X-disease

It also became clear that the mold itself - identified by the mold experts (mycologists) as the fairly common species Aspergillus flavus -was not directly responsible for the poisoning. Turkey X disease could be reproduced in the laboratory not only when birds were fed peanut meal contaminated with living mold, but also when fed the same meal after the mold had been killed. 

Turkey X disease, so finding that a mold toxin was involved was no great surprise. But some new surprises were in store. 

DETAILS - Aflatoxins are the poisonous product of a group of polynuclear molds that grow on peanuts, com and in cottonseed meal. They are responsible for the Turkey X" disease which occasionally devastates the poultry industry. The presence of the mold doesn t always indicate presence of the toxin. Toxin production is dependent on various factors such as moisture and temperature. There are two basic types of aflatoxins, both of which are fluorescent under UV (black) light. Once the mold has been identified, the UVI ight is an excellent way to check for toxin production. Aflatoxin B glows blue, while Aflatoxm G glows... 

Little, C.E, The California X-Disease, Amer, Forests, 32 (July 8, 1992). 

Olson C (1969) Bovine hyperkeratosis (X-disease, highly chlorinated naphthalene poisoning), historical review. In Brandly CA, Cornelius CE (eds) Advances in veterinary sciences and comparative medicine. Academic, New York, p 101... 

Aflatoxins are products of species of the genus Aspergillus, particularly A flavus, a common fungus found as a contaminant of grain, maize, peanuts, and so on. First implicated in poultry diseases such as Turkey-X disease, they were subsequently shown to cause cancer in experimental animals and, from epidemiological studies, in humans. Aflatoxin Bl, the most toxic of the aflatoxins, must be activated enzymatically to exert its carcinogenic effect. 

Mycotoxins generally affect the liver (hepatotoxins) or the kidney (nephro-toxins). The problem of mycotoxins in poultry was highlighted in 1960 when more than 100,000 turkey poults in the UK died from what was called Turkey X disease (Blount, 1961). At post-mortem the turkeys were found to be suffering from enteritis with engorged kidneys and /or hepatitis. Bacteriological examinations were negative. The problem was eventually found to be due to aflatoxin contamination in groundnut meal imported from Brazil. 

The need for effective bactericides is greater today than at any time in history. The recognition that mycoplasma-like organisms and xylem-limited bacteria cause plant disease means that there are additional diseases that are amenable to control with antibiotic-like compounds. X-disease, pear decline, peach yellows, phony peach, and plum leaf scorch are a few examples of diseases on deciduous tree-fruit crops caused by phytopathogenic prokaryotes. 

Since the discovery of the Turkey X disease in 1960, aflatoxins have been established as mutagenic, teratogenic and hepatocarcinogenic in experimental animals. AFB] is the most toxic of this group of toxins and the order of toxicity is Bi>Gi>B2>G2. Aflatoxin M] is 10-fold less toxic than Bj, but its presence in milk is of concern in human health [66-68]. AFBj is also one of the most carcinogenic natural compounds known therefore, extensive research has been done on its synthesis, toxicity and biological effects [53, 69-72]. 

Bradbum N, Coker RD, Blimden G The aetiology of Turkey X disease. Phytochemistry 1994 35 817. 

In cattle, PCNs have been associated with X-disease (bovine hyperkeratosis). Other symptoms observed in cattle are vitamin A deficiency, excessive salivation, and thickening of skin followed by loss of hair and occasionally death [1, 262]. Chickens exposed to PCNs showoedema, enlarged fibrous livers and lack of feather pigmentation [263],... 

In 1960-63, the death of turkeys in England (referred to as turkey X disease) was associated with the consumption of peanut meal feeds containing aflatoxins. Death usually occurs from hepatoxicity. Aflatoxin Bj is carcinogenic to a wide variety of animal species rats are particularly sensitive to this effect. It is also mutagenic and teratogenic in rodents. 

Aflatoxins first eame to attention as myeotoxins in the 1960s when many thousands of turkeys and dueks, being fattened for the Christmas market, died. The disease was known as Turkey X disease . It first appeared in turkeys in the summer of 1960 and subsequently over 100000 birds died. The outbreak was eharaeterized by enlarged kidneys and liver lesions. Over 80% of the cases were concentrated within 80-100 miles of London. Investigations showed that the disease was not transmitted between birds but was associated with their feed, all of which had originated from one mill in London. The clue... 

In 1960 more than 100,000 young turkeys on poultry farms in England died in the course of a few months from a mysterious new disease. In view of the lack of an explanation for the disease, it was named "Turkey X disease". Soon, however, it was found that the problem was not limited to hirkeys ducklings and young pheasants were affected, and also showed heavy mortality. 

Intensive investigation of the early outbreaks of the disease indicated that they were aU associated with particular meals given to the birds. On feeding the meal to poults and ducklings, the symptoms of Turkey X disease were rapidly produced. The suspect feed was imported Brazilian peanut meal and initial speculation was that a fungal toxin might be involved. 

Aflatoxins B, Aflatoxins are a closely related group of secondary fungal metabolites shown to be myco-toxins. They are produced by Aspergillus flavus Link ex Fries, the causative principle of turkey "X" disease and by Aspergillus parasiticus Sargeant et at.. Nature 192, 1096... 

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