Rapeseed, Sunflower and Soybean Meals as Protein Supplements in Dairy Calf Starters

The world need for protein is ever-increasing causing the feed industry to seek new sources of protein supplementation for livestock (17). Urea and other non-protein-nitrogen (NPN) source have received much attention in the past twenty years as protein substitutes, but their use is limited to years as protein substitutes, but their use is limited to functional ruminant animals. Pre-ruminant calves, unable to utilize NPN, need natural protein in their diets. Soybean meal (SBN) has been the common protein supplement in many dry calf meals in the Midwest for several years and has been proven to be an acceptable source of both protein and energy. Since the early 1940’s the production of rapeseed (Brassica napis and B. campertris) in Canada has risen tremendously due to the increased demand for the extractable oil. Presently, rapeseed production is second only to flax as Canada’s most important oilseed crop, and it ranks first as Canada’s largest oilseed export (33). Rapeseed meal (RSN) has been marked for many years, but its acceptance has been plagued by toxicity and palatability problems due to its content of mustard oils. Recent developments in processing methods and plant breeding have considerably reduced the level of these undesirable oils. Compared to nonrumonants, the nutritional value of RSN for cattle has received limited attention because it is felt that ruminants are less susceptible than other classes of livestock to the effects of the toxic factors in RSM. Sunflower meal (SFM) is also gaining importance as a feed ingredient for the livestock industry. Again, the demand for the oil is resulting in more meal being available as a livestock feed. Sunflower production is of special interest because of the expected increase in contracted acreage in South Dakota within the next five years (45), Minimal information is available on SFM as a protein supplement for cattle, notably dairy. This study was designed to determine the feeding value of rapeseed, sunflower, and soybean meals as protein supplements in dairy calf starter rations. The objectives of the study were as follows: 1. To determine the rate of gain, feed efficiency and acceptability associated with each starter. 2. To determine the digestion coefficients for energy, dry matter and protein of each starter. 3. To determine the fate of the dietary protein by nitrogen balance technique. 4. To investigate the relationship between dietary protein and rumen volatile fatty acid (VFA) conten