Matching ewes with their offspring is a difficult process in large herds. Dr. Reid Redden is a Texas A&M Extension Sheep and Goat Specialist in San Angelo and he indicates matching lambs and their mothers can be a logistical and economic nightmare as it requires time, facilities and added feed cost. Also, the animals are in an unfamiliar environment, which increases stress. He indicates there is the potential to greatly increase the lamb and kid crop by selection of twin born and reared offspring, but most replacement lambs and kids are selected without this information. Traditionally, ranchers wanting to verify parentage would bring females into small areas during the lambing and kidding period to match up offspring with their dams at birth or soon thereafter.
However, some new technologies have been developed to help in the process and these are radio frequency identification (RFID) ear tags and genetic testing. Both dam and offspring must have an RFID tag, and as they travel through a check station in single file, a tag reader matches mother and babies. The extension service in San Angelo tested a unit made in Australia that cost about $3,600, and it functioned well. There are private sector RFID service providers in which ranchers do not have to buy the unit but pay approximately $1 per head for the service.
Genetic testing is also available to determine parentage and requires the rancher to take a small blood sample and place it on a card and send it in to the lab. This test costs about $25 per head and all animals must be tested, but after the first year only lambs would be tested as the parents’ results would already be on file. If you have questions, contact Dr. Redden at firstname.lastname@example.org.