442 MANUAL OF FARM ANIMALS 



dead, and the animal takes on a starved appearance. Scour- 

 ing is more or less frequent. The best evidence, however, that 

 the lamb is afflicted with stomach-worms is the presence of the 

 small worms in the droppings. Older sheep also become affected, 

 but seem to withstand the ravages of the worms better than 

 lambs, due no doubt, in the lambs, to the more tender condition 

 of the stomach wall and to the milk diet. 



The life history of these small worms seems to be simple and to 

 furnish a clew to the means of prevention in lambs. The worms 

 become mature in the body of the older sheep and, laden with 

 eggs about to hatch, pass out with the excreta. Just what the 

 worms do outside the sheep's body is not known. When it is 

 moist and warm, in some way the worms find their way into the 

 lamb's stomach. Perhaps the small worm is taken in while 

 eating, perhaps by drinking surface water. We know that 

 warmth and moisture are necessary for the transfer, hence 

 there is little danger in the North, on mountain uplands, and but 

 little danger in the dry regions of the West. The method of 

 prevention is to remove the lambs and place them on fresh or 

 preferably sown pastures before there is danger of infection. 

 Lambs receiving no other food than grass and the dam's milk are 

 much more likely to be attacked than those fed grain in addition, 

 particularly if the grain contains linseed-oil meal. The only 

 safe way, however, is to remove the lambs to new pastures before 

 infection. 



In case lambs become infected, treatment should be resorted 

 to, though many practical sheep owners state that the treatment 

 at best is not satisfactory. Circular No. 35, the United States 

 Department of Agriculture, Bureau of Animal Industry, reports 

 that satisfactory results were obtained from the use of coal-tar, 

 creosote, thymol, and gasolene. The following is taken from 

 the circular, as it gives a general idea of the treatment for other 

 worms as well: — 



Coal-tar Creosote. — Excellent success in treating sheep, 



