Exchange program opens doors for Chilean student veterinary researchers | Virginia Tech News

Fighting stubborn ear infections in dogs

For Valdés, the journey to Virginia Tech culminated her veterinary education with hands-on research experience. Working in the laboratory of Jessica Gilbertie, associate professor of microbiology, Valdés investigated why some dog ear infections keep returning despite treatment. 

“About 25 percent of dogs with ear infections experience recurrence within two years,” Valdés said during her final presentation. “This is often because the bacteria form these protective biofilms. Two common bacteria in dog ear infections — Pseudomonas aeruginosa and Staphylococcus pseudintermedius — can work together to create especially strong biofilms that resist standard treatments.”   

Her research tested eight antimicrobial therapies against clinical isolates from canine ear infections. Pseudomonas aeruginosa is particularly concerning as it’s a multidrug-resistant bacterium that can cause serious infections in various animals and humans. The findings showed that even the most effective treatment, Mometax, only reduced Pseudomonas biofilm by 36 percent, highlighting the need for better treatment approaches.  

“One of the skills I gained was designing a protocol from scratch — not just following steps but understanding all the elements that go into a research project,” said Valdés. “I also learned that science involves failure and resilience. When I failed, I got frustrated, but I learned that’s part of the process — trying again and learning from mistakes.”   

Her experience at the veterinary college confirmed her passion for research. “I already had this research seed in my brain, but this experience allowed me to water that seed. Now, I want to continue on this academic path to see if my sprout can grow into a tree.”   

Improving cancer diagnosis in dogs

While Valdés was cultivating bacteria, Guevara was examining cancer cells with Natalia Strandberg, clinical assistant professor in the clinical pathology department. 

“Canine lymphoma is one of the most commonly diagnosed cancers in dogs,” Guevara said. “While most cases involve B-cells [a type of white blood cell], there are many subtypes with different behaviors and outcomes. Treating all lymphomas as if they’re the same could lead to inappropriate treatments and poorer outcomes for some dogs.” 

Her study analyzed 34 cases of canine lymphoma, comparing diagnoses made from examining cells under a microscope with more advanced testing methods. The results showed that the simpler cell examination method correctly identified the lymphoma type, whether B-cell or T-cell, in 29 of 31 cases — a promising finding that supports using needle sampling as an effective initial diagnostic approach.   

“This needle sampling technique is less expensive and more practical than surgical biopsies,” Guevara said. “Our findings suggest that following a specific examination protocol helps veterinarians consistently identify lymphoma types, regardless of their experience level.” 

Beyond her research project, Guevara participated in daily clinical pathology practice and received intensive training in the Cytopathology Reading Room.  

“The level of veterinary medicine here is impressive,” she said. “The professionals, especially the clinical pathologists, are amazing. I’ve learned so much.”