Data/hora: 23/05/2024 04:56:15

Biblioteca(s): 	Embrapa Caprinos e Ovinos.	
Data corrente: 	23/03/2005	
Data da última atualização: 	23/03/2005	
Autoria: 	TRALDI, A. S.; LEBROEUF, B.; COGNIÉ, Y.; POULIN, N.; MERMILLOD, P.	
Título: 	Comparative results of in vitro in vivo survival of vitrified in vitro produced goats and sheep embryos.	
Ano de publicação: 	1999	
Fonte/Imprenta: 	Theriogenology, v. 51, n. 1, p. 175, 1999.	
Idioma: 	Inglês	
Notas: 	Edição de proceedings Annual Conference of the International Embryo Transfer Society, Québec City, Canadá, jan. 1999.	
Conteúdo: 	Different vitrification methods have been tested for murine and bovine IVF embryos, but not for caprine or ovine in vitro produced embryos. Few results are available related to lhe pregnancy rate obtained after transfer of vitrified-thawed in vitro produced embryos in theses species. The objective of the present work was to compare lhe post-thaw in vitro survival of goat and sheep in vitro produced and vitrified embryos in relation to lhe pregnancy rale and embryo survival after transfer. For both species, zygotes were produced at lhe same period of lhe year by IVM-IVF-ICV of slaughterhouse oocytes as previous described (Poulin, et al., AETE 1997, 238). For the in vitro survival study, a total of l77 blastocysts were produced and vitrified from 1022 goat oocytes (17%) and 124 from 610 sheep oocytes (20%). Goat zygotes had lower cleavage rale (p< 0.01) than sheep zygotes (47 vs 71%, respectively) but developed faster and at a higher rale in culture, resulting in 37% of cleaved oocytes developing to blastocysts in goat, compared to 28% in sheep. On day 9 post-insemination for the sheep and day 8 or 9 for lhe goat, lhe expanded and hatched blastocysts were selected and vitrified. Blastocysts were washed for 5 min in OCM , and plunged for 5 min in OCM containing 10% Glycerol (G), then 5 min in OCM containing 10% G and 20% Ehylene glycol (EG) and transfered to OCM containing 25% G and 25% EG. The embryos were rapidly aspirated in a 1 cm central part of a 0.25 plastic straw, the remained parts being filled with galactose 1.7M in OCM. For thawing lhe straws were hold for 5 sec in ror followed by 15 sec in a 20°C water bath and lhe content transferred into an empty petri dish, mixed and incubated for 5 min at room temperature. The embryos were washed for 5 min in OCM and cultured either in mSOF or on a granulosa cell monolayer (to evaluate their post-thawing in vitro survival). Some were transferred surgically (mini-laparotomy) to synchronized recipients at Day 7 of lhe cycle. The pregnancy rale and embryo survival were evaluated after transfer into 20 goat recipients and 34 sheep recipients (2.1 embryos per recipient). Pregnancy was diagnosed ultrasonographically and followed to term. A large difference was observed between lhe two species in the study of in vitro embryo survival (60%-106/177 vs 41%-51/124 for goat and sheep, respectively; p<0.01). In the in vivo study, the birth rale (45%-9/20 vs 15%-5/34; p<0.05) and embryo survival (30 %- i 13/43 vs 9%-7n6; p<0.01) were also significantly higher for goat than sheep. Ali kids were normal whereas lhe lambs tended to show excessive weight, dystocia and anomalies (2n) or perinatal death (5n). These data indicate that IVF sheep embryos are less competent to support lhe vitrification method utilized than goat embryos and for both species lhe in vitro survival rale after thawing is related to lhe in vivo survival. 	
Palavras-Chave: 	Vitrificação.	
Thesagro: 	Caprino; Criopreservação; Ovino; Reprodução Animal; Transferência de Embrião.	
Categoria do assunto: 	--	
Registro original: 	Embrapa Caprinos e Ovinos (CNPC)	
Exemplares: 	CNPC - (17563-1) - ADC - AP - -- -  -  - v.51,p.175 - DIS