It is never too early to start thinking about what grain will be used in winter rations. This year in particular, it is very important to purchase high quality feed grain. Ergot contamination is proving to be an issue of concern as this year, not just wheat – but oats, barley and triticale are testing positive for ergot. And, not just grain, but ergot is a concern in some mature forage crops as well. It is more important than ever to be aware of this problem and do the necessary testing when sourcing feed grain.
“Ergot is a plant disease caused by the Claviceps purpurea fungus and this year has been found in rye, triticale, wheat, barley, bromegrass, wheatgrass, bluegrass, quack grass, orchardgrass, meadow foxtail and wild rye,” says Barry Yaremcio, beef and forage specialist with Alberta Agriculture and Rural Development. “Ergot is most easily recognized by the hard, black bodies that replace the kernels on the seed head.”
Ergot overwinters as black, grain-sized fungal structures. In the spring, these germinate and form mushroom-like structures that produce spores which are carried by the wind to flowering cereals and grasses. Cool, damp weather in late spring and early summer increases ergot infection due to the longer flowering time of cereals and grasses in these environmental conditions.
“Ergot contains seven toxic alkaloids that negatively affect the health of livestock,” says Yaremcio. “General symptoms of ergot poisoning include lameness, excitability, belligerence, loss of appetite, pneumonias, weight loss, hair loss, foot rot and hoof sluffing. It can take two to eight weeks for these symptoms to become visible.
“The upper feeding limit of ergot in older, non-pregnant cattle was previously set at 0.1 per cent by weight of feed consumed. Some new research coming out of the University of Saskatchewan is causing this 1-in-1000 kernels ratio to be re-evaluated, and it is suspected that the 0.1 per cent is too high. Health issues have occurred when there were four (4) ergot bodies in 10,000 kernels of grain (approximately 1 pound). Preliminary testing at the University of Saskatchewan has established that the alkaloid content in Western Canada ergot samples are much higher than the values cited from research done in the southern US. So, always try to feed ergot-free feed to all your cattle. Pregnant, breeding and lactating animals are the most sensitive to ergot – they should not be fed any ergot at all.”
It is difficult to provide an answer to ‘what amount of ergot’ can be safely fed to livestock. Three factors come into play:
The type of animal being fed. Young animals vs older animal; animal condition and overall health status
How much grain is fed on a daily basis
The amount of ergot in the sample and concentration of the alkaloids present in the ergot
If ergot is present, a representative sample should be submitted for testing before it is used. For a list of where to send feed grain and forage for testing, contact the Ag-Info Centre toll-free at 310-FARM (3276). Cost of analysing feed is $63 through the University of Saskatchewan.
“There are four specific syndromes caused by ergot: gangrenous ergotism, convulsive/nervous ergotism, reproductive ergotism and hyperthermic ergotism. The gangrenous and nervous forms are most common.”
Gangrenous ergotism is associated with longer term ingestion of ergot. Ergot alkaloids cause small blood vessels to constrict, reducing the blood supply to limbs, tails, teats and ears. If blood flow is restricted for long periods of time, the tissues become oxygen-deprived and die. Hooves can slough off and, in cold weather, ears freeze off.
Convulsive, or nervous ergotism is more common in horses and sheep, and is the acute form of ergotism. Symptoms include dizziness, drowsiness, convulsions, paralysis and death. These symptoms usually disappear about three to 10 days after the ergot is removed.
Reproductive ergotism is caused by high levels of estrogen in the ergot bodies. This can lead to abortions or lowered fertility due to abnormal cycling. Once the ergot is removed, it takes a long time for estrogen levels to return to normal.
Hyperthermic ergotism results from long-term exposure to ergot. It is made worse on hot and humid days with no shade. Animals pant and lose weight.
“A few things to think about are the use of commercial screening pellets or grain screenings you can buy from the local seed cleaning plant. Ask if there is ergot present in the product you are purchasing. Levels in these screenings can be very high. If ergot is present, it may be necessary to dilute these feeds with clean grain to reduce the amount of alkaloids consumed on a daily basis.”
Source: Alberta Pork