122 ANNUAL EEPOETS OF DEPAETMENT OF AGEICULTUEE. 



ing the number and identity of the diseases of fowls embraced in the 

 group commonly designated as common colds, catarrh, roup, diph- 

 theria, and chicken pox. The plan of the work included particularly 

 measures aimed at the differentiation of avian diphtheria from 

 chicken pox; immunity tests for differentiation of diseases; tests of 

 methods of transmission; tests of infectivity of diseases to various 

 species, and possible application of the complement-fixation method 

 and the microscopic examination of tissues. Considerable data on 

 the use of a vaccine for curative and preventive use in chicken pox 

 have been collected. 



_ As outbreaks of other poultry diseases came to notice under condi- 

 tions favorable for research, observations were made upon them. 

 Opportunity has been afforded for work upon coccicliosis and entero- 

 hepatitis. An outbreak of bacillary white diarrhea was studied with 

 particular reference to the agglutination method of diagnosis. The 

 conditions surrounding an extensive mortality of ducks were studied, 

 as well as the pathology and bacteriology of the affection. 



The diagnosis of material sent in by poultrymen has included 

 cases of roup, bacillary white diarrhea, entero-hepatitis, chicken pox, 

 coccidiosis, and fowl cholera. 



PHYSIOLOGICAL INVESTIGATIONS. 



The work on immature veal was brought to a close and the experi- 

 mental data prepared for publication. The study of the com.parative 

 chemical composition of mature beef and immature veal disclosed no 

 differences that were physiologically significant. In a large number 

 of artificial digestion experiments the veal was digested as rapidly 

 as beef. Feeding experiments on cats gave no indication of harmful- 

 ness of immature veal. 



A number of experiments were made on internal disinfection. 

 Cows were fed urotropin by mouth, hydrochloric acid was injected in- 

 travenously, and the milk was then tested for formaldehyde. Definite 

 results have not yet been obtained. 



CONTROL OF BIOLOGICAL PRODUCTS. 



The control of the preparation of biological products, with the ex- 

 ception of anti-hog-cholera serum, hog-cholera virus, mallein, and 

 tuberculin, has been continued under the supervision of the Patho- 

 logical Division. Samples of immune sera, vaccines, and bacterins 

 were procured from time to time in the open market and subjected to 

 bacteriological and potency tests. In several instances the product 

 failed to meet the legal requirements and the manufacturers were 

 notified of the deficiency. It is gratifying, however, that the exami- 

 nation of biological products only very exceptionally proved them 

 worthless or contaminated, and it is apparent that the manufacturers 

 are endeavoring to meet the requirements of the department by pro- 

 ducing pure and efficient products. Further work on this subject is 

 reported under the heading of the Biochemic Division. 



TOXICITY OF DISINFECTANTS. 



The testing of various disinfectants offered for sale to the public 

 has been continued in conjunction with the insecticide and fungicide 

 board. A number of autopsies were held, and in some instances his- 

 tological sectioning of affected tissues has been necessary. 



