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Scour in Pheasants and Partridges:
Scour
(loose droppings) which may be either very watery, yellow and frothy, or black and blood
stained often results in sick birds and if they are not treated the birds rapidly loose
condition and may in severe cases die.
There are numerous causes of scour, some
of which are related to poor management, and it is important that the cause is identified
for suitable and effective treatment of the bird.
It
is not possible, simply by looking at the type of scour, to determine the cause. Not all frothy droppings for example signify
protozoal infection. If birds are treated
incorrectly then their condition continues to deteriorate and deaths are likely to occur.
Causes
of scour include the following: Viruses, Bacteria, Protozoa, Food problems and Poisoning.
Whilst
most birds will be able to cope with some level of potential disease causing organisms, it
is when birds are stressed that their immune system is unable to cope and scouring occurs. These stress factors can include rapid changes in
environmental temperature, poor weather conditions, overcrowding, bitting, food changes,
moving etc.
To try to prevent scour we need to either
reduce or eliminate the causal organisms and minimise the potential stresses on the birds.
Viral causes of scour:
Rotavirus
infection in birds of 3-14 days of age will often produce a very watery scour. Affected birds will huddle to keep warm and deaths
may occur. Rotavirus is however not the only
virus that causes scour and other viruses may cause similar symptoms.
People moving about the site easily spread
viruses and viruses spread rapidly within a hut once introduced. Overcrowding of chicks and poor environmental
conditions (excess humidity and poor temperature control) all contribute to making
conditions more severe.
There is no specific treatment for viral
infections but treating with re-hydration salts to prevent dehydration can help support
the birds. Acidifying the water is often also beneficial.
Bacterial Scour:
A
wide variety of bacteria can be recovered from scouring birds and these include Clostridia
and E.coli. In most cases the bacteria are
naturally present in the bird’s gut but do not cause any clinical disease until the
bird is under stress. Stresses that can
induce disease include overcrowding, rapid temperature changes and other disease
processes.
Affected birds are usually depressed and
may pass frothy droppings. Control of the
underlying stress factors together with antibiotic treatment and re-hydration salts are
effective in controlling the problem.
Protozoal Diseases:
a) Trichomonas
Trichomonas
is a normal inhabitant of the bird's gut but when present in large numbers it can cause
disease. Affected birds become depressed and pass yellow, frothy caecal droppings. The
Trichomonas organism is not known to produce a cyst and so disease does not persist on
land from one year to the next. Disease due to this organism is usually seen in birds
under stress and the removal of stress together with treatment with re-hydration salts and
possibly an antibiotic should be effective in controlling the condition.
b) Coccidiosis
Coccidia
are non-motile parasites and at least three different species are known to affect
pheasants with different species affecting partridges.
Affected birds may have loose droppings, they can rapidly loose condition and some
mortality may occur. Coccidial oocysts are
highly resistant and can survive on land for a long period of time even without any birds
being present. Once ingested their
numbers multiply rapidly within the bird so it is usual for game bird feed to have a
coccidiostat included. In birds exposed to
small number of these organisms a good immunity develops and it is usual for older birds
to be immune to disease.
Products
used to treat coccidiosis in poultry can also be effective in gamebirds.
Food problems:
There should be few problems with food
prepared by the game feed companies. If there
is a scour problem when birds receive a new batch of food and no other causes are obvious
on veterinary examination then a food problem may be suspected. If it is a food problem and the suspect food is
removed then the scour should rapidly cease. If
food is badly stored and fungal growths occur they can produce mycotoxins. These toxins can cause a wide variety of symptoms
that may be severe and can cause high mortality. Suspect
food should not be used. If a food problem is
suspected then a veterinary examination is required.
Poisoning:
Birds
may be exposed both to natural and synthetic poisons and in some cases these can result in
scour occurring. The diagnosis of these
conditions is often dependent on a good clinical history being taken and examination of
the bird’s environment is often necessary. Once
poisoning has occurred there are rarely any specific antidotes available and supportive
treatment of the birds is usually the best that is possible.
It can be seen that there are many causes
of scour in game birds and it is important that they are correctly investigated so that
appropriate action can be taken. Where
appropriate action is delayed birds can rapidly loose condition with mortality occurring
in the worst affected birds. It is not unusual for survivors to show signs of ill thrift
due to severe damage to the gut lining.
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