Which identification method allows for tracking of swine across multiple ownerships?

The identification method that allows for the effective tracking of swine across multiple ownerships is universal ear notching. This system provides a standardized way to mark animals so that they can be easily identified regardless of changes in ownership. Each notch has a specific meaning based on its location and configuration, allowing for a unique identification for each animal.

Universal ear notching is recognized and used by various agricultural and livestock organizations, which facilitates tracking for breeding, health management, and regulatory purposes. This method ensures consistency and clarity in identifying animals, making it easier for producers, buyers, and regulators to trace an animal's ownership history and health records.

On the other hand, branding may not provide the detailed individual identification necessary for tracking ownership since it often includes a less specific mark that can represent a producer or farm rather than an individual animal's history. Color coding lacks the precision needed for long-term tracking as it can vary widely and may not be universally recognizable. Microchipping, while effective for individual identification, may not be as practical in large-scale agricultural settings compared to the efficiency and established use of universal ear notching.