Mohamed E. Mufarrih
Problems facing the sheep industry in the semi-arid zone
The sheep industry in the semi-arid areas of the Sudan has been hampered by water shortage, complicated grazing problems and a prevalence of disease and parasites. In recent years these areas have experienced successive periods of drought and considerable areas of grazing land have been partially decertified and migratory herds of camels and sheep have penetrated into the savannah belt for dry season grazing. In the centre of the semi-arid belt in the eastern and central regions and Southern Kordofan, expanding crop farming has encroached upon a large area of grazing land resulting in the expulsion of thousands of livestock.
The most critical period for range sheep in the semiarid zone of the Sudan is from February to the end of June, when the ambient temperature becomes hot and dry and range grazing is scanty and depleted of nutrients and vitamins.
Migratory sheep flocks spend the dry season near watering yards called “damar”. During winter months, when the ambient temperature is mild and the range contains some green fodder, herders can extend the watering intervals from ten to 15 days. After winter, grazing and climatic conditions become harsh and the watering interval is reduced to between three and five days.
In the central and eastern regions, where vast are-as of traditional grazing land have been converted into crop farms, many nomadic families have adapted themselves to a residential or semi-residential existence. Their sheep spend the dry season within or around the cropping areas and sustain themselves on crop residues. Encroachment on farms and damage to crops have caused a series of clashes between farmers and herdsman and security forces have frequently been called in to drive livestock away from the vicinity of farms. Once harvesting is completed, nomadic and residential livestock are allowed to graze crop residues, thus alleviating the feed situation. However, these residues are only able to sustain this large amount of livestock for about three to five weeks. The animals are then forced out so that the land can be prepared for the next cultivation. Most nomadic and semi-nomadic herds move to remote ranges and are sustained on the remnants and stubble of dry vegetation until the rains arrive.
With the advent of early rains, Desert sheep flocks are driven to ranges near their damar locality where fresh grasses and fortes are stimulated by early showers. These early grazings are commonly called “shogara”. The sheep recover their body condition very rapidly on shogara grazing and start dropping their rainy season lambs. By mid-July the rains fall heavily and the fresh vegetation reaches abundance level. Mosquitoes and other insect vectors force the sheep flocks to leave the damar localities and start the rainy season migration toward the north, northwest or northeast where the rains fall late and the vegetation is more tender and nutritious.
The Sudan sheep industry is also jeopardized by diseases and most losses can be attributed to helminth parasites. Although the damage inflicted by various parasites varies between localities, nematodes are more serious in the main sheep-raising areas. Nematode infestation flares up at the very end of the dry season and the early onset of rains. Heavy casualties occur among ewes when stomach worm infestation is complicated by anaemia. In the White Nile basin, schistosomiasis and fascioliasis cause great concern.
Tickborne diseases, mainly due to Rickettsia, cause considerable losses, especially in the areas between the two Niles, east of the main Nile, the Butana range, the Gash delta and around the river Atbara. Losses from infectious diseases are caused by sheep pox, pneumonia, and lamb dysentery. Sporadic mortality from anthrax occurs in some areas. Foot-and-mouth disease and bluetongue occur occasionally but they cause negligible losses. Pneumonia coccidia and Oestrus ovis cause considerable losses in sheep subjected to prolonged confinement or prolonged night bedding in one spot.
Sheep health has not been given as much importance as cattle health in the Sudan since the establishment of the Sudan Veterinary Service. This attitude might have been justified in the 1930s and 1940s. when cattle exports constituted the major animal export earnings. However, at the present time and for the foreseeable future, the earnings from sheep exports are far greater.
The vast-majority of Sudan Desert sheep exist under migratory range conditions while a few small flocks exist under a semi-residential system. The pattern of management adopted in the whole region is essentially the same. Good sheep health and extraordinary lamb crops add to the pride and prestige of devoted sheep owners. These dedicated sheepmen are aware of the importance of management to promote productivity and they strictly observe correct herding and breeding, and protection from adverse climatic conditions, disease, thieves, predatory animals and birds.
The usual size of a flock in traditional Desert sheep rangelands is 250-500 ewes. It has been realized, however, that larger flocks create herding difficulties and lessen the lambing rate. Herding is usually undertaker) by young men from the owner’s family or hired herders on a 12-month basis. The latter (who are supplied with necessary food and clothing) are charged with the care of about 10-12 weaner lambs per year, according to the size of the flock and any additional responsibilities they might be given.
The time of grazing varies between seasons. In dry seasons most of the grazing is done at night. The herders are aware of the benefit of night grazing in lessening water requirement and avoiding the stress of solar heat. They firmly believe in a local saying which states that “the ewe is like a rabbit. When it grazes at night and lies in the shade during the day, it will produce twins and triple lambs.” It has been widely recognized that exposure to high ambient temperatures reduces fertility of rams.
In the rainy season the availability of drinking-water and succulent grazing enables sheep to ingest their daily requirement in a few hours. Because of the mild temperature and frequent cloud, the sheep will continue to graze and lie down in the open air until late in the afternoon. Rainy season grazing is restricted to the period from 09.00 hours to about 16.00 hours when the plants are without dew. Diseases such as foot-rot and nematode infestation are known to result from grazing at night or early morning while the grasses are cold and damp.
Sudan Desert sheep, like other range sheep, do not tolerate prolonged confinement. Frequent shiftings of the camp and night bedding ground are always practiced for the animals’ well-being. The herder carries a few articles on his donkey, such as a bag of grain flour, a water-skin, cooking and eating utensils and a netting bag. He keeps one or more dogs to protect the sheep from predatory animals at night.
Salt is supplied in sufficient amounts for free-choice nibbling once or twice a week in winter and during the rainy season. During the hot and dry season salting is reduced to a minimum to avoid increased water requirement. Sometimes salt is dissolved in drinking-water so that each individual animal takes in an adequate amount while drinking.