152. Groundnut poisoning

NATURAL PRODUCTS water, methanol, ethanol and acetic acid; this was particularly noticeable in the presence of oxygen. Chromatography of the irradiated toxin revealed several fluorescent spots in place of the original single spot. During the determination of FBi's physical properties, ultraviolet absorption and mass spectrometry studies had demonstrated the presence of impurities in the crystalline material. Zijden, A. S. M. B., Koelensmid, W. A. A. van der., Boldingh, J., Barrett, C. B., Ord, W. O. & Philp, J. (1962). Aspergillus flavus and turkey X disease. Isolation in crystalline form of a toxin responsible for turkey X disease. Nature, Lond. 195, 1060. 150. PURIFICATION AND CHARACTERIZATION OF AFLATOXIN The authors report that aflatoxin which had hitherto appeared to be a chromatographically homogenous material has been resolved by thinlayer chromatography into 2 fluorescent components, respectively Aflatoxins B and G. Aflatoxin B fluoresces blue-violet in ultraviolet light, softens at 250-260 °, melts at 270 ° and has a molecular formula of CxTH1206. Recently, however, evidence had been obtained that this component consists of 2 closely similar substances. Aflatoxin G exhibits a green ftuoescence in ultraviolet light, melts at 247-250 ° and has a molecular formula C17H1207. Aflatoxin B appears more acutely toxic than Aflatoxin G; in l-day-old ducklings the LDso values were respectively 20 and 60 ~lg. Nesbitt, B. F., O'Kelly, J., Sargeant, K. & Sheridan, A. (1962). Aspergillus flavus and turkey disease. Toxic metabolites of Aspergillus flavus. Nature, Lond. 195, 1062. 151. TOXICITY OF ASPERGILLUS FLAVUS EXTRACTS In this report the plot is thickened by the finding that when grown upon a glucose-ammonium nitrate medium Aspergillus flavus synthesized at least 12 fluorescent components, of which 5 gave rise to liver damage in ducklings. Separation upon thin layers of Kieselgel G was achieved of the materials present in a chloroform extract of a 9-day culture of Aspergillus flavus. All but 3 of the fractions were isolated by removing the relevant band of adsorbent, extracting with chloroform and rechromatographing until substantially homogenous fractions were obtained. Each fraction was administered by mouth to separate groups of ducklings in 5 daily consecutive doses. Liver damage similar to that produced in Turkey X disease followed the ingestion of 5 of the 9 fractions tested. Less toxic strains of Aspergillus flavus appeared to produce less complex mixtures of fluorescent components than did the highly toxic strains. Smith, R. H. & McKernan, W. (1962). Hepatotoxic action of chromatographically separated fractions of Aspergillus flavus extracts. Nature, Lond. 195, 1301.

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152. G R O U N D N U T POISONING Isolated cases of groundnut poisoning in animals continue to occur despite the application of measures to prevent it. Earlier this year. an outbreak was reported in pigs (Hornby et al., Vet. Rec. 196.2, 74, 52 & 189) which had received rations containing 3 ~o of groundnut meal partly made up of an Indian meal which was subsequently found to have caused many deaths in pigs and calves throughout the Midlands. A further outbreak in cattle has now occurred caused this time by a toxic sample of Brazilian groundnut meal. Sixteen steers and heifers were fed a diet containing the groundnut meal for 4~ months. Of these 5 had to be slaughtered on account of their poor condition. The remainder were placed on excellent pasture and were no longer given groundnut meal. Biopsies on the livers of 4 of the surviving animals showed them to be pale in colour and fibrotic. When the animals were sent for slaughter 4-6 months after withdrawal of the toxic meal they had made very little growth, although their condition showed a fair improvement. A sample of the suspected meal proved toxic to ducklings. Liver damage characteristic of groundnut poisoning was observed at post mortem. Clegg, F. G. & Bryson, H. (1962). An outbreak of poisoning in store cattle attributed to Brazilian groundnut meal. Vet. Rec. 74, 992. 153. AFLATOXIN IN MAIZE In a letter to the Editor of Vet. Rec. the authors mention inter alia that they have detected the presence of aflatoxin in 2 samples of maize sent them for examination by a veterinarian in an unnamed tropical country. No further details were given. [While aflatoxin has been shown to be formed when cultures of Aspergillusflavus were intentionally grown upon runner bean seed, cottonseed, wheat and poultry food, this report is the first describing aflatoxin synthesis in a natural foodstuff, other than groundnuts, during cultivation.] Carnaghan, R. B. A. & Allcroft, Ruth (1962). Groundnut toxicity. Vet. Rec. 74, 925. 154. F U N G A L TOXINS AND ANIMAL DISEASE In an Editorial the Vet. Rec. draws attention to the seriousness of the diseases that were known to be due to fungal toxins (mycotoxicoses), and suggests other diseases which may prove to be of fungal origin. Very serious outbreaks of a seasonal disease in farm horses in Russia from 1930 onwards were caused by a toxic substance formed by certain strains of a fungus, Stachybotrys atra, present in mouldy hay or straw. In New Zealand, major losses were suffered by sheepfarmers as a result of facial eczema, a disease in which the affected sheep suffered severe liver damage. This condition arose from the action of a product synthesized by a fungus which was found in certain ryegrass pastures. Lastly,