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| Cavalcante Neto,A.; Lui,J.F.; Sarmento,J.L.R.; Ribeiro,M.N.; Monteiro,J.M.C.; Fonseca,C.; Tonhati,H.. |
| The effect of environmental and genetic effects on the farrowing interval in Dalland (C-40) sows in the Southeast of Brazil was studied. Data consisting of 1,013 farrowing intervals recorded in two herds were analyzed, using a model that included the sire and the dam as random effects and the year of farrowing, the herd and the farrowing season as fixed effects, plus the covariables sow's age at farrowing, litter size at birth, lactation length and weaning-estrus interval. For the farrowing interval first only, variance components were estimated by REML, with an animal model that included, as fixed effect, a contemporary group and, as random effects, the additive genetic variance and the error. The mean farrowing interval was 140.9+5.7 days, with a 4.0%... |
| Tipo: Info:eu-repo/semantics/report |
Palavras-chave: Suíno; Característica reprodutiva; Herdabilidade; Produtividade. |
| Ano: 2009 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-09352009000100040 |
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| Rocha,J.C.M.C.; Tonhati,H.; Alencar,M.M.; Lôbo,R.B.. |
| Variance components were estimated for gestation length fitting the additive direct effect of calf, maternal genetic effect and sire effect as random effects. The statistical models also included the fixed effects of contemporary group, that included the date of breeding (AI), date of birth, and sex of calf, and the covariate age of dam at calving (linear and quadratic). Two different models were used, model 1 considering GL as a trait of the calf, and model 2 considering GL as a trait of the dam. The means of gestation length for the purebred animals were 294.55 days (males) and 293.34 days (females), while for the crossbred animals they were 292.49 days (males) and 292.55 days (females). Variance components for the purebred animals, fitting model 1, were... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Beef cattle; Gestation length; Heritability; Repeatability. |
| Ano: 2005 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-09352005000600013 |
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| Marcondes,C.R.; Gavio,D.; Bittencourt,T.C.C.; Rocha,J.C.M.C.; Lôbo,R.B.; Bezerra,L.A.F.; Tonhati,H.. |
| Foram obtidas estimativas de parâmetros genéticos e preditas DEPs (diferença esperada na progênie) para pesos não-padronizados aos 120 dias de idade (PR120), à desmama (PR240), ao ano de idade (PR365), aos 15 meses (PR455) e ao sobreano (PR550), de 29.769 animais Nelore, adotando-se o método REML, sob modelo animal. Para características PR120, PR240, PR365 e PR455, o modelo completo incluiu efeitos aleatórios de animal, aditivo materno, de ambiente permanente da vaca e de resíduo, efeitos fixos de grupo de contemporâneos (GC) aos 120 dias de idade, ou à desmama, classe de idade da vaca ao parto (CIVP), e como covariável a idade do animal à época da pesagem. Para características pós-desmama (PR365, PR455 e PR550), consideraram-se dois modelos de análise:... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Bovino; Nelore; Parâmetros genéticos; (co)variância; Correlação entre classificações; Características de crescimento. |
| Ano: 2002 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-09352002000100014 |
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| Tonhati,H.; Muñoz,M.F.C.; Duarte,J.M.C.; Reichert,R.H.; Oliveira,J.A.; Lima,A.L.F.. |
| Correction factors for milk yield at 90, 240, 270 and 305 days of lactation of buffaloes and genetic and environmental parameters for milk yield of these lactation periods were estimated. The data used consisted of 3888 lactation records of 1630 buffaloes from 10 herds reared in the State of São Paulo. Genetic parameters were estimated by the derivative free restricted maximum likelihood method, fitting an animal repeatability model. Heritability estimates for milk yield corrected for 90, 240, 270 and 305 days of lactation were 0.17, 0.15, 0.14 and 0.14, respectively. In this same order, repeatability estimates were 0.40, 0.44, 0.41 and 0.41. The genetic correlation estimates between these corrected milk yields ranged from 0.96 to 1.00. The multiplicative... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Buffalo; Lactation length; Milk yield. |
| Ano: 2004 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-09352004000200016 |
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| Cavalcante Neto,A.; Lui,J.F.; Sarmento,J.L.R.; Ribeiro,M.N.; Monteiro,J.M.C.; Fonseca,C.; Tonhati,H.. |
| The genetic and environmental factors that affect age at first conception (AFC) of gilts were evaluated, using 466 observations of Dalland animals (C-40). The software program MTDFREML was used to assess the genetic parameters on an animal model that included as fixed effect, contemporary group and, as random effects, the additive genetic, the common litter and the error. Mean value of AFC was 241.12±25.9 days, with CV of 8.5 %. Variance analysis showed that year (P<0.01), season (P<0.01) and herd effects (P<0.01) were important sources of variation of AFC. The throat effect (P=0.34) was not important for the AFC, but the mother of the gilts (P<0.01) was an important source of variation. The heritability estimate was 0.44±0.14 that this trait... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Suíno; Fatores não genéticos; Parâmetro genético; Puberdade. |
| Ano: 2008 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-09352008000200035 |
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