برنامج رياضى لتقليل التأثيرات الضارة لتلوث البيئة (الهواء) Exercise Program to Delay the Hazardous Effects of Environmental Pollution (Air)

Abstract

Trichothecenes (TCT) are secondary metabolites commonly found in cereals. They are produced in foods and feeds by various species of Fusarium: Myrothecium, Trichothecium, Trichoderma, Cephalosporium, Cylindrocarpon and Stachybotrys. More than 140 different TCT have now been isolated and described. T-2 toxin is the most cytotoxic mycotoxin of the group TCT. It is produced by Fusarium fungi (F. acuminatum, F. poae and F. sporotrichioides) in cereal crops and processed grains. The commonest clinical signs of alimentary toxic aleukia (ATA) caused by T-2 toxin in humans are weakness, vomiting, diarrhea, nausia and abdominal pain. The major toxic effects of T-2 toxin in ruminants include gastroenteritis, hemorrhages, bloody diarrhea and ruminal ulcers. Reduced feed intake and weight gain, diarrhea and impairment of the immune system are the effects caused by T-2 toxin in pigs. Signs of T-2 toxin in poultry comprised decreased feed intake, growth depression, oral lesions, abnormal feathering, decreased egg production, thinner egg shells and impaired hatchability. INTRODUCTION: Trichothecenes: A total number of 148 TCT, (83 nonmacrocyclic and 65 macrocyclic) have been isolated from fungal cultures and plants (Drove, 1988). The TCT are large family of metabolites produced by various species of Fusarium, Myrothecium, Trichothecium, Trichoderma, Cephalosporium, Cylindrocarpon and Stachybotrys (Ueno, 1989; Buck and Cote, 1991). These fungi affect grains in the field, but toxin production in accentuated by storage at cool temperatures; therefore, natural poisoning are most frequent in areas with cooler climates (Jones et al., 1997). Fusarium and Stachybotrys grow at many temperatures but toxin production is highest in cold (< 20ºC) and moist conditions. Trichothecenes are therefore associated with cool climates particularly when grain harvest have been delayed into the winter months, or infected grain has been stored in cold conditions (Jordan et al., 2002). Fusarium fungi are widespread natural producers of TCT and different species have different toxin production profiles. The fungi are commonly occurring soil fungi where they