Endocrine changes in sows weaned at two stages of lactation

Journal of Reproduction and Fertility
S Edwards, G R Foxcroft

Abstract

Plasma concentrations of LH, FSH, prolactin, oestradiol-17 beta and progesterone were determined in 18 multiparous sows at 4-h intervals for 15-18 days around weaning at 3 or 5 weeks post partum. Sampling at 10-min intervals for 6 h occurred every 2 days throughout the same period. Shortening lactation significantly reduced the preovulatory LH surge and altered the pattern of FSH release. However, there was no significant effect on ovulation rate or interval from weaning to oestrus between groups. Weaning was consistently associated with a significant rise in basal LH concentrations whilst FSH secretion remained unaffected. Lactation length did not appear to affect the characteristics of episodic LH secretion before weaning, nor were any consistent changes in LH secretion apparent until the preovulatory rise in LH. Plasma prolactin values declined rapidly at weaning and remained low thereafter. These results indicate that the 'trigger' controlling the return to cyclic ovarian activity after weaning in the pig is complex, but it is suggested that lactational anoestrus and anovulation result primarily from a lack of LH stimulation to the ovary.

Citations

Jun 1, 1991·Zentralblatt für Veterinärmedizin. Reihe A·T RojkittikhunH Kindahl
Apr 1, 1995·Zentralblatt für Veterinärmedizin. Reihe A·V T TsumaN Lundeheim
Jul 17, 2014·Animal Reproduction Science·Alice C WeaverWilliam H E J van Wettere
Jan 18, 2008·Reproduction in Domestic Animals = Zuchthygiene·R GerritsenB Kemp
Jan 18, 2008·Reproduction in Domestic Animals = Zuchthygiene·R GerritsenB Kemp
Jul 19, 2019·Animal : an International Journal of Animal Bioscience·C A Lents
Aug 21, 2003·Journal of Animal Science·H J WillisG R Foxcroft

❮ Previous
Next ❯

Related Concepts

Trending Feeds

COVID-19

Coronaviruses encompass a large family of viruses that cause the common cold as well as more serious diseases, such as the ongoing outbreak of coronavirus disease 2019 (COVID-19; formally known as 2019-nCoV). Coronaviruses can spread from animals to humans; symptoms include fever, cough, shortness of breath, and breathing difficulties; in more severe cases, infection can lead to death. This feed covers recent research on COVID-19.

Blastomycosis

Blastomycosis fungal infections spread through inhaling Blastomyces dermatitidis spores. Discover the latest research on blastomycosis fungal infections here.

Nuclear Pore Complex in ALS/FTD

Alterations in nucleocytoplasmic transport, controlled by the nuclear pore complex, may be involved in the pathomechanism underlying multiple neurodegenerative diseases including Amyotrophic Lateral Sclerosis and Frontotemporal Dementia. Here is the latest research on the nuclear pore complex in ALS and FTD.

Applications of Molecular Barcoding

The concept of molecular barcoding is that each original DNA or RNA molecule is attached to a unique sequence barcode. Sequence reads having different barcodes represent different original molecules, while sequence reads having the same barcode are results of PCR duplication from one original molecule. Discover the latest research on molecular barcoding here.

Chronic Fatigue Syndrome

Chronic fatigue syndrome is a disease characterized by unexplained disabling fatigue; the pathology of which is incompletely understood. Discover the latest research on chronic fatigue syndrome here.

Evolution of Pluripotency

Pluripotency refers to the ability of a cell to develop into three primary germ cell layers of the embryo. This feed focuses on the mechanisms that underlie the evolution of pluripotency. Here is the latest research.

Position Effect Variegation

Position Effect Variagation occurs when a gene is inactivated due to its positioning near heterochromatic regions within a chromosome. Discover the latest research on Position Effect Variagation here.

STING Receptor Agonists

Stimulator of IFN genes (STING) are a group of transmembrane proteins that are involved in the induction of type I interferon that is important in the innate immune response. The stimulation of STING has been an active area of research in the treatment of cancer and infectious diseases. Here is the latest research on STING receptor agonists.

Microbicide

Microbicides are products that can be applied to vaginal or rectal mucosal surfaces with the goal of preventing, or at least significantly reducing, the transmission of sexually transmitted infections. Here is the latest research on microbicides.