THE ANIMAL PAEASITES OF CATTLE. 



By B. H. Ransom, Ph. D., 



Chief of Zoological Division, Bureau of Animal Industnf. 



The animal j)arasites of cattle comprise more than a hundred 

 different species, belonging to various groups of the animal king- 

 dom. Fortunately not all of these parasites occur in this country — 

 many are uncommon, and many are comparatively harmless. Some 

 forms, however, occur frequently, and some are of distinct impor- 

 tance to the American stockman on account of the damage for which 

 they are responsible. It is these parasites particularly which will 

 be considered in the present article, and although some forms are 

 discussed which are rare or apparently of little economic importance, 

 most of the minor and unusual parasites and species not found in 

 this country have been neglected. 



FLIES.^ 



Of the various species of flies which infest cattle some are inju- 

 rious on account of the annoyance, pain, and loss of blood due to 

 their bites, and sometimes also on account of diseases or parasites 

 which are thus transmitted from the blood of diseased animals to 

 the blood of healthy cattle, while others, which in the winged adult 

 state do not bite, are injurious because they live parasitic in cattle 

 during their larval stages. 



Remedies for flies. — There are various remedies to be had, which 

 are more or less efficient in protecting cattle from the attacks of flies. 

 Most of them have to be applied frequently, and few, if any, will 

 keep flies away for more than a day or two following their applica- 

 tion. The following mixtures may be made at an average cost of 

 35 to 50 cents per gallon. The numerous proprietarj'^ fly repellents to 

 be found on the market are usually more expensive, and often less 

 efficient. 



At the Minnesota Experiment Station rancid lard 1 pound and 

 kerosene one-half pint, mixed thoroughly until a creamy mass 

 forms, was found to give excellent results as a fly repellent, lasting 



1 Further information may be found in a very full report on " Insects Affecting Domestic 

 Animals," issued as Bulletin 5, new series, of the Bureau of Entomology of this depart- 

 ment. 



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