A leukocyte identified as an eosinophil with rod-shaped granules in the cytoplasm most likely comes from which species?

A leukocyte identified as an eosinophil with rod-shaped granules in the cytoplasm most likely comes from which species?

• A. Dog
• B. Horse
• C. Cat
• D. Cow

Answer: (C)

In this context, eosinophil granule shape varies by species, and the rod-shaped cytoplasmic granules are a characteristic feature seen in feline eosinophils. When you observe a leukocyte that is an eosinophil with rod-like granules, the specimen most likely comes from a cat. Dogs typically have more standard, rounded eosinophil granules, while horses and cows show different granule patterns that don’t emphasize these rod-shaped inclusions. This morphological cue helps identify the species origin based on typical cytologic appearance.

In this context, eosinophil granule shape varies by species, and the rod-shaped cytoplasmic granules are a characteristic feature seen in feline eosinophils. When you observe a leukocyte that is an eosinophil with rod-like granules, the specimen most likely comes from a cat. Dogs typically have more standard, rounded eosinophil granules, while horses and cows show different granule patterns that don’t emphasize these rod-shaped inclusions. This morphological cue helps identify the species origin based on typical cytologic appearance.