Sore hocks in rabbits is also known as bumblefoot or ulcerative pododermatitis. This is a bacterial infection of the skin. The part it effects is when your bunny is sitting, the part of their back feet which are touching the ground (called their hock's).
If you leave this untreated it can deteriorate to become a disease on the skin in which emits pus which is also known as pyoderma.
This is an inflammation of the balls of the feet and is usually caused by infection. This infection occurs when you pet ha broken skin on the bottom of their feet and bacteria gets into it. This is a wound or abrasion on the foot.The skin can become broken from the bottom of the cage floor if it is just wire mesh.
Their are different grades of this depending on how bad it is:
Grade I - This is a milder form of the disease and they could have fur loss, and some other early symptoms on their back feet
Grade II - At this stage they will have fur loss on their feet and possible have swelling and redness on the feet and hock's.
Grade III - At this stage they will experience broken skin, with possibly a scab which could potentially be an opportunity for an infection
Grade IV - By this stage the rabbit is highly likely to have an abscess, and inflammation of the tendons or deeper tissues within the hind limbs of their body
Grade V - The rabbit at this stage is likely to experience severe symptoms of the sore hocks in rabbits, including bone marrow infection, swelling of the joint tissue and possibly inflammation of the tendons which is known as tendonitis. From this they may walk abnormally or have an abnormal stance or posture.
This will usually first appear as a small, reddish bump/lump on the bottom of the foot. This may look similar to calluses on human feet. Their is a closed abscess inside the lump. When the lumps grow large, they may break open and bleed. This is when they could be infected.
There isn't a certain treatment for this so you may have to visit a vet to see what would be the best for your bunny. To help prevent bumblefoot in rabbits, you need to make sure that there is no trauma to feet which could be from walking on wire mesh, a clean hutch so they can't get an infection and solid surface floors.
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