This article written by Dr. Reynold Bergen, BCRC Science Director, originally appeared in the May 2020 issue of Canadian Cattlemen magazine and is reprinted on the BCRC Blog with permission of the publisher.
Statistics Canada reports that Western Canada’s silage corn acreage has grown significantly in recent years. Nearly 30% of seeded corn silage acres aren’t harvested, suggesting it’s likely being used for grazing. The potential for a 50% higher yield compared to barley may offset corn’s 30% higher input costs, but only if growing conditions are right.
It is critically important to pick a hybrid that can grow under local conditions. A hybrid with a higher corn heat unit (CHU) rating than local conditions provide will not have time to reach optimal maturity before it is harvested or frozen, and will contain more fiber, more moisture, fewer cobs and less starch than ideal. It will also be less palatable and nutritious, whether it’s harvested for silage or left for grazing. On the other hand, a short season hybrid grown in a historically hot area would be ready to harvest before the growing season is over, sacrificing some potential yield. Corn silage that is harvested too late will be too dry, making it harder to pack and reducing silage palatability. Not every year is ‘average’, and year-to-year variations in growing conditions also need to be considered before deciding whether to try corn, or which hybrid to try. Continue reading
This article written by Dr. Reynold Bergen, BCRC Science Director, originally appeared in the April 2020 issue of Canadian Cattlemen magazine and is reprinted on the BCRC Blog with permission of the publisher.
According to Statistics Canada, silage corn acreage was 26% higher in 2015-19 than in 2010-14. Most of this increase occurred in the Prairies. Achieving corn’s potential will depend on whether plant breeders can successfully adapt this warm season plant to Canada’s cooler climate.
Plants contain two kinds of carbohydrates. Non-structural carbohydrates are starches and sugars that help the plant store energy and are easily digested by livestock. Structural carbohydrates include the cellulose and hemicellulose fibers found in cell walls. Cellulose and hemicellulose, along with lignin, hold the leaves and stems together and help the plant stand up. Rumen microbes digest hemicellulose more easily than cellulose, but lignin is virtually indigestible. In a feed test, neutral detergent fiber (NDF) measures the amount of cellulose, hemicellulose and lignin. An indicator of “bulk”, high NDF levels limit animal intake. Acid detergent fiber (ADF) is the amount of less digestible cellulose and lignin (but not hemicellulose). Digestibility declines as NDF and ADF increase.
In perennial grasses, cellulose, hemicellulose and lignin levels increase steadily as the plant grows and matures. This makes sense; as the plant gets taller, it requires more structural integrity to keep standing. This is why ADF and NDF increase and digestibility decreases as grasses mature. Non-structural carbohydrates and protein levels rise initially, peak, and decline after grass has headed out. The amount of structural carbohydrate continues to increase as the plant matures and sets seed. That’s why the nutritional value of pasture generally declines as grass matures, and why rotational grazing practices that keep grass vegetative by ‘clipping’ and preventing it from heading out helps maintain the nutritional quality of the pasture later into the growing season. Continue reading
To maintain profitability w
ith rising feed grain prices, feedlots are required to consider alternatives to purchased grains. Traditionally forages are avoided because of their higher fiber content and lower energy content which leads to lower feed conversion efficiency and increased manure production. The highly variable energy content of corn silage makes it challenging to maintain animal growth rate when cattle are fed higher forage diets.
Research currently underway and funded by the National Check-off and Canada’s Beef Science Cluster is working to obtain Continue reading