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Contrary to assertions that one should minimize contact (e.g., Evans, 1983; Buglass Hiss, 1988; Reese,1994), I have found that 'taming' wild infant rabbits during the first two days following admittance with frequent handling is a critical component of their survival during rehabilitation. Piver (1991) similarly advocates a 'touch' approach to rehabilitating infant cottontails.

                          However, upon introduction  

                      of solid food and within a few days,  

                 the rabbits typically develop diarrhea and  

                          die in a matter of hours  

When not handled in this way, wild baby rabbits become stressed every time a human comes near. Thus, they have a low likelihood of survival in captivity. Based on my experience, I do not recommend that bunnies be kept rehab centers, but rather be fostered out to a home where they will have only one caregiver, and where stress factors can be dramatically reduced.Diet-associated diarrhea has proven more difficult to manage,especially when rehabilitation begins with baby rabbits whose eyes have not yet opened.Diarrhea commonly caused by "overfeeding of nutritional inadequate diets" (Evans, 1983) can be circumvented through carefully monitoring the animal's stomach during feeding and by using a milk-replacer formula combination that closely reflects the mother rabbit's milk in gross nutritional composition, as described in this article. However, upon introduction of solid food and within a few days, the wild baby rabbits typically develop diarrhea and die in a matter of hours, most likely from enterotoxemia caused by pathogenic bacteria in their gut (Cheeke, 1987). Efforts to manage this problem have been used with limited success by using antibiotics and/or by providing 'harmless' bacteria (e.g., Lactobacillus; Bene-bac®, etc.) to prevent colonization of the gut with pathogenic microbes and inoculate needed gut flora (e.g., Buglass-Hiss,1988; Reese, 1992, 1994).In fact, Evans (1983) recommends against the "blanket use" of antibiotics with cottontails. In my experience, none of these techniques has worked with rabbit babies who were separated from their mother prior to their eyes opening. Weaning-onset mortality was 100 percent.This article presents a novel approach to preventing weaning-onset diarrhea in cottontail rabbits, based on knowledge of the biology of these animals. (Please see part two - covering weaning to release in the Winter 2000 issue of Wildlife Rehabilitation Today).It is well-known that adult rabbits engage in coprophagy, in which they produce and consume a special type of "soft" or "night" feces, separate from the excretion of their "regular" hard pellets (Cheeke, 1987). (The soft feces are more technically called cecotropes or caecotrophs, and for brevity I will hereafter refer to these as 'CTs.')In the rabbit gut, specific microbes act on food in the cecum, a sac-like structure at the juncture of the small and large intestines. This fermented, bacteria-laden material is coated with mucous. It is voided to produce the CTs. When consumed, CTs provide additional nutrients, including protein, minerals and certain vitamins (Cheeke, 1987).Ingestion of CTs also provides a continual supply of the appropriate microbes that are necessary for proper functioning of the rabbit's gut (Cheeke, 1987). My observations suggested that baby rabbits obtain their gut flora needed to process solid food via eating some of their mother's CTs. Thus, the protocol described below provides CTs to baby rabbits prior to weaning onto solid foods. I have used this technique since 1987 to avoid weaning-onset diarrhea during successful rehabilitation of dozens of baby cottontails (Sylvilagus floridanus) and marsh rabbits (S. palustris).

                             I have used this technique  

                          since 1987 to avoid weaning-onset  

                       diarrhea during sucessful rehabilitation  

                           of dozens of baby cottontails  

My protocol for successful rehabilitation of these animals involves handling/ taming of the babies, which results in wild baby rabbits that are calm in my presence. I am the only person caring for the babies. The only other person that they ever see is my spouse; thus they remain frightened of others, as they should be. Upon release, they "wild out" without any problem and yet remain unafraid of me. This allows me to closely monitor their post-release progress, as they remain near our home on wooded acreage, where we provide specially-constructed brush piles and other hiding places.As evidence of the success of this rehabilitation protocol, I have witnessed several of my released rabbits reproduce. They also have much better than average survival - two to six years - in this 'wild' setting despite the presence of various predators, including hawks, owls, foxes and raccoons.I will address weaning, including the use of CTs to prevent diarrhea, as well as caging and release, in the Winter 2000 issue of Wildlife Rehabilitation Today.

During intake assessment of a wild baby rabbit, the primary concern is for its safety.It is a very rare bunny that ever tries to bite. Rabbits' main method of defense is kicking with their hind legs. Though they are capable of inflicting significant scratches, the main danger is to themselves, in that improper holding can result in a fractured spine from the kicking, and also from a fall.Therefore, hold the bunny securely by placing a forefinger of one hand over its ears and forehead with the other fingers and thumb over its shoulders and forelegs. Use your other hand to support and secure its hind legs and rump. Always be alert; bunnies have an uncanny way of relaxing, tending to cause the handler to relax, and then they try to leap out of your grip. Quickly assess the bunny for life threatening conditions that would require emergency care: severe bleeding, shock, difficulty or cessation of breathing, hypothermia or hyperthermia, brain or spinal injury, poisoning, seizures, vomiting, severe burns, severe dehydration, etc. If you are not familiar with protocols for dealing with these problems, see the International Wildlife Rehabilitation Council Basic 1AB course book or the National Wildlife Rehabilitators Association Principles of Wildlife Rehabilitation (1997) manual for details. Or you can consult an experienced wildlife rehabilitator orveterinarian.Make a determination of hydration status by pinching the skin together into a tent on the animal's back at shoulder blade level, and time how long it takes for it to become flat again. Less than one second indicates five percent dehydration; greater than five seconds is severe. No return requires veterinary emergency care.All animals are considered to be mildly dehydrated upon admission, therefore begin administering a rehydration solution (Pedialyte®, Normosol® or lactated Ringer's) every 30 minutes until a normal hydration level is achieved. If the baby appears to be stressed, do not proceed with the physical exam at this time. Instead, stabilize the animal by treating its emergency conditions and place it in a warm incubator in a darkened, quiet area free from human activity and potential predators so that it can calm down, settle in and warm to its normal body temperature (101-103 degrees F).The first step in the physical examination is to observe the baby in the holding container for any additional signs of problems. Examine it from head to tail - does it appear normal, maintain a normal body posture, move correctly, use all limbs, behave naturally, etc.? Use your senses of sight, smell, and hearing when conducting a physical exam. Record the information on a standard physical exam form. Any abnormalities should by appropriately addressed; discussion of these details is beyond the scope of this article.Note that babies that do not have their eyes open can be held and comforted soon after intake. Older babies with their eyes open may require several hours or days to become accustomed to you and to its new surroundings before taming down. As you regularly feed the baby, clean its cage and talk softly to it, you will notice that it will soon become used to you and your hands.Also, it is important to raise more than one baby together; these are social animals when they're babies and need to have playmates and the comfort of cuddling with others.

Wild Babies under two-and-one-half weeks of age should be housed in an incubator. To build an inexpensive, efficient and safe incubator, use a plastic see-through sweater box; drill 1/4" holes 3" apart in rows spaced every 3" across the top. The heat source is a seven-watt night light fixture with the shade removed, plugged into an extension cord and placed into the bottom of a wide- mouth pint canning jar or a glass peanut butter jar. Place the jar in a fuzzy athletic sock, turned inside out; close the sock at the top of the jar with a "twist em" and again at the top of the sock onto the cord. Pin a tent made with sweatshirt material on the side of the jar. Line the incubator with a baby receiving blanket or tee shirt. Place the heater jar in one end of the incubator, making certain there is room all around it for the baby to move without getting stuck.This provides a nice 'warm fuzzy' for the baby to cuddle up to and a cozy cover, almost like Mom! If the room is too cool, you might need to place a towel over some of the holes in the incubator top to hold in more heat, but DO NOT cover the holes over the heating jar or it will get too hot.Another heat source, but much more expensive both to purchase and to use (150 vs. seven watts), is a heating pad placed under one end of the incubator, set on low.

After the wild baby rabbit is fully hydrated, palpate and visually check the stomach for remaining mother's milk.Once the stomach is mostly empty, begin the transition to full strength formula, using the following schedule.(Note that there should be a total of at least nine feedings with pre-mixed formula diluted with Pedialyte® before introducing full strength formula). 

Pre-mixed rabbit formula 1	Pedialyte�	Give enough to lightly fill stomach every:
1 part	3 parts	1/2 hr (for 3 feedings)
1 part feedings	1 part	1 hr (for 3 feedings)
3 part feedings	1 part	2 hr feedings (for 3-4 feedings)

1 The pre-mixed rabbit formula used here is given below. Note that the powdered formula is mixed with water first, and then diluted with Pedialyte®. Do not make up the powdered formula with Pedialyte®. An established formula that comes close to matching the milk of mother cottontails in gross nutritional composition (Marcum, 1997) is: 

Zoologic 42/25� or KMR�	1 part
Zoologic 30/55� or Multi Milk�	1 1/2 parts
Water (distilled or boiled)	2 parts

Other published combination formulas are too protein deficient; even this formula is somewhat lacking in protein. Evans (1983) recommends the addition of commercial protein supplements, although I am not aware of any specific work that has been done to establish this method.Neither Esbilac® nor KMR® should be used alone; Esbilac is very protein deficient and too high in carbohydrates. KMR is deficient in fat and excessively high in carbohydrates, which contributes to diarrhea.Mix only enough powder and water to provide formula for a day's worth of feeding, and keep the unused portion refrigerated to minimize bacterial growth. The recommended feeding utensil is a 1cc syringe with a Catac® nipple, or a nipple made from cutting a 1 1/2 inch piece of #10 or #12 size gastric tube.Babies that have not yet opened their eyes have an essentially sterile gut system, which is maintained by an interaction with the high fatty acid content of the mother's milk (Cheeke, 1987). We cannot duplicate this using existing formulas, and thus it is very important that we do not introduce any bacteria when feeding. Therefore, it is necessary to wash your hands thoroughly and to sterilize all feeding equipment by placing in boiling water before each feeding.When refrigerated, the formula becomes very thick and will need to be spooned out of the storage container. Heating it achieves a more liquid consistency. Warm only the amount of formula that you will feed at one feeding and discard any leftovers. Place the formula in a sterilized medicine dose cup or 35mm film canister and heat it briefly in a microwave or in hot water until it is close to the baby's body temperature. It should feel very warm to your wrist. You should keep the formula warm by immersing its container in a baby food jar of heated water.Hold the baby rabbit in an upright position for feeding. Babies whose eyes have not yet opened should be picked up and laid back in your hand at a 45 degree angle. If the animal resists feeding, it can be encouraged by lightly coating the nipple tip with Nutri Cal® or baby food (e.g., banana or sweet potato flavors). Feed slowly and pay close attention to the crease between the baby's lip and nose - wipe away any milk that goes up toward the nose. Most babies ( before their eyes open) will suck readily on the nipple; older ones may just lick formula off the nipple.

                             Rather than following  

                           published feeding charts,  

                           observe and palpate the  

                             stomach as you feed.  

Unlike squirrels, bunnies are not prone to overeating. However, it is important not to overfeed, as that will cause diarrhea. Rather than following published feeding charts, observe and palpate the stomach as you feed. It should be slightly rounded out and slightly firm, but never hard or taut. Babies that do not have their eyes open are fed every three hours and with much smaller amounts than what you will see in published feeding charts.Many articles on rabbit care state that babies are only fed once or twice a day by their mothers andthus that we should feed on a similar schedule. However, I recommend more frequent feedings, for two reasons. First, rabbit mothers in the wild may actually feed more often - once or twice during the night, as well as at dawn and dusk (Harrison & Harrison, 1985). Second, substitute milk formulas are digested much more rapidly than rabbit milk, which due to its acidity, forms a thick curd in the baby's stomach and digest slowly over several hours.Adjust the feeding schedule so that the baby's stomach is mostly empty before feeding again. Some bunnies digest faster than others.Babies with eyes closed must be stimulated to urinate and defecate. Some may defecate on their own but you should stimulate them after each feeding.Bunnies that are accustomed to being held will allow stimulation for elimmination long after their eye have opened. This allows you to closely monitor the character of both urine and feces, and keeps the cage cleaner.

Always be on the alert for the first sign of mushy feces, and make corrections, such as by reducing the amount or frequency of formula feeding, changing or reducing the amount of weaning foods given, reducing the stress level, etc. Mushy feces may also indicate a need for administration of another couple doses of CTs (this is be covered more fully in part two in the Winter 2000 issue of Wildlife Rehabilitation Today).Babies whose eyes have yet to open should be weighed every other day, as a consistent loss in weight is a sign of a problem. Use this link to go to Diarrhea Free Wild Baby Rabbit Care Part 2 .

Buglass Hiss, A. 1988. Rehabilitation notes: Cottontails: (Sylvilagus floridanus). Wildlife Journal. 11 (#2): 7-12. IWRC, Suisun, CA. 

Cheeke, P. R. 1987. Rabbit Feeding and Nutrition. Academic Press, Orlando.

Evans, R. 1983. Management of diarrhea related problems in cottontails. Wildlife Journal. 6 (#4); 13-16. IWRC, Suisun, CA.

Harrison, K. & G. Harrison. 1985. America's Favorite Backyard Wildlife. Simon & Shuster, New York.

Marcum, D. 1997. Mammal nutrition: Substitute milk formulas Part III Species-specific daily feeding charts for selected North American wild mammals, pp. 325-353 in "NWRA Principles of Wildlife Rehabilitation;" A. T. Moore & S. Joosten. NWRA, St. Cloud, MN.

Piver, E. M. 1991. Multidisciplinary management of the nursing eastern cottontail (Sylvilagus floridanus), pp. 23-33 in D. R. Ludwig (ed.), NWRA Wildlife Rehabilitation, Vol 9. Burgess Printing Co., Edina, MN.

Reese, E. 1992. Cottontail feeding problems: Part II "The big D." Wildlife Journal. 15 (#4): 7-11, IWRC,

Suisun, CA.

Reese, E. 1994. Orphaned eastern cottontail care. National Wildlife Rehabilitators Assoc. Quarterly 12

(#3): 1-5.

Robbins, C. T. 1983. Wildlife Feeding and Nutrition. Academic Press, Orlando, FL.

              Copyright 1999-2000 Lou Rea KenyonAll rights reserved