12. Unless he has just and reasonable grounds, a veterinary surgeon may not cease to act on behalf of a client. The following in particular constitute just and reasonable grounds:
(1) loss of the client’s trust;
(2) the fact that the veterinary surgeon is in a situation of conflict of interest or in a situation such that his professional independence could be questioned;
(3) inducement by the client to perform illegal, unfair or fraudulent acts;
(4) being misled by the client or the client’s failure to cooperate;
(5) the client refusing to pay the veterinary surgeon’s fees; and
(6) being unable to communicate with the client or to obtain from him the elements considered necessary to continue providing professional services.