I have an 8 year old St Bernard who has always been in good health. That was until saturday, when he tried to get up on saturday evening his back end collapsed underneath him leaving him winded, we managed to get him up and moving and he seemed ok. Then we walked him on Tuesday morning and it happened again, so patiently got him home afew steps at a time as he was pretty unsteady on his feet. Hes also not eating much but drinking loads. Took him to the vets and he is now having blood tests done. Only just got home from work to a flooded kitchen, with pee and a doderey looking dog. Any ideas what it could be??????