SOME PESTS OF OHIO SHEEP 77 



to attack goats, dogs and in rare cases, man. There is also a var- 

 iety of mite closely resembling the head scab mite of sheep which 

 commonly attacks goats. This latter variety has been found to at- 

 tack sheep, cattle, horses, swine and even man. 



Control. — In the early stages of the infection an application of 

 any of the dips recommended for common sheep scab may be ap- 

 plied directly to the infested parts. However, after the formation 

 of the crusts, it is advisable to soften them by the use of oil or 

 grease, and later to remove the scabs through the use of water and 

 alkali soap. Then apply any one of the following : — the lime and 

 sulphur dip, the tobacco dip, oil of cade, or Helmerich pomade 

 which is made as follows : — 



Sublime or precipitated sulphur 10 grams 



Potassium carbonate 5 grams 



Vaseline 40 grams 



FOOT SCAB MITE 



Symptoms. — This mite confines its attacks to the feet and 

 limbs. The mites spread very slowly from the first point of attack, 

 commonly the hind fetlocks, and ascend little by little the upper 

 part of the legs, rarely passing beyond the thighs. In infections of 

 long standing, however, they may invade the inner sides of the 

 thighs, the udder and the scrotum and in rare cases the front legs. 

 Early in the infestation the skin becomes inflamed and covered 

 with fine small scales, and later with yellowish white crusts. The 

 infested animals stamp their feet, scratch and gnaw at the infested 

 parts which action aids in producing sores and scabs. As the mites 

 multiply the yellowish-white crusts increase and become thicker, 

 and a later stage is reached in which the skin cracks. 



Description of Mites. — Under the crusts the parasites may be 

 found in abundance, but in order to readily detect them a magnify- 

 ing glass is necessary, for the mite only measures 310 to 400 micro- 

 millimeters by 250 to 260 micromillimeters. The mite lays its eggs 

 under the crusts. These may hatch in a short time into immature 

 forms which shed their skin several times before reaching 

 maturity. 



Control. — The mites appear to spread very slowly, both from 

 infested regions to healthy tissue and to other animals in the flock. 

 In an infested flock, only 2 to 3 percent of the sheep are attacked. 

 The remedies proposed for common sheep scab mite may be used to 

 combat the foot scab mite. 



DIPPING SHEEP 



By far the most effective method of combating external pests 

 of sheep consists in immersing the infested sheep in watery mix- 

 tures which will kill the parasites. Immersing sheep in a reliable 



