Egg Break Out

One method of determining if your birds eggs are fertile for incubation can accomplished by means of break out. Of course you can not incubate the eggs once they have been cracked open however, this will give you an idea if your birds are laying eggs which are fertile. One may also use break outs to help determine which birds have low fertility/reproductive problems. The break outs are done with unincubated fresh eggs.

Below is a fertile egg. Note the deep color of the yolk. Located at the end of the dark marker line is a small light dot with a unbroken, clear(not muddy or jagged) circle around it. I call it a "bulls eye".

Below is an egg which was fertile but the grem is dead. At the end of the dark marker line the light clouded area extended beyound and around the "bulls eye" is the tell tail sign it has expired. I suspect, due to this egg having been in the nest for a few weeks. A result of temp fluctuation and improper storeage; as one can see old eggs are not good for setting. This was the lure egg used to keep the birds laying in the same spot.

This last egg is not fertile, AKA true infertility. Note the light color of the yolk, not as deep/bright as the fertile egg(s). One can see the single small light dot (blasdisc) which has not been fertilized at the end of the dark marker line. If this egg were fertile there would be a ring around the white dot.

Though I may use unscientific terms such as "bulls eye" instead of blasderm, and although I can't spell worth beans ... I hope the photos and this page help those seeking to determine fertility in their flock(s). I'm no photographer either howver, I believe I got that part correct. [smile]

Additional detailed info on egg break out analysis for hatchery QA and analysis of poor hatches Go TO: UC Davis animal science pages There are photos, correct usage of terms and detailed information on break outs. They also have a break out video for sale if you wish to purchase it. They used to have a poster w/ pix as well, not sure if they still offer it.

A couple more egg break out photos at Ohio States website.

Another source of break out info U of GA Nice detailed write up of the procedure.