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Parasitism In Pygmy
Goats
by Mary Blankevoort, DVM
Parasites afflicting
goats can be broken into two major groups: 1) External
parasites (ectoparasites); and 2) Internal parasites (endoparasites).
[. . .]
Internal parasites
usually pose the more serious problem to the goat owner. The
underlying or initiating cause of severe disease in goats is
frequently attributable to some form of internal parasite. Most
of these worms and protozoans thrive and multiply in temperate
humid climates, particularly where animals are overcrowded.
When the nomadic desert goats were brought to such areas and
became domesticated, the environmental change upset the
tolerant equilibrium between the host and the parasite which
exist in the natural state. The organisms which had lived in
harmony with goats in the dry, hot, natural habitat were now
able to increase in numbers and their ability to cause disease.
COCCIDIOSIS
Members of the Coccidia group of parasites are not worms, but
rather protozoans (one-celled organisms) which can inhabit the
small intestine of nearly every species of bird and mammal.
Goat Coccidia are quite specific for goats; there is possibility
of cross-infection from sheep, but not from other species.
Suspect Coccidiosis when
a kid or kids develop diarrhea or soft stools, become anemic
and weak, and grow rough, unthrifty coats. Repeated bouts of
coughing and respiratory problems in the herd may also indicate
Coccidiosis. Have your veterinarian run a fecal exam, so that
the severity of the infection can be determined. Proper
treatment must be initiated immediately, consisting of oral
sulfa drugs (e.g. sulfamethazine) or Amprolium for the whole
herd. This can be in a food or water mix, or individually dosed
in the case of few or severely affected animals. Treatment
should be repeated every month until decal exams are
satisfactory. (The exams may never be negative, i.e. entirely
free of coccidia, even in a very healthy animal.)
Blood loss and
dehydration may be severe enough to require transfusions,
intravenous fluids, and intensive care. The disease can readily
kill a young kid.
The organism is shed in
the feces, and with optimum conditions of moderate
temperatures, some humidity, and shade, a Coccidia egg (oocyst)
can survive for up to eight months on the ground. Only sun,
drying, and extreme heat will insure natural control.
Therefore, the goat owner should provide raised or fenceline
containers for feed and water, sanitary removal of contaminated
bedding, good nutrition at all times, and avoidance of
overcrowding conditions. Parasites thrive in crowded herds.
When animals are housed in a barn, a thick bed of straw will
allow infective fecal pellets to drop down beyond the animal’s
reach; and frequent pasture rotation will let the sun kill the
bug in the closely cropped grass.
Initiate your Coccidia-control
program before young kids are turned out with the main herd;
this is when the little ones are usually exposed to the biggest
dose of parasite. Sulfa drugs may help at this time. Keeping
youngsters separated from the main herd until they are old
enough to become more resistant to the infection (at least four
months) will also be advantageous.
GASTRO INTESTINAL
NEMATODES (WORMS)
Unlike cattle, goats never develop strong resistance or
immunity to worms or to their effects. Kids are particularly
susceptible.
After the goat ingests
infective fecal material, a larval worm migrates through the
intestinal wall before attaching itself to the inner surface of
the stomach or gut, and a number of these larvae may lie dormant
for some time within the tissues, awaiting a suitable time to
emerge, such as the first few weeks of freshening, or a
nutritional deficiency, or any stressful occurrence which would
weaken the animal. I recently read about a case of an adult
pygmy doe who had died from an infection caused by these
dormant worms. The doe had been wormed and the fecal exams were
negative, but the worm larvae had not been touched by the
medication. (this, by the way, is the reason for deworming
twice, at two or three week intervals. By that time, the young
larvae, unharmed by the first dosing, will usually have
migrated to the intestinal lumen, where the second dosing can
reach them.)
During the migration into
the gastro-intestinal lumen, the worms mature and attach
themselves to the liming of the stomach or intestine, where
they damage the absorptive surface, interfere with digestion,
and suck blood from the gut wall. A heavy load of worms will
severely debilitate an animal, making it thin, anemic, and
unthrifty. Often the hair coat if wormy animals will be dry,
lusterless, and stands on end. The worm load may increase when
the goat has become sick for another reason, and/or when the
animal is moved from clean areas to highly infected premises.
A positive fecal exam
indicates the presence of adult, egg-laying worms in the
intestine, visible under a microscope; a negative exam is rare
in goats, but not impossible!
As with Coccidiosis,
control is two-fisted, clean environment being the more
effective weapon. Keep water and feed off the ground; if
possible, rotate pasture every two weeks; house very young
animals separately from mature stock (kids are less resistant
to worm loads); remove contaminated bedding, or keep animals on
inedible bedding materials.
Ideally, the use of worm
medication should be reserved for those times when the fecal
exams (done several times a year) justify its use. If the
laboratory work is not feasible, the following deworming
schedule should be followed: 1) Worm kids several weeks before
weaning. 2) Worm all stock at the beginning and at the end of
pasture season (spring and fall), and perhaps once more during
warm, wet weather. Pregnant does may benefit from the
appropriate medications several weeks before freshening. All
treatments should be repeated in two or three weeks to kill the
mature larvae.
[. . .]
LUNGWORMS
“Verminous pneumonia” is the term given to lungworms
infestation. It can be an insidious disease, often with fatal
consequences, even after the worms are gone.
Infective larvae are shed
in the feces after they have been coughed up from the lungs and
swallowed. Once re-ingested, they migrate through the liver on
their way to the lungs, often causing considerable liver
damage.
Egg-laying adult worms
inhabit lung tissue, causing a chronic, husky cough or bark and
serious secondary bacterial pneumonia. A fecal exam may tell if
there are active worms present, but if the exam is negative in
the presence of characteristic clinical signs (coughing,
pneumonia), have another sample checked a couple of weeks
later.
[. . .]
Control measures for
lungworms (species Dictvocaulus) are the same as for
gastro-intestinal worms.
Again, proper management
of feed, water, bedding, and pasture is key to good parasite
control. Healthy goats, vigorous kids, and good milk production
depend on these factors.
Excerpts from:
Hale, Lydia, and Ellen Kritzman, eds.
Pygmy Goats: Best of Memo
(1976-1981)
National Pygmy Goat Association: pp 74-76
This document is for
informational purposes only and is in no way intended to be a
substitute for medical consultation with a qualified veterinary
professional. The information provided through this document is
not meant to be used in the diagnosis or treatment of a health
problem or disease, nor should it be construed as such.
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