Mycotoxins and Anti-nutritional factors Flashcards
Are ruminants or non-ruminants more susceptible to the effects of mycotoxins?
Non-ruminants
Which are the most common mycotoxins in farm animals?
Aflatoxins (AF), deoxynivalenol (DON), zearalenone
(ZEN), fumonisins (FUM) and ochratoxin A (OTA)
Which are the main ingredients (plant and animal) that can be affected by mycotoxins?
especially in cereal grains, and are therefore often detected in
animal feeds containing corn, soybean, and wheat, but can also be present in silage, haylage and pasture. Major mycotoxins can also be found in animal-derived products such as eggs, meat, milk and milk by-products
Which factors can contribute to hyporexia in DON?
by direct regulation of anorexigenic pathways in central nervous system after crossing blood-brain barrier in pigs
or indirect peripheral regulations: stimulating secretion of gut-satiety hormones such as peptide YY and cholecystokinin
in pigs.
mycotoxin-induced gut dysbiosis
secretion of inflammatory mediators
What can mycotoxins cause in the affected animal?
Decrease in the food intake
Lower nutrient digestibility
Because of:
Alteration of the intestinal morphology
Increase in activity of pancreatic α-amylase, lipase, trypsin, and chymotrypsin
disrupted glucose uptake
reduction in the microbiome
Which factors play an important role in the animal resistance to mycotoxins?
Localization of animal microbiota in the GIT (ruminants are more resistant to mycotoxins compared to monogastric animals in part because most mycotoxins are transformed to less or non-toxic derivatives by microbes in the rumen)
Species: Poultry species are thought to be less susceptible to DON than swine because microbes in the crop transform DON to its less toxic derivative DOM-1 and deepoxy-DON-3-sulfate (DOM-3-sulfate)
Age: Related to the microbial diversity, in which young animals are more susceptible to infections
differences in mycotoxin metabolizing mechanisms
Antioxidant capacity
GI transit time
Anti-nutritional factors can be heat-stable or heat-labile. Which anti-nutritional factors below are from each group?
- Phytic acid, Condensed Tannins, Alkaloids, Saponins
- lectins, Cynogenic Glycosides, Protease inhibitors, and Toxic amino acids
- heat-stable: Phytic acid, Condensed Tannins, Alkaloids, Saponins
- heat-labile: lectins, Cynogenic Glycosides, Protease inhibitors, and Toxic amino acids
What are the adverse effects of phytates? give examples
Reduce Ca and Fe absorption
What are the adverse effects of oxalates? give examples
Reduce Ca absorption, encourage kidney stone formation
What are the adverse effects of phenol compounds? give examples
They reduce bioavailability of some minerals (especially
zinc). They may negatively affect pH mechanism, reduce
protein digestion.
What are the adverse effects of Lectins (Hemagglutinins)? give examples
Prevent absorption of digestive end products in the small
intestine. They enable the coagulation of red blood cells by affecting erythrocytes.
Lectins are carbohydrate-binding proteins present in most plants, especially seeds like cereals, beans, etc., in tubers like potatoes and also in animals.
What are the adverse effects of protease inhibitors? give examples
They are substances reduce protein digestion.
Most cultivated legumes, such as soybeans
What are the adverse effects of cyanide? give examples
they are respiratory inhibitors. Cyanide causes an increase in blood glucose and lactic acid levels and a decrease in the ATP/ADP ratio indicating a shift from aerobic to anaerobic metabolism
cassava (Manihot esculenta), linseed (Linum usitatissmium),
various sorghums (Sorghum spp.) and white clover (Trifolium repens). Lesser quantities are found in the kernels of such
plants as almonds (Amygdalus communis), apricots (Prunus
armeniaca), peaches (Prunus persica), and apples (Malus
sylvestris)
Which anti-nutritional factor are found in raw soybeans?
Trypsin inhibitors are a unique class of proteins found in raw soybeans that inhibit protease enzymes in the digestive tract by forming indigestible complexes with dietary protein.
Saponins; lectins, oligosaccharides, phytic acid.
What are the adverse effects of saponins? give examples
reduce the bioavailability of nutrients and decrease enzyme activity and it affects protein digestibility by inhibiting various digestive enzymes such as trypsin and chymotrypsin
causing haemolysis in red blood cells. growth impairment and reduce their food intake due to the bitterness
occur in a wide range of plants, including pulses and oil seeds such as kidney bean, chickpea, soybean, groundnut, lupin and
sunflower.
