Kobert also refers to the toxic nature of the so-called sleepy grass (" Stipa vaseyi "), and suggests that its toxicity is due to a parasitic fungus. However, Marah and Clawson (1929) proved that this plant is poisonous to horses and sheep and make no mention of the presence of fungi on the plant. As active principles he describes conutin (or secacornutin), which causes contraction of the uterus; sphazelinir.
Lander (1926) refers to the toxicity of ergot and darnel, but does not mention that the toxicity of the latter is due to a fungus. The symptoms di~:> appear within a few days after cessation of feeding with "Diplodia zeae". Danckwortt also found no difference of any significance in the content of hydrogen sulphide in American barley and normal barley.
Heller, Caskey and Penquite (1930) suffered adverse effects from inhaling the smut spores during their investigations into the toxicity of smut. At autopsy, pronounced hyperemia of the small intestine and edema of the lungs were present. Csukas (1932) describes cases of acute inflammation of the upper respiratory tract in horses and in some of the people attending these horses.
Dickson and his co-publishers (1930) found that the active substances of the above harmful moldy American barley are associated with those fractions of the extracts which contain glucoside or basic nitrogenous compounds.
ONDERSTEPOORT EXPERIMEN 1 1'S
The skin of the mold was separated from the juice, washed several times in the tapwa.ter, and then given to this animal. The mold skin was separated from the liquid, washed several times in tap water, and then given to this animal Rabbit M. I For stomach tube I Liquid from which the wet "mold skin" had been removed in rabbits K and L , was given. to this rabbit Rabbit N.
The "mold skin" was separated from the liquid, repeatedly washed in tap water and soaked until this rabbit (No. 632). was given~ to this animal Fnsarium ~oniliforme v~~-subglutina~~ cult.ures on Raulin's medium. The fluid, from which the "mold skin" soaked to mbbit Aq was removed, was given to this rabbit FusaTium nwniliforme Sb. The "mold skin," as treated above, was given to this rabbit (No. 602). The liquid, from which the "mould skin" impregnated with rabbit ax was removed, was given to this mhbit Mealie flour infected with FusaTium monilifonne var. .
Fed (did not give additional food 145 days Fusarium monilifarme var. subg~u~nans) culture on corn (no. 602) Rabbit Bz. Mushrooms. See Leemann's article on darnel in this Journal.) 45-day culture of Fusa1·iU1n monilifonne Sh. dependent subglutinans Wr. and Rkg.). 48-day culture of Fusarium grmninea1·um Sahwabe on (barley grain) corn (No. 630) 42-day culture of Fusarinm gramine.arum Schwabe on barley grain (No. 630).
Twelve rabbits and one pig received cultures of this fungus grown on corn without suffering any ill effects; cultures were grown for different periods and at different temperatures. A pig has ingested 2400 grams of a 45-day culture of this fungus on barley grain without suffering any harmful effects; (d) four rabbits received cultures of Fusarium graminea1"Um Schwabe in Raulin's medium without showing any symptoms of poisoning; one rabbit and one pig received this fungus grown on corn, and one pig a culture of it grown on barley without any effect noxious; and (e) two rabbits, a pig, and a dog, received large quantities of the infected fungus Lolium temulentum Linn (drabok) (see Leemann's article on this plant appearing elsewhere in this journal) without suffering any effect harmful.
DISCUSSION
The fact that Diplodia zeae, which Mitchell and Theiler have shown to be toxic, is often found infesting flours, especially those grown in high-rainfall areas, calls for special care in using corn infected with the fungus for domestic and domestic purposes. feed for stock. In addition to these symptoms, rust spores and soot, if inhaled in large quantities, can cause severe irritation of the mucous membranes. They are recorded as: ga;;tro-enteritis with bleeding and erosions, accumulation of serum in the brain tissues and in the arachnoid sac, hyperemia and edema of the brain and spinal cord, hemorrhagic fluid in the peritoneal cavity, cystitis, nephritis, peritonitis, acute yellow atrophy live1, bronchitis , bleeding in the serous membranes, swelling of the spleen, cloudy swelling of the liver, kidneys and myocardium, as well as necrosis and mummification of the extreme parts of the body.
Theoretically, there are two ways in which fungi can make the substrate toxic, namely (c) by forming poison in their mycelia and spores and retaining it in their own structures, or by secreting it into the substrate, or (b) by causing the formation of toxins. toxic substances due to the breakdown of one or more components of the subsurface. The following factors can and probably are involved in determining the toxicity of mold-infected foods. Furthermore, with regard to the production of oxalic acid in fungal cultures, it turned out that the origin of the nitrogen present in the media was of great importance.
In Rome, individual susceptibility can be explained by an impaired function of the liver; and kidneys; (cirrhosis, degeneration) and an inflammatory condition in the gastrointestinal tract at the time of poisoning. 9) In connection with the above possibilities, which may explain the conflicting information regarding moldy food poisoning, I would like to mention that the different invr-stigators, due to wrong identifications, may not have worked with the same kind of fungus in the ~pite of the father! In the studies of the toxic components in moldy foods and artificial cultures of molds, attention has been paid almost exclusively to the products from the breakdown of the proteins in the substrate. The three substances present in the substrate that are most likely to be attacked by the fungi are starch, proteins and fats.
It seems quite possible that non-toxic or very slightly toxic substances will be produced in the decomposition of fats, since in the presence of starch and protein they will doubtless be attacked very little by most fungi. Moldy foods that are high in protein and low in starch will have the potential to form toxic biogenic amines as protein breakdown products. There appears to be considerable variation in the susceptibility of different classes of animals to the effects of moldy foods.
It therefore seems impossible to lay down a general rule as to the relative susceptibility of different classes of animals to foods contaminated with fungi. From the preceding discussion it appears that as a general rule care should be taken in feeding moldy foods to horses and pigs, while ruminants and chickens appear to be less susceptible. The opposite is true for maize infected with Diplodia zeae. l).
ACKNOWLEDGMENTS
LITERATURE
Effects caused by feeding cattle with l'aspalmn d·ilatatu•n infected with the species E1·got Claviceps pa.spali.
