EP 321
Symptoms
Does and ewes suffering from pregnancy toxemia (ketosis) appear
lethargic, sluggish and often fail to eat. The first symptom noticed in
does and ewes is an unwillingness to eat. They become depressed, weak and
have poor muscle control and balance later in pregnancy.
Many times, when they lie down, they are unable to rise. Early in the disease,
does or ewes will show a positive test for ketone bodies in the urine. The
breath of does and ewes will have a sweet or foul smell. Ketone bodies are
by-products of fat breakdown found in the blood and urine. Test kits are
often available for ketone bodies and they are easy to use.
Cause
Pregnancy toxemia is caused by the sudden extra demand for energy
by the fast-growing kids or lambs in the last few weeks of pregnancy. Seventy
percent of fetal growth occurs during the last few weeks. The disease is
not normally observed in ewes carrying singles. It is usually seen when
the ewe is carrying two or more lambs. Does and ewes that are too fat often
will experience pregnancy toxemia. At the time when the kids or lambs are
growing very rapidly, increasing amounts of space and energy are needed,
in addition to the protein and energy needed for maintenance of the doe
or ewe. The increase in feedstuffs high in energy must be supplied on a
daily basis. Does or ewes consuming large amounts of hay need a greater
internal space in the rumen, which causes decreasing space for growth of
the kids or lambs in the uterus. In meeting the nutritional needs of the
kids or lambs, the doe or ewe will metabolize or break down fat resources
from her body to maintain pregnancy. This rapid breakdown of body stores
of energy produces ketones (a toxic by-product) and you soon observe the
symptoms of the disease. Maintaining does or ewes in a medium body condition
rather than overly fat condition early in pregnancy will help keep down
the disease.
Transmission
Pregnancy toxemia is not a transmittable disease from one doe or
ewe to another, however, flocks or herds experiencing the disease may appear
to be infectious because the plane of nutrition and management throughout
pregnancy is similar. This shortage of energy in the diet may cause these
symptoms in several does or ewes, especially those carrying twins or triplets.
Treatment and Prevention
The treatment of pregnancy toxemia is usually unsuccessful. Providing
energy in the form of molasses or syrup generally does not suffice. Treatment
with propylene glycol at 60 to 90 ml (2 to 3 oz) twice daily may help. Cesarean
section to deliver the kids or lambs early will
sometimes save the doe or ewe and the kids or lambs if they are near term.
Corticosteroids may be used to abort the doe or ewe to prevent the loss
of the dam. Kids or lambs will die shortly following the diagnosis of pregnancy
toxemia due to lack of nutritional transfer from the doe or ewe to
them. The sooner the kids or lambs are born, the less likely the doe or
ewe will die.
Grain is a high source of available energy. Feeding 1-2 lbs. of grain daily
along with high quality legume hay during the last four to six weeks of
pregnancy will help prevent pregnancy toxemia. If the does or ewes are large,
it may be necessary to increase the grain from 50% to 100%. Feeding grain
first and having ample space at the feeders for each doe or ewe to get her
share of the grain followed by hay feeding may help. Protein requirements
should also be balanced, but protein level in the feed is not related to
pregnancy toxemia. Exercising the doe or ewe is quite helpful especially
in the cold winter months when feeding is in drylot. Hay can be placed in
feeders quite a distance from the barn to force the does or ewes to walk
to the feed to increase their exercise.
EP 321