102
Studies on the Curing of Poisonous Jawar Pers
Table I reveals several points of interest. It may be seen that the amount of prussic acid present
in the stem was comparatively more than that of leaf. Similar results were obtained on examining
12 samples from the same affected area. Bagchi and Ganguly [1941] also found stems of 16 to 36
inches long plants richer in hydrocyanic acid than the leaves. Acharya [1933], however, stated
that the leaves contained more hydrocyanic acid. On drying the plant, at room temperature about
70 per cent of the prussic acid was lost after 24 hours, and 75 per cent after 48 hours. When drying
was continued for five days in shade at room temperature (27° to 30°C.) the loss in the prussic acid
content was 77 per cent. The plant could not be made absolutely free of prussic acid even on drying
in shade for 15 days. Acharya (loc cit) also found that drying in shade had little effect on the prussic
acid content. Swanson [1921], however, stated that the shade dried sorghum contained only traces
of prussic acid.
A remarkable loss of prussic acid was observed when the plant was dried in the sun even for
short periods. Eight hours drying reduced the prussic acid by 90 per cent. Seven days drying
under field conditions rendered the plant absolutely free from prussic acid. Leather [1906] found
that sun-drying did not decrease the amount of cyanogenetic glucoside and Acharya (loc cit) stated
that sun-drying reduced the amount of prussic acid appreciably. Chopra and Badhwar [1940] also
assume that the well dried plants are not dangerous. This procedure of drying in the sun and leaving
the plants out in the open at night was repeated thrice with the same results. The whole area under
jawar crop was cured like this and fed to cattle without any untoward effects.
An alternative method of curing was also tried by ensiling the affected plants. The fresh plants
were cut into two and ensiled in two small experimental pits of 4 ft. × 4 ft. × 4 ft. Locally grown
hay consisting mostly of Saccharum spontaneum (kans) was used as cover. Samples from one pit
were examined after every 10 days for prussic acid. It may be seen from Table II that the plants
ensiled for about a month lost the entire prussic acid content. It is likely that the increased acidity
and temperature in ensiling liberates the prussic acid from its combination with the enzyme and
it is subsequently decomposed.
TABLE II
Hydrocyanic acid in ensiled samples of jawar
On dry basis
Particulars
Pit No. I
Pit No. .11 .
Fresh sample
.
.
.
.
.
.
.
.
10 clays ensiling . . . . . . . .
{20 days ensiling . . . . . . . .
30 days ensiling . . . . . . . .
Two
months ensiling . . . . . . . .
mg. of HCN per 100 gm.
14.9
5.2
1.0
nil
nil
The ensiled sorghum from the second pit opened after two months was fed to three bullocks for
a period of 30 days with no harmful effects. The animals relished the succulent fodder.
Although there is no experimental evidence, Van Der Walt [1944] has drawn attention to a
condition of chronic prussic acid-poisoning if improperly cured sorghum is fed over a prolonged
period. Similar views have been expressed in the U.S.A. Veterinary Science News Letter [1944]
that small amounts of cyanogenetic forage is capable of causing demyelination if repeatedly consumed.
SUMMARY
Attempt has been made to utilize poisonous jawar as fodder by different treatments. It has
been found that drying the affected plants in the sun for seven days or ensiling for 30 days renders
the plant free from prussic acid.