The influence of mycotoxins on animal production is related to food consumption rejection, decreased protein synthesis, and reduced growth and feed conversion loss. The mechanism of action is related to their chemical structure and the animals’ ability to detect their presence in food.

We will examine each of these three aspects:

• Food rejection

The avian brainstem has poorly developed olfactory and gustatory ganglia, while porcine livestock has highly developed ones. Consequently, food rejection is more frequent in the latter one, especially in the presence of sesquiterpene toxins. Food rejection has been reported due to the presence of T-2 toxin in pig feed from 4500 µg/kg, diacetoxyscirpenol in pig feed from 2500 µg/kg, and deoxynivalenol in pig feed from 300 µg/kg. A 34.5% decrease in pig feed intake has also been reported with the ingestion of 4000 µg/kg. Birds do not show a decrease in consumption, making the presence of mycotoxins more dangerous as their intake continues at the same levels.

• Decreased protein synthesis and consequent decreased immunity

Essentially, this is due to the presence of hepatotoxins, which affect protein synthesis, and necrotizing toxins of the digestive mucus that reduce protein absorption. These effects have been reported due to the presence of aflatoxin B1 in bird feed from 250 µg/kg, resulting in decreased resistance to P. multocida and E. tenella, and in pig feed from 400 µg/kg, resulting in decreased resistance to S. enteritidis. Additionally, the presence of Ochratoxin A in bird feed from 500 µg/kg increases the incidence of necrotic enteritis by C. perfringens and in pig feed from 2,500 µg/kg decreases the response to vaccines against A. pleuropneumoniae. Finally, the presence of Toxin T-2 in bird feed from 500 µg/kg increases coccidiosis by E. tenella and in piglet feed from 500 µg/kg causes enteropathy by Lawsonia intestinalis.

• Decreased growth and feed conversion loss

This is also due to the presence of hepatotoxins which affect protein synthesis, and of necrotizing toxins of the digestive mucus that reduce nutrient absorption. These effects have been reported due to the presence of mycotoxins of the coumarin group (aflatoxins, sterigmatocystin), resulting in a 20% growth delay in broilers with the ingestion of 4500 µg aflatoxin B1/kg for 15 days and a 31.7% growth decrease in pigs  with the ingestion of 7500 µg Aflatoxin B1/kg for 40 days. Mycotoxins of the laconic group (ochratoxin) produce a 26.9% increase in feed conversion (8000 µg ochratoxin A/kg for 20 days). Mycotoxins of the fumonisin group result in a 6.7% growth decrease in pigs with the ingestion of 100 µg Fumonisin B1/kg for 30 days and an 8% decrease in pig growth with the ingestion of 1000 µg Fumonisin B1/kg for 35 days. Finally, it has been reported that mycotoxins of the sesquiterpene group (T-2, Vomitoxins) cause a 26.2% growth decrease in pigs with the ingestion of 1000 µg Deoxynivalenol/kg for 40 days and a 41.94% decrease with the ingestion of 5000 µg Deoxynivalenol/kg for 20 days.