Sampling size methodologies used in pig welfare audits underestimate animal-based measures: a preliminary exploration

Area of Science:

• Animal Welfare Science
• Swine Production Systems
• Auditing and Assessment Methodologies

Background:

• The Common Swine Industry Audit (CSIA) is used to evaluate animal welfare in commercial swine operations.
• Accurate assessment of animal-based measures is crucial for effective welfare monitoring and improvement.

Purpose of the Study:

• To compare the occurrence of animal-based welfare measures identified using the CSIA sampling method versus a total farm inventory (TOTAL) approach.
• To evaluate the accuracy of the CSIA sampling method in representing on-farm welfare conditions.

Main Methods:

• An observational study involving approximately 240,000 pigs across 60 farms.
• Two sampling methods were employed: total farm inventory (TOTAL) and the CSIA sampling method.
• Ten animal-based measures were assessed, and occurrences were compared between the two sampling strategies.

Main Results:

• The CSIA sampling method resulted in fewer recorded occurrences of various welfare issues (e.g., severe lameness, abscesses, wounds) compared to the TOTAL method across sows, nursery, and finisher pigs.
• Observed discrepancies suggest potential underestimation of welfare problems by the CSIA method.

Conclusions:

• The current CSIA sampling method may not accurately estimate the prevalence of animal-based welfare measures at the farm level.
• Further research into alternative sampling methods is recommended to better reflect total farm inventory conditions and improve welfare assessments.