THE ANIMAL PAKASITES OF CATTLE. 



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

 Chief of Zoological Division, Bureau of Animal Industry. 



The animal parasites of cattle comprise more than a hundred dif- 

 ferent species, belonging to various groups of the animal kingdom. 

 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 importance to 

 the American stockman on account of the damage for which they are 

 responsible. It is these parasites particularly which will be consid- 

 ered 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 injurious 

 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 application. The 

 following mixtures may be made at an average cost of 35 to 50 cents 

 per gallon. The numerous proprietary fly repellants to be found on 

 the market are usually more expensive, and often less efficient. 



At the Minnesota Experiment Station rancid lard, 1 pound, and kero- 

 sene, one-half pint, mixed thoroughly until a creamy mass forms, was 

 found to give excellent results as a fly repellant, lasting for two or 

 three days, when rubbed not too thickly over the backs of cows with 

 a cloth or with the bare hand. Similar good results were obtained by 

 applying a mixture of three parts of fish oil and one of kerosene, with 

 a small spray pump. A mixture of two parts of crude cotton-seed oil 

 or fish oil, with one part of pine tar, applied with a large paint brush, 



"■ 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 department. 



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