Data/hora: 23/06/2024 23:24:06

Biblioteca(s): | Embrapa Gado de Leite.
Data corrente: | 14/06/2017
Data da última atualização: | 30/11/2017
Autoria: | SIQUEIRA, L. G. B.
Afiliação: | LUIZ GUSTAVO BRUNO SIQUEIRA, CNPGL.
Título: | Developmental programming of the bovine embryo by in vitro fertilization and the maternal embryokine colony-stimulating factor 2.
Ano de publicação: | 2017
Fonte/Imprenta: | 2017.
Páginas: | 181 f.
Idioma: | Inglês
Notas: | Tese (Doutorado em Biologia Celular e Molecular Animal) - University of Florida, Gainesville, FL.
Conteúdo: | Abstract: Abnormak fetuses, neonates, and adult offspring derived by assisted reproductive technologies (ART) have been reported in humans and mice and have been associated with invreased likelihood of certain adult diseases. Matternally-derived molecules that are missing furing culture may lead to these abnormalities. In this study, a series of experiments evaluated the effects of in vitro embryo-production (IVP) on bovine embryonic, fetal, and postnatal development. We also took advantage of the controlled environment during culture to test whether a maternal embryokine, colony-stimulating factor 2 (CSF2), could embryo and fetal programming if apllied from days 5 to 7 of development. First, a retrospective cohort study was conducted to determine the pulative effects of ART on postnatal mortality, growth, and adult performance of dairy cattle. Offspring derived by IVP with reverse-sorted semen were at increased risk of mortality in the first 6 months of age, had altered birth weight and growth trajectory until puberty, and a slightly decrease in milk, fat, and protein production during their first lactation as adult cows. In the secod study, it was found that culture of embryos in vitro until day 7 of development was associated with altered fetal development at day 86 of gestation. CSF2 not abolish adverse effects of culture on morphometric features of the fetus, but did alter gene expression in liver, and muscle. Finally, it was tested whether CSF2 would affect embryonic development differently for female than male mebryos. CSF2 affected embryonic development to the blastocyst stage in females, but not males. Sexual dimorphism was observed in gene expression of morulae, in which level of expression of ~35% of the 92 genes examined dependend on sex. The effect of CSF2 was modified by sex in five genes, including developmentally important ones (e.g. NANOG and POU5F1). In conclusion, 1) procedures associated with IVP with reverse-sorted semen results in alterations of embryonic programming and consequences that persist postnatally and impact adult productive performance; 2) CSF2 can act as a developmental programming agent, but this embryokine alone was not able to abolish adverse effects of IVP on fetal development; and 3) responses of abryos to CSF2 depends upon embryo sex.
Palavras-Chave: | Colony-stimulating factor 2; Production in vitro.
Categoria do assunto: | G Melhoramento Genético
Registro original: | Embrapa Gado de Leite (CNPGL)
Exemplares: | CNPGL - (23556-1) - UPA - TS - PP - 2017.00006 - SIQ - 2017.00006 - DIS