Home-cage measurements    Hand-held Observations    Open Field Activity     Stimulus Response     Nervous and Muscle Measurements

Please click the appropriate link above to enter the NBRP Rat Database or check for detailed explanation on FOB below.

 

Functional Observational Battery (FOB) Observation Procedures

(1) Home-cage measurements
(Observe the animals from outside the cages, taking care not to agitate them. Do not touch the animals.)

1) Body position: Choose the word from the following list that best describes the animal's posture (classification).


S (sitting or standing): Sitting or normally standing
A (asleep): lying on side curled up or crouching
R (rearing): Standing on hindlimbs
H (hunchback): Back is rounded, even when walking, and animal appears to be holding stomach
L (lying): Lying on side, limbs in air
F (flattened): Animal is spread out with abdomen pressed to floor
C (catalepsy): Animal is in a cataleptic-like state; may be 1 of a variety of postures, but animal must maintain an unnatural posture
Note: Only an assessment of S, A or, if of a mild degree, R is considered normal.


2) Respiration: Choose the item from the following list that best describes the rate and extent of breathing (score).


1: Normal
2: Slightly incomplete/fast and shallow, bradypnea (breathing either fast and shallow or slow)
3: Moderately incomplete/rapid breathing, difficulty breathing (breathing very fast and shallow or very shallow and labored in appearance)
4: Severely incomplete/wheezing, breathing with mouth open (wheezing or breathing with mouth open)
5: Weak breathing (breathing very little)
3) Clonic involuntary movement: Choose the applicable item from the following list (score).
1: None/normal
2: Repetitive mouth/jaw motion
3: Twitching of limb, auricles or head
4: Generalized tremors
5: Clonic seizure
6: Trembling


4) Tonic involuntary movement: Choose the applicable item from the following list (scored).


1: None/normal
2: Extending contraction (limb or limbs extends and becomes rigid)
3: Sudden jumping (all limbs come off floor)
4: Tonic extending convulsion
5: Tonic convulsions seen with respiratory distress, seizure or death


5) Vocalization: Check for spontaneous vocalization. Choose the applicable item from the following list (scored).


1: No vocalization/normal
2: Vocalization noted


6) Palpebral closure: Choose the item from the following list that best describes the closure of the animal's eyes within the cage (scored).


1: Open
2: Slightly sagging/half shut (eyelids slightly lowered)
3: Shut (eyelids are closed)

(2) Hand-held observations
(Observe animals' reactions when they are removed from their cage and held.)

1) Reactivity: Choose the item from the following list that best describes the ease with which the animal can be removed from its cage (scored).


1: Very easy (animal sits and allows itself to be picked up)
2: Easy/normal (animal does not resist)
3: Somewhat difficult (rat stands)
4: Difficult (animal cringes and becomes rigid or runs around and is difficult to grab)
5: Very difficult (animal attacks)


2) Handling: Choose the item from the following list that best describes the ease with which the animal can be handled after having been removed from cage (scored).


1: Does not resist/ very easy to handle
2: Squeaks or does not squeak but exhibits mild resistance; easy to handle/normal
3: Animal freezes and does not move; becomes rigid in hand
4: Very difficult (animal struggles, squirms, appears distressed, attempts to bite)


3) Palpebral closure: Choose the item from the following list that best describes the closure of the animal's eyes when held in the hand (scored).


1: None/normal/ (eyes are open)
2: Slightly sagging/half shut (eyelids slightly lowered)
3: Shut (eyelids are closed)


4) Lacrimation: Holding the rat, observe areas around eyes and choose the item from the following list that best describes the animal's condition (scored).


1: No lacrimation/normal
2: Moisture only around eyes
3: Moisture flows from eyes


5) Salivation: Holding the rat, observe areas around mouth and choose the item from the following list that best describes the animal's condition (scored).


1: No salivation/normal
2: Moisture only around mouth
3: Moisture flows from mouth


6) Piloerection: Holding the rat, observe coat (for degree of piloerection) and choose the item from the following list that best describes the animal's condition (scored).


1: None/normal
2: Around head and back (mild piloerection only around head and back)
3: Generalized (piloerection all over body)


7) Others (to be recorded as description): Note in detail any findings related to dirtiness of hair cast, bite marks, missing nails, gauntness (stomach can be touched, median vertebrae protrude) or death (findings).
Enter a minus sign (-) in the findings column if no such behavior is observed.

(3) Body temperature
Measure rectal temperature using a thermister thermometer(Measurement data). 

(4) Open field activity
 (Gently place each animal in the center of a field and make the following 10 observations for 3 minutes. If an animal fails to move during the 3-minute observation period, lightly prod it in the open field after observations are complete to check for loss of movement, recording observations.)

1) Number of rearings: Count with a counter the number of times the animal completely removes its forelimbs from the floor and the number of times it supports itself on a wall during the 3 minutes (counted).


2) Clonic involuntary movement: Choose the applicable item from the following list (scored).


1: None/normal
2: Repetitive mouth/jaw motion
3: Twitching of limbs, auricles, or head
4: Generalized tremors
5: Clonic seizure
6: Trembling


3) Tonic involuntary movement: Choose the applicable item from the following list (scored).


1: None/normal
2: Extending contraction (limb or limbs extends and becomes rigid)
3: Sudden jumping (all limbs come off floor)
4: Tonic extending convulsion
5: Tonic convulsions seen with respiratory distress, seizure, or death


4) Gait: Choose the item from the following list that best describes the animal's gait (classification).


N (normal): Head is horizontal, abdomen rises slightly above floor, and body moves up and down slightly during walking
D (drag): Animal drags body, abdomen touches floor, and body wobbles
H (hindlimbs exaggerated): Animal spreads or drags hindlimbs, unable to support weight of body
HU (hunched): Back is rounded or animal crouches
T (tiptoes): Animal walks on tiptoes
A (ataxia): Loss of motor coordination, excess swaying , animal lurches and sways when walking


5) Movements: Choose the item from the following list that best describes the animal's movement, disregarding gait. Also consider decreases in movement over time (scored).


1: Highly decreased
2: Slightly decreased
3: Normal
4: Slightly increased
5: Highly increased


6) Arousal: Choose the item from the following list that best describes the animal's activity. Also consider decrease in activity over time (scored).


1: Highly decreased (paralyzed; coma)
2: Moderately decreased (mildly numb; only moves head)
3: Slightly decreased (sometimes does not move but engages in exploratory activity)
4: Normal (keeps guard up and engages in exploratory activity)
5: Slightly increased (mildly excited or tense; sudden lurches forward and stillness)
6: Highly increased (highly alert; runs or moves body suddenly)


7) Occurrence of stereotype: Check for turning around, stereotypical preening, squeaking, shaking head, and other repetitive and stereotypical behavior (findings).
Enter a minus sign (-) in the findings column if no such behavior is observed.


8) Abnormal behavior: Check for abnormal behavior (e.g., squirming, running backwards, labored movement, squealing), disregarding stereotypical activity  (findings).
Enter a minus sign (-) in the findings column if no such behavior is observed.


9) Number of defecations: Count the number of feces defecated on the open field during the 3 minute observation period. Replace the paper liner after observations if it is dirty (counted).


10) Number of urinations: Count the number of urine stains on the open field left during the 3 minute observation period. A stain left by a rat moving while urinating shall be considered 1 stain. Replace the paper liner after observations if it is dirty (counted).

(5) Stimulus response

1) Approach response: Slowly move the tip of a dull object (e.g., tweezers) up to 2-3 cm in front of the animal and hold there for 4 seconds. Choose the item from the following list that best describes the animal's reaction to the dull object (scored).


1: No reaction
2: Slowly approaches, sniffs and pulls back/normal
3: Twitches (muscular tenseness)
4: Exhibits a violent overreaction such as jumping, biting, squeaking or attack


2) Touch response: Choose the item from the following list that best describes the animal's reaction to being gently touched on the abdomen with a dull object (e.g., tweezers) (scored).


1: No reaction
2: Slowly retreats/normal
3: Twitches (muscular tenseness)
4: Exhibits a violent overreaction such as jumping, biting, squeaking or attack


3) Eyelid reflex: Choose the item from the following list that best describes the animal's reflex upon being touched on the eyelid with a dull object (e.g., tweezers) (scored).


1: Does not blink
2: Blinks/normal


4) Pinna reflex: Choose the item from the following list that best describes the animal's twitch reflex upon being touched on the auricle with a dull object (e.g., tweezers) (scored).


1: Auricle does not twitch
2: Auricle twitches/normal


5) Sound response: Choose the item from the following list that best describes the twitch reflex of the animal's body upon having a clicker sounded approximately 5 cm from its back (scored).


1: No reaction
2: Mild reaction, hears sound/normal
3: Twitches (muscular tension)


6) Tail pinch response: Choose the item from the following list that best describes the animal's response to pain upon having the base of its tail squeezed with tweezers or a similar implement (scored).


1: No reaction
2: Looks back, moves forward and lightly squeaks/normal
3: Twitches (muscular tension)
4: Exhibits a violent overreaction such as jumping, biting, squeaking or attack


7) Pupillary reflex: Shine a penlight in the animal's eyes (scored).


1: Does not contract
2: Contracts


8) Righting reflex: Choose the item from the following list that best describes the animal's response to being dropped, belly up, from a height of 30 cm. Skip if animal is paralyzed or in an extremely poor state (scored).


1: Lands on four limbs/normal
2: All limbs do not touch at once
3: Lands on side
4: Lands on back

(6) Nervous and muscle measurements

1) Abdominal tone: Choose the appropriate item from the following list upon holding the animal in the hand and touching the abdominal muscles (scored).


1: No resistance (soft)
2: Normal (proper hardness)
3: High resistance (very hard)


2) Limb tone: Choose the appropriate item from the following list upon holding the animal in the hand and touching the muscles of the limbs (scored).


1: No resistance (soft)
2: Normal (proper hardness)
3: High resistance (very hard)


3) Grip strength: Use a small animal grip measurement device (for measuring forelimbs and hindlimbs). Take care that the strength of the measurer is not recorded by the device (measured).


(1) Engage animal's forelimbs on wire screen to which a strain gauge is horizontally attached.
(2) Gently pull backward along the wire screen until the forelimbs release.
(3) Record the peak value shown on the device.
(4) Engage the animal's hindlimbs on wire screen to which a strain gauge is attached at a 45 degree angle in a manner similar to that described above.
(5) Take 2 measurements for the forelimbs and 2 for the hindlimbs.
(6) Measure in kgf (kilograms force), record absolute values and determine the mean of the 2 measurements.


4) Landing foot splay (indiscrete data)


(1) Spread recording paper on testing platform.
(2) Cover the bottoms of the feet of the animal's hindlimbs with ink and pick up by the neck or back.
(3) Drop the animal when it is at rest, stomach down, onto the testing paper from a height of 30 cm.
(4) Perform the above actions twice.
(5) Take measurements in millimeters as the linear distance between the heels, recording absolute values and determining the mean of the 2 measurements.

 (7) Pupil size
Measure the pupil diameter using a mini master loupe (Measurement data).