Effect of protein and energy level in feed on posthatch chick performance
R. Molenaar*, I.A.M. Reijrink*, R. Meijerhof*, J.K.W.M. Sparla‡, P.J.A. Wijtten‡
*HatchTech BV, Veenendaal, the Netherlands; ‡Provimi BV, Rotterdam, the Netherlands
Broiler chicks increase their body weight approximately 50-fold within 40 days of age. Because of this short life cycle, growth during the first week is important. This is also reflected in the positive relation between body weights in the first week and body weights at marketing (Nir and Levanon, 1993; Gonzales et al., 2003).
To start development of the bird posthatch, early feed is important, as is emphasized in different studies (Noy and Sklan 1999; Batal and Parsons, 2002; Uni and Ferket, 2004). The posthatch bird is anatomically complete, but digestive, immune and thermo-regulatory systems still need to develop (Maiorka et al., 2006). Besides utilization of exogenous feed, the residual yolk of chicks is also utilized during the first days posthatch (Romanoff, 1960; Noy and Sklan, 2001). Diet composition may interact with this utilization of yolk. The physiological conditions of posthatch chicks is in comparison to older chicks different and this might contribute to a difference in nutritional requirements. Optimal feed formulations for specifically the first days posthatch of broiler chickens are less known. Feed formulations are often based on average requirements for a longer period, and therefore not necessarily optimal for the first days posthatch. Download the entire article via the button below.