Rabbits Flashcards
What are the general anatomical characteristics of lagomorphs?
- Herbivores
- 2 pairs upper incisors and 28 teeth
- Mandible united and narrower than maxilla
- Plantigrade hindlimbs
- No foot pads, toes and metatarsals hair covered
- Fuses coli
What are the lagomorph classes?
Lepus = rabbits, hares
Sylvilagus = cottontails
Ochotona = pikas
What are the similarities between rodents and rabbits?
- Herbivorous
- Diastema, gnawing and grinding compartments separated by lip folds
- Very large masticatory muscles
- Fast metabolism, acute hearing, smell, touch, obligate nose breathers
- Chisel like permanently sharp incisors for cutting
- Continually growing molars in guinea pigs, chinchillas, rabbits
- Loose jaw articulation, rotatory, forward and back jaw movements
- Caecotrophy in herbivores
- High fibre herbivorous diet absolutely necessary for dental health and gut mobility
Describe the anatomy of the head and neck.
- Tactile vibrissae
- Large ears – erect or floppy. Important for thermoregulation
- Philtrum like rodents
- Dewlap in doe. Unknown purpose, potentially for fat storage and does pull out fur from here to build nests
Describe the anatomy and importance of the ears.
- Thermoregulation as they do not contain any brown fat, do not sweat or pant
- 12% of body surface
- Highly visible central artery and peripheral veins
- Counter current arteriovenous shunt
- Unlike rodents possess no brown fat retain heat by shunting blood from ears to core
- Caudal auricular/marginal ear vein important venepuncture site or euthanasia site
What are the other venepuncture sites in the rabbit?
Jugular vein and saphenous vein (easier than jugular)
Describe the eyes.
- Wide visual field, except for just in front of the nose
- Upper lid is shorter and thicker than the lower
- Well-developed third eyelid but only moves 2/3 across the glove
- Low blinking 1-12 times per hours (Draize test)
- Extensive orbital venous plexus – care with enucleation and must ligate
Describe the lacrimal duct and its clinical significance.
- Only 1 lacrimal punctum situated on lower lid medial canthus
- Short canaliculus leads to lacrimal sac
- Lacrimal duct very tortuous, 2 sigmoid curves, encased in bone
- Exists at tiny nasal punctum
- Slow drainage due to lacrimal duct
- Prone to inflammation/dacrocystitis and blockage
Describe the mouth.
- Blind spot in front of the mouth
- Use lips and vibrissae for food discrimination and prehension
- Do not use incisor for prehension so can extract
- Philtrum extends to either side nares/harelip
Describe the digits.
- 5 digits front foot, 4 digits hindfoot
- Fur covered so no pads
- Pododermatitis, typically at the level of the hock
- Swift hopping movements – hindlimbs longer than forelimbs
- Plantigrade but digitigrade while running
Describe the mammary tissue.
- 2-5 pairs (have 8) nipples on the ventral thorax, abdomen and inguinal region
- Female only
Describe the scent glands.
- Territorial
- Submandibular scent glands, may be seen rubbing faces on surfaces
- Inguinal glands in spaces either side of anus dorsal to urogenital opening, can build up with caseous material which is normal unless excessive
- Anal glands
Describe the general osteology of rabbits.
- Hooked shaped suprahamate process in rabbits. Blunted in cats.
- Acetabulum of pelvis excludes pubis – ilium, ischium and os acetabulum
- Skeletal system light compared to body mass
- New Zealand white skeleton 6% while musculature 56% body mass
- Prone to spinal injury particularly at lumbosacral junction
Describe the skull.
Rabbit skull is larger than rodent skull, nasal terminates are exposed in the rabbit skull, is more domed shaped, has a characteristic diastema and large tympanic bulla (smaller than chinchilla).
State the rabbit dental formula.
2/1 0/0 3/2 3/3
Describe the rabbit dentition.
- 28 teeth
- All teeth aradicular and hypsodont
- 4 incisors: 2 pairs of upper incisors rudimentary incisors on lingual side – peg teeth
- Lower incisors lie between 2 pairs of upper at rest
- Enamel on labial side upper ad both sides lower incisors
- Diphyodont/2 sets of teeth – deciduous teeth lost in gestation
- Diastema
- Mandible united string fibrous symphysis
Describe the musculature of the head.
- Large masseter
- Smaller temporalis
- Masseter does not insert on rostral nose
- Flexible temporomandibular joint allows rostral, caudal and lateral movement
Describe the oral cavity.
- Oral cavity small
- Long tongue – lingual torus
- Narrow oropharynx
- Small glottis
- Intubation difficult
- Diastema
- Cheek folds separate incisor teeth from oropharynx
What may dental disease present as?
Dental disease can present as not eating/gut stasis or abscessation.
Why does dental disease in rabbits arise?
- All teeth aradicular/open rooted so grow continually
- Need to wear against each other to maintain shape
- Alteration can lead to malocclusion and elongated crowns
- Elongation of reserve crowns/roots penetrate bone and emerge through periosteum
- Periapical abscesses occur at sites of root penetration
What are the consequences of dental disease?
- Abscesses occur over sites of reserve crowns of molars in maxilla and mandible
- Also cause epiphora and dacrocystitis – reserve crowns impinge on nasolacrimal duct
- Digestive disorders
- Poor grooming
- Perianal matting
Describe the cardiorespiratory system.
- Both lungs lobated
- No septa dividing into lobules, so pneumonia is not localised
- Obligate nasal breathers. Mouth breathing in rabbits is a sign of respiratory distress.
Why is a high fibre diet important?
High fibre stimulates gut motility. Where gut motility is low, there can be over-digestion of food, increasing lactic acid and decreasing pH as a result. Affects gut microbes, causing damage to gut wall, excessive gas build up and ultimately toxins are absorbed in the body, which may lead to shock
What are the similarities and differences between rabbit and horse/cow digestive systems?
Quick fibre excretion like horses and cows
Bacteroides is main bacteria unlike lactobacillus in horse and cows