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Understanding Normal Rabbit Behavior

January 4, 2010 Leave a comment


Christal Pollock DVM, Dipl. ABVP-Avian

House rabbits can make wonderful pets, and more American households report owning rabbits than any other exotic mammal. Small animal veterinarians are being called upon to care for rabbits with increasing frequency, however approach to the pet rabbit often requires a significant shift in perspective for those used to dealing solely with cats and dogs. Normal rabbit behavior may be unfamiliar and rabbits possess few muscles of facial expression making them difficult to “read” when compared to cats and dogs.

Natural History

The first step in understanding rabbits is to understand the behavior of their wild predecessors. Free-ranging rabbits are communal, territorial animals that live in groups or warrens numbering anywhere from six to eight individuals up to several hundred animals. Rabbits live in burrows that make up a complex network of underground tunnels measuring up to 3 meters in depth and 45 meters in length. Rabbits spend most of the day in their burrows, coming out during early evening and morning hours.

Prey species behavior

Rabbits are prey species. Their survival in the wild depends on the ability to be alert and respond quickly, and this instinct has survived in the house rabbit. Rabbits possess acute senses of smell and hearing. Their first defense when danger is near is to be very still to avoid detection. If that doesn’t work, then rabbits will run using quick bursts of speed and rapid changes in direction.

Prey species like the rabbit tend to mask pain and discomfort, especially when frightened. Recognition and management of pain is crucial since pain in the rabbit may lead to gastrointestinal stasis, or even shock and death.
• Signs of fear in the rabbit include the body flattened in a crouched, motionless position with the feet tucked underneath and the head extended. Ears are often tucked tightly against the head, and the eyes may bulge. The clinician should respond by speaking softly, moving slowly, and approaching the rabbit at eye level.
• Signs of pain may include: anorexia, lethargy (reluctance to move, decreased interest in the environment), teeth grinding in a slow, loud crunching fashion, bulging, often unfocused, eyes, and a hunched posture with the head in an elevated, extended position. Rabbits may lick excessively or even pluck hairs over a painful area or seek hiding places. Respirations may be rapid and shallow.

Normal sounds and actions

Although comparatively silent, rabbits do make a variety of sounds.
• “Purring” is a sound of contentment made when the rabbit is getting a good petting or very tired. The teeth click softly, the head trembles, and the whiskers quiver.
• “Honking” or “oinking” sounds are made in courtship or to gain food or attention.
• Whimpering or low squealing are fretful noises made by a rabbit that does not want to be picked up.
• Finally, but most importantly for veterinarians, some rabbits “talk” by making wheezing or sniffing sounds.
These sounds may be distinguished from congestion by being heard inconsistently and only in conjunction with social interaction.

Interaction with a house rabbit tends to make one more one adept in non-verbal communication.
• A sign of possessiveness is “chinning” when the rabbit rubs its chin on items or people.
• One of the least subtle behaviors is called the “happy hop” or “binky”. The rabbit will jump into the air with the head going in one direction and the rest of the body going in the other direction. “Binkies” appear to denote pure joy. A video clip demonstrating the “happy hop” may be found at: http://www.thebunnyshed.co.uk/TheFAQ.htm.

Age and Breed

Not surprisingly, juvenile rabbits tend to be energetic and extremely inquisitive. Owners are most likely to complain of chewing and other “problem behaviors” in this age group. After one year of age, most rabbits become more sedate and predictable. Rabbits are considered geriatric after 6 to 7 years. At this age they generally sleep more and move more slowly. There are also breed differences in behavior. Large rabbits such as the New Zealand white tend to be calmer than smaller rabbits like the Netherland Dwarf.

Husbandry

Proper house rabbit care is based on normal rabbit behavior:
1. Most rabbits tend to urinate and defecate in the same place each time. This habit of picking a latrine spot means that most rabbits are easily litter trained.
• Place the litter pan in one area of the cage or just outside the cage door, and place many boxes around the room. Initially, limit the rabbit to a small space and limit the amount of time for the rabbit to roam outside of its cage. Placing hay or treats in the litter box may also attract the rabbit to the pan.
• A trained rabbit may urinate outside of its pan if it needs to mark territory due to a stressful event, or with urinary tract disease.
• Rabbits will also mark territory by depositing hard fecal pellets. This behavior is most intensely practiced by adult intact males, however even castrated rabbits mark new areas in this manner.

2. To feel comfortable and safe, rabbits like to go on, under, beside, or beneath objects.
• Boxes are often a favored item, however few rabbits will use a box with only one hole in it. After all, a predator can trap you if your burrow has only one opening.
• Females often have a stronger urge to burrow than males.

3. Rabbits have an instinctive urge to chew.
• “Bunny proofing” prevents property destruction and protects rabbits from harm. Avoid rooms with wall to wall carpet, low shelves, high numbers of electrical cords, and/or books or plants within 2 feet of the floor. Protect exposed cords using polyethylene tubing or armoured cable.
• Provide safe and fun chewing and digging alternatives free of chemicals or varnishes such as rice matting and willow bark. Many rabbit toys focus on the need to chew. The House Rabbit Society [link to http://www.rabbit.org/faq/sections/toys.html%5D has an excellent recommended toy list.

4. Rabbits are crepuscular creatures that normally rest and sleep during most of the day, and are most active at dusk and dawn.

5. Many experts on house rabbit care agree that most rabbits are not meant to live in solitude away from members of their own kind.
• The need for companionship can only be met partially by a human, although rabbits may display affection and acceptance for their owners through grooming.
• Signs of loneliness in rabbits commonly include boredom, depression, and withdrawal. Destructiveness and hyperactivity are seen in some smaller breed rabbits.
• Despite their need for companionship, introductions can prove challenging, and some aggression should be expected. Introducing two intact rabbits of any gender is likely to result in fighting, breeding behavior, or both. Introductions may be least stressful when they involve neutered adults of opposite sexes. Strive to match ages, however mixing breeds often works well such as a dwarf rabbit placed with a large breed rabbit. Introduce rabbits for short 20-minute sessions in a neutral territory.

Sexual Behavior

Puberty occurs just after the maximal rate of growth, with small breeds reaching puberty between 3.5 to 5 months of age and large breeds maturing at 5 to 8 months. Does mature earlier than bucks. Signs of sexual maturity may include aggression, territoriality, circling and spraying urine, and frenzied digging. Males show constant libido, attempting to mount cage mates, while females tend to behave quite aloof. Rabbits are induced ovulators, with potentially long periods of estrus. If mating does not occur, ovarian follicles regress and new follicles mature, therefore sexual behavior does not go away in the rabbit unless the animal is neutered or bred.

Spaying and neutering improves litter box habits and reduces territorial aggression, mounting, and spraying. The average time for negative sexual activity to lessen significantly after surgery is 2 weeks, and activity may be completely gone by this time in females. It generally takes 2 months until sexual activity is completely gone in males, and cessation of sexual activity may take 4 to 8 months in larger breeds.

Conclusion

The approach to a prey species like the rabbit often calls for a profound paradigm shift for clinicians used to dealing only with cats and dogs. The ability to truly understand rabbits will improve the clinician’s ability to not only diagnose and treat medical conditions, but also help owners love and care for their pets.

References

American Veterinary Medical Association. US Pet ownership and demographics sourcebook. Schaumburg, IL: AVMA 2002.

Bays TB, Lightfoot TL, Mayer J. Exotic Pet Behavior: Birds, Reptiles, and Small Mammals. WB Saunders, St. Louis, 2006.

Bradley T. Rabbits: Understanding Normal Behavior. Exotic DVM 2(1): 19-24, 2000.

Checchi MJ. Are You the Pet for Me?: Choosing the Right Pet for Your Family. St. Martin’s Press, New York, 1999.

Davis SE, Demello M. Stories Rabbits Tell: A Natural and Cultural History of a Misunderstood Creature. Lantern Books, New York, 2006.

Harriman M. House Rabbit Handbook: How to Live with an Urban Rabbit, 4th edition. Drollery Press, Alameda, 2005.

Lockley R. The Private Life of the Rabbit. Avon, 1975.

Mayer J. Natural history of the rabbit (Oryctolagus cuniculus). Exotic Mammal Medicine and Surgery. p.6

McBride A, Bondarenko N. Why Does My Rabbit…? Souvenir Press, London, 2003.

Isbell C, Pavia A. Rabbits for Dummies. For Dummies, 2009.

Quesenberry KE, Carpenter JW. Ferrets, Rabbits, and Rodents: Clinical Medicine and Surgery. WB Saunders. St. Louis, Missouri, 2005.

Thompson, Henry. The European Rabbit: The History and Biology of a Successful Colonizer. Oxford University Press, New York, 1994.

Categories: Behavior, Rabbit

Cool Recent Abstracts

April 30, 2009 Leave a comment

SMALL ANIMAL

Intracranial Arachnoid Cysts in Dogs

from Compendium by Curtis W. Dewey – Veterinary Answers Consultant, Peter V. Scrivani, Ursula Krotscheck, Sofia Cerda-Gonzalez, Kerry Smith Bailey, Dominic J. Marino

Intracranial arachnoid cyst (IAC) is an infrequently reported developmental disorder seen primarily in small-breed dogs. It usually occurs in the caudal fossa, in the region of the quadrigeminal cistern. Although still considered uncommon, IAC is being recognized more frequently in veterinary medicine, coinciding with the increased availability of magnetic resonance imaging. In this article, clinical information from previously reported cases of canine IAC is combined with additional case information from our hospitals. Similar to IAC in people, it is thought that canine IAC is often an incidental finding. When IAC is responsible for neurologic disease in dogs, generalized seizures and cerebellovestibular dysfunction are the most common clinical presentations. Medical therapy of IAC focuses on management of increased intracranial pressure and seizures, if the latter are part of the clinical complaints. Surgical therapy of IAC involves either cyst fenestration or shunting the excess fluid to the peritoneal cavity.

Peripheral Nucleated Red Blood Cells as a Prognostic Indicator in Heatstroke in Dogs

from JVIM by I. Aroch, G. Segev, E. Loeb, Y. Bruchim

Heatstroke in dogs is often fatal and is associated with a high prevalence of secondary complications. Peripheral nucleated red blood cells (NRBC) occur in dogs with heatstroke, but their association with complications and the outcome is unclear. Peripheral NRBC are common in dogs with heatstroke and have prognostic significance. Forty client-owned dogs with naturally occurring heatstroke. Prospective, observational study. Dogs were followed from presentation to discharge or death. Serum biochemistry and coagulation tests were performed at presentation. CBC and evaluation of peripheral blood smears were performed at presentation and every 12 hours. The relative and the absolute NRBC numbers were calculated. Presence of NRBC was observed in 36/40 (90%) of the dogs at presentation. Median relative and absolute NRBC were 24 cells/100 leukocytes (range 0[ndash]124) and 1.48 × 103/[mu]L (range 0.0[ndash]19.6 × 103/[mu]L), respectively. Both were significantly higher in nonsurvivors (22) versus survivors (18) and in dogs with secondary renal failure and DIC versus those without these complications. Receiver operator curve analysis of relative NRBC at presentation as a predictor of death had an area under curve of 0.92. A cut-off point of 18 NRBC/100 leukocytes corresponded to a sensitivity and specificity of 91 and 88% for death. Relative and absolute numbers of peripheral NRBC are clinically useful, correlate with the secondary complications, and are sensitive and specific markers of death in dogs with heatstroke, although they should never be used as a sole prognostic indicator nor should they replace clinical assessment.


Relationships between Low Serum Cobalamin Concentrations and Methlymalonic Acidemia in Cats

from JVIM by C. G. Ruaux, J. M. Steiner, D. A. Williams

Serum cobalamin concentrations below reference range are a common consequence of gastrointestinal disease in cats. Serum cobalamin [le] 100 ng/L is associated with methylmalonic acidemia. To determine the prevalence of cobalamin deficiency, defined by elevated serum methylmalonic acid (MMA), in cats with serum cobalamin [le] 290 ng/L, and the optimum serum cobalamin concentration to predict cobalamin deficiency in cats. Residual serum samples (n = 206) from cats with serum cobalamin [le] 290 ng/L. Retrospective, observational study. Serum cobalamin and folate were measured with automated assays. Serum MMA was determined by gas chromatography-mass spectrometry. Cobalamin deficiency was defined as serum MMA > 867 nmol/L. Sensitivity and specificity of serum cobalamin concentrations [le]290 ng/L for detecting MMA > 867 nmol/L were analyzed using a receiver-operator characteristic curve. There was a negative correlation between serum cobalamin and MMA concentrations (Spearman’s r=[minus]0.74, P 867 nmol/L. No significant difference in serum folate concentrations was detected between affected and unaffected cats. Elevated MMA concentrations, suggesting cobalamin deficiency, are common in cats with serum cobalamin [le] 290 ng/L. Cobalamin deficiency is clinically significant, and supplementation with parenteral cobalamin is recommended for cats with gastrointestinal disease and low serum cobalamin concentrations.

For more on MMA in human beings, click here.

Small Mammals
Single- and multiple-dose pharmacokinetics of marbofloxacin after oral administration to rabbits

From AJVR by James W. Carpenter, MS, DVM; Christal G. Pollock, DVM (VETERINARY ANSWERS CONSULTANT); David E. Koch, MS; Robert P. Hunter, PhD

Objective—To determine the pharmacokinetics of marbofloxacin after oral administration every 24 hours to rabbits during a 10-day period.

Animals—8 healthy 9-month-old female New Zealand White rabbits.

Procedures—Marbofloxacin (5 mg/kg) was administered orally every 24 hours to 8 rabbits for 10 days. The first day of administration was designated as day 1. Blood samples were obtained at 0, 0.17, 0.33, 0.5, 0.75, 1, 1.5, 2, 3, 4, 5, 6, 8, 12, and 24 hours on days 1 and 10 of marbofloxacin administration. Plasma marbofloxacin concentrations were quantitated by use of a validated liquid chromatography–mass spectrometry assay. Pharmacokinetic analysis of marbofloxacin was analyzed via noncompartmental methods.

Results—After oral administration, mean ± SD area under the curve was 10.50 ± 2.00 μg·h/mL and 10.90 ± 2.45 μg·h/mL, maximum plasma concentration was 1.73 ± 0.35 μg/mL and 2.56 ± 0.71 μg/mL, and harmonic mean terminal half-life was 8.0 hours and 3.9 hours for days 0 and 10, respectively.

Conclusions and Clinical Relevance—Marbofloxacin administered orally every 24 hours for 10 days appeared to be absorbed well and tolerated by rabbits. Administration of marbofloxacin at a dosage of 5 mg/kg, PO, every 24 hours is recommended for rabbits to control infections attributable to susceptible bacteria.

EQUINE
Risk Factors for Equine Postoperative Ileus and Effectiveness of Prophylactic Lidocaine

from JVIM by S. Torfs, C. Delesalle, J. Dewulf, L. Devisscher, P. Deprez
Postoperative ileus (POI) is a frequent and often fatal complication of colic surgery. Reliably effective treatments are not available. To determine risk factors and protective factors associated with POI, and to assess the effect of lidocaine IV on short-term survival. One hundred and twenty-six horses that underwent small intestinal colic surgery and that survived for at least 24 hours postoperatively. Retrospective cross-sectional study. The association of 31 pre-, intra-, and postoperative variables with POI and the association of lidocaine treatment with short-term survival were investigated. Associations were evaluated with univariable logistic regression models, followed by multivariable analysis. Significant associations of high heart rate (odds ratio [OR] = 1.05, 95% confidence interval [CI] 1.03[ndash]1.08), the presence of more than 8 L of reflux at admission (OR = 3.02, 95% CI 1.13[ndash]8.02) and the performance of a small intestinal resection (OR = 2.46, 95% CI 1.15[ndash]5.27) with an increased probability of POI were demonstrated. Prophylactic lidocaine treatment was significantly associated with a reduced incidence of POI (OR = 0.25, 95% CI 0.11[ndash]0.56). Lidocaine treatment was also significantly associated with enhanced short-term survival (OR = 0.30, 95% CI 0.09[ndash]0.98). The variables associated with an increased risk of POI can be useful in identifying horses at risk of POI and in providing a more accurate prognosis. The results are supportive for lidocaine IV as an effective prokinetic treatment after small intestinal colic surgery.