Lohmann Hatchery Guide

5 5 LOHMANN TIERZUCHT › MANAGEMENT GUIDE HANDLING HATCHING EGGS The hatching eggs are not only eggs, but they contain living embryos with all the genetic potential inside that LOHMANN TIERZUCHT GmbH has combined over many years of strong selection. For good genetic transmission we need to guaran- tee the best condition of these embryos, and the first step is to have good hatching eggs: this is a crucial point. Many factors can influence the quality of hatching eggs: › › Health condition of parents stock flock › › Age of the parents’ stock › › Feed quality, water quality › › Medication treatments › › Type of housing and climate control, temperature › › Percentage and quality of male, spiking of male The above factors determine the quality of our eggs in terms of the lay, the uniformity 1 Good egg; and some negative examples: 2 Bad shell colours, 3 bloody, 4 plume, 5 malformed, 6 dirty 1 Good egg; and some negative examples: 2 under-sized, 3 malformed, 4 plume, 5 dirty, 6 bloody in size, the eggshell quality, the nutrients and maternal antibodies transmitted, the albumen and yolk percentage composi- tion and the fertility. › › Cleanness and condition of nest › › Collecting of hatching eggs › › Disinfection of hatching eggs › › Storage and managements of eggs The above factors determine hygiene sta- tus and the capacity of embryos to survive in storage. In the deposition, the temperature of the eggs is around 40 °C and they cool down considerately after. The surface is slightly wet: “cuticle paint isn’t dry and fixed”. At this moment, our eggs are cooling down to the surrounding temperature, which causes contraction. This means that air enters the eggs through the pores (in vari- able amounts according to breeder, age and eggshell quality) and creates the air cell. This is a very critical point in time, and our goal here is to minimise the number of microbes which enter the eggs. For this reason, it is very important that eggs are laid in as clean a nest as possible. Our external disinfection processes cannot kill all microbes, especially aspergillus spores, which may enter at this time. Only the dif- ficult and high risk process of dipping with special pressure machines and special products can kill all “visitors” which enter the eggs through the shell and mem- brane; some hatcheries use this treatment for floor eggs. Floor eggs are not considered hatching eggs, as they are already contaminated after having been in contact with the farm floor and with possible excrements, where the proportion of E. coli and other bacteria are relatively high. For this reason, Selection and management of hatching eggs