Managing Seasonal Infertility in Sows: Parity and Farm-Specific In-Barn Environmental Predictors of Reproductive...

Area of Science:

• Animal Science
• Reproductive Biology
• Environmental Physiology

Background:

• Seasonal infertility is a significant issue in swine production.
• Environmental conditions and sow parity influence reproductive performance.

Purpose of the Study:

• To identify in-barn heat load (HL), light variability (LV), and parity as predictors of farrowing success (FS) and litter size (LS).
• To analyze these factors in purebred Large White sows under subtropical and tropical Brazilian conditions.

Main Methods:

• Utilized reproductive records from two commercial farms in 2021.
• Recorded in-barn temperature and illuminance using data loggers.
• Analyzed 732 service records using logistic and linear regression models.

Main Results:

• Parity was associated with higher odds of FS and greater LS in the combined analysis.
• Heat load (HL) showed a positive association with litter size (LS) but not farrowing success (FS).
• Light variability (LV) was negatively associated with FS and LS on Farm 2.

Conclusions:

• Sow parity is a strong determinant of reproductive performance in swine.
• In-barn environmental effects on reproductive outcomes are context-dependent and vary by farm.