\(,2 ANNUAL REiFOKT OP TH& Oft. DoC. 



earned etiuu-^h iiioue}- by the production of the biological products 

 iihovc ciiwiiicrulfd to pay Iheir cost of maiuleuauce. Ol' coiuse, none 

 ol' llifsc products were sold, but if tliej bad not been produced in the 

 laboratory it would have been necessary for the State to pay for them 

 as much as the laboratory cost. 



The comparative study of tubercle bacilli from human and bovine 

 sources has been continued and the latest report upon this subject 

 liv Dr. -Mazvck i'. Kavenel will be found below. It is believed that 

 the investiy;atiotis upon which this report is based have been con- 

 ducted for a longer time and are more comprehensive than similar 

 investigations made in any other part of the world. As the work 

 has been done with the utmost care there is reason to have coulideuce 

 ill the conclusions that are stated. 



Tuberculosis. — This is still the most widespread and dangerous 

 disease among cattle in rennsylvaiiia. It is estimated that the 

 losses from this disease amount to from f2,UUU,000.U0 to $3,000,000.00 

 a year. Ihis total is large, but it is believed to be a conservative 

 estimat'.- and upon analysis it will appear that it is by no means 

 improbable. There are in the State about 225,000 farms and an aver- 

 age loss of $10 a farm would make a total of $2,250,000.00. If the 

 average value of a dairy cow is $40, it will be seen that the loss of 

 such a cow is equivalent to an average loss of $10 a farm for four 

 farms; but it is not uncommon for ten cows to be lost as a result of 

 tuberculosis; this means a total loss of $400, or an average loss of $10 

 a farm for forty farms. In one herd this year, the losses from tuber- 

 culosis amounted to $5,000, which is equivalent to a loss of $10 a farm 

 for 500 farms. Undoubtedly, the losses from tuberculosis are now 

 much smaller than they were a few years ago, and the disease is 

 believed to be practically eradicated from man^^ parts of the iState; 

 the parts where the herd owners themselves have taken the most 

 active interest in repressing this scourge. But the losses are still 

 very great and the disease is still often spread from herd to herd 

 through the sale of tubercular cattle. The distribution of disease 

 that formerly resulted from this cause has been checked in so far as 

 cattle fro'n outside of Pennsylvania are concerned. It is required 

 thai these, if intended for the dairy or for breeding purposes, shall 

 be inspected before they are sold. The effect of this law is most 

 beneficial and 1 reproduce here an analysis of its results based upon 

 a most liberal estimate as to the cost of its operation and a most 

 conservative estimate of its value to live stock owners. The quota- 

 tion is taken from my annual report for the year 1900. 



'The increased cost of inspected cows is equivalent to the cost of 

 the inspeciion. This averages about fifty cents per head. In order 

 that all possible collateral expenses may be surely covered, the ex- 

 treme figure of $1.00 per head may be taken as the basis for this 



