellore cattle
(Blackwell Publishing, 2006-02-01)
Restricted breeding seasons in beef cattle lead to censoring of reproductive data. In this paper, age at first conception (AFC) of Nellore females exposed to the sires for the first time between 11 and 16 months of age, ...
Genetic parameters for milk yield, age at first calving and interval between first and second calving in milk buffaloes
(Pagepress Publ, 2007-01-01)
Genetic parameters for the relation between the traits of milk yield (MY), age at first calving (AFC) and interval between first and second calving (IBFSC) were estimated in milk buffaloes of the Murrah breed. In the study, ...
Identification of QTLs associated with citrus resistance to Phytophthora gummosis
(Polish Academy of Sciences, Institute of Plant Genetics, 2006-01-01)
Citrus gummosis, caused by Phylophthora spp., is an important citrus disease in Brazil. Almost all citrus rootstock varieties are susceptible to it to some degree, whereas resistance is present in Poncirus trifoliata, a ...
Comparison of factor-analytic and reduced rank models for test-day milk yield in Gyr dairy cattle (Bos indicus)
(2013-09-27)
We analyzed 46,161 monthly test-day records of milk production from 7453 first lactations of crossbred dairy Gyr (Bos indicus) x Holstein cows. The following seven models were compared: standard multivariate model (M10), ...
Puberty in South American Bos indicus (Zebu) cattle
(Elsevier B.V., 2004-07-01)
Puberty in Zebu heifers follows a pattern characterized by a decrease in the steroid feedback mechanism and an increase in LH concentration, which result in the first ovulation followed by a short estrous cycle and the ...
Abordagens freqüentista e bayesiana para avaliação genética de bovinos da raça Canchim para características de crescimento
(Revista Brasileira Zootecnia Brazilian Journal Animal Sci, 2007-01-01)
This study aimed to: a) to compare the covariance components obtained by Restricted Maximum Likelihood (REML) and by bayesian inference (BI): b) to run genetic evaluations for weights of Canchim cattle measured at weaning ...
Variance heterogeneity for milk yield in Brazilian and Colombian Holstein herds
(2004-04-01)
Heterogeneity of variances for milk yield (MY) was determined for Brazilian and Colombian herds. The herds were grouped as high or low variability within each country, using as criterion the phenotypic standard deviation ...
Interacción genotipo x ambiente sobre el peso al destete de bovinos nelore en Brasil
(2008-07-25)
The objectives of this study were to evaluate the genotype x environmental interactions and estimates of genetic parameters for weaning weight (P205) in two Brazilian regions. Weights of Nellore calves (n= 46 390) were ...
Genetic susceptibility to bleomycin: A twin study
(1995-01-01)
The frequency of chromatid breaks was analysed in peripheral lymphocytes obtained from sixteen healthy monozygotic (MZ) and sixteen healthy dizygotic (DZ) pairs of twins. In addition, increases in the frequency of chromatid ...