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Production area does not affect phosphorus digestibility in soybean meal fed to pigs

Published July 26, 2016


·         The chemical composition of soybean meal can be dependent on the area in which soybeans are grown.

·         Soybean meal from three different growing areas in the U.S. showed no statistical differences in concentrations of phosphorus.

·         An average value for apparent and standardized total tract digestibility may be used, regardless of the area in which soybeans are grown.

URBANA, Ill. – Research at the University of Illinois is helping to determine the effect of growing conditions on the nutritional value of soybean meal. "The digestibility of phosphorus is the same in soybean meal grown in various regions in the United States,” says Hans Stein, professor of animal sciences at Illinois.

"The chemical composition of soybean meal is somewhat dependent on the area in which soybeans are grown, but it was not known if there are differences in the concentration of phytate among soybeans grown in different areas," Stein says. He and Kelly Sotak-Peper, then a doctoral candidate, set out to determine whether any differences existed.

They sourced soybean meal from crushing plants in three different areas within the United States: the northern growing area (comprising Michigan, Minnesota, and South Dakota), eastern growing area (Georgia, Illinois, Indiana, and Ohio), and western growing area (Iowa, Missouri, and Nebraska).

They measured no statistically significant differences in concentrations of phosphorus, or in the percentage of phosphorus bound to phytate, among soybean meal from the different regions. There were also no differences in apparent total tract digestibility (ATTD) or standardized total tract digestibility (STTD) among pigs fed soybean meal from the three growing areas.

When microbial phytase was added to the diets to break down phytate, the ATTD and STTD of phosphorus for soybean meal from all growing areas increased by 24 and 22 percent, respectively.

"When you have ingredients that come from a wide variety of growing conditions, there's a risk that using book values for nutritional information will not give you accurate information for a given batch," says Stein. "What these data indicate is that an average value for ATTD and STTD of phosphorus may be used regardless of the area in which the soybeans are grown."

The research was supported by funding from the USDA National Institute of Food and Agriculture. Soybean meal was donated by AG Processing Inc., Omaha, NE; Archer Daniels Midland Company, Decatur, Ill; Bunge North America, St. Louis, Mo.; and Cargill Inc., Elk River, Minn.

The paper, "Effects of production area and microbial phytase on the apparent and standardized total tract digestibility of phosphorus in soybean meal fed to growing pigs," was published in the June 2016 issue of the Journal of Animal Science. The full text can be found at

Rainforest greener during “dry” season

Published July 26, 2016
  • At 2.7 million square miles, the Amazon Jungle is the world’s largest rainforest.
  • Researchers now believe the rainforest has different levels of photosynthesis, with more during the dry season.
  • More extreme droughts due to climate change could negatively affect the rainforest’s ability to sequester carbon through photosynthesis.

URBANA, Ill. –  Although the Amazon Jungle may appear to be perpetually green, a University of Illinois researcher believes there are actually seasonal differences of photosynthesis, with more occurring during the dry season and less during the wet season. Understanding how a rainforest that occupies 2.7 million square miles of South America functions is crucial to the future health of the entire planet.

“With the potential negative effects of climate change, one key question we are trying to answer in the study of tropical ecology is how a tropical forest responds during a long-term drought,” says Kaiyu Guan, an environmental scientist at the University of Illinois. “If we don’t know their daily performance or their seasonal performance, what confidence can we have to predict the forests’ future 20 years, 30 years, or longer?”

Analyzing data from several sources, including individual leaves, camera data from towers above the leaf canopy, and decadal long satellite images, Guan and his colleagues measured the photosynthesis rate over the landscape. Photosynthesis—the process green plants use to convert energy from the sun that plants use to grow—from tropical forests, plays a huge role in determining global atmospheric CO2 concentration, which is closely linked the global temperature and rate of climate change.

 “Bringing all of the data together, we find that the dry season in the Amazon has increased photosynthesis,” says Guan. “There may be less photosynthesis in the wet season because of the cloud cover which limits the amount of light the plants can use.”

Guan explains that understanding the seasonality of photosynthesis can help scientists assess whether or not the Amazon is under stress and how it handles and recovers from stress.

“During the dry season, you would think that the plants would be water stressed and photosynthesis would decrease, but looking at multiple sources of data over the years we find that the plants are not stressed because there is ground water carried over from the previous year,” he says.

It does not appear to be just the quantity of leaves driving the higher photosynthesis during the dry season. Guan and his collaborators believe it is actually leaf quality which changes over leaf age that is at work.

“Leaf amount can only explain about 5 percent of all the photosynthesis variations, so what’s really going on? It’s the leaf quality. Putting it in a different way, when you are a baby, you aren’t very productive. When you become more mature, you’re more productive. Then, when you’re older, your productivity goes down again. It’s true for humans and it’s also true for plants. Leaves in tropical forests that are 3 or 4 months old are more productive. As you get to the end of the dry season, the leaves are aging and their productivity decreases again. So the combination of the leaf amount and the leaf quality together can satisfactorily explain the pattern,” Guan says.

Guan cautions that if the forest experiences several droughts, the carryover of water is depleted—the tropical forest responds to the climate.

“The rainforest also absorbs the majority of carbon,” Guan says. “It’s the engine that drives the carbon cycle for the whole world, which makes it important when we discuss climate changes. Global warming is dependent upon the atmospheric CO2 concentration, so we need to care about carbon.

“Most of the climate models are showing a drying down trend in tropical forests, with a longer dry season. That’s a cause for concern for the future of the Amazon,” Guan says. “If we neglect it, it can have consequences around the globe. We need to recognize the importance of this rainforest pattern in which our entire global ecosystem functions. The healthiness of these systems is highly relevant for human beings.”

In addition to being an assistant professor in ecohydrology and geoinformatics in the Department of Natural Resources and Environmental Sciences in the College of Agricultural, Consumer and Environmental Sciences at U of I, Guan has a joint appointment as a Blue Waters professor affiliated with the National Center for Supercomputing Applications (NCSA).

Using the same satellite technology, Guan is currently looking at agricultural systems in tropical and temperate regions like the U.S. Corn Belt. “We’d like to build a satellite-based system to monitor the entire United States food productivity in order to predict the crop yield.”

The above report is based on four recent articles that appear in Science, Nature, Nature Geoscience, and Global Change Biology with Guan as lead author or co-author along with researchers from institutions in the United States from Arizona, Massachusetts, Michigan, New Mexico, and California, as well as from Brazil, Australia, and Japan.

News Source:

Kaiyu Guan

Cattle markets can recover

Published July 25, 2016

URBANA, Ill. – Lower cattle prices have been the story this spring and summer. Beef supply has been large due to heavy placements of heavy calves and the beginning of more females coming to market as herd expansion may be slowing. According to a Purdue University Extension economist, retail beef prices have been slow to come down and this has limited consumer purchases of beef in relation to abundant pork and poultry supplies.

“Finished cattle prices have been on the skids since mid-March when prices reached near $140 per hundredweight,” says Chris Hurt. “By last week, prices had fallen to around $115. Noticing the bearish theme in the cash market, the futures market has suggested prices will drop another $5 by the end of this year and proceed downward to near $100 by next summer.”

Hurt says there are plenty of reasons why prices have fallen, the biggest being a large number of cattle coming out of feedlots in recent months.

“That story goes back even further to abundant grass which encouraged cow-calf operations and backgrounders to add more weight to calves before they entered the feedlot,” Hurt says. “As a result, there has been a shift to heavier weight placements. In the first half of this year, placements weighing 800 pounds and more represented a record 40 percent of all placements, compared to a longer-term average around 27 percent.”

According to Hurt, rapid placements of heavy calves meant that marketings were going to rise sharply. Marketings out of feedlots were up 5 percent in May and then up a sharp 10 percent in June. Contributing to higher recent marketings has been a shift to lower slaughter weights since May which has served to “pull cattle forward.” This shift to lighter weights is probably related to the falling finished cattle prices and the desire of feedlot managers to get cattle to market before prices dropped even more.

Because of these heavy marketings, beef production was up 5 percent in May and 10 percent in June compared to the same month in the previous year. The rapid marketings in recent months has reduced the total number on feed to just 1 percent higher than a year ago according to USDA. This should help ease the burdensome volume of cattle and encourage upward price movement.

Hurt says there are early signs that the expansion phase of this cattle cycle could be in the process of slowing. Lower finished cattle prices and extremely weak futures prices may be causing cattle producers to rethink any additional expansion plans. The calf prices implied by $100 finished cattle is simply not profitable for most cow-calf operations. If producers slow the rate of expansion, more females move to market providing added beef supply pressures to already declining cattle prices.

“The signs of slowing expansion are in the rate of increased female slaughter,” Hurt says. In June, the number of heifers processed was up relative to year-previous levels for the first time in several years. In addition, the number of beef cows processed in both May and June was up about 18 percent. For June, total females (heifers and all cows) processed were up 7 percent compared to year-earlier numbers.

“The total number of females in the processing mix remains low, so it is still too early to say this expansion phase has come to an end,” he adds. “However, these signs of higher numbers of females in the processing mix may be the first clues of what is to come. 

“Retail beef prices have been slow to fall as much as needed to encourage consumers to buy the added beef supplies,” Hurt continues. “In June, USDA reported the composite retail beef price was $6.20 per pound. This compares to a record-high price of $6.41 per pound in May 2015. Recent retail prices were just 3 percent lower than the record high. In contrast, June retail pork prices were down 11 percent from their high.”

Farm level prices normally drop quickly, but retail prices are much slower to decline, Hurt says. This means the current margin between the farm price and the retail price is at a record-wide level. Packer margins are likely at record-high levels as well.

“As retail prices adjust downward over time, consumers will have more price incentives to buy beef and this could actually help strengthen farm level prices,” Hurt says. 

With the number of cattle on feed only up 1 percent on July 1, there should be renewed hope for recovery in cattle prices, Hurt says. “The fact that marketing weights have come down is also an encouragement that feedlot managers are more current in their marketings. In addition, over coming months, retail beef prices should also come down which will serve to narrow packer margins, but improve farm prices.”

According to Hurt, prices of finished cattle are expected to be in the mid-to-higher teens in the third quarter then move upward to the high teens to low $120s this fall.

“Recent live cattle futures prices have been extremely depressed, sending signals of much lower cash prices next year,” Hurt says. “Although prices are expected to be lower next year, they may not be as low as suggested by futures. Still, cow-calf managers will want to continue to be cautious about further expansion of the brood cowherd.”


Industries and researchers join to improve manufacturing drying processes

Published July 25, 2016
Hao Feng (righ) in lab

URBANA, Ill.  – One of the most energy-intensive stages in manufacturing paper, food, textiles, chemicals, and many other products is drying. Researchers from two colleges at the University of Illinois are working together to find more efficient and environmentally sustainable drying alternatives through a new research center, an effort sponsored by the National Science Foundation through its Industry/University Cooperative Research Centers program.

The new Center for Advanced Research in Drying is led by Jamal Yagoobi from the Department of Mechanical Engineering at Worchester Polytechnic Institute in Massachusetts. Hao Feng, who is a food science researcher in the College of Agricultural, Consumer and Environmental Sciences at Illinois, will serve as the Urbana-Champaign campus site director for the center.

“The drying process has a direct effect on product quality, from the nutritional value of food to the durability of paper products and textiles,” says Feng. “Inefficient drying processes also create a significant environmental impact. By working to improve the drying process, we can enable production of products with better quality, speed up the delivery of products, and increase manufacturers’ profit margin so everyone benefits, and we can reduce its adverse effects on the environment.”

Irfan Ahmad, from U of I’s College of Engineering, is co-principal investigator/co-site and innovation director of the center. Ahmad is also executive director at the Center for Nanoscale Science and Technology, and a research faculty member in the Department of Agricultural and Biological Engineering.

“Innovation is at the heart of CARD to address such challenges as energy conservation, climate change, product safety and quality, using novel technologies such as micro and nanotechnology-based smart sensors and drying nozzles,” says Ahmad. “It also envisages new engineering education programs to nurture innovation in drying as a vital core competency for the next generation workforce.”

As defined by NSF’s I/UCRC program, the center must demonstrate measureable industry collaboration and involvement that accelerates fundamental research.  Evidence of industry-defined fundamental research must show that the proposed industry participation extends the center’s capabilities into areas or projects that might not otherwise be researched.

NSF provides a framework for industries, universities, and the government to join together to solve problems that require a multi-disciplinary effort such as this one. Over 30 industry, organization, and government partners have shared their enthusiasm and financial support for the center’s research on drying.

It is the first center in the United States dedicated to developing energy-efficient technologies for drying moist, porous materials, a problem affecting the competitiveness of U.S. manufacturers across a wide range of industries. The center is one of three NSF I/UCRC centers led or co-led by University of Illinois researchers.

"Innovative drying technologies are critical to advanced, sustainable manufacturing technologies.  Numerous challenges remain to be tackled with tangible academia-industry interaction such as CARD. I am sure CARD will play a leadership role in making a definitive contribution to the national and global effort in this field", says Arun Majumdar, editor-in-chief of Drying Technology, and emeritus professor of bioresource engineering at McGill University in Canada.

For more information, visit the Center for Advanced Research in Drying.





New book explains importance of great river management

Published July 25, 2016
book cover

URBANA, Ill. – University of Illinois soil scientist Ken Olson and his colleague, Lois Wright Morton, a sociologist from Iowa State University, have examined the effects of climate extremes including flooding and droughts in the Mississippi and Ohio River basins from many angles. They’ve co-authored over 20 feature journal articles and recently completed a book on the subject.

Managing Mississippi and Ohio River Landscapes explores the complex and ever-changing Mississippi and Ohio Rivers' landscapes and their systems. In this new century three major concerns have emerged: climate change and impacts, food insecurity, and homeland security including infrastructure, navigation, and water supplies. All three themes run throughout this book. 

Through a series of engaging case studies accompanied by illustrative maps and photographs, the book reviews the historical impacts of climate, economic and population growth, and efforts to manage the waterways with engineered structures. Topics include drainage of bottomlands for crop production and other land uses, flooding risks and responses, levee systems and breaches, river navigation, and river ecology. The book concludes with recommendations for future management of these major waterways in the United States.

The hardbound book is 240 full-color pages. Managing Mississippi and Ohio River Landscapes can be pre-ordered online from the Soil and Water Conservation Society website.