INTRODUCTION
CLAUDIA CAFARCHIA
Department of Veterinary Public Health, University of Bari, Valenzano (Bari), Italy
Mycotoxicoses are acute or chronic intoxications caused by mycotoxins produced by moulds (fungi) that contaminate plant materials.
More than 100 fungal species are known to produce mycotoxins. Many of these fungi belong to the genera Aspergillus, Penicillium and Fusarium. The growth of the fungi and the production of toxins occur in the presence of a suitable substrate (mainly starch), moisture (water activity = 0.90) and temperature (from 4 to 31°C, depending on the type of mycotoxin).
Examples of mycotoxins of great significance for both public health and agro-economic perspectives include aflatoxins, ochratoxins, trichothecenes, zearalenone, fumonisins, patulin and ergot alkaloids. Feedstuffs most frequently contaminated with mycotoxins include nuts, oilseeds and grains.
Some species of fungi can produce several mycotoxins, which may differ in their biological activities, resulting in complex clinical effects. The severity of the clinical signs depends upon the length of exposure to the contaminated feed and the quantity of mycotoxins ingested.
The diagnosis may prove challenging because the clinical signs are often similar to those caused by other agents or pathogens. Presently, the European Community has imposed limits or guidance levels for several mycotoxins in human food and feed for domesticated animals(1). Conversely, no limits are indicated in the case of feed for wild animals, thus allowing contaminated grain to be fed to wildlife.
However wildlife should not be fed, or should be prevented having access to, grain with levels of mycotoxins exceeding those recommended for use in domestic animal food. When non-specific signs of ill health are seen in wildlife (both mammals and birds) epidemiologically associated with arable fields or consuming grain, the possibility of mycotoxicosis should be considered, even though reported cases of toxicosis in European wild species are rare.
Wherever possible, grain derived from fields in which wildlife is present should be carefully checked for mycotoxins by specialized laboratories. In cases of heavily contaminated fields, deep ploughing can effectively remove the grain from access by most wildlife species.Handling mycotoxin-poisoned ill or dead animals does not present a risk for human health. However, meat or
Infectious Diseases of Wild Mammals and Birds in Europe, First Edition. Edited by Dolores Gavier-Widen, J. Paul Duff, and Anna Meredith. © 2012 Blackwell Publishing Ltd. Published 2012 by Blackwell Publishing Ltd.
TABLE 42.1 Mycotoxins and toxicity in animals.
| Mycotoxins | Fungal spp. | Animal spp. affected | Toxicity | Limits for total mycotoxins in food and feed |
| Ergot alkaloids | Claviceps purpurea | Cattle, sheep, deer, horses, pigs, poultry | Neurotoxicity, vasoconstriction | 0.1% (feed with cereals — European Directive 2002/32/EC) |
| Ochratoxins A, B, C | Aspergillus ochraceus, Penicillium viridicatum | Pigs and poultry | Degenerative renal changes, fall in egg production | From 3 to 50 ^Sg/kg (cereals and cereal products) |
| Patulin | Penicillium expansum | Laboratory animals | Teratogenic effects in chicken embryos, exophthalmia | From 10 to 50 μgZkg (baby food and fruit products) |
| Satratoxin, roridin, verrucarin | Stachybotrys atra | Horses, cattle, sheep, pigs | Cytotoxicity, coagulopathy, immunosoppression | NR |
| Sterigmatocystin | Aspergillus nidulans, Aspergillus versicolor | Rodents, cattle, monkeys, fish | Carcinogenicity, mutagenicity, teratogenicity | NR |
NR — not reported
products from animals known to have died of mycotoxi- cosis should not be consumed.
Until now, intoxications by only two types of mycotoxi- cosis (aflatoxicosis and fusariotoxicosis) have been reported in free-ranging animals (wild birds).
Although there are reports of mycotoxin detection in food and feed in many European countries (Germany, France, Italy, Greece, Belgium) the occurrence of cases of poisoning in European wild animals appears to be rare or unreported.
In this chapter aflatoxicosis and fusariotoxicosis are described; see Table 42.1 for the toxicity associated with other relevant mycotoxins.