116 DISEASES or SHEEP. 



are found in greater or less quantities, enveloped in tough 

 mucus. If one or more lambs have died of the disease, 

 and show the same results on- dissection, it may be concluded 

 that the other sick lambs of the flock suffer from the same 

 disease if they exhibit the same symptoms. 



If the disease has not progressed too far, and the lambs 

 retain a certain aniount of vigor and appetite, a cure fre- 

 quently succeeds. Half a teaspoonful of a mixture of 

 purified hartshorn oil and turpentine, each half an ounce, 

 and brandy four ounces, is given twice a day for several 

 days in succession, and the remainder of the treatment is 

 like that for lung worms. 



THE LARV^ OF THE GADFLY. 



The gadfly, or osstrus, is found during the whole summer 

 near the pasture-grounds of sheep, and annoys them, es- 

 pecially in hot weather and at noon. It has not been as- 

 certained at what point of the sheep's body it deposits its 

 eggs, but it is probably at the nose and lips. It is fre- 

 quently observed that the animal, after a gadfly has left it, 

 shakes its head violently, stamps with its feet, rubs its nose 

 on the ground, runs about, sneezes, hangs down its head and 

 looks terrified. When the sheep are seen to stand closely 

 together in mid-day heat with their noses on the ground, it 

 is probably for the purpose of preventing the oestrus from 

 reaching their noses and lips. 



As soon as the larvae are hatched from the eggs, they 

 crawl up through the nose to the sinus of the frontal or of 

 the maxillary bone, into the cells of the ethmoid bone or 

 into the cavities of the uvula. They attach themselves to 

 the mucous membrane by means of their hooks, and live on 



