Selecting for Sustainability

D. Elficki of Aviagen International explained the concept of sustainability from the point of views of a broiler genetics company at the Australian Poultry Science Symposium 2011.
calendar icon 1 March 2012
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Sustainability is built on the pillars of economic, environmental and social issues. Aviagen, as a global leader in poultry genetics, understands that these issues cannot be viewed as separate but rather as inter-related and interlocking parts of a whole.

The broiler breeding industry is striving to produce a low–cost high–quality product available to all and that meets the ethical demands of governments and consumers, and reduces the impact of the industry on the environment. The use of advanced statistical techniques, medical technologies and direct testing of birds has been championed by Aviagen, amongst others. This has resulted in birds that have low levels of physiological issues, when properly fed and managed, with the lowest output of greenhouse gas (GHG) per unit of meat and the best feed efficiency of any farmed land animals.

Selection today goes far beyond issues such as growth rate, into areas of behaviour, welfare, resource utilisation and the requirement for long–term viability in breeding populations. It should be noted that factors such as management, nutrition and biosecurity can have much more dramatic impacts on individual flocks that genetics can.


Globally, the broiler industry consumes approximately 417 million parent stock (PS) per year, the equivalent of an estimated 58 billion broilers. The US industry alone now generates over US$44 billion per year in retail sales (USDA).

Over the years, selection for improved efficiency has been extremely successful. The cost of producing a pound of live chicken dropped from US$2.32 in 1934 to US$1.08 in 1960 down to US$0.45 in 2004 in today’s money (USDA poultry yearbook, 2006).

At the same time, within a flock, improvements in veterinary medicine, environmental control, nutrition and other management factors, have undoubtedly had dramatic impacts on bottom line performance, Havenstein (2003) stated that his results “indicate that genetic selection brought about by commercial breeding companies has brought about 85 to 90 per cent of the change that has occurred in broiler growth rate over the past 45 years. Nutrition has provided 10 to 15 per cent of the change.”

The challenge for this century will be to continue these improvements so that, as an industry, we make high quality animal protein available to all, but to do this in a way that is ‘sustainable’.

Sustainability – What is it?

Sustainability has become the watch word of the early 21st century. However, there are many definitions as to what sustainability is and many of these definitions are unclear or open to interpretation. Often the definition ‘to meet the needs of the present without compromising the ability of future generations to meet their own needs’ (World Commission on Environment and Development, 1987) is used. However, as common–sense as this may sound, it provides no benchmarks for us to measure ourselves against. The International Reporting Initiative, an organization that provides a framework for reporting “sustainability”, looks at three ‘pillars’ for sustainability; economic, environment and social. These three pillars are used in a number of models but one of the most frequently referred to is that of the interlocking and overlapping circles of influence as shown in Figure 1.

Figure 1. Sustainability model (Adams 2006)

Sustainability, to a breeding company, must encompass these three circles of influence. As a privately held company in a competitive market place, Aviagen must ensure that its products fit the variety of markets that exist worldwide, in order that wthe company is able to have a business that continues to be profitable for the future. At the IUCN ‘Renowned Thinkers Meeting’ (Adams 2006), it was noted that “Different strategies [for sustainability] will be needed in different contexts: no holistic ‘one size fits all’ plan will be effective. Los Angeles (L.A.) and Liberia are different places, with different challenges.” This is certainly true in the poultry industry. What is a key requirement for poultry in L.A. (high breast meat yield, with pathogen ‘freedom’) would be totally different to Lagos, where dark meat may be a preference but price is the primary driver.

In order for a breeding company to remain successful, the social and ethical issues associated with animal production have become increasing important. These are not just ‘welfare’ issues, although accumulations of leg health issues, poor immune responses, high feed intake or high outputs of waste product are today not considered suitable for a long–term sustainable breeding programme, nor for the individual birds that it produces. These are important ethical factors in consumer and central government thinking in many parts of the world but, as an industry we also face issues of human health – such as pathogen freedom and the nutritional factors in the meat we produce – and the availability of animal protein for human nutrition on a global scale.

Environmental traits will be increasing considered in breeding goals for the future but these interlink with social issues across many parts of the globe (Table 1). Free or cheap sources of non-vegetable protein are in decline. For example, the loss of capture fisheries is reducing an inexpensive source of protein in developing countries. Per capita fish consumption in developing countries, excluding China, declined between 1985 and 1997. As wild populations of fish and animals shrink and human populations become increasingly urbanized, the provision of low cost animal protein will be increasingly desired by consumers worldwide. Poultry, with its scalability, high throughput and excellent FCR, is an opportunity for people in both established and emerging markets.

Less than one per cent of the world’s fresh water is accessible for direct human use. If just the base flows of rivers and streams are considered as renewable and accessible, it has been estimated that this leaves as little as 11,100 cubic kilometres to supply 3,829 cubic kilometres of demand (World Water Assessment Program 2009). Whilst this might be underestimating the supply, when you consider that demand is expected to increase to 6,900 cubic kilometres by 2030, you can see why water availability is both a local and global issue. It has been hypothesised that the 2030, demand may be over 50 per cent of what is theoretically sustainable. Although it may appear that there should still be sufficient water available, a major issue is its distribution with 15 per cent of the world’s available water being in the Amazon, available to only 0.4 per cent of the population.

Land is becoming more expensive if not scarce. Peri–urban land previously used for agriculture is being utilised for urban expansion and industry. This will increase the distance our food supplies have to travel to reach us, with its knock–on effects of greenhouse gas (GHG) emissions, congestion and so forth. This has become such an issue that Dr Dickson Despommier (Despommier, 2010) of Columbia University has proposed vertical urban farms. Prototypes of these are already under construction in Tokyo and South Korea. This model precludes extensive forage systems for animal production but is well suited to the production of chickens, which require little floor space and can utilize (to some extent) waste products from crop production, whilst providing valuable fertilisers and a rapid feed efficient turnover of ‘crops’.

The publication of a report in the UK (DEFRA, 2008) indicated that of all the meat–producing livestock species, commercially raised broilers have the lowest GHG emissions per kg of meat produced. Genetic selection of broilers over the last 20 years has shown a reduction of GHG emissions of around 25 per cent, with this reduction predicted by the authors to continue for the next 20 years or so. Commercial geneticists feel that this is a very conservative estimate given the enhanced technologies available today and in the near future. Selection targets for efficiency, especially in feed conversion ratio and meat yield have primarily driven this reduction, at the same time as reducing the wholesale price of high quality, healthy animal protein to the customer.

Development of Breeding Strategy

Breeding strategies have never been developed in isolation. The breeding industry, as with all corporate entities, is required to produce products that are acceptable and desired by the end user. Therefore, feedback and consultation with direct customers, end–users and consumers has always been a key feature in developing breeding goals.

Due to the structure and nature of the breeding business, there is approximately fiveyears from a breeding decision being made in the breeding programme to the first effects of these changes being experienced in the broiler generation. Unlike a car manufacturer, the industry does not have the ability to make wholesale changes in direction overnight. Genetic change is not sudden and is often not greatly noticeable until some years of advancement accrue, much like compound interest. It is, therefore, crucial to the future success of the business to liaise effectively with policy–makers, scientists and lobby groups to best predict consumer issues in the future and to identify emerging issues from the field.

Within Aviagen, a major part of our global success has been the emphasis that has been placed on balance, not just in terms of performance traits, ensuring that the products are successful at all stages of the breeding pyramid but also by ensuring that we focus on the support traits for our birds, with this strategy now broadening to capture environmental and emerging ethical concerns. Although Aviagen is a global company, much of the cultural heritage stems from the UK. Europe in general and the UK, in particular, has always been a region that is a sentinel for future global feeling on animal welfare and environmental concerns.

Performance Efficiencies

Aviagen has long been a world leader in the use of technology to improve the feed efficiency of broiler chickens. For over 30 years, the comapny has used highly controlled individual pen tests to enhance FCR in its birds. This technique has almost halved the amount of feed required to generate a unit of poultry meat since the 1970’s.

Individual pens, whilst cost–effective and of high welfare standards, do not address the behavioural aspects of feed efficiency. In 2005, Aviagen started selecting pedigree chickens using performance testing stations in their breeding programme. These stations allow birds to be group–housed and demonstrate the behavioural aspects of feed intake and efficiency. This technology will allow Aviagen to make faster improvements in FCR, with improvement rates around 2.5 per cent per annum. This improvement rate is close to the predicted increases in world chicken meat output. This being the case, the industry will be close to truly sustainable with inputs reducing at around the same rate as growth.

Improving meat yields also play a part in ensuring long–tem sustainability. Using traditional conformation scoring along with ultrasound technology and information on the actual yield of siblings, Aviagen is able to increase yields at over 0.30 per cent per annum. The use of the brothers and sisters of pedigree birds for processing is invaluable in ensuring that muscle or skeletal deformities can be indentified in pedigree families quickly and those families selected against.

Global Focus

As a global supplier it is important to understand that Aviagen's customers and their consumers have different requirements and standards of nutrition, hygiene and management around the world. For many years, Aviagen felt it was appropriate to grow our pedigree birds to their maximum potential under essentially un–limiting conditions, in order to expose any underlying physiological issues. This allows selection from families that show no significant undesirable traits. The company still believes that this is appropriate, However, it understands that around the world, there are people unwilling or unable to achieve the levels of nutrition, biosecurity and management that are recommended.

Therefore, almost 10 years ago, Aviagen set up our sibling test, where brothers and sisters of pedigree birds are exposed to management and feeding practices in line with the bottom quartile of the industry. This exposes the chickens to lower input type scenarios, again potentially improving the sustainability, and ability of our stock to thrive under such conditions.

Increasingly robust chickens, in the face of disease challenge or management mis-step, has no negative implications for those with the finances or management skills to follow high input advice. However, with the high prices of corn and soy, along with the increasing cost and scarcity of other raw materials such as shavings in many parts of the world, a number of companies worldwide are choosing to reduce inputs in order to maintain wholesale chicken prices at recent levels. Associated with this moves towards lower energy systems, primarily from a cost control point of view, are becoming increasingly common. This does have the impact of potentially reducing GHG emissions although it will be important for breeding companies to breed increasingly robust lines to ameliorate any negative impacts on performance.

Improving physiological strength has no negatives for those choosing a lower input direction for their farming base but safeguards skeletal integrity and cardiovascular function, under all bar the most challenging of management or nutritional situations.

Since the late 1990’s, Aviagen has not utilised prophylactic antibiotics or coccidiostats in our breeding programmes, as the company believes that its stock should be sufficiently hardy to perform in their absence.

Physiological Function

Many campaign groups and welfare–orientated scientists have made claims as to the negative physiological health status of broiler chickens caused by commercial selection practices, discussing issues of leg defects, especially tibial dyschondroplasia (TD), amongst other syndromes (Cooper and Wrathall 2010).

Some groups have gone as far as to recommend or campaign for the end of intensive broiler farming due to these issues (CIWF, 2010). These claims may have been valid in the 1980s, when most breeding companies were using mass selection or selection index technologies in their programs. However, 20 years of continued focus on these areas, using traditional inspection methods, medical technologies such as X–rays, as well as genetic technologies that better understand the relationship between traits, has reduced these issues to very low incidences on effectively run commercial production facilities.

Whilst effective measurement of the reduction of these concerns is difficult, large datasets like those available from the Canadian Meat Inspection Service indicate dramatic improvements in both the underlying genetic susceptibility of modern broilers to these issues, and an increased awareness of the management requirements of these improved individuals. Today, most incidences of TD are associated with incorrect formulation of diets. One study that is often shown by welfare activist groups, carried out in Denmark (Sanotra et al, 1999) showed a 57 per cent incidence of TD in commercial broilers in 1999. Six years later, in a repeat of this study (Pedersen et al, 2005) the incidence had dropped to 0.7 per cent. In the first study, it was later reported that the diet had been deficient in calcium, which was most likely to have caused the TD issues (Laughlin, 2006). Even reports from the UK scientific community are now indicating that welfare researchers are acknowledging that significant progress has been made in a range of welfare traits, although there remain other issues. (Whitehead, 2010).

Figure 2. Condemnation rates in the Canada from ascites. Agriculture and AgriFood Canada (2010)

Further research and development into new issues associated with welfare and sustainability are being implemented globally. Breeders respond to emerging trends as swiftly as they can. However, due to the multiplication structure of the industry, there is a lag from when the issue is first selected upon until the first effects of these selections can be seen. This is sometimes perceived as a lack of concern, especially as when by its nature the industry is competitive and intellectual property needs to be maintained. For example, foot pad condition is currently talked of as one of the primary metrics of welfare in the newly enacted European Broiler Directive (Council Directive 2007/43/EC).

Selection to both improve foot pad quality and reduce the incidence of the conditions that can lead to this condition, have been underway for some years. However, due to genetic lag, there remains a requirement to manage birds effectively to improve ‘paw’ condition whilst the genetic improvements make their way down the generational pyramid.

Product Diversification/Biodiversity

Statements has been made that commercial breeding populations lack genetic diversity (Muir et al, 2008), and that the formation of commercial breeding companies and their subsequent selection strategies have directly caused this. All of the large commercial companies keep substantial populations within each ‘line’ to maintain variation and control inbreeding.

There has also been a move for many of the breeders to acquire more varied stock types to give more depth to their programmes and provide greater choice to consumers. In some, primarily, developed countries, there is a move away from standard commercially farmed chickens, to something that is perceived as higher ‘quality’. This is done by nutritional restrictions on ingredients; exposure to the range; organic nutrition; restriction on growth rates; etc. The demand stems from a small but significant percentage of consumers, to which producers are responding.

All of these strategies tend to reduce ‘sustainability’ through usage of greater amounts of feed and increased GHG production. They also increase cost. For the majority of labelling systems, Aviagen has a diversified product portfolio that can meet the criteria of the system and supply traceable, guaranteed health status stock for these production systems. Care should be taken that lower income consumers are not legislated out of eating chicken, as this remains one of the healthiest animal proteins available.

Future Potential

With the publication of the full chicken genome (Wong, et al, 2004), the inclusion of genomic technologies into commercial poultry breeding programmes has come a step closer to reality. All the current primary breeding groups are investing heavily into these areas. It is unlikely that the use of transgenic technologies (artificially moving genes from one individual or species to another, or removing genes) will be acceptable to the majority of consumers worldwide at present, so the focus is very much on the understanding of the function and effect of genes already present in the breeding populations.

This knowledge will be used to select more efficiently and effectively for traits of importance. The traits that will benefit the most from these technologies are likely to be the ones for sustainability, environmental impact and robustness, as these are traits often difficult or destructive to measure in a traditional breeding structure.

Currently research programmes looking at further resistance to ascites, more effective utilisation of water, avian influenza resistance, Campylobacter exclusion, amongst many others, are candidates for genomic research.


In developed nations, the percentage of household income spent on food can be as low as 7.4 per cent (USA). However, in less developed countries, this can be over 50 per cent (India and Philippines). The improvement of chicken production efficiency over the last 50 years, coupled with many other agricultural advances, has helped bring high–quality, low–fat animal protein within reach of all but the very poorest of individuals worldwide. Continued advances in genetics as well as the other associated improvements in optimisation of broiler production will bring chicken within the budget of all.

There is good evidence to suggest that the concerted efforts by Aviagen and other breeding companies have reduced the levels of physiological issues associated with modern, fast growing types of broilers. At the same time, improvements in absolute performance have greatly reduced the carbon footprint of the industry and will continue to do so.

Undoubtedly there will be emerging issues of welfare, sustainability and consumer ethics that will come to the forefront over time, which Aviagen is well placed to understand and react to. Genetic lag will continue to be an issue in these circumstances. It is important to understand that whilst selection for sustainability and welfare traits will continue, with additional power coming through genomics, management, nutrition, biosecurity and so on can have much more dramatic impacts on individual flocks in the field than genetics can.


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Further Reading

- You can view other papers presented at the Australian Poultry Science Symposium 2011 by clicking here.

March 2012
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