Ten simple rules for disease prevention:
1. Give access to the right feed and clean water, in particular for small chicks;
2. Build shelters against wind and rain;
3. Clean houses regularly and apply lime wash on the floor and the walls;
4. If necessary, provide dry litter regularly;
5. Do not put too many birds together;
6. Different species of poultry, for example hens, turkeys, pigeons, ducks and
guinea fowls should be kept separate;
7. Separate chicks from adult birds except from the mother hen;
8. Vaccinate chicks against the most important diseases and revaccinate if
9. Isolate and treat sick birds – if medication is not available then kill the sick
10. Burn or bury killed birds.
Very common during dry seasons, often seen in young chicks,
but also in adults. High flock mortality, of between 30% and 80% of the birds die,
when the disease hits. Chickens lose appetite and have poor digestion. They
might show heavy breathing, greenish droppings, and sometimes bloody diarrhoea .
They may show nervous symptoms, paralysis and die suddenly, and the symptoms
may occur all at the same time. The disease is a virus, so there is no treatment, but
it may be prevented through vaccination of all birds including chicks from two
weeks of age.
Avian Influenza (AI)
Found naturally in ducks and other waterfowl, and may spread as a
highly contagious and potentially dangerous form to chickens. High flock mortality,
blue and swollen comb and wattles. Infects through contaminated feed and drinking
water from ponds. The disease is a virus, so there is no treatment. Best prevention
is strict hygiene and slaughter of sick birds. AI can presently NOT be prevented
through vaccination of birds. Culling and burning of all birds in the flock and strict
cleaning of chicken houses must be considered after a disease outbreak. Always call
a veterinarian, if you suspect an AI outbreak.
*Do not eat infected birds.
Often seen in young chicks, but also in adults, and shows as pocks (small lumps)
on wattles, comb and face. High body temperature, tiredness followed by sudden
death. The disease is common during dry seasons, but may be found all year
around. The disease is a virus, so there is no treatment. Vaccine is available and
Seen only in birds older than 16 weeks. Initially the birds may show paralysis of one
or both wings. Or one or both legs might be paralysed. The disease is a virus, so
there is no treatment, but commercial vaccines are available.
E. coli infection
Common among newly hatched chicks, causing infection in the stomach region.
Symptoms in older birds: Respiratory distress or infection in the egg organ with stop
of egg production. The best prevention is improved hygiene of eggs for hatching
and of the nests. Treatment of sick chicks might be possible with antibiotics.
Fowl cholera (pasteurellosis)
May occur any time in all ages. Symptoms are severe diarrhoea, respiratory
symptoms, loss of appetite, blue combs and wattles. May occur as a chronic disease
or hit as sudden death. Infection through contaminated feed and drinking water.
There is no treatment. Best prevention is strict hygiene and vaccination.
*Kill and burn affected birds. Vaccine is usually available.
Pullorum disease (Baciillary white diarrhoea)
Usually in young chicks. Chicks walk with difficulty, show big bellies and drag their
wings. Faeces is liquid and turns white. There is no treatment. Prevention is strict
hygiene. If illness occurs, isolate or kill and burn the birds. Disease is transmitted to
chicks from the eggs of infected hens, which may not show signs of being ill.
Usually seen in older birds. Symptoms: high body temperature, tiredness, blue
comb, sudden death. No treatment. Prevention through strict hygiene and culling of
ill hens. Do not buy chicks from unknown sources, and do not use eggs for hatching
from hens that have been ill.
Gumboro (Infectious Bursal Disease, IBD)
Only seen in chicks younger than 6 weeks, and normally only in large flocks kept in
confinement. Not common in small-scale village based systems. Common
symptom: Diarrhoea. The disease is a virus, so there is no treatment. Vaccine is
Symptoms: Runny nose, swellings under the eyes, closed eyes, drop in egg
production. Treatment by adding antibiotics in drinking water.
Chronic respiratory disease (Mycoplasmosis)
Symptoms: Runny or blocked nose, swollen face, closed eyes, drop in egg
production, rare deaths. Treatment by adding antibiotics in drinking water.
Coccidiosis (internal parasites)
The disease may occur at any time at all ages, but can be prevented by regular and
careful cleaning of troughs and poultry houses. Symptoms: Sick, tired, head down,
ruffled feathers, bloody diarrhoea. Death in young chicks. If the chicks survive, they
will remain thin and be late in laying. Treatment: Anticoccidiostatics in drinking
water or feed. Prevention: Not too many birds together. Avoid different age groups
of birds in the same house, as the disease may spread from adults to young chicks.
*Diarrhoea may be caused by several diseases, but the looks and colour will differ.
Roundworms and tapeworms (internal parasites)
Internal parasites are very common in all ages in the village based production
systems. These parasites will cause poor health, weight loss, drop in egg
production, and bloody diarrhea. The best treatment is adding anthelmintics in the
drinking water once or twice a year, at best two weeks before vaccination against
Newcastle Disease. Careful hygiene may prevent heavy infection.
Attacks all ages any time, but occurs more frequently in humid chicken houses with
bad hygiene. Adult birds are clearly disturbed and spend a lot of time pecking and
polishing feathers. Young chicks may die from anemia. If not treated, mites, lice,
fleas, ticks will cause weight loss and possibly loss of feathers due to the parasites
sucking blood and to skin irritation. Lice can be seen around eyes and nose. Fleas
can be seen on the belly.
Treatment: Spray or dust with pesticides, ashes, and oil.
Ashes and sulphur powder may be used where the hens do dust bathing. Nests may
be protected by putting a few tobacco leaves mixed with ashes in the nests.
Scaly leg is caused by an external parasite irritating the skin on the birds’ legs.
Symptoms: Legs clearly have scales and wounds and may become crippled in their
appearance. Treatment: Dip the legs daily in kerosene, oil or in an insecticide until
the scales disappear.
Symptoms: Bone deformation and feather loss. The birds walk with difficulty; they
limp. Legs are deformed. Some deficiencies may cause feather loss. Treatment, if
detected in time: Supplementary vitamins and calcium, fresh grass, and cow dung.
Nutritional diseases may be avoided when the birds have access to normal
vegetation and are therefore rare in scavenging chickens.
Nutritional diseases. Feather loss (a) and leg deformation (b)
Mycotoxicosis (fungal poisoning)
Symptoms: Weakness, pale combs. Treatment: Supplementary vitamins. Prevention:
Proper storage of feed to prevent growth of the fungi producing mycotoxins, the
cause of the disease.
Good management = healthy birds
Medication and vaccination
Some diseases may be cured by drugs. Parasitic diseases, such as lice or worms may
be cured by use of anti-parasitic drugs or by applying simple methods such as
baths in oil. Some bacterial diseases causing diarrhoea, may be cured with
antibiotics. For viral diseases there is no treatment. But the viral diseases may often
be prevented by vaccination.
All poultry should be vaccinated against the most common viral disease(s) in the
area. Vaccination schemes at village level should cover Newcastle Disease and Fowl
Pox. Vaccination against Avian Influenza should be avoided, unless recommended
by veterinarian authorities. Other viral diseases such as Gumboro and Marek’s
disease may be covered by vaccination, but they are often less important at village
level. A bacterial disease such as Fowl cholera may also be prevented by vaccination.
Poultry should be vaccinated when they are very young, and before they have begun
to lay eggs. Most young birds that have not been vaccinated do not resist diseases,
and often die.
*Vaccines should only be given to healthy birds. If you vaccinate a sick
bird you may kill the bird.
Anthelmintics against internal parasites should be given two weeks before vaccination, to improve the effect of the vaccine.
There are four fundamental ways of vaccinating birds:
1. Eye drops
3. Skin piercing.
4. Orally (in feed or water)
For scavenging poultry, you should avoid mixing vaccines with drinking water or
feed, as it is difficult to give the right dose. Research have shown that protection
against e.g. Newcastle Disease is highly variable if vaccine is given through water or
feed. Giving the right dose is essential for the vaccine to work properly. A too high
dose of a live vaccine may kill a young chick, whereas a too low dose will not give
adequate protection. Thus, it is important to consult a veterinarian or auxiliary
veterinarians (barefoot vets, village vaccinators) for further advice before carrying
out a vaccination.
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