Document Detail

Evaluating recipient and embryo factors that affect pregnancy rates of embryo transfer in beef cattle.
MedLine Citation:
PMID:  11480620     Owner:  NLM     Status:  MEDLINE    
The objectives of this experiment were to determine the effects of corpus luteum characteristics, progesterone concentration, donor-recipient synchrony, embryo quality, type, and developmental stage on pregnancy rates after embryo transfer. We synchronized 763 potential recipients for estrus using one of two synchronization protocols: two doses of PGF2alpha (25 mg i.m.) given 11 d apart (Location 1); and, a single norgestomet implant for 7 d with one dose of PGF2alpha (25 mg i.m.) 24 h before implant removal (Location 2). At embryo transfer, ovaries were examined by rectal palpation and ultrasonography. Of the 526 recipients presented for embryo transfer, 122 received a fresh embryo and 326 received a frozen embryo. Pregnancy rates were greater (P < 0.05) with fresh embryos (83%) than frozen-thawed embryos (69%). Pregnancy rates were not affected by embryo grade, embryo stage, donor-recipient synchrony, or the palpated integrity of the CL. Corpus luteum diameter and luteal tissue volume increased as days post-estrus for the recipients increased. However, pregnancy rates did not differ among recipients receiving embryos 6.5 to 8.5 days after estrus (P > 0.1). There was a significant, positive simple correlation between CL diameter or luteal tissue volume and plasma progesterone concentration (r = 0.15, P < 0.01 and r = 0.18, P < 0.01, respectively). There were no significant differences in mean CL diameter, luteal volume or plasma progesterone concentration among recipients that did or did not become pregnant after embryo transfer. We conclude that suitability of a potential embryo transfer recipient is determined by observed estrus and a palpable corpus luteum, regardless of size or quality.
A R Spell; W E Beal; L R Corah; G C Lamb
Publication Detail:
Type:  Evaluation Studies; Journal Article    
Journal Detail:
Title:  Theriogenology     Volume:  56     ISSN:  0093-691X     ISO Abbreviation:  Theriogenology     Publication Date:  2001 Jul 
Date Detail:
Created Date:  2001-08-01     Completed Date:  2001-10-04     Revised Date:  2003-11-14    
Medline Journal Info:
Nlm Unique ID:  0421510     Medline TA:  Theriogenology     Country:  United States    
Other Details:
Languages:  eng     Pagination:  287-97     Citation Subset:  IM    
Department of Animal Sciences and Industry, Kansas State University, Manhattan 66502, USA.
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MeSH Terms
Cattle / physiology*
Corpus Luteum / physiology
Dinoprost / pharmacology
Embryo Transfer / veterinary*
Estrus Synchronization
Pregnancy, Animal / physiology*
Pregnenediones / pharmacology
Progesterone / blood
Reg. No./Substance:
0/Pregnenediones; 25092-41-5/norgestomet; 551-11-1/Dinoprost; 57-83-0/Progesterone

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

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