Turkeys: The Good, The Bad, and The FertileBy
Turkey breeders will be able to single out fertile toms using a technique
that examines the swimming ability of a tom's sperm, an
Agricultural Research Service scientist
To measure turkey sperm movement, poultry physiologist
modified a test that Oregon State University scientists originally developed for
chickens. The test objectively measures what's called sperm motility--how well
sperm from each male can swim into a solution at body temperature. The test
mimics the environment the sperm encounter in the hen's reproductive tract.
Essentially 100 percent of the nearly 300 million turkeys produced annually
in the United States for consumption are the result of artificial insemination.
With advances in genetic selection, adult turkey toms can weigh up to 85 pounds.
A hen, however, weighs only around 20 pounds when she begins to lay eggs. This
size difference requires breeders to rely solely on artificial insemination for
reproduction in their turkey flocks.
For artificial insemination of turkey hens, sperm are generally pooled from
up to 10 to 15 males. So it's critical to know which males have the most viable
Information from these tests can be used to identify males that are very
fertile. Likewise, the test can be used to identify "losers." In the
past, most if not all semen evaluation tests have been much more effective at
picking losers rather than winners. This test does both.
The potential to pick toms based on a test that correlates sperm motility
with fertilizing potential could alter the way breeder toms are managed
throughout the United States, Donoghue reports. By sorting out infertile toms,
she estimates turkey breeders could save $5 million annually.
An in-depth story on this research appears in the July issue of Agricultural
Research magazine. The story is also on the World Wide Web at:
Scientific contact: Ann M. Donoghue is at the
Germplasm and Gamete
Physiology Laboratory, Bldg. 262, BARC-EAST, Beltsville, MD 20705; phone
(301) 504-8580, fax (301) 504-8546, email@example.com.