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Published on: April 7, 2023
Ovariectomy improves lactation persistency in dairy cows
1INRA UMR 1348 Physiologie, Environnement et Génétique pour l'Animal et lSystèmes d'Elevage, F-35000 Rennes, France.
Journal of Dairy Science
|June 23, 2012
Summary
Ovariectomy in dairy cows improved lactation persistency by reducing mammary gland cell death and tissue remodeling. This surgical intervention limited milk yield decline after peak lactation, offering a new strategy for dairy management.
Area of Science:
- Animal Science
- Dairy Science
- Reproductive Physiology
Background:
- Improving lactation persistency is a key goal in the dairy industry.
- Lactation persistency is influenced by management and physiological factors affecting mammary gland apoptosis and tissue remodeling.
- Ovarian steroids are suggested to negatively impact milk yield post-lactation peak.
Purpose of the Study:
- To investigate the effect of ovariectomy on lactation persistency in dairy cows.
- To determine if removing ovarian steroid secretion impacts mammary gland apoptosis and tissue remodeling.
- To assess the influence of ovariectomy on milk yield decline after the lactation peak.
Main Methods:
- Ovariectomy or sham operations were performed on multiparous Holstein × Normande crossbred cows at peak lactation.
- Milk yield was recorded daily for 14 months.
- Mammary epithelial cell apoptosis and tissue remodeling were assessed post-slaughter.
Main Results:
- Ovariectomized cows exhibited improved lactation persistency, with an average daily milk gain of 2.5 kg compared to sham-operated cows from months 6 to 14.
- Ovariectomy reduced mammary epithelial cell apoptosis, indicated by decreased poly(adenosine diphosphate-ribose) polymerase expression.
- Mammary tissue remodeling was limited in ovariectomized cows, evidenced by reduced matrix metalloproteinase activity.
Conclusions:
- Removal of ovarian secretion through ovariectomy enhances lactation persistency in dairy cows.
- Ovariectomy mitigates the decline in milk yield post-peak lactation by modulating mammary gland apoptosis and tissue remodeling.
- This study suggests a potential physiological approach to improve dairy cow milk production longevity.
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