AMERICAN VETERINARY MEDICAL ASSOCIATION. 125 



ties of controlling it in range cattle were outlined. Cattle may easily 

 become reinfected after the mange mites have been destroyed by (lip- 

 ping. Compulsory dipping before shipment is considered an unneces- 

 sary hardship for the cattlemen of Colorado. 



N. S. Ma} r o discussed the same problem as it occurs in Kansas. He 

 considered quarantine and dipping as absolutely necessary. The cage 

 and the swimming-vat methods have been employed. The swim- 

 ming vats should be from 40 to 60 feet long. The most effective, 

 cheapest, and least injurious dip is the homemade lime-and-sulphur 

 dip. Coal-tar dips are considered objectionable on account of their 

 odor, the variation in strength, the irritation which they cause to the 

 skin, and their excessive cost. Most of them cost from two to three 

 times as much as the lime-and-sulphur dip. It was recommended that 

 the dip be made so as to show a slight excess of sulphur. Cattle 

 should be dipped twice, ten days apart, in the spring, with the dip at 

 a temperature of 110° F. Cotton-seed oil was found to be effective as 

 a dip, but was rather too expensive. Hand treatment, in the speaker's 

 opinion, was of little value. Well-fed cattle frequently become 

 affected. Apparent recovery is always followed by a recurrence of 

 the scab, and infection is hard to detect during the summer months. 

 Proprietary medicines are considered a nuisance in connection with 

 this disease. 



In discussing this paper, J. G. Rutherford also stated that fat cattle 

 could become infected. In northwest Canada it is impossible to dip 

 cattle in the spring. The Canadian regulations require that veterinary 

 officials collect and dip stray cattle or cattle of owners who, for any 

 reason, fail to dip. The lime-and-sulphur dip was considered the most 

 effective, but hand treatment also gave good results under certain 

 circumstances. 



M. E. Knowles stated that hand treatment with dynamo oil had been 

 successful with him in 4,000 cases. To the djmamo oil about 2 per 

 cent of sulphur is added. The best method, in the speaker's experi- 

 ence, for keeping the dip warm was by the use of a caloric transformer 

 as employed by brewers. The dipping vats in Montana contain from 

 10,000 to 30,000 gallons of water. N. S. Mayo reported that he had 

 had better results with ordinary steam pipes than with the caloric 

 transformer, but preferred a tank furnace, and strongly recommended 

 a dip formula containing 12 pounds of lime and 20 pounds of sulphur. 



A. T. Peters found by extensive correspondence with cattle raisers 

 that a very low percentage of sulphur was used in some homemade 

 dips. A formula has been devised for the preparation of a lime- 

 sulphur dip which may be manufactured by commercial firms so as to 

 have a standard strength. 



A communication was received from A. Liautard on needed reforms 

 in veterinary education in the United States. The author reviewed 



