|
Dissection of the
Assassin Bug (Triatoma infestans, Rhodnius prolixus)
Prior to the dissection,
perform an external recognition of the different parts that compose
the insect: head, thorax, and abdomen, and its particularities
(Figs. 1, 2, 3, 4, 5, and 6).
Systems to
observe during dissection
-Dorsal vessel, grease
tissue, spiracle, and tracheas.
-Digestive system:
pharynx, esophagus (stomodeum), stomach (promesenteron), intestine
(postmesenteron), Malpighi tubules (4), rectal ampulla (proctodeum),
rectum.
-Salivating glands (3
pairs), and salivary duct.
-Male genitalia:
testicles, vas deferens, seminal vesicle, accessory glands,
ejaculating duct.
-Female genitalia:
ovaries, oviduct, spermatheca, accessory glands (in R. prolixus),
vagina.
-Nervous system: brain
(optical lobules, ocelli and ocellar nerve, frontal ganglion,
protocerebrum, deutocerebrum, tritocerebrum), ventral nervous chain
(subesophageal ganglion, prothoracic ganglion, posterior ganglion =
mesothoracic ganglion + metathoracic ganglion + abdominal ganglion),
and nerves.
-Cardiac bodies.
Materials
-Paraffin.
-Tweezers with fine
points.
-Dissecting needles
with handles.
-Scalpel with
switchable blade.
-Physiologic solution
for insects (it is convenient to have it ready in a syringe of 1
ml).
-Alcohol 70%.
-Blue metilene.
-Absorbing paper.
Preparation
Put the insects to sleep by placing them inside a freezer for a few
minutes. Melt the paraffin and pour in a Petri dish.
Wait until the paraffin is warm (without it being solid).
Place the insect in the center of the capsule, giving special
attention to covering the neck with paraffin to avoid movements of
the head. Let the paraffin solidify. Fill the capsule
with physiologic solution and begin the dissection.
>>Continue <<Back
<<Back to IPO |
