THE DAMARA OF
Essay On The Genetic Variation Within The Breed
Dawie du Toit
Himba, an Herero-speaking people, settled during the 16th
century in North Western Namibia with their Sanga cattle, Damara sheep and
goats. This area
is today known as Kaokoland.
The Himba have a nomadic lifestyle and roam freely in search of
water and grazing for their livestock.
In the 19th century, missionaries and explorers became
aware of the Damara sheep which was and still is one of the main sources
of livelihood of the Himba. The
Himba have been described as
Africa's most successful pastoralists.
the centuries, the Damara survived a long and perilous migration through
, and its genes have to large extent been shaped by natural
Damara had to survive for many centuries without veterinary support in a
hostile environment and had to adapt to these conditions.
It was only in the middle of the 20th century that
commercial farmers became aware of the unique characteristics of the
Damara, realizing that the Damara can thrive in a wide range of
environments without expensive support systems.
Coat Colour of the Damara and its place in The World of Coloured Sheep
its wild progenitor, the Asiatic Mouflon, the Damara has an outer coat of
stiff glossy hair and a short woolly under-coat which grows only in
winter. This under-coat
is shed in summer.
Himba always considered the coat colour of their domestic livestock as
very important. The
different colours and patterns helped the owner to identify his animals.
There are also strict rules regarding the colour of livestock that
can or cannot be eaten by the various clans within the Himba people.
explorers who opened the trade routes during the 19th century
, were particularly struck by the different colours of the Damara.
The Swedish explorer, Andersson, 1856, gives us a vivid description
of the Damara:
have no wool, but a kind of short glossy hair (lying close to the skin)
covers the body. The
greatest peculiarity of these animals is their colour, which is of every
hue and tint.
into the coat colour genetics in sheep started in the 1920s.
During November 2004, I attended the 6th World Congress
of Coloured Sheep in
. The majority of the
presentations at the Congress dealt with coloured wool sheep.
The wool sheep breeds have been selected for centuries to produce
white wool, because white wool can be dyed any colour.
The coloured genes in wool breeds therefore in time became rare,
and are mostly present in recessive genes.
The selection for coloured wool sheep is therefore a long process.
There is, however, a market for naturally coloured wool fleeces
which are sold mainly to the handcraft industry at a premium.
At the Congress I met some of the world's foremost geneticists
with an interest in the coat colour of domestic animals.
I did two presentations on the Damara, which were very well
received by the over 200 Congress participants.
The coat colour of a sheep is controlled by a number of pairs of genes.
Each pair is situated at a specific position, called a locus
(Latin for "place" plural loci) on one of the various pairs of
chromosomes. Alleles are
the different genes (options) that can occur at a particular locus. At the
Extension locus there are two alleles.
If the dominant black
allele is present, the sheep would be black.
This allele is common in the Karakul breed.
If the wild allele is present at the Extension
locus the colours and patterns at the Agouti locus can be seen - in other words the dominant black gene
overrides the alleles of the Agouti locus.
The most dominant colour at the Agouti
locus is white/tan and the
most recessive allele is also black (due to the nonagouti allele).
So when one sees a black Damara it can be due to either the dominant
black allele at the Extension
locus or the nonagouti allele at the Agouti
locus. Between the
two extremes of tan and black at the Agouti
locus, are all the different patterns and colours of the Damara.
The basic colours produced by the alleles at
the Extension and Agouti loci are often modified
by genes at other loci. In the
white-woolled breeds, the effect of white/tan allele is
to change all black or moorit (chocolate brown) eumelanin to tan
phaeomelanin. Other genes then take over to dilute or
reduce the tan colour, or totally eliminate it so that you get a
completely white animal. It is
important to remember that white is not a colour, but rather the absence
of pigments. Since
there has not been a selection for white in the Damara, the tan colour is
Lundie of New Zealand who has studied and researched the coat colour in
sheep for almost 3 decades, was so impressed by the coat colour and
patterns of the Damara that he paid a visit to South Africa in July 2005.
He summarised his impressions of the Damara as follows:
more than 25 years I have been studying the genetics of coat colour in
sheep whilst running my farm. This visit to see the Damara sheep is my
first real contact with a hair sheep breed. Within the hair sheep, because
of the fibre type, the colouring shows up in a more vivid way as the
contrasts between the tan, black and white are more spectacular. This was
even more memorable as the breed has not been selected for any particular
colour and so there was this wonderful range of colours, patterns and
markings to be seen.
is presently writing a scientific paper on the coat colour of the Damara
and I hope to publish it shortly.
This should not only be of great academic interest, but should also
assist the farmer in managing his coloured Damara sheep flock.
Sponenberg, a Professor at the Virginia-Maryland Regional College of
Veterinary Medicine, in the
United States of America, also attended the Congress and delivered two papers.
His coat colour genetics interests include sheep, cattle, horses,
donkeys, goats and alpacas.
has had a look at numerous photographs of the Damara and he writes:
colours and patterns of the Damara sheep are part of the wonderful
heritage of this breed, and it is important to keep the variability of
colour into the future. Breeders can assure this by encouraging and
celebrating the variability of colour in the breed, instead of focusing on
a limited array of colours and patterns as is common in most breeds of
sheep. The variability is a key part of the heritage of the breed, and
managing this diversity is a key to maintaining the breed.
are therefore fortunate that the Damara has not gone through a colour
bottleneck, leaving the Damara with a wide genetic variation of beautiful
skin colours and patterns.
We look forward to Roger's and Phil's contributions to our
understanding of the coat colour of our domestic animals and their
suggestions for colour breeding strategies.
Damaras with striking patterns
our modern western livestock industry the emphasis is on productivity in
pharmaceuticals ensure further that domestic animals with less robust
genes survive and reproduce.
The Damara, on the other hand, is one of only a few sheep breeds in
Southern Africa that, over the millennia, walked all the way down
with their African pastoralists.
The Damara has in the process been exposed to the vagaries of
nature. This resulted in
a breed rich in fitness traits such as its high resistance to most sheep
diseases and internal parasites.
The new trend of "breeding for disease resistance" is therefore
easily attainable with a breed like the Damara.
general conformation of the Damara has also been shaped to a large extent
by natural selection and there is a striking resemblance between the
Damara and the African antelope.
The sloping rump of the Damara ensures that the ewes can lamb with
prominent withers and relative long legs of the Damara aid its mobility.
The vital and reproductive organs of the Damara are not so close to
the searing reflective heat of the earth in summer, thereby reducing heat
stress. It can with ease cover vast distance in search of grazing and it
can use its sheer athleticism to escape from predators.
At three months, most Damara lambs are almost jackal-proof.
The strong herd instinct of the breed affords further protection
for young and vulnerable lambs.
One can only surmise that a predator like the jackal finds it
rather intimidating to take a lamb from a flock of sheep bunched together
in a tight circle at night. The
strong libido of Damara rams, coupled with the fertility and good
mothering ability of Damara ewes, ensure that ewes produce a lamb every
eight months. A high
percentage of these lambs are weaned.
The sheer athleticism
of the Damara
is, however, the cumulative
effect of all these genetic traits in one breed that makes the
Damara one of the world's most valuable sheep breeds.
These traits can easily fall by the wayside if we do not select our
sheep within well-considered parameters.
The challenge for Damara breeders is to preserve these traits for
the future. The breed is
ideally suited for the harsh, extensive South African conditions