Hair Sheep in the United States: Historical Perspectives
Eric
Bradford
Animal Science Department
University of California
Davis, California
"Hair sheep" is a term that until relatively recently
was not familiar to U.S. sheep producers and others in this country
working with sheep. Although sheep with little or no wool had been
known in parts of Texas since early in the 20th century, they were
unknown or little known elsewhere in the country until 1970 or later.
Such sheep originated in the tropics and are the type of sheep best
adapted to the tropics, especially the humid regions. Although virtually
none of the U.S. is in tropical latitudes, the existence of substantial
areas of the country with a warm, humid climate, plus an unfavorable
ratio of shearing costs to price of wool in most years, have led
to an increasing interest in the U.S. in these animals.
The first recorded introduction of hair sheep to the U.S. was a
USDA importation of Barbados Blackbelly animals from the island
of Barbados in the early 1900's. These sheep came to Texas, where
they were crossed with Rambouillet and Mouflon, with the resulting
stock sometimes referred to as the "Barbado" breed. The
second importation of hair sheep to the US was of "fewer than
10" Virgin Island White sheep from the island of St. Croix
in 1960; they were crossed with U.S. breeds to create the foundation
for the Katahdin breed, and no pure descendants were kept. In 1975,
3 rams and 22 ewes were imported from St. Croix by Utah State University,
and rapidly multiplied to become what is known in the U.S. as the
St. Croix breed. As indicated, these two breeds both came from Caribbean
islands. Hair sheep (including a number of breeds/types not yet
imported to the U.S.) are the predominant type of sheep in Caribbean
and northern Latin American countries, but all such animals descend
from hair sheep that came from West Africa one to two hundred or
more years earlier, presumably in connection with the slave trade.
The U.S. Barbados Blackbelly and St. Croix breeds have been evaluated
in crossbreeding trials with wool breeds in several locations in
the U.S. The results indicate that, compared to wool sheep, hair
sheep and, to a lesser extent, hair x wool crossbreds, in general
are: smaller at all ages and have lower average daily gains, have
carcasses with less subcutaneous fat but a higher % kidney and pelvic
fat, have higher fertility of both rams and ewes, are less seasonal
and lamb more frequently in accelerated lambing systems, have equal
or higher litter size, lamb without assistance, and have lower fecal
egg counts for common internal parasites.
More recently, semen and embryos of South African Dorper sheep
have been imported via Canada and Australia. Because of their larger
size and better carcass conformation than the St. Croix, they have
been used in some private flocks to grade up from a St. Croix base
to produce white hair populations. Nearly all if not all hair sheep
in the U.S. have some inheritance from wool breeds. This has the
advantage of broadening the genetic base of U.S. hair sheep populations,
which is very narrow in terms of breeds sampled and size of samples
within those imported, but usually results in animals that are not
completely free of wool.
Some challenges in developing successful hair sheep production
systems in the U.S. include increased sampling of hair breeds from
other countries, development of efficient means of breeding wool-free
animals from hair x wool crosses, utilizing the genetic potential
of hair breeds for resistance to internal parasites, and increasing
size/growth rates of hair sheep intended for traditional U.S. lamb
market channels.
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