Definition of ophthalmology for English Language Learners. medical : the study of the structure, functions, and diseases of the eye.
Pullet: Six Weeks to One Year. Young female chickens less than 1 year old that have fully feathered out and are about the size of large pigeons are called pullets. Expect your barred rock pullet to start laying eggs when she is about 16 to 20 weeks old. Once she begins laying, she should produce one egg every 25 hours â except during the cold, dark hours of winter when she may not lay at all -- until her first molt a year later.
Remember chickens lay eggs for the purpose of hatching. Chicks hatching in the cold of winter would have a hard time staying warm and thriving, so this is not a peak egg laying period. Genetically speaking, Barred Rocks and Rhode Island Reds are good laying breeds, but some are bred for show and others for production.