March 1955 ] G. S. RATHORE, P. D. MATHUR AND N. S. SANKARNARAYAN 13
OUTBREAKS OF HELMINTHIASIS AND CONTROL
As a further proof of the prevalence of helminthiasis in Rajasthan and the
efficacy of phenothiazine in controlling it, the following histories of mortality in
sheep are recorded here.
These outbreaks occurred mostly in Central Rajasthan, as marked in the map
opposite to page 4. They were heavy during 1952-53 as a result of successive
years of famine ; the animals loosing vitality and power of adjusting co-existence
between host and parasite. Grazing became scanty through failure of the rains;
flocks migrated in search of pastures to the adjoining States of U. P. and M. B.
and returned infested with helminths to spread the infestation. The outbreaks
started just after the earlier monsoon and continued until the beginning of summer
when the pasture became absolutely dry. In winter, helminthiasis, helped by dry
cold, famine and low vitality, also played havoc among the sheep. The outbreak
in the Government Sheep Research Farm, Jaipur, started just after the onset of the
monsoon. Dying sheep showed abdominal pain, grinding of teeth and circling
before collapse. No pyrexia was shown. Some showed diarrhoea and dysentery,
but a few succumbed before that stage. The most conspicuous sign was the pass-
ing of soft faeces consistent with that of a calf, sometimes with thick mucus and
tinge of blood. Faecal examination showed some dead worms which were con-
firmed by the helminthologist, Indian Veterinary Research Institute, as H. con-
tortus. Egg counts were upto 1,200 gm. which must be considered heavy.
Faeces for 24 hours were collected in hospital from one sheep after anthelmintic
and purgative treatment. H. contortus and O. columbianum were identified, the
former in larger numbers sufficient to cause acute haemonchosis. All animals
on the farm were given 10 gm. of ' Phenovis' which stopped further mortality.
These animals are specially looked after and are normally in good condition. They
are generally kept in separate paddocks away from infestation. Enquiry revealed
that they were taken during summer to graze on a neighbouring pasture where
village flocks also graze, thus becoming infested.
The second outbreak was at Sirohi and surrounding villages. The former
Sirohi State has a good rainfall and plenty of pasture, but, being a border area,
many flocks from Gujarat come there for grazing. The areas have thus become
enzootic and outbreaks occur yearly. In 1952-53 sheep and goats died from causes
then unknown. The history, epidemiology and signs were similar to the helmin-
thiasis noted above. Faecal examinations showed ova and larvae, the counts being
2,800 gm. (H. contortus with few T. ovis). Mass treatment with 'Phenovis' fol-
lowed by 10 c.c. doses of 5 per cent copper sulphate stopped deaths.
The third outbreak was at the sheep and goat asylum, Moklawas, situated in a
valley about 12 miles from Jodhpur and having a population of about 2,000 male
goats and sheep. This is a charitable institution to which animals, purchased from
butchers by the Jain community, are left to die a natural death. The animals
graze only in the area attached to the asylum with the result that many of them are
under-fed. Additional animals introduce infestation. The area is practically dry,
the only source of water being a well. The whole flock was heavily infested with a
mortality rate of 8 to 10 daily. The sick showed the same signs at first and in many
death supervened from pneumonia. Post mortem examinations showed numerous