Friday, April 28, 2017

Self-Injury In Rabbits


Here on the TAP Homestead and Rabbitry, we are a small working farm. The primary goal here is to provide for ourselves as much fresh fruits (blackberries, apples, and pears) vegetables, eggs, and meat (rabbit and chicken) as possible. As well as supplement our income with rabbit and chicken sales. We have taken the Blue Bell approach in that “we eat all we can, and we sell the rest.” Because of this predation, injury or disease that causes us to lose a productive animal is not something that we like to experience. Unfortunately, it happens, and such is the circle of life on the farm.

The purpose of this article is to share with you the rare experience that you may have when you embark on raising rabbits for meat and or sales. We have been raising meat rabbits now for three years, and this was he first time that we have had a rabbit engage in the process of self-injury or mutilation. It is my hope that this article will shed some light on this subject and although rare, if you happen to experience this in your herd, you will know that you are not alone. Included at the end of this article is a picture of the self inflicted injuries that our New Zealand Red (NZR) buck had inflicted upon himself. They are quite graphic, but I felt the need for them to be included so that you could see the extent of what he did to himself in just a few days.


Possible Causes

There are many theories as to why a rabbit begin to chew on their feet, but there is no definitive test that can determine the exact cause of this behavior. For the owner of a 'pet' rabbit, the first step would be to take their animal to the veterinarian to have it examined, and a multitude of tests run. However, for the meat producer or small homesteader, this is most often not a fiscally reasonable option. Spending $100 or more for a breeder that can be easily replaced by another for $30 - $50 is somewhat wasteful, even if the rabbit was of exceptional quality. So what causes a rabbit to engage in self-injury? Self mutilation by rabbits may be caused be any one, or a combination of the following.

According to the Textbook Of Rabbits Medicine, 'The cause of self-mutilation is not clear and it is likely that a number of conditions may result in this type of behavior. Obsessive/compulsive behavior., hypersensitivity, harvest mite infection, atopy and contact dermatitis are among the causes that have been considered. Many rabbits carry Cheyletiella parasitovorax and/or Leporacus gibbus mites and hypersensitivity is a possibility' (Varga p. 240). In addition, the authors indicate that 'self-mutilation sometimes appears to be a psychological disorder. Active, sociable animals seem most susceptible. Environmental enrichment, including the opportunity to exercise and a bonded companion can be successful in preventing the syndrome' (Varga p. 240).

A five year study conducted by scientists regarding the problem of self-mutilation of laboratory rabbits began with the basic assumption that this behavior was caused by poor nutrition, caging, social contact, and or environment and care. The initial outcome of their study indicated that there was no specific trigger for self mutilation. 'No other behavioral abnormalities or signs of disease were evident. Self-mutilation was seen both in stock, breeding and experimental animals, in rabbits kept singly in cages and in those housed in groups on the ground, in rabbits kept in different buildings and under the care of different staff members. This behavioral abnormality of Checkered crosses has also been observed in animals after being placed into other institutions or private homes. No evidence of an agent responsible for the occurrence of self-injury could be found with parasitological, mycological, histological, clinical or haematological examination' (Iglauer, et. al). Their conclusion after completing their five year study was that the cause of the self-mutilation in theses cases was of a psychological not physical condition. Once 'the condition was recognized as an obsessive-compulsive behavioral disorder. Thereafter, animals were hindered from inflicting further self-injury' (Iglauer, et. al).

It would appear that the evidence strongly suggests, that when there is no physical cause, that self-mutilation is rabbits comes as a result of a psychological disorder, but other environmental, age, or stress related factors cannot be totally ruled out. Some of the other factors that have been discussed as possible causes for self-injury or mutilation include:
  • Pain from arthritis (primarily in older rabbits)
  • Nerve damage related to previous injury or injection site
  • Stress and boredom, a rabbit may chew on it's own foot when bored or stressed
  • Contact Dermatitis
  • Presence of a foreign body in the foot or fur
  • Contaminated food supply (rare)
  • Hereditary conditions (psychological disorders)
  • Infestation of the skin by parasites such as fur mites or burrowing mites



Prevention

So how do you keep your rabbits from self-mutilation? The problem is that without being able to identify the exact trigger or cause of the foot chewing or self-injury, it is rather difficult to prevent the problem. Having said that, there are some overall strategies that you can implement to possibly minimize any potential self-mutilation problems in the future. As I mentioned in some of my earlier articles on rabbit nutrition, a diet high in fiber is important to rabbit health, supplying your rabbit(s) with something to chew on other than themselves is important to relieve boredom. 'Chewing through a mound of hay or grazing grass prevents boredom as well as providing indigestible fiber. Toys, such as cardboard boxes or branches of wood will also provide entertainment' (Varga p. 240). If however, the problem of self-mutilation develops as a result of a psychological disorder, there is really no way for you to prevent the problem from occurring.


The Solution

We examined all the possible things that we believed that could have led to this condition in 'LER'. My wife treated his wounds, but he continued to chew on his feet on a daily basis. Our initial observation was that he did not have any pain and this activity did not keep from from eating. In fact, because he exhibited no outward signs of pain or distress, we did not notice this practice until he had be doing it for a few days. Attempting to determine the cause, we examined all the things which we discovered in our research regarding self-injury in rabbits. There has been no change in his diet, environment, and we do not believe that any new stressors were apparent that would have been a factor. It could have been related to arthritic pain, but he was only three years old, and he had no other outward signs of physical injury that we could see upon examination. We could not find any foreign object in either of his back legs or hocks that would have caused him pain. Honestly, we were stumped as to the cause, and whether it was physical or psychological in nature.

Unfortunately, we could not allow him to continue this practice. For us, as breeders of meat rabbits and small time homesteaders, the only viable and humane option was to euthanise our NZR buck LER. It is not something that we wanted to do, or an action that we took lightly. LER had been a really good breeder for us, and fortunately we had a son of his from a prior breeding. In addition, we bred him the morning that we had to put him down with one of our NZR females 'Dottie' so we will keep the best male from this litter as well.


Conclusion

When you live on a working farm, regardless of size, any and all livestock that you have need to be able to perform at their designated function in order for you to make ends meet. Any and every farmer I have known hates to lose livestock to predators or disease, however both are an inevitable part of farming and ranching. While our chickens and rabbits are working animals, there is always a bit of angst when you have to dispatch of an animal that you have become attached too.

Unfortunately, we have no idea what caused our NZR buck LER to start to process of self-injury, but nothing that we did could stop him from hurting himself. When we look back on all the possible causes, I am left to wonder if it was indeed more of a psychological problem than a physical one. Even with his self inflicted injuries, he never displayed any discomfort and was able to breed this morning without any problems. Whether it physical or psychological, at this point is really not up for debate. I simply wanted to share with you our experiences regarding this problem though rare as it is, it sometimes happens. All you can do is to take the necessary precautions to ensure that your rabbits have access to proper nutrition (food and water), a clean home in which to live, and as stress free environment as possible.

Of course all is not lost, as I mentioned, we have a breeding male from a previous litter of LER's that was intended as his replacement, and we were able to breed him this morning to one of our other red doe's, so his genetic line will continue. So ends another day on the farm with both the beginning and end of life. We will miss you LER. I encourage you to do any additional research that you think may be necessary regarding self-injury in rabbits. As always, if you have enjoyed this article or have found it informative, then please share it with your friends. Don't forget to send us a friend request on Facebook or Google+ so that you will not miss any of our latest articles.

Author's Note: By clicking on the link below you can download a free PDF version of the 'Textbook Of Rabbit Medicine'. It may be a bit technical, but the information is quite through and something that every raiser of meat rabbits should have in their library.


References:

Haddon, Celia, Rabbits Which Chew Their Feet or Body, 2007, Accessed April 20, 2017

F. Iglauer, C. Beig, J. Dimigen, S. Gerold, A. Gocht, A. Seeburg, S. Steier and F. Willmann. Hereditary Compulsive Self-Mutilating Behavior In Laboratory Rabbits. Lab Animals, 1995, 29:385-393

Patry, Karen, The Rabbit Raising Problem Solver, Storey Publishing, North Adams, MA, 2014.

Van Pragg, Ester PhD., Self-Mutilating Behavior In Rabbis, MediRabbit.com, Accessed April 23, 2017.


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