320 PRINCIPLES OP VETERINARY SCIENCE 



or diarrhea, abdominal or muscular pains, jaundice, anemia, 

 cough, and abscess formation. 



The diagnosis of parasitic diseases depends largely on the 

 finding and determination of the parasites or their eggs. A 

 postmortem examination is often necessary before a diagnosis 

 can be made. The collection of parasites from the stomach and 

 bowels of animals to identify them is best done by placing the 

 contents in a jar of water and stirring it vigorously. After allow- 

 ing the mixture to settle to permit the worms to collect at the 

 bottom, the fluid is decanted off, more water is added, and the 

 process repeated. Finally all the water is poured off and normal 

 salt solution is added. This mixture is then poured into a shal- 

 low dish where the worms are easily seen. 



The prevention of parasitic diseases is largely a matter of 

 maintaining stock in a sanitary manner. Plenty of good feed is 

 more important than anything else, for animals in good condition 

 are less likely to respond to attacks by parasites than those in 

 poor condition. By keeping the skin and hair coat of animals 

 reasonably clean, external parasites can be prevented from gaining 

 a foothold. Many internal parasites enter the body as larvae 

 with the food and drink which should be carefully guarded 

 against contamination with their eggs and grubs. The following 

 salt mixture has been found very helpful in keeping sheep and 

 cattle free from stomach and intestinal worms: common salt 

 280 parts, dried iron sulphate 16 parts, powdered charcoal 12 

 parts, and flowers of sulphur 8 parts. These ingredients are 

 ground or well mixed together and kept in covered boxes within 

 ready access at all times. Eastern sheepmen try to secure new 

 stock from western ranges every third or fourth year as western 

 sheep seldom harbor the parasites which are prevalent in the 

 East for the reason that the ranges are so dry that the parasitic 

 eggs cannot live. When these methods of prevention fail it will 

 be found best to dispose of the particular species of animals that 

 is affected and not restock for a year. In this way all eggs in the 

 soil will be destroyed and the farm made safe. Never allow the 

 stock to range over the entire farm as it would then be impossible 

 to rotate the pastures as may be necessary in certain cases. Fur- 

 thermore, pastures should not be top-dressed with stable manure 

 when they are to be used for grazing animals the following sea- 

 son. The long-continued pasturing of one class of animals upon 



Digitized by Microsoft® 



