Another useful method for Physaloptera species egg recovery is sedimentation in water, which is easy to do and recovers heavy eggs. And if enough eggs are present,
direct fecal smears (wet mounts) in saline solution may work, although they are generally considered much less efficient because
of the small sample size. One case study found that direct smears recovered more Physaloptera species eggs than did fecal flotation, but this was directly related to the low specific gravity of the flotation solution
used (sodium nitrate solution at a specific gravity of 1.200).2
In most cases in which no eggs are present in the feces,3 antemortem diagnosis will not be possible except by endoscopy (or gastrotomy). In such cases, it is important to do a thorough
endoscopic examination on a distended stomach, since small, single worms hiding underneath rugal folds may be missed.3 In such cases, using a videoendoscope has been suggested for improving detection of the worms.3
Kevin R. Kazacos, DVM, PhD
Department of Comparative Pathobiology
School of Veterinary Medicine
West Lafayette, IN 47907
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