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Published on: August 2, 2017
Plasma progesterone concentration depends on sampling site in pigs
Juha V Virolainen1, Robert J Love, Anssi Tast
1Department of Clinical Veterinary Sciences, Faculty of Veterinary Medicine, University of Helsinki, Pohjoinen Pikatie 800, 04920 Saarentaus, Finland. juha.v.virolainen@helsinki.fi
Animal Reproduction Science
|March 16, 2005
Summary
Progesterone levels in the jugular vein were significantly lower than in the caudal vena cava in early pregnant gilts. Ovarian progesterone secretion showed an episodic pattern, potentially linked to LH pulses, unaffected by feeding regimens.
Area of Science:
- Reproductive Endocrinology
- Swine Physiology
Background:
- Progesterone is crucial for maintaining pregnancy.
- Understanding progesterone secretion patterns is vital for reproductive success in gilts.
Purpose of the Study:
- To compare progesterone concentrations in systemic (jugular) versus ovarian (caudal vena cava) blood in early pregnant gilts.
- To investigate the influence of different feeding regimens on progesterone secretion patterns.
Main Methods:
- Nineteen crossbred gilts were assigned to high (H-H), low (L-L), or low-high (L-H) feeding regimens.
- Catheters were placed in the jugular vein and caudal vena cava on day 19 of gestation.
- Blood samples were collected over 5 days (days 20-24) to measure progesterone concentrations.
Main Results:
- Progesterone concentrations were significantly lower in jugular vein samples compared to caudal vena cava samples across all feeding groups (P<0.001).
- An episodic pattern of progesterone release was observed in caudal vena cava samples, but not in jugular vein samples.
- Feeding regimens did not significantly alter plasma progesterone concentrations during days 20-24 of gestation.
Conclusions:
- Ovarian progesterone is released episodically into the vena cava in early pregnant gilts.
- These progesterone pulses may be temporally associated with luteinizing hormone (LH) pulses.
- Systemic sampling underestimates true ovarian progesterone secretion in gilts.
