[Implantation of transponders at the bottom of the ear in equines].

The research article discusses the use and effectiveness of transponders, which are small devices used for identifying and tracking animals, when implanted at the ear base of horses. The study found that these devices are easy to handle and cause minimal side effects.

Transponder Implantation

• The study involved the implantation of transponders from two different identification systems on an accurately defined site at the base of the ear of 28 horses.
• The systems evaluated were the Backhome system and the Trovan system. Researchers found the Backhome system easier to handle and less complicated due to its smaller and more manageable size.

Post-implantation Observations

• The study observed minimal side-effects post-implantation. Hemorrhages, or bleeding, occurred after the injection, but they were mild in 17 animals and moderate in four animals.
• Changes at the injection site were limited to minor swelling (in three cases) and slight pain (in six cases).

Performance of the Transponders

• The study noted differences in the “interrogator’s scope” (reading range) of the two transponder systems. The Trovan system had a range of about 5 to 10 cm, while the Backhome system had a range of approximately 15 to 25 cm. The longer range of the Backhome transponder makes it more beneficial.

Pathological Examinations

• All 14 horses that were slaughtered were examined. Researchers found that two transponders had moved considerably from their initial injection sites, approximately 8 to 10 cm.
• The connective tissue surrounding the transponder was transparent and thin in cases where the transponder implantation was 30 days old or less. Beyond this timeframe, the tissue thickness altered.
• Minor inflammatory changes were noted in three cases as slight perivasculitis and in five cases as a collection of single siderophages. No inflammation was determined in the remaining five cases.
• Due to the minor changes and lack of inflammation, researchers concluded that the transponders showed high biocompatibility, meaning they interacted well with the biological tissue without causing adverse effects.