Sunday, December 11, 2016
New developments in layer hen feeding.
A new method has been proposed that adapts the normal behavior of the hen to the requirements of modern farming. A single diet offered during the early hours of the light period with some source of calcium top-dresses during the afternoon is the standard feeding program for layers worldwide. A new method has been proposed that adapts the normal behavior of the hen to the requirements of modern farming. This method, called split feeding, is based on the principle that two feeds can be offered, one in the morning and another in the afternoon, at different quantities and with different nutrient composition. The morning feed focuses on the protein and energy requirements of the hen, whereas the afternoon feed focuses on the calcium requirement that coincides with eggshell formation. In preliminary studies, hens in split-feeding regimens consumed slightly less nutrients and eggshell quality remained strong or improved. Thus, not only was normal feeding behavior allowed, but profitability increased if we discount the extra cost of logistics for the second feed. This reduction in nutrient intake can have further positive consequences in terms of reduced nitrogen and phosphorus excretion and less stress on the hen coming from the excessive consumption of calcium needed to sustain eggshell quality, especially during the late laying period. This feeding programme results in a more profitable egg production through reduced cost of production, improved eggshell quality, increased number of marketable eggs and improved performance under sustainability criteria. Laying hens lay the majority of their eggs during the morning (Etches, 1986; Larbier and Leclercq, 1992). The interval between two successive ovipositions is about 24 hours or slightly greater (Keshavarz, 1998). After oviposition, the subsequent ovulation occurs about 30 minutes later. During the first four hours, the egg white is formed. Thereafter, the egg moves through the shell gland and the shell is deposited around the albumen during approximately the next 20 hours (Larbier and Leclercq, 1992). This shell formation mainly takes place during the evening and night. The requirements of laying hens for amino acids, energy, calcium and phosphorus do not remain constant but vary during the day. This depends on the hen's physiological needs for formation of the various components of the egg. Current methods of feeding laying hens with one diet with constant levels of nutrients may not result in optimal utilization of the nutrients (Chah, 1972; Leeson and Summers, 1997).When birds are offered diets that allow self-selection of nutrients, there is an increased intake of protein and energy observed in the morning around time when the egg is produced. The intake of calcium is higher during the later part of the day. In a study by Chah (1972) in which hens were offered diets that allow self-selection of nutrients, the total daily intake of protein was 11 per cent lower, while intakes of energy and calcium were eight per cent and 26 per cent, respectively, lower than hens fed a single, normal diet. This suggests that the hen is using the energy, amino acids, calcium and phosphorus more efficiently by consuming these nutrients at moments of the day when the requirements are high. Therefore, the current practice of providing hens with only one diet might not be an ideal approach for optimal utilization of nutrients. Nutreco R&D developed a new feeding programme which shows that Split Feeding offers the following benefits:1)More profitable egg production by reduction of production cost. 2)Improved eggshell quality and increased number of marketed eggs. 3)improved nutrient efficiency and sustainability. see