The effect of GnRH administration on the serum LH response and ovulation in the early postpartum period of dairy cows

Vural R., Kuplulu S., Guven B., Ozsar S.

TURKISH JOURNAL OF VETERINARY & ANIMAL SCIENCES, vol.23, pp.1-5, 1999 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 23
  • Publication Date: 1999
  • Journal Name: TURKISH JOURNAL OF VETERINARY & ANIMAL SCIENCES
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.1-5
  • Keywords: GnRH, LH, early postpartum, dairy cows, POST-PARTUM, CATTLE, INTERRELATIONSHIPS, STEROIDS, HORMONE
  • Ankara University Affiliated: No

Abstract

The aims of this study were to determine whether GnRH would induce ovulation in dairy cows and to detect the acute changes in the serum luteinizing hormone (LH) alter GnRH administration on bay 14 postpartum. Ten holstein cows were divided into two groups: group I (n=6) and group II (Control, n=4). The six cows in group I received intramuscularly 0.5 mg gonadarelin and the four cows in group II were given intramuscularly 5 ml saline on day 14 postpartum. Ovarian activity and the size of the previously gravid uterine horn were monitored by rectal palpation and by the measurement of serum progesterone levels. The acute LH release in response to GnRH administration was evaluated from blood samples collected at 0 and 1,2,3,4,5 and 6 hours after injection.