Pad-plate diffusion assay for virginiamycin in mash-type feeds.

Area of Science:

• Animal Nutrition
• Analytical Chemistry
• Feed Science

Background:

• Accurate quantification of virginiamycin is crucial for ensuring animal feed quality and efficacy.
• Existing methods for virginiamycin analysis in mash-type feeds can be complex and require compensatory curves.
• Fat content in feed can interfere with analytical procedures, necessitating effective removal techniques.

Purpose of the Study:

• To develop and validate a simplified assay procedure for determining virginiamycin content in mash-type feeds.
• To eliminate the need for compensatory curves based on feed composition.
• To provide a simple, accurate, and precise method for virginiamycin analysis.

Main Methods:

• A rapid petroleum ether wash was employed to remove fat interferences.
• Citric acid and acetone extractions were utilized for sample preparation.
• The pad-plate diffusion system was used for the quantitative determination of virginiamycin.

Main Results:

• The developed assay procedure demonstrated high recovery rates, averaging 89.3% (CV 5.76%) for feeds with 11.0 µg/g virginiamycin.
• Recoveries averaged 89.9% (CV 9.92%) for feeds containing 13.2 µg/g virginiamycin.
• The method effectively removed fat interferences and eliminated the need for compensatory curves.

Conclusions:

• The new assay procedure is simple, accurate, and precise for quantifying virginiamycin in mash-type feeds.
• This method simplifies the analysis of virginiamycin in animal feed, improving efficiency.
• The validated procedure is suitable for routine quality control of animal feed containing virginiamycin.