We have seen a couple of cases recently affected by suspected Hypervitaminosis A. This has been the result of the owners feeding liver regularly (e.g. daily). Liver as a food source should really only be fed as a treat once a week or so. If fed on a daily basis it can cause lameness, ataxia, reluctance to move and paralysis. Bony changes are seen on the spine when x-rayed. Symptoms can settle down once feeding is discontinued but some permanent changes to the skeleton will often remain.
Please note daily feeding of dried liver treats does not cause this problem.