C.A.H.L.
- YOUR PARTNER IN ANIMAL HEALTH
COCCIDIOSIS
IN LAMBS
Cause
The incidence of coccidiosis has become an increasingly important problem
with the intensification of sheep production systems in recent years.
The organism s responsible are the coccidida and are members of a group
known as the protozoa. The oocyst which is found in the faeces, is a
parasite which infects sheep. Lambs become infected immediately they
are born as a result of sucking from their mothers, whose udder teats
are contaminated with faeces on the pasture or bedding. Two species
of coccidiosis are considered most serious in sheep, eimeria crandallis
and Eimeria ovinoidalis. The coccidial oocysts are swallowed by the
sheep and hatch in the gut, releasing active stages which invade the
cells lining in the gut. From hence the process of multiplication increases
rapidly causing severe damage to the intestine.
Coccidiosis occurs in young lambs, older sheep having become immune
through previous contact with the parasite. Outbreaks occur mainly in
lambs 4 - 8 weeks of age. The disease may occur also in flocks which
have been housed for a period and are then turned out on to pasture,
with cases occurring in lambs 2-3 weeks after turnout. Coccidiosis may
also appear in outdoor lambing flocks, where high stocking rates are
employed, which can lead to high faecal contamination of pasture, especially
around feed and water troughs.
Symptoms
The first sign of coccidiosis affecting the flock is that lambs may
not be thriving as well as expected. Observation of lambs will reveal
an open-fleeced appearance and dirtiness around the tail due to a mild
diarrhoea. The lambs in the flock begin to lose their appetite, become
weak and unthrifty. Further signs may become apparent as the condition
worsens, for example severe scouring and streaks of blood in the diarrhoea
followed by severe dehydration. In severe outbreaks fatalities are the
result. Financial losses accrue due to the poor growth rate of affected
lambs. Diagnosis will require consultation with your veterinary surgeon
whom may take a faecal sample and submit it to a veterinary laboratory
to determine the probable cause of illness.
Treatment
& Prevention
Treatment of coccidiosis is a tedious and expensive business however
a number of products are available for treatment. In-feed medication
is available for lambs which protect them from a very early age, however
there is always the risk that lambs will eat different quantities of
feed, especially if they are ill, so it's difficult to be sure that
they all receive the right dose. Injectable treatments such as sulphonamides
are available from your veterinary surgeon and are often used instead
of medicated creep feed or because previous medication has failed. The
drawback is that if you don't treat at all, until there is a problem,
coccidiosis and all its associated losses will already be occurring
within the flock. Injectable treatments often require multiple doses
making it stressful for lambs and potentially making them more susceptible
to further disease. Unlike other treatments there is a new answer to
lamb coccidiosis in the form of a oral suspension and is administered
with a drench gun. Contact your local veterinary surgeon for further
details.
