Lecture 27-28: Rabbits vs. Rodents

what is important about the skin and hair of rabbits?

• very delicate

• easily tear or rip when clipping fur

• lack footpads

female rabbits possess a

dewlap

where are pododermatitis risks located on rabbits?

points of the hock and tips of third phalanges

what are the only glandrous areas of the rabbit?

nose tip, scrotal sacs, and inguinal folds

what is this pointing to?

dewlap

what is this picture showing?

pododermatitis lesion at hock

what is this picture?

rabbit scrotal skin

what are the rabbit scent glands?

• chin gland

• perineal glands

• inguinal glands

what is this rabbit doing?

scent marking with chin gland

what are these arrows pointing to?

inguinal scent glands

what is this picture showing?

perineal scent glands

cornea of rabbit eye =

30% of eyeglobe

rabbit eye position

• lateral position of eye globe in skull

• wide field of view by OU

OU =

ocular universal

OD =

ocular dexter

OS =

ocular sinister

what kind of vision do rabbits have?

binocular vision

what do rabbits have right behind their incisors?

peg teeth

what is this?

peg teeth

the rabbit GI tract is designed for

hindgut fermentation

what does hindgut fermentation mean for rabbits?

they rely specifically on their cecum to digest fibrous plant material

where is the cecum located in the rabbit?

superficially in the caudal peritoneal cavity

what is the arrow pointing to?

cecum

what are these GI structures?

A - stomach

B - small intestine (jejunum)

C - cecum

D - ileum

E - colon

what side of the body is the descending duodenum on?

the right

label these structures.

A - lymphoid appendix

B - sacculus rotundus

C - duodenum

D - ileocecal junction

A and B are both GALT

what is a cecotroph?

soft, nutrient-rich feces produced by rabbits and other hindgut fermenters

what is another name for cecotrophs?

night feces

what is coprophagy?

when rabbits re-ingest cecotrophs to absorb nutrients that were not fully digested the first time

in female rabbits, the uterine artery branches from the

vaginal artery

label these regions of the female rabbit external genitalia.

A - vulva

B - inguinal scent glands

C - anus

what are the reproductive tract differences in rabbits compared to small carnivores?

• 2 cervices

• abundant adipose in broad ligament

• numerous vessels in broad ligament

• lacking thick suspensory ligament

what do female rabbits lack in their repro tract?

thick suspensory ligament

what is this picture showing?

uterine left horn of rabbit

what is the arrow pointing to?

ovary in female rabbit

female rabbit is called a

doe

label these regions of the rabbit repro tract.

A - ovary

B - broad ligament (fat filled)

C - uterus (duplex)

male rabbits are called

bucks

label the parts of the male rabbit genitalia.

1. penis

2. inguinal fat pad

3. left testis

label the male rabbit internal genitalia.

A - urinary bladder

B - ductus deferens

C - cranial fat pad

D - testis

E - tail of epididymis

what is the natural habitat for chinchillas?

Andes Mountain and high elevation terrain

what is large on the chinchilla skull?

tympanic bulla

what do chinchillas have for hearing?

large pinna

yellow enamel color means

the enamel is thicker

what is this a radiograph of?

chinchilla skull

what type of teeth do chinchillas and guinea pigs have?

elodont and hypsodont

what does elodont mean?

incisor teeth, continuously growing throughout life of mammal

what does hypsodont mean?

high crowns to teeth; irregular occlusal surfaces, enamel crests and dentinal grooves, cheek teeth, both premolars and molars

chinchilla/guinea pig incisors are

elodont type

chinchilla and guinea pig premolars and molars are

elodont and hypsodont type

what types of teeth do gerbils, hamsters, mice, and rats have?

anelodont, elodont, and brachydont

what does anelodont mean?

premolars and molars, rooted, but not growing throughout life

what does brachydont mean?

low crowns to teeth; premolars and molars, enamel over entire occlusal surfaces

gerbil, hamster, mouse, rat incisors are

elodont and hypsodont type

gerbil, hamster, mouse, rat premolars and molars are

anelodont and brachydont type

what is important during castration of rat?

the fat pad → do not move it

label the abdominal viscera of the rat.

A - liver

B - intestines

C - stomach

D - spleen

E - kidneys

F - descending colon

G - uterus

the norway rat does not possess a

gallbladder

label the female rat pelvic cavity viscera.

A - uterus

B - ovary

C - urinary bladder

D - clitoral gland

what is this picture showing?

rat gravid uterus with multiple feti

what is this picture showing?

rat fetus with attached placenta

how many mammary glands does the norway rat possess?

6 pairs, 12 in total

label the mammary glands of the norway rat.

1. cervical

2. cranial thoracic

3. caudal thoracic

4. abdominal

5. cranial inguinal

6. caudal inguinal

lab rats have a high prevalence of

mammary gland neoplasia

what is this radiograph showing?

1. guinea pig fetus

2. guinea pig fetus

3. open pubic symphysis

when a guinea pig sow is close to parturition, what opens up?

pubic symphysis ligaments

what is relatively common in both guinea pigs and chinchillas?

dystocias (difficult or obstructed pregnancy)

when should a guinea pig sow have a litter?

prior to fusion of pubic symphysis by 6-9 months

what happens if a sow has a litter before the fusion of the pubic symphysis?

cartilage union forms and persists for life

what expands prior to parturition to allow passage of large feti?

cartilage union

what is this radiograph showing?

open/relaxed pubic symphysis of Guinea pig sow