The technology for electronic identification (ID) of bovines iscurrently available with the advent of passive electronictransponders. At issue is the most appropriate method toattach the electronic ID to the animals. The options include anelectronic button tag in the ear, an implantable electronic chipin the ear base or an electronic bolus placed in the rumen/reticularvia the oesophageal route.• Aseries of experiments which compared different implantationsites for electronic chips found that the most suitable site forimplantation was under the scutellar cartridge of the ear.This sitegave very good retention values and was also a secure site, however,it was not possible to palpate the transponder.• The recovery of injectable transponders post slaughter wasproblematic and as a result due to potential risk of implantabletransponder entering the food chain it was not possible torecommend the injectable (implantable route).• Electronic rumen boluses with a specific density less than 2were rapidly expelled from the rumen, with 100% expulsion byday 56 following placement in the reticulo-rumen.• Rumen boluses with a specific density of 2.75 and greater hadan annual non reading rate of less than 1%, however, the lossrate in adult beef cows was greater than in growing and finishingcattle.The reason for this difference was unclear and may bediet related.• Recovery of boluses at slaughter was undertaken in the offal halland generally the bolus was present in the reticulum and waseasily detected by palpating the reticulum. One hundred percentrecovery was not achieved in practice, various unforseen eventsincluding accidental dislodgment and cutting techniques preventedrecovery.• Abolus dispenser with a long connection will facilitate deliveryof the bolus directly to the calf’s reticulum. • Electronic failure of transponders in the reticulo-rumen was nota problem and read-failure rate was associated with bolusesexpelled from the reticulo-rumen.• There was no differences in read-failure rate (or loss rate)between two commercial boluses which were compared in differentcatgories of cattle.• Electronic button tags from two commercial companies werecompared and it was found that any difference between theelectronic button ear tags was associated with a defective applicatortaggers.• Overall, the animal loss rate for electronic button tags wassomewhat higher than that reported for electronic rumenboluses.
AGRIP End of Project Reports
Teagasc End-of-Project Reports