Swine: Feeding Mycotoxin-infected Wheat
Feeding wheat to swine
Economics and mycotoxin levels will determine the most cost effective amount of wheat to include in a ration. In general, starter and grower-finisher rations can include up to 100% of the grain portion of the ration as wheat. In lactation and gestation diets wheat should be restricted to 50% of the grain portion of the ration. When wheat is used in pig feeds, close attention to feed processing and fineness of grind is essential to avoid problems with palatability, bridging in feeders and incidence of stomach ulcers. Mycotoxins tend to be concentrated in the hulls or outer covering of grains. As a result, mycotoxins may be as much as five times higher in grain by-products, such as wheat middlings or wheat shorts. This may be a year to be extra careful feeding these types of by-products on farm or in complete diets. Another point to remember is that mycotoxin-contaminated straw can be a source of toxicity, especially for gestating sows housed on straw that are being limit fed.
Guidelines for feeding mycotoxin-infected wheat
The optimum solution is to buy clean grain for swine and feed the contaminated grain to cattle. Feeder cattle should be able to safely consume levels five to 10 times higher than swine. If contaminated wheat must be fed, the following table lists maximum levels in swine diets for DON and ZONE. Please note that these levels should be adjusted downward if feed intake is reduced or other obvious signs of toxicity are observed.
|
Age Group |
Deoxynivalenol |
Zearalenone |
|
Nursery |
0.5 |
0.5 |
|
Grower-Finisher |
1.0 |
2.0 |
|
Lactation/Gestation |
1.0 |
0.5 |
* Source: Kansas Swine Nutrition Guide
Initial corrective steps for Fusarium infected wheat
* clean moldy grains, remove fines and light weight grains suspected of mycotoxin contamination.
* dilute mold or mycotoxin contaminated wheat with mold-free grains.
* if moderate effects on animals are noted, reduce the inclusion of the suspected wheat by 50% of
the amount in the ration.
* if effects on animals are severe, discontinue use of the wheat for at least a week. If improvements
are noted, sample the wheat and have it retested to determine the safe level to feed.
Practical nutritional steps that may help
* if mild contamination is suspected, increase the nutrient levels of the ration to help compensate for
the reduced intake.
* increase the levels of vitamins, minerals, and amino acids by 5-20% depending on severity of feed
refusal.
* add an appropriate mold inhibitor (sodium or calcium propionate or organic acids) to stored grain to
prevent further development of molds.
The extent to which this year's cereal crops are infected with mycotoxins is not yet known. However, if you are planning to feed new crop wheat or other small grains to swine, mycotoxin analysis and management steps to reduce contamination should be strongly considered.
Author: Greg Simpson - Swine Nutritionist/OMAFRA
August 2008 Pork News & Views newsletter
Government of Ontario Ministry of Agriculture, Food and Rural Affairs
Dear Mr. Greg Simpson,
In addition to my comments about Guidance Values for zearalenone, probably you know the article entitled: “Mycotoxins as a risk factor for the origin of diseases and production decreases in swine facilitiesan epidemiologic study” published in 1991 by Ewald.C Rehm.A and Haupt. C. (Tierärztlichen Ambulanz Schwarzenbek, Fachbereich Veterinärmedizin der Freien Universität Berlin), in Berl. Munch. Tierarztl. Wochenschr, May 1104(5):161-166. With the following abstract from, PMID: 1831348 [PubMed - indexed for MEDLINE]:
“Feed samples checked for the mycotoxins zearalenone and ochratoxin A from the harvest 1987 were positive at a markedly higher percentage (37.5%) compared to previous years, which is explained by the especially unfavourable harvesting conditions of 1987. In certain herd problems affecting the digestive or respiratory tract, mycotoxins could be detected with a much higher frequency (64.7% and 50.0% respectively). The mean level detected in feed samples by thin layer chromatography ranged within 30.3 ppb for zearalenone and within 58.3 ppb for ochratoxin A. In most cases there was a history of infertility. Considering the clinical situation, which is presented comparatively in herds with positive mycotoxin results, the possible involvement of mycotoxins in the disease, even at very low concentrations, is pointed out. In this context, zearalenone is incriminated of being an indicator of a multitoxic process besides its own direct effects. According to own experiences low levels of zearalenone in the range of 20-50 ppb in the feed have to be considered hazardous. If changing of pig feed in cases of herd problems will be recommended, a level of less than 10 ppb of zearalenone, especially in sow and piglet rations, should not be exceeded. Same may be valid to ochratoxin A.”
What is your opinion?
Should the EU revise and decrease the Guidance Values for zearalenone published in August 2006?
Should you revise and decrease substantially the Guidance Values for zearalenone showed in your article?
The best regards,
Gimeno
Dear Mr. Greg Simpson,
The Commission Recommendations of the European Communities (EU), published the 23rd of August 2006 (Official Journal of the European Union, 2006/576/EC) a Guidance Values for zearalenone and other mycotoxins in products intended for animal feed. In zearalenone the guidance values (ppm) relative to a complementary and complete feedingstuffs with a moisture content of 12% were as follows:
Complementary and complete feedingstuffs for piglets and gilts (young sows): 0.1 ppm
Complementary and complete feedingstuffs for sows and fattening pigs: 0.25 ppm
These maximum concentration levels recommended by EU are totally different to the maximum levels showed in your article.
Who is correct the EU or you?
I have noted that the guidance levels of your article were already published on the 18th of August 2000 by Janice Murphy, Swine Nutritionist/OMAFRA, in the article Molds and Mycotoxins-Feeding Mold and Mycotoxin Contaminated Corn to Swine, perhaps it is necessary to update your guidance values.
Personally, I observed serious estrogenic problems in sows (gestation/lactation) consuming during 7-14 days a contaminated mixed feed with 0.5 ppm of zearalenone (the mixed feed was not found contaminated with other mycotoxins, like vomitoxin) and with a daily feed consumption of 3 Kg for gestation and 6 Kg for lactation. You can note that the daily consumption of zearalenone was more than 1 mg zearalenone/sow per day. According to several authors, the daily zearalenone consumption value previously referred is critical in order to produce estrogenic problems.
Best Regards,
Gimeno
