DISEASES OF SHEEP 589 



drinking water and a plentiful supply of salt, should be observed 

 in this disease as for other parasites. Judicious fall and winter 

 marketing of infected sheep will also tend to lessen the chances of 

 infection. If pastures are known to be permanently infected, then 

 they should be turned over to other stock for a year or two before 

 being again grazed on by sheep. When it is practical, on the 

 smaller farms, the sheep lots should be plowed, and either planted 

 or left fallow. The object of change of pasture and of plowing is 

 nearly the same; in the one case to wait until the parasites have 

 died out; in the other, to bury them beneath several inches of soil, 

 from which the sheep owner may rest assured they will not emerge." 



The conclusions deducible from the results of experiments may 

 be stated as follows : 



(1). That sheep suffering from Nodular Disease of the Intes- 

 tines, when placed upon a hitherto clean pasture, transmit infection 

 to it through extrusion of the nodule- worm (Oespphagostoma Col- 

 umbianum) from their bowels, probably with their droppings. 



(2). That when sound lambs are permitted to occupy a pasture 

 so infected, they will contract nodule disease. 



(3) . That when the surface of an infected pasture is turned un- 

 der by ploughing, and the land cropped, even for a single season, 

 the infection may be destroyed. 



(4). That when sound lambs are allowed to occupy and graze 

 upon a pasture (previously infected) after being cultivated and 

 cropped, as above mentioned, they will remain free from nodule 

 disease. 



(5). That lambs, the progeny of ewes affected with nodule dis- 

 ease of the intestines, can be raised free from this disease, provided 

 proper methods are adopted to prevent contamination, and, 



(6). That, if an infected pasture is placed in cultivation for a 

 time, to destroy the parasites on it; clean lambs raised, as suggested 

 by the method adopted by us, or purchased and known to be clean, 

 and all affected sheep disposed of for slaughter (this ailment being 

 confined to the intestines mainly, and not rendering the flesh unsafe 

 as an article of human food), the disease may eventually be eradi- 

 cated from both the land and the flock. 



(7). See also treatment for Stomach "Worms. 



Strongylus Ventricosus, Rud. This species is found asso- 

 ciated with Strongylus filicollis in the upper part of the small in- 

 testine. It is generally found in the fall of the year. It is very- 

 small and so far as known, of little consequence. 



Strongylus Filicollis, Rud. This is one of the very small 

 worms affecting the intestine of lambs and sheep. Taken by itself 

 it probably does little harm. It may be found in considerable num- 

 bers in the fall. It is so delicate that it would escape observation 

 from the ordinary observer. 



Dochmius Cernuus, Creplin. This is a rather stout parasite 

 of the small intestine and may be mistaken for the twisted stomach 

 worm by those not accustomed to examining for parasites. It is 

 fairly stout and is found attached to the mucous wall, as it feeds 



