BUREAU OF ANIMAL INDUSTRY.. 131 



TREATMENT AND CONTROL OF EXTERNAL PARASITES. 



Hog MA^'GE. Investigations thus far have shown that hog manga 

 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 animals kept in pastures or in clean, well- 

 lighted, roomy pens or buildings; that if not controlled there is a 

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

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

 or arsenical solution with intervals of six or seven days between dip- 

 pings. 



Hog lice. In experimental work one dipping or treatment witii 

 crude petroleum or cottonseed oil usually proved effective in eradi- 

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

 CLted hog wallows, and it was found that when properlj constructed I 

 and used such w^allows provide an effective and convenient means of 

 treating hogs for lice and mange during hot weather. 



Caitle SCABIES. Fuitlicr experiments have confirmed former find- 

 ings as to the efficacy of four dipping's in lime-sulphur dip for the 

 treatment of sarcoptic scabies of cattle. Farmers' Bulletin 1017 on 

 cattle scab was issued. 



Spi^ose ear ticks. The pine-tar-cottonsecd-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 with 

 reference to the relative value of different kinds of dii:)s in protecting 

 sheep from infection with scabies. Dips containing sulphur appar- 

 ently protect a longer time than those not containing sulphur. 



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

 exU mined at frequent intervals, and both biting and sucking lice have 

 been found on eome of the animals in each herd every month in tho 

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

 more numerous and spread throughout the herd during the winter. 

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

 into winter quarters, even though 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 

 tapeworms and found only partly efficacious even Avhen used in 

 greater concentration than is used in the treatment for stomach 

 w^orms. 



In experiments to determine the most effective method of admin- 

 istering remedies to sheep Avitli a view of promptly reaching tho 

 fourth stomach, better results were obtained w^ith liquids than with 

 pills or capsules. Apparently, however, there is not nuich 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 with the sheep standing on all fours. 



Experiments in the use of carbon bisulphid against bots in horses 

 indicate that Gastrophilus intestinalis {G, eqid) is more readily 

 removed that G. nasal ts^ owing, presumabl}', to the location of many 

 of tlie G. nasalis in the duodenum, and that 6 drams in a single dose 



