Indigenous chicken farming has been described variously as backyard poultry rearing, rural poultry production or scavenging. For our purpose, any flock of chicken that is kept under free-range management and on which no selection of breeds or improvement by crossbreeding has been done is considered as a flock of indigenous chickens. Indigenous chicken lay between 8 and 15 eggs per clutch depending on availability of feed. They are broody and hatch about 80% of the eggs they sit on. They attain 2-3 clutches in a year.
The few chicks that attain 20-30% maturity form most of the replacement stock. These birds, though under poor management, live within the families for many years. They form an important part of family life playing important cultural roles besides being a valuable source of protein and income.
Indigenous chickens have not attained their full production potential due to exposure to risks that militate against their survival and productivity. Constraints to production include diseases, predators and poor nutrition. Indigenous chicken can be profitable if managed well. Control of common diseases in the free-range system could improve the survival rate of chicks by at least 30% while improved feeding, housing and disease control could increase the survival rate to 80%.
Families could improve their income and supply of poultry products (meat and eggs) by practising a combination of recommendations given in this manual. The aim of this manual is to create awareness and interest in indigenous chicken production. The reader is encouraged to consult the Ministry of Livestock and Fisheries Development and the Kenya Agricultural Research Institute (KARI) for further information.
Birds need feeds that give the necessary elements for body functions, including growth, and egg and meat production. This is a requirement that the free-range production system does not meet adequately. To attain a balanced diet, it is recommended that in addition to scavenging, a farmer should include protein supplements from one of the recommended cheap but quality sources. This can be provided either as a pre-mix or given through the cafeteria system.
Animals need carbohydrates for the supply of energy and heat. In addition to kitchen waste, birds should be given feed rich in energy such as maize, millet, cassava, sweet potatoes and sorghum.
Proteins are bodybuilding blocks that are essential for growth and production. Feed birds on protein-rich non-conventional feed such as yeast, ‘Busaa’ waste (dregs [Machicha]), sunflower cake, heat-treated soya or ordinary beans, lucerne, peas, lupins, fishmeal (Omena), dried blood, rumen content, earthworms and termites. Termites are trapped by slightly watering leafy waste such as maize stover and rubbish collected from the compound and leaving them outside for 2 or 3 days.
Minerals are trace elements found in plant seeds and grates. Minerals such as calcium that are important for bone and eggshell formation are found in fishmeal.
Vitamins are necessary for growth and reproduction. The rich, yellow pigment in the skin and egg yolk of indigenous chicken indicates presence of carotenoids from fresh vegetation such as grass and vegetables, the precursors of vitamin A.
Water is often not provided because farmers assume that the birds find it around the homestead. Birds drink water from ponds and open tins during the rains but it is better to give them clean and fresh water all the time at a specific place (Fig. 1). It is easy to medicate birds that drink from a central place.
Protective housing should be used in a free-range poultry farming system to protect chicks from predators and bad weather. Several housing structures including the dome-shaped stick basket popular in western Kenya variably known as Lisera, Liuli or Osero (Fig. 2) which is ideal for daytime housing are found. Other alternatives include the stick-built Kiduli and standard poultry houses Fig. 3). A good housing structure should be spacious, well lit, airy and dry, easy to clean, have perches for chickens to roost and protected from predators.
Cleaning and disinfecting
A chicken house should be decontaminated using fumes (fumigation) produced from chemicals such as potassium permanganate and formalin to kill germs. The house must be tightly sealed so that the fumes remain in circulation for 18-24 h. These conditions are not possible for indigenous poultry houses. Contamination should be avoided by restricting entry into the house, quarantining all new chickens by separating them from the flock,
keeping the house clean and wiping all surfaces with one part of jik in 3 parts of water. Keep non-concrete floors smooth by smearing regularly with cow dung and dusting with pesticides such as Sevin or Actelic to keep away vermin.
Fig. 1. Give clean and fresh water in a specific place
Fig. 2. (left) Protective housing shields chicks from predators and harsh weather. (Fig. 3) (right) Simple houses built with sticks, mud and polythene paper are easy and cheaper to construct
Avoid inbreeding by introducing one cock for every 10 hens every 2 years.
Selection of eggs for setting
Improved nutrition can raise the average number of eggs laid per clutch by 100%. Fertilised eggs are live and successful hatching depends on how they are taken care of from laying till setting. The broad end of an egg has an air sac through which the egg breathes. Eggs should be stored with the broad end facing upwards. The egg shell is porous (has little holes which if blocked may suffocate the embryo [baby chick]). To prevent rotting, eggs must be stored in a clean and dry place. Since fertile eggs grow slowly, eggs that are more than 14 days old should not be used for hatching.
Shortening the reproductive cycle
Table 1 compares normal and shortened reproductive cycles.
Hens lay eggs earlier, doubling the number of clutches per hen per year while the improved management increases survival rates from 2-6.
Table 1. Normal and shortened reproductive cycles
|15-20 days||21 days||60||0 days||101 days|
|15 eggs||8 chicks||2 growers|
|15-20 days||21 days||0 days||61 days|
|15 eggs||10 eggs||8 chicks||6 growers|
Hens or ducks can be used to sit on eggs continuously for 2 or more times by removing chicks every time they hatch and replacing them with new eggs. If this is coupled with synchronisation, then a farmer could hatch more chicks without using an incubator. Ducks can sit on 30-35 eggs and can be used for up to 6 consecutive times.
When hens that started laying within the same week reach broodiness, the 1st hen to reach this stage can be delayed by being given one egg to sit on. This can be repeated for the 2nd and 3rd hens so that finally all the hens are set on one day.
On the day of setting, all the dummy eggs should be destroyed. Chicks that hatch on the same day fit in well with feeding and vaccination programmes. The time between the 1st hen and the last should not be more than one week.
Fig. 4. Synchronised ducks sitting on eggs
Management of chicks – brooding
At this delicate age, chicks need very careful care in order to grow properly. Farmers have been known to lose many chicks due to poor brooding. A successful brooding translates to more profits.
What is brooding?
Brooding is the art and science of rearing chicks from day-old to four weeks.
How to reduce chick Mortality during brooding
It is important to know the reasons for early chicks’ mortality as they can be prevented. These may include;
- Poor brooding conditions-High and low brooding temperatures
- Feed poisoning-fungal, toxins, litter poisoning (ingestion of sawdust)
- Injuries-rough handling and pro-longed transportation stress
- Nutrition deficiency
- Genetic disorder
Prerequisites to brooding
- Isolation of brooding houses from other older bird houses All an all-out
program is recommended
- All facilities must thoroughly be cleaned & disinfected
- Before the arrival of the chicks the brooder ring and the heaters must
be checked to ensure that they are working properly
- On arrival, chicks should be offered fresh water containing glucose where
To prevent high mortality, chicks must be kept in a safe, warm and clean environment and must have easy-to-digest feed at all times. Chicks may be removed from the hatching hen or duck and kept separate using the following brooding methods:
2. They cannot maintain their body temperature and are subject to chilling
3. Brooding is aimed at providing the correct temperature for the growing chick
When heat is not provided from external sources, the chicks will not takeChicks have not developed mechanisms to regulate their
body temperature when hatched
sufficient feeds and water
2. This leads to retardation of growth and poor development of internal organs, responsible for digestion
3. Thus the chicks will not be able to digest the yolk completely
4. Egg yolk is highly nutritious feed for the chicks When the yolk is not absorbed completely by the chicks, there is growth and multiplication of bacteria on the yolk leading to Early Chicks Mortality [ECM] and growth retardation. This condition is termed as omphalitis [yolk infection]
Box or Carton
In a carton box with ventilation holes drilled around the upper side with
wood shavings as bedding and warmed by either a lantern or by covering the
top with a blanket or a clean sisal sack at night.
In ‘Liuli’ on a sisal sack or wood shavings and warmed as above.
Do not use a lantern under the basket. The basket or Liuli can be taken out
when the sun shines. However, the birds should be protected from very hot
sun and rain.
Hens that do not discriminate against chicks can be trained as foster hens.
Up to 65 chicks of different ages can be brooded by such a hen (Fig. 5).
When it gets cold, the youngest chicks are the 1st to go under the hen and
the oldest will come later around the hen.
2. Haybox brooder
A hay box brooder is easy to make and is basically a wooden truck with a
top that can be opened or closed. The box is insulated from inside [along
the sides] by hay, demarcated by chick wire mesh creating a central warm
area where the chicks will sleep
• This is only an overnight box and chicks are taken out during the day.
Feed and water are kept out. Provide shelter and make sure the chicks are
not exposed to bad weather during the day
Sources of Heating
• Domestic heaters [jiko] 1 for 100 chicks
• Infrared lamps [250 watts ] 1 for 250 chicks
• Pancake heaters 1 for 1000 chicks
The ideal brooding temperature are as measured at the edge of the hover and
5cm above the litter surface
1. Evening is the best time to observe the chicks and make temperature adjustments
2. Thermometers may not always be available
3. Therefore, use the behaviour of the chicks as the guide
4. Relative humidity, light and ventilation should be provided for
5. optimal comfort of the chicks
Continuous lighting should be provided for the first 48-72 hours
2. The light intensity should be enough to read a newspaper
3. Recommended Daily hours of lighting
|Age in days||Hours of lighting|
s 1-3 4-7 8-14 15-21 22-28
Hours of lighting 23 22 20 19 18
1. The feed trough or pan height should be adjusted so that they rest on
the litter for the first 14 days to ensure all the birds can easily access
feed without having to climb into the feeder
2. Therefore, feeders should be raised incrementally throughout the growing
period so that the lip of the trough or pan is level with the birds’ back
at all times.
3. Adequate floor,feeder and drinking spaces are also important
4. Free moving spaces should be provided all around the feeders and the
drinkers,so that the chicks can feed and drink freely
Chick Feeding trays
1. The use of supplemental feeder trays at placement is recommended to help
chicks get off to the best
2. Trays should be provided at the rate of 1 per 100 chicks and should be
placed between the main feed and drinker lines and adjacent to the brooders
3. Supplemental feeders should be provided for the first 7-10 days
1. Use an 18 mm cardboard sheet, aluminium sheet, or coffee wire as brooder
guard material to make a circle that uses
1. 20 feet for 50 chicks
2. 25 feet for 100 chicks
3. 30 feet for 150 chicks
4. 35 feet for 200 chicks
2. The brooder should be ready prior to fumigation
3. Fill the ring with litter material such as wood shaving, straw etc up to
4 inches thick from the floor
4. Place the heat source at the centre of the brooder
Induction of the chicks
1. Light the brooder heat source an hour prior to chick arrival so that the
ring temperature is 32-340C
2. Count the chicks proper while receiving
3. Release the chicks into the brooder ring after dipping their beaks in
4. Wait for some time to allow the chicks to drink water and keep feed in a
chick feeding tray or clean egg
Temperature Step down
Diseases may be defined as illness of one or more of the body organs or tissues, caused by pathogens or germs. Germs (virus, bacteria) and protozoa are classified according to size. Parasites, though not germs, can cause ill health. The significance of a disease depends on the rate of infection or infestation and the number of birds that die. Death rates depend on age and nutritional status.
Protozoa such as Emiria tenella (coccidia) are larger than bacteria hence more easily visible by microscope. Outbreaks of protozoan diseases are an indication of poor sanitation and hygiene.
Prevention and control
Vaccination and isolation of healthy birds from sick ones and proper disposal of dead birds can prevent diseases.
Vaccination is the use of mild, live or inactivated infective agent (virus or bacteria) to stimulate production of antibodies to a specific infective agent. Antibodies are chemical substances produced within the host body. They recognise and destroy the virus or bacteria used during vaccination before onset of disease. Vaccines are prepared from the same virus or bacteria that cause the disease to be vaccinated against. They are sensitive to heat, pH (acidity) and therefore should be handled following manufacturers’ instructions.
Vaccination for indigenous chicken in a free-range system depends on age, disease incidence, severity and status of endemic diseases (Table 2).
Table 2. Disease occurrence and recommended treatment
|Disease||Species affected||Age affected||Symptoms||Treatment|
|NCD||Chicken, turkeys &||All||Depression, poor appetite, cough- ing and difficult breathing, diar||Vaccination
|domestic||rhoea, nervous signs, twisted neck||control sec-|
|birds||and death in large numbers in a||ondary infec-|
|Fowl||Chicken||All but||Spreading eruption on comb, wat-|
|pox||and tur-||serious||tle nose & other featherless parts,|
|keys||at point||poor appetite/egg production, de-|
|of lay||pression. Deaths may result in|
|Infec- tious||Chicken||All||Chicks/growers: Depression, hud- dling, poor appetite, coughing,||”|
|Bronchi-||gasping/difficult breathing, death.|
|tis||Adult: Coughing/noisy breathing,|
|few eggs laid/with soft shells|
|Chicken and tur-||All||Depression, coughing, discharge from eyes/nostrils, swollen face,||Destroy sick birds|
|keys||poor sight and feeding, nervous|
|signs and diarrhoea|
|IBD||Chicken||2-6 wk||Depression, poor appetite, un-
steady walk, pecking at vent and
|Control by vaccination|
Bacteria are minute germs that can only be seen under microscopes. They cause diseases that can be prevented through good hygiene and treated using antibiotics such as Tetracycline.
Salmonella. There are 3 types of infection caused by the Salmonella microorganism. These are pullorum disease, fowl typhoid disease and salmonellosis.
Pullorum disease caused by sub-species S. pullorum is fatal in chicks. It is transmitted from hen to chicks during egg formation, contamination of eggs at laying or the chicks are infected from faeces. Symptoms include dead embryo in eggs that do not hatch, chicks develop wet vents (tail) within the 1st week, whitish diarrhoea, huddling and difficulty in breathing. Mortality can reach 100% in the 1st 2 weeks.
Fowl typhoid is caused by the species S. gallinarum and is severe in growers and adult birds. It is spread by contamination of feed and water by faecal matter from infected birds. Symptoms include drop in egg production, egg fertility and hatchability, anorexia and dullness followed by sudden death.
Salmonellosis is caused by any other Salmonella species. It is severe in both chicks and adult birds. It is spread by contamination of eggs at laying or to both chicks and adults through contaminated feed, water and faeces. Symptoms include drop in egg production, egg fertility and hatchability, anorexia and dullness followed by sudden death.
Sanitation, and eggs and nest fumigation using formaldehyde pellets in the nest can prevent it. Broad-spectrum antibiotics such as sulphur drugs can control infections. Control is by vaccination (Table 3).
Collibacillosis is acute in chicks and chronic in adult chicken. It is transmitted through eggs to chicks and through contaminated faeces, feed and water to both adult birds and chicks. Symptoms include respiratory distress, diarrhoea and high mortality in chicks while those in embryonic infection include dead embryos in spoiled eggs. It can be avoided by maintaining standard egg sanitation and using broad-spectrum antibiotics such as sulphur and tetracycline to treat and to reduce transmission. It can be controlled by vaccinating with bacterin.
Infectious Coryza can be acute, mild or chronic. It is spread by faecal matter, aerosols or through contaminated feed and water. Symptoms include swollen watery eyes, nasal discharge, laboured breathing and drop in egg production. It can be prevented by vaccinating with bacterin in water at 10-12 weeks and 16-18 weeks. All clinically ill birds should be destroyed.
Table 3. Disease occurrence and recommended treatment
|Disease||Type||Cause||symptoms||Prevention and treatment|
|Chiggers, red bugs|
|Air Sac Disease|
|Ascarids (Large Intestinal Roundworms)|
|Avian Pox||Fowl pox can come in two forms, wet or dry.|
• unfeathered areas have wart-like lesions that heal in about two weeks.
• lesions around the mouth
• discharge from your eyes.
|Fowl Pox||skin||Fowlpox can come in two forms, wet or dry.|
• unfeathered areas have wart-like lesions that heal in about two weeks.
• lesions around the mouth
• discharge from your eyes.
|Provide footbath with disinfectantLimit visitors to the unit
Workers should move from young to old flock in the units.
Clean and disinfect the house and equipment at the end of each crop and rest it for
1 to 2 weeks
There is no treatment for fowl pox, but it will typically go away after a few weeks on its own. We suggest giving any sick chickens a little extra care to make sure theyre as comfortable as possible
|Bowlegs in Chicken|
|Crazy chick||• chicks unable to walk in a straight line.|
• chick may suddenly shake, topple and fall on their sides
• putting their heads between their legs.
• chicks alert. appetite not affected.
|Fowl Cholera||Blood stream||pasteurella avicida||• Dejection.|
• Ruffled feathers.
• Loss of appetite.
• Nasal, ocular and oral discharge.
• Swollen and cyanotic wattles and face.
• Sudden death.
• Swollen joints.
|Birds with acute type should be destroyed and burned. House should be thoroughly cleaned and disinfected. Treatment with recommended sulphur drugs is effective. Ensuring there is no wet litter is important, which provides ideal conditions for coccidian.|
|Fowl Typhoid||Blood||salomonella gallinarum or shigella gallinarum||• ruffled feathers|
• pale head
• drooping comb
• orange coloured diarrhoea
Fowl Tick (Blue Bug)
|Vaccinate the birds at 7 weeks of age. Destroy all dead birds by burning.Do not allow visitors to enter into the poultry unit without being disinfected|
|gape worms||• open-mouth breathing|
• grunting sound
• difficulty breathing
|Gapes||These are roundworms, tapeworms, gapeworms, etc.||• open-mouth breathing|
• grunting sound
• difficulty breathing
|Infectious Bronchitis||Respiratory||• Reduced egg production|
• discharge from • the bird's eyes and nostrils
• laboured breathing.
more on infectious brochitis
| How to Prevent: Like fowl pox, there are a few types of preventative vaccinations against infectious bronchitis, but its not a guarantee. Having a good biosecurity method in place, as well as adequate rodent control should help keep the disease to a minimum.How to Treat: Unfortunately, theres not much that can be done for bronchitis. You can give your birds antibiotics for a few days to make sure no other infections happen while theyre sick, but otherwise you just have to wait it out.
How to Prevent: Like fowl pox, there are a few types of preventative vaccinations against infectious bronchitis, but its not a guarantee. Having a good biosecurity method in place, as well as adequate rodent control should help keep the disease to a minimum.
|Infectious Coryza||• swelling of the face around the eyes and wattles|
• nasal discharge
• swollen sinuses
• Watery discharge from the eyes
|Lymphoid Leukosis||Chickens with lymphoid leukosis have few typical clinical signs. These may include:|
• depressed before death
• enlarged bursa and liver
|New Castle Disease||Respiratory and nervous system||virus||• Egg laying stops.|
• misshapen eggs are produced with rough shells and sometimes bleached shells.
• In chicks, gasping coughing and sneezing
• Birds may be seen sitting on their back hock joints
• walking backwards or in circles
• putting the head between their legs
• breathing difficulties, nasal discharge, murky eyes
• paralysis in their legs and wings.Newcastle Disease
|Vaccinate chicks at 3 to 4 weeks of age. Repeat at 16 weeks of age and at the 24th week. Thereafter vaccinate when there is an outbreak in the area.Since the disease is carried by wild birds, keeping your flock vaccinated is very important. Its also recommended to practice good sanitation since a person can infect other birds via clothing or shoes.Birds will typically recover from ND and not be carriers, but if your chicks develop the disease, they will likely not survive. As with other diseases, you can give your birds antibiotics for a few days to avoid any other bacterial infections.|
navel illness, mushy chick disease
|• drowsy and droopy|
• Down(feathers) “puffed up”
• stand near the heat source
• indifferent to feed or water.
• Diarrhoea sometimes occurs.
• poorly healed navels
• bluish colour of the abdominal muscles
|Pullorum Disease||Intestine/Ovary||Salomonella Pullorum||• Chicks utter squeaky chirps|
• appear drowsy
• ruffled feathers.
• Vent smeared with faecal discharges.
• no external symptoms are seen in adult birds.
|Destroy all confirmed carriers of the disease.Clean and disinfect all the premises and incubatorsGet chicks from hatcheries with good disease control programme.|
|Coccidiosis||Stomach||coccidian||• Droopy wings|
• ruffled feathers
• pale beaks and shanks
• bloody diarrhoea
• weight loss.
|Sulphur drugs, coccidiostat in feedSince there are six species of Eimeria (the coccidiosis parasite), your bird may become immune to one kind, but contract another. You can treat this with antibiotics or other specific types of medication that will get rid of the parasite.- Vaccination
- add coccidiostat in feed
- dry litter
|Twisted legsPerosis disease||swollen, twisted, broken, or bowed legs, or loss of color in feathers, the comb, or the roof of the mouth.|
|Twisting Neck||• bird has difficulty balancing while standing because the neck twists,|
• bird tries to balance by permanently looking upwards.
|Ulcerative Enteritis (Quail disease)|
inflammation and ulcers in the cecum and liver
|Botulism||• Flaccid paresis of legs, wings, necks and eyelids|
• The paresis rapidly progresses to paralysis
• birds fall into a deep coma with neck and head typically extended forward.
|Cannibalism||chicken pecking each other||Occupy the birds by supplying grass in the unit for them to pick on. De-beak the birds if the problem continues.|
|CAPILLARIA (CAPILLARY OR THREAD WORMS)||severe inflammation of intestines|
Erosion of the intestinal lining
|Curly Toe paralysis||• unable to stand or walk|
• toes curled
|Egg eating||eating eggs laid by other birds or themselves.|
|HistomoniasisHistomoniasis||See blackhead disease|
|Infectious Bursal Disease (Gumboro)||Gumboro has no symptoms of its own. But infections leaves the chick's immune system dented and thus it susceptible to many other infections.|
|Infectious Synovitis||• swollen, red, and warm hock joints. |
• limping and difficult painful in walking.
|Marek's Disease||also referred to as fowl paralysis, |
• irregularly shaped pupils
• partial paralysis
|Since this poultry disease is a form of avian cancer, there is unfortunately not much that can be done for infected chicks. Its also contagious since its a virus and is transmitted when a chicken breathes in feather dander from another infected bird. If the bird survives, it will remain a carrier of the disease for life, so its best to remove it from the flock early.While this disease sounds scary, there are vaccines available. Newly hatched birds can be vaccinated for Mareks disease to help reduce the likelihood of infection.|
|Necrotic Enteritis||Stomach||• Swollen stomach|
• (postmotem: rotten intestines, foul smelling water in cavity)
|Quil brochitis||No signs in chicken but in quil:|
• respiratory distress, coughing, sneezing, rales
• nasal or ocular discharge
• Loose, watery droppings
|Scratching||Ectoparasites such lice, fleas, mites and bedbugs.||too much scratching with feet and beaks.|
|Species affected||Age affected||Symptoms||Treatment|
|Newcastle Disease (NCD)||Chicken, turkeys &|
|All||Depression, poor appetite, cough- ing and difficult breathing, diar|
rhoea, nervous signs, twisted neck
and death in large numbers in a
|Spreading eruption on comb, wat-|
tle nose & other featherless parts,
poor appetite/egg production, de-
pression. Deaths may result in
|chicken||all||Chicks/growers: Depression, hud- dling, poor appetite, coughing,|
gasping/difficult breathing, death.
Adult: Coughing/noisy breathing,
few eggs laid/with soft shells
|Chicken and tur-|
|All||Depression, coughing, discharge from eyes/nostrils, swollen face,|
poor sight and feeding, nervous
signs and diarrhoea
|Destroy sick birds|
|IBD||Chicken||2-6 wk||Depression, poor appetite, un-|
steady walk, pecking at vent and diarrhoea
|Control by vaccination|
|Salmonellosis||Chicken, turkeys,||Severe in chicks up||Dejection, ruffle feathers, dosing,||Vaccination
|ducks||to 3||huddle together in||sulphur|
|months,||chicks, poor appetite,||drugs (S-|
|moderate||thirst, soiled vents, and||Dime)|
|in adults||high deaths|
|Collibacillosis||Chicken, turkeys,||4-8 wk||Coughing, sneezing, dejection, poor||Antibiotics
|ducks||appetite, poor growth||and Sulphur|
|Chicken||Any age||Swollen face, sneezing and difficult breathing,||Antibiotics|
|loss of condition, low|
|egg production and|
Parasites are organisms that live on others without benefit to the host and include worms living in the opening of organs, and lice and fleas on the external. The parasites may cause diseases, weakening the system so that other disease-causing agents thrive or transmit diseases. Worms are internal parasites that inhabit the alimentary canal and other internal organs such as the proventriculus, gizzards, trachea, and lungs. There are 2 groups of worms, roundworms and flatworms (Fig. 6)
Roundworms Ascaridia galli infects both chicks and adult chickens. Eggs are laid by female worms in birds’ intestines and are passed out in droppings. They mature in one week or more after which they may be swallowed up by chicken, hatch and cause fresh infection. Clinical signs include slow growth (stunted), culled feathers and drooping head, thirst, low egg production and death due to intestinal obstruction in young birds. Due to their feeding habits, it is difficult to prevent this condition in scavenging chicken.
Gape worms Syngamus trachea roundworms infect the trachea (windpipe) of chickens. Adult worms live and lay eggs in the birds’ trachea; the eggs may be coughed out or into the oesophagus and swallowed in which case the hen passes the eggs in the stool. The eggs hatch to larvae which infect chicken or enter simple carriers (intermediate hosts) such as beetles and earthworms. Symptoms include difficulty in breathing and gasping for air, hence the term gapeworm, culling and huddling and death due to suffocation. The condition can be controlled by giving Thiabendazole or Gapex in drinking water.
Tapeworm Raillietina tetragona infests scavenging chicken. The worms pass eggs either as free eggs or retained in a segment. Intermediate hosts such as beetles and snails ingest the eggs or segments. The eggs develop in the host and in turn infect chicken that feeds on the intermediate hosts. Symptoms include stunting, thirst, poor health, low egg production and death in young birds on poor diets. It can be
prevented in scavenging chicken by using clean containers and drenching at 3- month intervals with Albendazole and Fenbendazole.
Isolation disposal of dead birds
Do not introduce new birds purchased from markets or given as gifts directly in to the flock. Keep them separate and observe them for at least one week. Sick birds should be confined away from the rest. Carcasses should be disposed of by burying at more than 3 feet underground.
Viruses are the smallest germs and cause incurable viral diseases. They should be prevented by early vaccination.
Newcastle disease is the most economically important and the only notifiable disease in chicken. It is spread by sick birds, dogs, wild birds and man. Symptoms include respiratory stress, lack of appetite, diarrhoea, nervous symptoms and high mortality. Sometimes death can be sudden without the symptoms (Fig. 7). Chicken that reach the tertiary stage showing nervous symptoms may survive but will always show lack of nervous co-ordination. The only way to protect chicken is by early vaccination.
Fowl Pox is a chronic disease in adult birds but acute and fatal among chicks and growers. It is caused by Pox virus and transmitted by mosquito bites and mechanically through broken skin. Clinical symptoms include pimples or scabs on the birds’ combs (Fig. 8), wattle and eyelids, a watery discharge from eyes, difficulty in breathing indicated by whizzing sound and loss of appetite. Mortality is low in adult chicken but high in chicks and growers. There is usually a drop in egg production in laying birds. The disease can be avoided by clearing bushes or controlled by vaccinating the chicken when they are 4 weeks old by wing web stab using a needle. Follow this by examining the vaccination site after 7 days for reaction. Pox virus can survive for 10 years in the soil. Since infected chicken are predisposed to secondary infections, infected chicken should be covered with an antibiotic treatment.
Fig. 7. (left) This hen did not show signs of sickness when it was put in the basket with chicks but died of acute Newcastle disease 4 h later. Fig 8. (right) A hen with Fowl Pox pimples on the comb
Infectious bronchitis is a contagious disease, acute in chicks and chronic in adult birds. The disease is transmitted from sick birds through faeces, litter and air. Symptoms in adults include sneezing and watery eyes, nasal discharge, wet droppings, and poor eggshell with no death unless from secondary infection.
Chicks gasp and cough, breath noisily, have watery eyes and nostrils, become depressed and huddle. Mortality can be as high as 25%. It is controlled by vaccinating with multiple serotype or covering with antibiotics during outbreaks.
Avian Influenza (Fowl plague) is an acute disease in chickens, ducks, turkeys and wild birds. It is transmitted through contaminated faeces, water and air. Symptoms include respiratory distress, sneezing, sinusitis (swollen head and face), emaciation and nervous disorder. Infected birds should be destroyed and the location of infection quarantined.
Infectious Bursa Disease (Gumboro) (Fig. 9) is common in hatcheries and birds are likely to be infected by the time they are acquired by the farmer. It is spread through feed, water and faeces. It affects young chicks aged 2-6 weeks. Gumboro is rare in indigenous birds. Symptoms include diarrhoea, sleepiness and depression, ruffled feathers, and trembling of the head. Mortality is between 50% and 80%. The disease causes immuno-supression, predisposing the bird to other infections. It can be controlled by vaccinating the chicken when they are 2-6 weeks old through drinking water.
Fig. 9. Death caused by Infectious bursa disease
External parasites of poultry
External parasites infest poultry houses and breed in cracks of the buildings. The species commonly found include lice, mites, fleas and ticks, though very rare. They affect all ages of birds but are severe in chicks. They are spread by infected birds and pets.
Lice lay eggs on the feathers and suck blood from chicken, causing discomfort.
Mites do not live on the host but in cracks in the poultry houses. They suck blood from the birds at night and return to the cracks during the day. In severe infections, birds become anaemic.
Fleas suck blood from birds after which they drop and lay eggs in the litter. The eggs mature to adult fleas. They can survive for up to a month without feeding.
External parasites can be avoided by maintaining cleanliness of the poultry nests and houses and sealing cracks in the walls and on the floors. They can be controlled by applying sevine powder, Malathion dust or actelic dust (Table 4).
Table 4. Disease occurrence and recommended treatment
|Disease||Species affected||Age affected||Symptoms||Treatment|
|Coccidiosis||All||2-6 wk and also older||Depression, ruffle feathers, poor appetite, poor growth,||Sulphonomide
s (S-Dime) and
|birds||diarrhoea with blood and||Amprolium.|
|Round w orms||All||Over 4 wk||Loss of condition, slow growth, littleness and||Levamisole and ascarex|
|diarrhoea, death in chicks|
|Gapeworm||Chicken,||3-12 wk not||Gasping for air, difficult||Levamisole and|
|breathing, poor appetite
and condition and death
|Tapeworm||Mainly chicken,||3-12 wk not severe in||Loss of condition, slow growth, droopiness,||Albendazole|
|Turkeys||older birds||inactive and littleness|
|Other worms||All||All ages||No signs of illness||Non|
|External parasites||All||All ages||Depression, etching and scratching sometimes- causing wounds, could be||Sevin powder|
|severe among chicks|
Good records of among other things amount and cost of chicken feed, vaccination, housing, household consumption and labour, help the farmer to assess the profit margins. Simple benefits analysis can be done by subtracting the cost of inputs from the value of outputs.
Article reproduced courtesy of KALRO (KARI)
The KARI Technical Note Series was launched to provide an outlet for the enormous amounts of technical work generated by KARI, some of it dating many years back, that has not been published in any of the institute’s existing publications including the East African Agricultural and Forestry Journal, the KARI Annual Report, the Highlighter and the KARI updates.