DISEASES OF SHEEP 587 



INTESTINAL WORMS. 



NODULE-DISEASE OF THE INTESTINES OF SHEEP (OESOPHAGOSTOMA 

 COLUMBIANUM, CUR.). 



There is hardly a State in the Union that can claim freedom 

 from this disease among its flocks. For some time it had been mis- 

 taken for tuberculosis, the nodules, or tumors, on the intestines re- 

 sembling, somewhat, the tubercles of consumption ; but later inves- 

 tigation revealed the presence of a very minute round worm as the 

 true cause. 



The disease gets its name from the nodulated condition of the 

 intestines, they being, in advanced cases, thickly studded with nod- 

 ular enlargements all along their course, as far back as the last por- 

 tion of the bowel (rectum). Everyone who has butchered sheep, 

 in many sections of the country, must be familiar with the appear- 

 ance, although, perhaps, ignorant of the cause of this condition, 

 known popularly, in some localities, by the term, knotty-guts. 



In the adult stage, the worm, or parasite (Oesophagostoma Col- 

 umbianum) is about one-half an inch in length, and may be found 

 located in the intestines, and more particularly, the large bowel. 

 The immature stages or forms, vary in length from 1-100 to 1-6 of 

 an inch, depending upon age and stage of development. These are 

 found encysted in the nodules. The writer has dissected quite a 

 number of the larger, older, tumors, without finding the parasite in 

 them, and from which we would infer that they had escaped into 

 the intestine. The life-history of this minute worm, so far as ap- 

 pears to be known, from the more recent investigations, is as fol- 

 lows : The mature female lays her eggs in the intestine. The eggs 

 hatch in a short time, and the embryos, or minute immature worms, 

 pass, in some manner, through the mucous, or internal, lining of 

 the bowel, and become encysted or embedded there; and the irrita- 

 tion produced by the worm seems to give rise to the nodules or tu- 

 mors, which can be seen, of various sizes, projecting from the intes- 

 tine, sometimes along its entire course. 



The tumor consists of a cheesy material, often greenish in color, 

 which, on breaking its outer covering, can be squeezed out. It is 

 thought by Dr. Curtice that the embryos are the chief cause of the 

 trouble, and that the adult worms produce but very little, as the 

 latter are comparatively few as compared with the number of tu- 

 mors. Some of the adult parasites, and probably some of the eggs, 

 pass out from the intestines with the manure, and in this way pas- 

 tures and other feeding quarters are infected; and in turn, shallow 

 and sluggish watering places into which they drain. There is how- 

 ever, a stage in the life cycle of the worm that seems to be still un- 

 determined. That is, from the time it leaves the bowels with the 

 manure until it is again found in the tumors on the intestines. 



The symptoms of nodular disease are not very characteristic 

 during life. In fact, there must be thousands of fat sheep slaugh- 

 tered annually in the abattoirs of the country affected with this 

 ailment, which exhibit no special indications previous to being 

 tilled. But in the more advanced stages of the disease, the symp- 



