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Testing incubated eggs for embryo development

EmbryoSometimes it is necessary to test the incubated eggs for fertility. If large numbers of infertile eggs are incubated, they can be found and discarded, and the extra space used for additional eggs. This test will not injure the young embryos and is reliable for eliminating eggs that will not hatch.

Make a tester or candler by placing a light bulb and fixture inside a cardboard box. Cut a small, round hole in the top or side of the box, and let a narrow beam of light escape from the box. You can see the internal features of the egg by placing it against the hole. A darkened room makes testing easier.

The eggs are normally tested after 4 to 7 days of incubation. Eggs with white shells are easier to test and can be tested earlier than dark shelled eggs. Two classes of eggs can be removed on the basis of this early test, "infertiles" and "dead germs." "Infertile" refers to an unfertilized egg or an egg that started developing but died before growth could be detected. "Dead germs" refers to embryos that died after growing large enough to be seen when candled.

An "infertile" appears as a clear egg except for a slight shadow cast by the yolk. A live embryo is spider-like in appearance, with the embryo representing a spider's body and the large blood vessels spreading out much like a spider's legs. A "dead germ" can be distinguished by the presence of a blood ring around the embryo. This is caused by the movement of blood away from the embryo after death.

If you are not sure whether the embryo is alive, place the egg back in the incubator and retest later. A second test can be made after 14 to 16 days of incubation. If the embryo is living, only one or two small light spaces filled with blood vessels can be seen, and the chick may be observed moving.

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Dressed in a pink T-shirt and blue jeans, broiler grower Teresa Dyess stands next to two wagon wheels in front of a barn on her family farm.
Filed Under: Women for Agriculture, Poultry October 20, 2017

In three days, Teresa Dyess shifted her business focus from produce to poultry.

The change began two years ago with an offhand remark from her husband, Joe Dyess.

 “He told a broiler grower in Wayne County we wouldn’t mind building pullet houses because we wanted to diversify our farm,” she said. “We didn’t think any more about it, and then the next day a poultry processor called and offered us a contract. A banker came the next day, and everything fell into place.”

Lanette Crocker, coordinator for the MSU Extension Service in Wayne County, said Teresa Dyess’ adaptability has helped her maintain success through the farm’s transition.

Hen flock inventories grew after the poultry industry recovered from the 2015 avian influenza outbreak, increasing the number of eggs on the market and driving down the price. (Photo by MSU Extension Service/Kevin Hudson)
Filed Under: Poultry August 4, 2017

RAYMOND, Miss. -- Mississippi's poultry industry remains healthy with a strong demand for broilers and a positive outlook for the remainder of 2017.

Filed Under: Avian Flu March 30, 2017

STARKVILLE, Miss. -- All Mississippians who raise any species of poultry are being urged to follow strict biosecurity practices and review new requirements regarding sales and exhibitions.

Tom Tabler, poultry specialist with the Mississippi State University Extension Service, said that while avian influenza is not a threat to human health or food safety, an outbreak would endanger backyard flocks and the state’s nearly $3 billion commercial poultry industry.

Choosing the right breed of chickens for a backyard flock is an important decision. From left, Tripp, Luna and Charlie Sanders examine chicks for sale March 8, 2017, in Starkville, Mississippi. (Photo by MSU Extension Service/Kat Lawrence)
Filed Under: Poultry March 16, 2017

STARKVILLE, Miss. -- Families willing to host a flock of feathered friends reap the benefits of fresh eggs delivered daily just outside the door.

What started several years ago as an underground "urban chicken" movement has become much more common and widely accepted. Today, raising backyard chickens has gained popularity nationwide, boosted by interest in locally grown foods that avoid the energy use and carbon emissions typically associated with transporting food.

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