Type

Journal Article

Authors

J. F. Roche
M P Boland
L J. Spicer
K McConnell
M A Crowe
W J. Enright
M G Murphy

Subjects

Veterinary

Topics
luteal phase body weight estrus blood progesterone female cattle animals ovarian follicle physiology animal nutritional physiological phenomena

Effect of dietary intake on pattern of growth of dominant follicles during the oestrous cycle in beef heifers. (1991)

Abstract Friesian x Hereford heifers (n = 19; mean +/- s.e.m. body weight (BW) = 375 +/- 5 kg) were used in a randomized incomplete block design. Heifers were fed 0.7 (n = 7; L), 1.1 (n = 7; M) or 1.8% (n = 5; G) of BW in dry matter (DM)/day for 10 weeks. Ovaries were examined by ultrasound, for one oestrous cycle, from week 5 of treatment. Maximum diameter of dominant follicles was smaller (P less than 0.05) in L (11.8 +/- 0.1 mm) than in M (13.7 +/- 0.2 mm) or G (13.2 +/- 0.3 mm) heifers. Growth rate (mm/day) of dominant follicles during the oestrous cycle was not affected (P greater than 0.05) by dietary intake. Persistence of dominant follicles was shorter (P less than 0.05) in L (9.8 +/- 0.2 days) than in M (11.9 +/- 0.3 days) or G (12.7 +/- 0.4 days) heifers. Three dominant follicles were identified during the oestrous cycle of 5 of 7 L, 3 of 7 M and 1 of 5 G heifers (P less than 0.10); 2 dominant follicles were identified in the remaining heifers (n = 2 of 7, 4 of 7 and 4 of 5, respectively). Length of the luteal phase and luteal-phase concentrations of progesterone were not affected (P greater than 0.05) by treatment. Low dietary intake reduced the diameter and persistence of dominant follicles during the oestrous cycle of beef heifers and tended to increase the proportion of oestrous cycles with 3 dominant follicles.
Collections Ireland -> University College Dublin -> PubMed

Full list of authors on original publication

J. F. Roche, M P Boland, L J. Spicer, K McConnell, M A Crowe, W J. Enright, M G Murphy

Experts in our system

1
M P Boland
University College Dublin
Total Publications: 103
 
2
M A Crowe
Teagasc
Total Publications: 102
 
3
Madeline Murphy
University College Dublin
Total Publications: 37