Pathomorphological Diagnostics Of Lungs At Various Methods Of Euthanasia Of Laboratory Animals

DOI: 10.29296/2618723X-2018-03-05

E. Belyaeva(1), A. Rybakova(1), Ya. Guschin(1), D. Vaganova(1), K. Koptyaeva(1), A. Muzhikyan(1), M. Makarova(1), V. Makarov(2) 1-JSC «Research-and-manufacturing company «Houm оf Pharmacy», 188663, Russia, Leningradskiy region, Vsevolozhskiy district, Kuzmolovskiy, st. Zavodskaya, 3, b. 245; 2-CJSC «St. Petersburg Pharmaceutical Institute», 188663, Russia, Leningradskiy region, Vsevolozhskiy district, Kuzmolovskiy, b. 245 Е-mail: [email protected]

Keywords: euthanasia anesthetics laboratory animals pathomorphological changes lungs

For citation:

Belyaeva E., Rybakova A., Guschin Ya., Vaganova D., Koptyaeva K., Muzhikyan A., Makarova M., Makarov V. Pathomorphological Diagnostics Of Lungs At Various Methods Of Euthanasia Of Laboratory Animals. Laboratory Animals for Science. 2018; 3.


It is known that carbon dioxide and anesthetics used for euthanasia laboratory animals can lead to the appearance of artifacts, the presence of which makes pathomorphological diagnosis difficult. The purpose of this study was to identify pathomorphological changes in the respiratory organs associated with the using of the most common methods of euthanasia. The study was performed on male and female rats, mice, ferrets and rabbits. In all animal species, various doses and concentrations of carbon dioxide, Vetofol, and combinations of Zoletil and Xyla were used in the intravenous and intraperitoneal route of administration.After confirming the death of the animal, extraction of the lung was carried out, followed by fixation in 10% formalin, histological extraction, standard histological wiring, sectioning and staining with haematoxylin and eosin. Within the use of each method of euthanasia were found macroscopic and histological signs of edema, atelectasis and emphysema of the lungs, foci of hemorrhages, which were found in different degrees of severity in all of the studied animals. The degree of manifestation of the detected changes was greatly influenced by the way the drugs were administered.Less prominent pathological changes in the respiratory organs were identified by intravenous administration of a combination of drugs Zoletil and Xyla, while the intraperitoneal administration of the same drugs changes reached maximum severity.The obtained results give an opportunity to offer practical advice on the choice of the method of euthanasia and dosage drugs during the pathomorphological diagnostics respiratory organs of laboratory animals as part of the pre-clinical studies.


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