Like many of you, we are always looking for information on the "how to's" of raising backyard chickens and explanations for "why" something occurs. While attending the Washington State University Poultry Institute annual seminar  - a handout by Alltech was available that showed  "20 Common Egg Shell Quality Problems".  

Here's five quality problems and possible causes: 

• Pale-shelled Eggs: the degree of brown color in the egg shell is determined by the quality of deposited pigment in the cuticle.  Causes: Infectious Bronchitis, Bird Age (older hen), High Stress in the Flock
• Wrinkled Eggs: eggs with thinly creased and wrinkled surfaces. Causes: Stress, Defective shell gland, Overcrowding. 
• Misshapen Eggs: these eggs are too small or large, round instead of oval, or differ from normal shapes. Causes: Immature shell gland, Disease (Avian influenza, Egg Drop Syndrome 76), Stress, Overcrowding
• Corrugated Eggs: Characterized by a very rough, corrugated surface, these eggs are produced when plumping is not controlled and terminated. Causes: Heat stress, Saline water, BIrd age, Poor nutrition, especially calcium and vitamin D3
• Pimpled Eggs: Classified by small lumps of calcified material on the egg shell, the severity of pimples depends on the foreign material present during the calcification process. Causes: Bird age, Strain of bird, Inadequate nutrition

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