Rats Flashcards
Neophobia
The fear of strange new objects is called neophobia.
when you put a new object in a cage the rat will “freeze” and then groom itself avoiding
exploration for some time. This neophobic behaviour is normal and will always occur to come
extent when you add something new to their otherwise familiar environment. They will
overcome this response very quickly.
Territoriality
In the wild the female will stay close to the nest while the male
will move around 20 to 30 metres from the nest. domestication has softened this aspect of behaviour so important to survival in the
wild. It is possible, for example, to move laboratory adult female rats from one group to another
without inducing seriously aggressive behaviour. Females in groups with a male can be removed
when pregnant to litter down and wean their pups, subsequently, returning to the group again
later for mating.
Exploratory Behaviour
Wild brown rats use extensive exploratory behaviour to develop a detailed knowledge of their
territory and home range. They know the location of food and water, finding new alternative
sources and tunnels and escape routes from predators. Laboratory rats given the opportunity will
demonstrate similar investigatory and exploratory behaviour and it is this important part of their
capabilities that has been addressed in attempts to introduce environmental enrichment for
laboratory rats.
Holding or Handling
Observe the rats in your care and see the skill with which they use their fore feet to
manipulate and hold food as they eat it.
Huddling
Huddling starts at birth and persists for the first 18 days of life. During that period the pups
are unable to maintain their own body temperature. This is accomplished by huddling, which
becomes a positive, pleasurable, comfortable (comforting) behaviour throughout life.
Hoarding
Rats will collect food in their mouths in substantial amounts (mouthfuls) and return them to
the “safety” of the nest for consumption
Tail Hoarding
It has been noted that a female domesticated rat housed on her own may carry her tail in her
mouth across the cage. This behaviour is regarded as abnormal and indicative of social
deprivation and boredom. The presence of another rat and environmental enrichment is
required to correct this.
Scratching
This is another abnormal behaviour reported in environmentally deprived females, which
involves scratching the neck until it becomes abraded and scabs over.
Dominance and Submission
Dominance and submission is
demonstrated clearly when two rats confront one another resulting in one pushing under the
flank of the other, a behaviour called “crawling under”. The rat crawling under is demonstrating
submissiveness to the other rat which is dominant. In this manner a friendly interaction is
established.
Dominance may be demonstrated by one rat literally “walking over” another rat. In crawling
under the submissive rat grovels. In this case, the dominant animal is actively establishing the
hierarchy. In certain situations, dominance is further established by urinating on the submissive
rat.
“threat posture”
The back is arched and the legs are extended. The
flank is presented to the potential opponent and the movement is one of prancing. Often these
types of behaviour make the potential aggressor look bigger to the observer. This is an important
indicator of physical superiority in animals. Occasionally active aggression will follow. Factors that
might influence the outcome are the presence of females, strange urine odour and pheromones.
Nosing
This involves one rat gently pushing at the flank of the other rat towards the head end with
its nose. It seems to be a friendly gesture, perhaps attempting to elicit a favourable response. It
is also used by females in estrus on the males.
Smell
The rat has a highly developed sense of smell, using it as an important vehicle for
communicating via pheromones (secreted chemical messengers sensed by smell or olfaction) for
sexual signals, social dominance and stress. Odour assists the male in mating. Maternal
pheromones assist the pups in suckling.
The wild rat marks its trails (tunnels, etc.) with sebaceous material. This is recognized by the
rat in dark conditions and is believed important in its orientation.
Sound
Rats are able to hear sounds as high as 60 to 80 kHz (60 to 80,000 cycles per second) which
is very high and way beyond our upper level at 16 kHz (16,000 cycles per second). They are most
sensitive to sounds around 40 kHz
Touch
In the rat, certain hairs or bristles have developed a specialized tactile function. These are
CALAS/ACSAL Training Manual (Rev. 2005) FASCICLE 1 CHAPTER
Some Facts About The Origin, Domestication and Behaviour of Common Laboratory Animal Species 10
1-10-9
called vibrissae (whiskers). They are arranged around the head so that this part of the body is
highly sensory. The feet and the tail are also similarly tactile sensitive.
This tactile sense is highly developed and of great importance to a burrowing and nocturnal
animal with tactile orientation.
thigmotaxis
move in contact with vertical surfaces.
