Type

Journal Article

Authors

Mark Crowe
Niamh Forde
Patrick Lonergan
J. F. Roche
Marijke Eileen Beltman

Subjects

Veterinary

Topics
corpus luteum blood heifers cattle luteal phase embryo survival survival rate low progesterone

Evaluation of models to induce low progesterone during the early luteal phase in cattle (2009)

Abstract Two experiments were designed to evaluate models for generation of low circulating progesterone concentrations during early pregnancy in cattle. In Experiment 1, 17 crossbred heifers (Bos taurus) were assigned to either prostaglandin F2α (PGF2α) administration on Days 3, 3.5, and 4 (PG3; n = 9) or to control (n = 8). Blood samples were collected from heifers from Days 1 to 9 for progesterone assay. Progesterone concentrations were decreased (P < 0.03) between 18 and 48 h after first PGF2α treatment in heifers assigned to PG3 compared with that of controls. In Experiment 2, 39 crossbred heifers detected in estrus were inseminated (Day 0) and assigned to either (1) PGF2α administration on Days 3, 3.5, and 4 (PG3; n = 10), (2) PGF2α administration on Days 3, 3.5, 4, and 4.5 (PG4; n = 10), (3) Progesterone Releasing Intravaginal Device (PRID) insertion on Day 4.5 with PGF2α administration on Days 5 and 6 (PRID + PGF2α; n = 10), or (4) control (n = 9). Blood samples were collected daily until Day 15, and conceptus survival rate was determined at slaughter on Day 16. Progesterone concentrations during the sampling period in the PG3 and PG4 groups did not differ but were less than that of controls (P < 0.01). After an initial peak, progesterone concentrations in the PRID + PGF2α group were similar to that of controls. More heifers in the PG4 group (6 of 10) had complete luteal regression than did those in the PG3 group (3 of 10). Conceptus survival rate on Day 16 did not differ between groups. There was a significant correlation between progesterone concentration on Days 5 and 6 and conceptus size on Day 16. In summary, treatment with PGF2α on Days 3, 3.5, and 4 postestrus appeared to provide the best model to induce reduced circulating progesterone concentrations during the early luteal phase in cattle.
Collections Ireland -> University College Dublin -> Veterinary Medicine Research Collection (superseded in 2015)
Ireland -> University College Dublin -> College of Agriculture, Food Science and Veterinary Medicine (superseded in 2015)
Ireland -> University College Dublin -> School of Veterinary Medicine (superseded in 2015)

Full list of authors on original publication

Mark Crowe, Niamh Forde, Patrick Lonergan, J. F. Roche, Marijke Eileen Beltman

Experts in our system

1
M A Crowe
University College Dublin
Total Publications: 101
 
2
N Forde
University College Dublin
Total Publications: 53
 
3
P. Lonergan
University College Dublin
Total Publications: 190
 
4
J. F. Roche
University College Dublin
Total Publications: 111
 
5
Marijke Eileen Beltman
University College Dublin
Total Publications: 24