Comparison of methods to detect gastrointestinal parasites in llamas and alpacas.
OBJECTIVE
To compare relative sensitivity and overall yields of various methods of fecal examination for gastrointestinal parasites in llamas and alpacas.


METHODS
Prospective study.


METHODS
Fecal samples from 42 alpacas and 62 llamas.


METHODS
Fecal samples were analyzed via direct smear, a modified McMaster technique with sucrose solution or saturated saline (approx 36% NaCl) solution, and a centrifugation-flotation procedure. McMaster flotation chambers were examined 15 and 60 minutes after loading. Centrifugation-flotation samples were examined after 10 and 60 minutes of flotation. The proportions of samples with positive results and concentrations of parasites were compared among methods.


RESULTS
The centrifugation-flotation technique yielded more positive results than other methods for all parasites except small coccidia. Longer flotation time increased the proportion of positive results and parasite concentrations for all parasites except Nematodirus spp. Longer time in the McMaster chamber made little difference. By use of the modified McMaster technique, sucrose solution yielded more positive results for Trichuris spp, Eimeria macusaniensis, and strongyles, whereas saline solution yielded more positive results for Nematodirus spp and small coccidia. The saline solution McMaster test yielded more positive results for small coccidia than did most other methods, and the sucrose McMaster technique yielded more positive results for Trichuris spp.


CONCLUSIONS
The centrifugation-flotation technique appeared to offer clear advantages in detecting infection with E macusaniensis, Trichuris spp, Nematodirus spp, and capillarids. The saline McMaster technique appeared to offer an advantage in detecting small coccidia.
Cebra
Christopher K
CK
Department of Clinical Sciences, College of Veterinary Medicine, Oregon State University, Corvallis, OR 97331-4802, USA.
Stang
Bernadette V
BV
D000818:Animals; D002161:Camelids, New World / Q000469:parasitology*; D005243:Feces / Q000469:parasitology*; D005260:Female; D007411:Intestinal Diseases, Parasitic / Q000175:diagnosis / Q000662:veterinary*; D008297:Male; D033661:Oocysts; D010270:Parasite Egg Count / Q000379:methods / Q000592:standards / Q000662:veterinary*; D010273:Parasitic Diseases, Animal / Q000175:diagnosis*; D012680:Sensitivity and Specificity