The impact of tail tip amputation and ink tattoo on C57BL/6JBomTac mice.
Genetic material for polymerase chain reaction (PCR) and Southern blot analysis on transgenic mice is normally obtained by tail biopsy. Additionally, it may be necessary to tattoo the mice, as it is essential to have a good and permanent identification. The aim of this study was to evaluate the effects of amputating the tip of the tail to obtain a biopsy for genetic analysis and of ink tattooing on welfare in C57BL/6J mice, a strain often used as genetic background for transgenes. The behaviour of the animals, fluctuating asymmetry (FA, a measure of developmental instability) and the level of restitution in the remaining part of the tail were evaluated and used for an assessment of the impact of these procedures on the welfare of the animals. One group of mice was marked by tail tattooing at various ages. Another group of mice were tail amputated at 12 or 20 days of age. Body weight and FA were followed, and at the end of the experiment, the level of fear/anxiety was assessed using a light-dark box. In the group of tail-amputated animals observation of climbing behaviour and a beam walking test for balance was performed. Seven weeks after tail amputation, the animals were euthanized. The remaining part of the tail was evaluated histopathologically. Body weight, behaviour in the light-dark box and balance test results were not influenced by tail amputation or tattooing. FA was only transiently increased by tattooing. Climbing behaviour was reduced just after tail amputation at 20 days of age. No signs of neuromas were found in the amputated tails, but seven weeks after amputation a significant number of mice did not have fully regenerated glandular tissue and hair follicles in the tail. It is concluded that both tail amputation and tail tattooing seem to have minor short-term negative effects on welfare and that the tissues on the tail probably do not regenerate fully after amputation.
Sørensen
Dorte Bratbo
DB
Centre for Bioethics and Risk Assessment, Division of Laboratory Animal Science, Department of Veterinary Pathobiology, Royal Veterinary and Agricultural University, Groennegaardsvej 15, DK-1870 Frederiksberg C, Denmark. dobj@kvl.dk
Stub
Charlotte
C
Jensen
Henrik Elvang
HE
Ritskes-Hoitinga
Merel
M
Hjorth
Peter
P
Ottesen
Jan Lund
JL
Hansen
Axel Kornerup
AK
D000671:Amputation, Surgical; D000827:Animal Welfare; D000818:Animals; D001706:Biopsy / Q000662:veterinary; D051379:Mice; D008810:Mice, Inbred C57BL / Q000235:genetics / Q000254:growth & development / Q000523:psychology; D008822:Mice, Transgenic; D013623:Tail / Q000473:pathology / Q000601:surgery*; D013653:Tattooing