Inhibitory Effects of CIDR-based Ovulation-synchronization Protocols on Uterine PGF2α Secretion at the Following Luteal Phase in Early Postpartum Non-cycling Beef Cows

Mitsuhiro SAKASE, Noritoshi KAWATE, Chikara NAKAGAWA, Moriyuki FUKUSHIMA, Masanobu NODA, Kazushi TAKEDA, Satoru UENO, Toshio INABA, Kayoko KIDA, Hiromichi TAMADA, Tsutomu SAWADA
2006 Journal of reproduction and development  
We investigated whether CIDR-based ovulation-synchronization protocols inhibit secretion of prostaglandin (PG) F2α from the uterus in the following luteal phase in non-cycling beef cows. Ten early (a month) postpartum non-cycling Japanese Black beef cows were treated with (1) Ovsynch (GnRH analogue on Day 0, PGF2α analogue on Day 7, and GnRH analogue on Day 9; n=3), (2) Ovsynch+CIDR (Ovsynch protocol plus a CIDR for 7 days from Day 0; n=4), or (3) estradiol benzoate (EB) Ovsynch+CIDR (EB on Day
more » ... 0 in lieu of the first GnRH treatment followed by the Ovsynch+CIDR protocol; n=3). An oxytocin challenge was administered on Day 24 to examine uterine PGF2α secretion. Plasma concentrations of 13,14-dihydro-15-keto-PGF2α were lower at 30-120 min after oxytocin administration in the Ovsynch+CIDR group and 75 min after administration in the EB Ovsynch+CIDR group than in the Ovsynch group (P<0.05). Plasma progesterone concentrations were higher from Days 1 to 7 in the Ovsynch+CIDR group and from Days 1 to 5 in the EB Ovsynch+CIDR group than in the Ovsynch group (P<0.05). The progesterone concentrations were higher on Days 27 and 29 in both CIDR-treated groups than in the Ovsynch group (P<0.05). In conclusion, in noncycling beef cows, CIDR-based ovulation-synchronization protocols inhibit uterine PGF22α secretion in the following luteal phase and prevent premature luteolysis as is seen with the Ovsynch protocol.
doi:10.1262/jrd.17108 pmid:16627952 fatcat:dsn6skswlvbctc4mzlsl34exna