standardization of records keeping in indian zoos - Central Zoo ...
standardization of records keeping in indian zoos - Central Zoo ...
standardization of records keeping in indian zoos - Central Zoo ...
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ensure even contact (uneven contact results <strong>in</strong> distorted, broken marks). Application<br />
time varies greatly among species (Table 5.1). Excessive application time kills the<br />
hair follicles rather than just the melanocytes, and the mark becomes a scar that may<br />
or may not be legible. Insufficient contact time results <strong>in</strong> a patchy mark (if any).<br />
Immediately after the <strong>in</strong>strument is removed, the affected sk<strong>in</strong> appears frozen. As the<br />
tissue thaws, the mark fades and a reddened swell<strong>in</strong>g appears. This rema<strong>in</strong>s for 1 to 2<br />
days, after which a scruffy, blistered mark develops. After about 3 weeks the hair and<br />
superficial epidermis are shed, leav<strong>in</strong>g a bare mark. Depend<strong>in</strong>g on the hair growth<br />
cycle <strong>of</strong> the animal, white hair should appear after 1-3 months.<br />
The major disadvantages <strong>of</strong> freeze mark<strong>in</strong>g are as follows:<br />
I. Comb<strong>in</strong>ations <strong>of</strong> proper refrigerant and application time are not yet well<br />
established for a broad range <strong>of</strong> species.<br />
II. The animal must be restra<strong>in</strong>ed for the duration <strong>of</strong> the contact time. A good mark<br />
depends upon proper restra<strong>in</strong>t.<br />
III. The equipment necessary for conta<strong>in</strong><strong>in</strong>g the refrigerant is cumbersome.<br />
IV. Commercially marketed mark<strong>in</strong>g <strong>in</strong>struments <strong>of</strong>ten make marks that are too large<br />
to be <strong>in</strong>conspicuous <strong>in</strong> a zoo.<br />
Freeze mark<strong>in</strong>g has the potential <strong>of</strong> meet<strong>in</strong>g many <strong>of</strong> our ideal mark<strong>in</strong>g method<br />
criteria. It is permanent, can be legible at a distance, and is thought to be pa<strong>in</strong>less; the<br />
rapid freez<strong>in</strong>g <strong>of</strong> the sk<strong>in</strong> acts as a local anaesthetic 9Farrell and Johnston 1973) and<br />
<strong>in</strong>activates local nerve end<strong>in</strong>gs for about 4 weeks (Farrell, Hostelter and Johnson<br />
1978). The dry ice- alcohol and Freon refrigerants are <strong>in</strong>expensive.<br />
Refrigerant Animal Duration Reference<br />
Dry ice and African elephant 2 x 2 m<strong>in</strong>s Pienaar 1970<br />
alcohol(-70o<br />
C) Cow (adult) 30 secs Farrell, Kroger and W<strong>in</strong>ward 1966<br />
Dairy cow 30 secs<br />
(>18mths)<br />
Beef cow 35 secs<br />
(>18 mths)<br />
Dairy cow 25 secs<br />
9-18 mths<br />
Beef cow 30 secs<br />
9-18 mths<br />
Dairy cow 20 secs<br />
(4-8 mths)<br />
Beef cow 25secs<br />
(4-8 mths)<br />
Dairy cow 15 secs<br />
(2-3 mths)<br />
Beef cow 20 secs<br />
(2-3 mths)<br />
Dairy cow 10 secs<br />
(