Molds and Mycotoxins: Effects of mycotoxins
on Swine

Effects of mycotoxins on Swine

Zearalenone

• has estrogenic effect
• levels of 1 ppm (ppm = mg/kg) and greater can cause the following:
  • gilts - enlargement of the uterus, vulva and mammary glands, prolonged heat and poor conception
  • boars (young) - reduced sperm production and libido
  • boars (mature) - no affect
  • sows and gilts - failure to show heat, abortion, stillborn, low fertility, rectal and vaginal prolapses may occur in extreme cases
• can be transferred to piglets through sow's milk, causing enlarged vulvas in female piglets
• does not affect feed intake or growth rate

Vomitoxin (Deoxynivalenol or DON)

•  is a tricothecene
• affects the gastro-intestinal tract
• levels of 1-2 ppm cause a reduction in feed intake and, as a result, rate of gain
• between 0.5 and 3 ppm, it is wise to dilute with clean grain
• as levels increase above 5 ppm, decrease in feed intake may become severe
• levels of 10-20 ppm cause vomiting and complete feed refusal, resulting in reduced body weight gain or body weight loss
• pigs will initially consume sufficient amounts of the ration to induce vomiting, but will voluntarily reduce intake to stop vomiting
• sows are more tolerant than young pigs
• low levels can suppress the immune system

T-2 Toxin

• is a tricothecene
• more potent but less common than vomitoxin
• more likely to be produced during long periods of cool wet weather
• 1 ppm or greater causes vomiting and decreased feed intake, growth rate
• 16-20 ppm causes complete feed refusal

On-farm tests for mycotoxins

 Pigs can be used to test the presence of mycotoxins on the farm.

Zearalenone

• feed 4-6 week old gilts suspect feed for 7-10 days and compare the redness and size of their vulvas with same aged gilts fed clean feed
• slight redness and swelling after 1 week indicates 1 ppm zearalenone
• considerable swelling and redness after 3-4 days indicates 5 ppm or more

Vomitoxin

• feed 4-6 week old piglets (for feeder operations use 35 kg pigs) suspect feed for 1 week
• compare feed intake and growth rate with same aged pigs fed clean feed
• levels of 1-2 ppm vomitoxin cause slight decrease in feed intake and growth rate which may be difficult to detect
• at 3-5 ppm, reduced feed intake will be apparent
• levels of 10 ppm cause dramatic decreases in feed intake, vomiting within 1 day of feeding and slow growth rate

T-2 toxin causes decreases in feed intake at 1 ppm.

 As pigs eating T-2 and vomitoxin respond the same way, you need a lab test to show if one or both are present in your grain or feed.