205 



ary article, but for its medicinal influence. In addition they should 

 have pure, fresh water once or twice a day. Wlien the animals have 

 become sick good diet should be supplied. As intimated by Mr. Powers, 

 those animals which seem most in need of food take the least, and if 

 they do eat it rasiy even be of harm to them. However desirable it may 

 be to feed animals well as a hygienic measure, still no amount of feed- 

 ing will keep them from being infected when a season favorable to 

 the parasite appears. There must therefore be a continual diligence 

 exercised in keeping the pastures in good condition and the young 

 sheep especially from becoming infected. As the parasites seem to thri ve 

 best in water, it follows that dry pastures should be preferred. The 

 danger of infection from pastures should be diminished by limiting the 

 number of sheep, so that they will not have to eat the grass close to 

 the roots, and by a judicious distribution of the young sheep on practi- 

 cally virgin pastures. Should a pasture have become permanently in- 

 fected from long use it should be plowed up and either cultivated a 

 year or two or allowed to stand idle or surrendered to other stock. 

 The effect of the cold upon the embryos of these parasites is not yet 

 known, and it may be that the alternate freezing and thawing which 

 they sustain is in the Northern States the cause of the destruction of 

 large numbers of them. Leuckart's experiment of keeping the worms 

 in moist earth, during which time many molted and died, indicate 

 that a pasture would be much safer when thoroughly dried after a pro- 

 longed rain than before, and also that such a wet time would be more 

 dangerous for the sheep. A judicious selection of pasturage through- 

 out the year, together with a shifting of the sheep from pasture to past- 

 ure as the season and ages of the sheep seem to require, is the best 

 that can be counseled at present. 



Medicinal treatment may be productive of much good, but is usually 

 resorted to so late that its best effects are lost. Medicines have been 

 administered with the food by drenching, by fumigations, and by 

 tracheal injections. Salt and copperas in proportions of from 1 of cop- 

 peras to 25 of salt, and of 1 of copperas to 4 of salt, the last mixture 

 being given in wet weather, has been advised {The American Me- 

 rino^ by Powers, 1887, p. 285). The weaker mixtures maybe kept con- 

 stantly before the lambs for eighteen months. The stronger should be 

 alternated every two or three weeks with clear salt. Powers kept it 

 constantly before the lambs until after the second summer. I would 

 deprecate the use of copperas for any continued length of time, for it 

 ufot only harms the teeth, but if persisted in loses its force as a tonic 

 remedy. In administering dry medicines in food much of their force is 

 lost, for they are very apt to accumulate in the paunch or first stomach. 

 Medicines given by drenching are more expensive in the dosing but 

 more effective, for small quantities of fluids pass directly into the mani- 

 folds or third stomach, and thence into the fourth stomach, especially 

 if the sheep be thirsty. But few of the many remedies advised are in 



