Show simple item record Botha, C.J. (Christoffel Jacobus) Venter, Elna
dc.contributor.other University of Pretoria. Faculty of Veterinary Science. Dept. of Paraclinical Sciences. Section Pharmacology and Toxicology
dc.coverage.spatial Africa en
dc.coverage.spatial South Africa en 2008-12-22T08:55:24Z 2008-12-22T08:55:24Z 2002
dc.description Colour photos. Final web-ready size: JPEG, 72 ppi. Photo 1: 35.9 kb; Photo 2: 27.6 kb; Photo 3: 21.6 kb, Photo 4: 9.9 kb. Original TIFF file housed at the Dept. of Paraclinical Sciences, Section Pharmacology and Toxicology, University of Pretoria. en
dc.description.abstract DISTRIBUTION: Annuals, ephemeral growth (“opslag”) or perennials. Often cultivated in gardens. en
dc.description.abstract BOTANICAL DESCRIPTION: Typical daisy flower, ray florets on the outside. Often scalloped leaf. Sticky, sometimes aromatic. en
dc.description.abstract TOXIC PRINCIPLE: • Cyanogenic glycosides • LD HCN + 2mg/kg in all species • Monogastric animals less affected by plants with cyanogenic glycosides because HCl destroys hydrolysing enzymes • Plants with more than 20mg % (200 ppm) HCN, potentially dangerous. en
dc.description.abstract ABSORPTION AND DISPOSITION: • CN¯ rapidly absorbed from g.i.t. and by inhalation (HCN gas)• Rapidly and very effectively detoxified in body by sulphur transferase (rhodanese) enzymes which bind it to sulphur from sulphane pool forming thiocyanate (which is excreted through urine). • Possible to ingest just less than LD continuously over extended periods without harm. • If rate of liberation from glycosides in plants exceeds speed of detoxification, problems occur. en
dc.description.abstract MECHANISM OF ACTION: • In excess situation CN¯ binds stably with Fe³+ in tissue cytochrome oxidase system and inhibits this. Thus electron transport and oxidative phosphorylation is stopped and chain of cellular respiration is halted. • Results in histotoxic anoxia or hypoxia. • Normal oxygenation of blood not interfered with. • Blood stays red. (When treating, jugular blood much redder than normal.) • CNS depression sets in (oxygen requirement of CNS high) • Terminally respiratory depression sets in and available oxygen is utilised by uninhibited cytochrome oxidase leading to cyanosis. en
dc.description.abstract SYNDROMES: Prussic acid poisoning, geilsiekte. en
dc.description.abstract SYSTEMS AFFECTED: Haemopoietic system. en
dc.description.abstract CLINICAL SIGNS: In practice a problem in cattle, sheep and goats. Peracute: • Death in few minutes - usually found dead. • Transient convulsions progressing to paralysis, stupor. Acute: (usually) • Respiratory distress - dyspnoea (gasping), polypnoea, cyanosis. • CNS excitement and tremor - convulsions, paralysis and stupor. • G.I.T.: Bloat, frothing at mouth and salivation may occur. en
dc.description.abstract NECROPSY: • Cyanosis - (in peracute poisoning e.g. execution in man, may have bright red blood). • Congestion of blood vessels (blood unclotted or clots slowly). • Asphyxiation signs: haemorrhages in trachea, bronchi and lungs. • Subepi- and -endocardial haemorrhages frequent. • Smell of bitter almonds (only some individuals can smell it) • Rumen: Leaves and other plant residues. en
dc.description.abstract DIAGNOSIS: • HCN rapidly degraded and dissipates easily. • Specimens to be taken soon after death. • Degradation rapid in liver and rumen. • Much slower in muscle, although HCN concentration in muscle is much lower. With long interim this is the specimen/organ of choice. Still positive next day. 1. PM as soon as possible 2. Keep specimen refrigerated or frozen: • Ruminal content • Liver • Muscle • Plant material. en
dc.description.abstract TREATMENT: Two steps: 1. Remove the cyanide from the cytochrome oxidase and fix this lethal CN¯ in harmless, inert form. CN has greater affinity for tissue cytochrome oxidase Fe3+ than methaemoglobin, but can be removed from cytochrome system by large methaemoglobin concentrations. Therefore increase methaemoglobin concentration carefully and under controlled conditions with NaNO2 solution intravenously. 2. Then assist in removal of CN¯ via urine as thiocyanate. Assist sulphur transferases to inactivate cyanide by supplying sulphur in form of sodium thiosulphate (“hypo”). en
dc.description.abstract PREVENTION AND AVOIDANCE: Supply extra sulphur • 5-7% flowers of sulphur in lick • Hypo in drinking water Avoid or limit grazing of plants during danger periods - avoid wilted, frosted and hail-damaged material. en
dc.description.uri en
dc.identifier.citation Botha, CJ & Venter, E 2002, 'Plants poisonous to livestock Southern Africa (CD-ROM)' University of Pretoria, Faculty of Veterinary Science, Dept. of Paraclinical Sciences, Section Pharmacology and Toxicology, Pretoria, South Africa. en
dc.rights ©University of Pretoria. Dept. of Paraclinical Sciences, Section Pharmacology and Toxicology (Original and digital). Provided for educational purposes only. It may not be downloaded, reproduced or distributed in any format without written permission of the original copyright holder. Any attempt to circumvent the access controls placed on this file is a violation of copyright laws and is subject to criminal prosecution. Please contact the collection administrator for copyright issues. en
dc.source Original format: University of Pretoria, Faculty of Veterinary Science. en
dc.subject Plant poisoning en
dc.subject Toxicology en
dc.subject Plant poisoning in animals en
dc.subject Poisonous plants en
dc.subject Prussic acid en
dc.subject Geilsiekte en
dc.subject HCN en
dc.subject Glycosides en
dc.subject.lcsh Poisonous plants -- Toxicology -- Africa, Southern en
dc.subject.lcsh Veterinary toxicology en
dc.title Asteraceae en
dc.title.alternative Daisies en
dc.title.alternative Gousblomme af
dc.title.alternative Castalis spectabilis en
dc.title.alternative Dimorphotheca sinuata en
dc.type Still Image en

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