Rats Flashcards
What is a rats lifespan?
2.5-3.5 years
Females live longer on average
What is an adult rats bodyweight?
400-800g
What is a rats body temp?
38*C
What is a rats respiratory rate?
70-150 b/min
What is a rats pulse rate?
260-450 b/min
What age is a rat sexually mature?
8-10 weeks
What is a rats Gestation period?
20-22 days
What type of young do rats produce?
Altricial young
Do rats perform coprophagia?
Yes but less active as they are omnivores
How do rats thermoregulate?
Increased salivation and find shade to cool down.
Tails and ears are important for heat dispersion as the blood vessels vasoconstrict and dilate according to temperatures.
They have a poor heat tolerance as they have few sweat glands and are unable to pant.
What are a rats incisors used for?
Fighting, Holding food, Excavating burrows, Gnawing
What colour are rats teeth and what gives them this colour?
Yellow/orange due to iron pigments
How do rats eyes appear?
Black, spherical, bulging appearance due to poorly formed 3rd eyelid.
Frequently blink.
How does a rats tail appear and what are its attributes?
Long tail, sensitive to pain.
Important for thermoregulation and balance.
Has 210 overlapping scales which are heavily keratinised on upper dermis.
Covered in yellow/orange sebum.
Explain the male rats external genitalia
Has testicles from 3-4 weeks of age.
Large oblong scrotum.
Anogenital distance twice as long in males than females.
No nipples.
Explain the female rats external genitalia
Anogenital distance shorter than in males.
Urethra opens at the base of the clitoris which is enclosed in a little prepuce.
6 mammary glands.
Vertebral column of the rat?
7 Cervical
13 Thoracic
6 Lumbar
4 Sacral
27-31 Coccygeal
Explain some skeletal attributes of the rat
The 6th cervical vertebrae has a modified rib fused to its transverse processes.
Ribs 1-7 articulate with the sternum and the last 3 are floating ribs.
Fore feet are well developed to allow grasping of food.
Tibia and Fibula are fused distally.
What are a rats venipuncture sites?
Lateral tail vein.
Lateral Saphenous Vein.
Ventral Tail Artery - warm tail to cause vasodilation before blood sample.
Rat Respiratory System
What is the nasal cavity involved with?
Respiration.
Humidifying and filtering incoming air.
Olfaction (smell) - 50% of the nasal cavity is lined with olfactory epithelium which gives acute sense of smell.
Rat Respiratory System
Explain the attributes of the lungs.
The right lung is divided into 4 lobes: cranial, middle, caudal, accessory lobe.
The left lung is smaller and not divided into lobes.
Rats Cardiac
Where is the heart positioned?
On the left side of the body.
Can be palpated between ribs 3 and 5.
Rats Digestive System
What diet do rats have?
Omnivores - feed frequently.
Rats Digestive System
What is the GI transit time?
12-24 hours
Rats Digestive System
What is the Dental Formula?
I1/1, C0/0, PM0/0, M3/3 x2 = 16 teeth
Rats Digestive System
What does the Diastema do?
Helps close off the back of the mouth to allow gnawing hard substances.
Rats Digestive System
What type of stomach and digestion does the rat have?
Simple stomach.
Monogastric digestion.
Rats Digestive System
What does the large intestine do?
Allows digestion of plant material
Rats Digestive System
Do rats have a gall bladder and why?
No gall bladder because the intestine are efficient at absorbing nutrients and rats have a high level of lipase in their blood which aids the breakdown of fats.
Rats Digestive System
How does dentition aid in digestion of food?
Food is grasped with fore paws.
Food is chipped by incisors and ground by molars.
Rats Dentition
At what age do molars stop growing?
4 months
Dentition
What happens in the diastema when gnawing?
Cheek folds form in the diastema when gnawing enabling the animal to gnaw at hard objects without swallowing sharp materials.
