3. 3
A zoological specimen is
an animal or part of an
animal preserved for
scientific use
Examples include
◦ Bird and mammal skins
◦ Mounted specimens
◦ Eggs and nests
◦ Skeletal material
◦ Casts
◦ Foot prints and burrows
◦ Pinned insects
◦ microscope slides
Introduction and objectives
4. 4
Specimen preservation
means long term
preservation of organisms
in suitable medium like
formalin, alcohol, etc. in
the best possible natural
condition.
It is a fundamental
requirement in
biological/medical science,
agriculture, and
biotechnology
Introduction and objectives
5. 5
The scientific description of
an animal species requires
◦ Detailed examination
◦ Description of a
representative type
specimen
◦ Series of specimens which
are deposited, catalogued
and maintained in a
museum
Reference for other workers
in the future
Introduction and objectives
6. 6
Natural history museums are
repositories of zoological
specimens:
◦ To verify the identity of a
species
◦ Study and research
◦ To study relationship of
animals with each other
◦ To increase knowledge
of zoology
◦ To increase public
awareness and interest
Introduction and objectives
7. Types of preservation techniques
Animal Preservation
Techniques- Types
of preservation
techniques
8. Types of preservation techniques
This process of preparing,
stuffing, and mounting the
skins of animals so that they
look like living
Skull and other bones are
retained to create a dummy
or mannequin
This involves removal of skin
of animals
Preservation and tanning of
the skin
Mounting on a mannequin
made from wood, wool, etc.
9. 9
Specimen preservation
involves immersing the
whole animal in a fluid
preservative
Fluid preservation may
change the fur colour, skin
coat or integument
properties
Purpose:
◦ For studying anatomy and
histology
Types of preservation techniques
10. 10
It involves preserving the
specimens by applying
some chemicals in dry
conditions
Study skins with skulls /
partial skeletons (some
bones in skin)
Purpose:
◦ For studying colour, hair
quality and moulting
patterns
Types of preservation techniques
11. 11
A special form of drying that
removes all moisture,
specimen is freeing and then
placing in a strong vacuum
The water then sublimates ,
that is, it directly changes to
vapors
Purpose:
◦ To study mounted skins with
partial or entire skeleton
(some bones may remain in
the skin)
Types of preservation techniques
13. 13
Killing and relaxing of
animals
Fixation
◦ Stops cellular respiration
◦ Kills decomposers like
bacteria and fungi in the
organisms
◦ Good penetrating ability
Storage in bottles, jars
vials, trays.
Methods of preservation
14. 14
Formalin (most commonly used
fixative)
Usage
◦ It is used for vertebrates only
◦ It is avoided for long-term
storage since it is acidic and
difficult to handle.
◦ Mostly it is used where
colour is important since
alcohol dissolves most
colours almost immediately.
◦ It penetrates more rapidly
and internal organs remain in
better condition
Methods of preservation
15. 15
Industrial Alcohol (for both
fixing and storage)
Usage
◦ Alcohol is usually not used
for vertebrates
◦ Used for long-term storage
of the animals
◦ Colours of specimen is lost
immediately
◦ Glycerine in alcohol is used to
presreve colours and
flexibility
◦ For long-term preservation,
70-75% alcohol is used
Methods of preservation
16. 16
Isopropyl alcohol
Usage
◦ It is cheap and easy to obtain.
There are different strengths
available (70% and 90%)
◦ 40% alcohol is preferred
solution
◦ it can be hard on the
specimens and tends to make
them brittle with time
Buffering: It can be buffered
with a few drops of glycerin
and a pinch of calcium
carbonate
Methods of preservation
19. A single specimen may be a
composite of preparations
sharing a unique number.
An example may be a
vertebrate with an alcohol-
preserved skin and viscera, a
cleared and stained head, the
post-cranial dried
skeleton, slides of various
organs, and frozen tissue
samples.
This specimen could also be a
voucher for a publication, or
photographs and audiotape.
Applications of animal preservation
20. A voucher is a representative
specimen of the animal used in
a study, such as collected in
an ecological survey or a
specimen which was the source
of DNA for a molecular study.
Voucher specimens confirm the
identity as they are a backup
against misidentification,
changing species concept
which may mislead the results.
Type specimens are a special
type of voucher specimen used
in taxonomy
Applications of animal preservation
21. These specimen may
have historic
significance for instance the
specimens collected
by Johann Baptist von Spix
He collected specimens of
plants, insects, mammals,
birds, amphibians and fish
during his expedition to
Brazil
These constitute an
important basis in National
Zoological Collection in
Munich
Applications of animal preservation
23. High acidity is likely to render
the specimens brittle and
transparent
Temperature, humidity, etc.
Crabs and prawns may also be
killed in formalin, but this
renders their joints hard and
brittle, and their limbs cannot be
easily manipulated
The larger arthropods
(especially those with hard
exoskeletons) sometimes need
to be injected with 10% formalin
to prevent their innards from
rotting.
Factors affecting preservation
Editor's Notes
A teaspoonful of glycerine in a quart of alcohol helps to preserve natural colours and to keep integuments flexible.
when they are observed under a microscope they are opaque or nearly invisible to the naked eye.
Enables a proper study of their size, shape, arrangement and other structures.
Microorganisms must be fixed & stained to increase visibility, accentuate specific morphological features,
when they are observed under a microscope they are opaque or nearly invisible to the naked eye.
Enables a proper study of their size, shape, arrangement and other structures.
Microorganisms must be fixed & stained to increase visibility, accentuate specific morphological features,
when they are observed under a microscope they are opaque or nearly invisible to the naked eye.
Enables a proper study of their size, shape, arrangement and other structures.
Microorganisms must be fixed & stained to increase visibility, accentuate specific morphological features,
when they are observed under a microscope they are opaque or nearly invisible to the naked eye.
Enables a proper study of their size, shape, arrangement and other structures.
Microorganisms must be fixed & stained to increase visibility, accentuate specific morphological features,