Animal feed samples tested for mycotoxins

13-06-2016 | |
[Photo: Natalia Klenova]
[Photo: Natalia Klenova]

Analysis of 1740 raw material and animal feed samples showed widely divergent contamination profiles in corn and wheat.

The survey, carried out by the company Pancosma evaluated the risk posed to livestock animals by 46 different mycotoxins, mainly in Europe.

Poultry feed: high risk of trichothecenes type A contamination

In 2015, poultry feed was found to be particularly contaminated with both type A and B trichothecenes. Although type B trichothecenes are less harmful for poultry than pigs, as poultry are better equipped to metabolise them, they were found to be present above 300 ppb in 61.3% of poultry feed samples tested, which could explain their reduced growth performance. The threshold level beyond which layers and breeders succumb to type B trichothecenes is 300 ppb. But the main concern was type A trichothecenes, which was found in almost 1 out of every 5 samples at levels above 20 ppb, the sensitivity threshold for this type of mycotoxin in layers and breeders. These mycotoxins are highly toxic for poultry and can affect feed intake and body weight. These effects could have been exacerbated by the presence of tenuazonic acids, which was found to be present at levels above 100ppb in 42% of the samples.

Zearalenone was detected in 41% of the samples at concentrations above 50 ppb, which could have impacted fertility and hatchability, in addition to decreasing the sensitivity threshold by creating synergistic toxic effects in cases of multi-mycotoxin contaminations. Ochratoxins, which are known to have a negative effect on hatchability, were not of concern this year, except in some very specific cases. The multi-mycotoxin contamination of the large majority of the poultry feed samples was alarming.

Swine feed: nearly 100% mycotoxin contamination

In the 2015 survey, mycotoxins were in all except one of the swine feed samples tested, and moreover, 93% of these samples showed multi-mycotoxin contamination, raising the level of risk. Type B trichothecenes were of particular concern in swine feed samples, which could explain decreased growth performance. Of all the samples tested, 58% were contaminated at levels above 200 ppb. These effects on performance may have been exacerbated by the presence of tenuazonic acids, that were also detected in swine feed.

Zearalenone was found in at least 1 out of 5 swine feed samples, with the potential to affect fertility, resulting in reduced litter sizes, and enlarged vulvas. As zearalenone is transferred into the milk, piglets may also have enlarged vulvas.

Silages: zearalenone and type B trichothecenes of concern

In the 2015 survey, zearalenone was found to contaminate 66% of all silage samples tested. At levels above 50 ppb, zearalenone is known to cause problems with reproduction in dairy cattle. In addition, zearalenone can be transformed into more toxic metabolites by the rumen, namely, alpha-zearalenol and beta-zearalenol.

Although the rumen can partially degrade type B trichothecenes, such as DON, the level of contamination in 2015 was especially high with 78.3% of the samples contaminated with more than 500 ppb of DON. At these levels, type B trichothecenes can disturb the rumen flora and affect ingestion of the ration. Type A trichothecenes were found in only 10% of the samples, but their presence can aggravate the toxic effect of type B trichothecenes, and they can also be transformed into more toxic metabolites, notably DAS and MAS. Finally patulin toxin was also detected in the silage samples, at levels that pose a health risk to animals.

Emmy Koeleman Freelance editor

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