Chapter Twenty-One

1. Chapter Twenty-One Rabbits

2. ALAT Presentations Study Tips • If viewing this in PowerPoint, use the icon to run the show (bottom left of screen). • Mac users go to “Slide Show > View Show” in menu bar • Click on the Audio icon: when it appears on the left of the slide to hear the narration. • From “File > Print” in the menu bar, choose “notes pages”, “slides 3 per page” or “outline view” for taking notes as you listen and watch the presentation. • Start your own notebook with a 3 ring binder, for later study!

3. Rabbits • Serum antibody production • Drug screening • Pyrogen testing • Atherosclerosis (hardening of the arteries) • New Zealand white most commonly used in research. • Oryctolagus cuniculus

4. Handling & Restraint • Characteristically timid and excitable • Occasionally resist handling, endangering themselves & handlers. • Restraint method depends on type of procedure. • gentle but firm manual restraint • To remove a rabbit from a cage: • Grasp scruff of neck w/ 1 hand. • Support hindquarters & back w/ other hand. • Prevent rabbit from kicking w/ powerful hind legs. • Tuck head into crook of arm when carrying rabbit. • Never restrain by grabbing ears.

5. (Images) Rabbit Restraint

6. Handling & Restraint II • To examine head, mouth, teeth, & nostrils: • Grasp scruff of neck. • Supporting rump, turn rabbit upside down. • Tuck rump under arm that is securing scruff of neck; this gives the handler a free hand to examine. • Genital examinations or sexing can be done by holding rabbit on its back, in crook of the arm. • To restrain mechanically, use nylon or canvas bag, similar to type used to restrain cats. • for ear access for bleeding, intravenous injection, tattooing or treatment • Always have its rear limbs firmly controlled.

7. Physiological Data • Body temperature: 100.4°-104°F • Heart rate: 130-325 per minute • Respiratory rate: 30-60 per minute • Weight: adult, 2-6 kg; newborn, 30-80 gm • Water consumption: 100-600 ml / day or 50-100 ml / 1 kg body weight daily • Food consumption: 100-300 gm / day, or 50 gm / 1 kg body weight daily • Life span: 5–8 years Image from NIH Orientation

8. Physiological Data II • Feces: round pellets • Produce a special type of stool called night feces which is very soft & covered w/ thick mucus. • A normal part of digestive process, animal eats this stool to recycle protein, water & B vitamins. • Eating stool = coprophagy. • Urine: from clear red or yellow to a milky yellow • High amounts of minerals in rabbit urine account for this color.

9. Sexing • Male = buck, Female = doe • Buck - obvious external scrotum • Penis can be protruded by applying gentle pressure w/ thumbs and forefingers in front of & behind scrotum. • Sex of young determined by examining urogenital region. • Vulva of female may be seen as a pointed slit. • Prepuce of male appears as a round, doughnut-shaped opening.

10. (Images) Sexing: Female vs. Male

11. Breeding • Polygamous • Buck capable of mating w/ many females, may be bred up to five times a week. • A doe is taken to the buck’s cage for breeding. • Doe is territorial and may fight with a buck brought to her own cage. • In doe’s cage, the buck may show > interest in territory marking than in copulation. • Female does not have a true estrous cycle. • certain rhythmic periods during which they are receptive to bucks. • Doe does not ovulate until after mating. • = induced ovulation, a characteristic shared w/ cat & ferret

12. Birth and Weaning • Need nest box to give birth in. • wood shavings for nesting material • Doe will pull fur from herself to line nest. • Babies (kits) born blind, naked & helpless. • Parturition (giving birth) = kindling • Sexual maturity: 4-6 months • Estrous cycle: No regular cycle, receptive to breeding at 4-6 day intervals; induced ovulator • Gestation: 29-35 days; litter size: 4-10 • Weaning: 4-6 wks, eat dry food at ~ 3 wks of age

13. (Images) Nest Boxes

14. Behavior • Active, curious, explore objects in environment • Adept at escaping from unsecured cages. • When stressed or frightened: • bite or jump at handler • stomp hind feet • emit a high-pitched scream • Sensitive to noise & may react violently. • Toenails grow rapidly. • More active at twilight than during day. • Feed & drink water mostly in late afternoon & early evening, sleep during day.

15. Husbandry • Optimum temperature for most rabbits 61-72°F. • Lower temps reduce shedding. • Shed large quantities of hair. • Frequent cleaning of filters necessary. • Housed in cages w/ indirect bedding. • Lower half of sides, back & front of cage are solid. • Design prevents rabbit from spraying urine. • Spaces in cage floor must be small enough to prevent catching feet but large enough to allow fecal pellets to fall through. • Some cage racks are equipped with automatic flushing pans .

16. Husbandry II • Wash cages at least every 2 wks. • Empty & clean cage pans 2 or 3 x / wk. • Pans are usually treated with an acid solution prior to washing to remove urine scale. • Urine contains large amounts of minerals which remain on the pan surface when urine dries. • Commonly develop overgrown incisor teeth.

17. Diet • Fasten water bottles & feeders securely. • If a rabbit stops eating, check the water supply. • Train to use automatic watering valves. • Feed pelleted diets, from hopper-type feeders. • Tend to overeat if fed ad libitum, often fed only measured amounts of feed. • prevents obesity, promotes health & reduces waste • 1st sign of illness = loss of appetite.

18. Additional Reading Anderson, R.S. and A.T.B. Edney. Practical Animal Handling. Pergamon Press, Oxford, UK. 1991. Crow, Steven E., and Sally O. Walshaw. Manual of Clinical Procedures of the Dog, Cat and Rabbit, 2nd Ed. Lippincott-Raven, Philadelphia, PA. 1998. Harkness, J.E. and J. E. Wagner, The Biology and Medicine of Rabbits and Rodents. Williams and Wilkins. 1995. Hrapkiewicz, Karen, Leticia Medina, and Donald D. Holmes. Clinical Laboratory Animal Medicine: An Introduction, 2nd Ed. Iowa State University Press, Ames, IA. 1997. Laber-Laird, K., M.M. Swindle, P. Flecknell. Handbook of Rodent and Rabbit Medicine. Pergamon Press, Oxford, UK. 1996. Suckow, Mark A., and Fred A. Douglas. The Laboratory Rabbit. CRC Press, Boca Raton, FL. 1997. Weisbroth, S.H., R.E. Flatt, and A.L. Kraus, ( eds.) The Biology of the Laboratory Rabbit. American College of Laboratory Animal Medicine Series. Academic Press, Orlando, FL. 1995.