Regulating estrus and therapy of repeat-breeder and anestrous Holstein heifers using Progesterone Releasing Intravaginal Devices (PRIDs).

Control of estrus and progesterone levels in heifers given intravaginal progesterone coils and injections of progesterone and estrogen.

Fifty-three mature Hereford-cross heifers, which were between day 0 and 3 of the estrous cycle, each had silastic coils containing 2.1 g progesterone inserted into the vagina where they remained for 12 days. Animals were assigned to treatment groups and were injected with (1) 5 mg estradiol benzoate, (2) as (1) + 50 mg progesterone or (3) as (1) + 200 mg progesterone at the time of insertion of...

Estrus synchronization and conception rate after a progesterone releasing intravaginal device (PRID) treatment from the early luteal phase in heifers.

The objective of the present study was to evaluate estrus synchronization and conception rate after progesterone releasing intravaginal device (PRID) treatment from the early luteal phase in the presence or absence of estradiol benzoate (EB) in heifers. Heifers (n=11) were assigned randomly to two treatments; insertion of a PRID containing 1.55 g progesterone with a capsule attached including 1...

Comparison of two intravaginal progesterone releasing devices in lactating dairy cows: blood progesterone profile and field

Effect of ACTH-challenge on progesterone and cortisol levels in ovariectomised repeat breeder heifers.

In order to investigate the potential influence of stress as a component of the repeat breeding syndrome, the adrenocortical capacity for steroid production was evaluated in ovariectomised dairy heifers. In repeat breeder heifers (RBH), marginally elevated plasma progesterone levels during oestrus, so-called suprabasal progesterone levels, have earlier been measured and are believed to impair f...

Induced and Synchronized Estrus in Cattle: Dose Titration of Estradiol Benzoate in Peripubertal Heifers and Postpartum Cows After Treatment with an Intravaginal Progesterone-Releasing Insert and Prostaglandin F2a

Peripubertal beef heifers (n = 57) and postpartum multiparous cows (n = 52) were used to determine the optimal dose of estradiol benzoate (EB) to induce and synchronize estrus after treatment with intravaginal progesterone inserts (IVP4, EAZI-BREED CIDR) . All females received an IVP4 for 7 d (d 0 = insertion day) with a 25-mg injection of PGF2a (Lutalyse) on d 6. At 24 to 30 h after IVP4 re...