Effects of restrictive suckling on postpartum reproductive performance in mares.

This research investigated the impact of a restrictive suckling schedule on the reproductive health of Quarter Horse mares and the growth and development of their foals. The study revealed that such a regimen could speed up the onset of estrus and ovulation in mares after giving birth, though it doesn’t impact the conception rates significantly, with no observed adverse effects on the foals.

Objective and Methodology of the Study

• This two-year experiment was carried out using a group of 30 quarter horse mares and their foals.
• The study had two main goals: firstly, to investigate the effects of a treatment regimen involving restrictive suckling on the postpartum reproductive performance of mares, and secondly, to study the impact of this system on the growth and development of the foals.
• The restrictive suckling procedure allowed for nursing of the foals for four one-hour periods each day.

Findings of the Study

• The mares subjected to the restricted suckling routine demonstrated estrus and ovulated sooner after parturition than the control group during the first year of the study. However, this difference was not observed in the second year of the experiment.
• There was no significant difference in the plasma progesterone concentrations between the treated mares and the control group – both remained less than 1 ng/ml from birth to ovulation.
• The conception rates of mares were not significantly impacted by the treatment. Nevertheless, two mares, which had records of failing to have estrus while nursing a foal, were able to breed and ovulate; one of them also conceived while under the restricted suckling treatment.

Implications on Foal Growth

• The study showed that the treatment had no observable effects on the variables measured in foals, thereby suggesting that the growth and development of the foals remained unhindered by the restrictive suckling regimen.

Conclusion

• The results of this research reveal that a restrictive suckling regimen can potentially expedite the onset of estrus and ovulation in Quarter Horse mares after giving birth without significantly affecting their ability to conceive.
• Furthermore, the regimen doesn’t appear to have negative impacts on the growth and development of their offspring.