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ABSTRACTS
(2) Protection of cattle from infection. This can be accomplished by fencing the
infected areas by preventing animals grazing on swamps and by total stoppage of feeding
the animals on forage obtained from infected areas. The author advocates ensilage as a
means of destroying the fluke cysts on vegetation. These cysts are destroyed within a
period of three months. Ensilage would thus permit the utilization of vegetation from
wet areas which would otherwise be useless.
(3) Treatment of cattle for flukes. The author tried Distol, Kamala, Hexachloroethane
and a mixture of the last two drugs. Of these the last one, viz. the mixture of Kamala
and Hexachlorethane, was found to be very efficient. Doses found most effective are
as follows :—One capsule of Distol to each 70 lb. of body weight, the total amount divided
into two equal doses. Ten grams of Kamala to each 60 lb. of body weight over a four-day
period. Ten grams of Hexachlorethane to each 60 lb. of body weight over a four-day
period. Of these drugs Kamala causes extensive diarrhœa and loss of appetite lasting
for a few days to about two weeks. Hexachloroethane causes colic when given at a high
concentration. The author found that a mixture of Kamala and Hexachloroethane in
the proportion of 1 .75 gm. : 10 gm. to each 70 lb. of body weight over two successive
days was well tolerated and was highly effective.
All the treated animals were found to have improved in general physical condition,
but a few lactating cows showed a slight decrease in milk production. lasting for one to
two weeks.
The author observes that the presence of approximately one egg in one gram of faeces
corresponds to one fluke harboured by an infected animal [G. D. B.]
On the function of tissue cells in media used for growing vaccinia virus.
H. B. MAITLAND and A. W. LAING (1941). J. Path. & Bact. 53, 419
A LL attempts to cultivate viruses in pure synthetic media have failed so far. The
add tion of certain specific tissue cells to the synthetic media, however, promotes the
growth of a virus. The exact function of these cells in the media is not yet known.
In this paper the authors have studied the relation between tissue and multiplication
of vaccinia virus in liquid media. They are of opinion that the function of cells in promot-
ing the growth of the virus in a medium containing minced rabbit kidney and Tyrode's
solution is twofold. The first concerns the property of cells necessary to initiate the growth
of the virus and the second concerns the multiplication of the virus in the later stages
of the culture. The former property can be arrested in several ways which damage the
cells, such as, by treatment with cyanide, by soaking in water and by incubating at 37° C.
in Tyrode's solution. Each of these treatments greatly reduces the respiratory activity
of the cells, but there does not appear to be any correlation between the amount of tissue
respiration and the growth initiating property of the medium. The failure of the treated
tissue to initiate virus growth is attributed to the cell damage of one kind or another, of
which the fall in respiration could be regarded as an indicator. This property of cells to ini-
tiate virus growth has been suggested to be similar to that of living cells which
protects virus from the action of antibody. Virus continues to multiply in a medium in
the later stages of culture when the growth initiating function of the same medium is lost.
The mechanism required to initiate virus growth and that which helps the continuation
of growth are thought to be different. [N. B. D.]
The effect of vitamin A and certain members of the B-complex upon calf
scours. PAUL H. PHILLIPS, NORMAN S. LUNDQUIST and PAUL D.
BOYER (1941). J. Dairy Sci. 24, 977
T HIS paper deals with the nutritional treatment of calf scours. The obser-
vations made by the authors are dealt with under separate sub-heads.
Symptoms. Scours or effusive watery diarrhœa was observed in calves of cows low
in vitamin C. The calves were apparently normal at birth. They were able to nurse
but usually went ' off feed ', between the second and seventh days with early evidence
of scours. Frequently the faeces bordered on the ' white ' type of scours and not in-
frequently there was some evidence of hæmorrhage. Often there was excessive lacri¬
mation, although this was not a constant symptom. The course of the disease usually