Type

Journal Article

Authors

P. Lonergan
D Rizos
N Forde
F. Carter
P. Duffy
A K Kelly
V Maillo
S Scully
L O'Hara

Subjects

Microbiology

Topics
embryo implantation gonadotropin releasing hormone steroid isomerases multienzyme complexes veterinary progesterone reductase ovulation induction gene expression regulation embryo transfer progesterone female cattle fertility agents female administration dosage genetics metabolism ovarian follicle 3 beta hydroxysteroid oxidoreductase delta 5 cholesterol side chain cleavage enzyme fertilization in vitro corpus luteum 3 ketosteroid isomerase blood adverse effects steroidogenic acute regulatory protein suction uterus superovulation ultrasonography phosphoproteins time factors animals

Effect of follicular aspiration just before ovulation on corpus luteum characteristics, circulating progesterone concentrations and uterine receptivity in single-ovulating and superstimulated heifers. (2012)

Abstract The aim of this study was to investigate, in unstimulated and superstimulated heifers, the effect of follicle aspiration just before ovulation on corpus luteum (CL) development, circulating progesterone (P(4)) concentrations and the ability of the uterus to support embryo development. Following follicle aspiration or ovulation timed from GNRH administration, CL development was assessed by daily ultrasonography, and CL function was assessed in terms of the capacity to produce P(4) and the expression of genes involved in steroidogenesis in luteal tissue. The capacity of the uterine environment to support conceptus development was assessed following transfer and recovery of in vitro-produced embryos. Follicular aspiration just before the expected time of ovulation leads to a significant reduction in CL diameter, CL area and area of luteal tissue. This was associated with a decrease in circulating P(4) in both unstimulated and superstimulated heifers. Follicle aspiration leads to a reduction in conceptus length and area on day 14 in unstimulated heifers only. Follicle aspiration leads to a reduction in the expression of LHCGR in luteal tissue from unstimulated heifers compared with those in which the CL formed after ovulation. Superstimulation significantly reduced the expression of STAR in luteal tissue in both ovulated and follicle-aspirated heifers. In conclusion, in stimulated and unstimulated heifers, aspiration of the preovulatory dominant follicle(s) just before expected ovulation interferes with the subsequent formation and function of the CL, in terms of size and P(4) output and this, in turn, is associated with a reduced capacity of the uterus to support conceptus elongation in unstimulated heifers.
Collections Ireland -> University College Dublin -> PubMed

Full list of authors on original publication

P. Lonergan, D Rizos, N Forde, F. Carter, P. Duffy, A K Kelly, V Maillo, S Scully, L O'Hara

Experts in our system

1
P. Lonergan
University College Dublin
Total Publications: 190
 
2
D Rizos
University College Dublin
Total Publications: 42
 
3
N Forde
University College Dublin
Total Publications: 53
 
4
F. Carter
University College Dublin
Total Publications: 19
 
5
P. Duffy
University College Dublin
Total Publications: 42
 
6
Alan K Kelly
Teagasc
Total Publications: 83
 
7
V Maillo
University College Dublin
Total Publications: 8
 
8
S Scully
Teagasc
Total Publications: 7