A Simulated Tumor for Teaching Principles of Surgical Oncology for Biopsy and Excision of Skin and Subcutaneous Masses to Veterinary Students.

Tumors of the skin and subcutaneous tissues are commonly encountered in primary care practice. The most common of these tumors are mast cell tumors and soft tissue sarcomas, for which the primary treatment is most often surgical excision. Understanding surgical margins, particularly the deep fascial plane, can be difficult for veterinary students. Current techniques to teach these concepts typically rely on cadaver-based laboratories, which require simulated tumors to improve the realism of the laboratory. Tumors can be difficult to replicate in cadaver laboratories; thus a new technique for a simulated tumor was developed. A gelatin-based simulated tumor was injected into the subcutaneous space in two different sites in canine cadavers. Students then practiced incisional biopsy and wide excision of a subcutaneous mass. Students were able to appropriately perform both techniques using the simulated tumors. When the deep margin was not clean on the wide excision, students were able to understand the error by identifying the simulated tumor, reinforcing the concept of obtaining an appropriate deep fascial plane. In summary, this gelatin-based simulated tumor technique was cost-effective, easy to perform, and effective for the teaching laboratory.

Clinical tolerance of dexamethasone in New Zealand white rabbits.

Rabbits have been a popular pet and research species world-wide. In many clinical and research situations, controlling inflammation is necessary for the health of these animals. One of the first drugs commonly employed in veterinary medicine to suppress inflammatory responses is corticosteroids. Unfortunately, steroid use in rabbits is not universally accepted as they are perceived, based on their potent immunosuppressant activity, to negatively impact quality of life. This is may be due, in part, to the lack of well-developed dosing protocols in these animals. This study evaluated the impact of a 5-day IM dexamethasone (Dex, 0.5 mg/kg) protocol on the immunity and clinical health of the New Zealand rabbit. Through two experiments separated by a 10-day washout period, experiment 1 comprised 5-days of dosing with bleedings on day 0, 3, 5 and 7, where experiment 2 consisted of 5-days of dosing with bleedings on day 0, 3 and 5. Animals were monitored twice daily for changes in clinical health. Hematology, T cell subset phenotype, leukocyte cell cycle, histopathology, phagocytosis and oxidative formation were evaluated. Consistent with other species, 5-day dosing with Dex suppressed leukocytes, in particular the T cells (p ≤ 0.003). Interestingly, rabbits failed to show any adverse clinical signs throughout the entire study. This would imply that a 5-day IM Dex (0.5 mg/kg) dosing protocol is well tolerated by New Zealand white rabbits and could be used in rabbits suffering from inflammatory conditions or disease as long as the animal's immune status is closely monitored.