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NFC: Zoology paper

A few people mentioned tht they wanted to see my research paper done in
zoology sometime...so here ya go.  I might add, I did recieve an 'A' on
it.  Please excuse the typos, my carpal tunnel syndrome makes it extremely
painful to type such a long document.




			Luke McClurg


 Fishes, unlike mammals, are an ectothermic species.  They are unable to
regulate their body temperatures and are thus subject to the temperatures
in their surrounding environments.  The temperature variations in their
environment will thus regulate their metabolism and both their need  to
take in nutrients and excrete wastes.  Scientific study has clearly proven
that these wastes are excreted in the form of ammonia and urea.  In most
instances of neutral pH (pH 6-8) approximately 90% of the total
nitrogenous waste is excreted acrss the gills, with ammonia accounting for
approximately 85% of this total.  Excretion of urea usually making up the
remaining 10-20%.(Wilkie, 1996)

 In one test involving the growth and metabolism of jouvenile turbot,
various experiments involving the effects of temperature were conducted.
The results were conclusive: the temperature of the fish's environment was
a major and even the deciding environmental factor in determining growth
rate, metabolism and nutitional efficiency.  This experiment proved that
temperature was positively related to ammonia excretion per fish
biomass.(Burel, 1996)

 Numerous studies have been performed ove the past decades on the subject
of ammonia excretion in fishes.  Many of these studies have been focused
on the sport fisheries industry. Hatchery raised fish pose a problem as
the most amount of fishes mut be reared in the least amount of space.  In
one experiment, trout reared in a hatchery were used to measure ammonia
excretion based upon normal versus abnormal feeding cycles.  One group of
trout were fed at midnight and another were fed at dawn.  It was
discovered that the fish fed at dawn, which were feeding on their natural
feeding phase, produced less ammonia than those fed at
midnight.(Gelineau, 1998)


 My own research has posed the following question:  "what role, if any,
does the water temperature play in the metabolism and excretion of ammonia
in fishes?".  I chose to use the common "comet" goldfish generally sold in
most pet stores as a 'feeder' fish for other species.  This species is
reasonably durable and adaptable to mild temperature and water changes.
Goldfish are also known for the large amounts of ammonia they excrete and
this is another reason for using this species.

 I place six small, 1-1 1/2 inches, goldfish in a standard 2 1/2 gallon
fish bowl and labeled it as "A".  I then put the sme number and
approximate size of goldfish in a second duplicate bowl and labeled it as
"B".  Bowl "A" was to be kept at the room temperature of 16 degrees
celcius.  Bowl "B" would be maintained, with the use of a 150 watt
submersible heater, at a temperatur approximately 6 degrees above this at
22 degrees celcius.  Temperature was to be monitored by identical floating
type thermometers checked for accuracy by myself before the experiment
began.  Tap water was used to fill the bowls to the same approxiamte leve
and heavy metals and toxic chemicals were removed with the use of two
products producd by Kordon:  Amquel and Novaqua.  Manufcturers suggestions
were used in dosing each bowl.  Ammonia contents would be monitored by
using a standard ammonia test kit manufactured by Aquarium
Pharmaceuticals, Inc.  The active ingredients in this kit are sodium
hydroxide and mercuric iodide.  The subjects were placed in their
respective bowls on a Tuesday evening at 21:00 and the first reading was
taken approximately 24 hours later and for the next progressive seven
night.  On day six the subjects in bowl "B" appeared to be under mild
respiratory distress.  On day seven the subjects in bowl "B" appeared to
be in greater respriatory distress than the previous day and two specimens
were dead.  The experiment was thus terminated.



 This test did yield some data.  We see in the following Table 1 that
starting on day 4, the ammonia level in "B" began to rise to measureable
levels.  It was this bowl that was kept at the warmer temperature.  Bowl
"A" does not gegin to show measureable amounts of ammonia unitl day 6, by
which time bowl "B" is now entering a zone that will be lethal to the test
subjects after long term exsposure.  At no time did the ammonia level in
bowl "A" reach dangerous levels during this test.

Table 1.

Test Day          "A" Ammonia level         "B" Ammonia level
--------          -----------------         -----------------

Day 1               0 ppm*                    0 ppm

Day 2               0 ppm                     0 ppm

Day 3               0 ppm                     0 ppm

Day 4               0 ppm                    0.5 ppm

Day 5               0 ppm                    0.5 ppm

Day 6              0.5 ppm                   3.0 ppm

Day 7              0.5 ppm                   3.o ppm

* - all measurements are in "parts per million"


 The conclusion of this test and resulting data seems to be this.  Water
temperatures do affect the amount of ammonia excreted by a fish in it's
environment.  The lower the water temperature, the slower the metabolic
rate of the fish and thus the lower amounts of ammonia excreted by the

 This experiment contained several errors.  Only two subject bowls were
used.  More accurate data could be obtained with the use of a wider range
of temperature levels both with the addition of more test subjects and by
varying temperatures on the existing subjects.  Far more intensive study
and experimentation would have to be done in order to draw any definitive
conclusions.  More accurate data might also have been received with the
use of purified water instead of tap water, which could release unknown
factors into the test.  Other controls in future experiments might include
exact measurements of all water, food and other additives place inot the
test bowls as well as a more accurate and equal distribution of overall
body mass of the test subjects between the bowls.  A lenghtier test over
several weeks or months would also be better suited for this type of
experiment.  These are only a few of the possible controls that would make
this experiment more accurate.


Burel, C. & Person-Le Ruyet, J. & Gaumet, F. & Le roux, A. & Severe, A.
1196: "Effects of Temperature on Growth and Metabolism in Jouvenile
Turbot", Journal of Fish Biology, Vol. 49

Gelineau, A. & Medale, F. & Boujard, T. 1998: "Effect of Feeding Time on
Postprandial Nitrogen Excretion and Energy Expenditure in Rainbow Trout",
Journal of Fish Biology, Vol. 52

Wilkie, M. P. & Wood, C. M. 1996: "The Adaptations of Fish to Extremely
Alkaline Environments", Comparative Biochemisty and Physiology, Vol. 113B


 A special thank you to Jan Hoover in his help with finding appropriate
research material to be used in this experiment.