مرکز منطقه ای اطلاع رساني علوم و فناوري - Place and Importance of Mycotoxins in Dairy Cattle Nutrition

Abstract :

Fungi are filamentous (fuzzy or dusty looking) fungus which have more cellular compounds than yeasts that occur in many feedstuffs; including roughages and concentrates; molds can infect dairy cattle when they are immune suppressed especially during stressful periods. Molds cause a disease referred to as mycosis (Whitlow and Hagler, 2005). Fungi also produce poisons called mycotoxins that affect animals when they consume mycotoxin contaminated feeds. This disorder is called mycotoxicosis (Whitlow and Hagler, 2005). It has been estimated that 25% of the world’s crops are affected by mould or fungal growth. These fungal toxins range in molecular weight from ca. 200 to 500 (Whitlow and Hagler, 2013). The complex diet of ruminants, consisting of forages, concentrates, and preserved feeds, can be a source of very diverse mycotoxins that contaminate individual feed components. A number of mycotoxins are successfully inactivated by the rumen flora, whereas others pass unchanged or are converted into metabolites that retain biological activity. Thus, the barrier function of the rumen largely determines the susceptibility of dairy cows and other ruminant species towards individual mycotoxins (Fink-Gremmels, 2008). Usually, exposure is through consumption of contaminated feedstuffs or foods. Mycotoxicoses are diseases caused by exposure to foods or feeds contaminated with mycotoxins (Nelson et al.,1993). Mycotoxins exhibit a variety of biological effects in animals such as: liver and kidney toxicity, central nervous system abnormalities, estrogenic responses and others (Whitlow and Hagler, 2013).