standardization of records keeping in indian zoos - Central Zoo ...

glue helps to ensure that the PIT tag does not become ejected before the wound heals
(Wright 2001b).
Complications with PIT tags which have been noted include: migration of
transponders if applied subcutaneously or internally, which may make them more
difficult to read; breakage of the tags; and loss of signals (Wright 2001b).
6.5 Freeze Branding
Freeze branding was first used as a technique for individually marking anurans in
1976 by Daugherty.
Method:
.
Picture 26: Freeze branding of Xenopus laevis
Pieces of copper wire, bent into the shape of numbers, are placed into liquid nitrogen
until boiling stops. The brand is momentarily placed for 1.5 seconds on the ventral
surface of an X. laevis which has been patted dry with tissue.
Picture27: Once branded animals are easily identified by number. The brands will be clearly visible
within 24 hrs. This individual (089) was branded 2 years previously.
DISCUSSION
Hot and freeze branding in amphibians are other invasive methods of marking
but they are not recommended, as brand marks in amphibians may not be visible after
a few months. Though described as convenient and the least expensive technique for
marking amphibians (Donnelly et. al. 1994) recent studies has shown a number of
negative effects of toe clipping. One of the disadvantages is that marks are not
permanent since toes regenerate. Clarke (1972) reported a possible negative effect on
survival using toe clipping in Bufo woodhousei fowleri. Underhill, cited in Daugherty
(1976), noted a loss of weight in toe-clipped Rana pipiens. For tagging amphibians
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