Innovative developments in the production and delivery of alternative protein sources - Douglas L. Hard

Douglas L. Hard
V.P. Regulatory Affairs and Public Acceptance
Renessen L.L.C. Bannockburn, Illinois -USA

INTRODUCTION

The Food and Agriculture Organization (FAO) of the United Nations has called upon governments around the world to implement national action plans to control the spread of bovine spongiform encephalopathy (BSE), commonly known as mad cow disease. Important to blocking this spread is disciplined management of animal movement and the responsible disposition of animal protein by-products, which includes strict adherence to established feeding guidelines. Furthermore, the FAO has recommended a global ban on the feeding of mammalian meat and bone meal (MBM) to cattle, sheep and goats (FAO, 2001). In the past, meat and bone meal has been a primary protein source in animal diets in many world areas. To reduce the risk of infection even further, the FAO is encouraging governments to extend the MBM ban to the feeding of all animals.

Under the current model for BSE transmission, the spread of BSE could be blocked without the use of alternative protein sources if established feeding guidelines were strictly followed. However, livestock productivity would be severely compromised if quality protein levels in animal diets were not adequately maintained. Many countries already have animal production systems in place that rely solely on locally available protein sources. Other countries will be impacted to a greater extent as their livestock feed sectors search for ways to make up the anticipated protein shortfall.

World population growth is another important reason to consider alternative protein sources for feed. Global population is expected to increase from 6 billion today to more than 7.5 billion by 2020. This burgeoning population may require a doubling of animal protein production and a corresponding doubling of feed grains (Persley, 2000). This is due in part to improved economic standards leading to increased demand for high-quality animal protein. A demand-driven livestock supply expansion will require dramatically improved livestock productivity on a global scale. To date, increasing meat, milk and egg production from a unit of land has been largely the result of improving crop yields. However, of growing importance, are changes in the types and quality of nutrients in specific crops and the impact these changes may have on the efficiency of the animal’s conversion of consumed feed to meat, milk and eggs.

This paper will consider four topic areas:

• First, alternative protein sources to make up the anticipated shortfall resulting from the MBM ban and longer-term population growth.

• Second, the promise of traditional plant breeding and agricultural biotechnology to address the protein shortfall by enhancing animal nutrition and/or health.

• Third, identity preservation of nutritionally enhanced crops for product delivery and value capture.

• Finally, a global strategy for the regulatory approval process of nutritionally enhanced biotech crops.

PROTEIN RAW MATERIALS FOR USE IN FEED
Meat and bone meal: leading up to the ban

MBM is a protein-rich powder derived from the rendering of animal tissues. In the past, adding animal by-products to feed served three purposes:

1. MBM was a cost-effective way to increase the levels of protein and/or minerals in animal diets.

2. It complemented protein from grain ingredients to improve dietary protein quality.

3. MBM provided a good use for rendered by-products, reducing waste and disposal problems.

Rendered by-products were previously considered safe, because the high temperatures used in processing were known to kill microbes. However, that thinking was re-examined after the first case of BSE was diagnosed in the United Kingdom in 1986. By December 1997, ruminant MBM in feed was identified as the most likely cause (European Union On-Line, 1998).

Scientists are just beginning to fully understand what causes BSE in cattle, and its possible relationship to the new variant that causes Creutzfeldt Jakob Disease (vCJD) in humans. BSE and vCJD are both among the group of animal and human diseases known as transmissible spongiform encephalopathies (TSEs). TSEs are characterized by a sponge-like appearance of the brain and associated with deposits in the brain of unique proteins called prions. Prions, which have only recently been discovered, are unique proteins with a novel mode of replication and transmission. The prion is not a complete living organism, but a polypeptide that may bind to DNA in the central nervous system. It does not replicate in the same way as DNA-containing organisms such as bacteria and viruses, and has been shown to be very resistant to many of the methods, such as high processing temperatures, that have traditionally been used to destroy pathogenic agents.

It is widely believed that cattle contracted BSE from consuming feed containing animal by-products contaminated with prions. BSE may have originated from cattle feed containing MBM derived from sheep infected with scrapie (a TSE in sheep and goats, similar to BSE in cows). Strong agreement exists that the original outbreak of BSE in Europe was amplified by feeding MBM prepared from BSE-infected cattle to calves (United States Food and Drug Administration 2001a).

The Office International des Epizooties (2002) reports that BSE has been confirmed in some 20 countries. More than 180 000 cases have been confirmed in the United Kingdom and about 1 800 cases have been found elsewhere in Europe, with Portugal, France, Switzerland, Germany and Spain, respectively, having the highest incident rates (Office International des Epizooties, 2002; United States Food and Drug Administration, 2001b). Consequently, the United Kingdom introduced a ban on feeding ruminant-derived MBM to cattle in July 1988. The ban was extended to all animal feed in September 1990. The European Union has prohibited the feeding of mammalian protein to ruminants since 1994 (European Union On-Line, 1998). The European Union ban was extended to feed rations for all other livestock in January 2001 (Brookes, 2001). Although temporary, the extended ban (or substantial parts of it) could become permanent. The current European Union-wide controls apply not only to meat and bone meal, but also to other sources of animal protein (e.g., blood meal, dried plasma, hoof meal, feather meal, etc.). Although beyond the scope of this paper, the ban also raises the issue of how animal protein, which was previously rendered into MBM, will be properly and cost effectively disposed.

The first BSE case confirmed outside Europe was in September 2001, when a farm near Tokyo reported that one of its Holsteins tested positive for the disease. To date, three cases have been confirmed in Japan (World Organization for Animal Health, 2002). The Japanese government reacted by banning ruminant MBM use in cattle feed in September 2001 and extended the ban to all other livestock feed in October of that year. However, meat and bone meal made of pigs’ blood and chicken meat and feathers were exempt from Japan’s overall MBM ban.

Soy meal: the preferred protein alternative

Soy meal, a residual product of the oil extraction process from soybeans, is the most used and preferred protein source in animal feed worldwide. This is due to its relatively high protein content of 44 to 50 percent, its consistent availability and constantly competitive price (Brookes, 2000, 2001).

World production in protein-rich substances (primarily soybeans) increased by 60 percent between 1985 and 2000, with soybean supply currently concentrated in the United States, Brazil and Argentina (European Parliament, 2001). The International Service for the Acquisition of Agri-biotech Applications (James, 2001) reports that 72 million hectares of soybeans were planted globally in 2001, with 46 percent planted to biotech varieties. The abundant availability of competitively priced soybeans and soy meal on world markets today, should be able to replace the protein material formerly derived from MBM in the European Union (EU) and elsewhere, without undue difficulty and only at a modest addition to compound feed costs (Brookes, 2001).

Soy meal dominates as a protein source in the EU feed sector, accounting for 53 percent of the total protein supplement used, with only 3 percent of the soy meal derived from EU supply sources (Brookes, 2001). The Commission of the European Communities (2001) has predicted that the EU livestock industry would react to the MBM ban by:

• Reducing the use of protein-rich feed ingredients to a level that is consistent with reasonable levels of technical efficiency and that would not have a significant negative impact on factors such as feed conversion rates.

• Increasing the use of cereals in animal feed and meeting any remaining deficit through the importation of soy meal. For Europe to produce substantially more vegetable protein material, EU farmers would require the necessary market and policy incentives. The current farm-level profit margins derived from soybeans are significantly lower than those of other oilseeds and cereals. Also, the EU is in the process of implementing the Agenda 2000 policy reforms, which further reinforce the existing financial advantages of growing cereal crops. As such, current market and policy incentives are inadequate to increase soybean production in the EU by any significant amount (Brookes, 2001).

One year after the extended EU ban on the use of MBM began; the EU has largely replaced the loss of MBM by using additional volumes of soy meal, the vast majority of which has been imported. Early estimates of trade statistics for the year 2001 suggest that the EU imported an additional 1 to 1.5 million tonnes of soybean meal relative to 2000 (G. Brookes, personal communication, 2002). Other sources of protein-rich ingredients also have contributed somewhat to meeting the MBM shortfall (e.g., other oilseeds like canola). However, other common EU protein sources have limits on their usage in the diet due to amino acid imbalances or anti-nutrients as compared to soy meal, which has nearly no limitation to its inclusion in animal feeds. Soy meal has been the main replacement ingredient because of its inherent technical qualities and competitive price (in protein equivalent terms) relative to alternatives.

Other protein-rich crop alternatives
The European Parliament has investigated options for increasing the supply of alternative protein-rich crops, including oilseeds (e.g., peas, beans, sweet lupins). The Commission of the European Communities (2001) analyzed options for increasing production, including aid incentives to EU farmers and easing restrictions on set-aside land. The Commission concluded that production incentives would satisfy additional protein needs only to a very limited extent. For example, increased aid to stimulate an increase in the area cultivated with oilseeds and protein crops would be relatively costly, with only modest production increases predicted and being explained by (expected) favourable cereal price developments. This option, in particular, would lead to relatively high additional expenditures and opportunity costs compared to the current import price for soy meal.

The next section will consider how traditional plant breeding and agricultural biotechnology have addressed, and will continue to address, the protein shortfall and the improvement of animal nutrition.

IMPROVING ANIMAL PERFORMANCE AND HEALTH WITH NUTRITIONALLY ENHANCED CROPS

An important objective of agricultural biotechnology is to improve plant quality to benefit the health, growth and/or nutrition of animals. By way of this technology, crops commonly used in animal feeds can be enhanced so they better match the nutritional needs of specific livestock and poultry. This should reduce feed costs, making meat protein more affordable in many parts of the world, and reduce dependency on MBM to add needed protein to animal diets. Nutritionally enhanced crops also should reduce the environmental impact of livestock production (e.g., by reducing phosphorus, nitrogen, methane, etc., concentrations in animal waste). This section will address the major crops used in livestock feed today, and examine how these crops could be improved to enhance animal nutrition.

Global usage of crops in feed

The FAO Statistical Database (FAO, 2002a) shows that the top commodities used in animal feed worldwide are maize, soybeans, wheat and barley, respectively. Cereals such as maize and wheat account for about half of all feed ingredients, primarily because they are good sources of energy. Maize tends to be the preferred feed grain because it is rich in highly digestible carbohydrates and relatively low in fibre, which is particularly important for swine and poultry. Because of its relatively low protein levels (7 to 9 percent), maize generally requires supplementation with protein-rich feeds and amino acids (e.g., lysine and methionine) in diets for pigs and poultry. Young ruminants also may require protein supplementation with attention to dietary protein quality (FAO, 2002b).

Oilmeals (such as soy meal) are the second most important group of feed ingredients as protein sources. As mentioned earlier, soy meal is one of the most valuable sources of vegetable protein. The amino acid composition in soy meal is nearly comparable to that of milk protein and complementary to the amino acid profile of maize. Although it is a good source of some vitamins, soy meal lacks vitamin B₁₂, which must be supplemented, particularly in poultry diets (FAO, 2002b).

The promise of nutritionally enhanced crops

The first generation of biotech crops contain agronomic traits that create value by providing plants with the ability to increase production or reduce the need for other inputs such as pesticides. One example is Bt insect-protected maize, which already is improving feed quality and animal health by reducing fungal infection and mycotoxin contamination associated with insect feeding damage.

What is on the horizon? An article in Science (Mazur et al., 1999) reports that the composition of oils, proteins and carbohydrates in maize, soybeans and other crops is being modified to produce grains with enhanced value for both animal feeds and food for human consumption. Both traditional plant breeding and biotechnology techniques are being used to produce plants carrying the desired quality traits. The next commercial wave of nutritionally enhanced crops will focus on improved feeding value related to protein quality (better balance of essential amino acids), digestibility (fibre and starch) and metabolizable energy (oil). Nutritionally enhanced feedstuffs also can address anti-nutrients (e.g., phytate, protease inhibitors and tannins) that affect digestibility and feed value.

Current biotech examples include rice with pro-vitamin A (Ye et al., 2000), high-lysine maize (O’Quinn et al., 2000), high-lysine canola and soybeans (Falco et al., 1995) and high-oleic acid soybeans (DuPont, 1996). These products often achieve their nutritional or health benefits through modifications to the plant’s metabolism.

The following are examples of nutritionally enhanced crops improved through traditional plant breeding and/or biotechnology with direct benefits to animal production. As indicated below, some of these have been successfully commercialized.

1. Low-phytate soybeans and maize. Phosphate naturally present in traditional varieties of soybeans and maize exists primarily in the form of an insoluble salt called phytate. Low-phytate crops can improve efficiency of phosphorus utilization in monogastric animals (e.g., swine and poultry). Monogastric animals lack the phytase enzyme needed for digestion of phytate (also known as inositol hexaphosphate). Thus, most of the maize and soy phytate is excreted by animals. In some circumstances, this contributes to water pollution problems due to release of phosphate in the environment. Because phytate is a strong chelating agent that binds certain ions such as zinc and iron, vitamins and minerals in low-phytate crops are more available to the animal and, therefore, more likely to be absorbed than excreted. Low-phytate maize was commercialized in the United States in 1999 (Wehrspann, 1998). Low-phytate soybeans have already been developed, but researchers are still working to achieve an acceptable yield before commercialization (Raboy et al., 1985).

2. Crops with higher levels of the amino acids such as methionine and lysine. The potential impact of high-methionine soybeans is important because it could eliminate the need for methionine as a feed supplement, particularly in poultry diets. Similarly, the value of high-lysine maize would be as a substitute for synthetic lysine in swine and poultry diets. Methionine and lysine are both essential amino acids for growth, and cereal grains are generally a poor source. Crops also could be enhanced to compensate for other low concentration essential amino acids such as tryptophan or isoleucine.

3. Low-fibre feedstuffs. Monogastric animals do not produce the enzymes necessary to digest cellulose-based plant fibre. Plants low in fibre should yield more digestible and metabolizable energy and protein, and less manure and methane when fed to simple stomached species (North Carolina Cooperative Extension Service, 2000). Improved fibre digestibility in ruminants will have similar beneficial effects because the efficiency of digestion of most high-fibre diets for ruminants is far from optimized.

4. High-oleic soybeans. High-oleic soybeans can contain more than 80 percent oleic acid in their oil, compared to 24 percent for traditional soybean oil (Payne, 1997). Because oleic acid has greater heat and oxidation resistance than other fatty acids in soybean oil, high-oleic soybean oil is naturally more resistant to degradation by heat and oxidation over time. It requires less or no hydrogenation, which would decrease trans-fatty acid production. In addition, this research has indicated that feeding high-oleic soy meal fullfat (i.e., containing the oil) to cows and chickens may result in a lowering of saturated fat levels in milk and poultry meat.

5. High-oil maize. High-oil maize has the potential to increase the flexibility of formulating feed rations due to its high energy density. Animals that consume high-oil maize will be provided with more vitamin E, as well as more energy. Vitamin E helps prevent cardiovascular disease, which is particularly relevant in chickens. Carcass fat of animals fed high-oil maize also has lower saturated fats and more unsaturated fatty acids (Lohrmann et al., 1998). The first high-oil maize product, developed using traditional breeding methods, was released in the United States in 1992 (Lin et al., 2000).

6. Low-stachyose (high-sucrose) soybeans. Stachyose, an oligosaccharide (carbohydrate), is non-digestible in humans and other monogastric animals (Suarez et al., 1999). Instead of being digested in the stomach, stachyose passes to the intestines where bacteria ferment it into gases. In low-stachyose soybeans, it is replaced with the easily digested sugar sucrose. Low-stachyose soybeans also are higher in energy content than traditional soybeans, making them doubly useful as an ingredient in young animal diets. Researchers found that the incorporation of low-stachyose soybean meal in prestarter pig diets tended to improve growth performance (Risley and Lohrmann, 1998).

7. Oligofructan-containing soybeans. These soybeans may be able to improve intestinal health by altering the composition of microflora in the digestive system (EBS forms business unit, 1999). Oligofructan components in soybeans can selectively increase the population of beneficial species of bacteria (e.g., bifidobacteria) in the intestines of certain animals, and competitively remove or ’crowd out’ harmful species of bacteria (e.g., E. coli 0157:H7, Salmonella SE, etc.). Thus, the soybeans may potentially displace some of the antibiotics historically used to combat diseases caused by bacteria. The oligofructan-containing soybeans also cause preferential growth of beneficial strains of bacteria that emit certain short-chain fatty acids. These are absorbed in the colon and result in a reduction in blood serum triglycerides (fat), which reduces the risk of heart disease.

8. Antibody-containing soybeans. These may improve meat quality and lessen the danger of E. coli outbreaks when meat is contaminated during slaughter and processing (Nill, 2001). Today’s periodic outbreaks of beef-borne bacterial disease occur because cattle became tolerant to E. coli 0157:H7 in the 1970s [it had previously killed the animals]. Humans occasionally are exposed to deadly bacteria when cattle digesta come into contact with meat (e.g., at slaughterhouses). It is now possible through biotechnology to cause specific antibodies to be produced in soybeans, so antibody-containing soybeans could potentially be fed to livestock for 72 hours prior to slaughter to reduce or even eliminate outbreaks of food-borne diseases such as E. coli 0157:H7 and Salmonella spp.

IDENTITY PRESERVATION OF NUTRITIONALLY ENHANCED CROPS FOR PRODUCT DELIVERY AND VALUE CAPTURE

Clearly, many new crops are in development that will create value by enhancing nutrient composition and/or improving animal health and performance. As a result, preservation of a nutritionally enhanced crop’s identity is important because the crop will be more nutritious or have different qualities compared to its traditional counterparts. It will be essential to keep the nutritionally enhanced crop separate to ensure its higher value is maintained from the farm to the end customer. The end customer may be a farmer feeding the nutritionally enhanced crop to his/her owns livestock, or a livestock feeder that has contracted for the crop to be produced in another region or country. A feed manufacturer may also wish to source an enhanced crop for its improved processing characteristics. Crops are processed to separate valuable components such as proteins and oils from less valuable components such as hulls. Nutritionally enhanced crops could be developed with higher levels of the more valuable components, or with improved nutritional quality of the lower value components.

For example, the added value from high-oil maize comes from reduced expenditures for fat supplements in the feed ration, as well as improved digestibility and feed efficiency. A United States farmer seeking to grow high-oil maize can identify interested local elevators (grain stores) through the Internet. The company that markets high-oil maize to farmers also ensures that it is segregated throughout the entire supply chain based on a network of contracts. The contracts coordinate the crop’s movement from farm to elevator to barge to ocean freight to end customers in Mexico, Japan or Taiwan (Lin et al., 2000).

Identity preservation (IDP) is more stringent than crop segregation, and requires that strict separation (often involving containerized shipping) of the seed and crop be maintained from field to point of sale (Lin et al., 2000). IDP programmes typically include the following components:

Thorough record-keeping and data entry by growers and processors associated with each contract. This should include in-field data collection technology to record quality testing and agronomic management data.

Complete and accurate databases that are easily accessible and user-friendly. Data should be immediately available, through the Internet, for example.

Field-oriented, unbiased audits of all critical process points outlined in each production contract (Mock, 2000).

The payoff for maintaining the identity of a nutritionally enhanced crop comes in the form of price premiums to farmers and grain handlers, and improved animal health and reduced input costs for livestock producers. The next section provides a framework for the regulatory approval process for nutritionally enhanced biotech crops, as compared to the current process used for biotech crops with agronomic traits.

GLOBAL STRATEGY FOR A REGULATORY APPROVAL PROCESS FOR NUTRITIONALLY ENHANCED BIOTECH CROPS

The Organization for Economic Cooperation and Development (OECD) conducted a Workshop on the Nutritional Assessment of Novel Foods and Feeds in 2001. Specifically, the workshop examined the question of what would be the most appropriate process for the nutritional and safety assessment of nutritionally enhanced biotech products.

The workshop recommended that a comparative safety assessment currently provides the best scientific process for assuring the safety and nutrition of foods and feeds from nutritionally enhanced biotech products. Table 1 compares the food and feed safety and nutritional studies appropriate for both agronomic and nutritionally enhanced biotech products. The safety assessments previously used for agronomic traits - such as insect-protected maize and herbicide-tolerant soybeans - remain a good model for nutritionally enhanced biotech traits. Many of the studies, such as protein safety, molecular and phenotypic or agronomic characterization, are largely appropriate without modification for nutritionally enhanced biotech products. Other studies may need refinements to accommodate differences between agronomic biotech products such as insect-protected maize (e.g., many of the non-target organism studies are irrelevant) and nutritionally enhanced biotech products (e.g., the possible need for additional compositional analyses and the possible utility of a nutritional feeding study with a fast-growing animal species).

The elements of the nutritional and safety assessment should follow a logical progression starting with morphological, agronomic and physiological analyses of the plant, to assess whether unanticipated metabolic changes have altered the plant itself. Detailed compositional analyses of nutrients, anti-nutrients and relevant secondary metabolites should follow. The last stage would be to assess, on a case-by-case basis, whether in vitro tests, animal studies or human clinical studies are needed, depending upon the specific nutritional or health trait being developed and the claims being made.

TABLE 1
Food and feed safety and nutritional studies appropriate for agronomic and nutritionally enhanced biotech products

Molecular characterization

Regardless of whether a biotech product expresses an agronomic or nutritional trait, the studies needed to characterize inserted DNA resulting from the transformation process, would remain the same. The molecular characterization of any agronomic or nutritionally enhanced biotech product should involve assessing: insert number, copy number, integrity of the inserted transgenic DNA elements, and the presence or absence of vector backbone sequences.

Protein safety assessment

Regardless of whether the biotech crop is an agronomic or nutritionally enhanced product, in most cases the safety assessment of the introduced protein can use the same set of studies, such as for the Cry1Ab protein introduced into insect-protected maize (MON810). These studies assess the level of the novel protein in the feed grain and food; determine the rate of degradation in simulated gastric fluids; and confirm lack of similarity to known allergens and toxins. In addition, these studies also establish the no adverse effect level (NOAEL) in acute animal oral toxicity experiments with the purified protein. Also critical to a safety assessment of a novel introduced protein is the history of safe use of the donor organism from which the gene for the novel protein was isolated.

Composition/Nutrition assessment

The modifications to plant metabolism needed to produce nutritionally enhanced biotech crops may result in qualitative and/or quantitative differences in composition when compared to conventional crop varieties. The widely used comparative safety assessment process involves identifying the similarities and differences (e.g., nutrients, anti-nutrients, primary and secondary metabolites) between a biotech crop and the traditional counterpart, then subjecting the significant identified differences to a rigorous safety evaluation. This comparative process can be used for the safety assessment of nutritionally enhanced biotech crops as well. In some cases, new analytical methods may be required to thoroughly identify and quantify significant compositional differences between nutritionally enhanced biotech crops and their traditional counterparts. To be successful in using the comparative safety assessment process with nutritionally enhanced biotech crops, the scientific methods must be rigorously validated.

Modifications to plant metabolism needed to achieve the intended nutrition and health benefits of nutritionally enhanced biotech products may result in qualitative and/or quantitative differences that may be difficult to detect, even by the most sophisticated compositional profiling technologies. As a result, it was recommended that a feeding study with a single, fast-growing species, such as the broiler chicken, should be included in a nutrition assessment to detect unexpected effects not captured by chemical analyses or other laboratory measurement techniques. A fast-growing species was recommended because its growth rate is so highly optimized that relatively subtle changes in nutrients or anti-nutrients become readily apparent during growth performance trials.

Summary

As the world’s population continues to rapidly grow and governments work to extend the MBM ban to the feeding of all animals, the feed industry must look for alternative protein sources to feed the increasing number of humans, as well as to replace the protein material formerly derived from MBM and fed to animals. Under current conditions, soy meal seems to be the best alternative. The abundant availability of competitively priced soybeans and soy meal on world markets today should be able to replace the protein material without undue difficulty (Brookes, 2001).

Nutritionally enhanced crops - developed using both traditional plant breeding and biotechnology techniques - hold potential for improving animal performance, reducing feed costs, making meat protein more affordable in many parts of the world, and reducing dependency on MBM to add needed protein to animal diets. Such crops would benefit the health, growth, performance and/or nutrition of animals. It will be essential to preserve the identity of nutritionally enhanced crops from the farm to the end customer in order to capture the crops’ higher value.

If the feed industry is to benefit from nutritionally enhanced biotech crops, a global strategy is needed for the approval process. As recommended by the OECD Workshop on the Nutritional Assessment of Novel Foods and Feeds in 2001, the safety assessments previously used for agronomic traits remain a good model for nutritionally enhanced biotech traits. Many of the studies are largely appropriate without modification for nutritionally enhanced biotech products, while other studies may need refinements to accommodate differences between agronomic and nutritionally enhanced biotech crops.

REFERENCES

Brookes, G. 2001. The EU animal feed sector: Protein ingredient use and the implications of the ban on use of meat and bonemeal. Canterbury, UK, Brookes West.

Brookes, G. 2000. GM and non GM ingredient market dynamics and implications for the feed industry. In Proceedings of the 6^th International Feed Production Conference, p. 308-314.

Commission of the European Communities. 2001. Options to promote the cultivation of plant proteins in the EU. Brussels, Belgium.

DuPont Agricultural Products. 1996. Safety assessment of high oleic acid transgenic soybeans. Notification dossier 62 FR 9155-9156, Docket No. 96-098-1.

EBS forms nutrition unit. 1999. Feedstuffs, 71(33),: 15.

European Parliament, Committee on Agriculture and Rural Development. 2001. Working report on options to promote the cultivation of plant proteins in the European Union.

European Union On-Line. 1998. Special Report No. 19/98 concerning the Community financing of certain measures taken as a result of the BSE crisis, accompanied by the replies of the Commission. (available at http://europa.eu.int/eur-lex/en/lif/dat/1998/en_398Y1209_01.html).

Falco, S., Guida, T., Locke, M., Mauvais, J., Saunders, C., Ward T. & Weber, P. 1995. Transgenic canola and soybean seeds with increased lysine. Bio/Technology, 13: 577-582.

Flachowsky, G. & Aurlich, K. 2001. Role of nutritional assessment of GMO in feed safety assessment. Paper presented at the OECD Workshop on the Nutritional Assessment of Novel Foods and Feeds, Ottawa, Canada.

Food and Agriculture Organization. 2001. BSE - More than 30 countries have taken action on BSE, but more needs to be done. [Press release, June 21].

Food and Agriculture Organization. 2002a. Food and Agriculture Organization Statistical Database. (available at http://apps.fao.org/page/collections?subset=agriculture).

Food and Agriculture Organization. 2002b. Animal Feed Resources Information System. (available at http://www.fao.org/ag/AGA/AGAP/FRG/afris/default.htm).

Institute of Food Technologists. 2001. Bovine spongiform encephalopathy: A backgrounder of the Institute of Food Technologists. February.

International Food Information Council. 2001. BSE response plan. Washington, D.C. September.

James, C. 2001. Global review of commercialized transgenic crops: 2001.

ISAAA Briefs No. 24: Preview. International Service for the Acquisition of Agri-biotech Applications: Ithaca, NY.

Lin, W., Chambers, W. & Harwood, J. 2000. Biotechnology: US grain handlers look ahead. Agricultural Outlook, April. Economic Research Service, USDA.

Lohrmann, T. T., Hahn, J. D. & Araba, M. 1998. Effect of Optimum® high oil corn as a replacement for typical corn and choice white grease in finishing pig diets. Journal of Animal Science, 76(Suppl. 2).

Mazur, B., Krebbers, E. & Tingey, S. 1999. Gene discovery and product development for grain quality traits. Science, 285: 372.

Mock, J. J. 2000. Tracing the integrity of agricultural products from field to food. ASA Technical Bulletins.

Nill, K. 2001. A codex standard mandating “GMO labeling” of food products containing genetically modified ingredients would decrease global food safety. American Soybean Association, March 9.

North Carolina Cooperative Extension Service. 2000. Genetically modified organisms in animal production. Swine News, 23(5).

Office International des Epizooties. 2002. Number of reported cases of bovine spongiform encephalopathy (BSE) worldwide. (available at http://www.oie.int/eng/info/en_esbmonde.htm).

O’Quinn, P., Nelssen, J., Goodband, R., Knabe, D., Woodworth, J., Tokach, M. & Lohrmann, T. 2000. Nutritional value of a genetically improved high-lysine, high-oil corn for young pigs. Journal of Animal Science, 78: 2144-2149.

Payne, J. H. 1997. DuPont petition 97-008-01p for determination of nonregulated status for transgenic high oleic acid soybean sublines G94-1, G94-19, and G-168: Environmental assessment and finding of no significant impact. Riverdale, MD, USA, Department of Agriculture, Animal and Plant Health Inspection Service, Biotechnology and Scientific Services.

Persley, G. J. 2000. Agricultural biotechnology and the poor: Promethean science. Consultative Group on International Agricultural Research.

Raboy, V., Hudson, S. J. & Dickson, D. B. 1985. Reduced phytic acid content does not have an adverse effect on germination of soybean seeds. Plant Physiology, 79: 323-325.

Risley, C. R. & Lohrmann, T. T. 1998. Growth performance and apparent digestibility of weanling pigs fed diets containing low stachyose soybean meal. Journal of Animal Science, 76(Suppl. 1).

Suarez, F. L., Springfield, J., Furne, J. K., Lohrmann, T. T., Kerr, P. S. & Levitt, M. D. 1999. Gas production in humans ingesting a soybean protein derived from beans naturally low in oligosaccharides. American Journal of Clinical Nutrition, 69: 135-139.

United States Food and Drug Administration. 2001a. BSE: Background, current concerns, and United States response. March 1.

United States. Food and Drug Administration. 2001b. Food and Drug Administration action plan: Transmissible spongiform encephalopathies. April 24.

Wehrspann, J. 1998. New traits of seed buying. Farm Industry News, 31(10).

Ye, X., Al-Babili, S., Klotl, A., Zhang, J., Lucca, P., Beyer, P. & Potrykus, I. 2000. Engineering the provitamin A (b-carotene) biosynthetic pathway into (carotenoid-free) rice endosperm. Science, 287: 303-305.