Laying persistency is a major trait currently being developed further in laying hens. The “long life” layer, which will be capable of producing 500 eggs in a laying cycle of 100 weeks, is on the horizon.
In Europe, the priority is to increase egg production by breeding for increased persistency in lay and stability in egg quality so that the laying cycle of commercial flocks can be extended to 90–100 weeks. Breeding programs are particularly focusing on improving laying persistency and egg quality at the end of the laying cycle.
Reducing cost of egg production
Economic reasons play an important role in taking this decision. It means less feed is required per egg. Keeping the birds longer will decrease the financial contribution of the 18-week-old pullet to the cost per table egg. Maintaining egg size and quality beyond 75 weeks and up to a target of 100 weeks can have a big impact on the profitability of a flock. The time required to reach the economic break-even of the hen has increased from 34 weeks in 1998 to 52 weeks in 2016. This indicates that longer production cycles are imperative in a tough economic climate.
More sustainable egg production
Longer laying cycles lead to a lower carbon footprint per egg. Furthermore, it was calculated that around 1 g of nitrogen could be saved per dozen eggs for an increase of 10 weeks in production (Bain et al 2016). This can significantly reduce the nitrification impact of increasing or maintaining production, which is especially important in nitrate sensitive areas.
More efficient use of resources and reduction of waste will help to reduce the environmental impact of egg production and preserve the environment.
First commercial flock achieving 500 eggs in 100 weeks
Free range laying systems are following the trend for longer laying periods. The case for extending free-range laying cycles.
Actually, the first commercial flock achieving 500 eggs in 100 weeks, was a free-range laying flock and was reported in June 2018. It involved a 40 000 Dekalb White flock based in Germany. A key success factor in this was that the farmer likes to learn new things.
How to get to 500 eggs in 100 weeks
A decline in egg numbers combined with a deterioration in shell quality are the main reasons for currently replacing flocks at or around 72 weeks of age.
The benefits of genetic selection for improved persistency in lay and stability in egg quality can only be realized if they are matched by improvements in hen nutrition and careful monitoring of the effects of this process on the health and welfare of the hens.
To extend the laying cycle of commercial flocks, long-term maintenance of the tissues and organs involved in producing eggs is required.
Nutrition supporting laying persistency
Genetic progress and longer production cycles have consequences for nutrition. Benefits of genetic selection for improved laying persistency and stability in egg quality can only be realized if they are matched by improvements in hen nutrition. There are three important areas that come to mind, when it comes to supporting laying persistence by nutritional means:
1) Careful management of feed/nutrient intake around start of lay and in early laying period
2) Maintaining organs that are important for egg production healthy, e.g. liver
3) Minimizing common stress reactions such as oxidative stress, inflammatory responses and reduction in feed intake to maintain birds healthy and efficient
Supporting birds to keep a positive nutrient balance in the first 10 weeks of lay will help provide a reserve for mid/late lay egg output and improved shell quality.
With older birds it is important to maintain liver health. Consider supporting liver function with relevant additives, such as choline and vitamin E. Adding certain plant extracts to diets has been shown to improve the antioxidant status in laying hens and can be used to prevent oxidative stress. This then also has the potential to prevent fatty liver hemorrhagic syndrome (FLHS).
Managing nutritional stressors
Monitoring mycotoxins in feed also plays a key role for liver health in layers, as mycotoxins will cause oxidative stress and damage to the liver. Laying hens are more sensitive than other poultry to mycotoxins. A longer life makes laying hens ideal candidates for chronic mycotoxicosis, caused by continuous exposure to low levels of toxins.
Poor bird health and environmental stress affect egg formation and the ability of the hen to maintain persistency. This can be aggravated by nutritional stressors in the diet, such as dietary changes, reduced nutrient digestibility, endotoxins, antinutritional factors and mycotoxins.
Nutritional concepts designed to support gut agility, increase the bird’s capacity to adapt to nutritional challenges and live up to its performance potential, particularly under situations of increased stress. Overall, they are a sustainable alternative to help reduce the use of antibiotics in poultry diets, whilst maintaining robust and efficient birds for consistency in the cost-effectiveness of diets at high performance levels.
Adding a product including phytogenic components with antioxidative power and designed for gut agility to the late laying period of a commercial ISA Brown parent layer flock, improved the persistency in lay compared to birds on a control diet.
Recommendations from breeding companies