PARASITES OF SHEEP 



D. S. BELT- 



Sheep parasites, both internal and external, are responsible toy 

 many deaths in the flock, gaining a foothold and often , performing 

 their deadly mission before their presence is detected. Some of 

 these parasites are easily controlled while others are eradicated 

 with great difficulty, if at all. Some of the treatments can be 

 given by the farmer without the aid of a specialist if he will follow 

 directions and recommendations. 



EXTERNAL PARASITES/ 



Numerous external parasites affect she^p, but the three whicla 

 are most common are ticks, lice, and mites. These can be eradi- 

 cated by following a definite plan of systematic dipping both spring 



and fall. In order to effect their 

 extermination something should 

 be known of their appearance and 

 llife history and the symptoms 

 I indicating their presence. 



The first symptoms shown by 

 the sheep indicating the presence 

 of external parasites are restless- 

 ness, rubbing against posts, 



and dark brown in color sheep bite and scratch themselves 

 in. an effort to get relief. The wool assumes a dry, harsh, and 

 ragged appearance. In advanced cases of infection with scab 

 mites there is often a loss of wool. 



Since these three parasites cause the same general symptoms, 

 it remains for a close and thorough examination of the affected 

 animal to reveal the particular kind of parasite or parasites pres- 

 ent. 



Tick. The common sheep tick, when mature, is about ene 

 eighth of an inch long and varies in color from a yellowish gray to 

 a dark brown. The tick is generally found in the greatest numbers 

 on the neck and shoulders. The pupae or so-called "eggs" are often 

 seen attached to the wool fibers. The period of incubation of the 

 eggs is from 18 to 24 days, but under abnormal conditions, this 



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