Incubation of eggs from our modern strains of chicken

摘要

Commercial incubators have undergone a variety of changes that have improved efficiency and reliability, but the basic design has not changed over the past 25-30 years. Equipment has not changed dramatically, but the same cannot be said for the eggsbeing incubated. The commercial incubator has its origins in the early 20th century and has undergone a variety of changes that have improved the efficiency and reliability of the equipment. However, it can be argued that the basic design of the incubator in 2002 has not changed over the past 25-30 years (perhaps even longer). For instance, the modern corridor-style, multi-stage trolley incubator is little different to fixed-rack machines manufactured in the 1960s. The technological improvements have mainly been concerned with increasing computerisation of the control of the environment within the machine. Incubators of a radically new design are rare. Since incubation equipment has not changed dramatically over the past 30 years, can the same be saidfor the eggs being incubated? Increasingly the importance of the strain of poultry being incubated is being emphasised in the hatchery industry. It is argued that the "high-yield" strains, particularly of broiler chickens, require different incubation conditions than the strains used in the past. Intuitively this has to be true but to what extent are these new strains any different from the strains of birds that preceded them? Furthermore, how do we know what to change to improve incubation conditionsand increase hatchability or chick quality?