Market pressures, growth in the cage-free market and bird management issues continue to challenge the egg sector. As feed price volatility continues and margins are eroded, producers and nutritionists need to find strategies to improve the efficiency of egg production.
One technique is to increase the number of weeks for which a flock is kept – more eggs for the same initial outlay; however, the main challenge with hens late in lay is maintaining persistency while controlling egg size and achieving egg quality requirements. With beak-tipping bans on the horizon for some, strategies to improve welfare and prevent injurious pecking are a priority.
Longer laying cycles
Maintaining lay persistency, egg mass and shell quality in late lay can have a significant impact on flock financial performance. Hens lay fewer, larger eggs and eggshell strength is reduced along with the quality of albumen. Egg size should be controlled and calcium intake optimized. Poor eggshell quality is a major cause of downgraded eggs (seconds), a function of reduced shell thickness and strength – due to less effective calcium metabolism.
As well as overcoming these issues, late lay management must ensure skeletal integrity is maintained and that birds remain on target body weight, well feathered and in good condition. While certain issues can be addressed once hens reach approximately 60 weeks, others need to be considered from pullet onward.
As birds progress through lay, calcium intake needs to increase, alongside a reduction in available or digestible phosphorus. To optimize calcium nutrition, it is important to consider the physical form and the time it is fed. Large particles are retained in the gut for longer, meaning they are available during the dark period.
Split feeding hens
The technique of feeding different diets at different times of the day is nothing new. However, interest in the technique is re-emerging with flocks kept in production for longer. The current practice of providing hens with only one diet may not result in optimal utilization of nutrients. Split feeding delivers the optimal supply of nutrients in order to meet the specific needs of the hen during the egg formation process. Two feeds are supplied at different times of the day:
- The morning diet is designed to meet energy, protein and phosphorus requirements for albumen formation, ovulation and oviposition.
- The afternoon diet is designed to meet requirements for eggshell formation, in particular higher calcium levels.
Laying hen requirements for amino acids, energy, calcium and phosphorous do not remain constant. Hens lay the majority of their eggs in the morning, and their nutritional needs for the various stages of egg formation vary throughout the day. When birds are offered a choice of diets, an increased intake of protein and energy is observed in the morning. Calcium intake, however, is higher during the latter part of the day. Shell calcification takes 15 to 16 hours – usually occurring overnight. Hens consume less nutrients overall, using them more efficiently when they match their requirements over the course of a day.
In split feeding trials, egg production was at least as good compared with a commercial feed, with a number of benefits observed, particularly later in the cycle. Experimental data shows that when flocks are kept past 90 weeks, the percentage of saleable eggs increased significantly (Figure 1). This was due to a 30 percent reduction in broken and shell-less eggs – hence a greater number of eggs that could be sold as table eggs. Further results show that egg shell weight and egg shell thickness increased by 1.3 percent (P<0.05). Leading to a 30 percent reduction in broken and shell-less eggs – hence a greater number of eggs which could be sold as table eggs. With a split feeding system, the laying hen is more able to exhibit physiological feeding behavior – adjusting its nutrient intake according to varying nutrient requirements throughout the day.
split-feeding-effect-egg-production Experimental data shows that the percentage of saleable eggs increased significantly in flocks kept past 90 weeks due to a 30 percent reduction in broken and shell-less eggs. | Trouw Nutrition
Split feeding also improves sustainability, with less nitrogen (10 percent), phosphorus (5 percent) and calcium (4.1 percent) excreted. This is thought to be due to a lower daily nutrient intake and their more efficient use. Split-feeding results in more profitable egg production due to reduced cost of production, improved egg shell quality, increased number of saleable eggs and greater sustainability. The caveat of this system is that two feed bins are required to deliver the two formulations, along with a feed weighing system and an automated system to change the feeds, meaning significant investment for existing housing systems and design considerations for those newly built.
Fiber, fiber, fiber
A lot is written about the importance of fiber in diets for all livestock and, when it comes to laying hens, it’s not just the gut that benefits but also the feathers. This key welfare indicator is particularly important as some countries look to ban beak-tipping. An increase in bird interaction inherent in cage-free systems can also increase the likelihood of vices developing. Both nutritional and management techniques are key to controlling issues such as pecking. By adding structural fiber to the diet, gut function is improved, increasing the potential for greater nutrient digestibility. Improved feathering also has a role to play in maintaining persistency and egg quality.
From commercial experience, there is no doubt that offering a free-choice source of fiber is beneficial to laying hen behavior. The use of straw bales has been common for many years, acting as a useful distraction for the birds to pull apart rather than pecking each other. The use of Lucerne that has been compressed and dehydrated into bales is becoming popular in pullet rearing and laying houses. Larger bales are placed on the floor, or smaller ones hung up or held in hay nets, which are regularly replenished. As well as a destructible enrichment, Lucerne bales help to fulfill birds’ need for fiber.
Bird wellness
The needs of a fully beaked bird are not inherently different from one that has been tipped. However, when faced with stressors, the potential for injurious pecking is greater. It has been said that fully beaked birds do not tolerate mistakes; nutrition and management needs to be perfect. To a lesser extent, the same could be said of the difference between intensively reared and cage-free laying hens. Feed structure is key, along with nutrient balance and enrichment.
Improving the economics of ‘cage-free’ egg production
Cage-free eggs are becoming a commodity, representing more than 50 percent of the market in countries like Germany and the U.K. In order for laying farms to remain commercially viable, strategies need to be found to improve the economics of production.
For longer laying cycles to be viable, diets need to be developed to meet the specific requirements of birds in late lay. It is then possible to improve lay persistency and egg quality while potentially reducing feed costs. A split feeding program that meets the dynamic requirements of egg formation can lower the total nutrient intake. Birds need to remain healthy throughout from a production and welfare point of view – particularly if their laying life is extended. Welfare, which ultimately affects productivity, also needs careful consideration. The use of strategies such as free-choice fiber sources, will also have an important role to play in future cage-free hen management.