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1.
J Dairy Sci ; 107(7): 4685-4692, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38310956

RESUMO

Genetic improvement in small countries rely heavily on foreign genetics. In an importing country such as Uruguay, consideration of unknown parent groups (UPG) for foreign sires is essential. However, the use of UPG in genomic model evaluations may lead to bias in genomic estimated breeding values (GEBV). The objective of this study was to study different models including UPG or metafounders (MF) in the Uruguayan Holstein evaluation and to analyze bias, dispersion, and accuracy of GEBV predictions in BLUP and single-step genomic BLUP (ssGBLUP). A gamma matrix (Γ) was estimated either by using base allele population frequencies obtained by bounded linear regression (MFbounded), or by using 2 values to design Γ (i.e., a single value for the diagonal and a different value for the off-diagonal [MFrobust]). Both Γ estimators performed well in terms of GEBV predictions, but MFbounded was the best option. There is, however, some bias whose origin was not completely understood. UPG or MF seem to model correctly genetic progress for unknown parents except for the very first groups (earlier time period). As for validation bulls, bias was observed across all models, whereas for validation cows it was only observed with UPG in BLUP. Overdispersion was found in all models, but it was mostly detected in validation bulls. Ratio of accuracies indicated that ssGBLUP gave better predictions than BLUP.


Assuntos
Cruzamento , Modelos Genéticos , Linhagem , Animais , Bovinos/genética , Feminino , Masculino , Uruguai , Genômica , Genoma , Genótipo , Fenótipo
2.
J Anim Breed Genet ; 135(3): 186-193, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29732622

RESUMO

The aim of this study was to estimate the genetic parameters of performance in a 750-km, 15-day ride in Criollo horses. Heritability (h2 ) and maternal lineage effects (mt2 ) were obtained for rank, a relative placing measure of performance. Additive genetic and maternal lineage (rmt) correlations among five medium-to-high intensity phase ranks (pRK) and final rank (RK) were also estimated. Individual records from 1,236 Criollo horses from 1979 to 2012 were used. A multivariate threshold animal model was applied to the pRK and RK. Heritability was moderate to low (0.156-0.275). Estimates of mt2 were consistently low (0.04-0.06). Additive genetic correlations between individual pRK and RK were high (0.801-0.924), and the genetic correlations between individual pRKs ranged from 0.763 to 0.847. The pRK heritabilities revealed that some phases were explained by a greater additive component, whereas others showed stronger genetic relationships with RK. Thus, not all pRK may be considered as similar measures of performance in competition.


Assuntos
Cavalos/genética , Modelos Genéticos , Resistência Física , Animais , Cruzamento , Feminino , Cavalos/fisiologia , Herança Materna , Modelos Estatísticos , Uruguai
4.
Am J Trop Med Hyg ; 35(1): 197-211, 1986 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-3946738

RESUMO

The largest and most extensive documented dengue epidemic in Puerto Rico struck an estimated 355,000 Puerto Rican residents from July-December 1977. The mixed epidemic of dengue types 2 and 3 coincided with a Caribbean pandemic of dengue type 1, first introduced into the western hemisphere in early 1977 and into Puerto Rico in the fall of that year. Health officials assembled a team to assess the epidemic and mounted a campaign to end it. Attempts to monitor the incidence and spread of dengue were confounded by simultaneous co-circulation of influenza virus, underscoring problems in formulating public health strategies dependent on nonspecific clinical and epidemiologic case criteria, and the need for rapid and reliable diagnostic capabilities. Despite co-circulation of multiple dengue serotypes, a risk factor associated with severe and fatal dengue hemorrhagic fever (DHF) in Southeast Asia, hospital and death certificate surveillance disclosed no cases of DHF in Puerto Rico. The epidemic serves as a reminder that when preventive measures are impossible or infeasible, developed countries with high living standards may be susceptible to large scale epidemics of infectious diseases.


Assuntos
Antígenos Virais/análise , Dengue/epidemiologia , Surtos de Doenças , Aedes/microbiologia , Custos e Análise de Custo , Dengue/microbiologia , Dengue/prevenção & controle , Dengue/transmissão , Vírus da Dengue/classificação , Vírus da Dengue/imunologia , Surtos de Doenças/microbiologia , Educação , Humanos , Controle de Insetos , Insetos Vetores/microbiologia , Porto Rico , Sorotipagem
7.
Am J Trop Med Hyg ; 28(6): 1040-4, 1979 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-507281

RESUMO

During the period July-December 1977, a widespread epidemic of dengue fever occurred in Puerto Rico. The cost of the epidemic was calculated, using upper and lower limit incidence figures, in terms of direct costs (medical care and epidemic control measures) and indirect costs (lost production of ill workers and parents of ill children). Direct costs were estimated to range between $2.4 and $4.7 million. Indirect costs were calculated by using current (1977) employment and wage data and population extrapolations from the 1970 census, and entailed a loss to the Puerto Rico economy of from $3.7 to $10.9 million. The total cost of this epidemic, therefore, was estimated to be in a range of $6.0 to $15.6 million, of which epidemic control measures comprised 7.8--20.2%.


Assuntos
Custos e Análise de Custo , Dengue/economia , Surtos de Doenças/epidemiologia , Adolescente , Adulto , Criança , Pré-Escolar , Dengue/epidemiologia , Feminino , Humanos , Lactente , Masculino , Porto Rico
9.
Am J Trop Med Hyg ; 27(6): 1216-24, 1978 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-727327

RESUMO

During the 1975 dengue epidemic in Puerto Rico, we studied three patients who had serologically confirmed dengue with hemorrhagic manifestations. None of the patients went into shock and none died. Only one of the patients had disease that resembled dengue hemorrhagic fever (DHF) as observed in Southeast Asia. This patient was a 14-year-old boy who had epistaxis, a positive tourniquet test, moderate thrombocytopenia, and significant hemoconcentration. The other two patients had hemorrhagic disease which was of clinical importance, but was not typical of DHF. These cases of dengue with hemorrhagic manifestations are the only ones known to have been documented in Puerto Rico.


Assuntos
Dengue/diagnóstico , Adolescente , Adulto , Dengue/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Porto Rico , Testes Sorológicos
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