3
area between the Salt Range and the Kundian-Khushab Railway where the
water from the Salt Range collects in the rains ; and here they are abundant
in the monsoon. This new fact therefore does not materially alter our present
ideas on the Punjab Surra zones.
13. Another outbreak occurred in 1910, but this was in camels living in
Bikanir city and Gajner where one finds Stomoxys and Mosquitoes, as well as
Lyperosia. Veterinary Assistant Ata Mohamed was sent to deal with this
outbreak in November, assistance having been requested, A definite plan for
dealing with the disease has been suggested to the Bikanir authorities, parti-
cularly directed to diagnosis and segregation, for which latter there is plenty
of room in Bikanir.
14. It will be noted that this outbreak offers further support to the con-
clusion that Surra is chiefly spread by the biting flies, acting as mechanical
transmitters and that this severe outbreak occurred in the absence of Tabanus,
and therefore without the possibility of the trypanosome having gone through
any part of its life-cycle in that fly.
At Mohand it was noticed that the flies which carry infection most easily,
i.e., Tabanus, were less numerous than Haematapota and much less numerous
than Stomoxys, which can carry the trypanosome but with less ease ; in other
words, in comparing the practical importance of Tabanus and Stomoxys as
Surra transmitters the much larger numbers of Stomoxys probably largely
compensated for the comparative difficulty with which it transmits the disease.
Perhaps the same factor enables the Lyperosia to spread Surra in the desert
portions of Bikanir where it simply swarms.
15. SHAHPUR DISTRICT.—Tabanus found at Shahpur.
In Rakh Dharema, in August, Tabanus was found in parts, viz.:—near
the canal, and where rain-water collects as for instance Nikhi Niwan. I
could not find the fly on the higher lying parts of the Rakh, but in these
parts the grazing is poor ; altogether it must be considered rather unsafe for
camels in the Surra season.
16. MUZAFFARGARH DISTRICT.—In September a tour was made across
the Muzaffargarh Thal, from Muzaffargarh northwards to Wandara and thence
west to Kot Adu.
At Muzaffargarh itself Tabanus is found, but in the Thal there are none,
in fact in the Thal I rarely saw a biting-fly of any kind.
17. DERA GHAZI KHAN DISTRICT. Heavy losses among camels occurr-
ed in 1909 in the southern half of this district. I toured down it in Septem-
ber starting from Dera Ghazi Khan and going via Choti, Lalgarh, Dirigri,
Rajanpur to Rojhan. By your order a full report was made on this tour ;
the mortality was due to Surra, and occurred chiefly in camels of Lalgarh,
Rajanpur, and Rojhan and villages between the two latter places. It was
shown that Surra in Lalgarh camels should be preventable ; the camels should
return to Lalgarh before the onset of the rains, instead of remaining until
late in August in the neighbourhood of Fazilpur. Lalgarh has a good and
healthy grazing ground adjoining it.
The camels of Rajanpur, Kotla Hussan Shah, Umarkote, Budli and
Rojhan are more difficult to provide for. They cannot get out of reach of
the Wahs or Nullahs from the Indus until a certain amount of rain has
fallen, because the grazing in the desert to the west is otherwise insufficient to
sustain them ; consequently they have to wait in the Surra zone long after the
Surra season has begun. Tabanus is found even on the most outlying Wah,
and the area between the outermost Wah and the river Indus has long been
known to contain a very bad Surra zone. I found Tabanus plentiful 3 miles
to the north-west of Nawa Rojhan in the somewhat unlikely looking jungle
of Jal and Jhit.
Ration feeding in the desert until sufficient rain has fallen being rather
impracticable, I was only able to advise owners of camels in these places to
avoid the worst haunts of Tabanus and to segregate the sick. "With regard
to the latter, the camelmen will not consider an animal " sick " unless its
appetite is affected.
In camel Surra, in the first year of the disease there are often more
severe febrile attacks than later on and a large number die in a short time
from an acute form in which trypanosomes are rarely absent from the. blood ;