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A recent study by fertilizer experts from the University of Western Australia has shown that there is a direct link between crop residue and nitrogen availability in crops. While the study analysed only nitrogen application and uptake in wheat, it is likely that a similar effect takes place across all crop types.

The research paves the way for farmers and fertilizer manufacturers to develop techniques and application methods that could prevent nitrogen fertilizers from coming into contact with plant residues. This would increase efficiency, limit waste and by reducing run off, be better for the environment.

The research was conducted by Nathan Craig, in a study supported by the Grains Research and Development Corporation (GRDC), a government funded research foundation that aims for, “improvements in production, sustainability and profitability across the Australian grains industry.”

Reporting on the breakthrough, the industry journal Agronomist and Arable Farmer stated that, “The aim of the study was to quantify the supply of nitrogen to wheat crops from the soil and crop residue and determine the effect on grain yield and grain nitrogen uptake – in a monoculture wheat rotation and a chickpea-canola-wheat rotation.” Adding that, “Research was conducted at the Western Australia No-Tillage Farmers Association (WANTFA) long-term no-tillage trial site at Cunderdin in WA’s central grainbelt.”

Craig’s study showed the clear benefits of applying nitrogen fertilizer, when it concluded that, “Across the three seasons tested, there was an overall benefit of applying nitrogen fertilizer to monoculture wheat, which increased grain yield and grain nitrogen uptake in most years, and effectively closed the yield gap between wheat grown in monoculture and wheat grown in rotation with legume crops and with no nitrogen fertilizer added.” However, Mr Craig also added that, “The application of nitrogen fertilizer actually reduced the mineralisation of nitrogen in the soil in the monoculture wheat system, whereas in the rotated wheat system there was less effect.”

But most interesting in the study, was the impact that the left over plants and pieces of crop from previous seasons had on nitrogen levels in the soil. Something that Craig outlined when he said, “While retaining crop residue is known to improve nutrient recycling in no-tillage systems in the longer term, the potential for nitrogen to be immobilised in the short term during decomposition by microbial activity could provide significant competition for plant available nitrogen in the soil during the growing season.”

Craig also added that, “More importantly, when soil mineral nitrogen levels were low at seeding, and the crop residue carbon-to-nitrogen ratio was high, there was a high risk of immobilisation of nitrogen in both of the wheat systems.”

If the research results hold true, then there is a clear opportunity for farmers to reduce nitrogen fertilizer needs by adapting new crop management techniques, or by applying the fertilizer in a different, more effective way, so that it avoids contact with crop residue, or avoids the soil surface where mineralisation of nitrogen is concentrated.

One such technique that Craig himself suggested was, “An annual sampling program could be conducted at the start of each growing season to determine the carbon-to-nitrogen ratio of the crop residue mix left on the soil surface, and the amount of nitrogen in the soil to a depth of 10cm. From this, you could estimate the potential for immobilisation of nitrogen following fertilizer application.” This could, Craig claims, “be achieved using existing technology where additional nitrogen fertilizer is applied at seeding and ‘banded’ below the seed at a depth greater than 5cm, rather than an in-crop broadcast application during the season.”

Craig believes that this would increase the efficiency of uptake of nitrogen in crops, meaning that less fertilizer would be needed.

While there has already been a great deal of study in the fertilizer industry to find more efficient ways to apply agriproducts, this discovery will further increase pressure on nitrogen fertilizer suppliers and manufacturers to find a more effective way to get nitrogen products to crops. The three year analysis of mineralization and nitrogen uptake in wheat gives a key insight into exactly where and how so much nitrogen fertilizer is being wasted.

By analysing exactly where in the soil nitrogen is most available for crops, then perhaps the industry will also be able to develop a more effective method of applying such a vital product. However, if this research is accepted fully by the fertilizer industry, then one question remains: should fertilizer manufacturers develop an improved application method to help crops absorb more nitrogen, or is it purely the farmer’s role to consider the effect of crop residue on nitrogen fertilizers?

Photo credit: Grains Research and Development Corporation

The International Production and Processing Expo (IPPE) is billed as, “the world’s largest annual poultry, meat and feed industry event of its kind.”A bold claim, yet one that is well lived up to, with the 2017 conference attracting more than 31,000 visitors from key industry institutes such as the North American Meat Assoc., the US Poultry and Egg Assoc., and the American Feed Industry Assoc., as well as some of the most influential commercial enterprises.

In addition to the sales and marketing side of the event, it is interesting to note the importance of R&D in the expo’s proceedings, as it includes the International Poultry Scientific Forum. A collection of experts in the field of poultry health, egg and meat production science, and animal feed innovations, who get to share new ideas and discuss the challenges facing the livestock industry.

A key part of this is the publication of the Abstracts from the forum. This year’s edition was notable for the discussions held on the reduction, and where possible replacement, of antibiotics in animal feed. As the keynote speaker, Charles Hofacre, from the Dept. of Avian Medicine at the University of Georgia, notes, “There are many reasons broiler companies may choose to no longer routinely feed antibiotics in their broiler diets. There are also the new FDA regulations that remove the label claim for many antibiotics for performance enhancement, however, the labels allow for use in disease prevention. All of these changes may result in less routine use of in feed antibiotics.”

However, it is also interesting to see the large amount of research being conducted in the field of phosphate and zinc oxide feed additives. Especially given global concerns over uncertain phosphate supply chains, and increasing demands for sustainable livestock feed. Together these problems are making animal rearing efficiency a key challenge for the feed industry as a whole.

With this in mind, here are some of the main discoveries presented at the expo for poultry feed phosphate and zinc oxide additives.

1. The effects of dietary bee venom on growth performance, meat quality, immune response and gut health in broiler chicks.

This exciting piece of research was carried out by a team from Konkuk University in Seoul, the Korean Rural Development Administration, and the Eagle Vet Tech. Co., with aims to study the effect of bee venom as a feed additive for broiler hens. From a total of 700 male broiler hens, the experiments were carried out over 35 days, with four variations. As the study’s authors note, “A corn-soybean meal base diet was used as the control diet, and the experimental diets were formulated by adding honey bee venom (BV) into the basal diet to reach 10, 50, and 100μg BV per kg of diet.”

Interestingly, while the bee venom did not effect, “ileal sIgA concentration, intestinal morphology and cecal short-chain fatty acids,” it did have an impact on other key areas. As the authors note, “feed conversion ratio and weight gain were improved linearly at 1-21 days and at 1-35 days as the BV level in diet increased. Relative breast meat yields also increased linearly at 21 days with the increasing BV levels in diets.”

This led them to conclude that, “Taken together, dietary BV increased growth performance, and breast meat yields in broiler chicks.”

2. The importance of the source of zinc oxide in broiler hens.

“The objective of the study was to evaluate Zn bioavailability in three sources of zinc oxide (ZnO): two sources available on the European (ZnE) and the American (ZnA) market and a novel source (ZnHZ, HiZox®), using ZnSO4 monohydrate (ZnS) as a reference. A low-Zn basal diet was formulated in which plant feedstuffs were the only source of Zn (22 ppm). Twelve other diets were then prepared by adding to the basal diet 7, 14 or 21 ppm of Zn for each source.”

The results indicated that there is a significant link between how zinc is processed and the amounts of zinc that are absorbed by hens. But perhaps even more surprisingly, is that the researchers also found a link to where zinc as a dietary additive is sourced, and the amount of zinc the birds ingested. Clearly there are significant differences between American and European sourced zinc, and that has a real impact on bird health.

Additionally, similar research by Xi Wang, Timothy John from the University of Minnesota, and Wei Zhai from Mississippi State University, concluded that, “… extra zinc supplementation may inhibit the growth of Clostridium pathogens in broilers.”

3. The importance of sourcing organic or inorganic feed supplements for zinc, copper and manganese.

A study by a team from Zinpro, a supplier of performance minerals, aimed to find the importance of organic or inorganic feed supplements in broiler hens. By testing out a variety of combinations of organic and inorganic feed supplements, and comparing it to bird health, the researchers discovered that, “The feed conversion ratio was affected by diet and broilers fed with only organic minerals exhibited the worse production efficiency factor.”

4. Effect of potassium and available phosphorus in broiler breeder diets on fecal and egg characteristics at the onset of lay.

A study conducted by Dinabandhu Joardar, Coltin Caraway, and John Brake, all of North Carolina State University, analysed the problem of wet feces in chickens. This may affect egg laying ability as, “Hydrogen (H) ions, produced during egg shell calcification that are not buffered by the phosphate system in the kidney, are excreted in the form of water utilizing the bicarbonate buffer system.”

By adjusting the amount of available potassium and phosphate in the diets of broiler hens at the age of 22 weeks, the researchers were able to lower the moisture content in the faeces. However, raising the level of available phosphate had a negative effect on the birds.

As the report states, “A 0.3% Available Phosphate grower diet increased the weights of the second egg and its albumen.” Before adding that, “These findings could be beneficial in controlling excess litter moisture during onset of lay in broiler breeders.”

The Impact of Poultry Feed Additive Research.

While the impact of each of these individual pieces of research may be small, it is interesting to note the depth of analysis to which the animal feed additive industry is going to optimise both animal health and profitability. Continuing study on typical feed additives, such as zinc oxide and phosphate, is still making discoveries, and showing us how much more we need to learn to perfect feed mixtures. Analysis of new feed additives, such as bee venom, show us how complex the animal feed industry can be.

But if any of this research is to have an impact then cooperation between animal feed suppliers and livestock farmers will be vital. Forming closer ties between users and suppliers will ensure that animal feed additives are applied timely, and with the correct quantities, allowing the industry to maximise its potential. This will prevent wasting product as well as improving animal welfare.

Discoveries like these, show how much the industry cares about minimising waste, and therefore costs, and how much it cares about maximising animal welfare, and therefore profit. But which of these four studies on broiler hen feed additives will have the biggest impact?

Photo credit: CountrysideDaily

An ambitious new project is underway at Stanford University, as a team of scientists are hoping to replace the Haber-Bosch process for the manufacture of fertilizer.

With the energy consumed in the Haber-Bosch process contributing to climate change, if the research is successful then they may help solve two of mankind’s most pressing problems:
• How to feed a growing population
• How to use less fossil fuels

The team is based at the SUNCAT Center for Interface Science and Catalysis, a partnership between researchers from Stanford Engineering and the SLAC National Accelerator Laboratory. Where the team, “… is developing a fertilizer production process that can feed the world in an environmentally sustainable way,” says chemical engineer and SUNCAT director, Jens Norskov.

The SUNCAT project is being funded by a $7 million grant from the Villum Foundation, an international scientific and environmental philanthropy, which is focused on sustainable industrial chemicals, including a sustainable nitrogen-based fertilizer.

“One common thread across these projects is the need to identify catalysts that can promote chemical processes powered by sunlight, instead of relying on the fossil fuels now commonly used as energy sources and, often, as feedstock for reactions,” says Norskov. “We know of no manmade catalysts that can do what we require, [so] we will have to design them.”

Tom Jaramillo, deputy director of the SUNCAT Center and a member of the nitrogen synthesis project, put annual fertilizer production into perspective when he said, “Each year we produce more than 20 kilograms of ammonia per person for every person on the planet, and most of that ammonia is used for fertilizer.”

“We literally feed the world on fertilizers derived from the Haber-Bosch process,” adds Norskov. But the process is far from efficient, with the online scientific journal Phys.org, even stating that, “Due to the heat and pressure required by the Haber-Bosch process, ammonia catalysis accounts for approximately 1% of all global energy use. On top of that, between 3% and 5% of the world’s natural gas is used as a feedstock to provide the hydrogen for ammonia synthesis.”

Typically this process is carried out in large chemical plants, which adds cost to the fertilizer when fuel for transportation to the farm is factored in. To avoid this, the team is taking a different approach.

“We will harness solar energy in the presence of properly designed catalysts to create ammonia right in the agricultural fields. Think of it as a drip irrigation method of synthesizing ammonia, where it percolates into the roots of the crops.”

The theory behind the research is almost utopian; removing the need for fossil fuels as both a fertilizer feedstock and as an energy source, and with all processes working in the field, transportation costs will be miniscule.

As Norskovs explains, “You won’t need tremendous quantities of fossil fuels as an ammonia feedstock, or to drive the trucks that deliver the fertilizers or the tractors that apply it. And you won’t have a problem with excess application and fertilizer runoff, because virtually all the fertilizer that is produced will be consumed completely by the crops.”

Reporting on the SUNCAT team, the Phys.org report adds that, “The researchers aim to provide the benefits of fertilization without any of these [fossil fuel, transportation, application, feedstock] costs. The idea is to replace the centralized, fossil-fuel based Haber-Bosch process with a distributed network of ammonia-on-demand production modules run off renewable energy. These modules would use solar power to pull nitrogen from the atmosphere and also to catalyze the splitting of water molecules to get hydrogen and oxygen. The catalytic processes would then unite one nitrogen atom to three hydrogen atoms to produce ammonia, with oxygen as a waste product.”

However, finding the catalyst that can perform the function required will be far from easy. A point highlighted by Stacey Bent, a professor of chemical engineering at Stanford and a key member of the SUNCAT team, when she said, “While the catalyst must bind strongly enough to the target molecule to do the work required, it also has to release the end product.”

Jaramillo agrees, highlighting the complex chemical process that will need to be engineered. He said, “We have to design a series of reactions to cleave the nitrogen molecule from air, separate the hydrogen from water and combine them to form ammonia, with the only input energy coming from solar power.”

At the same time, there are other factors to consider in finding a catalyst, as the research team is aware that their end product must have a practical application. As Bent notes, “We have to design catalysts that can make and break bonds with atomic precision, and we have to ensure these materials can be mass produced at the necessary scales and price points, and are durable and simple to use in the fields.”

The challenge is clearly immense, but then so is the prize.

“Sustainable nitrogen production will only become possible with the cross-disciplinary collaboration of people working in fields such as materials science, chemical engineering and computer science,” Bent says. “It could literally change the world.”

And it seems that the researchers have the tools to make the dream a reality. “We are part of a very strong team, attacking some of the biggest challenges in chemistry, chemical engineering and sustainability,” says Jaramillo. Before adding, “We’re really just at the beginning.”

As they say, every journey begins with a single step, so being at the start of something holds no shame. How much scepticism Haber and Bosch received on beginning their journey is not known, but they must both have held large amounts of self-belief to achieve their goals; something that is clearly not missing from the SUNCAT team.

“Essentially we are attempting to restore the balance in the Earth’s carbon and nitrogen cycles that has been lost through the exponential increase in the demand for food and fossil fuels,” says Norskov. “The time to act is now.”

Like all great plans, it has strength in its simplicity. The challenge will come in working out the details, and in finding the exact catalysts that will work in harmony to provide solar-powered, in-field manufactured fertilizer. Whether they can complete their task and find a much needed replacement for the Haber-Bosch process, only time will tell.

Credit: iStock/yupiyan