Thromb Haemost 2008; 99(05): 956-962
DOI: 10.1160/TH07-12-0738
Animal Models
Schattauer GmbH

Automated registration of tail bleeding in rats

Peter B. Johansen
1   Haemostasis Pharmacology, Novo Nordisk A/S, Maaloev, Denmark
,
Lars Henriksen
2   Videometer A/S, Hoersholm, Denmark
,
Per R. Andresen
3   Finished Products, NNE Pharmaplan, Soeborg, Denmark
,
Brian Lauritzen
1   Haemostasis Pharmacology, Novo Nordisk A/S, Maaloev, Denmark
,
Kåre L. Jensen
2   Videometer A/S, Hoersholm, Denmark
,
Trine N. Juhl
4   Biostatistics, Novo Nordisk A/S, Maaloev, Denmark
,
Mikael Tranholm
1   Haemostasis Pharmacology, Novo Nordisk A/S, Maaloev, Denmark
› Author Affiliations
Further Information

Publication History

Received 14 December 2007

Accepted after minor revision 26 February 2008

Publication Date:
30 November 2017 (online)

Summary

An automated system for registration of tail bleeding in rats using a camera and a user-designed PC-based software program has been developed. The live and processed images are displayed on the screen and are exported together with a text file for later statistical processing of the data allowing calculation of e.g. number of bleeding episodes, bleeding times and bleeding areas. Proof-of-principle was achieved when the camera captured the blood stream after infusion of rat whole blood into saline. Suitability was assessed by recording of bleeding profiles in heparintreated rats, demonstrating that the system was able to capture on/off bleedings and that the data transfer and analysis were conducted successfully. Then, bleeding profiles were visually recorded by two independent observers simultaneously with the automated recordings after tail transection in untreated rats. Linear relationships were found in the number of bleedings, demonstrating, however, a statistically significant difference in the recording of bleeding episodes between observers. Also, the bleeding time was longer for visual compared to automated recording. No correlation was found between blood loss and bleeding time in untreated rats, but in heparinized rats a correlation was suggested. Finally, the blood loss correlated with the automated recording of bleeding area. In conclusion, the automated system has proven suitable for replacing visual recordings of tail bleedings in rats. Inter-observer differences can be eliminated, monotonous repetitive work avoided, and a higher through-put of animals in less time achieved. The automated system will lead to an increased understanding of the nature of bleeding following tail transection in different rodent models.

 
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