Experimental cholecyst-lobectomy was tried in 10 dogs. The right medial and the quadrate lo bes which lie close to each other enclosing the gall bladder were excised. All operations were performed without prior preparation of the liver tissue or vessels. It was effected merely by ligatins the pedicle of the lobes. The animal withstood the operation well and showed no serious post-operative effects. Blo od cytology (R.B.Cs., W.B.Cs., total count pe rmm differential leucocytic count percent Hb concentration and blood sedementation rate ) were investigated before and after operation for 45 days.