46 



CyANOGENEiSIS in SoKLillUM VULGAKE 



Hydrocyanic 

 acid in dura 



.Sennar 



Albara 



Reports on 



poisonous 



dura 



Gezira 



Reverting to tlie sulyect nf (lura, inentioii must be made of auothiT matter 

 relatiiiji!; to it which has chiimed atteutioii. This is the ])reseiice of hydrocyaiiie acid 

 in (hini used as fodder, and tlie fataUty resulting amongst animals fed on sueli dura. 

 Attention was directed to the subject by reading accounts of the discovery by 

 Dunstan and Henry' of a glucoside, "dhurriu," contaiued in tlie young plants 

 of the sdrghnm, which on decom])ositiou in the presence of water yields free 

 hydrocyanic acid. THis is said to explain the numerous cases of sudden death 

 occurring among cattle fed on immature sorghum. The anah'tical work of 

 Briinnich - on the same subject, and the obser\ations of Dr. Maxwell, and 

 Veterinary-Inspector Quinnel ' in Australia, shoAv how important it is, and accord- 

 ingly, through the medium of the Secretary General one collected as much 

 inforjnation as could be gathei'cd from xarious parts of the Sudan, and proceeded 

 to examine some specimens of dura in which no difficulty was experienced in 

 detecting the poisonous acid. The answers to the enquiries are interesting, and may 

 \vith advantage be briefly stated here. 



Colonel Gorringe reported from Sennar that there had been no recent casualties 

 among animals from this cause, but recalled a considerable loss in horses and cattle 

 at Kerreri in 1898, from their having been fed on green dura about one foot high. 

 He states that the natives in his district regard it as harmless Avhen dry, and do not 

 give it when green till the seed ears are Avell developed. I\Ir. Xeville, from the 

 Atljara district, furnished much important information, and recorded his opinion 

 that dura oi normal gro^vth is alisolutelv innocuous to animals in the Sudan. He 

 also stated that the variety known as Peterita is the most poisonous, and that more 

 deaths result from animals eating " hantout " and other poisonous gi-asses tliau from 

 dura. The most fatal t'ondition, he says, and the most common in the Sudan, 

 is produced when aninials are fed on dura which has been stunted from lack of 

 rainfall and has then grown rapidly when water was obtainable. Natives, he fiu-ther 

 states, are well aware of the danger, and belie\e that onlv ruminants suffer and that 

 donkeys and horses may feed on such dura with impunity. Colonel Stanton, 

 hoAvever, infoi*med me that on one occasion his horse, although well and hungry, and 

 though he expected it to feed greedily on some tempting green dura, i-efused to 

 touch it. Possibly animals of a higher intelligence than cattle may recognise and 

 avoid the danger. Mr. Xe\ille also enters into a consideration of other ill-effects 

 produced by dura such as colic and kidney troubles, due to the jjresence of large 

 (juantities of potassium nitrate in the plants. 



Major Dickinson. Gezira, gave evidence which coini-ides with that of Mr. 

 Xeville, and mentioned fatal cases occurring at Wad Kamleli in 1902. Some 



' Phil. Trans. 1901 Scries, B 515, and 1902 Series, A 399 'Journ.il Chemiciil Society, July, 1903 



' Injurious effect of sorghum on stock. P.aper Agric. Con., liuecnsland, June, 1902 



