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Goeie naand van Bethal
Hier is 'n kort oorsig van die Boran en sy genetiese samestelling.
Origin of the Boran
Introduction - Early domestication of cattle
Early archaeological evidence suggests two centres for domestication of cattle. The humpless Taurine cattle were domesticated 8,000 years ago in what is now Turkey and about 6,000 years ago the humped Zebu cattle were domesticated in the Indus Valley, Pakistan.
Introduction of European Bos Taurus cattle to
Rock art and archaeological evidence in the
Domestication of cattle in
In the 1980s, archaeologists Fred Wendorf of Southern Methodist University in
Introduction of humped cattle in Africa
The earliest evidence for humped cattle on the continent, provided by Egyptian tomb paintings of the XIIth Dynasty, do not appear until the second millennium BC, which suggests that the Egyptian civilization may have played a role in the introduction of Zebu into the continent. Today, most modern breeds have an appreciable Zebu ancestry, which attests to a major secondary introduction. Hannotte’s research found that the genetic signature of the Zebu breed was most prominent in cattle in the Horn of Africa. From this, Hanotte’s team concluded that Zebu were introduced primarily though sea trade rather than by walking into
This theory is supported by the traditional view that introduction of the humped Zebu Bos Indicus cattle is believed to have occurred in two waves: the first one is thought to have been about 1500 BC (Epstein 1971), although Marshall (1989) provides evidence suggesting existence of Zebu cattle in Africa as early as 2000-1788 BC; the second wave, associated with the Arab invasion of Africa, occurred from about 699 AD (Epstein 1971).
Cross-breeding in
Previous studies of mitochondrial DNA variation indicate that all African Bos Taurus and African Bos Indicus share the same African set of Taurine mitochondrial DNA haplotypes. This suggests that the pattern of Zebu influence on the African continent was a process of introgression rather than replacement of African Taurine cattle with unmixed Asian Zebu.
These processes may have taken place over millennia, perhaps starting with the initial introduction of Zebu to the continent. However, the introgression occurred after the initial migration of B. Taurus herding into western Africa, as indicated by archaeological data showing an earlier presence of Taurine cattle in this region and as supported by the presence today of West African Bos Taurus breeds that lack any Zebu ancestry. It is also thought that a major wave of Bos Indicus introgression may have started with the Arab settlements along the East Coast of Africa from about the end of the 7th century AD. Part of the subsequent inland dispersal of B. Indicus probably followed more recent pastoralist movements such as those of the Masai in
Since their arrival in
Up to now, the substantial Zebu background present in most African cattle has prevented unravelling the pattern of earlier Bos Taurus movements within
The pattern and the chronology of subsequent domestic cattle dispersal within the continent are also unclear. The origin and history of the early dispersion of African pastoralism westward and southward in the continent remain largely unknown, as does the pattern of the introgression of Bos Indicus, which is known to have influenced the majority of cattle populations in
The history of African pastoralism explains the contemporary genetic composition of African cattle. Domesticated within the continent but genetically influenced by the centres of cattle domestication in the
Summary
To summarize:
Cattle were domesticated in 3 parts of the world:
• Bos Indicus (Zebu cattle)domesticated in the
• European Bos Taurus domesticated in eastern
• African Bos Taurus domesticated in the eastern Sub-Saharan area 8000 BC
Cattle were introduced into
• European Bos Taurus
- the first introduction was hump less Taurine Hamitic Longhorns (Bos Taurus) and they arrived in the Nile Delta around 6000 BC,
- the second introduction, that of the Taurine Shorthorns (Bos Taurus) supposedly occurred about 2750- 2500 BC
• Bos Indicus
- the first introduction of the humped Zebu Bos Indicus cattle was as early as 2000-1788 BC;
- the second introduction, associated with the Arab invasion of
• African Bos Taurus
Domesticated in
GENETIC MAKE-UP OF THE BORAN
Through DNA sampling Hanotte et al have analyzed the genetic make-up of the Boran and it consists of the following genetic proportions:
• European Bos Taurus - 24%
• Bos Indicus - 64%
• African Bos Taurus - 12%
The Boran developed in eastern
“True resistance to disease is a complicated matter. For practical purposes, a smooth coat and motile skin provides the Boran with a useful degree of protection against tick and buffalo fly infestation. “Boran recovers from Foot & Mouth Disease faster than exotics, and suffers less damaging after effects.
“One genetic feature which seems clear is that cattle of Bos Indicus type are naturally more resistant to ECF than Bos Taurus type”. (AD Irvin and M P Cunning-ham. East Coast Fever, Diseases of Cattle in the Tropics, Ristic & McIntyre). “The Orma Boran has been shown to have a degree of trypanotolerance.” (R Dolan, Nairobi 2001) “A survey of eleven commercial ranches in Kenya shows that calf losses are in the order of 3.5 %, while losses from disease in older cattle are as low as 1% of the herd.” (quote BCBS) “As with all Zebus, the Boran has good heat tolerance. The sweat glands are more numerous and are larger than those of Bos Taurus and the skin surface is in-creased by the presence of extra folds...” (MacFarlane, 1964) Dark skin pigment protects against sunburn. Trials in Kenya (D. Robertshaw & V. Finch, Nairobi 1973) showed that B. Indicus has a relatively lower metabolic rate than B. Taurus and under heat stress there is less metabolic heat to be dissipated and the shiny coat reflects a high proportion of solar radiation.
- While European cattle stop eating and seek shade during the heat of the day, the Boran continues to graze. Under demanding conditions where cattle have to be penned at night because of stock theft or predators, this is a plus point for the Boran.” “Animals with Boran genes have a relatively low maintenance requirement. This was substantiated in a re-cent study at the
Being adapted to hot dry conditions, the Boran, with its lower maintenance requirement has a better chance of surviving droughts than Bos Taurus breeds. The Boran cow will cease lactating in adverse conditions, letting her live to conceive again when conditions improve.
European Bos Taurus:
As the European Bos Taurus are bigger framed animals and in general more beefy than Bos Indicus animals one can see the better beef attributes of the Boran (even though it is a small-medium framed breed) compared to other Bos Indicus and African breeds. One can clearly see that the general width of the Boran, from the chest through to the wide pin-bones, originates from the Bos Taurus genes in the Boran. This not only helps to produce more beef, but the wide pin-bones have an added advantage for ease of calving.
African Bos Taurus:
These genes add another genetic dimension to the possibilities of crossbreeding the Boran with other African breeds. The Ndama is the only pure African Bos Taurus left in
LONGEVITY AND OTHER TRAITS:
The fact that nature has selected the Boran makes it a fantastic cattle breed to farm extensively with and still retain critical beef attributes. The way pastoralists and farmers have been breeding the cattle makes it that it has a range of good and interesting qualities. Since all cattle need to stick together in a herd and that they are always kept together in a herd, else lion and hyena will take them out. This is also of great value in SA as it is difficult for thieves to separate 1 or 2 cows from the rest of the herd and thus makes it much more difficult for them to steel. They must either steel the whole herd or nothing. If you need to locate and count the cattle to check on them, they are always close together and you won’t find separate groups or wanderers. This saves on labour and just makes farming generally easier ie. when you bring cattle in to dip, treat or wean. This attribute of herdability has even been shown in SA on F1-crosses and is therefore genetically inbred over the 1300 years and not only something they were trained in Kenya. For the same reasons Boran has an excellent temperament, especially if compared to other Zebu animals world-wide. However after saying that one must note that the Boran mother is highly protective to her calf and has shown to fend of lion and hyena to protect her calf. There are also no ways these pastoralists would treat their cattle and only the strongest will survive. The animals were bred by the laws of nature, survival of the fittest. “Boran cattle have developed adaptive traits of crucial importance for their survival. Some of these characters are: - Ability to withstand periodic short-age of water and feed, ability to walk long distances in search of water and feed and ability to digest low quality feeds.” (Haile-Mariam, et al. “Boran - indigenous cattle with potential” 1994).
Certain traits will cause longevity in the Boran. It is not uncommon to have Boran cows still breeding at 18 years of age and it has been documented that a 23 year old bull had a 64% pregnancy rate with a herd of 60 cows. Only then was he culled as a result of “low” pregnancy rate in his cows.
The functional efficiency of the sheath of the Boran seldom results in a prolapse and or infection. Firstly, the angle of the sheath points forward rather than downward. Secondly, the preputium (tip of the sheath) has a strong sphincter that contracts to close the tip of the sheath. This prevents protrusion of the lamina interna and sticks and thorns sticking into the preputium. Thirdly, the sheath contains an active preputial muscle around the sheath that will retract the sheath up against the body of the bull. The skin fold in front of the sheath will then act as protection to the opening of the preputium.
The Boran has a highly motile skin which is very sensitive to the slightest touch. When a fly, tick or midge irritates or land on the skin it will shake vigorously and the insect will less-likely bite into the skin and transmit a disease. The subcutaneous muscle of the Boran is very well developed and thick relative to other breeds. The Boran’s skin can shake even at the base of the tail. When looking at mixed herds of cattle including Boran it is clear that the tails are much more active deterring flies and other insects, which is also a proof of the skin sensitivity. Apart from the high concentration of sweat glands (as previously mentioned) the skin has a waxy secretion which is unpleasant for an insect to bite through. The hair coat is extremely short which provides less footholds for insects attaching and holding onto clumps of hair to get into position to bite into the skin of the Boran. Field studies have shown that Boran feeding in the same veld / pastures as other breeds have a much lower tick count. The glossy hair coat helps reflect UV / sunlight thereby protecting the Boran from the hot African sun and the likelihood of cancer.
Even though the Boran has a short hair coat it has long eyelashes which helps, together with strong eyebanks, to protect the eyes from, sun, dirt and very importantly the Moraxella Bovis eye infection. This has been frequently proven on farms where cattle are ranched with Blesbok - the European breeds are susceptible to eye-infection and close to no-infections in the Boran.
The Boran mother is a wonderful cow. She has lots of milk to raise a strong calf. The small Boran calf (23 -35kg) is very strong and in Kenya it is not uncommon for a young calf to have to walk 5-8 km to the boma where they sleep at night to protect them from being eaten by lion or hyena. The mother is very protective of her calf and will not leave her calf and get lost in the bush. Bottle teats are seldom present in the Boran breed and which means that calves don’t need any assistance to drink. The Boran cow raises a calf of above 45% of the mothers weight at weaning and it is the norm to raise calves of more than 50% of the mothers weight at weaning.
Uitreksel van 2006 Boran joernaal.
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