Lab -3Preservation of Specimens
A- Refrigeration for keeping ( Media , solution culture )
B- Freezing (All the organs , Lymph glands, milk put in suitable
container and surround it extremely with piece of dry ice and send
with clinical pathology chart . This suitable for long distance to
keep the coldness for long time (12-16) hours ( size of organ 3
inch³ )
Preservative Chemicals :
1- Feces :
- 3-5% formaline for parasite ,
- Freeze for virology and toxicology (put in aluminum fouls and
freeze).
2- Organs :
- Freeze for bacteriology and virology test .
- Organ and tissue put in 50% glycerin for virology.
- 10% formaline for histopathology study.
3- Fluids (serum , plasma ,cerebrospinal, synovil) (for isolated
pox)(saline + 1% agar )
(100 cc saline + 1gm agar) or 50%
glycerin and phosphate buffer (50%) .
4- Urine : 1-2 drop of formaline 40% for 30 ml of urine for
cytological examination .
- General preservative Thymol (500 mg tablet)
take 30 ml
of urine for general examination .
- Chemical examination of urine :
1- Refrigeration (4ºC)after 1 hour from collection time .
2- 10 ml of urine in test tube and add 1ml of Tolune
5- Serum :
1- Freezing for six month to year avoid freezing and Thawing .
2- Phenol 0.5% (0.5gm/100ml) ,(15 ml
(3ml
50 mg
10mg )
3- Merthiolate : 1/10.000 for serum.
Questions :
Q1- What are the types of method used to keep serum ?
Q2- Mention the methods for keeping urine sample ?
All 100ml)
Lab. -4-
Parasitology
There are three methods for diagnosis and it is essential to make a correct
diagnosis and to evaluate the parasitosis quantitively as well as
qualitatively :
1- The
physical
examination
include
appearance
of
feces
(consistency, colour , odour, abnormal constitute ).
2- Requirement : plastic gloves ,Rubber gloves , beaker, wooden
spatulas, containers the size determined by the amount of feces .
3- Examination must be done not longer than 24 hours and at least
( 5 – 10 gm ) .
The methods is :
A- Direct method : 1/2 gm fresh and concentration solution the
filtered by sieve the residue diluted for few minute unit the
bubble have all escaped then carefully float a cover – glass on
the top this method used in heavy infestation parasitosis.
B- Flotation : Take 1-2 gm of fresh feces mixed with concentrate
NaCl (30-50 ml) inside small beaker make mixing and sieving
and then put cover slide for 10-20 minutes, remove like covered
put on glass slide and examine under low power microscopic ;
suspended the eggs that have light specific gravity float up
specially nematode and cestoda the eggs stick on the cover
slide.
C- Sedimentation : Take 2-3 gm of fresh feces mixed with 60 ml
water the suspension is strained through fine sieve ,the filtrates
is stored for one hour and supernatant is decanted it is necessary
to repeat the sedimentation then stirred homogeneously with
glass bar a few drops are applied to microscope specially the
specific gravity eggs mostly trematoda and metastrogylus .
D- Sedimentation for lung (Baermann - apparatus)
It consist of glass funnel clamped to a standard to the bottom of
the funnel a rubber tubing is fitted (10 cm long) the funnel
cover with gauze meshes (double layers) and fill with water at
(30-40)ºC for (3-6) hours the nematode larvae will be
swimming in petridish for detected lung worms Dictycolous
viviparous .
- Mac Master method for counting eggs by using 60 ml saturated
NaCl + 2gm fresh feces in special slide full the two chamber
(2 x 0.15 ml) count the eggs in two chambers
N x 100 = e. p.g. (eggs per one gram feces)
There are three genus of
1- Nematode (Hemonchus , Ascaris, Ostertagia in sheep & goat
, Oxyuris equi in horse)
2- Trichostrogylus (Parascaris equirum in horse) , strongylus
spp.
3- Cestoda (Taenia spp., Moneizia, Diphlidum caninum)
Skin Parasite : The are many types of ectoparasites , ( Mite, Lies)
Psoroptes scabiei
Sarcoptes scabiei
It affected all area of the body that
affected all the area without wool
cover the wool.
at face, muzzle, ear.
Causing dry hairs
Causing dry hairs
The method for diagnosis the a gents by skin scraping by scalp from the
marginal lesion even oozing blood then put it in petridish boiling and
adding KOH 10% and heat gently until air bubble appear for dissolve the
keratin to see the mites.
Keeping time (preservative) of feces :
- Cooling at (4 ºC) for 3 days
- Formaline (5-10%)
- Potassium Dichromate (2.5%) for coccidia