38 38 Pre-lay diet Transition period: the onset of lay From a nutritional point of view, pre- lay feed is a compromise phase-feed that contains an intermediate level of calcium allowing a smooth transi- tion between a developer diet (low in calcium) and layer diets (high in cal- cium) helping to support feed intake and improving uniformity. A maxi- mum of 800–1000 g is recommended before production reaches 5 %. During this period, a blend of coarse (3 –4 mm ø) and fine (1 –2 mm) calcium carbonate particles is ad- visable. A typical ratio would be 50 –60 % coarse and 40– 50 % fine. Transfer and the onset of production is a very stressful period, so it is vital that an adequate supply of nutrients is available and feed intake capacity is sufficient to meet all demands at this time. Transfer itself brings many stresses which will put a demand on metabo- lism: › Loss of body weight at transfer ( sometimes preceded by vaccina- tion). › Adapting to a new environment in the production house (often influenced by the set up in the rearing house). › Development is still ongoing dur- ing this period with the emphasis on the reproductive organs and formation of the medullary bones. › Egg production increases. Very often, during this period, a re- duction in feed intake is seen, lead- ing to a suboptimal nutrient supply. At this point, it is advisable to avoid any sudden changes in raw material composition or feed consistency that may further enhance the reduction in feed intake. Even though hens can compensate to some extent the balance between nu- trient requirements and feed intakes, we recommend implementing a slight increase in the nutrient density of the feed. In some circumstances, crumb or pel- leted feed can be an option to help maintain nutrient intake, bearing in mind that some of the advantages of using mash feed will be compro- mised, like gizzard functionality and gut health maintenance. Avoid increasing the number of feed distributions under low feed intake situations, as this can lead to selec- tive eating which can lead to further nutritional imbalances. Especially when feeding non-homogenous mash feed. A four-phase feeding program includ- ing starter, grower, developer and pre-lay diets is recommended. A pre-peak diet is proposed for that LOHMANN TIERZUCHT › MANAGEMENT GUIDE › FEEDING & NUTRITION Rearing Pre-lay Pre-peak till week 26 week 26–27 > 65 weeks Fine Calcium Coarse Calcium 25% Fine Calcium 35% Fine Calcium 50% Fine Calcium 50% Coarse Calcium 60% Coarse Calcium 75% Coarse Calcium 100% Fine Calcium Particle size: ø 3 – 4 mm less than 15 % of particles < 3 mm and less than 10 % > 5 mm Particle size: ø 0 – 2 mm Fine Limestone: average 1 mm Calcium particles 85% Coarse Calcium 15% Fine C.