Bachelor Veterinary science is a mother of all health.

veterinary science

1. Department of veterinary science
Veterinary parasitology laboratory
practical class for BVSc students

By;
Mekonnen Tona

2. INTRODUCTION
•Laboratory procedures are an essential diagnostic
component in field of veterinary science.

•The role of the veterinary technician is to collect store,
transport and process samples and then analyze and report
the findings.

•The following topics incorporate discussions on the use of
common laboratory equipment, proper quality control
methods, parasitology and in animals and their laboratory
diagnosis.

3. Laboratory Safety and Rules
Clinical laboratories can be hazardous if the rules are not
followed.
During a laboratory course a student may handle materials
which are carcinogenic, poisonous, flammable, and
explosive.
Mostly accidents occur in the laboratory are a result of
carelessness, impatience, improper or unauthorized
experimentation, and disregard for safety rules or proper
operating procedures.

4. Laboratory Safety and Rules cont…
In order to minimize the chances of an accident in the
laboratory certain rules and regulations must be obeyed at
all times when one is working or observing in a clinical
laboratory.
Therefore, it is not advisable for anyone to work in a
laboratory without proper knowledge of the dangers
involved.
The essential requirements for any work with infectious
agents and biohazardous chemicals are as follows:

5. Laboratory Safety and Rules cont…
1.The laboratory should be easy to clean, with surfaces that
are impervious to water and resistant to chemicals.
2.Personnel access to the work area should be restricted.
3.PPE, shall be worn in the laboratory and removed when
leaving the laboratory.
4.The laboratory door should be closed when work is in
progress and ventilation should be provided by extracting
air from the room.
5.Food or drink shall not be stored or consumed in
laboratories.
6.Smoking and/or application of cosmetics shall not take
place in the laboratory

6. Laboratory Safety and Rules cont…
7.Pipetting shall not be done by mouth. Always use pipetting
devices
8.Care shall be taken to minimize the production of aerosols. Be
careful around Bunsen burners.
9.Emergency response plans should be developed to deal with the
biohazard of spills.
10.Used laboratory glassware and other contaminated material shall
be stored safely. Long hair should be secured behind your head.
11.No infectious materials and biohazardous fluids shall be
discarded down laboratory sinks or any other drain.
12.Label all materials with your name, date, and any other
applicable information (e.g., media, organism, etc.
13.Any accidents or incidents shall be recorded and reported to the
Safety Officer.

7. Laboratory Safety and Rules cont…
Personal protective equipment (PPE)

8. Laboratory Safety and Rules cont…
Do’s Do Not’s
Always wash your hand Mouth pipetting is prohibited
Wear a laboratory Coat Eating and drinking inside Lab
Maintain gloves Using cell phone
Disinfect your work place Wearing jewelries at the Lab
Always ask for instructions Working alone

9. Major laboratory equipment’s and reagents
Microscopes

10. Major laboratory equipment’s and reagents
cont…
Equipment Functions
Microscopes To examine microorganisms which can’t be seen by naked eyes
Bunsen Burner To heat or boil solution in laboratory
Autoclave To sterilize the equipment medias and other solutions
Hot air Oven To sterilize metallic equipment and non-volatile solution
Refrigerator To preserve the samples, media, reagents and other specimen
Incubator Used for bacterial or fungal cultures
Safety Cabinet To rescue the exposure of the operator and the lab contamination
Inoculation loop Used to inoculate test samples into culture media for bacterial or
fungal cultures, antibiograms, etc.

11. Major laboratory equipment’s and
reagents cont…
Petri dish To act as a supporting container to hold the culture medium
Flask To measure and prepare media
Beaker To measure and transfer the solution
Cylinders To supply adjusted amount of C
2O
Staining racks To place slides to be stained
Coverslip To cover the specimen under the microscope
Balance To measure the weight of an specimen
Pipette To transfer quantified volume of specimen or solution
Microtitre plates For ELISA
Wire mesh To place the beaker or flask on top of the Bunsen rack
Filter paper To filter the solutions

12. Major laboratory equipment’s and reagents
cont…
Tissue culture bottles To grow or keep alive cells or tissue from a living organism, e.g. stem cells
Candle jar used for anaerobiosis
Anaerobic Jar Production of anaerobic conditions for organisms that die in the presence of even
little oxygen (anaerobiosis), e.g. tetanus bacteria
Gas-pack Releases gases to remove oxygen from a closed container, usually for
anaerobiosis
Gas cylinder To carry gas used for supply to Bunsen burner
Swab cotton To prepare swab
Water Bath Used to heat medium gently (to around 45-55 degrees Celsius) during media
preparation
Thermal cycler Used to amplify segments of DNA via the polymerase chain reaction (PCR)
process
Vacuum pump To draw out the air from any closed chamber before pumping back CO2, O2 or
N2, usually for anaerobiosis
Bijou bottle A cylindrical small glass bottle with a screw cap used as a culture medium holder

13. Major laboratory equipment’s and reagents
cont…
Durham's tube Used to detect gas production in sugar fermentation media; the
tube is placed in an inverted fashion so that gases produced get
trapped in it and do not float away to the surface
Blood sample
bottle
To collect blood by venipuncture
McCartney's bottle For simultaneous solid and liquid cultures
Pre-sterilized
disposable
container
Sample collection
Pre-sterilized
disposable syringe
/ autodestruct
syringes
Sample collection
Pre-sterilized
disposable swabs
Sample collection

14. Reagents and media used in Laboratory and
their functions
Reagents Functions
Carbolfuchsine To stain bacteria Crystalline violet To stain bacteria
Crystalline violet To stain bacteria Crystalline violet To stain bacteria
Ethyl alcohol Decolorize the stain
Gram’s Iodine Act as mordant
Methyline blue Used in simple stain and counter stain in Acid Fast Stain
Safranine Used in gram stain
Sulpheric acid Used in spore stain
Emulsion oil Used to see specimen under high magnification
Hydrogen peroxide Used in Catalase test
Potassium hydroxide Used in KOH test
Covacks reagent Used in Indol test
Indian Inc Used to stain fungus
Geimsa Used in simple stain
Media Functions
Sabourad dextrose agar To culture fungus
Muller hinten agar For antibiotic sensitivity test

15. Reagents and media used in Laboratory and their
functions
Brelliant green agar Used in identification of Enterobacteriacae family
Modified Edward
media
Selective media for Streptococcus
Mc-Conkey agar Selective and differential media for isolation of gram negative bacteria
Mannitol salt agar Selective media for Staphylococcus
Nutrient agar General and commonly used solid media for primary culture
Nutrient broth General and commonly used liquid media for primary culture
Blood agar Enriched media for culturing of many organisms
Choccolate agar For culturing of family Pasteurellacae particularly Haemophilus
SIM media To identify Citrate utilizers
Urease agar To identify urease utilizers
CAMP media Used for identification of Staphylococcus and Listeria species
TSI agar Used in identification of Enterobacteriacae family
MRS agar Used in identification of Lactic Acid Bacteria

16. SAMPLE COLLECTION, SUBMISSION
AND DIAGNOSIS
The collection of infectious agent from the host or from
other origin should be under the safety guidelines.
The protective measures are quite important.
The principles of laboratory safety are needed to be
considered at field during collection and submission of
laboratory specimen.

17. Sample collection (spacemen)
Many people fail to appreciate the necessity of collecting a
good quality sample.
It is not enough simply to succeed a transferring a small
quantity a fluid to the sample bottle, most of the problems
caused by poor sample quality are only evident in the
laboratory.
There are different types of samples (specimen) and each of
these has special procedure of collection.

18. Sample collection tools

19. Types of samples
Blood sample
Fecal sample
Urine sample
Skin scraping sample
Swab sample
And sputum sample

20. Common procedure of sample taking
1.Restrain the animal
2.Take the sample
3.Label the sample
4.Storage
5.Transport to the laboratory room
6.Laboratory record registering
7.Make a copy the sample
8.Analyze the result
9.Interpret the analysis

21. Fecal sample
Sample collection in parasitology is important in achieving
accurate results.
In animal medicine, fecal samples are collected directly
from an animal’s rectum.
If samples cannot be examined within 2 hours, they should
be refrigerated.
The volume of sample should be adequate. A minimum of
10g of fresh feces should be collected.

22. Pooled samples
Samples obtained from a group of animals that are housed
together.
The sample represents the group.
When collecting the samples, the label should clearly state:
Owner
Date/time of collection
Pen number
Number of animals contained within this pen

23. Gross examination
To examine the physical characteristics
1.Consistency:
Is it soft, watery, or hard
2. Color:
gray stool can indicate pancreatic insufficiency
3. Blood, Mucous, Gross parasites etc..

24. Microscopic examination
1. Direct fecal smear
One advantage to the direct smear method is that is
requires very little feces.
Material
1.Microscope slides
2.Coverslip
3.Saline
4.Wooden applicator stick

25. Microscopic examination cont..
Procedure
1.Use wooden applicator stick, mix a small amount of
sample into a few drops of saline in the center of a slide.
2. Blend gently until the mixture is homogenous.
3.Spread out the mixture to a thin layer.
4.Remove any large fecal pieces.
5.Place a coverslip over the sample.
Examine: microscopically

26. Simple fecal flotation
Several types of fecal flotation solutions that are used as a
semi-quantitative method of evaluating a fecal sample.
In these methods, an estimate is made of the number of
parasite ova per gram of feces.
The principle of this method is to use the differences in
specific gravity of parasite eggs and cysts from that of
fecal debris and the solution.

27. Simple fecal flotation cont…
A fecal sample is mixed with a flotation solution
consisting of various salts or sugars added to water to
increase its specific gravity.
Parasite eggs and cysts float to the surface, while most
fecal matter sinks to the bottom.
A common flotation medium is sodium nitrate solution.

28. Simple fecal flotation cont…
Materials
Two specimen containers (or wax paper cups)
Tongue depressor
Flotation solution
Fecal shell vial (or test tube)
Metal tea strainer
Coverslip
Microscope slide.

29. Simple fecal flotation cont…
Procedure
1.Add 2g of fresh feces to a container, such as a specimen
container or a wax paper cup.
2. Add flotation solution to the feces and mix well using a
tongue depressor.
3.Strain this mixture through a metal tea strainer into the
second specimen container.
4. This strained mixture is then added to the fecal shell vial
(or test tube).

30. Simple fecal flotation procedure cont…
5. Add more flotation solution to the shell vial until a
meniscus is formed.
6. Place a coverslip over the meniscus and let it sit for 10–15
minutes.
7. After the allotted time, remove the coverslip by lifting it
directly upwards.
8. Place the coverslip onto a microscope slide. the coverslip.
9. Examine microscopically

31. Centrifugation technique
The centrifugation technique is more efficient at recovering
parasite ova from a sample than simple flotation method.
Materials
Two specimen containers (or wax paper cups)
Metal tea strainer
Tongue depressor
Test tubes
Flotation solution
 Coverslip
Microscope slide

32. Centrifugation technique cont….
Procedure
1.Mix 1g of feces in 10mL of flotation solution in a
specimen container or wax paper cup until a suspension is
formed.

2. Pour the mixture through the metal tea strainer. Using
the tongue depressor, press the material into the strainer to
extract as much liquid as possible.


3. Pour the liquid into a centrifuge tube and centrifuge
the sample at 1500rpm for 3 minutes (remember to always
counter balance).

33. Centrifugation technique cont….
Procedure
4. Decant the supernatant, and add flotation solution. Mix well
into the sediment. Add more flotation solution until a meniscus is
formed.

5. Place a coverslip over the meniscus.

6. Return the tube to the centrifuge and centrifuge the sample
at 1500rpm for 5 minutes. (Remember to counter balance)

7. After centrifugation, remove the coverslip by lifting straight
upwards. Place the coverslip onto the slide and examine
microscopically.

34. Baermann technique
The Baermann Technique is used to recover parasite larvae, not
ova.
Materials
Baermann apparatus: Consisting of a funnel, support
structure, short length of tubing at the end of the funnel, and a
clamp at the end of the tubing.
Gauze or cheesecloth
Warm water
Microscope slide
Coverslip

35. Baermann technique cont..
Procedure
1.Wrap 5g of feces in gauze and lay on the support screen
inside the funnel of the Baermann apparatus.

2.After ensuring the clamp at the end of the tubing is closed,
add warm water until the sample is covered.

3. Allow the sample to sit for at least 8 hours (or overnight).

4. After the appropriate time has lapsed, loosen the tubing
clamp slightly to withdraw a large drop of liquid onto a slide.

5. Add a coverslip to the sample and examine
microscopically

36. Ancylostoma/hook worms

37. Trichuris/whipworms

38. Toxocara

39. Taenia/ Tape worm

40. Aug, 2024
Thank you