They worked the kinks out of the process over a series of years. They discovered, for example, that it was best to collect semen from turkey toms once per day, though one could try as often as twice per day. If they waited two days, they got the "maximum quantity at one collection," but not enough to make up for skipping the off day. They also tried giving the toms massive quantities of vitamins to supercharge their sperm production, but to no avail.

And on the receiving end, they found the right "dosage" of semen to achieve good fertility. That turned out to be 0.1cc of semen once per week from a mix of males (to offset any poor performers).

Along the way, they also tried to create chicken-turkey hybrids by inseminating chickens with turkey semen and vice versa. It didn't work, but their dream sort of lives on in the form of the turducken.

The process spread fairly slowly, at first, but it was widespread by the 1960s and the introduction of the Broad-breasted White breed that now dominates the market.

What was the actual process of insemination like? Andrew F. Smith wrote a great academic work called The Turkey, which provides the following very detailed description:

Although most turkey processing operations have been industrialized, the process of insemination must be done by hand. First, semen is collected by picking up a tom by its legs and one wing and locking it to a bench with rubber clamps, rear facing upward. The copulatory organs are stimulated by stroking the tail feathers and back; the vent is squeezed; and semen is collected with an aspirator, a glass tube that vacuums it in. The semen is then combined with "extenders" that include antibiotics and a saline solution to give more control over the inseminating dose. A syringe is filled, taken to the henhouse, and inserted into the artificial insemination machine. A worker grabs a hen's legs, crosses them, and holds the hen with one hand. With the other hand the worker wipes the hen's backside and pushes up her tail. Pressure is applied to her abdomen, which causes the cloaca to evert and the oviduct to protrude. A tube is inserted into the vent, and the semen is injected.

So much food marketing focuses on the production conditions (organic, free-range, certain types of feed) but so little of it focuses on the thing that matters the most: the genetics of the birds involved.

In 2007, poultry scientists conducted a remarkable study. They took a line of turkeys housed at Ohio State that had not been selectively bred over the last 40 years. That is to say, the turkeys had the genetics of commercial turkeys from 1966.

Then they fed the old-genetics turkeys and modern breeds the same diet, one often used in 1966. The old-line turkeys reached 21 pounds. The modern turkeys grew to an average of 39 pounds, and did it quickly.