Phospholipid composition and resistance to vitrification of in vivo blastocyst of a Brazilian naturalized porcine breed

J.F.W Sprícigo,L.O Leme,M.A.N Dode,A.F Ramos,N.H Moreira,J.C Oliveira Neto,I Pivato,B.D.M Silva,P.C.P Silva,A.L Guimarães

doi:10.1590/1678-4162-10249

Abstract

ABSTRACT Piau porcine blastocysts were submitted to MALDI-TOF to identify the main phospholipids (PL). After that, in vivo blastocysts (D6) were vitrified (n=52), non-vitrified were used as control (n=42). After warming, blastocysts were in vitro cultured to assess re-expansion and hatching at 24 and 48 hours. Finally, at 48 hours, hatched blastocysts were submitted to RT-qPCR searching for BCL2A1, BAK, BAX and CASP3 genes. For MALDI-TOF, the ion intensity was expressed in arbitrary units. Blastocyst development was compared by Qui-square (P< 0.05). Among the most representative PL was the phosphatidylcholine [PC (32:0) + H]+; [PC (34:1) + H]+ and [PC (36:4) + H]+. Beyond the PL, MALDI revealed some triglycerides (TG), including PPL (50:2) + Na+, PPO (50:1) + Na+, PLO (52:3) + Na+ and POO (52:2) + Na. Re-expansion did not differ (P> 0.05) between fresh or vitrified blastocysts at 24 (33.3%; 32.7%) or 48 hours (2.4%; 13.5%). Hatching rates were higher (P< 0.05) for fresh compared to vitrified at 24 (66.7%; 15.4%) and 48 hours (97.6%; 36.0%). BAX was overexpressed (P< 0.05) after vitrification. In conclusion, Piau blastocysts can be cryopreserved by Cryotop. This study also demonstrated that the apoptotic pathway may be responsible for the low efficiency of porcine embryo cryopreservation.

Highlights

This study demonstrated that the apoptotic pathway may be responsible for the low efficiency of porcine embryo cryopreservation
The pig industry is mainly based on high technology and intensive production systems using breeds with high genetic standards that are specialized for meat production (Davoli and Braglia, 2007; Fao, 2009; Gilbert et al, 2015)
Naturalized pig species are known as animals that directly descend from those brought to South America by the colonizers between the XVII and XIX centuries

Summary

Introduction

The pig industry is mainly based on high technology and intensive production systems using breeds with high genetic standards that are specialized for meat production (Davoli and Braglia, 2007; Fao, 2009; Gilbert et al, 2015). Naturalized pig species are known as animals that directly descend from those brought to South America by the colonizers between the XVII and XIX centuries. Those animals adapted to the local conditions, such as the climate and topography. The naturalized pig breeds of Brazil are characterized by their rusticity, resistance to diseases, and low requirements for management and feeding, as well as their high adaptability to Brazilian tropical conditions. Of those naturalized pig breeds, the Piau is the most notorious. The conservation of that germplasm into a gene bank is important for several reasons, such as genetic uniqueness, traits of economic importance, adaptation to a specific environment and cultural or historical value

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