Technique Of Dissection And Extracting Organs Of Laboratory Animals. Message 3 − Hamster

The third message from the series of articles on the methodology of necropsy and extraction organs of laboratory animals, describing in detail and illustrating the technique of sequential and complete autopsy and extraction of organs of laboratory hamsters. Among laboratory animals, hamsters occupy a special place due to the presence of large cheek pouches in their digestive tract. A large area of the mucous membrane lining the cheek pouches from the inside, allows to visually demonstrate and explore the local irritant effect of orally dispersible dosage forms (lozenges), which can easily be placed in the cavity of the cheek pouches. This article demonstrates the procedure for laboratory hamster necropsy. It describes the process of preparing an animal for an necropsy, conducting a primary examination of a corpse after euthanasia for the presence of external changes and injuries, fixing the corpse on the dissecting table, opening and examining the internal cavities of the body, as well as studying the surface lymph nodes. Methods for the extraction of organs of the oral cavity (including the extraction of the tongue, pharynx and cheek pouches along with the adjacent salivary glands), all organs of the thoracic, abdominal, and pelvic cavities are described and illustrated. The topographic location of some organs of the thoracic, abdominal and pelvic cavities is illustrated. Described two methods to extract the brain, along with olfactory bulbs, the method of separating the preparations of the chest bone for histological examination of the bone marrow and maxilla for histological examination of the nasal cavities. The procedure for preparing the spinal cord for fixation in formalin without removing it from the spinal canal is described. Described the extraction of the eyes together with the lacrimal gland and eyelids, the extraction of the muscles and the peripheral nerves adjacent to them. The methods of extraction and the sequence of actions performed, described in this article, minimize the damage to extracted organs, prevent their contamination in order to prevent the occurrence of certain artifacts detected during subsequent histological examination. Conclusions are presented at the end of the article.