398 UNIVERSlTi' OF VIRGINIA PUBLICATIONS 



First among the causes responsible for the poor condition of our sheep 

 must be placed insufficient food, and second parasitic diseases. These 

 two causes alone and in various combinations deserve the most careful 

 consideration. 



Insufficient food. It is beyond the scope of this article to discuss in de- 

 tail the subject of sheep feeding. However, there was much evidence ac- 

 quired during 1903 and 1904 which indicated that overstocking of the 

 ranges was common. Frequently it appeared that there were too many 

 animals on the ranges, and at the same time that the area of available 

 range was becoming reduced. I was told by some men that the supply of 

 natural forage was much less than it had been twelve and fifteen years 

 earlier, and that the range grass was never given time to attain its growth 

 before it was used again for grazing. I was told that it was not generally 

 customary to rely upon alfalfa and other cultivated crops for food for the 

 stock during inclement weather and at times when the range grass was 

 scanty. I also learned that ranchmen raising large crops of alfalfa suffered 

 relatively small losses from loco disease. In one instance I had a chance to 

 observe that one division of a large flock of sheep grew thin and suffered 

 severe^ from loco disease on the scanty forage of the plains, while another 

 division of the same flock grew fat and prospered on the richer forage of the 

 uplands. This evidence and more like it makes me agree with those ranch- 

 men who hold that there is not enough natural forage to support all the 

 live stock depending upon it, and that, therefore, malnutrition, or even 

 starvatiop is not infrequent among the stock. In addition to this it was 

 easy to observe, by watching flocks of sheep feeding, that the small and 

 weak members of the flock are at a great disadvantage. In a flock of several 

 thousand, the sheep, when feeding, are always on the move, staying to- 

 gether, several columns deep. The stronger animals keep to the front and 

 get the best forage; the weaker animals at the rear eat what is left — which 

 is poor rations when the range is short. 



Parasitic diseases. Several of the parasites found in the "locoed" sheep 

 occasionally produce serious losses. The fringed tape worm {Thysanosmna 

 actinioides) , the lung worm, and the fly larvae {Oestrus ovis) are weU known 

 scourges. The wire worm of the stomach is a newly discovered parasite 

 and its exact relation to disease is unknown. Since it is very much like the 

 Strongylus contortus, it seems probable that its effects will be similar. The 

 Strongylus contortus causes widespread losses among sheep. 



That sheep are infected with parasites does not mean that they must 

 necessarily die of the infection. The severity of the resulting disease de- 

 pends upon a number of factors, such as the age of the animal — j^oung 

 animals suffering more than full growns; the general nutrition and health of 



