Hybrid Rye an alternative to corn in Pig Diets

In order to achieve food security, the agri scientists are working on the new varieties of wheat and rice, sometimes hybrid also.  

In this line, the rye is a wheat-like cereal plant which tolerates poor soils and low temperatures. Whiskey in which a significant amount of the grain used in distillation is fermented rye. Rye since long has been the underdog grain, associated with the lower class and relegated to the status of “acquired taste.” But not everywhere. There are countries like Russia, Poland, all of Scandinavia that has long embraced rye, serving their coarse black bread proudly. Know more about this hearty winter grain with these fun facts. 

Rye is part of the Poaceae or Gramineae family (a.k.a “true grasses”). It’s related to wheat and barley but was long considered a weed in barley and wheat fields. The former Soviet Union had long been the biggest producer and consumer of rye and now the Russian Federation holds those titles. Canada grows more rye than the US and a good amount of the grain ends up us Canadian whiskey.

As it’s such a carb-rich grain, it can help make you feel full, even more so than eating wheat products, which in theory means you might eat less. Rye most often gets processed into flour for bread or fed to livestock. Most rye bread are a mix of rye and wheat flours, while Scandinavian-style black bread is made of pure rye flour. But baked goods aren’t the only way to consume rye. It’s used to make whiskey – both multigrain blends like bourbon and pure rye whiskey (and you can age it yourself, if you like). It’s also a base ingredient in many vodkas and gins. 

Whole rye berries can be boiled as a hearty alternative to a hot oatmeal breakfast or sprouted and sprinkled into salads. The berries are sweet and nutty, with that unmistakable rye flavor. It’s a good source of soluble fiber, vitamin E, calcium, iron, and potassium, and has been linked to a reduced risk of cardiovascular disease, colon cancer, breast cancer, and diabetes. Because rye is harder to refine than wheat, it retains more of its nutrients. 

Because it’s a robust grain that grows well in poor soils, it acquired this monicker. The fact that it was often harvested and eaten by impoverished communities surely reinforced this stereotype. 

It’s been used as a winter cover crop, especially in organic farming, for generations. Because it has deep roots, rye is able to capture nutrients, enhance soil health, prevent soil erosion, and reduce weeds without the use of herbicides. Rye has not traditionally been used as an ingredient in pig diets in the United States, but researchers from the University of Illinois are now investigating the digestibility of nutrients in the grain. 

Older hybrids of rye had low yields, the potential for toxic fungal contamination, and limited market demand. The little rye grown in the U.S. is typically consumed by humans in bread and other baked products or used in the beverage industry. But thanks to breeding advancements in Europe over the past 20 years, hybrid rye is producing far greater yields and is less susceptible to fungal contamination. Now those varieties are coming to the U.S. and Canada. 

“Because hybrid rye has greater yields than all other small grains including conventional rye in Europe, it is likely that hybrid rye can also out-yield other small grains such as sorghum, wheat, and barley on the drier soils in the United States and Canada. This may make hybrid rye an interesting ingredient in the feeding of pigs and other livestock species, but at this point, there is limited information about the nutritional value of hybrid rye when fed to pigs,” says Molly McGhee, a graduate student working with Hans Stein in the Department of Animal Sciences at U of I.   

McGhee and Stein have taken a first step toward understanding the nutritional value of hybrid rye with a study published in the Journal of Animal Science. In the experiment, seven growing barrows were consecutively fed diets consisting of barley, wheat, corn, and three types of hybrid rye; two grown in Europe and one in Canada. The grain, which was the sole source of amino acids and starch in each diet, was mixed with a small amount of soybean oil, vitamins, and minerals to meet nutritional requirements. A nitrogen-free diet based on cornstarch and sucrose was also included in the experiment as a control. 

McGhee collected samples of the ileal digesta - partially digested material in the ileum - from each diet and analyzed the digestibility of amino acids and starch. She also analyzed overall nutrient composition and mycotoxin content of each grain source prior to being fed to the pigs. The apparent ileal digestibility (AID) of starch was greater in wheat and corn than in barley or hybrid rye, but starch AID values in all diets were greater than 95 percent. Most amino acids were found in higher concentrations in hybrid rye than in corn, but they were less digestible in rye than in the other grains. The three rye hybrids did not differ substantially from each other in terms of nutrient composition or digestibility.    

“We think the amount of digestible amino acids was less in hybrid rye than in barley and wheat because they are higher in protein overall. Essentially, hybrid rye comes out in the middle of those other cereal grains for digestibility of both amino acids and starch,” Stein says. “Hybrid rye has the potential to be cost-effective in comparison with other cereal grains when used in diets for pigs.” 

Although the work is in its infancy – Stein and McGhee have several more experiments planned – the use of hybrid rye in pig diets could be attractive to U.S. farmers and the feed industry given the plant’s agronomic characteristics. It is drought tolerant, overwinters well in most locations, produces high yields, and is less expensive to grow than corn.