Sustainability in the Poultry Industry

Q: How can nutritionists determine the environmental impact of diet formulation and animal production?

Data enable nutritionists to determine the environmental impact of diet formulation and animal production (Kleyn et al., 2021a). However, to do this effectively, it is essential to know the source and origin of each ingredient parcel.

I.INTRODUCTION

A high degree of volatility with regard to the pricing and supply of inputs has arisen. This situation began with the COVID-19 pandemic and the negative effect it had on the global supply chain, and has been exacerbated by the Russian-Ukrainian war. This state of affairs will likely persist until at least the end of 2023 (Mulder, 2022). It has given rise to the intermittent non-availability of several essential feed ingredients. Coupled with these short- to medium-term stresses are several mega-trends and pressures. The global demand for eggs is expected to increase by 65% (Preisinger, 2018) and for poultry meat by 121% (Alexandratos & Bruinsma, 2012) by 2050. Poultry forms a critical component of food security, especially in communities that are deprived of nutrient-rich foods (UN, 2015). As citizens become more urbanised, providing protein at a price the urban poor can afford becomes an essential component of food security (Skinner & Haysom, 2016).

The overarching consideration for agriculture should be sustainability. The definition of sustainability is straightforward: Sustainable systems should meet the needs of the current generation without compromising the ability of future generations to meet their own needs. In practice, sustainability is a concept with four facets, namely environmental, ethical, economic and enactment or enforcement (the four Es of sustainability). Any scrutiny of sustainability should consider all aspects, not only the aspect that suits a particular narrative. Consumer demands are evolving, with more people wanting to eat ‘natural’ products, a trend supported by celebrity chefs and the retail and quick-service restaurant sectors. These trends have compelled the poultry industry to change production methods, forego many effective technologies, and implement exacting food safety measures along supply chains.

Regrettably, simple solutions to complex problems seldom exist. From a cynical perspective, many believe that anything ‘alternative’ is likely to address the issue of sustainability in animal production. This includes alternatives to meat, alternative production systems, alternatives to antibiotics, the use of alternative feed ingredients, and the development of alternatives to traditional retail chains as a route to market. A more realistic and pragmatic approach is required, which includes addressing many existing conundrums and the alternative mindset required of consumers, some of which this paper covers.

II. SHORT-TERM CONUNDRUMS

a. Sustainable Poultry Production

Sustainability is important in both the short and the long term. Many food production systems are unsustainable and will continue to degrade the environment and compromise our ability to produce food. Mainstream agricultural development still concentrates on productivity and places limited focus on sustainability (Rockström et al., 2017). Under a ‘business-as-usual’ scenario, the harmful effects of agriculture on the environment will continue to increase. This will result in converting forests and savannahs into cropland, generating air and water pollution, increasing greenhouse gas (GHG), and threatening biodiversity (NAS, 2021). Attempts to improve welfare through alternative production systems, including organic and free-range, may harm the environment and sustainability (De Jong & Butterworth., 2016). Advances in environmental and ethical aspects will be restricted by divergent views on the economic characteristics of future agricultural systems (Wojtynia et al., 2021).

The poultry industry is probably more sustainable than other animal sectors (Pelletier et al., 2014; Fry et al., 2018), which places the industry in a strong position to buy scarce resources and convert these into edible protein. GHG from agricultural activities has contributed to climate change (Godfray et al., 2018; NAS, 2021). It is estimated that animal agriculture uses about 70–74% of all agricultural land and contributes about 15% of all GHG, but poultry is only responsible for about one-third of this amount (Steinfeld et al., 2006; Godfray et al., 2018). Changes to one aspect of sustainability often impact negatively on other areas of sustainability (EU, 2001). Food security will most likely be ensured by ‘sustainable intensification’ (Rockström et al., 2017), which entails producing more food on existing acreage. This is at odds with the current move to less intensive systems.

b. Ingredients

The demand for resources is relevant because most feed offered to poultry originates from commercial cropping, making ingredients a vital component of sustainability. Agriculture’s extensive use of land, water and other resources is harmful to the environment and negatively affects biodiversity. Perhaps the largest impact of the current global turmoil is an erratic supply of feed ingredients, leading to price volatility. The use of alternative, preferably locally sourced, ingredients is often espoused as a means of enhancing the sustainability of animal production. The local supply of ingredients is characterised by so-called yield gaps. For example, the maize yield in the USA is 10 tons/Ha while, in Africa, it is one ton/Ha. This presents a short-term problem but offers huge scope for improvement in the longer term. The use of genetically modified (GM) technology brings new prospects in addressing food security problems (Muzhinji and Ntuli, 2020). GM crops facilitate no-tillage and conservation tillage practices that help to control soil erosion, conserve soil moisture, support carbon sequestration, decrease GHG emissions, reduce pesticide spraying, and increase crop yields by 16% (Van Acker et al., 2017). Despite the scientific consensus that GM crops are safe to eat, they are viewed with scepticism by many institutions and governments (Van Acker et al., 2017; Muzhinji & Ntuli 2020).

It is often expounded that the use of alternative ingredients in poultry diets is a sustainable option, but this presents a number of conundrums. First, there are only twelve or so major feed ingredients. Most commercial nutritionists spend a significant amount of their lives on the lookout for viable alternatives – and fail. Second, often the nutrient content is unknown, the quality is variable, and the quantities are constrained. In addition, many alternative ingredients are over-priced or of low nutrient density. It is essential that commercial nutritionists evaluate the cost-effectiveness of alternative ingredients, not just in terms of formulated diets, but also bearing in mind return in the poultry production enterprise.

Ingredients vary in terms of their environmental impact. Production methods and land-use change (LUC), which describes practices such as deforestation or the re-deployment of ‘set aside’ land, impact on the carbon footprint associated with an ingredient (Cappelaere et al., 2021). Both the Global Feed LCA Institute (GFLI) (2022) database and the INRAE-CIRAD-AFZ (2022) feed tables carry data suitable for use in least-cost formulation systems. These data enable nutritionists to determine the environmental impact of diet formulation and animal production (Kleyn et al., 2021a). However, to do this effectively, it is essential to know the source and origin of each ingredient parcel.

c. Protein Usage

Modern broiler genotypes respond to protein (Naranjo and Lemme, 2017; Aviagen, 2022). Coupled with rising demand, this will result in a huge increase in protein requirements. Problematically, the protein levels in our major ingredients are declining, while yields of proteinaceous crops are lower. Most protein is derived from vegetable sources, with soya beans being the most important. Smaller amounts of rape, sunflower and other lupins are also used. The current turmoil in Ukraine has reduced the supply of sunflower meal, but it has not had any real impact on the global soybean supply, although the price of these beans remains volatile (high). It is unlikely that we will suffer a substantial shortage of soya beans in the short term.

Broiler diets high in essential amino acids (AA) are more expensive, but they lead to improved performance (Naranjo & Lemme 2017). Modern layers are lighter and lay smaller eggs than historic breeds. While they produce more eggs in their lifetime, they still lay a single egg daily. The utilisation of protein and energy has not changed over the past three decades (Kleyn et al., 2021b); thus, it is likely that the nutrient requirements of laying hens have declined. Pottgüter (2013) contends that modern genotypes perform adequately in any production system, provided that adequate feed intake is achieved. This may not always be the case in commercial production systems, which needs to be reflected in feed specifications.

The justification for reducing dietary crude protein (CP) is compelling (Greenhalgh et al., 2020a). Reduced CP levels can be fed applying enhanced ideal AA profiles and by utilising an ever-widening range of synthetic AA. Lower CP diets lead to an increase in performance, improved protein digestibility, a reduction in water intake, reduced manure nitrogen, and better bird welfare (Belloir et al., 2017; Chrystal et al., 2020). Lowering dietary CP by 1% reduces the carbon footprint of broiler production by 102 kg/ton of broilers produced (Martin, 2020). When reducing dietary CP levels, protein sources such as soya beans and fat are replaced by feed-grade AA and cereals (Chrystal et al., 2020; Cappelaere et al., 2021), giving rise to an increase in dietary starch and decreases in dietary lipid and true protein.

Three conundrums arise when considering protein usage. First, modern genotypes perform better when offered higher levels of essential AA. Second, minimum fat levels must be maintained in poultry diets. Significantly, however, it is e not appreciated that there is most likely a ceiling for the starch content of a diet (Greenhalgh et al., 2020b). Third, despite the overwhelming evidence that low CP diets support normal production levels, many countries have set minimum CP levels in their regulations, which has a negative impact on sustainability.

d. Dietary Energy

Energy is the most expensive component of the diet in both broilers and laying hens. Most energy is provided in the form of soluble carbohydrates (starch) and fat. While surplus protein can also be used as an energy source, it is utilised less efficiently in birds than in mammals (Cappelaere et al., 2021). Deciding on optimal energy levels is central to commercial poultry nutrition. These levels should be determined by using the relative cost and availability of ingredients, together with the value of poultry meat or eggs produced. Broadly speaking, when fat is relatively cheap, high-energy diets tend to yield higher returns, while readily available, less expensive ingredients (cereal by-products, for example) make low-energy diets more attractive. Currently, all feed ingredients are expensive. The price of grain has increased by 60–70%, while feed oil prices have more than doubled. When cereal by-product supplies are adequate, they offer a cheaper alternative to commercial nutritionists. However, the moment supplies become constrained, prices shoot up and may even surpass those of grain.

It is at this point that one of the real conundrums of commercial nutrition begins. Clearly, if the price of fat trebles, all calculations regarding optimal dietary energy levels need revising. Logic dictates that dietary energy levels (nutrient density) should be reduced. However, our current practices might predicate any of the decisions made. For example, many millers add oil into the mixer to improve pellet throughput and then add more fat as a post-pelleting application to improve pellet quality. Unless millers are prepared to change this paradigm, they will be trapped using fat at $3.00/kg. Conversely, if the supply of milling by-products is constrained, the opportunities to reduce dietary energy levels may be limited. Remember, shipping low-density ingredients over distances negatively impacts sustainability. A final complication is commercial reality. On the whole, feed millers do not have the freedom to make changes to feed specifications or the selling prices of their products. Poultry producers in the main expect a certain feed efficiency (FCR) which cannot be guaranteed with reduced dietary energy. Alternatively, the likelihood exists of outpricing themselves if energy levels are increased.

e. Phosphorus

It takes about one ton of phosphate (P) to produce 130 tons of grain (Vaccari, 2009). In the long term, it is estimated that the supply of phosphate will fall below requirements by 2040 (Nedelciua et al., 2020). A large portion of phosphate originates from Russia, and the current turmoil has disrupted its supply. Morocco, the largest supplier of phosphate, has filled the void – but at a substantially higher price. The first issue is what to do if phosphate supplies are constrained. The rapid mineralisation of the skeleton of young chickens means that starter diets should take priority when supplies are limited. Second, the values published by the primary breeders (Aviagen, 2022; Cobb, 2022) for the grower and finisher phases exceed those published in the scientific literature (Angel, 2022) by some margin. In all likelihood, P levels can be reduced in the later stages of the broiler production cycle. The published requirements for laying hens (Lohman, 2020; Hy-Line, 2022) are also generous. Scientific studies to determine P requirements for laying hens show that far lower levels are adequate (Lambert et al., 2014).

III. LONG-TERM CONUNDRUMS

a. Consumers

Public opinion in developed countries is that ‘organic’ is natural, healthy and sustainable while intensive farming and antibiotic use are bad. This perception has led many consumers to assume, incorrectly, that alternative production systems are more sustainable. Unfortunately, a number of perceptions tarnish our industry: such as production occurring on factory farms; that animal welfare is flawed; poultry products contain hormones (erroneously so) and residual antibiotcs that may be harmful. Many of these beliefs are based on perception and misinformation, often created by the poultry industry itself which has used ‘Hormone-free’, ‘Drug-free’ and ‘Free-range’ as marketing slogans for decades. Consumer concerns, fueled by food scares and the desire to eat healthier and safer food, influence food purchasing patterns (Magkos et al., 2006; Bray and Ankeny, 2018). Consumers want cheap, safe and sustainable products – at low prices. There is a lack of appreciation for what alternative production systems mean in terms of sustainability, or for how high product costs may negatively affect food security.

b. Antibiotic Use

The danger of people imbibing drug residues from consuming poultry products, and the notion that these drugs contribute to an increase in drug-resistant bacteria, are more perceptions than realities (Bywater & Casewell ., 2000; Cervantes, 2015). Evidence suggests that issues of anti-microbial resistance in human medicine are primarily due to the incorrect use of antibiotics by people rather than adverse effects derived from food animals (UK Government Office for Science, 2011). Regardless, antibiotics have been banned or voluntarily removed in many countries. Public perception is that antibiotic use must be handled effectively. Thus, the poultry industry needs to operate as responsible stewards of the limited compounds that we have at our disposal.

A conundrum with regard to antibiotic use arises in the developing world where the majority of smallholder farmers reside in the tropics. Not only are these farmers deprived, but also they inhabit areas where people and livestock live at high densities, frequently in close proximity. Biosecurity is often poor, and environmental conditions favour pathogen growth and year-round survival. These poverty-stricken people will be most impacted by a blanket withdrawal of antibiotics from animal agriculture (Robinson et al., 2017). Zoonosis is a real danger, and animal death represents a concurrent bank foreclosure and an empty pantry.

c. Alternative Production Systems

Poultry production systems that offer outdoor access to chickens (alternative systems) are potentially better for chicken welfare. However, these systems are associated with public health and food safety risks (Van Asselt, 2019). They have a direct bearing on resource usage and therefore on environmental sustainability (Williams et al., 2009). Alternative systems have a lower environmental burden when measured per unit of land use, but more land is required in total, increasing the burdens per bird or egg produced. Alternative systems are more ethically acceptable to consumers but, if welfare is measured in terms of flock mortality, then conventional systems are the more principled choice (Weeks et al., 2016). Production costs for alternative systems are higher, for instance; in fact, the cost of conventional systems is about one-third of the cost of organic production (Van Horne, 2020).

The latest global trend is the production of ‘slow-growing’ chickens. Widowski (2020) found that many indicators of welfare are directly related to growth rate, making slow-growing chickens an option on welfare grounds. Petersen (2017) estimated that if one-third of the US broiler industry switched to slow-growing systems, nearly 1.5 billion more broilers would be required annually. This would necessitate using an additional three million hectares of land for feed production and result in 12 million tons of additional manure. Conversion to cage-free egg production systems leads to an increased production cost of 14–28% due to higher feed intakes, increased mortality, more downgraded eggs, and greater space requirements (Preisinger, 2018).

An aspect that is often overlooked is the importance of subsistence (small-scale) poultry farming, which currently contributes 8% of egg production and 2% of global poultry meat production (Mottet and Tempio, 2017). It must be noted that 2.5 billion people rely on small farms for food (FAO, 2013). Poverty alleviation and sustainability targets will only be met by fostering small-scale, local production using local ingredients. This will require massive inputs from governments, NGOs and commercial companies. It would be unjust to expect these producers to tackle this role as ‘organic’ farmers, as suggested by some authorities (UNEPUNTAG, 2008). Small-scale farmers face structural and market-related challenges. It is unlikely that they will receive the premium prices required to overcome the higher input costs associated with organic production.

d. Precision Nutrition

Achieving ‘precision nutrition’ is a lofty goal that nutritionists continually strive for. Although we still use CP as our standard descriptor, it has been known since the 1930s that it is impossible to describe the actual protein content of ingredients by a single variable (Jones, 1931). Most, if not all, energy systems are based on the determination of apparent metabolisable energy (AME), yet it is still unclear how best to determine values for ingredients (Mateos et al., 2019). While energy continues to be construed as a property of the diet rather than a property of the bird consuming the diet, ‘precision nutrition’ is likely to remain elusive.

IV. DISCUSSION

In the medium term, high prices and ingredient shortages will probably be overcome, but long-term issues will only be solved using a holistic view. Many concerns of poultry producers and consumers are interwoven. A realistic approach will be required by all parties if the increased demands for animal products are to be met in a sustainable manner. In a perfect world, sustainability would be enhanced by the practice of precision nutrition. While improvements in our methods and procedures inch us towards this goal, there are still major gaps in its knowledge. Table 1 summarises some of the conundrums faced by the poultry industry. There are often more questions than answers.

Table 1 - A summary of some of the conundrums facing poultry producers and nutritionists.

Focusing on a single aspect, such as bird welfare, may not be sufficient to ensure sustainable poultry production. If there is an honest desire to become more sustainable, all role players in the poultry supply chain, and our consumers, need to be involved. Feed ingredients will need to be produced efficiently, as close to production sites as possible. Producers must continue to improve feed efficiencies and lifetime performance. More poultry products will need to be produced locally by small-scale farmers. Since organic or alternative production systems use more land (which may not exist) and have larger carbon footprints than conventional systems, consumers will have to make informed decisions about which products they purchase. The paradigm needs to shift from ‘natural’ to ‘sustainable’ products. As an industry, poultry producers need to market sustainable product ranges. The industry must ensure that consumers understand why this is being done, in order or them to make the correct choices themselves.

Presented at the 34th Annual Australian Poultry Science Symposium 2023. For information on the next edition, click here.