NationalLibraryOfScotland/medical-history-of-british-india huggingface dataset:
276 THE INDIAN JOURNAL OF VETERINARY SCIENCE AND ANIMAL HUSBANDRY [ I, IV
TABLE X.
Pit No. 3.—Percentage composition of prime Jowar. Before and after ensilage—
on dry basis. Rapid filling with watering.
Constituents
* Crude protein
* Ether extract
.
Nitrogen free extractives
Crude fibre......
Ash
Silica......
True protein
Amides
Bag 5
Green
Jowar
7.52
1.64
53.25
31.51
6.08
2.55
5.65
1.87
Silage
8.28
2.67
44.25
35.62
9.18
3.85
4.59
3.69
Bag 7
Green
Jowar
8.83
1.82
50.14
31.63
7.58
3.32
6.92
1.91
Silage
9.28
2.73
45.51
33.05
9.43
4.40
4.90
4.38
* Uncorrected.
TABLE XI.
Pit No. 4.—Percentage composition of prime Jowar. Before and after ensilage—
on dry basis. Rapid filling without watering.
Constituents
* Crude protein......
* Ehter extract.....
Nitrogen free extractives
.
.
.
.
.
Crude fibre.....
Ash......
Silica......
True protein......
Amides.......
Bag 9
Green
Jowar
7.19
1.26
50.16
34.52
6.87
2.22
4.78
2.41
Silage
8.18
2.80
43.87
35.64
9.51
3.85
3.60
4.58
Bag 11
Green
Jowar
7.74
1.43
50.34
33.31
7.18
3.06
5.76
1.98
Silage
8.51
2.44
45.92
33.97
9.16
3.50
5.19
3.32
* Uncorrected.
SILAGE INVESTIGATIONS AT BANGALORE
277
TABLE XII.
Pit No. 1.—Changes in the various constituents of prime Jowar during ensilage (in
gms. on dry basis), slow filling with watering.
Constituents
Total dry matter .
Organic matter
.
Total carbohydrates .
Nitrogen free extrac-
tives.
Crude fibre . .
*Ether extract . .
†Crude protein . .
True protein . .
Amides .
.
.
Total ash . . .
Ash soluble in HCl .
Silica . . .
Bag 13
Green
Jowar
5,294.0
4,954.4
4,370.1
2,645.5
1,724.6
157.1
427.2
327.6
99.6
339.6
211.0
128.6
Silage
4,955.0
4,615.4
3,794.5
2,151.1
1,643.4
433.5
387.4
186.3
201.1
339.6
192.4
147.2
Gain or
loss
Per cent.
— 6.4
— 6.8
— 13.2
— 18.7
— 4.7
+ 175.9
— 9.3
— 43.1
+ 101.9
0.0
— 8.8
+ 14.5
Bag 17
Green
Jowar
4,685.0
4,160.9
3,754.4
2,264.7
1,489.7
130.4
276.1
206.0
70.1
524.1
190.2
333.9
Silage
4,389.0
4,004.4
3,468.3
2,034.8
1,433.5
262.3
273.8
169.1
104.7
384.6
180.8
203.8
Gain or
loss
Per cent.
— 6.3
— 3.8
— 7.6
— 10.2
— 3.8
+ 101.1
— 0.8
— 17.9
+ 49.4
— 26.6
— 4.9
— 39.0
Average
gain or
loss
Per cent.
— 6.3
— 5.3
— 10.4
— 14.4
— 4.2
+ 138.5
— 5.0
— 30.5
+ 75.6
— 13.3
— 6.8
— 12.2
* Corrected for loss of volatile organic acids.
† Corrected for loss of volatile bases.
TABLE XIII.
Pit No. 2.—Changes in the various constituents of prime Jowar during ensilage
(in gms. on dry basis), slow filling without watering.
Constituents
Total dry matter .
Organic matter . .
Total carbohydrates .
Nitrogen free extrac-
tives . . .
Crude fibre . .
*Ether extract . .
†Crude protein . .
True protein . .
Amides . . .
Total ash . . .
Ash soluble in HCl .
Silica
.
. . .
Bag 15
Green
Jowar
5,775.0
5,439.7
4,918.4
2,853.9
2,064.5
145.2
376.1
281.8
94.3
335.3
220.1
115.2
Silage
5,519.0
5,177.3
4,495.2
2,519.2
1,976.0
309.1
373.0
160.7
212.3
341.7
226.5
115.2
Gain or
loss
Per cent.
— 4.4
— 4.8
— 8.6
— 11.7
— 4.3
+ 112.9
— 0.8
— 43.0
+ 125.1
+ 1.9
+ 2.9
0.0
Bag 19
Green
Jowar
5,486.0
5,100.7
4,594.6
2,800.9
1,793.7
150.9
355.2
239.3
115.9
385.3
215.4
169.9
Silage
4,941.0
4.585.7
4,044.3
2,454.7
1,589.6
167.9
373.5
244.5
129.0
355.3
214.1
141.2
Gain or
loss
Per cent.
— 9.9
—10.1
—12.0
—12.4
—11.4
+ 11.3
+ 5.2
+ 2.2
+ 11.3
— 7.8
— 0.6
—16.9
Average
gain or
loss
Per cent.
— 7.1
— 7.4
—10.3
—12.0
— 7.8
+62.1
+ 2.2
—20.4
+68.2
— 2.9
+ 1.1
— 8.4
* Corrected for loss of volatile organic acids.
† Corrected for loss of volatile bases.
C 2
278 THE INDIAN JOURNAL OF VETERINARY SCIENCE AND ANIMAL HUSBANDRY [ I, IV
TABLE XIV.
Pit No. 3.—Changes in the various constituents of prime Jowar during ensilage (in
gms. on dry basis), rapid filling with watering.
Constituents
Total dry matter .
Organic matter . .
Total carbohydrates .
Nitrogen free extrac-
tives.
Crude fibre . .
*Ether extract . .
† Crude protein . .
True protein . .
Amides . . .
Total ash . . .
Ash soluble in HC1 .
Silica . . .
Bag 5
Green
Jowar
7,292.0
6,856.6
6,066.6
3,810.6
2,256.0
223.2
566.8
404.8
162.0
435.4
252.9
182.5
Silage
6,237.0
5,714.2
4,499.8
2,470.7
2,029.1
627.3
587.1
261.6
325.5
522.8
303.3
219.5
Gain or
loss
per cent.
— 14.5
— 16.7
— 25.8
— 35.2
— 10.1
+ 181.1
+ 3.6
— 35.4
+ 100.9
+ 20.1
+ 19.9
+ 20.3
Bag 7
Green
Jowar
6,763.0
6,256.3
5,463.9
3,349.4
2,114.5
189.6
602.8
462.6
140.2
506.7
284.7
222.0
Silage
5,764.0
5,252.7
4,238.4
2,446.4
1,792.0
441.7
572.6
265.6
307.0
511.3
272.7
238.6
Gain or
loss
per cent.
— 14.8
— 16.0
— 22.4
— 27.0
— 15.3
+ 133.0
— 5.0
— 42.6
+ 119.0
+ 0.9
— 4.2
+ 7.5
Average
gain or
loss
per cent.
— 14.6
— 16.3
— 24.1
— 31.1
— 12.7
+ 157 0
— 0.7
— 39.0
+ 109.9
+ 10.5
+ 7.8
+ 13.9
* Corrected for loss of volatile organic acids.
†
Corrected for loss of volatile bases.
TABLE XV.
Pit No. 4.—Changes in the various constituents of prime Jowar during ensilage (in
gms. on dry basis), rapid filling without watering.
Constituents
Total dry matter .
Organic matter . .
Total carbohydrates .
Nitrogen free extrac-
tives.
Crude fibre . .
Ether extract* . .
Crude protein† . .
True protein . .
Amides . . .
Total ash . . .
Ash soluble in HCl .
Silica . . .
Bag 9
Green
Jowar
5,915.0
5,520.7
4,859.5
2,877.0
1,982.5
240.3
420.9
274.6
146.3
394.3
267.1
127.2
Silage
5,509.0
5,013.6
4,126.6
2,269.3
1,857.3
391.4
495.6
187.4
308.2
495.4
294.9
200.5
Gain or
loss
Per cent.
— 6.9
— 9.2
— 15.1
21.1
— 6.3
+ 62.9
+ 17.7
— 31.8
+ 110.7
+ 25 6
+ 10.4
+ 57.6
Bag 11
Green
Jowar
6,205.0
5,770.1
5,066.6
3,048.2
2,018.4
222.9
480.6
349.0
131.6
434.9
249.6
185.3
Silage
5,633.0
5,140.8
4,277.9
2,453.3
1,824.6
339.6
523.3
279.0
244.3
492.2
304.3
187.9
Gain or
loss
Per cent.
— 9.2
—10.9
—15.6
—19.5
— 9.6
+52.4
+ 8.9
—20.1
+85.6
+ 13.2
+21.9
+ 1.4
Average
gain or
loss
Per cent.
— 8.0
—10.0
—15.3
—20.3
— 7.9
+ 57.6
+13.3
—25-9
+98.1
+ 19.4
+16.1
+29.5
* Corrected for loss of volatile organic acids.
†
Corrected for loss of volatile bases,
SILAGE INVESTIGATIONS AT BANGALORE
279
TABLE XVI.
True protein expressed as percentage of crude protein.
Type of ensilage
Prime Jowar silage, slow filling with
watering. Pit No. 1.
Prime Jowar silage, slow filling without
watering. Pit No. 2.
Prime Jowar silage, rapid filling with
watering. Pit No. 3.
Prime Jowar silage, rapid filling without
watering. Pit No. 4.
Bag No.
13
17
Average
15
19
Average
5
7
Average
9
11
Average
Green Jowar
76.63
74.76
75.76
74.93
67.37
71.15
71.42
76.74
74.08
65.24
72.62
68.93
Silage
48.09
61.76
54.92
43.08
65.46
54.27
44.56
46.39
45.47
37.81
53.31
45.56
TABLE XVII.
Changes in volatile bases and amino acids during ensilage.
Type of ensilage
Prime Jowar silage, slow filling
with watering. Pit 1.
Prime Jowar silage, slow filling
without watering. Pit 2.
Prime Jowar silage, rapid filling
with watering. Pit 3.
Prime Jowar silage, rapid filling
without watering. Pit 4.
Bag
No.
13
17
15
19 5
7
9
11
Volatile bases
Green
Jowar
13.8
12.1
20.0
8.2
28.1
12.4
8.2
11.7
Silage
75.9
44.1
57.9
39.7
115.5
69.7
69.6
66.5
Amino acids
Green
Jowar
55.2
24.2
103.9
65.5
177.8
165.4
40.8
116.8
Silage
132.8
66.1
94.1
53.0
207.8
149.3
89.5
123.5
Asparagin
Green
Jowar
67.7
85.4
60.3
98.9
56.5
74.9
73.8
64.6
Silage
42.9
22.2
32.8
10.0
34.9
30.0
15.0
..
280 THE INDIAN JOURNAL OF VETERINARY SCIENCE AND ANIMAL HUSBANDRY [ I, IV
TABLE XVIII.
Ratio of volatile bases to amino acids before and after ensilage.
Type of ensilage
Prime Jowar silage, slow filling with water-
ing. Pit 1.
Prime Jowar silage, alow filling without
watering. Pit 2.
Prime Jowar silage, rapid tilling with water-
ing. Pit 3.
Prime Jowar silage, rapid filling without
watering. Pit 4.
Bag No.
13
17
Average
15
19
Average
5
7
Average
9
11
Average
Green Jowar
0.25
0.50
0.38
0.19
0.13
0.16
0.16
0.08
0.12
0.20
0.10
0.16
Silage
0.57
0.67
0.62
0.62
0.75
0.68
0.56
0.47
0.51
0.78
0.54
0.66
TABLE XIX.
Changes in organic acids during ensilage.
Pit No. and
conditions of
ensilage
Pit No. 1. Slow
filling
with
watering.
Pit No. 2. Slow
filling without
watering.
Pit No. 3. Rapid
filling
with
watering.
Pit No. 4. Rapid
filling without
watering.
Bag No.
13
17
Average
15
19
Average
5
7
Average
9
11
Average
Volatile organic acids
(as acetic acid)
Green
Jowar
85.2
52.7
..
85.0
56.2
..
105.9
68.1
..
167.8
136.2
..
Silage
318.8
181.5
..
188.7
95.4
..
475.2
293.6
..
245.5
208.6
..
Increase
per cent.
274.2
244.8
259.5
122.0
69.8
95.9
348.7
331.1
339.9
46.3
53.2
49.7
Non-volatile organic acids
(as lactic acid) gms.
Green
Jowar
67.4
83.1
..
92.7
..
...
..
..
..
..
..
Silage
117.1
166.3
...
141.5
143.1
..
344.6
276.5
..
112.5
224.9
..
Increase
per cent.
58.9
100.1
79.5
0.0
54.4
..
0.0
0.0
..
0.0
0.0
..
SILAGE INVESTIGATIONS AT BANGALORE
281
TABLE XX.
Ratio of volatile to non-volatile organic acids in silage.
—
Ratio
Pit No. 1. Slow
filling with
watering
Bag
13
2.722
Bag
17
1.091
Aver-
age
1.906
Pit No. 2. Slow
filling without
watering
Bag
15
1.334
Bag
19
0.667
Aver-
age
1.000
Pit No. 3. Rapid
filling with
watering
Bag
5
1.379
Bag
7
1.062
Aver-
age
1.220
Pit No. 4. Rapid
filling without
watering
Bag
9
2.182
Bag
11
0.927
Aver-
age
1.554
TABLE XXI.
Pit No. 1.—Changes in the minerals of prime Jowar during ensilage (in gms.). Slow
filling with watering.
Constituents
P 2 O 5 . .
CaO . .
MgO . .
SO 3 . . .
KCl + NaCl .
Green
Jowar
25.7
14.3
19.2
6.7
66.7
Bag 13.
Silage
23.1
14.8
11.7
3.4
149.2
Gain or
loss
per cent.
— 10.12
+
3.50
— 39.06
— 49.23
+ 123.69
Green
Jowar
19.8
15.6
14.5
4.0
150.3
Bag 17.
Silage
20.8
15.2
13.2
4.7
123.6
Gain or
loss
per cent.
+ 5.05
— 2.56
— 8.97
+ 22.5
—17.76
Average
gain or
loss
per cent.
— 2.53
+ 0.47
—24.01
—13.36
+52.96
TABLE XXII.
Pit No. 2.—Changes in the minerals of prime Jowar during ensilage (in gms.). Slow
filling without watering.
Constituents
P 2 O 5 . .
CaO . .
MgO . .
SO 3 . . .
KC1 + NaCl .
Green
Jowar
24.4
14.0
19.6
5.5
116.0
Bag 15.
Silage
25.5
16.3
18.2
4.3
185.7
Gain or
loss
per cent.
+ 4.51
+ 16.43
— 7.14
—21.82
+ 60.09
Green
Jowar
28.1
16.9
17.0
5.5
174.2
Bag 19.
Silage
26.4
20.1
16.4
4.8
152.9
Gain or
loss
per cent.
— 6.05
+ 18.93
— 3.53
—12.73
—12.23
Average
gain or
loss
per cent.
— 0.77
+ 17.68
— 5.33
—17.27
+23.93
282 THE INDIAN JOURNAL OF VETERINARY SCIENCE AND ANIMAL HUSBANDRY [ I, IV
TABLE XXIII.
Pit No. 3.—Changes in the total minerals of prime Jowar during ensilage (in gms.).
Rapid filling with watering.
Constituents
P 2 O 5 .
.
.
CaO .
MgO .
SO 4 .
KC1 + NaCl.
.
Green
Jowar
35.5
24.9
27.3
4.7
132.3
Bag 5
Silage
35.1
22.5
19.7
6.8
207.6
Gain or
loss
per cent.
— 1.13
— 9.64
—27.84
+44.68
+56.92
Green
Jowar
38.3
22.7
26.1
5.3
133.6
Bag 7
Silage
31.1
19.7
17.9
6.9
184.2
Gain or
loss
per cent.
—18.80
—13.22
—31.42
+30.19
+37.87
Average
gain or
loss
per cent.
— 9.96
—11.43
—29.63
+37.43
+47.39
TABLE XXIV.
Pit No. 4.—Changes in the total minerals of prime Jowar during ensilage (in gms.).
Rapid filling without watering.
Constituents
P 2 O 5 . . .
CaO .
MgO .
SO 4 .
KCl + NaCl.
.
Green
Jowar
26.1
11.9
16.6
12.9
141.4
Bag 9
Silage
32.4
16.9
20.7
10.1
205.9
Gain or
loss
per cent.
+ 24.14
+ 42.02
+ 24.70
+ 248.27
+ 45.61
Green
Jowar
30.9
16.6
21.5
4.4
114.2
Bag 11
Silage
34.5
16.8
18.2
7.4
208.7
Gain or
loss
per cent.
+ 11.65
+ 1.20
—15.35
+ 68.18
+82.75
Average
gain or
loss
per cent.
+ 17.89
+ 21.61
+ 4.67
+ 158.22
+ 64.18
PROPHYLAXIS AGAINST EQUINE SURRA BY MEANS OF
" BAYER 205 " (NAGANOL).
(A REVIEW OF THE LITERATURE.)
BY
S. K. SEN, M.Sc.,
Assistant Research Officer, Imperial Institute of Veterinary Research, Muktesar.
(Received for publication on 3rd September 1931.)
In considering the prophylactic action of " Bayer 205" (Naganol) against
equine surra, it would be profitable also to discuss at relevant points in the fol-
lowing pages the observations recorded by different workers in regard to the pro-
tective value of the drug for surra of camels and bovines and also for certain
other common forms of animal trypanosomiasis, notably, dourine (due to Trypano-
soma equvperdum) and Mal de Caderas (due to T. equinum), for these observations
provide useful indications which might be well utilized for combating surra of
equities. Moreover, whilst, therapeutically, a drug is liable to exhibit considerable
variation in its capacity to ameliorate the clinical symptoms peculiar to each of
these different forms of animal trypanosomiasis, no such variation need be anti-
cipated in regard to its prophylactic action, inasmuch as, for the same species of
animal, such action is merely a matter of the trypanocidal power of the drug in
respect of the species of parasite concerned, so that, provided the minimum
lethal dose of a drug is approximately the same for these species
of trypanosomes, the same scheme of dosage should be suitable for
adoption for prophylaxis against the disease caused by any one of them. As a
matter of fact, some workers, although experimenting with only one species of
trypanosome, have regarded their findings as being applicable also to other species.
Thus, Hesselbach [1922], in the course of a lengthy discussion upon the trypanoci-
dal action of "Bayer 205 " on T. equiperdum, has stressed the importance of his
findings in relation to surra and sleeping sickness. To present the subject in true
perspective, brief mention is also made of the results recorded by various workers
in regard to the prophylactic action of the drug in small animals.
By way of contrast, it is also proposed to make mention of instances where
" Bayer 205 " has been found almost entirely valueless as a prophylactic against
certain forms of trypanosomiasis, such as T. congolense infection, since, as will be
pointed out later; these instances may provide some possible explanation for any
failure on the part of workers in India to use the drug successfully against cases
apparently due to T. evansi.
( 283 )
284. THE INDIAN JOURNAL OF VETERINARY SCIENCE AND ANIMAL HUSBANDRY [ I, IV
PROPHYLACTIC ACTION OF " BAYER 205 " AGAINST EXPERIMENTAL
TRYPANOSOMIASIS IN ANIMALS.
Perhaps the earliest published records of experimental observations upon the
prophylactic action of "Bayer 205" are those of Mayer and Zeiss [1921], who,
experimenting upon mice, found that the drug remained for several months in the
animal body and during this period it served as a prophylactic against infections
due to T. brucei, T. gambiense, T. equiperdum and T. equinum.
Pfeiler [1922], working with T. equiperdum, found that " Bayer 205 " conferred
protection on small animals which lasted for periods up to 200 days.
Ruppert [1923] found that a dose of 0.4 gramme per kilo. body weight pro-
tected rabbits, for periods up to 6 months, against infections due to T. brucei, T.
equipendum and T. equinum. He also injected 8 horses with increasing doses of
the drug, 3 with 0.25, 2 with 0.5 and 3 with 0.75 gramme per hundredweight
(" pro zentner "), the animals being inoculated with T. equinum after varying
intervals. It was found that a dose of 0.5 gramme was effective for one month,
but that in animals that had received 0.25 gramme, the infection was succesfully
produced after 14 days.
Hesselbach [1922] published the results of a rather remarkable series of ex-
periments upon the prophylactic action of " Bayer 205" against experimental
infection of guinea-pigs with T. equiperdum. Four equal-sized guinea-pigs were
each given a subcutaneous injection of 0.04 gramme of " Bayer 205 " and infected
intraperitoneally with the trypanosomes, 1, 3, 6 and 10 days after the prophylactic
inoculation. None of these animals developed the disease. Hesselbach's findings
are of special interest in that he made laborious observations upon the morpholo-
gical changes undergone by the parasites from hour to hour following upon the
injection of the drug, and for this purpose the trypanosomes that had been injected
into the abdominal cavity (" die in die Bauchhöle gespritzten ") were lifted out
again ("wieder herausgehebert ") by means of a capillary pipette and examined
both in fresh and dry preparations.
Brumpt and Lavier [1923], working with T. equinum, failed to produce the
disease in mice that had been given 5 mg. of " Bayer 205 " 78 days previously.
Schmidt and Oliveira [1924] failed to infect small animals with Mal de Caderas
within a month of the protective inoculation with " Bayer 205 ". These workers
also observed the prophylactic effect of the drug against the same infection in a
mule and a mare which were given 2 and 3 grammes of the drug res-
pectively a fortnight and 6 weeks before inoculation with 10 c.c. of the infective
blood. Neither of these animals developed the infection.
PROPHYLAXIS AGAINST EQUINE SURRA
285
Dios [1925] records an experiment in which a single dose of 4 grammes of
" Bayer 205 " prevented infection in a horse subsequently injected with 70 c.c. of
very virulent blood containing T. equinum. Two dogs were also inoculated with
1.24 grammes and 0.48 gramme of " Bayer 205 " and later infected along with
controls, with the same species of organism (information is not available as to
the intervals between drug injection and infective inoculation). Both the treated
dogs resisted infection while the controls died.
Perhaps one of the most extensive series of experiments yet carried out with
" Bayer 205 " were those by Rodenwaldt and Douwes [1922] upon the efficacy of
the drug for T. evansi infection, although the greater part of their work was carried
out with reference to the therapeutic effect of the drug. An attempt was made to
immunize a horse, weighing 85 kilos, by the simultaneous injection of trypano¬
somes and " Bayer 205 ". The animal subsequently received eight inoculations
with trypanosomes alone during a period of 11 weeks, and it was after the eighth
inoculation that it developed surra and finally died of it.
Baermann [1923] (cited by Edwards, 1928) found that protection lasting for
about 30 to 42 days was conferred on 3 horses injected with 2 to 6 grammes of
" Bayer 205 " and subsequently inoculated, at varying intervals (here again in-
formation is not available as to the duration of these intervals), with surra
parasites.
Kligler and Weitzman [1924] tested the prophylactic effect of various doses
of "Bayer 205" against experimental infection of rabbits and guinea-pigs with
T. evansi. The following protocols are typical of the results obtained by them :—
Rabbit weighing 1390 gms.—Received on 1st July 1923 intraperitoneally 0.10 g.
" Bayer 205 " per kilo. Infective inoculation on 1st August 1923 ; result negative.
One month later another dose of infective blood ; tryps. appeared after 10 days.
Rabbit weighing 1680 gms.—Received intraperitoneally 0.05 g. " Bayer 205 "per
kilo. Infective inoculation after 25 days ; result negative. 63 days later, another
dose of infective blood ; tryps. found after 15 and 18 days.
Rabbit (weight not given).—Infective inoculation 3 days after 0.05 g. " Bayer
205 " per kilo. 12 days after, tryps. appeared in the circulation for one day.
After that, the blood remained negative, although clinical symptoms developed.
5 weeks after the first appearance of tryps., the parasites were again found in the
blood and they persisted intermittently until death of rabbit.
Guinea-pig weighing 440gms. Received 0.2 g. " Bayer 205 " per kilo. intraperi-
toneally. One month later, infective inoculation; tryps. appeared after 15 days.
Guinea-pig weighing 440 gms. Received intraperitoneally 0.3 g. " Bayer
205" per kilo. Infective inoculation after 25 days; tryps. found once
286 THE INDIAN JOURNAL OF VETERINARY SCIENCE AND ANIMAL HUSBANDRY [ I, IV
after 36 days and thereafter the animal was normal. After 88 days the animal
was re-infected a second time; result negative.
In a later paper, Kligler and Weitzman [1925] published the results of a
further series of three experiments with " Bayer 205 ", and these were as follows:—
Rabbit. 0.05 gramme injected. Infected 35 days later; result negative.
Rabbit. 0.05 gramme injected. Infected 35 days later; result negative.
Infected again after 3 months; result positive, after incubation of 15 days.
Rabbit. Injected 0.1 gramme per kilo. Infected one month later; result
negative. Re-infected after another month; result positive, after an incubation of
3 weeks.
Apart from the fact that these observations furnish useful indications as to the
simple prophylactic value of " Bayer 205 ", they have been regarded by Kligler and
Weitzman as being of considerable significance in relation to the question of the
mechanism of the trypanocidal action of the drug (infra).
Edwards [1928], in India, carried out a series of experiments upon the pro-
phylactic effect of " Bayer 205" in horses against experimental infection with
T. evansi. The results have been summarized in a Table which is reproduced
below:—
Animals
Horse20 .
„ 26 .
„ 46 .
„ 46 .
Mare 57
„ 57
.
Horse 28 .
„ 63 .
„ 21 B.
„ 21 B.
Dose in grammes
per 1,000 lb.
body weight
Intravenous
7.5 July 20 .
7.5 July 20 .
5.0 July 23 .
6.0 July 23 .
1.0 Aug. 2 .
1.0 Aug. 2 .
10.0 July 20 .
.....
5.0 July 20 .
5.0 July 20 .
Intrathecal
.....
.....
.....
...
{0.02 Sept. 22
}
0.02 Oct. 22
.
.....
.....
Interval
between
treatment
and
infective
inoculation
22 days .
77 „
.
.
Nil.
74 clays .
Nil.
64 days .
64 „
.
38 „
.
3 „
.
77 ,
.
.
Result
—
+
—
+
—
+
+
+
—
+
PROPHYLAXIS AGAINST EQUINE SURRA
287
The foregoing table shows that while a dose of 7.5 grammes of " Bayer 205 "
per 1,000 lb. body weight protected up to 22 days, a dose of 10 grammes failed to
confer protection for 2 months.
Kasai and Akazawa [1927], in Formosa, record the results of a series of
experiments carried out by them upon the prophylactic action of "Bayer 205"
against a species of trypanosome which they regard as being " in all probability
identical with T. evansi", the disease caused by it affecting water-buffaloes,
zebras, and dogs in that country. In mice, 0.005 gramme of the drug conferred
protection from experimental infection for 5 months. With 0.00003 gramme,
" some of the injected mice were completely protected and others had death delayed
for several days", whereas 0.00001 gramme had almost no prophylactic action,
so that 0.00003 gramme proved to be the minimum dose exercising any protective
power. In calves, subcutaneous injection of 1 gramme per 100 kilo. body weight
protected for a period of 4 months, whereas in horses a dose of 1 gramme per 100
kilo. body weight was not protective " even one month after introduction",
although the duration of the disease was prolonged. Doses of 2 grammes per 100
kilo. body weight, however, protected for 3½ months. (Cf. Bubberman, infra,)
The authors would seem to regard the special virtue of " Bayer 205 " as consisting
in its prophylactic, rather than in its therapeutic properties, and they even consider
the discovery of this drug " as an epoch-making event to open the field of ' chemo-
prophylaxy' as salvarsan to chemotherapy ".
Kleine [1924], however, records having obtained very unsatisfactory results in
regard to the prophylactic action of " Bayer 205", against experimental
infection with Trypanosoma theileri, T. brucei, T. congolense and trypanosomes
of the vivax group, for even a dose of 10 grammes of the drug for a
bullock of about 5 cwt. failed to prevent infection with these trypanosomes.
Certain other workers, too, have recorded their failure to use the drug successfully
against T. congolense or T. vivax infection. Thus, Van Saceghem [1925] succeeded
in setting up infection with these parasites in all of a group of three bovines that
had previously received 5 grammes of " Bayer 205 " per kilo. bodyweight, the
intervals ranging from a fortnight down to simultaneous injection of the drug.
PROPHYLACTIC ACTION OF "BAYER 205" AGAINST NATURAL T
SOMIASIS.
A perusal of the available literature shows that there are remarkably few
observations on record in regard to the prophylactic action of " Bayer 205"
against natural trypanosomiasis of animals. This doubtless, to a large extent, to
be ascribed to the fact that it is barely ten years since the drug was introduced