A Case for “Closed” Genetics in Yard Birds

From the onset of our layer operation we planned to implement a concept that Polyface Farms had employed with the genetics of their forage-based rabbits; line breeding, or “closed” genetics.

The concept is rather simple and straight forward… begin with a specific population of animals and do not allow any outside genetics to enter that population. The objective is to produce over multiple generations a farm-specific breed which is hearty, highly productive and carries particular strengths against the bacteria, parasites, diseases, climate and predation of the micro-environment that makes up our farm. It is an expensive experiment in that one has to allow nature to do her culling in order to find where those strengths lie within the population.

For our egg production we began with 225 birds (200 hens and 25 roosters). We purchased seven heritage breeds of chicken. We were looking for specific traits to impart within the flock, namely heat tolerance (after all our farm is in North Texas) and laying rates. We wanted breeds capable of producing 300 eggs a year. We chose: Rhode Island Red, Speckled Sussex, Black & Gold Sex Link, Buff Orphington, White Leghorn and Black Australorp. These represented the first generation of our egg layers, after which we closed the door to any new outside genetics.


Hunter Carter with one of his “girls”.

Over the first 18 months we experienced the expected higher losses, losing close to 50% of our flock. Some of the loss was attributed to our learning curve and management practices. We have always had small backyard flocks, but there are plenty of new dynamics with a larger flock. We also lost some to predators, but this is also part of the process… one bird leaves the coop looking up while another leaves looking down. The hawks take advantage of this weakness. For the record, we do attempt to protect our flock from every predator we can, but nevertheless, this natural loss does serve to refine the flock and naturally reduces a population through attrition of weaknesses.



We are now on our third generation of birds. Our hatch rates are up to 85% and in our latest generation we have had a mortality rate of 0%. Albeit, the birds are only 2 weeks old, but they are proving to be hearty in every way. They were running within just a few days, sparring, flying and roosting on our lower nesting box roosts within a week. They have a vigor, strength and pep we have not seen in any of our previous generations.

In order to keep up with egg demand we have now consolidated all of our laying birds into a larger operation. This new operation is in essence a farm within our farm owned by Hunter Carter, affectionately dubbed “Hunter’s Huevos“. This operation will be able to grow up to 600 birds and supply Cartermere with 35-40 dozen eggs per day. The only genetic factor yet to be seen is our laying rates. We are currently at 57%, however this is not too bad for the heat of our summer months, and we currently have a number of pullets still beginning to lay so rates continue to tick up each day.

Through this process, in 10 years we hope to have a fairly standardized “mutt” layer which is a heavy producer and extremely hearty for our farm. We’ll provide an update in a couple of years on our progress.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s