622 SCABIES — SCAB — MANGE. 



"When scab is generalised and it is impossible to define the parts 

 attacked, general treatment is indispensable and the diseased sheep 

 should be dipped. 



As a preliminary, however, and in order to make sure that the 

 application will produce its effect, the animals after shearing should 

 be passed, twenty-four hours before the medicinal bath, through a warm 

 bath containing soap in order to soften and remove the scabs. Appli- 

 cations of oil or some fatty substance will also soften the scabs, which 

 may afterwards be removed with a scraper without producing bleeding. 

 One pound of soft soap may be dissolved in fifty quarts of water and 

 each sheep plunged into this and scrubbed with a brush for a few 

 minutes. Washing alone removes a large number. of the parasites. 



Whatever bath be used it should not be given until four or five 

 hours after the last feeding. The dips most popular in France are 

 as follows : — 



Tessier's Bath (1810). 



/ Arsenious acid . . . . . . 1^ parts or lbs. 



For 100 sheep . . . . | Sulphate of iron . . . . 10 „ 



i Water 100 



i 



The above materials should be boiled for ten minutes, and, as a | 



consequence of the chemical fusion which occurs in the process, the | 



proportion of arsenious acid dissolved amounts to about 2 drachms | 



per quart instead of 3f drachms. | 



In this bath the arsenious acid acts as a parasiticide and the | 



sulphate of iron as an astringent, the latter checking the absorption | 



of toxic principles by the skin and sores, and preventing the sheep ^ 



from licking themselves. 1 



Absorption by the skin is not so dangerous as has been believed. }■ 



Eossignol has shown that poisoning need not be feared in chemical •^ 



baths unless the proportion of dissolved arsenic is above 150 grains ^ 



per quart, especially if the period of immersion does not exceed five J 



minutes. Even pure solutions of arsenic, free from any astringent, I 



may be used, provided the quantity in the bath does not exceed > 



120 grains per quart. J 



The bath should, if possible, be kept warm — 85° to 95° Fahr. '^ 



(30° to 35° C). 1 



Four men are generally employed for the operation. One drives 1 



in the sheep, two others hold and brush them in the bath, and the i 



fourth holds the head of the animal above the liquid. Tessier re- i 



commended gloves for the use of the operators, but experience has j 



shown that such a precaution is unnecessary. The udder, and par- j 



ticularly the teats, of ewes with yoang may, if necessary, be smeared > 



