101 



or boxes bnt little expense would be necessary to guide it into troughs. 

 These troughs should be kept clean. The lambs should not be allowed 

 to drink elsewhere, nor to eat grass in moist places unless It is abso- 

 lutely certain that these places are uninfected. The location of corrals 

 so that they either surround water or that the drainage is from them to 

 the water seems to be a most harmful practice. It not only makes the 

 water fouler but renders it more likely to hold parasites. Herders 

 should be instructed neither to feed nor water at the prairie pools. If 

 there are places where it is advisable to water they should be prepared 

 like the watering places at the corrals. The nearer the ranchman can 

 arrive at giving the lambs pure fresh water the less infected with para- 

 sites will they become. The salt for the lambs and young sheep should 

 be fed from boxes placed near water places and kept constantly full. 

 They will take no more than they want and will be all the healthier if 

 they have all they need. If they are deprived for a time they may at 

 first salting eat more than is good for them. A little eaten daily is 

 physiologically better than the larger quantity eaten at intervals. The 

 object of feeding the salt at watering places and from boxes is to keep 

 them from licking the dirt where salt has stood and to keep them from 

 eating the prairie alkali. In addition to the opportunities afforded them 

 of being infected with parasites "from the salted ground there is the in- 

 jurious effect of the swallowed sand. This sand often packs away in 

 the gall ducts and produces disease. 



It may be when the gap in the life history of Twnia fimhriata is 

 known that a single measure of i^revention will eradicate it from the 

 Hocks. Until then the general measures prescribed above are to be 

 recommended. 



There are various minor precautionary measures to be fulfilled that 

 will help affected sheep to live through the colder winter, and finally 

 to render effective service in spite of the parasite. The post mortem 

 examinations have led me to expect that from 80 to 95 per cent, of each 

 flock is infected. JS"ow, were all of these to suffer as some of the more 

 diseased do, sheep-ranching would be at its end. Fortunately a sheep 

 may have a few parasites and not be seriously affected by them. This 

 is shown by the fine, large sheep slaughtered which are passably fat and 

 yet contain twnke. It is a frequent remark of the ranchman that if 

 he could carry his lambs and yearlings through they would do well 

 enough afterwards. It is these younger and growing animals'that suc- 

 cumb soonest to the parasite. It is a rule that all young and growing 

 animals are more seriously disturbed by the i^resence of parasites than 

 older ones. Young lambs born in May or June have necessarily but a 

 short time in which to grow before the cold season. When food is 

 plenty, and there is no disturbance of their digestion, or other ailments, 

 they enter winter strong enough to endure the weather without partic- 

 ular suffering. Interference with digestion, lack of food, or any ail- 

 ments render the lambs so much the weaker, and consequently less able 



