grasping the tick as close to your skin as possible and using slow, steady traction to pull
their mouthparts from the bite wound.
(3) Place the drag on the ground and place a block of dry ice (2 to 3 inches
on a side) on an inverted, disposable pie tin in the center of the drag. Collect ticks as
they crawl across the drag or next to the dry ice. The dry ice should be wrapped in
paper to avoid damaging the tick specimens.
3-7.
COLLECTION OF ARTHROPOD ECTOPARASITES
a. Trapping. A reliable ectoparasite index is obtainable through rodent trapping
and subsequent combing of the rodent. Ectoparasites wiII only remain on a Iive, warm
host; therefore, the rodents must be caught in a live trap. When trapped, the rodent,
stiII in the trap, is put into a large box or paper bag that contains wads of gauze or
cotton balls that are soaked in chloroform strong enough to stun the animal so it can be
handled (see figure 3-7). The rodent is then transferred to a plastic bag into which
another wad of chloroformed material is added. This time the rodent is left in the bag
long enough so that both it and its ectoparasites are killed. In order for the dead
ectoparasites to falloff, the rodent must be combed, washed with detergent, or both.
Figure 3-7. Trapped rodent being put into correctly labeled paper bag.
(1) Combing. The combing procedure is carried out whiIe wearing rubber
gloves. The rodent is held over a large white enamel pan in order to catch the
ectoparasites as they fall from the animal. Use a double-sided, fine-tooth comb to
remove ectoparasites from the fur. First, comb the rodent from head to taiI to remove
ectoparasites near the surface. Then, comb the animal from tail to head against the
grain of the fur to remove deep-seated ectoparasites. After the rodent is completely
combed, the fur is rubbed with the fingers to make sure all the ectoparasites are
detached. The plastic bag is then checked carefully for any ectoparasites that have
fallen from the rodent during the kiIIing process. Individual ectoparasites are removed
from the pan by use of a camel's hair brush, placed in vials of alcohol, and labeled.
(2) Washing. Another method of collecting ectoparasites from dead rodents
is by washing the rodents. The rodent is captured and killed in the manner previously
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