The Prescott daily news., 1914-04-02
AN EXPERIMENT WITH TUBER-
CULOSIS

The problems presented by the wide
spread existence of tuberculosis in
dairy cattle are manifold. They bear
on human experience in connection
with the hygiene of the milk supply,
which is assuredly am after of no
small concern to all classes of society.
The question of tuberculosis in cattle
involves the economies of agriculture
to far greater degree than the I'M
initiated can appreciate; for the dis
ease has manifested itself so widely
that the hope of complete eradication
must be deferred for a long time, to
say the least. Furthermore, the out
come of the management of tubercu-
lous herds may point the way for ad-
vantageous applications in the field
of human treatment or prevention.
In view of the enormous practical
difficulties in the way of the complete
eradication of tuberculosis in cattle by
the wholesale slaughter of all ami
mails known to be infected with tuber-
culosis, schemes for utilizing the lat
ter have been devised. The most pro-
minent of these is the system whereby
tuberculosis cows are isolated and used
for breeding purposes, the calves be-
ing removed from the mothers at the
earliest moment and brought up with
outf urther exposure to the disease.
This has been rendered possible by the
finding that such young are regularly
born in perfect health, and entirely
free from tuberculosis. The affected
breeding cattle in this way do not be
come an entire economic loss. A ten
year investigation, carefully verified
and supervised by government Off
cials, has just been reported by Brooks
in connection with what is probably
one of thte most valuable herds of
Holstein- Friesian cattle in the world
The object was to produce herd
Of Holstein cattle free from tubercu-
losis faint and yet endowed with all
the most valuable strain characters
tics possessed by this breed. Animals
were selected because of their desira-
bility, entirely Independent Of the
presence or absence of tuberculosis.
The tuberculosis animals greatly out
numbered the non-tuberculosis. Three
hundred tuberculosis animals were
studied The existence of tuberculosis
was determined by the administration
of treble the official dose Of tubercu-
lin, repeated in no-reacting animasl
three times at intervals of six months,
All animals reacting to either test
were removed at once to the tu6crcu
losis farm so that there was no posi-
bility of the transmission Of infection
from the tuberculous group to the
healthy one. At birth thee aives are
Immediately taken from the mother.
Feelings are on pasturized milk col
lected Unfortunately from sound and
tuberculous animals.
OF more than two hundred calves
born of the tuberculous herd, rot one
has become tuberculous, although all
have been tested three times by mas
sive doses of tuberculin These ami
mails are rather more resistant to tn
berculosis than animals born of non
tuberculous parents. No falling off in
type, in milk production or fertility is
present in these calves, no increase in
death rate exists among them as com
pared with the offspring Of healthy
cattle, no falling off in value takes
place, and several of the most valu-
able cows and bulls in the world are
of this ancestry. Thes facts, says The
Journal of Americal Medical AssOcia-
ton, remain constant even where at
least three generations of known tu-
berculous parentage exist.