Evening star., 1926-08-13
WARNS OF KILLING
TUBERCULAR COWS
Patho|ogist Feels Removal
Will Develop Weak Stock.
Another Disputes Claim.

Special Dispatch to The Star.

CHICAGO, Aug. 13.-That a whole
sale slaughter of tuberculous infected
| cattle might tend to develop a stock
| with poor resistance to the ravages of
disease is the warning issued by DR..
Esmond r. Long, pathologist of the
University of Chicago. The slaughter
ing of infected cattle eliminates ami
mails that have become accidentally in
fected. DR.. Long said, without some
assurance that the disease will not re-
turn in more serious form.
In so far as possible infected cattle
should be replaced by those of a
known high resistance to tuberculosis
otherwise the Strengthening of acCi-
dentally infected cattle has a tendency
to produce q stock with a low degree
of resistance, and with this condition
there is always an acute danger of
sporadic epidemics, he said. Through
long period of selective breeding a
high degree of resistance might be
built up. much as the majority of hui
man beings are today resistant through
the survival of the fitteSt, but the ex-
tent to which this might be practiced
in profitable dairying is questionable,
since the most resistant stocks are not
the best dairy cattle, he admitted.
Tells of Vaccination.
DR.. Long said that although vac
cination of cattle has not yet proved
successful, it still holds out possibili-
ties of solving some of the pressing
problems.
I'm the past" he added. sit has not
been possible to control the vaccinat-
ing infection. but extended investiga-
ton is now in progress, and among
others a FrenChman, Calmette, claims
encouraging results with the inOcula-
tion of both calves and human infants
with living tubercle bacilli from a
strain of reduced virulence."
DR.. Long expressed lack of convic
ton about the Frenchman's' expert
| ments and pointed out the necessity OF
further investigation. "Only by elabo
rate trial can we ever satisfy our
selves of the simultaneous safety and
effectiveness of any recommended pro
cedure Of this character" he con
| cluded.
Disagreement with DR.. Long or
certain points in his theory was ex
pressed by J. A. Herman, chief of the
| tuberculosis eradication division OF the
| United States Bureau of Animal In
dustry.
/ Denies His Conclusions.
| THE bureau has for many years
| been engaged in cooperating with the
| live stock owners through State live
stock sanitary officials in the control
and suppression of bovine tubercu
losis," Mr. Kiernan said without
referring particularly to specific rec
ords, 1 can say it is the general OBJ
servation that during a period Of sev'
eral years herds with infection vary
ing from | to so per cent have been
under supervision--that is, the cattle
comprising those herds have been
tuberculin tested. the reactors re-
moved and the non-reacting cattle kept
in the herd. Those same herds, de
pleted by the removal of tuberculous
cattle, have been rehabilitated by addi-
tional animals. If there was any
lowering in the resistance of the re-
constructed herds, compared with
other herds, it has not been noted:
II would like to call attention also
to the fact that in a number of States
there are thousands of herds that have
/ never been infected or exposed to
bovine organism. When infection is
introduced into those herds through
the importation of tuberculous cattle
from other States the infection does
not seem to spread any more rapidly
than in herds in other localities