1 - Diagnostics

swallowed objects of animals that may look like parasite forms

pseudoparasites

Example of pseudoparasites

plant hairs

grain mites

pollen grains

mold spores

Parasite eggs or cysts from one species found in the feces of another scavenger or predator host due to coprophagy

spurious parasite

consequences of old fecal samples

dehydrated

difficult suspension

undergo development or disintegration not useful for diagnostic

recommended amount of dog cat feces collected

1-2 g if solid

4-6 g if diarrheic

amount of pig ruminants feces to collect

4-10 g routine

20-40gT for fecal or larval culture

transport or preservation liquid for fecal samples for storage

10% formalin

95-100% ethanol: sample (1:1 or 1:2) for nucleic acid extraction

this keeps samples in good condition for at most 48 hrs

refrigeration

3 methods of fecal exam

Simple fecal smear

Qualitative microscopic concentration (sedimentation-decantation/flotation)

Quantitative (Stoll ova counting technique, McMaster Egg Counting Technique)

should be used only with small available samples, lack of equipment or time does not permit use of more accurate techniques

simple fecar smear

in flotation technique, what is the idea for specific gravity

SG of the suspension liquid must be higher than the parasite forms but less than the fecal debris to allow the parasite forms to rise to the top by gravity that can be hastened by centrifugation

example of heavy solutions that can be used as flotation liquid

sodium chloride

sucrose

glycerine

zinc sulfate

zinc acetate

sodium nitrate

sodium acetate

magnesium sulfate

modified fluke egg technique is a type of what qualitative technique

sedimentation-decantation method with surfactant

difference in the solution used for the sedimentation-decantation method with and w/o surfactant

without surfactant - only uses 1% saline

with surfactant - solution = liquid detergent, tap water, and 1% aluminum potassium sulfate

2 types of flotation technique

sugar flotation technique (Sheather’s technique)

Willi’s Brine Flotation Technique

to what organism is willi’s brine flotation technique not useful

protozoan cysts

Schistosoma eggs

Fasciola eggs (too big to float)

what is this instrument and its use

McMaster slide for McMaster Egg Counting Technique (Quantitative fecal exam)

identify the apparatus and its use

Baermann apparatus for larval recovery

Modified Knott’s Method for microfilarial (Heartworm) concentration uses what type of liquid and stain

2% formalin

Methylene Blue Stain

Delafield’s Hematoxylin

Giemsa’s stain