Knowledge of Diet Nutrient for Laying Hens
Traditionally, diet nutrient concentrations decrease over time, with the notable exception of the need for more calcium. Thus, diet protein and amino acid expressed as a percent of the diet or as a ratio to energy decline as the bird progresses through the laying cycle. However this traditionally approach is now being questioned in nutrient content of successive diets is being tempered and/or delayed. Regardless of other nutrients, it is important to increase diet calcium level and to concomitantly decrease the diet phosphorus level as the bird gets older. The need for less methionine is partially related to the need for tempering a late-cycle increase in egg size since this is usually uneconomical regarding egg pricing and the fact that larger eggs have thinner shells. However, the ability to temper eggs size, while sustaining production, through use of less methionine is far from straightforward.
With variable feed intake, it is necessary to adjust the ratios of all nutrients to energy so as to maintain constant intakes of these nutrients. While it is impractical to consider reformulation based on day-to-day fluctuations in environment temperature, trends in feed intake associated with high versus low bodyweight, etc., should be accommodated in diet formulation. Precise knowledge of feed intake and the factors that influence it are, therefore, essential for any feed management program. The energy level of the diet will influence feed intake, although one should not assume the precision of this mechanism to be perfect.
April 29 2008 09:30 am | Poultry