Moulds and mycotoxins generally grow sporadically throughout a field, with some areas clean and others high in mould.
If you are planning to submit a grain corn sample for mycotoxin testing, contact the lab you are dealing with to determine the proper way to obtain and ship the sample. However, here are some general guidelines.
If you plan to sample after combining, the importance of collecting a representative sample can not be emphasized enough, since 90 per cent of the variability associated with mycotoxin test results comes from incorrect sample collection.
This variation is primarily due to the uneven distribution of the mycotoxin contaminated kernels within a lot of grain or feed. Avoid taking a sample from the top of a storage bin, truck or combine since although it may be easy and very convenient, that method will not get you an accurate sample.
When it comes to sampling and an accurate mycotoxin test, the more samples taken, the better. If the sample is from a bin, truck, V-box or other stationary load of corn, a sample probe is recommended. Although 10 probes are recommended, five probes will do if necessary.
Mix the grouped sample and take a representative sample from this pooled sample. If you are dealing with a moving stream of grain, either use a diverter or randomly collect cupfuls (handfuls will work as well) of grain.
Regardless of how the sample is taken, it must be processed quickly! Therefore ship or deliver the sample promptly. The longer the sample sits around the greater potential of inaccurate results.
Sampling standing corn is a difficult process. Moulds and mycotoxins generally grow sporadically throughout a field, with some areas of clean corn and
other areas of high mould or “hot spots.” Take ears from several areas of the field to try and get a representative sample. Be sure to check with the lab as they may prefer a grain sample as opposed to receiving whole cobs.
For more information on sampling procedures, pricing, sample request forms and shipping instructions, contact the laboratories directly. Central Testing Laboratory Inc. (www.ctl.mb.ca)is at 9-851 Lagimodiere Blvd., Winnipeg, R2J 3K4 (phone 204-237-9128). North Dakota State University’s department of veterinary and microbiological sciences (www.vdl.ndsu.edu)is at Fargo, N. D., U. S., 58105 (phone 701-231-8307).
Livestock including swine, cattle, horses and poultry are susceptible to certain mycotoxins. Therefore any grain that is fed to livestock should be tested. For more information on feeds and feeding considerations, check out the following MAFRI website: http://www.gov.mb.ca/agriculture/livestock/beef/baa05s00.html.
– Pam de Rocquigny is a cereal specialist with Manitoba
Agriculture, Food and Rural Initiatives’ Crops Knowledge Centre at Carman.