up a fresh sample of droppings and place on the slide. The
sample must be fresh and soft - a dried sample will not work.
For waxbills, the entire dropping can be used. For finches
with larger droppings, you may only need about half the dropping.
For larger birds, it is best to take a small sample from various
parts of the dropping and analyze them individually on separate
slides. You only need a small amount - 2 or 3 square mm.
finch dropping on the tip of a coverslip
drop or two of saline solution to the sample. Using a toothpick
or similar item, mix the dropping with the saline solution
to get it to dissolve a little. Place the cover slip on top
of the dropping, and press down gently on the center. Slide
the cover slip around a bit on the slide, trying to distribute
the dropping mixture into a very thin layer through which
light can penetrate. Make sure there is no debris, such as
seed hulls or grit, preventing the cover slip from laying
flat on the slide.
dropping and saline solution on the slide. A second
drop of saline was added after the photo.
after the fecal matter and saline
have been thoroughly mixed and the
the slide on the microscope stage and turn the microscope
on. You may want to canvas the slide at 100x first. If you
find something interesting, center it under the lens, then
switch to a higher power to view it more clearly.
microscope's coarse focus to bring the slide contents into
focus. Then use the fine focus adjustment to look through
the different layers of the smear. Note that you will miss
a lot if you do not adjust the fine focus throughout the depth
of the smear. The smear is not so thin that everything can
be seen at one fine focus adjustment.
entire slide consists of plant material and fecal debris (brownish/yellowish
color), you won't be able to see very much. You need to use
a smaller fecal sample and dilute more with saline solution.
Many of the organisms will be apparent in the clear solution
portions of the slide (white background).
microscope camera is one of the extremely cheap ones and takes
grainy, somewhat fuzzy, low-resolution images that leave a
lot to be desired. However, it is good enough to get a general
idea of what each subject looks like. Note that all of the
subjects photographed below were clearly viewed by me at the
magnifications noted. However, the microscope camera severely
crops the field of view, so what you see here is actually
only about a fourth of what can actually be seen through the
material is likely to be abundant in the droppings and is very
easy to recognize. It will consist of tissues with a definite
cellular pattern, and it will not be as transparent through
the light. Plant material frequently is a yellow to brown color.
Birds will ingest feather material when preening and this
material will be expelled in the droppings. I actually identified
a feather plucker in my aviary during a fecal screening when
I found that he had an abnormally high number of feather fragments
in his dropping.
Air bubbles will appear as round objects of varying sizes.
The object has a solid black rim and is pretty much empty
inside. Many first-timers confuse air-bubbles with parasite
eggs. However, once you've seen an air-bubble, you are sure
to recognize it in the future.
Spherical pollen shows up as a golden yellow-brown circle.
They are fairly large compared to normal background material
such as urate crystals. You can usually identify them from
their color, which will be similar to plant material and not
transparent like most organisms of interest. Note that pollen
comes in other shapes, but the only ones I've ever seen have
crystals are small, clear, roughly round (but not necessarily
smooth) circular objects. They frequently have a crystal-like
pattern of striations radiating from the center, making them
look darker than other artifacts. I find urate crystals to
be a nice item to focus on when initially trying to bring
the fecal into view, as yeast and other organisms tend to
show up on the same focal plane.
magnification - Note: the clear circles of equivalent
size to the urate crystals are likely starch granules.
Macroconidia - new 7/18/05
fungal macroconidia appear impressive under the microscope,
according to Dr Danny Brown in Under the Microscope,
they are relatively normal background material and do not
imply a fungal infection. Instead, they result from accidentally
ingesting fungi from the environment.
the time, the things you see under the microscope are pretty
sedentary. However, sometimes you might notice movement. This
can be an indication of protozoal activity, but it can also
be quite normal. The following motion is normal and no cause
In this case, organisms and background material that are on
the same focal plane appear to move in the same direction
and at the same speed, much like objects floating together
down a river. This is most evident when a new slide has just
been created or when you accidentally bump the cover slip,
and it is caused by the saline solution flowing beneath the
cover slip. Once the saline solution settles, this motion
tends to stop.
Brownian motion is what causes the very smallest bacteria
and background material to appear to jitter and move as if
of its own accord in a very random way. In actuality, the
particles are not moving of their own volition (although some
types of bacteria are capable of movement), but instead are
being pushed around by bombarding water molecules. In my very
limited experience, Brownian motion has been limited to the
smallest particles that can be seen at 400x and does not usually
have much affect on larger, heavier particles, like urate
of Budding Yeast and Pseudohyphae (Candida)
Here is an example of a budding yeast organism. Note that
non-budding yeast (single, oval shaped organisms) may also
be present, but there is no way to tell if the non-budding
yeast came from bread yeast ingested by the bird (harmless)
or from the infectious organism, unless the presence of budding
yeast is also found (bread yeast does not bud).
Here you can see some of the yeast forming pseudohyphae. These
images are the very branched, advanced pseudohyphae originally
seen in my bird before beginning treatment.
images were taken after treatment had begun. The pseudohyphae
became sparse, and when I did find them, they were not as
complicated as many of the original organisms.
of Avian Gastric Yeast (Megabacteria) - new 5/14/2005
images were taken from one of my zebra finches. Despite showing
no symptoms, he was infected with Avian Gastric Yeast (AGY),
which I detected while screening my birds for the protozoa
described below. These images came from a dropping in which
a large number of organisms were shed. Subsequent droppings
yielded much fewer organisms. This behavior is typical of
AGY, and is why it is a good idea to keep monitoring a bird
if even only a few AGY organisms are found.
this bird had no symptoms, my masked grassfinch died years
ago after attempted treatment for AGY. That bird had symptoms
identical to Candida (occasionally fluffed, sleeping a lot
when other birds were active, appearing to eat a lot). Avian
Gastric Yeast is sometimes blamed for the condition referred
to as "Going Light." The organism differs from Candida
under the microscope in that there are no budding yeast organisms,
nor are there any branching yeast (pseudohyphae). Avian Gastric
Yeast organisms are clearly detected as long, straight rods
(once thought to be very large bacteria, hence the old name
Megabacteria). While these rods were visible at 100x, the
400x magnification was needed before I could identify them.
prescribed Amphotericin B suspension (.01 cc orally once a
day), the only somewhat effective treatment available. I recommend
using the oral suspension, which is available from your vet,
on an established infection, since I do not believe the water-soluble
version is very effective when the infection has progressed
this far. Amphotericin B is quite toxic, so it should only
be used when indicated.
Amphotericin B suspension is only effective in about half
of the cases. In other cases, you are out of luck. Once cured,
there is a good chance the infection will return, so occasional
screenings might be useful. I have heard that AGY can be transmitted
to young when feeding, so some recommend fostering eggs or
chicks rather than allow them to be reared by an infected
parent. Better still - remove the infected bird from your
of Coccidia Oocysts - new 6/5/2005
is a protozoa that can be detected in a fecal smear via the
presence of oocysts (think of oocysts as being like eggs).
Two different types of coccidia infect birds: Isospora genus
and Eimeria genus. Isospora oocysts clearly have two sporocysts
(masses within the center of the oocyst). Eimeria have four,
but you likely will not be able to distinguish them and they
will appear as one large mass in the center of the oocyst.
You will need to view at 400x in order to detect them.
above were taken from a smear of a newly acquired bird in
quarantine. The bird was completely asymptomatic, so I have
no symptoms to report, although diarrhea and "fluffed
appearance" are frequently described in symptomatic birds.
The genus here is likely Eimeria spp. My microscope camera
did a very poor job depicting this center mass, even when
I used the oil immersion lens at 1000x. However, the top photograph
on page 33 of Under the Microscope by Dr. Danny Brown
is an exact representation of what I saw. I thought perhaps
the first one I found was spherical pollen that had lost its
coloration. When I saw many more throughout the sample, I
knew something was wrong. Luckily, I implement home screening
of all new birds throughout quarantine and was able to detect
the problem before it could be spread to other birds.
of Threadworm Eggs - new 11/16/2005
to my friend Rick, a falconer, I was provided with a poop
sample from a red-tailed hawk. It is very common for wild
hawks to carry worms, so I checked. Sure enough, the poop
sample was filled with tiny threadworm eggs. The eggs were
easily visible, many to a frame at 100x. At 400x, they were
quite large and obvious. Threadworm eggs can be easily identified
based on their shape. They are shaped like long ovals and
have little caps at each end.
of Motile Flagellate Protozoa - new 5/14/2005
protozoa can be detected by observing unusual movement in
the background material (eg, jittering, dancing, spinning
urate crystals), then looking in the area of movement for
the causative organism. To verify that you are not seeing
Brownian motion (described above), use the fine focus adjustment
to carefully focus in the area of movement until you find
the actual organism, which is very nearly transparent, bumping
into background material. If you are lucky, you might see
the flagella, a hair-like structure that will whip out from
the body of the protozoa and cause it to move or spin. You
will need to view at 400x or greater in order to detect the
protozoa. Some protozoal organisms do not survive long outside
the body, so you need to analyze a fresh dropping quickly
in order to detect them.
my microscope camera is of too low quality to get a clear
picture of the organism and because movement is really the
key to spotting it, pictures are useless. Instead, I attempted
to capture a video. The smear used was not the best for viewing
the protozoa, but by the time I had the computer and camera
hooked up and the appropriate video software installed, I
was only able to look at one more smear before losing the
bird. In this (very low quality) video, I have pointed out
the following in this order: what I believe is the organism
moving, then another organism appearing in the same frame,
the flagella whipping out on an organism that has ceased moving
(hard to distinguish in the video), and the background material
being disturbed by the organism (a clue to look for the protozoal
organism to rule out Brownian motion).
THE FORMAT OF YOUR CHOICE:
Flagellate Protozoa - .MPG (6.71 MB)
- .WMV (1.73 MB)
- .RM (2.18 MB)
in the video moves a lot like Trichomonas,
which although usually detected via a crop smear, can also
sometimes be shed in the droppings (according to my vet).
However, the usual symptoms of Trichomonas, including vomiting
and white lesions in the mouth, were not present. Other possibilities
include Giardia, Cochlosoma, and
Hexamita, although in my amateur opinion, it was
not moving in a way consistent with the Hexamita. Fortunately,
the treatment options for most flagellate protozoa are the
same, so identifying the exact type is not a primary concern.
For those interested in differentiating some of the species
(Trichomonas, Giardia, and Hexamita) based on movement, the
DVM website has excellent videos in which the organisms
move freely without impedance from the background material.
society finch died before I could treat it, but protozoa are
very infectious, so all birds needed to be treated and the
aviary disinfected with bleach. Ronidazole (the active ingredient
in Ronivet-S) is frequently used to treat protozoal infections.
I was advised to use this at 4x the recommended dosage (1/8
tsp per 125 ml), but always follow your vet's instructions.
Metronidazole is also used, but it is bad-tasting, and recent
reports show that Giardia is becoming increasingly resistant
to it. After a week of treatment, my vet examined a sample
of my birds and did not see any further evidence of protozoa.
are interested in learning to do your own fecal smears, fecal
floats, or gram stains, I highly recommend the book Under
the Microscope: Microscope Use and Pathogen Identification
in Birds and Reptiles by Dr. Danny Brown. This book can
be purchased from www.avianpublications.com
will teach you about the parts of a microscope and how to
use one (helpful if your microscope does not come with a manual
and you no longer remember what you did in high school science),
as well as how to do a fecal smear, a fecal float, and even
information on doing a gram stain. It is written for aviculturists
and herpetologists, rather than for veterinarians and veterinary
technicians, and is filled with illustrations of both normal
background material and abnormal organisms and parasite eggs
commonly found in bird and reptile droppings.
normal and abnormal findings will take much experience (I
have just started on this journey), but it is helpful to have
a reference to refer to turn to while you work your there.
would like to discuss this topic and share photos and insight
with others interested in the same thing, consider joining
Microscopy Yahoo! Group. This is a new group formed by
individuals interested in exploring this topic further.