weight of a egg

It should weigh less because it loses water

http://www.eggincubator.biz/set-humidity.html

During the incubation process, the embryo’s weight loses continually. The lower the humidity is, the more the weight loss is. As for chicken eggs, the best weight loss rate until 20th day is 12%-13%, and with a daily weight loss rate of 0.6%-0.65%. Any weight loss rate out of this range requires a humidity adjustment. There are many factors affecting the weight loss of the hatching eggs. The weight loss may vary for different kind of species, or under different conditions. In term of the same species, under the same conditions, the egg with thicker shell lose less weight than egg with thinner egg shell, and that with less shell surface loses less than that with more egg shell surface. The egg with low ventilating ability loses less weight than that with high ventilating ability. Besides, the size of the ventilation fans, the wind speed, ventilation volume, environmental humidity could affect the weight loss of hatching eggs. Therefore, the best method to set humidity is to check the weight loss rate of the hatching eggs, so as to judge the appropriateness of humidity.​

 

Can you use weight loss as a method for determining chick growth and viability?