Rabbits, Winter and Hypothermia

 

 

 

 

Environmental conditions related to temperature play a critical role in the survival of all warm blooded animals.  Different species have evolved the ability to survive one extreme or the other on the temperature scale providing suitable water, food and shelter sources are available.  However, there will always be an optimum range in which a species will thrive and reproduce best.  For no animal is that any truer than for the rabbit.

 

When we see a wild rabbit during the cold of winter, it is usually on the run from one place to another.  What we don’t see is that during the biter cold, the wild bunny stays warm and comfortable in an underground den where it is well insulated from the extremes of wind and cold.  Cold drafts are one of the most common weather related killers of rabbits; the underground den is a perfect shelter.  The wild rabbit will have filled its nest with grass and straw that works as a perfect insulator, trapping the rabbit’s body heat and thus maintaining its body temperature in the normal range.

 

For the breeder of domestic rabbits, winter weather presents certain challenges that can require specific attention.  It is important for the breeder to have a full understand of how the environments of heat and cold effects his rabbits and when temperature can pose serious problems requiring immediate attention.

 

ENVIRONMENTAL CONCERNS:

 

Rabbits by nature are cold weather animals.  They can easily tolerate temperatures at 32 degrees Fahrenheit or lower providing they have shelter from the wind and wet conditions.  They have trouble tolerating temperatures above 85 degrees Fahrenheit and must be kept out of direct sun light during the summer months.

 

During the winter, rabbits will need a fresh supply of ice free water at least twice a day.  Water is necessary to aid in the adequate digestion of feed to provide the energy necessary to resist the stress of cold weather.

 

A rabbit burns more calories keeping and maintaining its body temperature during the cold winter.  It is important however, not to overfeed but to instead feed enough to maintain only.  Rabbits that gain weight over the winter will have a harder time breeding successfully the following spring.

 

The normal body temperature for a rabbit is between 101.5 and 103 degrees Fahrenheit. There are rabbit breeders in Fairbanks Alaska where most do not have heated barns. Their recommendation is to provide plenty of hay and straw for bedding, an ample supply of ice free water, a slightly increased amount of food, and of great importance, the avoidance of drafts.  In all cases, it is the lack of protection from the winter winds that pose the greatest degree of stress on rabbits. A nesting box with a thick layer of dry straw or hay will provide enough insulation to allow the rabbit to maintain its body temperature if there are no cold drafts.

 

Great care needs to be taken when traveling during the winter time to avoid extreme temperature changes in their environment.  If rabbits are carried inside the car, make sure that hot air from the car’s heater is not directed onto them.  If the rabbits are carried in a trailer or the back of a pickup truck, check that the animals have sufficient ventilation without being in the path of a cold air stream.  At speeds of 60 miles per hour on a day when the air temperature is -5 degrees, the wind entering through an open window or leak in the side wall of a vehicle will have a chill factor equal to a temperature of 63 degrees below zero.  If this air is directed onto an unprotected rabbit, the animal will quickly start to loose body temperature.  When a rabbit’s temperature drops below 100 degrees Fahrenheit, it will be in extreme danger unless the loss of body temperature is reversed. 

 

Hypothermia is defined as that point when the natural ability to regain or maintain a normal body temperature is lost.   A rabbit is in danger of developing hypothermia once the animal’s temperature drops below the 100 degree rectal temperature threshold.  Once this threshold is passed, the rabbit’s internal body mechanisms will no longer be capable of producing enough internal heat to replace the heat that is being lost to the environment.  As more core body heat is lost, the rabbit will slowly enter a kind of suspended animation were the normal functions of breathing and heart rate will slow down.  The body’s ability to produce heat energy will be further compromised as the core body temperature drops further until most metabolic activity will have slowed to undetectable levels.  In many cases, the animal will survive if external heat is applied and the core temperature is returned to normal.  In extreme cases, external appendages, especially the ears, may cool to the point where freezing of the tissue occurs resulting in irreparable damage.  The condition called hypothermia is broken down into three levels based on rectal body temperature; Mild 86 to 89 degrees Fahrenheit, Moderate 71 to 77 degrees Fahrenheit and Severe 32 to 47 degrees Fahrenheit.  The techniques used to re-warm the animal depend on the severity of hypothermia.

 

In the case of mild hypothermia, the rabbit can be treated by packing him between warm water bottles wrapped in towels until his body returns to a normal range.  Care need to be taken to avoid warming the animal two quickly as it can cause the animal to go into a state of shock.

 

If the animal is severely hypothermic, the breathing and heart rate may be so slow that it is hard or impossible to detect.  In such cases the first assumption should always be that the animal is still alive and to begin treatment immediately.  In human medical terms, a hypothermic patient is not considered dead until the patient is warm dead.  A hypothermic animal may appear dead and beyond help because of skin and membrane colors and depressed vital signs.  Always error on the side of life. 

 

Begin treatment by bring the animal into a heated room and allow it to begin re-warming naturally.  The animal can be packed between warm water bottles wrapped in towels.  Avoid rubbing the animal as this can increase the flow of cold blood into the core of the body increasing the depth of hypothermia which can cause re-warming shock.  Continue warming the animal until a normal rectal temperature is reached.  Avoid any direct application of un-insulated hot water bottles to the body of the animal.  The goal is to keep the animal warm, to avoid further exposure to cold and to obtain veterinary care as soon as possible.

 

 

The Story of Smokey 

As a brief testimonial concerning the power of life and the will to survive, I thought this might be an appropriate time to relate the story of Smokey.   Smokey was a little Dachshund with the heart of a German Shepard.  At the time of this incident in 1966, we were living on the Cheyenne Indian reservation where I was a teacher for the Neighborhood Youth Core and Smokey was our first puppy.  I was visiting with a co-worker in our living room in the log cabin we called home.  Smokey, like always was busy playing under my desk when suddenly my desk lamp began to blink off and on and I heard a strange yelping sound coming from the spot where Smoky had just been playing.  A quick check reviled that Smokey had the lamp cord clamp tight in his mouth and was lying on his back with his legs jerking wildly in the air.  I could see tiny sparks of electricity jumping from the break in the cords insulation into the area of his mouth were his teeth were making contact with the bare copper wire.  I immediately grabbed the lamp cord and pulled the plug free from the wall outlet.  With the source of electricity now disconnected Smokey’s little body relaxed and lay still, and lifeless.  As a government teacher, I had been required to complete extensive training in emergency first aid and resuscitation.  Without really thinking I pulled Smokey’s body from beneath the desk and checked for a heart beat; there was none, nor was there any sign of breathing.  My wife grabbed a news paper and we laid Smokey’s body where the discharge from his relaxed bowels would not stain the carpet.

 

 Though Smokey’s tiny body had little in comparison to that of a human body, the concept of resuscitation was still similar and I immediately began CPR.  Pressing gently on his chest I tried to stimulate his heart to begin beating again.  At the end of every two pushes on his chest, I would gently blow air through his nose into his lungs, being careful that my puffs of air were small and not enough to bust his tiny lungs.  I sensed that my co-worker was looking on in disbelief that I was attempting to save the life of a dog that was clearly, by all visual clues, dead.  Without let up, I continued with the CPR.  Smokey’s eye’s were open and unblinking with no appearance of life showing.  Then when all seemed very hopeless, I felt a small movement under my hands, it was a voluntary breath.  I stopped CPR and bent over to listen to his chest, there, where before there had been nothing, I could now hear a faint but steady heart beat.  Smokey’s eye’s flickered, shut then opened again.  His legs began to move and his breathing deepened.  Life was reawakening were just moments before death had seemed victorious.  Smokey rolled over into a more natural position and raised his head.  He was still weak and shaky.  We moved him from the floor, laid him on a warm towel, and did what we could to warm his body and make him as comfortable as possible.  In a few minutes, he was attempting to stand and to the amazement and disbelief of my co-worker, was walking across the floor to his water dish.  Smokey made a full recovery from his accidental electrocution and except for some minor changes in his behavior, came back to us the same dog he had always been.  Smokey went on to live for several years before age and infirmities took their final toll.

 

The lesson learned that day is that life, even when undetectable, can still be reawakened if emergency treatment and care is provided soon enough and with sufficient persistence.  Had it not been for my recent training in first aid I would most likely have, as my co-worker did, considered the accident fatal.  I have always been glad that I gave life a chance.

 

John W. Jones

Copyright March 2006 All rights reserved

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