Progesterone during the breeding season and pregnancy in female muskoxen on different dietary regimens

• Main Authors: Janice E. Rowell, Robert G. White, William E. Hauer
• Format: Article
• Language: English
• Published: Septentrio Academic Publishing 1997-02-01
• Series: Rangifer
• Subjects: estrous cycle; body condition; embryonic loss; abortion; progesterone; muskoxen
• Online Access: https://septentrio.uit.no/index.php/rangifer/article/view/1363

Previously, we documented lowered calving success in captive muskoxen raised for 6 years on a low nutritional plane. In an effort to identify causes of lowered calf production, we looked at serum progesterone during the breeding season in muskoxen raised on either a high (HP) or low (LP) nutritional plane. Complete cessation of estrous cycli-city in 2 parous cows was the only irregularity identified. Abortion and/or embryonic loss occurred in both HP and LP cows. We also compared progesterone during pregnancy between the 2 nutritional planes and lactating and non-lacta-ting cows. The timing of the rise and fall of the mid-pregnant progesterone peak was consistent with stage of gestation and apparently independent of time of breeding, diet or lactational status.