A growing consensus is forming around the prediction that the global human population will reach nearly 10 billion people by 2050 (FAO, 2009a). Providing adequate and nutritious food for such a large population highlights the importance of the world’s agriculture system. Indeed, the Food and Agricultural Organization of the United Nations (FAO) projects that food production will have to increase by 70 percent over the same time frame (FAO, 2009a). Note that as with any prediction, there are numerous underlying assumptions and uncertainties associated with the reported number; however, it is almost certain that there will be a need for global food production to increase substantially in the foreseeable future. Projected increases in income globally will increase demands for not only more food but for better quality food, leading to an increased intake of animal protein (FAO, 2009a; Masuda and Goldsmith, 2010). The demand for more high-quality foods will have to be met by increases derived from plant and animal production systems.
As a result, animal agriculture in the 21st century faces increasing and persistent challenges to produce more animal protein products in the context of an emerging, globally complex set of conditions for sustainable animal production. This, in turn, requires the rethinking of the very nature of animal science. In addition to the increasing demand for animal products in the context of globalization of food systems, these challenges include, but are not limited to, consequences for individual country and regional concerns about food security, such as the impact of
geopolitical strife on food production and distribution, the intensification of production systems in the context of societal and environmental impacts, the development and maintenance of sustainable animal production systems in the face of global environmental change, and the multidecadal decrease in public funding in real dollars for animal science in the United States and variable funding worldwide.
These challenges point to the need for animal science research that improves the integration among its disciplinary components, including food science and the socioeconomic and environmental sciences with which these various challenges overlap. A new roadmap for animal science research is required that focuses on animal production but intimately informs and is informed by the broader socioeconomic and environmental conditions of the new century. Thus, animal agriculture and animal protein production must substantially increase in production and efficiency, but in the context of sustainability. Interestingly, agriculture, and particularly crop production, has before faced similar questions related to global production and efficiency. The outcome for that challenge in the 1960s was predicated on the genetic improvement in major crop staples, often referred to as the Green Revolution (IFPRI, 2002). As a result, cereal production in Asia more than doubled between 1970 and 1995 (IFPRI, 2002). The environmental and socioeconomic consequences of that effort are still being debated (IFPRI, 2002), given the high input demands for hybrid crops and the difficulty that marginal, smallholder farmers have in participating in their production. Today’s agricultural researchers and practitioners can learn from the successes and mistakes of the Green Revolution to design and conduct even more successful research that optimizes animal protein production while minimizing environmental, social, and economic impacts. This is the principal challenge for today’s researchers and policy makers.
Agricultural research has made significant strides in the last century regarding productivity in the United States. Farm efficiencies, including animal production, have improved. For example, a fourfold increase in milk yield per cow was obtained between 1944 and 2007. The dairy milk industry has achieved a 59 percent increase in total milk production (53 billion kg in 1944 vs. 84 billion kg in 2007) while also decreasing the national dairy herd from 25.6 to 9.2 million cattle (Capper et al., 2009).
Similarly, beef cattle productivity increased significantly between 1977 and 2007. The average slaughter weight (607 kg in 2007 vs. 468 kg in 1977) and growth rate (1.18 kg/day in 2007 vs. 0.72 kg/day in 1977) resulted in the total average days from birth to slaughter being reduced from 609 days (1977) to 485 days (2007) (Capper, 2013). The pork industry increased the number of hogs marketed from 87.6 million in 1959 to 112.6 million in 2009 from a breeding herd that decreased in size by 39 percent over the same time period (Cady et al., 2013). In the last 50 years, the poultry industry has made tremendous progress. According to Ferket (2010), in 1957, a 42-day-old broiler weighed 540 g with a feed conversion rate (FCR) of 2.35. In 2010, a broiler of the same age weighed 2.8 kg with an FCR under 1.70. Not only has the growth performance of broilers improved significantly during the past 50 years, but also its conformational structure has changed. Similar changes have occurred in turkeys. In 1966, an 18-week-old turkey tom weighed about 8 kg with an FCR of 3.0. in 2010, a tom of the same age could weigh over 19 kg with an FCR under 2.55. Layer performance has also changed significantly from 1958 until the present day. Over the past 50 years, egg production per hen has increased over 64 percent, egg mass per hen by 83 percent, and the amount of feed consumed per gram of egg produced decreased by over 20 percent (Ferket, 2010). Crop yields, some of which serve animal agriculture, have undergone similar increases. Average corn yields increased from approximately 1.6 tons/ha in the first third of the 20th century to approximately 9.5 tons/ha in 2009 (Edgerton, 2009). Aquaculture production increased 12 percent in volume and 19 percent in value from 1998 to 2008, principally from the shellfish sector, which includes mollusks and crustaceans (Olin, 2012).
Outside of a few intensive production systems, the developing world has not witnessed similar growth in animal agricultural productivity across its many sectors. Productivity in developing countries, particularly sub-Saharan Africa and parts of Southeast Asia, is far below world averages and too low to support expanding local demand (Sanchez, 2010). Agriculture in the developing world faces inadequate inputs and infrastructure, insufficient agricultural research focused on local environmental concerns, and competition from specialized commercial production destined for distant markets (Sanchez et al., 2007). Although technologies that may be of value to animal agriculturalists in developing countries exist or are under development, low levels of use have resulted in a wide yield gap (Table 2-1; NRC, 2009). The exception is aquaculture, where gains have been made and now constitutes 49 percent
of the entire amount of seafood (excluding plants) consumed in the world and is expected to reach 62 percent by 2030 (FAO, 2014b). Commercial aquaculture production increased from 4.8 to 66.6 million tons between 1980 and 2012, a 13.9-fold increase (FAO, 2014b). As a result of these and other gains, the food supply in the United States and many other parts of the world has been affordable and abundant. The volume of global aquaculture production has risen dramatically since the 1970s, largely due to productivity growth facilitated by improved research and development (R&D), input factors, and technical efficiency in aquaculture farming (Asche, 2013).
TABLE 2-1 Average Animal Product Output in 2007 (kg of meat or milk per animal)
|Country||Beef & Buffalo||Poultry Meat||Goat||Cattle Milk|
SOURCE: Gapminder (http://www.gapminder.org).
Responding to a perceived crisis in U.S. agriculture and recognizing that continued innovation is key to meeting this crisis, the U.S. 2004 Danforth Task Force recommended that the U.S. Department of Agriculture (USDA) create two new programs: the National Institute of Food and Agriculture (NIFA), subsequently created by the Food, Conservation and Energy Act of 2008, and the Agriculture and Food Research Initiative (AFRI). NIFA, mirroring earlier recommendations of the USDA, proposed a de-emphasis on agricultural research on productivity, efficiency, and innovation, and the creation of activities on renewable energy, obesity, human disease prevention of zoonotic disease (e.g., avian influenza), and environmental impact of agriculture.
Internationally funded research in the developing world focuses on improved productivity or public health considerations (e.g., zoonotic issues). Examples of agencies that fund international research are the World Bank, United Nations Development Programme, U.S. Agency for
International Development, Rockefeller Foundation, and Bill & Melinda Gates Foundation. The majority of this funding is through financial assistance, donations, and loans, and focuses on production and social well-being, which includes translational research (research to application) and education and training activities.
The direction of international research indicates correctly that sustainable animal agriculture is intertwined with food security (NRC, 2012). As defined by the 1996 World Food Summit, food security refers to conditions in which “all people, at all times, have physical and economic access to sufficient, safe, and nutritious food to meet their dietary needs and food preferences for an active and healthy life” (FAO, 1996). Addressing food security requires the consideration of factors other than production, such as access to food (i.e., entitlements), as part of meeting sustainable animal production goals. After all, famine and malnutrition, including “food deserts” in the United States, have long occurred and continue to persist in the midst of plentiful food (Sen, 1983; Baro and Deubel, 2006). Concerns about the prevalence of food deserts prompted a 2009 Institute of Medicine workshop exploring the negative public health effects of food deserts in low-income areas in the United States (IOM and NRC, 2009). Improving entitlements, which falls beyond the research domain of animal agriculture, would help to ameliorate food security problems in 2050, but does not eliminate the need for significant advances in sustainable production.
Today’s research must carefully consider environmental, health and disease, sociocultural considerations, community welfare, animal welfare, economic and policy constraints and other factors. The needs for current and future global food security cannot be met without greater emphasis and expansion of R&D devoted to productivity, efficiencies, and innovation in animal agriculture. The challenges of meeting these sustainability goals are massive and far beyond the domain of corporate interests. The committee agrees with the conclusion of the 2004 Danforth report that publicly sponsored research is essential to continued agricultural innovation.
Global Environmental Change
Global environmental change refers to the totality of changes, both natural and anthropogenic in origin, under way in the earth system from
ecosystems to climate change. Animal agriculture affects this change through the landscapes it consumes and the biogeochemical cycles it affects, and is also affected by these changes, in some cases significantly, and must adapt to them in order to provide the quantity and affordability of animal protein expected by society. This adaptation, in turn, has important implications for sustainable production.
Approximately 17 billion food animals globally occupy 30 percent of the ice-free land surface of Earth, resulting in about 72 percent of deforestation worldwide and consuming 32 percent of freshwater globally (Reid et al., 2008; FAO, 2009b; Nepstad et al., 2011). Currently, food animals contribute 14.5 percent of global greenhouse gas (GHG) emissions, according to the FAO (Gerber et al., 2013). Enteric fermentation from ruminants is the second largest global source of methane (Makkar and Vercoe, 2007). Land degradation from overgrazing rangelands has long been noted across many different socioeconomic and environmental conditions, leading to soil erosion and soil nutrient loss, reduced feed stocks, and habitat changes, among other impacts (Havstad et al., 2007; Jun Li et al., 2007). The impacts of some aquaculture practices have negatively affected wild fish stocks, prompting development of certification programs to help ameliorate such impacts (Naylor et al., 1998). These are only a few of the environmental consequences of animal agriculture (Wirsenius, 2003; Steinfeld et al., 2006a; Galloway et al., 2010), which also include environmental tradeoffs between land or water use for animal agricultural and nonagricultural purposes (e.g., urbanization and conservation), preservation, and maintenance of biotic diversity and functioning ecosystems and landscapes (Reid et al., 2008). Animal agriculture is increasingly confronted by these and other environmental issues.
By the end of this century, the global average temperature is likely to increase by between 2.6 and 4.8°C (NAS and RS, 2014). Significant temperature increases and rising drought are projected for much of the global land acres currently devoted to food animal production and crops used to support production worldwide (Parry et al., 2007; Thornton et al., 2009; Meehl et al., 2013). Overall, global climate change occurring in tandem with land-use changes raises a series of water and feed availability and quality problems for animal agriculture. Among these are the tradeoffs on environmental (ecosystem) services at large due to water and land demands of various systems of meat, egg, and milk production (Herrero et al., 2009; Thornton, 2010). For aquaculture, freshwater systems will be subject to many of the changes anticipated for terrestrial
systems such as flood, drought, and water availability. Marine-based systems will be subject to changes in sea surface temperatures, ocean acidification, and other related marine environmental variables, such as wind velocity, currents, and wave action (Handisyde et al., 2006). These changes will impact all types of animal agricultural production systems as well as the livelihoods of the communities they support.
The exact impact on food animal production and the future of animal agriculture as a whole are still the subjects of debate (Thornton, 2010). Some contend that by 2050, food animal production will reach or exceed certain environmental thresholds (Pelletier and Tyedmers, 2010). However, it is also contended that food animal production can be increased while attenuating environmental impact (Steinfeld and Gerber, 2010), possibly as a result of agricultural land use reaching a peak due to more land-efficient production processes (Ausubel et al., 2012). It is also believed that policies can be effective in decreasing meat consumption (Myers, 2014) among groups whose current consumption levels are high. Animal science research funding is needed because the true outcomes of these factors will reflect the capacity of animal agriculture to incorporate variation in geographic location and production types to adapt to global environmental change. The FAO, for example, found significant regional variation in GHG emission intensities from dairy, ranging from 1.3 CO2-eq/kg FPCM (fat- and protein-corrected milk) in North America (average milk yield of 8,900 kg/year) to 7.5 kg CO2-eq/kg FPCM in sub-Saharan Africa (average milk yield of 300 kg/year) (FAO, 2010). Hall et al. (2011) found that within a single aquaculture species group globally, impacts could vary by 50 percent or more. Adaptive capacities for much of sub-Saharan Africa and Southeast Asia are especially problematic for land-based systems of production, such as crop production (Parry et al., 2007; Lobell et al., 2008; Thornton et al., 2009), although environmental problems encountered in these areas attributable to climate change will be experienced throughout tropical regions globally (Parry et al., 2004; Morton, 2007; Thornton et al., 2009). These problems include negative consequences of climate warming for the quantity and quality of feeds owing to lower herbage growth, pasture compositional changes, increasing drought, and nitrogen leaching from the increased intensity of rainfall; increasing animal heat stress; reduction in water availability; and changing pest and disease vector challenges. In contrast, increased length of the growing season may favor food animal production at higher latitudes (Baker et al., 1993; FAO, 2007). Freshwater and marine-based aquaculture at temperate latitudes would probably decrease substantially
due to detrimental physiological demands caused by increases in water temperatures from climate warming.
The goal of reducing animal agriculture’s ecological footprint in the face of increasing production has progressively gained more attention (Clay, 2009; Chicago Council on Global Affairs, 2013). How this goal might be achieved will vary by the type of production system; systems vary from high to low input (intensive to extensive) in terms of the amount of capital and technological input needed, output per unit area, and time required to manage animals (Bertrand, 2014). Thorough analysis is necessary before viewing any production system as more or less sustainable, given the many environmental (ecosystem) services, species types, and social and livelihood implications. Generally, however, intensive systems for feed and animal production tend to produce fewer emissions and use less land per unit of production (Burney et al., 2010; O’Mara, 2011; Herrero et al., 2013). For example, the U.S. dairy industry has reduced feed use by 77 percent, land use by 90 percent, and water use by 65 percent and has achieved a 63 percent decrease in GHG emissions per kilogram of milk (Capper et al., 2009). The U.S. beef industry has reduced feed (19 percent), land use (33 percent), water use (12 percent) and GHG emissions (16 percent) per kilogram of beef over the referenced 30-year time period (Capper, 2011). The U.S. pork industry has achieved similar improvements, reducing water use by 41 percent, land use by 78 percent, and GHG emissions by 35 percent per pound of meat (Boyd and Roger, 2012). Similarly, the environmental footprint of the U.S. egg industry per kilogram of eggs produced is 65 percent lower in acidifying emissions, 71 percent lower in eutrophying emissions, 71 percent lower in GHG emissions, and 31 percent lower in cumulative energy demand than in 1960 (Pelletier et al., 2014).
In extensive animal agriculture, on the other hand, high constraints to capital and technology, as well as production goals that often differ from those in the commercial sector (Netting, 1993), results in lower production and, in some cases, increases footprint measures, such as land area per food animal head (Capper 2013; Herrero et al., 2013). Various assessments for such systems in Africa envision shifts in food animal portfolios (e.g., cattle to sheep and goats or the reverse) to offset projected climate change impacts on livelihoods (Seo and Mendelsohn, 2008), although quantification of the environmental consequences of these shifts has received minimal research attention. In 2008, 39 percent of all aquaculture was extensive, 42 percent was semi-intensive, and 20
percent was intensive (based on the weight of harvested fish). It has been projected that the available food needs for a global population of 9.2 billion people in 2050 will require a slightly greater than 100 percent increase in aquaculture production from 67 to 140 tonnes. This need can only be accomplished through the transition from extensive to semi-intensive systems and some semi-intensive systems to intensive systems (Waite et al., 2014).
Overall, the data demonstrate that intensive food animal systems reduce resource use, waste output, and GHG emissions per unit of food compared to extensive systems. This observation, however, has a major caveat. Although intensive systems allow for more efficiencies and often enhance the local economy and increase employment, they may have greater effects on local air, water, and land quality, especially where such systems cluster locationally (Atkinson and Watson, 1996; Eghball et al., 1997; Monaghan et al., 2005). The environmental impacts resulting from mismanagement of wastes include, among others, excess nutrients, such as nitrogen and phosphorus in water, which can contribute to low levels of dissolved oxygen. Other examples include detrimental effects on water quality from the runoff from confinement consolidation and intensification production. These concerns highlight the importance of proper management, location, and permitting and monitoring, which can reduce, minimize, or eliminate these impacts (Hribar, 2010; EPA, 2014). Although these footprint metrics for high-input systems have decreased substantially (Naylor et al., 2009), the overall magnitude of demand points to the need for sustained attention to the issues indicated by these metrics. The use of alternative feedstuffs, both plant and animal derived, continue to be assessed as viable production alternatives to help mitigate these environmental impacts. Various calculations indicate, however, that appropriate intensive animal production could yield significant environmental mitigation consequences for all agriculture globally (Herrero et al., 2009; Thornton and Herrero, 2010; Havlík et al., 2014). The movement from extensive to semi-intensive and intensive aquaculture production globally includes systems that employ recirculation of water yields, and could increase water-use efficiency in the aquaculture enterprise. This reduction also decreases the conflict of water use with other agricultural production systems. Addressing these impacts and lowering the ecological footprint of animal agriculture will increasingly become important because high-input animal agriculture in certain parts of the world can produce significant, detrimental
consequences elsewhere in the world for community livelihoods, food security, and access to resources, such as water (McLeod, 2011).
Health and Disease
Animal Health and Disease
Considerable challenges to the health and well-being of animals and humans are presented by animal disease pathogens. Understanding and developing effective measures to control animal infectious diseases are sometimes problematic mainly due to the lack of direct and continuous monitoring of the animal status as would otherwise occur with humans. The majority of these pathogens also have the ability to have a long period of carrier status in host animals (i.e., animals show no clinical signs but are able to transmit pathogens). For example, the bacterium Salmonella enterica may develop carrier status in an animal host, and such carriers typically excrete high levels of bacteria during recovery from enteric or systemic disease without showing clinical signs (Stevens et al., 2009). The carrier state may exist for the lifetime of the animal host with bacterial species such as S. enterica serovar Dublin. Therefore, preventive measures are critically important components of the first line of defense. There is a need for exploration and deployment of state-of-the art approaches for early diagnosis and surveillance to provide a network of global intelligence on their spread and an assessment of risk. The delivery of effective vaccine strategies for the control of major animal pathogens will be especially important, and finding new and better vaccines able to deliver long-lasting and durable protective immunity will be needed to be effective against multiple strains or variants.
One main goal of animal health is in food provision and food safety. During the last four decades, there have been several emerging and new health events that have received public attention. Most of these health events were linked to animal diseases or originated in animal products, including avian influenza, bovine spongiform encephalopathy, West Nile fever, sudden acute respiratory syndrome, HIV/AIDS, and Ebola virus. Because of the extensive involvement of animals and their products in these events, animal scientists and animal production sectors have been involved in measures to minimize the spread and impact of these diseases. The public health sector, particularly within central government or international agencies, has maintained the lead in the effort to control or eradicate these diseases. Nevertheless, the prevention effort requires
major involvement of animal health officers and others in related industries because the roots of most of these diseases extend to animal populations, particularly to food-producing animals (Salman, 2009).
The Agreement on the Application of Sanitary and Phytosanitary Measures (SPS Agreement) was finalized as part of the Uruguay Round of Multilateral Trade Negotiations General Agreement on Tariff and Trade (GATT, signed in Marrakesh in April 1994). Subsequent to its approval, the World Trade Organization (WTO) was established. The SPS Agreement’s main intent was to provide guidelines and provisions to member countries to facilitate trade while taking measures to protect human, animal, or plant life or health. The agreement advocates the use of international standards from the World Organization for Animal Health (OIE), the Codex Alimentarius, and the International Plant Protection Convention (IPPC) as the basis for recommended standards (Zepeda et al., 2001). It has become clear that the health status of animals and their products plays a major role in import and export regulations. This type of requirement for trade has placed pressure on the animal health structure both nationally and internationally. Animal scientists, particularly veterinary professionals, throughout the world are faced with having to fulfill a crucial role in protecting their country’s animal health status, providing sound surveillance information on the occurrence of diseases within their territories, and conducting scientifically valid risk analyses to establish justified import requirements (Salman, 2009). Population-based approaches for disease management require scientifically sound research prior to application of available options.
Animal diseases are severely affecting the production of food animals and disrupting regional and international trade in animals and animal products. Such diseases as hand, foot, and mouth disease, African swine fever, blue tongue, and classical swine fever are eminent transboundary animal diseases. These diseases are notorious for their ability to severely affect, and indeed disrupt, regional and international trade in animals and animal products. They are also notorious for the enormous financial damage and ethical violations caused when introduced into countries that are free from these diseases. The burden of these diseases involving the loss of animals and biological diversity and the lowering of production efficiency is generally much less well known or is underestimated. Declines in biodiversity have been identified as potentially increasing infectious disease transmission among ecological populations in certain cases (Keesing et al., 2010). Furthermore, these diseases threaten food security and the livelihoods of smallholders and
prevent animal husbandry sectors from developing their economic potential (Kelly et al., 2013).
Emerging and reemerging animal diseases that were considered under control are threatening trade and the disruption of animal protein distribution. The appearance of the porcine epidemic diarrhea (PED) virus, for example, in North America presents significant challenges for producers and animal health officers. The disease is a viral infection affecting swine populations with significant impact on production with potential transmission through the fecal-oral route. The introduction of this virus to North America is evidence of the need for biosecurity that is more comprehensive to include all possible ways for pathogens and harmful materials to enter the food chain. The rapid spread of PED among intensive swine premises in North America should be considered a challenge to researchers to explore better options for monitoring and surveillance systems (Box 2-1).
Porcine Epidemic Diarrhea (PED) Virus
The PED virus has affected European swine for over 40 years, but only appeared in the United States in 2013 (Kerr, 2013). PED is spread between animals through fecal to oral transmission and can result in pigs suffering from vomiting, diarrhea, dehydration, and poor appetite, among other symptoms, which can result in high death rates, especially for younger animals (Kerr, 2013). PED cannot be transmitted to humans, but has the potential to create significant economic losses due to animal sickness and death in the pork industry (USDA, 2014). In a Chinese outbreak of PED in 2010, death rates of approximately 100 percent were recorded for piglets (Sun et al., 2012). Because of the “hardy and virulent nature” of the PED virus (Canadian Food Inspection Agency, 2014), the pork industry has cause for concern regarding the effects of this illness. Although a PED vaccine exists and has been used in some countries, the vaccine may not be fully effective against all disease strains of the virus (Kerr, 2013). Research toward mitigating the effects of PED and preventing infections are of critical importance to the pork industry.
Human Health and Disease
The World Health Organization (WHO) has recognized that the worldwide upswing in resistance to antibiotics is based on a combination
of factors that includes “overuse in many parts of the world by both human and animals, particularly for minor infections, and misuse due to lack of access to appropriate treatment” (WHO, 2001). According to the U.S. Centers for Disease Control and Prevention (CDC), antibiotic use in people is a primary factor (CDC, 2013a), and the most acute problem is in hospitals. And the most resistant organisms in hospitals are emerging because of “poor antimicrobial stewardship among humans” (CDC, 2013b). Antibiotics are among the most commonly prescribed drugs used in human medicine; however, CDC estimates that up to 50 percent of all antibiotics prescribed are not needed or are not optimally effective as prescribed.
The U.S. Food and Drug Administration (FDA) recently took the major step of issuing guidance documents to promote the judicious use of antibiotics in agriculture. In particular, Guidance No. 213 established procedures for voluntarily phasing out growth promotion indications for medically important antibiotics in alignment with FDA’s Guidance No. 209 and published proposed changes to the Veterinary Feed Directive (VFD) regulation. The VFD regulation mandates the rules and responsibilities of licensed veterinarians in prescribing and administering medically important antibiotics in feed. Guidance No. 209 adopted principles that the use of medically important antimicrobial drugs in food-producing animals should be limited to uses that are considered necessary for ensuring animal health, and should include veterinary oversight or consultation. There have been reports that many leaders in industry have moved forward to implement Guidance Nos. 209 and 213 (FDA, 2014).
In addition, The President’s Council of Advisors on Science and Technology recently proposed additional findings and recommendations concerning how the U.S. government can best combat the rise of antibiotic resistance (PCAST, 2014b). This report, released simultaneously with a National Strategy on Combating Antibiotic Resistant Bacteria (PCAST, 2014a) and with an Executive Order (White House, 2014), made recommendations in three areas, including improving surveillance of the rise of antibiotic resistant bacteria and acting on surveillance data to implement appropriate infection control; increasing the longevity of current antibiotics and scaling up proven interventions to decrease the rate at which microbes develop resistance to current antibiotics; and increasing the rate at which new antibiotics, as well as other interventions, are discovered and developed.
Related to animal agriculture, the report reiterates support for FDA’s Guidance Nos. 209 and 213 described above and directed the agency to proceed with their implementation. It adds that USDA, through its Cooperative Extension Service, should establish and lead a national education program to help food animal producers comply with these guidances. The report adds that FDA should also assess progress by monitoring changes in total sales of antibiotics in animal agriculture and in use of antibiotics, where possible (PCAST, 2014b).
Related to research, the report recommends
expanding fundamental research relevant to developing new antibiotics and alternatives for treating bacterial infections, including requesting dedicated funds for the National Institutes of Health (NIH) and FDA to support fundamental research aimed at understanding and overcoming antibiotic resistance, and for Defense Advanced Research Projects Agency (DARPA) and Defense Threat Reduction Agency (DTRA) to support non-traditional approaches to overcoming antibiotic resistance. (PCAST, 2014b).
It also recommends “developing alternatives to antibiotics in agriculture, noting that USDA should develop, in collaboration with NIH and the agriculture industry, a comprehensive R&D strategy to promote the fundamental understanding of antibiotic resistance and the creation of alternatives to or improved uses of antibiotics in food animals” (PCAST, 2014b). The report states that one mechanism that should be employed is a USDA multidisciplinary innovation institute (PCAST, 2014b). Regarding coordination, the report recommends establishing an interagency Task Force on Combating Antibiotic Resistant Bacteria that should include members from all relevant agencies, as well as establishing a President’s Advisory Council on Combating Antibiotic Resistant Bacteria comprising nonfederal experts. Related to international coordination, the report notes that the federal government should support development of the WHO Global Action Plan and continue to elevate the issue of antibiotic resistance to the level of a global priority by encouraging or requiring, as appropriate, coordination among countries for surveillance, reporting, research, antibiotic stewardship, and development of new and next generation drug and diagnostics development (PCAST, 2014b).
During the last few decades, various regions of the world were infected with serious zoonotic diseases such as immunodeficiency viruses, SARS, MERS, and reemerging diseases such as tuberculosis, undulant fever and Rift Valley fever. Furthermore, there were 2.4 billion human illnesses and 2.2 million deaths per year from foodborne illness, and more than 1.7 million deaths from HIV/AIDS in 2011. Global outbreaks of influenza, for example, have occurred periodically in the human population. The viruses of the outbreaks in the 20th century were avian in origin and arose through mutational events. In particular, recent evidence of direct bird-to-human transmission has increased global concerns over the pandemic potential of these viruses (Dinh et al., 2006). Escherichia coli O157:H7 is another major public health concern in North America and other parts of the world. The feces of animals, particularly cattle, are considered the primary source of these bacteria, and major routes of human infection include consumption of food and water contaminated with feces and, to a lesser extent, contact with live animals. Human infections are often asymptomatic or result in uncomplicated diarrhea, but may progress to bloody diarrhea, kidney disease, and death (Griffin and Tauxe, 1991).
Food safety concerns pertinent to foods of animal origin often relate to Salmonella, parasite infections, antibiotic residues, Listeria, Campylobacter, Staphylococcus, and Clostridium. According to a National Animal Health Monitoring System fact sheet that detailed results of a Salmonella prevalence study, only 38 percent of sampled farms with finishing hogs had samples that were positive when tested for Salmonella (USAPHIS, 1997). Of the 38 percent of Salmonella-positive farms, the level of bacterial shedding in finishing hogs was low at an estimated 6 percent. In another study, 9.6 percent of uncooked or unprocessed samples obtained from retail stores were contaminated with Salmonella (Duffy et al., 2000). Although proper handling and cooking will prevent the consumer from becoming infected, it is of primary importance that animal science researchers work to identify means to reduce foodborne pathogens.
Antimicrobials and improvement in vaccine efficiency have saved millions of human lives. Over the course of the 20th century, deaths from
infectious diseases declined markedly and contributed to a 29-year increase in life expectancy (CDC, 1999). They also play an important role in modern agriculture and in enhancing food security by preventing disease and improving food safety for humans. Antimicrobials are also used in animal agriculture to alter the animal’s gut microflora and decrease the level of pathological bacteria present for production purposes. This aids feed conversion and hastens growth. Prudent and judicious use of antimicrobials is an important piece of the sustainability challenge. Animal agriculture, however, is at risk now of losing this progress through bacterial resistance. The CDC and WHO have identified antibiotic resistance as one of the greatest threats to human health worldwide. Resistance is now spreading to the point where there is a rise in so-called superbugs (CDC 2013a).
The use of antimicrobials in animal agriculture has come under intense scrutiny in recent years with some charging that use in animals is impacting human health. Although use of antimicrobials in animals (food animals and companion animals) is a factor that contributes to the wider pool of resistance, the problem is not limited to modern agricultural practices and stems from a number of factors, including environmental, biological, and management practices in both agriculture and human health care (Box 2-2; Salman et al., 2008). A recent OECD paper (Rushton et al., 2014) noted that the use of low-level antibiotics enhances the overall productivity of livestock systems, but could in the long term lead to antimicrobial resistance and to animal diseases that could lessen this productivity effect. The authors note the concern of health authorities about antimicrobial-resistant organisms and call for greater cooperation among national and international agricultural and health organizations in improving preventive approaches that do not depend on antibiotics used for human health. They also call for greater cooperation in gathering data and developing effective policies that balance the benefits and risks of low-level antibiotics in livestock system productivity and animal and human health.
The committee examined practices related to antibiotic use in other countries and data relating to those practices, for example, Denmark, which instituted a compulsory ban in 2000 and regularly reports on antibiotic use and resistance patterns.
Among the problems is that the number of new antimicrobials developed and approved has decreased steadily over the past three decades, from over 15 in the mid-1980s to just 2 since 2008. The drug development pipeline is failing for a variety of reasons—including the
United Kingdom Report on the Use of Antimicrobials in Animals
“Increasing scientific evidence suggests that the clinical issues with antimicrobial resistance that we face in human medicine are primarily the result of antibiotic use in people, rather than the use of antimicrobials in animals. Nevertheless, use of antimicrobials in animals (which includes fish, birds, bees, and reptiles) is an important factor contributing to the wider pool of resistance which may have long term consequences” (UK Department of Health, 2013).
scientific difficulty of discovering new drugs, challenging pathways for regulatory approval, and low return on investment. As a result, pharmaceutical companies have decreased or eliminated their investments in antibiotic drug development (PCAST, 2012). In the United States, unlike traditional animal agriculture, the farming of aquatic species has come under strict regulations concerning the use of antimicrobials. Use is highly controlled and is based on identification of the disease and whether there is an antimicrobial that will be effective against the disease. Other regulatory restrictions include treating the population for an appropriate period of time and then adhering to an appropriate withdrawal time.
Most aquaculture occurs in Asia, and use of antimicrobials is indiscriminate, most often having no foundation for choice other than convenience. In addition, any attempt at enforcement of violations is difficult. The European Union places a particular emphasis on regulating the importation of aquaculture products from Asian countries, particularly those who frequently use antimicrobial and other additive materials (EC, 2014). Application of control measures will initially require trained professionals to provide the proper diagnosis and surveillance. Standards of administration need to be developed and will require international organizations to implement a cooperative effort. Because most of the seafood consumed in the United States is imported, the question of inspection protocol for imports continues to persist. The Farm Animal Integrated Research (FAIR) effort in 2012, which was undertaken to identify key priorities and strategies for the future, noted that the “the use of antimicrobials in animal agriculture has been the source of much controversy in recent years as critics express concerns about antimicrobial resistance. Investments in research will be essential
to more clearly understand these issues and provide decision makers with science-based information to develop better-informed policies” (FASS, 2012).
As discussed above, animal science research has contributed to remarkable increases in the production efficiency of agricultural animals. It is becoming increasingly apparent that in order for research advances in animal productivity to be useful, consideration must be given to the social norms of communities and countries in which they are to be applied. Although surveys in developed countries show consistently that food quality and safety are the most important considerations for consumers (Lusk and Briggeman, 2009), there are a host of other issues that influence the acceptability, and hence the sustainability, of existing and new animal agriculture practices. These factors include environmental, economic, and social concerns (NRC, 2010), with the latter playing an increasingly important role not only with respect to the regulatory decision-making process, but in terms of shaping consumer and supply-chain purchasing decisions in many countries (Mench, 2008; Matthews and Hemsworth, 2012). Social concerns include those related to animal welfare, equity (e.g., fair labor practices, protection of vulnerable human populations and rural communities, agricultural worker health and safety), corporate social responsibility and business ethics, food security, agricultural and food traditions, and naturalness of food products (NRC, 2010; Anthony, 2012; Niles, 2013; Lister et al., 2014).
Social concerns cannot be adequately addressed using only traditional animal sciences research approaches (Box 2-3). Dealing with the complex issues associated with the values surrounding agricultural sustainability requires transdisciplinary approaches that bring together experts in the natural sciences, social sciences, and humanities to address wicked problems (Peterson, 2013). A critical element of addressing social challenges is to determine what the public knows (“objective knowledge”) and believes they know (“subjective knowledge”) about animal agriculture technologies and practices (Costa-Font et al., 2008). Increasing public understanding of animal agriculture and aquaculture technologies is important. Public perceptions of risks and benefits of particular technologies are dynamic and factual information can shape those perceptions as long as it is conveyed by sources that are trusted
(Costa-Font et al., 2008) and in language that resonates with the various stakeholders. Perceptions are also shaped by cultural values and can be influenced by information that creates uncertainty about the safety or importance of the innovation in question, even if that information comes from individuals or organizations with vested interests (Oreskes and Conway, 2010). Research on climate change provides some insights on which animal agricultural technology might build. It indicates that information about technology is most likely to be accepted if it is perceived as being relevant to the recipient, based on adequate scientific information, produced in a way that is unbiased and respectful of stakeholders’ divergent values and beliefs, and fair in its treatment of opposing views and interests (Cash et al., 2003).
Genetically Engineered Salmon
The potential fate of genetically engineered salmon in the marketplace represents one example of the effects social concerns can have on the adoption of new technologies in animal agriculture (Van Eenennaam and Muir, 2011). In 1995, a U.S. company called AquaBounty applied for FDA approval to market Atlantic salmon transgenic for expression of a Chinook salmon growth hormone gene. The insertion of this gene leads to a doubling of fish growth rate and the potential for increasing the affordability and availability of salmon. During the two decades in which the application was under consideration, public debate grew increasingly heated, with more than 1.5 million people writing letters in opposition to FDA approval of what became dubbed the “Frankenfish.” Concerns were raised about the welfare of the transgenic salmon themselves, their potential to escape and cause the collapse of wild salmon populations, food safety issues, negative impacts on commercial salmon fishermen, and, quoting Alaska Senator Lisa Murkowski, “messing with Mother Nature” (Welch, 2014). In 2014, the Senate Appropriations Committee passed an amendment requiring labeling of transgenic salmon if they are approved by FDA for human consumption, although it appears that approval may be moot—a coalition of 30 consumer, food safety, environmental, sustainable agriculture, public health, and animal health and welfare organizations have successfully lobbied 65 major supermarkets to pledge that they will not sell it. The approval of the application is still pending.
The number of hungry and malnourished people, due to the recent sharp increase in food prices both nationally and internationally, has increased the awareness of policy makers and of the general public to the fragility of the global food system. Poverty is associated with endemic and chronic diseases, poor nutrition, environmental challenges, and a lack of leadership in understanding public health and food safety. Poverty affects one out of seven people in the world today. Approximately 2.6 billion people worldwide receive less than $2 a day and 1 billion people live on $1.25 a day and suffer from chronic hunger. Globally, 25 percent of children are born malnourished with compromised growth, have weakened cognitive and immune systems, and risk early childhood death (FAO, 2009a; Lam et al. 2013).
The greatest concentration of poverty is in sub-Saharan Africa and in South Asia, where subsistence farming is associated with mixed farming of both food animals and crops. In addition, many people are nomadic, following their animals as they seek water and forage on open ranges in desert regions. It is estimated that there will be a major wave of farmers leaving rural areas and migrating to urban areas over the next three decades, spurred by global and regional climate change impacts. Such a transformation is challenging for the world as there are significant concerns about whether there will be adequate and safe food, nutrition, and water resources by midcentury (FAO, 2009a). Food animals are crucial to the lives of poor farmers and their children. In developing countries, animal agriculture contributes to employment and GDP, but poverty and malnutrition persist. The production of food animals as an animal protein source increasingly expands beyond household and community food animal assets into commercial production. Animal health issues confront the nearly 1 billion poor producers with consequences for their livelihoods and human health (Kelly et al., 2014).
Concerns about animal welfare increasingly shape the acceptability and adoption of food animal production technologies. Although concerns about animal welfare are not new, it was not until the 1960s that significant public concern about animal welfare associated with the intensification of animal agriculture began to be apparent. These concerns centered mainly on confinement rearing and led to an
influential British government committee report that stated that both the physical and mental states of animals were important for welfare and recommended that all farm animals should be provided at least sufficient space to “stand up, lie down, turn around, groom themselves and stretch their limbs,” referred to as the “Five Freedoms” (Brambell, 1965). Over time, this list of freedoms was expanded to include freedom from fear, distress, discomfort, pain, injury, disease, hunger, and thirst as well as freedom to express normal behaviors via provision of appropriate facilities and social companions. These Five Freedoms have been accepted by legislative and standards-setting bodies in many countries as ethical principles that underlie the care and treatment of farm animals. They also form the basis for a joint statement by the American Veterinary Medical Association (AVMA) and the Federation of Veterinarians of Europe (FVE) describing the roles of veterinarians with respect to animal welfare (AVMA, 2014).
As public interest in and concern about animal welfare increases globally, emphasis on regulation, voluntary standards setting, and the development of animal welfare labeling programs continues to increase. Many countries now have regulations, codes of practice, or standards covering animal transport and humane slaughter, and an increasing number also have standards covering the breeding, housing and management of farm animals (FAO, 2014a). The most far-reaching regulations are in the European Union, which has banned several common animal housing systems because they involve a high degree of confinement; many countries within the European Union have also banned or are planning to ban painful procedures such as castration or beak trimming, or at least require that pain relief be provided when these procedures are performed. Although the main focus has been on food animals and poultry, there has recently been growing interest in the welfare of farmed fish, with particular emphasis on reducing pain and stress during handling and slaughter (Branson, 2008).
National and multinational retailers have also played a significant role with respect to animal welfare in developed countries via their purchasing preferences and specifications (Veissier et al., 2008). A major thrust in the last few years has been the development of animal welfare standards that can be audited to provide assurance that they are being followed. In the United States there is now a mix of these standards that have been developed by different sectors including industry, retailers, and independent animal welfare certification programs (Mench, 2008). Animal welfare research has provided an important underpinning for
these kinds of standards. However, much scientific information is still lacking (Rushen et al., 2011), and this information needs to be generated in order to ensure that standards are scientifically based while still addressing evolving social concerns about the treatment of animals. It is clear that animal welfare concerns can rapidly drive major changes in agricultural animal production methods, as is currently happening for egg production in the European Union and United States (Box 2-4). The challenge going forward will be to ensure that new or modified housing systems and management practices developed to improve animal welfare also contribute to maintaining or enhancing other aspects of the sustainability of animal agriculture (Tucker et al., 2014).
Egg Production in Transition
Egg production provides a case study of the way in which social issues can affect animal production systems and, consequently, the research needed to ensure that new systems are sustainable. Eggs are a primary and inexpensive source of animal protein in both developing and developed countries, with global production of nearly 65 tonnes annually from approximately 5 billion hens. Most egg-laying hens are housed in conventional cages. This housing system began to be adopted on a large scale in the 1950s because it reduced the potential for transmission of soilborne parasites, facilitated egg collection, improved egg cleanliness, and was economically efficient; however, public pressure is now propelling the egg industry in developed countries to move away from conventional cages because of concerns about crowding and behavioral restriction of the hens (Mench et al., 2011). This pressure and the resulting mechanisms for change have come from different sources in different regions and countries, illustrating the complex social matrix surrounding animal agriculture. One approach has been legislative, with the European Union and New Zealand banning conventional cages in 2012. Australia has not regulated egg production methods, but a large proportion of consumers there now preferentially purchase free-range eggs, which is moving the egg industry toward alternative production systems to retain market share (Mench et al., 2011). In contrast, in the United States the main egg producer group, the United Egg Producers, has announced their members’ intentions to discontinue the use of conventional cages despite the fact that more than 90 percent of consumers purchase conventional cage eggs. This has been driven by anticipation of
consumer dissatisfaction with the current production system, resulting in state-by-state regulation, as has already occurred in six states. Retailers have also played a role in other countries. In Germany, for example, the major retailers decided to purchase only cage-free eggs, despite the fact that German producers were already transitioning to so-called enriched cages containing perches, nests and a scratch area, which were allowed under both European Union and German law. Animal welfare concerns are thus driving a global shift in egg production systems that will need to be accompanied by a new research effort focused on identifying optimal housing, genetics, and management for these systems, as well as improving other aspects of their sustainability such as those related to environmental impacts and food affordability (Mench et al., 2011).
Animal welfare is now becoming an increasingly prominent international issue, and as such, will potentially affect not only the United States, but animal production practices globally. The OIE began the process of developing global standards and also proposed a definition of animal welfare, which has been accepted by the 178 OIE member countries and territories:
Animal welfare is how an animal copes with the conditions in which it lives. An animal is in a good state of welfare if (as indicated by scientific evidence) it is healthy, comfortable, well nourished, safe, able to express innate behaviour, and if it is not suffering from unpleasant states such as pain, fear, and distress. Good animal welfare requires disease prevention and appropriate veterinary treatment, shelter, management and nutrition, humane handling and humane euthanasia or humane slaughter…. (OIE, 2014).
This definition echoes many of the points in the Five Freedoms. This definition, and the associated 10 General Principles for animal welfare adopted by the OIE (Box 2-5; Fraser et al., 2013) will be very important for global trade in animal products because the OIE is the WTO reference organization for standards setting for animal health. The OIE already has global animal welfare standards for transport and slaughter as well as the production of beef and chicken, which are the two most internationally traded commodities.
World Animal Health Organization General Principles
- Genetic selection should always take into account the health and welfare of animals.
- The physical environment, including the substrate (walking surface, resting surface, etc.) should be suited to the species and breed so as to minimize risk of injury and transmission of diseases or parasites to animals.
- The physical environment should allow comfortable resting, safe and comfortable movement, including normal postural changes, and the opportunity to perform types of natural behaviour that animals are motivated to perform.
- Social groupings of animal should be managed to allow positive social behaviour and minimise injury, distress and chronic fear.
- Air quality, temperature and humidity in confined spaces should support good animal health and not be aversive to animals. Where extreme conditions occur, animals should not be prevented from using their natural methods of thermoregulation.
- Animals should have access to sufficient feed and water, suited to the animals’ age and needs, to maintain normal health and productivity and to prevent prolonged hunger, thirst, malnutrition or dehydration.
- Diseases and parasites should be prevented and controlled as much as possible through good management practices. Animals with serious health problems should be isolated and treated promptly or killed humanely if treatment is not feasible or recovery is unlikely.
- Where painful procedures cannot be avoided, the resulting pain should be managed to the extent that available methods allow.
- The handling of animals should foster a positive relationship between humans and animals and should not cause injury, panic, lasting fear or avoidable stress.
- Owners and handlers should have sufficient skill and knowledge to ensure that animals are treated in accordance with these principles.
Political factors and policy development have considerable influence on animal agriculture decision making and therefore necessarily affect the future research agenda. Requirements for animal production and trade in animal protein products vary widely from country to country. Additionally, policies that affect animal agriculture in the United States and other countries are dynamic and change over time. Likewise, research needs are not static and must consider the shifting political realities and controlling policy decisions.
Examples of policies that affect animal agricultural research needs are easy to find. The United States has an aggressive ethanol production mandate that has resulted in dramatic price increases in corn, with cascading impacts on land uses, especially in the Midwest (Donner and Kucharik, 2008; Wright and Wimberly, 2013). The increase in ethanol production in the United States compels the need for additional research in alternative feeds for animal production, a topic that would not be a top priority except that it arises from ethanol policy. Another example is the use of beta-agonists to promote growth and increase lean muscle in cattle, which are approved for use by the USDA in the United States (Texas A&M AgriLife Extension, 2013) and have been widely found in Brazilian beef even after a temporary ban (Beef Central, 2013). Internationally, however, China, Russia, Taiwan, and other countries have banned the use of beta-agonists (Centner et al., 2014). Differing international requirements create trade and production challenges to animal agriculture industries.
Protein trade is also subject to disparate phytosanitary inspection practices at international borders which may not be related to food safety but instead are designed to address unrelated political concerns. The trade implications of animal welfare standards are becoming obvious in Thailand, Argentina, and other rapidly developing countries, which are increasing their export markets for animal products by producing according to EU- or European country–specific standards (Bowles et al., 2005). In addition, some multinational companies are beginning to harmonize and enforce their animal welfare standards or preferences globally. For example, Unilever recently announced that after having significantly increased its purchase of cage-free eggs in Europe and the United States, it will purchase only cage-free eggs globally by 2020 (WorldPoultry, 2013). These types of changes could have significant effects on global development of animal agriculture as well as the level
of food availability by influencing which producers can supply to those companies, potentially favoring larger, better-capitalized producers able not only to produce sufficient products but to commit resources toward ensuring compliance.
Although partly attributable to social habits and practices, food waste and food loss are other areas that are driven by policy choices. Food safety requirements and government-imposed shelf-life requirements related to mandatory expiration dates cause considerable loss of food regardless of actual health threats. The loss of this food volume has been estimated to be approximately one-third of food produced for human consumption (Gustavsson et al., 2011). Government-imposed political and policy choices certainly present an ongoing challenge concerning the future considerations and corresponding direction of animal research efforts going forward.
Even if a food animal system in some region of the world is considered to be sustainable in an environmental or social sense, it cannot thrive or survive unless that system is also economically sustainable. Animal industries face economic constraints from numerous sources, including domestic and international regulations and trade barriers, market structure, knowledge, access to resources, financing, access to veterinary care, cost of inputs, and technology (Box 2-6). These constraints are not uniform throughout the world and can vary even within regions. For example, producers in developed countries, utilizing more intensive systems may be constrained by government intervention in the markets, whereas smallholders in developing countries may be more constrained by risk and uncertainties in weather and market vagaries in the regions where they operate (Jarvis, 1986).
The sustainability of food animal production is particularly affected by existing economic policies (Schillhorn, 1999; Upton, 2004; Otte et al., 2012). Policies that enhance the efficient functioning of markets allow food animal producers to receive appropriate signals regarding resource allocation and costs (Upton, 2004). Food animal markets are sensitive to both economic and technical forces (Steinfeld et al., 2006b). Consequently, food animal development strategies and policies must be informed by a clear understanding of not only the various production constraints faced by producers in and across regions and countries but also the demand for different food animal products (Otte et al., 2012).
Although government intervention in markets is often distortive, some intervention is justified on various social grounds, such as protection of populations from animal diseases and communities from land grabbing, the restriction of imports to protect producers from international dumping, or the need to initiate long-term industry development (Upton, 2004). In general, food animal development in most countries can improve domestic welfare, help alleviate poverty, and reduce food security concerns if food animal markets operate free of distortive intervention and investments are made in complementary research, infrastructure, and animal health programs to support the sustainable growth of the industry (Jarvis, 1974, 1986; Schillhorn, 1999; Otte et al., 2012). Historically, research, education, and nondistorted market signals have proven fruitful in the development of sustainable food animal production.
Economic Forces in Animal Agriculture
The role of economic forces in constraining the ability of livestock industries to meet growing food demand and contribute to global food security can be illustrated by adapting the Mosher framework as elaborated by Timmer et al. (1983) to livestock. This framework considers the relationship between the actual performance of an agricultural system and its potential performance given technical and economic constraints to growth (i.e., a yield gap). Understanding the drivers of the yield gap can help guide technology and capacity development. The performance measure is yield (output per animal), which may vary widely across livestock on farms in a given region and across regions. Given some level of technology (which includes the breed), yield variability results from regional differences in environmental, social, climatic, political, and other conditions. Even within a region, however, yields will vary because some producers may have better access to pastures or water, commercial markets, or agricultural extension services, or may utilize more efficient management techniques. Whatever the reasons, the observed yield variations across livestock of a particular type are ranked from highest to lowest in the Mosher framework along the vertical axis of a graph (Figure 2-1). The horizontal axis is the percentage distribution of livestock of that type by yield level.
For beef cattle, curve a in Figure 2-1 represents the distribution of beef yields achieved by livestock raised in some region, referred to as the “achievement curve.” The yields along the curve are ordered from highest to lowest so that, fiven the differences in yield performance of beef cattle raised, the achievement curve slopes downward from left to right. Curve t represents the technical ceiling to yield performance. The technical ceiling represents the maximum biologically possible yields that can be achieved given available techology. Curve e represents the economic ceiling to yield performance, which is the yield distribution possible when farmers maximize their profits and economic conditions are at their optimum given the social, political, cultural, environmental, infrastructure, and othe exogenous conditions impaction the cattle production system. The position of curve e in the graph depends of how well economic systems function and the constraints imposed by the exogenous conditions. Obviously curve e cannot lie above curve t. How for below curve t it will lie is determined by the efficiency of the economic system in delivering inputs such as production financing, genetic material, and feedstuffs to producers and in determining prices, material, and feedstuffs to producers and in determining prices, transporting, feeding, and processing live animals, and delivering meat products to end users, Lack of infrastructure, unfavorable policies relating to production, confined animal feeding, the cattle—environment interface, food safety regulations, and international trade as well as restrictive land tenure arrangements and many othe conditions increase the technical and economic yield gap. At the same time, droughts and other unfavorable weather conditions, lack of technical training and education, poor access to extension services, and other factors affect the ability of farmers to maximize profits and can exacerbate the technical and can exacerbate the technical and economic yield gap.
Investments in new technology,
such as improved genetics, improved feeding regimes to enhance yield gains, or improved livestock or pasture management techniques, can raise the technical ceiling from t to somewhere like t′ creating the opportunity for increased profitability which may raise the economic ceiling (e curve), leading to the possibility of an increase in yield performance. However, unless investments are also made to relieve any constraints to an increase in the economic ceiling, actual yield performance will not increase. Improved technology may not raise productivity and profitability of cattle production in a region such as Africa if producers have poor access to commercial markets, production financing, education, and/or extension services and face inefficient delivery systems hampered by lack of refrigeration, poor quality roads, bridges, ports, and other critical infrastructure. Agricultural policies that discriminate against cattle production in favor of crops or environmental improvement can also hinder productivity. Thus, a consideration of the economic constraints to increased meat production must accompany investments in new technologies if the potential returns to those investments are to be realized.
SOURCE: Used with permission from the World Bank. Timmer et al., 1983. Food Policy Analysis.
Animal production systems are complex, and decisions about the direction of future research needed to improve their sustainability are influenced by an array of factors identified in this chapter. It seems unlikely that there is a “one-size-fits-all” solution to achieve sustainability that cuts across domains such as production systems, species, and regions with different climates, cultures, and socioeconomic conditions. In fact, these kinds of solutions are difficult to achieve even within particular domains, because sustainability is a “wicked problem.” Wicked problems require a much different research approach than tame problems (e.g., determining the energy requirements of a growing steer) that research from the traditional animal science disciplines have served so well. Peterson (2013) characterizes the wicked problem of sustainability in animal agriculture as having four properties: (1) no definitive formulation of the problem exists; (2) its solution is not true or false, but rather better or worse; (3) stakeholders have radically different frames of reference concerning the problem; and (4) the underlying
cause-and-effect relationships related to the problem are complex, systemic, and either unknown or highly uncertain. Systems approaches have been advocated as a means to address wicked problems (Williams and van’t Hof, 2014).
Much of the sustainability predicament stems from differences in values and interests from the different stakeholders involved (Norton, 2012). As such, stakeholders often have divergent answers to the questions, “What is the current state of animal agriculture sustainability?” and “What should it be?” By failing to recognize different ways to formulate the problem and by advancing straight to solutions, intractable debates emerge (i.e., problem of legitimacy; Cash et al., 2003). Decisions about “what is sustainability” drive research questions, tools, and metrics. Additionally, stakeholders in animal agriculture come from different sections of the production chain (e.g., consumers vs. primary production vs. processors or retailers) and often use different vocabularies. Different vocabularies are also used in different animal sciences disciplines and related fields of study (e.g., agricultural economics), which can create miscommunications among those within and outside of academia.
The sustainability of animal agriculture is further complicated because it involves addressing other inherently challenging problems, such as climate change, animal welfare, and food security. There is a temptation to try to resolve these kinds of complex problems by developing quantitative models. However, unintended or unforeseen consequences and externalities associated with a change in animal production will always exist and accordingly fall outside the capabilities of any model or research framework employed. Furthermore, integrating sustainability metrics is also influenced by values, which inevitably leads to a decision about what metrics are more important and how much more important (e.g., is animal welfare more or less important than environmental impact in deciding which production system to use?). Many animal scientists are not trained to consider the role of their own and others’ values in making decisions about sustainability issues related to the animal sciences. Ignoring differences in values, including differences in risk tolerance, creates significant challenges in making the problems associated with sustainability easier to solve. Incorporating quantitative approaches, such as participatory strategies (Swanson et al., 2011) into the research enterprise can help to address sustainability issues by involving a broad array of stakeholders in decision making (de Boer and Cornelissen, 2002; Mollenhorst and de Boer, 2004; NRC,
2011). Animal science research can contribute to assessments of sustainability by providing data that reduce the uncertainty about underlying causes and effects and define degrees of risk (Goldstein, 1999). Arriving at the “best” technical solution, however, involves increasing stakeholder participation and acknowledging the role of values in decision making and not just “educating the public” (Slovic, 1999). The involvement of social scientists in addressing these complex issues will lead to animal science research and technology transfer that is more relevant and consequential.
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