BUREAU OF ANIMAL INDUSTRY. 131 



TREATMENT AND CONTROL OF EXTERNAL PARASITES. 



Hog mange. — Investigations thus far have shown that hog mange 

 is spread mainly by direct bodily contact, that it spreads very rapidly 

 among hogs of low vitality kept in small inclosures, that it spreads 

 slowly among vigorous aninuils kept in pastures or in clean, well- 

 lighted, roomy pens or buildings; that if not controlled there is :-i 

 heavy loss from shrinkage, as well as from a high death rate; ant!, 

 finally, that it can be eradicated by four dippings in a lime-sulphur 

 or arsenical solution with intervals of six or seven da3's between dip- 

 pings. 



Hog lice. — In experimental work one dipping or treatment with 

 crude petroleum or cottonseed oil usually proved effective in eradi- 

 cating hog lice. Extensive experiments were carried on with medi- 

 ci.ted hog wallows, and it was found that wdien properly constructed 

 and used such wallows provide an effective and convenient means of 

 treating hogs for lice and mange during hot weather. 



Caiixe scabies. — Further experiments have confirmed former find- 

 ings as to the efficacy of four dippings in lime-sulphur dip for the 

 treatment of sarcoptic scabies of cattle. Farmers' Bulletin lOlT on 

 cattle scab was issued. 



Spinose EAit TICKS. — The pine-tar-cottonseed-oil remedy for ear 

 ticks recommended in Farmers' Bulletin 980 is being used extensively 

 in the Southwest with excellent results. 



Other external parasites. — Experiments are in progress wuth 

 reference to the relative value of different kinds of dips in protecting 

 sheep from infection with scabies. Dips containing sulphur appar- 

 ently protect a longer time than those not containing sulphur. 



Herds of lousy cattle in different sections of the country have been 

 examined at frequent intervals, and both biting and sucking lice have 

 been found on home of the animals in each herd every month in the 

 yeav. In summer they were found in small numbers, but they became 

 more numerous and spread throughout the herd duriiig the winter. 

 The advisability of treating cattle for lice in the fall, before they go 

 into Avinter quarters, even thougli they seem to be free from these 

 parasites, is thus apparent. 



ANTHELMINTICS AND TREATMENT FOR INTERNAL PARASITES. 



Copper-sulphate solution was tested in the treatment of sheep for 

 tapcAvorms and found only partly efficacious even when used in 

 greater concentration than is used in the treatment for stomacli 

 worms. 



In experiments to determine the most effective method of admin- 

 istering remedies to sheep with a view of promptly reaching the 

 fourth stomach, better results Avere obtained with liquids than Avith 

 pills or capsules. Apparently, hoAvever, there is not much uniformity 

 in respect to the passage of the dose to the fourth stomach, though 

 generally the dosing is more successful if the liquid is given slowly 

 and Avith the sheep standing on all fours. 



Experiments in the use of carbon bisulphid against bots in horses 

 indicate that GastrophiJus intestiiialis {G. cqui) is more readily 

 removed that G. nasalls, owing, presumably, to the location of many 

 of tlie G. nasalis in the duodenum, and that G drams in a single doso 



