March, 1949]
M.
S.
RAJENDRAN
61
RESULTS
Verminosis
The greatest trouble that was encountered just before and after the commence-
ment of the experiment was the death among the calves at very short intervals,
11 out of a total of 14 deaths had occurred within a period of two months (from the
18th April 1944 to the 19th June 1944). A large majority of the animals that died
both before and after the commencement of the experiment showed clinical symptoms
and post-mortem appearances of verminous infection and they were the youngest
of the whole lot. However, when the animals attained the age of one year and
more and when there was marked improvement in their condition under better
feeding, care and management, mortality from verminosis stopped. There were but
three deaths for the whole of the remaining period of the experiment, i.e., 18½ months,
but the clinical symptoms and post-mortem appearances in these three were quite
different from those of the previous 11 deaths.
In all the above 11 cases, there were typical clinical symptoms of verminosis
before death. In seven of them, the worms collected at post-mortem, from the
fourth stomach were identified as Mecistocirrus digitatus or Haemonchus contortus;
thus detection of strongyle eggs in their dung earlier as evidence of verminosis
was confirmed at autopsy. It was noteworthy that not a single worm of Ascaris
species was found and not a single specimen of dung was found to contain eggs of
Ascaris species even though specimens of dung from each animal were examined
regularly throughout the period.
The response shown by the. animals suffering from parasitism, particularly
with strongylosis, is worthy of attention. It was, however, not possible to save
many of these diseased animals from death since in all these, the parasitic infection
was so advanced as to cause exhaustion, lowered vitality, anaemia, etc. Every
animal that was treated for strongyles with copper sulphate and that died subse-
quently within a few days of treatment, had no worms at all in the fourth stomach;
in a few cases when the period between the treatment and death was short, post-
mortem examination revealed either dead or disintegrated worms in the fourth
stomach (in one case they were found just at the commencement of the duodenum);
whereas in every case that was not treated, numerous worms were discovered in
the fourth stomach during autopsy and they were identified as Mecistocirrus
digitatus or Haemonchus contortus. Four of the seven animals that died after the
actual commencement of the experiment on 1 May 1944. died carly during the
experimental period, i.e., from about the fourth to sixth week. Except in one in
which there were a good number of Haemonchus contortus (this was an untreated
case in Group A), no worms were encountered at the time of the post-mortem
examination in the other three. The deaths in these cases are considered to be
due to the after-effects of strongyle infection coupled with the poor anaemic and
exhausted condition of these animals at the beginning of the experiment. That
parasitism is particularly harmful in the early age of an animal is again proved
by these findings; in addition, it has to be stressed that treatment, to be effective
against parasitism, must be undertaken in the early stages of the animals' life, i.e.,
before it is a year old.
N 2