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Dr Mallon

biology and diseases of rabbits

recommended 
texts:  Exotic Companion Medicine Handbook for Veterinarians

rabbits - 
most of the time can tx like cats and will do ok.
one time she saw a pet 
rabbit with alopecia and the owner wanted to know what breed of rabbit it 
was. it was an NZW, most common research rabbit, so she knew - but owner 
was really only testing her! Other rabbits can be grouped by size - small 
rabbits are under 2 kg: dutch belted (american dutch chocolate, american 
dutch lilac), dwarf rabbit (Netherlands Dwarf white, sable point).
medium 
sized: 2-5 kg: NZW, NZR, Californian/Satin Californian
Large: > 5 kg: 
Flemish giants (sandy, steel grey); French lops (note ears)(broken 
pattern, solid pattern); english belted with black line down center of 
back; Golden Palomino; Himalayan; Champagne D'argent (?); Satin black, 
red, chinchilla, siamesse, chocolate; Rex - blue, black, silver martin. 


breeds not on test!

Rabbit ear has central artery and peripheral veins. 
marginal veins good for IV injection or blood sampling. for CBC/Chem, use 
the artery b/c you can get blood more quickly and easily, but you have to 
remember to hold it off longer and well. can put gauze sponge with 
paperclip on there for 1/2 hr.

females: dewlap - prominent skinfoled 
below neck. frequent site of moist dermatitis, caused by moisture from 
drinking or saliva. tx may require systemic abx or topical tx. males do 
not have the dewlap. 

dental formula - 28 teeth including 6 incisors and 
no canines. they have upper incisors behind which are a small pair of 
"peg teeth" which are the extra 2 incisors. also called wolf teeth. this 
is what makes them lagomorphs. rabbit teeth grow continuously, kept at 
normal length by wearing on each other. malocclusion is a problem. have 
to clip the teeth. you clip them once every 2-3 weeks or rabbit will 
starve. people notice rabbit might have feces stuck to the mouth or 
something. predisposition to malocclusion in NZW. can use dog toenail 
clippers or bone rongeurs (better). you don't have to use anesthesia, 
it's not painful. clip 1/4 inch above gumline between the teeth (gum 
outside of teeth is lower).

stomach - never empty. rabbits like horses 
and rats can't vomit. trichobezoars are common (hairball). self grooming 
can cause this. can result in partial/complete obstruction. signs: 
anorexia, lack of feces. 

fatty liver - appears yellow. hairballs can be 
dx by palpation and rads both survey and contrast; tx for hairballs 
aren't that successful - fresh pineapple juice has some success - canned 
won't work b/c canning inactivates papain. papain tablets aka papaya 
tablets can be used. don't use the contact lens formulation of enzymatic 
cleaner - too expensive. increased fiber in diet w/alfalfa cubes or 
non-frosted shredded wheat cubes, or hay. get owners to feed grass hay - 
highly recommended. metamucil - some success - mix with water, nutrical, 
feed via syringe. applesauce consistency. surgery is possible but rabbits 
often do not do well. 2 cases - one died, one lived. that one that lived 
was Andrea - 2 time hairball surgery survivor. the other rabbit died 
postop - Floppy - owner's name was Cox. "floppy" cox. bummer for her to 
present at rounds. after rabbit died, everyone said "Francine's rabbit 
died" and by the time that rumor got around, she was actually pregnant.


terminal ileum = sacculus rotundus - unique to rabbit. it prevents 
material in large intestine from moving into the ileum.  don't remove it!


hard to intubate rabbits - deep mouth, narrow mouth, tends to 
laryngospasm. clear 3-3.5 mm tube in NZW - no stylet.

one common 
respiratory dz - pasteurellosis - leading cause of morbidity and 
mortality in rabbits - prevalence 20-70%, p.multocida. spreads by 
aerosol, direct contact, many clinical signs:
nasal signs most common . 
probably first sign - serous to mucoid to mucopurulent oculonasal d/c. 
owners often do not notice this.
respiratory form - snuffles - thick 
nasal d/c, often wiped onto paws. 
abscess form - subcu abscess in dewlap 
or elsewhere. thick, caseous pus, toothpaste like. doesn't drain like cat 
pus does. do not use penrose drain. can get ascending infection and won't 
drain. tx like goat - lance largely and flush. too thick to drain. 
abscesses get huge. can ulcerate.
vestibular disease - otitis media, 
encephalitis.
pneumonia
septicemia
pyometra
orchitis

tx: nothing great. 
most recently most success with baytril 5 mg/kg BID, IM best. can use 
oral form. baytril recently changed tablets to now being liver or beef 
flavored which rabbits do not like. remind owner you aren't curing rabbit 
of pasteurella but are just treating signs. any stress can cause a 
recurrence. this is fatal and will eventually killrabbit.

no tricuspid 
valve in rabbits
sexing rabbits - not hard. young males have a pointed 
protruding genital opening, females have short slitlike opening. big fat 
rabbit, hard to tell. in intact male, can see inguinal pouches. best - 
extrude the penis to sex. can't sex by dewlap - not all breeds have, 
sometimes a fat male looks like he has one, etc. inguinal pouches obvious 
in a mature buck. female rabbits have duplex uterus, all parts are 
completely duplicated. each uterine horn has its own cervix. can maintain 
two separate pregnancies. can have pyometra in one horn and pregnancy in 
other. 

normal rabbit urine - yellow/brown and cloudy. this is not 
hematuria. this is normal rabbit urine. it is alkaline - pH > 8.0. the 
darkness is porphyrin pigment. use dipstick to check for hematuria.


feces - hard and soft (day and night). 80% are hard type. soft type are 
"cecotrophs" and copophragy/pseudorumination is normal for rabbits. 
rabbits eat 50-80% of feces mostly of soft type. sometimes called "night 
feces."
when rabbit has "diarrhea" ask owner if it always has it, or 
sometimes. if just sometimes theyare probably seeing some soft feces that 
rabbit isn't eating. 

rabbit neutrophils have granules that stain red 
instead of blue - "pseudoeosinophils" - important if doing CBC 
differential - ensure lab knows waht it is doing.

rabbits usually gentle 
but have powerful hind legs and sharp claws and scratches can really 
hurt. older bucks may bite. tend to struggle when picked up and can break 
own back or injure nerves/tendons. 

splay leg - caused by broken back 
-animal kicked with hind legs and broke his own back.

always handle 
rabbits gently but firmly; control hind leg movement. be aware of 
tendency for a scared rabbit to scream. pick rabbit up by grabbing large 
fold of loose skin over shoulders with one hand, support hindquarters 
with other hand. NEVER lift by the ears!. can hold by loose skin over 
shoulders, tucking head under elbow - football hold. wedge body b/w 
forearm and body, support by hand under rump. this is important. handling 
rabbits inappropriately can result in broken backs.

PE: towels help for 
restraint. alternatively older animals can be hypnotized via constant 
massage of masseter muscles while stretching on dorsum, or stretching 
with one hand around hips and one around back of neck using 
thumb/forefinger as hooks on mandible. 

restraining boxes - useful for 
single person who has to restrain rabbit for bleeding. control body/legs 
for manipulation of head/ears
cat bags are also excellent for restraining 
rabbits. 
the stainless steel rabbit restrainers are great; clear plastic 
ones also good. the opaque plastic one is not recommended.

puberty from 
4-12 mos depending on breed and size. 
doe should be taken to buck's cage 
to breed.
if not, she may turn around and bite his genitals.

breeding is 
entertaining. he mounts doe, 8-12 rapid movements, ejaculates, falls off, 
emits a loud cry. does are induced ovulators, occurs 12 hrs after 
copulation. gestation is 31-32 days: MAY BE ON BOARDS ***. palpable 
fetuses at 12-14 days. on rads by day 11. parturition is called 
"kindling" and usually takes under 30 minutes. young can be born 
hours/days apart if separate pregnancies. weaning 6-8 wks, rabbits 
usually only nurse once q 24 hrs for 2-3 minutes, 5-15 cc milk consumed. 
hand rearing formula in handout. people always want to raise orphan 
bunnies. they die when overfed or fed cow's milk. you should not feed too 
often. only 1-2 times daily!

Vit A deficiency causes hydrocephalus of 
babies and repro problems in adults. 

glaucoma - in 1% of all rabbits. 
enlarged eye with cloudy cornea, increased intraocular pressure.  not 
painful in rabbit and not treated. inherited in NZW. 

coccidiosis - 
common in rabbits - disease rare, infection can cause acute chronic or 
clinically silent disease. transmission fecal/oral. self perpetuating 
since coprophagic. in severe cases, can see rectal prolapse, watery 
diarrhea, mucus, blood. 

ear mites: most common and costly ectoparasite 
of rabbits. pruritic, cause scaling, crusty exudate, 2ry bacterial 
infections, head tilts. tresaderm works well. ivermectin also works well. 
tresaderm also has abx and steroid so often use that. mites have suction 
cups on feet.

Cheyletiella - fur mite - 15-60% of rabbits harbor this 
mite, usually nonpruritic facial alopecia with oily scale. can tx with 2 
inj ivermectin 10 days apart. feet have hooks.

ringworm is common in pet 
rabbits, is zoonotic, can dx w/woods lamp, culture. tx systemic 
griseofulvin; topical conofite. pet rabbit can present just as alopecia 
with no visible lesions. 

mucoid enteritis/enteropathy - one of most 
important causes of mortality in weanlings, characterized by passage of 
copious quantities of mucoid feces. cause is unknown, probably combo of 
bacteria, toxin, and dietary irregularity. low fiber diet will increase 
frequency of disease. rabbits must have a high fiber diet!!!! ***. this 
is a painful dz, causes bruxism and increased thirst. the feces look like 
KY jelly.

rabbits very sensitive to heat - hot, humid weather, poor 
ventilation can cause death esp of pregnant does. rabbits lie on side, 
breathe rapidly. if temp is over 85 and humidity is over 70%, as in 
summer here, rabbit can get heatstroke.

sore hocks: poor husbandry, 
rough wire in hutch. lesions on hocks. tx local cleaning, possible 
debridement, systemic abx. may have to bandage. 

most common tumor in 
rabbit is the uterine adenocarcinoma** 
locally invasive. does 
metastasize to lungs. only a 4% incidence in does under 3 yrs of age. 
spay before 3 yrs old to reduce risk! 25% of these cases often have 
cystic mammary glands, so ddx for cystic mammary glands is uterine 
adenocarcinoma.

vaccines: none. no good pasteurella vaccine - pig or 
sheep vaccine doesn't work. too many serotypes of pasteurella. in 
australia, there is a calicivirus causing severe nasal hemorrhage - they 
vaccinate for that there. 

this rabbit has deformed ears and is wearing 
an e-collar. e-collar is bad - cant turn around and eat his feces from 
his anus. now, you can use an e-collar post operatively but shouldn't use 
it longer than 2 weeks. if youmust, supplement with B vitamins. 




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