area were considered exposed. About 100,000 

 cattle were dipped in lindane, including some 

 5,000 outside the quarantined area dipped at 

 owners' requests. Thirty dipping vats were 

 used, 20 of them newly constructed because of 

 the outbreak. Infected herds were dipped 

 twice — exposed herds once — in temperatures 

 as low as —38 F. Reported losses were one 

 cow and six calves. One calf drowned, and five 

 were sick when dipped. Many of the animals 

 were in very poor physical condition when 

 treated. 



Movements from infected herds were traced 

 to destinations in California, Colorado, Idaho, 

 Illinois, Kansas, Nebraska, Utah, and Wyo- 

 ming. Cattle from infected Wyoming herds 

 had been moved to several premises in Idaho 

 and Nebraska. Inspections revealed one in- 

 fected herd in Bingham County, Idaho, and one 

 in Keith County, Nebr. Both herds were dipped 

 twice. Inspections did not reveal any evidence 

 of the disease in other Idaho and Nebraska 

 herds involved. The Idaho herds were treated 

 twice, except those in feedlots. They were in- 

 spected and held under quarantine until treated 

 or slaughtered. Cattle from infected Wyoming 

 herds received in other States were inspected 

 and no scabies was found. 



Mites on elk 



During 1960, mites identified as Psoroptes 

 equi var. cervinae were found on elk in Idaho 

 and in Wyoming. A skin condition was noticed 

 on the elk, which had been shot in Benewah 

 County, and a veterinary practitioner was 

 called. The veterinarian sent specimens to the 

 laboratory, where they were identified as psor- 

 optic. In Wyoming, scabies lesions were ob- 

 served w^hen members of the Game and Fish 

 Commission were putting elk through chutes 

 for tagging and identification purposes at the 

 Jackson Hole feeding grounds. Laboratory 

 studies confirmed that mites harvested from a 

 dead elk were psoroptic. Psoroptic mites have 

 been found over a period of many years on elk 

 and on bighorn sheep in several Western 

 States. 



The presence of scabies in wildlife suggests 

 that they may be a reservoir from which the 

 disease may spread to domestic animals. How- 

 ever, there has been no good evidence, at least 



during the recent years, that this has occurred. 

 Two requirements are necessary for this to 

 happen: (1) Mites on wildlife must be able to 

 propagate on domestic animals, and (2) they 

 must have the opportunity to spread from wild 

 to domestic animals. In this country, scabies 

 has not been observed to spread to domestic 

 animals from bighorn sheep or elk, and out- 

 breaks during recent years in cattle and sheep 

 are not believed to have been caused in this 

 manner. The problem deserves further study. 



Field trials — cold lime-sulfur dips 



During recent years, public attention has 

 been drawn to the problem of chemical resi- 

 dues laid down in tissue through treatment of 

 animals. It is also recognized that some acari- 

 cides made available for the control of scabies, 

 ticks, or both might not be effective eradica- 

 tion agents. 



Following careful study of these related 

 problems, it was decided to conduct field trials 

 in an effort to prove the efficacy of dips as 

 eradication agents and to determine whether 

 a variation of dipping methods or procedures 

 might reduce the tissue-residue hazards to hu- 

 man health. Consequently, in March and April 

 1960, field trials were conducted in Iowa to de- 

 termine whether cold liquid lime-sulfur plus a 

 wetting agent could be used effectively in sheep 

 scabies eradication. Eight infected and quar- 

 antined flocks totaling 411 sheep wei'e selected 

 in widely scattered communities. Sheep were 

 dipped twice at 10- to 13-day intervals regard- 

 less of temperature and weather, or age and 

 physical condition of the animals. 



The trials indicated that healthy lambs and 

 adult sheep could be dipped in cold liquid lime- 

 sulfur bath at 29 F., in an atmospheric tem- 

 perature of 16°, with no deleterious effects. 

 The addition of the wetting agent Triton GR 

 5 at 13 ounces to 100 gallons of water gave 

 complete dip penetration and kept fleece damp 

 for 4 to 5 days thereafter. Farm waters, re- 

 gardless of degree of harshness, did not disturb 

 the equilibrium of the lime-sulfur solution. Im- 

 mersion of adults for 3 minutes and lambs for 

 1 to I'o minutes in a bath maintained at not 

 less than 2-percent "sulfide-sulfur" concentra- 

 tion, killed mites within 24 to 48 hours follow- 

 ing first dipping. Inspections were made at 



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