Technical note: Evaluation of the official identification system for pigs for sale in New South Wales.

A study was undertaken at 2 saleyard (1 domestic, DS, and 1 export, ES) and 2 abattoir (1 domestic, DA, and 1 export, EA) locations in New South Wales, Australia, to assess the compliance (presence) and readability of body tattoos used to identify individual pigs presented for sale or slaughter. Each location was visited on 3 trading or slaughter days, and tattoo presence and readability of porkers (25 to 60 kg of BW), baconers (60 to 90 kg of BW), backfatters (>90 kg of BW but not for breeding), and breeders were recorded. A total of 4,655 pigs were inspected, including 158 DS, 1,599 ES, 1,257 DA, and 1,641 EA. Tattoo performance at the saleyards was influenced by producer (P < 0.05). Average brand presence at the DS (93.0%) did not differ (P = 0.28) from ES (74.2%). Tattoo compliance ranged from 88.3 to 100% of pigs across pig classes (P > 0.05) at DS. At the ES, tattoo compliance among baconers, backfatters, and breeding stock ranged from 82.4 to 88.3% and was greater (P < 0.05) than that of porkers (70.3%). Average readability was 85.4% at ES and 77.6% at DS (P > 0.05). Tattoo compliance differed (P < 0.05) between abattoirs (98.7% at DA and 92.6% at EA). Readability was greater (P < 0.05) at the EA (80.1%) than at the DA (72.0%). Final performance, as readable brands among animals sold or slaughtered, of the official tattoo system was similar between locations and ranged from 63 to 74%. Our results suggest that current compliance and readability of tattoos would compromise traceback to the farm of origin in the event of an emergency animal disease outbreak. Education activities on legislation requirements and tattoo procedure would likely increase compliance and performance of the system.