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Published on: October 2, 2018
Ovarian activity and uterus organometry in delayed puberty gilts
Ivan Stancic1, Blagoje Stancic, Aleksandar Bozic
1University of Novi Sad, Faculty of Agriculture, Novi Sad, Republic of Serbia. dr.ivan.stancic@gmail.com
Theriogenology
|July 2, 2011
Summary
Approximately 30% of gilts are culled for delayed estrus. This study found most culled gilts exhibit cyclic ovarian activity, suggesting estrus detection methods may be inadequate for identifying reproductive readiness in swine.
Area of Science:
- Veterinary Medicine
- Animal Reproduction
- Swine Husbandry
Background:
- Prolonged pre-insemination anoestrus leads to culling in approximately 30% of gilts.
- Estrus detection is critical for timely insemination in commercial swine breeding operations.
Purpose of the Study:
- To determine if gilts culled for delayed estrus exhibit cyclic ovarian activity.
- To investigate potential causes for the discrepancy between ovarian activity and observed estrus in gilts.
Main Methods:
- Examination of reproductive organs from 175 culled gilts (aged >8 months) lacking external estrus signs.
- Assessment of ovarian maturity (follicles, corpora hemorrhagica/lutea/albicans), uterine weight, and uterine horn length.
Main Results:
- Functional ovaries indicating cyclic activity were found in 107 (61.1%) of the examined gilts.
- 62 gilts showed one puberty ovarian cycle, and 45 showed two.
- No significant pathomorphological changes were observed that would explain the prolonged anoestrus.
Conclusions:
- The majority of gilts culled for delayed estrus do achieve cyclic ovarian activity.
- Inadequate estrus detection technology is likely the primary reason for culling these reproductively capable gilts.
- Improving estrus detection methods could reduce unnecessary gilt culling in swine production.
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