Agriculture Reference
In-Depth Information
it is emptied too quickly. If the stone cannot be dislodged, a veterinarian may
administer a smooth-muscle relaxer, which has a dilating action that allows
the calculi to pass, or remove the stone surgically.
Any of the following can contribute to calculi:
■
Low water intake due to cold weather or unpalatable water. Lambs need
fresh, warm water during cold weather. Adding salt to the ration and
keeping both salt and fresh water in the creep helps. Increasing salt
increases urine volume and decreases the incidence of stones; sheep
that don't have access to salt do not drink suffi cient water, especially in
cold weather.
■
Ration that has excessive phosphorus and potassium — like beet pulp,
wheat bran, and corn fodder — but is low in vitamin A. Correct this by
adding ground limestone, 1 or 2 percent of the ration, to make the cal-
cium-phosphate ratio approximately 2:1. Well-formulated lamb-feed
pellets have this ratio.
■
Ration that has excessive calcium, such as a diet of pure alfalfa.
■
Growing crops by using a heavy fertilizer with high nitrate content. This
practice interferes with the carotene roughage that produces vitamin A.
Enrichment of the ration with vitamin A counteracts this problem.
■
Hard water. This problem can be corrected by adding feed-grade ammo-
nium chloride to the ration, approximately
1
⁄
5
ounce (6.1 mL) per head
per day. This salt is harmless and is found in some pelleted feeds.
■
Feeding of only pelleted feed. Urinary calculi seldom develop in lambs
who receive 20 percent alfalfa.
■
Hormonal changes that occur when ram lambs are castrated at less than
4 weeks of age. The absence of testosterone after castration keeps the
urethra from growing to its maximum diameter. If you have a persistent
problem with your wethers, try castrating after 6 weeks.
■
Feeding sorghum-based rations. Cottonseed meal and milo also increase
the risk of calculi. Corn and soybean meal are less apt to cause problems.
White Muscle Disease
Selenium again! White muscle disease, also known as “stiff lamb,” is caused
by a lack of it. If the soil is defi cient in this important mineral (as in parts of
Montana, Oregon, Michigan, New York, and many other areas), then so is
the hay. Hay from localities known to have inadequate selenium should not
be fed to ewes after the third month of pregnancy or during lactation, unless
