Avian influenza commonly known as avian flu/bird flu affects birds throughout the world with signs ranging from mild (no deaths) to severe (90-100% birds die)
Most human cases result from close contact with sick birds with outbreaks recorded in many countries, such as U.S., parts of Asia, Europe and Africa
The severe form of the disease causes epidemics in birds and humans that spreads rapidly, devastate the poultry industry and result in severe trade restrictions
Avian influenza Animal Symptoms
Poultry are very susceptible to the disease and can die in large numbers while wild birds e.g. waterfowls can carry the disease without becoming sick
Poultry affected by avian influenza will appear depressed, have ruffled feathers and unwilling to eat.
Birds may have watery diarrhea that starts off bright green and changes to white
The combs and wattles are often swollen and can turn blue. Swelling may also occur around the eyes and neck.
Legs may have pin-point hemorrhages; Egg production drops and typically stops.
Rare cases can affect the brain causing twisted heads, circling, or paralysis. Sudden death may also occur.
Infected mammals will have fever, cough and breathing difficulty; some may die.
Avian Influenza Animal transmission
In birds, avian influenza is spread by direct contact with the fecal droppings or respiratory secretions of infected birds.
The virus can live for a long time in the environment and can be spread by objects or fomites (e.g., shoes, clothing, equipment) that have been contaminated
Mammals such as cattle, pigs, goats, sheep and humans may be exposed and infected by ingestion of infected birds
Avian InfluenzaHuman Symptoms
Clinical signs in people can include swelling and reddening of the tissues around the eyes, flu-like illness (fever, body aches). Death can occur in rare cases
Infection can also manifest as fever, cough, tiredness, muscle aches, sore throat, shortness of breath, runny nose and headache.
Pneumonia, meningitis and diarrhoea may occur. Symptoms generally appear between 2 and 10 days following contact with infected birds
Avian Influenza Human transmission
Avian Influenza infects people following close contact with infected poultry or materials contaminated with poultry feathers or feces.
Humans infected with an Avian Influenza virus rarely transmit the infection to others. Close contact with a sick person over several days may transmit.
Eating properly cooked poultry products including chicken or eggs does not result in Avian Influenza infection.
Avian Influenza Prevention
Prevent contact between poultry and wild birds, especially waterfowl.
Clean and disinfect bird housing facilities as well as rodent and insect control measures, to prevent spread of the virus.
During an outbreak consult with your veterinarian for vaccination
People in contact with Avian Influenza patients or working with infected birds, must use personal protective equipment including gloves and protective clothing.
The goal of prevention and control is to stop the virus from being severe and being transmitted between people
Ensure that poultry products are cooked thoroughly before eating. There is no evidence that avian influenza viruses can infect humans through properly cooked food.
It is recommended that poultry workers should be vaccinated with the human seasonal flu strain, to reduce the risk of virus becoming severe
When travelling to areas affected by avian influenza avoid visiting poultry farms and live bird markets to prevent spread to other regions
When travelling to areas affected by avian influenza wash your hands thoroughly after handling uncooked poultry products such as meat or eggs.
Avian Influenza Action
It is strongly recommended to vaccinate your birds against Newcastle disease, so that outbreaks of Avian Influenza can be rapidly detected.
If you suspect Avian Influenza : (1) In animals – contact your veterinarian immediately; (2) In humans – contact your physician immediately
Content provided by Zoonotic and Emerging Diseases Group (ZED) University of Liverpool, International Livestock Research Institute (ILRI), Zoonoses in Livestock in Kenya (ZooLink)
Credit: International Livestock Research Institution, ILRI
Dead Buffalo with anthrax Photo Credit ILRI/ZooLink
Anthrax Description
Anthrax is also called carbúnco or splenic fever. It used to be a global disease, but many countries have succeeded in eradicating it.
It is prevalent in East Asia, West and Central Africa, Madagascar and Central America.
Anthrax Animal Symptoms
The peracute form of Anthrax progresses rapidly! Dead animals are suspected to have died from poisoning or lightning.
As the blood does not coagulate normally with Anthrax, the blood in and around the nose, mouth, vulva and anus may be black in colour.
Symptoms of Anthrax of the acute and sub-acute form include: fever, nervousness, difficulties with breathing and walking
Symptoms of Anthrax of the acute and sub-acute form also include: convulsions (fits) and death. The blood is not always observed to be black
The chronic form of Anthrax develops slower, with a swollen tongue and bloody foam from the mouth, but the animal soon dies because it cannot breathe.
The carcass of animals that have died from Anthrax do not become rigid.
Anthrax Animal transmission
Anthrax can affect all animals, domestic and wild.
Animals become infected with Anthrax when they drink contaminated water or eat contaminated grass from a spot near where a carcass with anthrax lies exposed
Anthrax Human Symptoms
Anthrax transmitted by skin causes vesicles in the skin that are slightly painful and black colour. Without treatment, one out of five infected people die.
At the onset Anthrax via inhalation seems like a common respiratory infection, but days later it becomes more serious and may even cause death.
Symptoms of Anthrax disease from eating contaminated products are violent, expressed by vomiting and bloody diarrhoea. Some 25 to 75% of the patients die.
Anthrax Human transmission
Anthrax can be transmitted via the skin by touching the carcass, blood, wool, bones or skin of an animal that died of anthrax.
Respiratory form of Anthrax is caused by inhalation when working with leathers and wools in a closed atmosphere.
Intestinal form of Anthrax can be contracted from eating the meat or drinking the blood of an animal affected by this disease.
Anthrax Prevention
Any animal that dies suddenly is suspicious of being infected with anthrax: do not do an autopsy on this animal it can be very dangerous!
Do not do an autopsy nor touch with bare hands or eat an animal that has died of unknown causes specially if it has blood oozing out of its natural openings
Destroy the carcass as rapidly as possible by burning or burying with caustic lime. Prevent wild animals opening the carcass or grave
Beware of small skin injuries and take care of personal hygiene when disposing of a suspected dead animal. Wear gloves and protective gear
Ventilate and use proper working clothes in places where products of animal origin are handled, especially leathers and wool.
Vaccinate cattle and goats annually in regions where anthrax is common
Anthrax Action
If you suspect Anthrax: (1) In animals – contact your veterinarian; (2) In humans – contact your physician
Anthrax skin lesions Photo Credits ILRI/ZooLink
Content provided by Zoonotic and Emerging Diseases Group (ZED) University of Liverpool , International Livestock Research Institute (ILRI), Zoonoses in Livestock in Kenya (ZooLink)
Many livestock diseases can also affect farmers, Brucellosis is one of them. Diseases that can spread from livestock to humans are called zoonotic diseases
Brucellosis is a contagious disease caused by a bacteria called Brucella. It is also called undulant fever because of its remittent character.
It affects man, livestock and wild animals with a global distribution but eradicated in few countries from the animal reservoir.
Brucellosis mainly causes reproductive problems (abortions, stillbirth, infertility) in animals as well as recurring fevers, arthritis or udder infection
Symptoms in cattle are: Increased incidences of third trimester abortions, placental retention, stillbirths, infertility, arthritis and sterility in males
It is characterized by joint pain in pigs, udder infection and lameness in goats, and skin lesions in horses.
Animal Transmission
Brucellosis mainly affects sheep, goats, cattle, pigs and dogs as well as horses, camels, rodents, and wild animals such as wild pigs and water buffalo.
It is usually spread between animals thru contact with infected birth materials e.g. placenta, aborted fetuses,fetal fluids and vaginal discharges
Brucellosis can also be transmitted through contaminated objects such as, equipment, clothing, shoes, feed (e.g. hay, grass) or water.
Some animals are carriers; they will have the disease but show no signs of illness. These animals can infect other animals and people for a long period.
Some of the germs causing brucellosis are also found in semen and thus natural breeding can be a source of infection for cows for long periods or lifelong
Human symptoms
Brucellosis is usually an occupational disease; most cases occur in livestock producers, veterinarians, abattoir workers, hunters, farmers, and herders
Brucella causes undulant fever in man, which presents as febrile flu-like illness (recurring fever, night sweats, headaches, back pain) and arthritis.
Gastrointestinal signs including anorexia, nausea, vomiting, diarrhea and constipation occur frequently in adults but less often in children.
In many patients, the symptoms typically wax and wane (come and go) at 2 to 14 day intervals followed by spontaneous recovery.
Many human infections are asymptomatic (self-limiting);affecting different body parts with non-specific clinical signs that appear insidiously or abruptly
Human transmission
Humans get infected by direct or indirect contact with infected animals, their products or by-products and by inhalation of Brucella germs in the air.
People who work with animals (e.g., livestock producers, veterinarians, herders, abattoir workers, hunters) have a higher risk of infection
People are infected by consuming infected raw milk, unpasteurized dairy products (raw cheese) or undercooked meat, bone marrow or other meat products.
People can also be infected through direct contact with infected animal materials e.g abortion products like afterbirth, aborted fetuses and animal discharges
Human to human transmission is rare.
Prevention
Do not consume unpasteurized dairy products (milk, cheese, ice cream) and raw/undercooked animal products (including bone marrow and meat
Thoroughly clean and disinfect areas exposed to infected animals, their urine, blood, milk, or discharges using disinfectants e.g. hypochlorite solutions
Brucella species are readily killed by heat. Therefore boil milk and liquids for at at least 10 minutes
Separate sick animals from other animals to avoid spreading the disease
Take precautions to avoid contamination of the skin, as well as inhalation when assisting at a birth, post mortem, or butchering an animal for consumption
Good hygiene and protective clothing/equipment should always be used to avoid contamination through the skin or inhalation when handling sick animals
Particular care should be taken when handling an aborted fetus or its membranes and fluids e.g. wear gloves, wear a face mask
People who handle animal tissues (such as hunters and animal herdsman) should protect themselves by using: rubber gloves, goggles or gowns or aprons
Risky practices such as crushing the umbilical cord of newborn livestock with the teeth or skinning aborted fetuses should be avoided.
Animals from other sources should be isolated and tested before mixing or adding them to the herd.
Properly identify your animals using ear tags or branding and vaccinate all breeding animals (cattle, goats and sheep) to raise herd immunity
Vaccinate calves for Brucelosis 3-8 months of age with live vaccine for life long prevention. Vaccinate older animals yearly with dead vaccine. Use vaccine with care.
Action
There is treatment for humans. Before treatment begins, a diagnosis of brucellosis infection must be made by a doctor.
If you suspect your animals have brucellosis contact your Vet immediately!!
All zoonotic diseases are NOTIFIABLE, this means that they must be reported to the nearest Director of Veterinary Services or nearest Vet.
Information on Brucellossis can also be accessed on iCow in two parts be sending the Key Words in an SMS to 20285 (Kenya-Safaricom *285#)
Brucellosis content on iCow has been provided by the International Livestock Research Institution (ILRI) and ZED Group (Zoonotic and Emerging Diseases University of Liverpool)
It is very important that all sheep keepers keep a breeding documentation for each animal. This is the only way to prevent inbreeding. Inbreeding degrades the health and performance of all animals and ruins the effect of upgrading. The following points are very useful in preventing inbreeding:
A ram must never be allowed to mate with his sisters, daughters, grand daughters, mother or grandmother.
A ram should never serve a flock for longer than one year. He must then be exchanged.
Keep records and use one of above described systems depending on your situation. You must know at least the mother, father, grandmother and grandfather of each individual.
Ram keepers should rotate rams regularly among users and groups of sheep keepers.
Goats along with sheep, were among the earliest domesticated animals. Goat remains have been found at early archeological sites in Western Asia which suggests that the domestication of goats was originally between 6000 and 7000 BC.
The major contributor of modern goats is the Bezoar goat which is distributed from the mountains of Asia Minor across the Middle East to Sind. Unlike sheep, goats easily revert to feral or wild conditions given a chance and populations of feral goats occur in many parts of the world. The domestic goat (Capra aegagrus hircus) is closely related to the sheep as both are in the goat-antelope subfamily Caprinae. There are over three hundred distinct breeds of goat, with eight of these breeds being reared in Kenya. Goats differ from sheep in that the goat’s tail is shorter, has long hollow horns directed upwards, backward and outward, while those of the sheep are spirally twisted. The male goats (‘bucks’) have beards, unlike sheep. Male goats also have a characteristic strong odour that is produced, particularly during the rutting season. The female goat (“doe”), which has smaller horns than the male, is often called a “nanny” goat. The young are called “kids”. The male goat is called colloquially, “billy” goat. The goat’s tail is short, bare underneath and usually carried upright. Major scent glands are located around the horn base. They function in stimulating oestrus in female goats improving conception.
The goat are still used for meat and milk production. Many parts of the animal are valuable for a variety of purposes such as the hide for leather and the pelts for rugs and robes. All does that have given birth to kids should give milk but some breeds give more than others and selection processes have resulted in a number of breeds that are kept largely for milk production. In good management and feeding up to 1200 liters of milk can be achieved (average 3.5 l per lactation day). Goats can be very persistent in lactating and therefore can have extended lactations up to two years without lambing in between and continue with a relatively high yield..
Goat milk compares favourably in nutritive value with cow’s milk. It contains smaller fat globules and as a consequence is easierto digest and does not require homogenisation. It is used extensively in making cheeses. Goat milk casein and goat milk fat are more easily digested than that from cow milk. Goat milk is valued for the elderly, sick, babies, children with allergies, patients with ulcers and even preferred for raising orphan foals and puppies. In ASAL areas milk from goats and sheep still play a major role especially in child nutrition. Goat milk is higher in Vit A, Niacin, Choline and inositol than cow milk but is lower in Vit B6, B12, C and carotenoids. In about 5% of the population, cows milk causes stomach or intestinal disturbance, or occasionally facial swellings or other symptoms. This seems not to happen when such people drink goats milk
Goats which produce fibre, e.g., Angora, are generally not as suitable for meat production. This is because they are small framed and produce smaller litters than other goats. Traditionally, goats and sheep have played a major role in Kenya/East Africa through the ages. These animals have been the main source of meat and skins, contributing much to the social and economic life of people. Some communities kept milking goats, but these have mostly gone out of production, especially with the arrival of the dairy cow in the 20th century.
Milk goats are definitely the way forward for the small-holder farmer.
They not only take up less space in respect of both housing and grazing, especially if they are to be kept on zero grazing, but they eat less than a cow and will produce as much if not more milk than the average rural cow. Goats are browsers: that means that they eat leaves and branches from trees and bushes above the ground rather than eat grass on the ground.
Understand goats as the animals they are
Goats are social animals, which like to be part of a herd. They are hunted by predators, and therefore they feel safe in a herd. They have a strong hierarchy, and every goat herd has a herd queen. They have a lot of butting behavior and that is one reason for keeping horned and dehorned goats strictly apart. The kids of this goat queen will be very high ranking in the herd. The positions in the herd – especially the queen – will often be very long lasting. Goats are curious, and ‘the grass is always greener on the other side of the fence’ for goats: they are lively and explorative. Fences should always be well maintained – they will find the slightest weakness. Goats will often be biting and chewing on everything, but far from always. Goats are natural browsers and will eat leaves, shrubs, wines and twigs. They have a broad variety of things to eat, and they have a good sense of taste – they are told to be able to distinguish between sour, salt, sweet and bitter. They are well adapted to limited water intake. They are told to eat more than any other ruminant but this is not true – they spend much time on it because they move over quite some distances to get to eat what they want.
One
signal of goat wellbeing is that they keep their tail upright. If it is
‘hanging’, it is because the goat is ill or depressed for some reason.
Goats
have a strong odour, and if not properly controlled, It can be an
argument for not having male goats. Control of male goat odor (smell) is
achieved by good hygiene practices and correct housing with air, good
bedding, space and high hygiene levels. If they have sufficient choice,
they will always avoid eating plants contaminated with urine or feces
from their own species. The male goat becomes often aggressive and
dominant during the breeding season.
Apis mellifera intermissa This is a North African race of honeybee found north of the Sahara from Libya to Morocco. The bee is reputedly very aggressive and swarms frequently. During droughts over 80% of colonies may die but owing to intensive swarming colony numbers increase when conditions improve.
Apis mellifera lamarckii Egyptian bees found in North East Africa primarily in Egypt and the Sudan along the Nile Valley. Like intermissa they rear numerous queens with one colony recorded as rearing 368 queen cells and producing one small swarm with 30 queens!
Apis mellifera adansonii These bees are found in West Africa and are yellow in colour. They appear to be very similar to scutellata in many of their behaviours.
Apis mellifera capensis These bees are found in South Africa and are unique among Apis mellifera in that they have a common occurance of female-producing laying workers.Some of these races are highly aggressive if the nest is disturbed, but stay calm if there is no brood or stored honey to protect. The African bees are also more likely to abscond (abandon) their hives on slight disturbances, and in some areas the colonies migrate seasonally.
A breed is a group of domestic animals with a uniform appearance, behavior, and other characteristics that distinguish it from other animals of the same species. It is developed as a result of intensive selection of desirable traits within a large population until the selection goal has been achieved, usually after the fourth generation. Then the breed is considered to be a pure breed.
A cross bred animal results from the mating of two pure breeds of the same species. Very often this cross has qualities which are better than either of the parents. This phenomenon is called heterosis or hybrid vigour and is widely used in livestock improvement. If more improvement is desired, then “grading-up” should be done. This is a process whereby the cross bred female offspring is continually crossed with the desired male until a synthetic breed is realized.
Sheep fall into four categories: mutton, wool, dairy and dual (multi) purpose: e.g. mutton and wool, or mutton and milk. However, a majority of the current commercial breeds have been developed with specialization to one primary product in mind e.g. milk or mutton.
When selecting animals, it is important to think about the environment that they are to live in. Many pure bred animals come from Europe, where the climate is cool and good quality fodder plenty. These sheep are not usually suited for hot dry areas with little available fodder.
Hair Sheep breeds: The major hair sheep breeds include: Dorper; Nyanza Fat-tail; Persian Black Head; Red Masai and crosses of these four with local stock. The hair sheep are mainly reared in the arid and semi arid areas.
Wool and Dual purpose breeds: The major wool and dual purpose sheep breeds include: Merino; Corriedale; Hampshire Down; Romney Marsh and crosses of these breeds with local stock. The wool sheep are reared mainly in the cool high rainfall areas.
Common breeds suitable for different regions in Kenya:
Region
Sheep
High altitude
Corriedale, Merino, Hampshire Down, East African fat rumped type
Medium altitude
Dorper, East African fat rumped type, East African fat tailed type
Low altitude
Red Masai, Dorper, Persian black head
Hair sheep
a) Dorper Sheep
Dorper sheep (c) www.fergusfarm.org
Origin and distribution: The Dorper, is a composite breed of South Africa developed at The name ‘Dorper’ is a coupling of the first syllables of the parent breeds Dorset and Persian Grootfontein in 1940-50 by the Department of Agriculture and some farmers to produce maximum number of lambs with good mutton qualities, which could be marketed off arid and extensive grazing conditions. It was developed through the crossing of the Blackhead Persian ewes with the Dorset Horn rams. The name ‘Dorper’ is a coupling of the first syllables of the parent breeds Dorset and Persian. A fixed type was developed through inter-se mating. A breed society was established in 1950 in the Republic of South Africa. The Dorsian (White variety) was affiliated to Dorper in 1964. The Dorper sheep thrive in arid to semi-tropical climate and are suitable for areas with rainfall of only 100 to 760 mm. Although this breed was developed originally for the more arid areas, today they are widely spread throughout the continent.
Physical characteristics: The typical breed standard involves a short loose light covering of hair and wool (wool predominating on the forequarter) with a natural clean kemp underline. The breed is barrel-shaped, hornless (polled) with short, dull black or white hair on the head, often with black feet; they have short hair and coarse wool; the black headed ones are called “Dorper” and the white headed ones “White Dorper”.
Peculiarity: The peculiar features for the Dorper is that they were developed for arid to semi-arid environments, but are well adapted to, and perform favorably under a variety of climatic and grazing conditions, including intensive feeding systems. They are non-selective grazers and fit well in cool climates where they can be used to convert feed resources, which are not utilized or underutilized by other livestock. They have a high lambing percentage reaching up to 180% and can produce 2.25 lambs on an annual basis. Rams reach sexual maturity at an early age, rams have been observed to start working by five months.Their inherent growth potential is such that they can attain live weight of 36 kg at 3-4 months of age. They have also a very even temperament.
Utility: The breed is not only ideally suited to the purpose for which it was bred, but is adaptable to a variety of conditions throughout the world and makes a huge contribution to mutton production worldwide. It has a long breeding season which is not seasonally limited so that lambs can be dropped at any time of the year. Lambing intervals is about eight months, so under good conditions they can drop lambs three times in two years. The average litter size is 1.19 to 1.5. A lambing percentage of 150% can be reached under good conditions while, in exceptional cases, 180% can be attained. Thus on average a Doper ewe can produce 2.25 lambs on an annual basis.
Table 1 Reproduction per 100 Doper ewes mated
Variable
Number of ewes
Lambs born
Lambs weaned
Ewes mated
100
Ewes lambed
95
Ewes with single lambs
61
61
60
Ewes with twin lambs
30
60
58
Ewes with triplet lambs
4
12
10
Total number of lambs
133
128
Source: Campbell (2000)
Average birth weight was 3.48 kg for males and 3.37 kg for females.
Adult live-weight was 74 kg for males and 44 for females (DAD-IS 2005).
The Dorper lamb can reach a live-weight of about 36 kg at the age of 3-4 months.
The daily gain averages at 243 g. This ensures a high quality carcass of approximately 16 kg and is associated with the inherent growth potential of the Dorper lamb and its ability to graze at an early age.
In more marginal areas of Kenya’s Machakos District, Dorper ewes registered 10% twining rate, 78% lambing (fertility) rate, average birth weight of 3.6kg, pre-weaning lamb growth and mortality rates of 178 g/day and 14%, respectively. Average pre-weaning daily gains is 183 g/day and lamb mortality rate is 3.5% and with average weaning weights of 23.8 kg at 109 days.
Dorper ewes produce a large quantity of milk, are instinctively fond of their lambs and therefore care for, and rear, their offspring well. The Dorper ewe will nourish her lambs under difficult conditions. When the ewes are left alone they will lamb easily, and will retain and look after their lambs.A well-grown Dorper lamb has carcass qualities with respect to conformation and fat distribution, which generally qualifies for a super grading. Dressing percentages can reach 54%. In South Africa, Dorper hides are sold as top quality leather under the name “Cape glovers” and represents 20% of the total carcass value. The Dorper are not susceptible to fly strike and fleece rot. They have a high degree of disease resistance.
Dorper sheep are susceptible to gastro-intestinal nematodes (Haemonchus contortus) and have higher mortality from birth to yearling compared to Red Maasai and their crosses.
b) Red Maasai
Red Maasai sheep (c) www. abc.net.au
Origin and distribution: The Red Maasai sheep are also called Tanganyika sheep. They are sheep of the semi-arid regions of Kenya and Tanzania. Currently they are mostly found in the semi-arid regions of southern Kenyan and northern Tanzanian rangelands, especially in Kajiado District of Kenya and the neighboring districts. Before the beginning of the 20th century, their keepers the pastoral Maasai tribesmen used to occupy much wider areas, including the wetter parts of Kenya’s high and cool altitude plateaus, the upper eastern escarpments of the Great Rift Valley, such as the Kinangops, the lower slopes of the Aberdares Mountain ranges and the central highland such as, the once swampy areas of where the city of Nairobi is located.
The red Masai sheep are tolerant and/or resistant to the notorious Haemonchus contortus parasite. They are predominantly kept by the Maasai pastoralists as well as by the neighboring tribes.
Physical characteristics: The Red Maasai sheep is identified by its relatively large body size and thick red hair. However, when all of the strains are considered, the sheep are multicolored, the most preferred color by the Maasai and therefore the commonest being red, brown and occasionally pied. Average height at withers is 73 (range = 72-75) cm for males and 62 (range = 58-66) cm for females. Average heart girth and body length for females are 75.1 cm and 63.3 cm, respectively. They are short, fat-tailed and slightly fat-rumped. In populations where a fat rump is a predominant feature indicate that they may in times past have crossed with either Dorper or Black Head Somali/Persia sheep.
Peculiarity: It resists worms and other diseases. On two indicators that together provide a reasonably reliable picture of resistance – faecal egg count and packed cell volume – Red Maasai ewes and lambs performed significantly better than Dorper sheep. The associated lowered mortality rates led to much faster flock growth and productivity. The breed has also been shown to resist bluetongue virus infection and a more suited breed to survive under high trypanosome challenge.
Utility: The Red Maasai are used for their mutton and lard. Their reproductive performance in terms of lambing rate, is reported to be 80-84%, which is comparable to the Dorper sheep breed under medium rainfall zones in Kenya; the lambing interval is about 340 days, which is long compared to other East African sheep breeds, but can be improved to 246 days when crossed with the Dorper; the average litter size is about 1.13-1.21, which is lower than the Dorper and their crosses.
The average birth weight is 2.7 kg and
Average weaning weight is 15 kg with weaning rates at 97% and average daily gains at 128 gm respectively.
Mature weight for males is on average 45.5kg and 35 kg for females.
Pre-weaning daily weight gain is 105 gm for males and 98 gm for females.
The mortality (death) rates (28%) of Red Maasai sheep is better than that of Dorper sheep (66%) under moderate to high worm (Haemonchus contortus) infections.
Crosses between Dorper and Red Maasai performed 828 gm.
The scope for control of Helminthosis using treatments among the resource poor farmers is limited. That is why the Red Maasai sheep are recommended to pastoralist and smallholder farmers whose flocks experience a problem of severe haemonchosis.
c) Persian Blackhead
Black Persian sheep (c) Shi Zhao, Wikipedia
Black Persian Sheep in arid area, Isiolo (c) Monique Hunziker, Biovision
The Blackhead Persian is a fat-tailed breed of domestic sheep. The sheep is originally from Somali land. The breed is also a type of hair sheep, meaning they do not grow wool and tolerate heat better than wooled breeds and are raised primarily for mutton. The Blackhead Persian has a white body and, as their name would suggest, an entirely black head. Both sexes are polled. On average at maturity, rams weigh 68 kg and ewes 52 kg. Average birth weight is 2.6 kg. Ewes lactate for approximately 84 days; produce 50 kg of milk with 5.9% fat.
Wool sheep
a) Merino sheep
Merino sheep (c) C.Goodwin, wikipedia.org
Origin and distribution: Merino sheep were introduced into Africa in 1789 with imports of Spanish Merinos. By the mid-1800s the breed was spread over many parts of Africa. From 1891 onwards, American Vermont type Merinos were introduced. The African Merino is a composite of Spanish, Saxony, Rambouillet, American and Australian Merinos. These sheep are found mainly in semi-arid to sub-humid climates in Kenya and at medium to high altitudes under ranching and agro-pastoral management systems.
Physical characteristics: They are uni-coloured with white coat and fine-wool. They are heavy animals: males have 100 kg mature weight and females 60 kg. The average weights at birth, weaning and 18 months in female animals are 3.58 kg (range = 2.5-4.5 kg), 15.53 kg (range = 10.7-24.2 kg), and 56.2 kg (32.0-65.3 kg) respectively.
Peculiarity: The breed is adapted to high rainfall grassland regions. Animals of this breed are reported to be less susceptible to fly strike because of their smooth body in comparison to sheep with skin folds.
Utility: The Merino is mainly used for its wool; the fleece weight per year is 5.5 kg. Ewes produce an average of 7.15 kg wool ranging from 2.6-9.7 kg. The wool is medium to strong white, which is over-crimped in comparison to the Merino wool of the same strength. The wool on average measures 22-23 microns without any kemp fibres. Average staple length is 7.1 cm and ranges from 5.97-8.29 cm.
b) Corriedale
Corriedale sheep (c) Bob Nichols, wikipedia.org
Corriedale is a dual purpose breed, meaning they are used both in the production of wool and mutton. Corriedale have a long life span, and are hardy and evenly balanced all over the body. Corriedales are docile, easy care mothers, with high fertility. They adapt well to a wide range of climate conditions. They are large framed and plain bodied, polled and have a broad body. Corriedales produce a thick stapled, bulky fleece, which is popular with spinners and can be used for a range of handspun garments. Their dense fleece is medium-fine and high yielding, with good length and softness, somewhat between medium wool and long wool. Corriedale lambs produce good quality carcasses and have a high pelt value.
The Corriedale produces bulky, high-yielding wool ranging from 31.5 to 24.5 microns diameter. Fleece from a mature ewe will weigh 4.5 to 7.7 kg with a staple length of 8.9 to 15 cm. After cleaning, a yield of 50 to 60% of the raw fleece weight is common. Mature rams will weigh 79 to 125 kg, ewes can weigh from 59 to 82 kg.
c) Romney Marsh sheep
Romney Marsh sheep (c) Steven Walling, wikipedia.org
The Romney is in general an open-faced breed with long wool that grows over the legs in full.
Description:
Head wide, level between ears, with no horns or dark hair on the poll. Eyes are large, bright and prominent and the mouth sound. Face in ewes full, and in rams broad and masculine in appearance. Nose and hooves are black. Neck well set in at the shoulders, strong and not too long. Shoulders well put in and level with the back. Chest is wide and deep; back straight and long, with a wide and deep loin; Rump wide, long and well-turned. Tail set almost even with the chine. Thighs well let down and developed. The face is white, and the skin is of pink pigmentation. Ribs are well sprung; legs well set, with good bone and sound feet. Sheep stand well on their pasterns. The fleece is of white colour, even texture and a good decided staple from top of head to end of tail and free from kemp.
Fleece characteristics
Romneys produce a heavy fleece. A healthy mature ram can yield at shearing upwards of 10 kg per year, while flock averages for breeding ewes are typically above 5 kg. The increased fleece weight of a long-wooled sheep comes from the longer fiber length produced. The “clean yield” (net weight after thorough washing) is typically high for Romneys, 75-80%; this is a higher yield than is got for most fine-wooled sheep.
Sheep are foragers and can walk over quite large distance to graze. They are not climbers like goats. Housing in tropical and semi-tropical regions can therefore be kept to a minimum, as a night shelter or a shelter in extreme weather conditions like excessive rain in humid areas, to protect the animals and especially the young ones. It can be relevant in cases of serious predator problems. In the arid tropics no protection other than natural shade is required. Sheep do not tolerate mud well; therefore yards and shelters should be built only on well drained ground.
Where housing facilities are provided, it will be necessary to provide water and feed troughs. A feed trough should be 0.3 to 0.4m deep front to back and have a 0.5 to 0.6m high front wall facing the feed alley
In temperate climates and at high altitudes it can be necessary with a more substantial structure may be needed. FAO recommends to build an open-front building facing north provides wind protection and a maximum of sunshine. A rammed earth floor with a slope of 1:50 toward the open front is recommended. A concrete apron sloped 1:25 and extending from 1.2m inside to 2.4 m outside will help maintain clean conditions in the barn.
It can be practical to organise the housing facilities in a way so that temporary panels can be placed to help divide and handle the flock when necessary, e.g. in case of disease handling or lambing. Individual lambing pens should be 1.5m depending on the weight of the ewe and number of lambs expected.
In areas of high rainfall it may be desirable to keep the animals off the ground. Stilted houses with a slatted floor which is raised 1 to 1.5m above the ground to facilitate cleaning and the collection of dung and urine can be very practical in such area. If making a slatted floor, slats shall be 70 to 100 mm wide – remember that sheep have small claws, and that they are walkers and not climbers, so they feel uncertain on a high floor with slats. The slats should be 25 to 30 mm thick and laid with 25 mm spaces.
Milking can be facilitated by providing a platform along the feeding fence where the animals can stand while being milked from behind. Such a platform should be 0.8m deep and elevated 0.35 to 0.5m above the floor where the milker stands.
Traditional sheep husbandry systems are ecologically well-balanced, but often the food available to sheep is fibrous and deficient in energy and protein and minerals are in short supply. Nutrition plays a major role in the overall productivity, health, and well-being of the sheep flock. Because feed costs account for approximately two-thirds of the total cost of production, it is important that producers consider nutrition management a top priority. The sheep owner should try to balance the demands of the sheep breed and the quality (and quantity) ot the feed. It makes no sense to breed a very energy rich ration demanding sheep breed when it is impossible to meet that in the management. Nutrient requirements of sheep vary with differences in age, body weight, and stage of production. The five major categories of nutrients required by sheep are:
During the grazing season, sheep are able to meet their nutrient requirements from pasture and a salt and mineral supplement. Pastures of mixed grass and clover, alfalfa and small grain serve as excellent sources of nutrition for growing lambs. A source of clean, fresh water should be provided to sheep at all times.Ewe body weight does not remain constant throughout the year, but changes with stage of production. Nutrient requirements are lowest for ewes during maintenance, increase gradually from early to late gestation, and are highest during lactation. Decisions affecting feeding management are improved significantly by knowing ewe body weight and condition score at three distinct stages of production:
1) Three weeks before breeding; 2) Mid-gestation; and 3) Weaning.
Condition score to measure body fat
Condition score is a subjective measure of body fat that is most easily determined by handling ewes down their back. It is the best method available to monitor nutritional status and overall well-being of the sheep flock. Condition scores range from 0 to 5, with 0 being extremely thin and 5 being very fat. Condition scores at either end of the scale are undesirable. Ideally, ewes should range from a condition score of 2.5 at weaning to a 3.5 at lambing. When necessary, thin ewes are separated and fed additional energy to increase body condition. Conversely, obese ewes are separated and fed a lower energy diet at a stage of production when body weight loss is acceptable. It should be noted that problems with over fat ewes are far fewer than those associated with ewes that are too thin.
Body condition score 0 – extremely thin
Backbone: The bones form a Sharp narrow ridge. Each vertebra can be easily felt as a bone under the skin. There is only a very small eye muscle. The sheep is emaciated and you have a serious animal welfare problem
Short Ribs: The ends of the short ribs are very obvious. It is easy to feel the squarish shape of the ends. Using fingers spread 1 cm apart, it feels like the fingernail under the skin with practically no covering
Diagram showing a body condition score 0 – extremely thin (c) Andrew Marete, 2011
Body condition score 5 – very fat
Backbone: The spine may only be felt (if at all) by pressing down firmly between the fat covered eye muscles. A bustle of fat may appear over the tail. This sheep is seriously overweight and the diet needs to be modified.
Short Ribs: It is virtually impossible to feel under the ends as the triangle formed by the long ribs and hip bone is filled with meat and fat. The short rib ends cannot be felt.
Diagram showing a body condition score 5 – very fat (c) Andrew Marete, 2011
Starting two weeks before breeding and continuing two weeks into the breeding period, ewes should be placed on high-quality pasture or supplemented daily with 0.5 to 1 Kg whole shelled maize or barley. This management practice is called flushing and has been shown to improve lambing percentage by 10 to 20 percent. Flushing works best with mature ewes that are in moderate body condition, and has been shown to be more effective for early- and out-of-season breeding than at the seasonal peak of ovulation. Most prenatal deaths occur within the first 25 days after breeding and are usually associated with poor nutrition. Therefore, it is important not to make dramatic reductions in nutrient supplies during the breeding season. Pastures with more than 50 percent legumes should be avoided during breeding because legumes may contain compounds that reduce conception rates.From breeding to six weeks before lambing, the ewe flock can be maintained on permanent pastures, small grain pastures, stockpiled fescue, aftermath crop fields, or hay. Fetal growth is minimal, and the total feed requirement of the ewe is not significantly different from a maintenance diet. (See table 1) The developing fetus reach approximately two-thirds of its weight during the last six weeks of pregnancy. Rumen capacity may be limited with ewes carrying multiple fetuses. Therefore, it is important to supplement ewes with 0.5 to 1 kg of maize/energy rich feed, in addition to their normal diet starting six weeks before lambing, to prevent pregnancy toxemia, low birth weights, weak lambs at birth, and low milk production. Producers should be careful not to over feed grain during late gestation, which could result in lambing difficulty caused by large lambs.
Table 1. Daily requirements of ewes with body weight of 50 and 70 kg in different stages of production for energy and protein, calcium and phosphorus and for vitamin A and E and the maximum dry matter intake capacity (DMI) of the ewes.
Live-weight
Category
DailyGain (g)
DMI
MEM/cal
CrudeProtein(g)
Calciumg
Phosphorusg
Vit AIU
Vit EIU
50
Maintenance
10
1.0
2
95
2.0
1.8
2350
15
Flushing breeding
100
1.6
3.4
150
5.3
2.3.6
2350
24
Gestation:15 weeks
30
1.2
2.4
112
2.9
2.1
2350
18
Last 4 weeks gestation 140% lambing/last 4-6 weeks suckling singles
18045
1.6
3.4
175
5.9
4.8
4250
24
Last 4 weeks gestation 200% lambing
225
1.7
4.0
196
6.2
3.4
4250
26
First 6-8 weeks suclingsingles/Last 4-6 weeks suckling twins
-2590
2.1
4.9
304
8.9
6.1
4250
32
70
Maintenance
1.2
2.4
113
2.5
2.4
3290
18
Flushing breeding
100
1.8
3.8
164
5.7
3.2
3290
27
Gestation: 15 weeks
30
1.4
2.8
130
3.8
3.3
3290
21
Last 4 weeks gestation 140% lambing/last 4-6 weeks suckling singles
18045
1.8
3.8
193
6.2
5.6
5950
27
Last 4 weeks gestation 200% lambing
225
1.9
4.4
214
7.6
4.5
5950
28
First 6-8 weeks suckling singles/Last 4-6 weeks suckling twins
-2590
2.5
5.9
334
9.3
7
5950
38
After lambing, the energy and protein requirements of the ewe increase by 30 and 55 percent, respectively. Failure to supplement ewes accordingly results in excessive body weight loss, low milk production and poor lamb gains. Protein supplementation is especially critical for ewe flocks with a high percentage of multiple births. Unless high quality legume hays are fed, protein supplementation will be necessary as a part of the grain portion of the diet. A general rule of thumb for concentrate feeding of lactating ewes is 0.5 Kg of grain for each ewe nursing the lamb. Ewes should be sorted into feeding groups based on type of rearing (single, twin, etc.) to make sure grain supplements are neither over- or underfed.
Urea
Urea is not normally used in organic herds, and if used, very careful measuring needs to take place as urea used badly can kill your animals very fast. Do not try urea unless there are goof facilities for weighing and mixing feeds properly. Urea is not a protein supplement, but a source of non-protein nitrogen (NPN) for protein synthesis by rumen bacteria. It should be used only in conjunction with high-energy feeds such as maize. Urea, which is 45 percent nitrogen and has a crude protein equivalent of 281 percent, should not supply over one-third of the total nitrogen in a diet. To determine the grams of nitrogen in a diet, multiply the total kilos of crude protein in the diet by 16 percent. Other general rules for the use of urea are:
1) Should not be more than 1 percent of the diet or 3 percent of the concentrate mix; and
2) Should not be more than 5 percent of a supplement to be used with low grade roughages.
Minerals
Salt and mineral supplementation is required on a free choice, year-round basis. Failure to supplement salt and minerals results in low fertility, weak lambs at birth, lowered milk production, impaired immunity, and numerous metabolic disorders. A variety of salt and mineral supplements specifically formulated for sheep are commercially available. These supplements range from trace mineralized salt (TMS) fortified with selenium to complete mineral mixes containing all of the macro and micro minerals required by sheep.
Vitamins
Pasture or high-quality hay provides the vitamins required by most categories of sheep. However, after a drought, or when low-quality hay or silage is fed, a supplement supplying vitamins A, D, and E may be needed.
Table 2, Average daily mineral and trace element requirements for different categories of sheep
Category
kg DM
Ca
P
Mg
Na
K
Cl
S
Cu
Co
Mo
J
Zn
Mn
Fe
Se
g
g
g
g
g
g
g
mg
mg
mg
mg
mg
mg
mg
mg
Gestation
1.9
5.6
3.7
1.7
0.7
4.9
1.1
2.85
14
0.2
0.19
1.5
30
38
92
0.18
2 kg milk
2.3
8.3
7
3.8
1.9
11
3.8
3.3
15
0.26
0.23
1.5
56
46
19
0.32
3 kg milk
2.6
10
9.2
4.4
2.4
13
4.8
3.9
18
0.3
0.26
1.5
66
52
23
0.37
Weaning lambs
The ability to supply adequate grass for lambs is the key to successful weaning. Lambs are selective grazers, selecting the sweetest and best grass for themselves. Do not allow ewes to compete with lambs for grass from 14 weeks onwards.
Ensure lambs are in a well fenced field with an abundance of leafy grass. Sward (grass) heights should be maintained at 8-9cm. Move lambs to the best grass on the farm, ideally after-grass containing clover.
Do not graze tightly. Use a follower group of stock to clean up.
During rains and up to weaning lambs may gain 300g per day. After weaning they can only gain 100-200gm per day, depending on grass quality and availability.
Consider using a pour-on for fly strike as they have a shorter withdrawal period than dips. Do not dip if you expect to sell within the next month; Clip around the tail to keep clean. (antibiotic withdraw time double in organic)
A stomach worm dose for lambs at weaning is advisable, especially when moving to after-grass. It is not necessary if a drench was used in the last few weeks.
Treat for cobalt in deficient areas. Lambs suffering from cobalt deficiency (pining) will lose condition and wool will dry out. The main method of supplementation is orally – it can be mixed with drinking water, as cobalt by injection is not as effective. Dosing every 2 weeks with cobalt sulphate is recommended in deficiency situations.
Restrict ewe feed for 1-2 weeks to stop milk production when weaning lambs early. This can be on a bare paddock or indoors. Do not restrict too severely, as this could leave ewes too low in condition before going to the ram. Be careful if keeping ewes indoors for a few days after weaning to ensure that they are well bedded, otherwise an outbreak of mastitis is possible.
Select potential replacement ewe lambs post-weaning, in cold season when only the poor performing ewe lambs are left it is too late.
Where grass becomes scarce, introduce meal and continue meal feeding until lambs is sold. Concentrate supplementation of weaned lambs on pasture increases carcass weight and leads to earlier drafting of lambs. Response to meal feeding post-weaning is 10-12 kg/kg carcass wt. With meal at PS130/tonne and lambs at Ksh.350/kg this means that Ksh.200 spent on meal will give a return of Ksh.350.
Table 3. Daily requirements of lams with adult body weight of 50 and 70 kg for energy and protein, calcium and phosphorus and for vitamin A and E and the maximum dry matter intake capacity (DMI) of the ewes.
Sheep respond very well to good care and management, so the first step to improve their health is to provide good feeding and control diseases and parasites. Only then can further improvements be made by implementing a good breeding program.
Selection methods:
There are basically 3 ways of selecting individuals, and these can be combined
Individual selection – on the basis of their own performance irrespective of family (or mass selection). Comparing individuals on the basis of their own performance is often called a performance test. In most situations individual selection is the best procedure as it takes account of all the additive genetic variation that is present in the population.
Family selection – by choosing the best families as a whole and rejecting others (also called between family selection). Here selection is on the average value for the family and takes no separate accounts of individuals. Family selection may increase the rate of inbreeding so is not recommended for common use.
Within family selection – choosing the best individuals from each family. This procedure retains at least one representative from each family for the next generation. It is most useful when differences between families are mostly due to environmental factors. Retaining at least one member from each family for the future can also be helpful in reducing problems of inbreeding.
Breeding Methodologies
Also in sheep breeding should be considered what sheep breed or crossing fits best to the circumstances at the farm. Local breeds in general are more hardy and disease resistant and used to the climate conditions, exotic breeds have higher growth rate but need better conditions (better feed quality) than the local breeds. If that can’t be offered, exotic breeds will not produce more and will need more (medical) care than the indigenous breeds. Crosses between local and exotic breeds could be a possibility to keep disease level low and collect the good genes from both breeds in the offspring. Collaborating as sheep owners in exchanging breeding rams can lead to a quick improvement the sheep flocks on individual farms.
See also in Integrating animals into the farm – what to consider when choosing to keep animals.
Grading up
Ewes from local breeds and their female offspring are mated with rams of a more productive breed for example Dorper rams. The resulting crosses are then mated with non-related animals with the same level of cross breeding (first generation 50%, second generation 25% or 75% depending on ram used). Positive traits of the local breed (disease, parasite and drought resistance can be maintained this way. Maasai-Dorper crosses for example are most productive with 75% Red Maasai blood.
Crossbreeding
Crossbreeding refers to the crossing or mating of two pure breeds, but the term is frequently extended to include the offspring of purebred sires and crossbred females. When two purebreds are used, characteristics of the first cross animal should show:
1. Outstanding individual merit
2. Intermediate expressions between the parent types and
3. Resemblance to one or other of the parent types.
Crossbreeding of sheep is widely practiced throughout EA, especially between indigenous Red Maasai sheep and Dorper and Dorset Horn for improved performance. It should be the objective of the breeder to produce offspring superior to both parents. This is achieved when the progeny resulting from crosses demonstrate extra or improved performance above the average of the parents (heterosis or hybrid vigor).
There is no doubt that crossbreeding is an important method of commercial sheep production. The vigour, thrift and general excellence of the first cross sheep are features that are especially apparent and which can be measured accurately in terms of increased returns. As sheep production becomes more intensive for both mutton and milk production, it is likely that cross breeding and exploitation of hybrid vigour will become more popular.
Group breeding scheme without nucleus by use of reference rams
One of the main benefits from cooperation among breeders is that the animal population directly involved in a selection program is enlarged compared to what is available to the individual breeder. In order to know whether a ram used in one flock is genetically better than one of the rams in the other cooperating flocks, it is necessary to have some sort of link between the flocks. This can be done by identifying so called reference rams. These rams leave offspring in several or possibly all cooperating flocks, The offspring of the reference rams can then be compared with offspring of any other ram used in the same flock. This way the best rams in the whole of the group breeding scheme:
Can be identified, with the help of appropriate statistical tools
Can become available to the scheme as a whole
Can be used to breed the next generation of males
If a community wants to upgrade and improve the quality of their herds it is recommended to seek advice from professional breeders to set up breeding schemes that fit the objectives in hand.
Nucleus group breeding schemes
These breeding methods were pioneered in New Zeeland and Australia , but successfully adopted in many countries. For such a scheme a number of flock(or herd) owners agree to cooperate by deciding on common breeding aims and pooling their animal resources. The key of such a scheme is to create a nucleus – or central flock from the best of the breeding females of each participating flock. Very good record keeping is necessary.
The nucleus flock in this case was set up from the best females from the participating flocks. Thereafter each year the poorest females (40 in this example) are culled from the nucleus flock and replaced by an equivalent number from the cooperating flocks, taking the best (8 females) from each. The best of the rams are used in the nucleus flock and the next best in the cooperating flocks.
Open Nucleus breeding scheme – an example of a group breeding scheme with sheep (c) Gerals Wiener 1994 Animal breeding – The Tropical Agriculturalist. Macmillan Publishers
Sheep reproductive traits
Ewes
Mature weight
90 – 300 lb.
Breeding season
early February to late June (some are poly-estrous year around, ex. Dorset)
Estrous cycle
14 – 19 days seasonally poly-estrous
Duration of estrus
24 – 36 hr. (standing heat)
Time of ovulation
24 – 30 hr. from beginning of estrus
Gestation period
145 -155 days
Breeding/year
1 – 2/yr.
Artificial Insemination
Yes Cervical or Vaginal Method Intrauterine Method (not available in Kenya)
