Where can you purchase a variety of fertilized animal eggs?
Check on line for Chick Hatcheries, many also offer hatching eggs besides chicks.
If you know what breed of poultry you want to raise do a search for breeders of that particular breed of bird.
If it is chicken eggs you are talking about you will find that the eggs that are for sale at the market are not fertilised. If you want fertilised eggs you will have to get them from some one or a farmer that supplies eggs for chicks. You can purchase hatching eggs FERTILIZED from many hatcherys across the usa
hens and ducks obviously lay eggs that have not been fertilized, as well as eggs that have. the eggs that have been fertilized will eventually become chicks. from the best of my knowledge, other birds do not lay eggs unless they have been fertilized through sexual reproduction. so yes, bird's eggs must be fertilized before they will become chicks.