title: Subcutaneous tissue reaction to polyethylene terephtalate-covered electronic identification transponders in pigs.
abstract: Polyethylene terephtalate-covered identification transponders were injected in 4 week old piglets to examine clinically and histologically the reaction in the surrounding tissue after 4, 7 and 21 days and 6 months. Inflammatory signs at the injection site were clinically noticed from 2 days onwards and gradually decreased after day 3. A second series of inflammatory events occured in some animals around day 7. Swelling was observed thereafter in a few animals. In the pigs slaughtered at day 4, all samples showed a layer of exudate and debris surrounding the transponder. Afterwards a fibrous capsule developed. The mean thickness of reactive tissue decreased significantly (p < 0.01) between days 4 and 7 and days 14 and 21, and remained unchanged between day 21 and 6 months. The mean (+/- s.e.) capsule thickness was 0.32 +/- 0.12 mm after 6 months. It is concluded that PET-covered transponders are encapsulated in fibrous connective tissue within 3 weeks after injection at the base of the ear. After 6 months the capsule around the transponder revealed no or only minor signs of inflammation.
authors: DLO Research Institute for Animal Production, Zeist, The Netherlands.
authors: E
authors: E
authors: Lambooij
authors: P H
authors: PH
authors: de Groot
authors: R F
authors: RF
authors: Molenbeek
authors: E
authors: E
authors: Gruys
mesh_terms: D000823:Animal Identification Systems; D000818:Animals; D003877:Dermatitis, Contact / Q000662:veterinary*; D011093:Polyethylene Terephthalates / Q000009:adverse effects*; D019736:Prostheses and Implants / Q000662:veterinary*; D012867:Skin / Q000473:pathology; D013552:Swine; D013553:Swine Diseases / Q000139:chemically induced*
chemical_list: D011093:Polyethylene Terephthalates