116 ANNUAL REPORTS OF DEPARTMENT OF AGRICULTURE. 



FORAGE POISONING. 



No further evidence has been obtained that Bacillus hotulinus is a 

 factor in forage poisoning of animals, but reports from other sources 

 indicate that this organism has been responsible for the deaths of 

 horses and sheep. It is a fact of long-standing knowledge that it is 

 possible to produce an antiserum against disease caused by B. hotu- 

 linus, and several animals have been treated with the idea of pro- 

 ducing a serum for experimental purposes in spontaneous outbreaks 

 of forage poisoning, but it has not been found feasible as yet to follow 

 up this line of research in order to demonstrate definitely its worth. 



RABIES 



The number of cases examined for rabies was somewhat less than 

 during the preceding year. One hundred and fourteen suspected 

 cases were received and submitted to laboratory examination. Of 

 this number 45 were positive, 65 negative, and in 4 cases no diagnosis 

 could be made, as the material had undergone advanced decomposition. 

 The cases included 93 dogs, 6 cats, 10 cattle, 4 hogs, and 1 sheep. 

 Thirty-four of the cases were from the District of Columbia, 18 from 

 Maryland, 51 from Virginia, 4 from West Virginia, and 7 from other 

 States. In every instance where a person had been bitten, animal 

 inoculation was made when the microscopic findings were negative. 



BLACKLEG VACCINE. 



The demand for vaccine for immunizing cattle against blackleg 

 has continued, and enlarged facilities have enabled the division to 

 meet all demands promptly. During the j^ear 4,204,975 doses were 

 distributed to stock owners free of charge. 



With the object of producing an immunizing agent against black- 

 leg which would possess a higher degree of potency than the atten- 

 uated virus vaccine that is in common use at the present time (Kitt's 

 method and modifications), experiments were undertaken to produce 

 a germ-free toxic culture filtrate and to determine its relative potency. 

 After many attempts a process was devised for preparing such a 

 product possessing highly satisfactory immunizing properties and for 

 concentrating the vaccine in paste form so as to make it relatively 

 stable. Necessary dilutions are made with water at the time of 

 inoculation into the animal to be immunized. 



ANTIANTHRAX SERUM. 



Serum from horses that are immune to anthrax has been prepared 

 for the treatment of that disease, both in man and in animals, and 

 many requests for it have been filled, notably in emergency cases in 

 which anthrax has been diagnosed in human patients, and where 

 serious outbreaks were causing heavy losses of live stock. 



POULTRY INVESTIGAT ONS. 



A large number of experiments were carried out with various drugs 

 and antiseptics used in the treatment of disease for the purpose of 

 establishing in each case the toxic dose for fowls. Through the 

 knowledge thus gained it is possible to fix the most effective medicinal 

 dosage. Little information on this subject apj)ears in the literature 

 on poultry diseases. 



