Agriculture Reference
In-Depth Information
white wool.” But we're not talking about just any black fl eece — there are so
many people now raising dark sheep that it takes a prime fl eece, especially
clean, to bring top price. There is also the competition from imported fl eeces.
Australia and New Zealand now have extensive herds of colored sheep and
export tons of their wool into North America.
The fl eece of most black sheep tends to lighten from year to year. This
may be disappointing at fi rst, but in the long run it becomes an advantage
because it gives a greater variation in color from a relatively small fl ock. So
in shopping for a black lamb, remember that however black she is at birth,
she probably won't stay that black but will lighten every year. Don't consider
the degree of darkness as the main factor in your selection. Look at the body
type and wool grade, which do not change and will probably be inherited by
her offspring. Refresh your memory about what to look for and what to avoid
(in earlier chapters), and place health above other criteria when selecting
your sheep.
With one or two black sheep to introduce the black genes, you can
develop a fl ock of dark sheep in a few years if this is your goal. The easiest
BACKCROSSING FOR BLACK
Once you get a black ram of a suitable wool type, use him to breed
a small fl ock of white ewes. Geneticists say that the offspring will
be “white, but carriers of the black gene.” However, in practice, we
have had people use one of our dark rams on their white ewes and
more often than not they got dark lambs.
The fi rst generation of this cross is called the “fi rst fi lial genera-
tion,” or F1. If the F1 ewes are bred back to the original black ram,
their father, this is called backcrossing. It produces a generation of
F2 lambs, and in theory there should be as many black lambs as
white ones, with all carrying the recessive black gene. This amount
of inbreeding is not likely to result in many birth defects, but it is
risky to continue breeding with the same ram to succeeding genera-
tions (such as the F2 offspring). By the time you get a good number
of your ram's granddaughters (the black F2 ewes) into your breed-
ing fl ock, you'd be well advised to sell him and get a different ram,
one that is not related to your sheep.
