216 DEPAETMENTAL REPORTS. 



CONTROL OF CONTAGIOUS DISEASES. 



Southern cattle inspection. — During- tlie quarantine season of 1899 

 the employees of this Department supervised the movement of 

 1,058,484 cattle, in 39,976 cars, from the district infested with the 

 Southern cattle tick {Boophilus hovis); 39,663 cars were cleaned and 

 disinfected. 



In Texas 357,422 cattle were inspected and identified by brands as 

 originating- north or west of the quarantine line, and were permitted to 

 be sliipped by rail or trailed to other States or Territories for grazing. 



In conjunction with the authorities of the State of Missouri 6,065 

 cattle originating in the northern counties of Arkansas were inspected 

 and permitted to be driven into the former State. 



The prevention of sheep scab. — The sheep industry of the United 

 States has long suffered severely from the form of scabies produced 

 by the Psoroptes communis, and commonly known as sheep scab. 

 Many of the Western States and Territories have been badly infected, 

 and the sheep shipped from these have spread the contagion to the 

 feeding- yards, stock yards, stock cars, and to all the ramifications of 

 the channels of interstate commerce. As a result of this dissemina- 

 tion of the contagion, the Eastern feeders who have purchased store 

 sheep have very often found them infected with this troublesome dis- 

 ease. There have consequently been severe losses from the disease 

 in all parts of the country. 



It has been a difficult matter to get control of the sheep traffic in 

 such a manner as to prevent the spread of scab, without at the same 

 time too seriously interfering with the marketing of the animals. To 

 lessen the burden of the sheep owners as much as possible, the regu- 

 lations were at first very simple and easily complied with ; they have 

 been made more stringent and effectual as the nature and objects of 

 the requirements became known. 



The first step in the process of control was to give notice of the 

 existence of the disease, and of the provisions of the law prohibiting 

 the shipment of diseased or exposed animals from one State or Terri- 

 tory to another. At the same time a bulletin giving information of 

 the nature of the disease and the methods for curing it was widely 

 distributed through the affected sections. Diseased sheep coming 

 into the stock yards were required to be dipped before being shipped 

 to other States or sold as feeders. 



As the results of the dipping were not satisfactory, this operation 

 was put under tlie supervision of Bureau inspectors, and the dipping 

 liquid was required to be made of certain specified ingredients used 

 in proper proportions. Inspectors were also placed at all points where 

 railroads crossed the Missouri River, in order to discover the diseased 

 sheep and stop them before they gained access to the large stock yards 

 of more eastern points. Finally, inspectors were distributed through- 

 out the States where the traffic originates to Inspect the sheep and 

 certify to the healthy ones at the time of shipment. 



The effect of this work has been very marked. Sheep owners have 

 been encouraged and stimulated to treat their diseased animals and 

 free their ranges from the contagion. There is a much smaller num- 

 ber of diseased sheep found in the stock yards, and the infection is 

 gradually disappearing. A few years more of earnest work will be 

 sufficient to eradicate this disease and to remove in this manner one 

 of the greatest sources of loss to the sheep industry. 



Experiments with reference to tliis disease are in progress at the 



