Research published by the University of Athens in January 2023 demonstrates how a gut agility activator impacts productivity in laying hens and cellular adaptive pathways in the gut and ovary. The insights gained are valuable in achieving a greater understanding of how nutrition can transform the power egg producers have over the ability of their flocks to reach high performance potential in a sustainable way.
The egg production industry has made great strides in improving productivity per hen and reducing the environmental impact of egg production. However, many flocks are still operating below their performance potential. The reason is that there are factors impacting the length of productivity in birds, and these are difficult to control by the producer under commercial conditions. This leads to the need to find solutions that can help control the response of the bird to a variety of stressors in such a way that high productivity, egg quality and well-being can be maintained for a longer period.
A better understanding of the underlying mechanisms affecting response outcomes in the bird and how these can be influenced by nutritional means can pave the way for more advanced nutritional strategies to help maintain productivity and well-being in birds for extended laying cycles. This would have positive implications in terms of further accelerating the progress made in the economic cost and environmental footprint of egg production.
Under commercial conditions, birds are exposed to a variety of stressors, including changes in diet, a rise in ambient temperatures, xenobiotics (including mycotoxins) in the feed and the stress of high productivity. All of these factors have implications for long-term performance and well-being, as well as the quality of the eggs produced. This means there is a performance gap that can only be closed if there are ways to support the bird to respond to stressors in more efficient ways or if the bird itself becomes more resilient through genetic selection.
In a commercial environment that is increasingly experiencing a shortage of labour on farms and pressure to reduce the cost and environmental footprint of production, laying hens that require little attention and still maintain productivity for longer have a real advantage.
Oxidative stress is a well-known factor that affects the long-term health and productivity of key organs for egg production in the laying hen, i.e. the ovary, gut and liver. It is the result of an increased accumulation of reactive oxygen species (ROS) in response to stressors that the body’s own defence mechanisms are no longer able to counterbalance. Understanding the underlying mechanisms provides opportunities to find ways of influencing them, and is supportive of closing the gap and achieving performance potentials in laying hens.
Oxidative stress is one of the main causes of ovarian ageing, which is linked to a decline in ovarian function and affects egg production and quality as laying hens get older. Highly productive laying hens are more vulnerable to oxidative stress and ovarian ageing due to rapid daily ovulations.
The laying hen’s capacity to mitigate oxidative stress is critical for maintaining egg production and health, especially in the pre-peak period of laying.
Two pathways are essential for cellular protection, namely the aryl hydrocarbon receptor (AhR) and the nuclear factor erythroid 2-related factor 2 (Nrf2). The Nrf2 pathway is responsible for the adaptive antioxidant defence and the AhR is responsible for detoxification. A reduction in productivity and intestinal health in chickens in response to stress factors such as heat stress and mycotoxins has been associated with an increase in AhR pathway-related genes and a decrease in the expression of Nrf2-related genes.
*Extracts of data published by Anagnostopoulos, et al (2023) and Brouklogiannis et al (2023).