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1.
Animal ; 15(9): 100320, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34416556

RESUMO

The identification of the presence of genotype by environment interaction effects on important traits in Holstein cattle allows for the use of international genetic evaluations and a more efficient design of regional genetic evaluation programmes. The aim of this study was to determine the genotype × environment interaction effects in Chilean Holstein dairy cattle through the analysis of records corresponding to calvings between 1998 and 2015. Herds were classified in the central and southern regions of Chile based on herd location as well as by high and low levels of production environments based on the fat plus protein yield averages per herd within each region. The central region has a Mediterranean climate and a confined production system while the southern region has a humid temperate climate and a production system based on grazing with supplementation. Traits studied were milk yield (MY), fat yield (FY), protein yield (PY), fat content (FC) and protein content (PC) by lactation, age at first calving (AFC) and calving interval (CI). Several four-trait mixed animal models were applied to environmental category data as different traits, which included herd-year-calving season (herd-year-birth season for AFC) and lactation number as fixed effects, and animal additive genetic, sire-herd, permanent environment and residual effects as random effects. Genetic correlations (rg) for MY, FY, FC, PC and CI were found to decrease as differences between environmental categories increased. The rg between the most extreme environmental categories considered in this study for AFC (0.26) was the only one found statistically lower than 0.60. Genetic correlation values statistically lower than 0.80 (P < 0.05) were observed for AFC, CI, MY, FY and PY between some environmental categories. If separate genetic evaluations are adopted as practical criteria when the value of rg is lower than 0.60, the consequence of improving a multi-trait economic breeding objective in this population is likely to be small unless extreme environmental categories are considered. However, a moderate decrease in selection response and re-ranking of selection candidates is expected for AFC, CI and yield traits when selection is performed in different environmental conditions. Genotype × environment interaction effects involving production systems in a Mediterranean climate and confinement vs. Temperate Oceanic climate and grazing with supplementation, and between two fat plus protein yield level categories within each environment, were at most moderate for the studied traits.


Assuntos
Lactação , Leite , Animais , Bovinos/genética , Feminino , Genótipo , Parto , Fenótipo , Gravidez
2.
Behav Res Ther ; 34(1): 23-31, 1996 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8561761

RESUMO

A group treatment for hypochondriasis was administered to 14 subjects. It was based on Barsky, Geringer and Wool (1988) [General Hospital Psychiatry, 10, 322-327] cognitive-behavioral formulation and presented as an educational course to explain the origins of an enhanced perception of somatic symptoms. Initially, one experimental group (N = 9) and a waiting list control (N = 8) were formed. Experimental subjects showed significant reductions in illness fears and attitudes, reported somatic symptoms and dysfunctional beliefs. Waiting-list controls also changed some illness attitudes, but showed no change in somatic symptoms and increased the number of visits to doctors. Experimental and control subjects differed on several change measures. Afterwards, part of the waiting list subjects (N = 5) received treatment. Overall, treatment was effective for the target measures and produced long-term positive effects on other fears, dysphoric mood and well-being. After treatment, subjects were significantly more extroverted, open and warm. The clinical impression was that treatment was not limited to less severe cases.


Assuntos
Transtorno Depressivo/psicologia , Transtorno Depressivo/terapia , Adolescente , Adulto , Atitude Frente a Saúde , Terapia Comportamental , Terapia Cognitivo-Comportamental , Transtorno Depressivo/diagnóstico , Feminino , Humanos , MMPI , Masculino , Personalidade , Qualidade de Vida , Índice de Gravidade de Doença , Resultado do Tratamento
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