Screening a Great Help 
Wherever it is feasible to screen feces to examine them for para¬ 
sites, screening is a great help. The feces of the dog, cat and pig 
may be broken up in water and screened without difficulty. Sheep 
and goat feces are much more difficult to handle in this way, though 
they can be screened to advantage in looking for parasites. Cow 
manure is easily screened, but its bulk makes the examination of the 
manure for one day a task. Horse manure is too coarse to screen 
successfully in the amounts passed in one day and must be examined 
by being carefully picked apart by hand. Wherever screens may 
be used, the nature of the screen to be used depends on circumstances. 
Where few fecal examinations are made and little apparatus 
is available, a piece of cheesecloth may be stretched over hoops or a 
bucket top to make a screen. Where fecal examinations are a routine 
matter, wire screens, such as copper or brass screens, of assorted 
sizes, from 6 to 100 mesh apertures to the inch, are of value. After 
the feces have been broken up thoroughly by soaking in water and 
shaking, they are poured through the screen or screens and each screen 
then put in a glass dish containing water and examined for para¬ 
sites. The material on the screen may be rinsed off into this glass 
dish and examined for worms or other parasites present. 
Examination for Parasite Eggs 
Where parasite eggs are sought for by microscopic examination, 
the simplest technic is the so-called smear method. A bit of feces 
is taken on a match, tooth-pick or stirring rod, rubbed to a uniform 
smear in a little water on a slide, covered with a cover glass and exam¬ 
ined under a microscope. It will afford satisfactory evidence as to 
the presence of parasite eggs provided there are numerous eggs 
present in the feces. For detecting gross infestations this method 
may be entirely satisfactory in some circumstances. It is not a 
delicate method and can not be depended on to detect light infestations. 
Its results become increasingly dependable in proportion to the num¬ 
ber of slides made and examined from a given fecal sample, but the 
length of time involved in examining such preparations makes it 
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