The physical size of gestating sows

Area of Science:

• Animal Science
• Agricultural Engineering

Background:

• Understanding the physical dimensions of gestating sows is crucial for optimizing housing and ensuring animal welfare in commercial swine production.
• Variations in sow size can be influenced by genetics, parity, and management practices, necessitating accurate data for facility design.

Purpose of the Study:

• To determine the physical dimensions of gestating sows in commercial settings.
• To model changes in sow body size relative to parity, body weight, and gestation stage.
• To assess farm-to-farm variation in sow dimensions within a standardized production system.

Main Methods:

• A total of 296 gestating sows from five commercial farms were assessed.
• Measurements included body weight, backfat thickness (ultrasound), body length, height, width, and depth.
• Regression analyses were performed to model sow dimensions based on parity, body weight, and gestation stage.

Main Results:

• Sow body dimensions significantly increased with parity (up to Parity 6) and advancing gestation.
• Genetically different sows exhibited significant variations in body length, width, height, and depth.
• Even with identical feed and management, sows of the same genotype differed in dimensions across different farms.

Conclusions:

• Stall width should be at least 72.4 cm to accommodate the majority of gestating sows.
• Current stall sizes and farm floor space may be inadequate to meet animal welfare recommendations for pregnant sows.
• Data and models derived can guide the design of appropriate stall sizes and farm layouts for improved sow welfare.