112
Abstract
[Vol XVIII, Part II
infection from 37 per cent and two such doses from 72 per cent of clinical cases. Two further treat
ments in persistent infections cured 80 per cent and this repeated in the reminder gave a 93 per cent
cure.
Nearly 95 per cent of the penicillin injected was absorbed from the udder tissue in about 12 hours
but an effective concentration remained after this period if the dose was not less than 15,000 units.
Treatment resulted in a transient fall in milk yield 13-37 per cent. The bacterial, and cell counts
were practically nil within 12-24 hours of treatment. Staphylococcal infection was less amenable to
treatment.
Stress is laid on maintaining a high standard of shed hygiene and milking methods if the penicillin
treatment is to prove effective.
(II)
Results are given of further trials with penicillin, treating six batches of 158 streptococcal and
staphylococcal mastitis cases by udder infusion. A preliminary dose of 25,000 units of penicillin
100 c.c. normal saline followed by two doses of 5,000 units at 12 hourly intervals cured 71 per cent of
clinical streptococcal mastitis cases. The percentage cure with three doses of 25,000 units in distilled
water was 78 to 93 in clinical mastitis due to Str. agalactiae, 100 due to non-group B, streptococci
and nil due to staphylococci. One single dose of 100,000 units in distilled water eliminated infection
in 38 per cent of clinical mastitis due to Str. agalactiae, in 25 per cent due to streptococcus non-group
B and in none due to staphylococcus. Three doses of 12,500 units in distilled water at 24 hour
intervals eliminated infection in 71 per cent of clinical mastitis due to Str. agalactiae and in 17 per cent
due to non-group B. streptococcus. Staphylococcal mastitis did not respond to treatment. Four
doses of 25,000 units in distilled water were tried in treatment of 2 cases of clinical staphylococcal
mastitis, without success. Three doses of 25,000 units in sterile peanut oil at 24 hour intervals proved
efficacious in eliminating infection from 94 to 100 per cent cases of clinical mastitis due to Str. agalactiae
but staphylococcal mastitis was not suppressed.
It was observed that an effective concentration of penicillin within the udder for two-three
days was more beneficial than a higher concentration for a shorter period. Although more than
three doses enhanced the percentage cure, it was not economical for the farmer.
Emphasis is laid on the inadequacy of penicillin alone in reducing the incidence of mastitis in
commercial dairy herds, other factors, particularly hygienic, are of dominant importance. (M.M.S.)
ROBERT L. SQUIBB (1946). A New Method for the Control of Cattle Ticks in Tropical Regions.
J. Am. Sci. Vol. 5, No. 1, February 1946, 71-79
T HIS paper reports the efficiency of a new combined solution of D.D.T. and derris for use as
spray in the control and eradication of cattle tick in tropical areas. Two solutions A and B
are prepared separately from D.D.T. and derris and used as a combined spray. The two solutions
are prepared as follows.
D.D.T.
.
.
.
.
Kerosine
.
.
.
.
Water
.
.
.
.
Neutral soap . . . .
6.16 gms.
66.6 c.c.
33.3 c.c.
1.8 gms.
Green crushed derris roots . .
Water
.
.
.
.
Neutral soap
.
.
.
.
22.5 gms.
200 c.c.
3.0 gms.
(a) Dissolve D.D.T. in kerosine and warm the solution. The water and neutral soap are mixed
and heated to 98ºC. This is then well mixed with D.D.T. solution. (b) Green crushed derris roots
or derris powder containing 5 per cent rotenone solution is extracted in water for 24 hours and filtered,
The neutral soap is dissolved in hot water, cooled and then added to the rotenone solution. Solution
B should be prepared just prior to use. The spray is made by mixing one part solution A to one part
solution B.