Int’l - Tech Talk: Maintaining a guard against mycotoxins
Published:November 22, 2004
Source :British Pig Executive
Grain quality is likely to have been affected by bad weather during the harvest. Pig producers are urged to be extra vigilant to ensure the quality of cereal grains going into feed is maintained so pig health, feed intake and performance do not suffer.
The wet weather has delayed harvest and also led to high grain moisture content, which increases the risk of mycotoxin development during storage.
Proper grain storage is the key. HGCA has urged growers to focus on wellestablished basics of drying and cooling. HGCA Assistant Director of Research and Development, Dr Roger Williams said: “It is vital to dry the grain to below 18% moisture content as quickly as possible, then continue drying to 14.5% or below.
“Failure to do so will increase the risk of the mycotoxin ochratoxin A forming in stored grain. Subsequent cooling as quickly as possible is important to stop insects breeding.”
Work done by the VLA led Stan Done and Andrew Gresham to conclude that mycotoxicosis and particularly ochratoxicosis may be, at least in part, a factor in the development of PMWS and PDNS. Ergot is another watch point. MLC Pig Technical Manager, Dr Pinder Gill, said: “Depending on the level of contamination, ergot in feed grain will result in a serious reduction in intake, or even outright refusal of feed in young growing pigs, causing a marked growth check”.
MLC Senior Pig Scientist, Dr Jayne Thompson said: “The MLC welcomed the opportunity of working with the HGCA, on behalf of BPEX, to provide practical guidance for UK pig producers. “We are grateful to the HGCA for the information which will prove useful to producers in managing problems that could arise in the coming months, particularly if they grow their own cereals”.
Guidance on the best methods of drying, cooling and storing grain is provided by HGCA in their Grain Storage Guide and Topic Sheet No. 78, together with other practical information at www.hgca.com. Further information more specifically for pig producers will soon be available on www.bpex.org.uk and www.stotfold pigs.co.uk.
What to look for
1. PINK GRAIN: associated with Fusarium, although there are other causes that may affect feed quality. Where pink grain is caused by Fusarium, mycotoxins may be produced (HGCA surveys show levels rarely exceed proposed limits)
2. MOULDY GRAIN: appears dull and weathered, and may impair quality. The dullness results from moulds or spores that present an unacceptable risk of mycotoxin formation.
3. ERGOT (hard purple-black ‘sclerotia’ can be seen in the grain up to 2cm long, distinguishable from rodent droppings by grey/white insides): toxic to man and animals, particularly pigs, and is unacceptable.
Animal symptoms:
An unexpected and marked level of feed refusal may be associated with poor drying practices and grain contamination. Pigs (and other livestock) fed grain contaminated with ergot can show symptoms including gangrene, abortion, failure to lactate and possible death. A resurgence of PMWS-related problems may be associated with mycotoxicosis that could result from fungal and mycotoxin contamination of grain used in pig feed.
