The Washington herald., 1907-07-28
DIR. MELK EXPLAINS
TUBERCULIN TEST.

Editor The Washington Herald:
! In The Washington Herald Of July q
the opinions Of several leading milk deal
ers are given on the subject Of the pro-
posed regulations for controlling the pro-
ductlon and distribution OF the city's milk
supply.
Upon one point-the tuberculin test-the
parties interviewed seem TO speak with
great unanimity. but although agreed
upon the matter under consideration, all
who mention the tuberculin test display
the same lack OF understanding with re-
gard TO It, and also show that they have
| all derived their schooling and prompting
/ in the matter from the same source. To
one who knows that some thirty-slx hours
are required for the proper application Of
the taberculin test. the repeated sugges-
/ ton that this test, IN order TO be effective
must be made before each milking, can
only appear absurd. challenge this por-
/ tion of their interview, and assert that no
proof can be furnished in its support from
any authentic source. II is evident that
this inference is made primarily to dis
credit the practicability of the test
AS a matter of fact no one familiar
with the use Of tuberculln would think Of
retesting a COW until after at least six
weeks had elapsed. for the simple reason
that even tuberculous cows will not react
TO second test If made too soon after
the first test. Tuberculin only searches
the COW for the presence Of tuberculosis
Other diseased conditions are not detect
ed by this agent but when properly used
( 1t Is SO certain to give warning when
ever this disease IS present that COW
which fails TO react to its application n-
/ der normal dairy conditions may with
perfect assurance, be considered free from
tuberculosis. Such being the case, size
cannot develop the disease until living
| tubercle germs have been brought into
her system. and this fact Is one which
/ affords such great confidence to the sani-
/ tarians IN their hope that tuberculosis
/ may ultimately be eTadicated from the
herds supplying milk 10 our cities And
/ II is evident mat II a herd is free from
/ the disease. IL viii remain free so long as
/ cleanliness in the care Of the stables and
caution in buying new members for the
I herd succeed Ia keeping these deadly
germs from the premises
Cattle that are inoculated with large
numbers Of virulent tubercle germs, for
experimental purposes. may withstand the
attacks of the bacilH for months; and
when the source Of infection is limited to
/ the relatively small number Of germs that
will be taken Up by natural infection due
/ 20 keeping cattle in contaminated stables
/ or with tuberculous companions il must be
evident that tuberculosis will not develop
10 any serious extent in the interim be-
tween tubercul!n tests as recommended
/ by the Agricultural Department.
tuberculosis Of cattle, ike consumption
/ In the human subject. is a disease Of
slow, insidious invasion It win not de-
yelop in the healthy COW overnight, as
/ does smallpox or scarlet fever in man. or
/ between the morning and evening milking
hours, and the dl Try herd which fails 10
react 20 yearly tuberculin tests NAV
safely be considered free from tubereu-
Z losis with its attendant dangers and
los es.
Tuberculin IS not infaulble, and il is not
/ claimed 20 be by It's most ardent advO-
Gates, but it is claimed To be infaIlibIe I'm
g per cent Of the cases tested by qualified
men, which percentage is based upon test
records Of thousands Of animals. Can
man himself claim higher degree Of IN
fallibllty. as without the assistance OF
this agent but small percentage Of the
cases Of tuberculosis In cattle could be
de-ected2 Very respectfully.
A. d. MELVIN
Chief Of Bureau Of Animal Industry. Department Of
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