President McCleave: At the luncheon to which you are all invited, as you know, I think most of you have signed up the cards, you will be at the Bellevue Hotel the guests of the San Francisco Commission. (Dr. McCleave then gave directions as to how to reach the Bellevue Hotel.) Our program for this conference is unique in that I think with one exception, every man who is down on the program for a paper is present to read it. Now that is due to the fact that in inviting a good many of our membership to present papers at this meeting I impressed upon them that I did not want them to give me a paper unless they were going to be here. As I say, I think that is unique. I have never attended a medical meeting where the men down for papers were present in the percentage that they are here practically almost one hundred per cent. It is due to the men who are giving us these papers that we be prompt in our attendance at the meetings; it is a courtesy that is the least that we can pay them. I will ask you to be here promptly at two o'clock for the afternoon's session. Do not run around after luncheon, but come right back here and be on hand at two o'clock promptly so that we may open our meetings promptly that we may be able to get through with this afternoon's program. I will make another announcement that is not on the program that is printed; and that is, that after the meeting this afternoon we will have some automobiles here for you eastern people who are perhaps making your first visit here. We want to take you through our Park on the beach overlooking the Golden Gate, a very beautiful drive; and we will leave you at the Exposition grounds by half past five or six. You can run in and see this Milk Show, those of you who will; and then I would advise you to stay on the grounds and have your dinner and enjoy the evening there, because I presume most of you will be interested to do that. It is not feasible for the Commissions to arrange a dinner for you tonight at the grounds; but such as like to can make up little parties and you will find a number of good dining places. The Old Faithful Inn is a nice place to have a dinner and you will be right on the zone where you can enjoy yourselves in any way that you desire. Please be here promptly at two o'clock. The Convention now took recess until two o'clock P. M. SECOND SESSION Thursday Afternoon, June 17, 1915 The Convention met pursuant to recess, President McCleave in the Chair. President McCleave: The first paper this afternoon will be by Chester H. Roadhouse, D. V. M., Veterinarian of the San Francisco and Alameda County Commissions, on the subject, "Methods of Control in Certified Dairies Supplying the San Francisco Bay Region." Dr. Roadhouse delivered his paper, as follows: Methods of Control of Certified Dairies in By C. L. Roadhouse, D. V. M., University of California, Berkeley On account of the standard regulations of the American Association of Medical Milk Commissions, the supervision of Certified Dairies in the San Francisco Bay Region is, no doubt, in the main uniform with most other sections. However, there are certain differences practiced here in the carrying out of these regulations, which, (we believe would be of interest at this time,) with the results obtained in the supervision of six Certified Dairies together. The expert work for the Alameda County and San Francisco County Medical Milk Commissions is carried out by the Veterinary Division of the University of California with the following procedure: 1. Semiannual tuberculin tests of all Certified Dairies. 2. The tuberculin testing of all purchased animals. 3. Monthly veterinary inspections of dairies. 4. Monthly sanitary inspections of dairies. 5. Weekly inspections of distributing stations and wagons. 6. Semimonthly bacterial examinations of milk. 7. Semimonthly chemical examinations of milk. (The chemical analyses are made by the nutrition division of the University). Health of Herd: Having in mind the health of the herd as a first consideration, we can report satisfactory results in controlling tuberculosis by the use of the tuberculin tests. The first Certified Dairy in the San Francisco Bay Region was established in 1905, a second dairy became certified in 1908, and a third in 1909. The demand for Certified Milk made it necessary for the owners to purchase large numbers of animals and they purchased any animal that passed the tuberculin test. In some cases thirty per cent. of the animals tested did not pass the test, but those that did pass were added to the Certified herd. When the next and succeeding semiannual tests were made many of these purchased animals reacted and had to be removed from the dairies. In a very few cases animals that passed the semiannual test showed physical signs of tuberculosis and had to be removed from the herd. It was evident from the results of the work at this time that animals which had been kept in badly infected herds could not be depended upon to pass future tuberculin tests. In order to improve this condition the Commissions in 1909, adopted the ten per cent. rule which provided that, if ten per cent. of the animals to be purchased from one source reacted, none could be accepted. This rule has been continued and, although it has been a hardship to the dairy owners on account of the difficulty in finding animals that would pass the test under this requirement, still there is little doubt but that it has been the main reason for the gradual decrease each year in the percentage of reactors. During the past year 2,246 tests were made in the six Certified Dairies; 86 animals reacted; 74 per cent. of these reactors were from animals purchased within the last three years, which shows that even with the stringent ten per cent. rule it is difficult to keep out tuberculosis where animals are being continually purchased. Method of Testing: Following the development of the intradermal tuberculin test and its use in California by Haring & Bell as published in Bulletin No. 243 of the California Agricultural Experiment Station, the Commissions adopted its use for semiannual tests to be alternated with the subcutaneous test. The following data for each dairy shows the results of the two methods of testing. Results from Subcutaneous and Intradermal Tuberculin Tests in Certified Dairies A summary of the foregoing above is given in the following table: Animals Tested During First Half of 1914 by Subcutaneous Method No. animals tested... Percentage reacting.. 1,011 35 3.4 Animals Tested During Second Half of 1914 by Intradermal Method Animals Tested During First Half of 1915 by Subcutaneous Method A comparison of results in the foregoing table shows that 3.4% of the animals reacted to the subcutaneous test of 1914. The intradermal test which followed later in the year showed 5% of the animals reacting, an increase of 1.6%. The subcutaneous test made this year, following the intradermal, showed 2.2% reacting, which is 2.8% less than to the intradermal. It is reported by Haring and others that the intradermal tuberculin test is somewhat more searching in its diagnosis of tuberculosis in animals than the subcutaneous method and that it may show a reaction in animals with inactive lesions, that in some cases might escape the subcutaneous test. This same result would seem to have followed the use of the two tests in Certified Dairies in this region. The intradermal tests no doubt weeded out animals with inactive lesions and can be credited for the considerable reduction in the number of reactors at the last subcutaneous test. In all cases purchased animals are tested by the subcutaneous method. Where the responsibility for the health of the animals in Certified Dairies rests upon one individual it is believed that better results are obtained in maintaining healthy herds. It is on this account that the Commissions insist upon the testing of purchased animals, as well as all other tests, being made by the Official Veterinarian and it is believed that this is essential to the well being of the herds and to the keeping of uniform records. Monthly Veterinary Inspections: The veterinary inspections cover the items specified in the Regulations of this Association. The point of greatest interest in connection with these inspections is the conditions for which animals are removed from the herd. Our reports show that of the 10,238 animals observed at the various inspections during the year 129 or 1.1% of them were affected with udder trouble. Although we have no data, showing the percentage of udder troubles in other dairies where the udders of the animals are not washed, we believe that there is at least as much trouble of this kind in ordinary dairies and that regularly washing the udders of cows does not increase udder trouble. In the Certified Dairies animals with udder trouble are seldom found in the milking stable. The dairy owners can easily recognize most cases of udder trouble so that we have taken the position that it is the duty of the man in |