ANN 111: Principles of Animal Nutrition and Feed Technology (2+1)

CYANOGENS

Sorghum and sudan grass, linseed  and cassava root contains relatively high levels of Cyanide. These plants generally contain cyanogenetic glycoside, which is hydrolysed to hydrocyanic acid (HCN) by the enzyme usually present in the same plant.  High level of HCN is found in the new growth that follows either a period of drought, or a period of heavy trampling or physical damage by frost etc.  Heavy nitrate fertilisation of the soil followed by an abundant irrigation or rainfall may increase the HCN poisoning potential of these crops. However under favourable condition these plants do not produce HCN toxicity. Excess cyanide ion can quickly produce anoxia of the central nervous system through inactivating the cytochrome oxidase system, and death can result within a few seconds.  Based on the intensity, animals show nervousness, abnormal breathing, trembling or jerking muscles, blue colouration of the lining of the mouth, spasms or convulsions and respiratory failure. Treatment includes intravenous injection of sodium nitrate and sodium thiosulphate. Ruminants are more susceptible to HCN poisoning than are horses and pigs, because the gastric HCl in monogastric animals destroys the enzyme concerned in the release of HCN.

High level of HCN is found in the new growth that follows either a period of drought, or a period of heavy trampling or physical damage by frost; heavy fertilisation followed by abundant irrigation. Cyanide can quickly produce anoxia of the central nervous system and death can result within a few seconds. Ruminants are more susceptible to HCN poisoning than are horses and pigs.