ELECTRONIC IDENTIFICATION CATTLE

The influence of different housing systems on the failure rate of tran sponder implants was examined. TIRIS(TM) or TROVAN(TM) transponder imp lants were inserted at the preferred site, just beneath the triangular cartilage at the base of the ear. A total of 1013 cattle of various b reeds and ages were maintained in different housing systems. The accep tability and application problems associated with the two types of imp lants were recorded. The implants were read at monthly intervals for 1 2 months and failures recorded. The implantation of the TROVAN(TM) tra nponder was simpler to perform, but 1.9% of TIRIS(TM) transponders wer e damaged during the implanting procedure while no damage was incurred on the TROVAN(TM) transponder. The healing process was complete one w eek after application for both products. However, histological examina tion demonstrated a local inflammatory reaction comprising a thin caps ule of connective tissue that produced a well anchored tissue implant. In most cases transponder failure was due to fracture of the glass ca psule. Functional failure occurred over a period of 5 months and was r elated to the age of animals rather than to the housing system. Failur e occurred more frequently (7.05%) in young animals due to the small s ize of the triangular cartilage compared with the size of the transpon der. The removal procedure proved difficult for both products. The stu dy of the leading range revealed that only the larger TIRIS(TM) transp onder is justified for cattle.