Studies on experimental water intoxication in calves
Abstract
water intoxication is a disease that affects all domestic
livestock species but most commonly reported in calves. The aims of
this study were to reproduce the disease in calves under
experimental conditions and to evaluate clinicopathologic changes
that occur in the course of the disease.
A total of ten two-week old calves, five in the test group and
five in the control group were used. Both groups were raised in
identical managemental conditions except that in the test group, no
water and salts were provided except that contained in the milk, in
the whole preweaning period. After an acclimatization period of two
weeks, body physiologic parameters were monitored, measurements
being taken once per week. The measurements included heart and
repiratory rates, and rectal temperature. Body weight was
determined once every two weeks. Blood serum, whole blood, urine,
and faecal samples were' collected once per week and laboratory
analysis of packed cell volum~ (PCV) , red blood cell (RBC) count,
white blood cell (WBC) count, total plasma proteins (TPP) ,
erythrocyte fragility, aspartate aminotransferase (AST) activity,
blood urea nitrogen (BUN), Na+, K+, urine volume, % faecal water
content, and urine specific gravity carried out. After the
induction of water intoxication in the test group, the animals were
monitored constantly and samples collected once per day. Two trials
of induction were carried at an interval of one month and in each
case, water was ingested voluntarily after provision ad libitum
Water intoxication was observed in all the test calves with
varying degrees of clinical manifestation. After the induction of
the disease for the first time, 4 out of 5 animals showed all the
signs of water intoxication with varying degrees of severity. After
the re-induction of the disease, all the animals suffered from mild
to severe form of the disease, and two of them died. There were
drastic changes in most of the parameters investigated. Body
weight, rectal temperature, and heart and respiratory rates
responded by a decr,ease. PCV, RBC, WBC and Na+ also responded by a
decrease while increases in TPP, erythrocyte fragility, AST, BUN,
K+, and urine specific gravity were recorded.
The results of this study were discussed on the basis of water
metabolism in the body. These results suggested that water
intoxication could be reproduced experimentally by restriction of
both salt and water, and restriction of these two components were
involved in pathogenesis of the disease in calves. The disease led
to drastic changes in blood constituents and most of these were
manifested in the clinical signs observed. from these study farmers
are advised to provide both salts and water from as early as two
weeks of age, and further study on water intoxication is
recommended.
Citation
Master of Science in Clinical StudiesPublisher
University of Nairobi Department of Clinical Studies