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Forskolin effect on the cryosurvival of in vitro-produced bovine embryos in the presence or absence of fetal calf serum

Published online by Cambridge University Press:  18 July 2012

Daniela Martins Paschoal ,
Mateus José Sudano ,
Midyan Daroz Guastali ,
Rosiára Rosária Dias Maziero ,
Letícia Ferrari Crocomo ,
Luis Carlos Oña Magalhães ,
Tatiana da Silva Rascado ,
Alicio Martins Jr  and
Fernanda da Cruz Landim-Alvarenga
Daniela Martins Paschoal*
Affiliation:
São Paulo State University, UNESP, School of Veterinary Medicine and AnimalScience, FMVZ, Department of Animal Reproduction and Veterinary Radiology, Rubião Jr. s/n°, Botucatu/SP, Brazil, 18618-970.
Mateus José Sudano
Affiliation:
São Paulo State University, UNESP, School of Veterinary Medicine and Animal Science, FMVZ, Department of Animal Reproduction and Veterinary Radiology, Rubião Jr. s/n°, Botucatu/SP, Brazil, 18618-970.
Midyan Daroz Guastali
Affiliation:
São Paulo State University, UNESP, School of Veterinary Medicine and Animal Science, FMVZ, Department of Animal Reproduction and Veterinary Radiology, Rubião Jr. s/n°, Botucatu/SP, Brazil, 18618-970.
Rosiára Rosária Dias Maziero
Affiliation:
São Paulo State University, UNESP, School of Veterinary Medicine and Animal Science, FMVZ, Department of Animal Reproduction and Veterinary Radiology, Rubião Jr. s/n°, Botucatu/SP, Brazil, 18618-970.
Letícia Ferrari Crocomo
Affiliation:
São Paulo State University, UNESP, School of Veterinary Medicine and Animal Science, FMVZ, Department of Animal Reproduction and Veterinary Radiology, Rubião Jr. s/n°, Botucatu/SP, Brazil, 18618-970.
Luis Carlos Oña Magalhães
Affiliation:
São Paulo State University, UNESP, School of Veterinary Medicine and Animal Science, FMVZ, Department of Animal Reproduction and Veterinary Radiology, Rubião Jr. s/n°, Botucatu/SP, Brazil, 18618-970.
Tatiana da Silva Rascado
Affiliation:
São Paulo State University, UNESP, School of Veterinary Medicine and Animal Science, FMVZ, Department of Animal Reproduction and Veterinary Radiology, Rubião Jr. s/n°, Botucatu/SP, Brazil, 18618-970.
Alicio Martins Jr
Affiliation:
São Paulo State University, UNESP, School of Veterinary Medicine, FMVA, Department of Clinical Surgery and Animal Reproduction, Clóvis Pestana, 793, Araçatuba/SP, Brazil, 16050-680.
Fernanda da Cruz Landim-Alvarenga
Affiliation:
São Paulo State University, UNESP, School of Veterinary Medicine and Animal Science, FMVZ, Department of Animal Reproduction and Veterinary Radiology, Rubião Jr. s/n°, Botucatu/SP, Brazil, 18618-970.
*
All correspondence to: Daniela Martins Paschoal. São Paulo State University, UNESP, School of Veterinary Medicine and AnimalScience, FMVZ, Department of Animal Reproduction and Veterinary Radiology, Rubião Jr. s/n°, Botucatu/SP, Brazil, 18618-970. Tel: +55 14 38116249. Fax: +55 14 38116326. e-mail: dmpaschoal@yahoo.com.br
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Summary

The objective of this study was to assess the viability and cryotolerance of zebu embryos produced in vitro with or without the addition of fetal calf serum (FCS) and forskolin (F). Embryos produced in vivo were used as a control. Presumptive zygotes were cultured in modified synthetic oviductal fluid supplemented with amino acids (SOFaa), bovine serum albumin (BSA) and with (2.5%) or without (0%) FCS. On day 6 of growth, the embryos from each group were divided into treatments with or without 10 μM F to induce embryonic lipolysis, comprising a total of four experimental groups: 2.5% FCS, 0% FCS, 2.5% + F and 0% + F. For vitrification, embryos were exposed to vitrification solution 1 (5 M EG (ethylene glycol)) for 3 min and then transferred to vitrification solution 2 (7 M EG, 0.5 M galactose solution and 18% (w/v) Ficoll 70) before being introduced to liquid nitrogen. The presence of FCS in the culture medium resulted in the production of embryos with a similar rate of damaged cells compared with in vivo-produced embryos. After vitrification, the 2.5% FCS group had a significantly higher rate of damaged cells when compared with the other groups (P < 0.05). The results of this experiment indicated that the omission of FCS and the addition of forskolin do not have deleterious effect on embryo production rates. In addition, embryos produced in the presence of FCS had greater sensitivity to cryopreservation, but this effect was reversed when forskolin was added to the medium, which improved embryo survival without affecting embryo development and quality after vitrification.

Keywords

EmbryoFetal calf serumForskolinIn vitro productionVitrification
Type
Research Article
Information
Zygote , Volume 22 , Issue 2 , May 2014 , pp. 146 - 157
Copyright
Copyright © Cambridge University Press 2012 

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