March, 1954]                                 A. K. VARMA                                     27

treatment of these animals in the recent past. The area being in the same Kosi
belt has more or less identical topographical conditions in relation to the molluscan
habitats. Some Limnaea and Planorbis snails were collected and examined for
cercariae with negative results.

Purnea area

Faecal samples from 92 animals (34 cattle, 42 buffaloes, 10 goats and six sheep)
were examined and 20 (58.8 percent), 30 (71.4 per cent), five (50 per cent) and four
(66.6 per cent) were respectively found positive for fasciola infection. There was
no evidence of any anthelmintic treatment of these animals. One adult cattle was
examined post-mortem, but no fluke was recovered. Autopsy of two buffaloes yielded
several hundreds of flukes and paramphistomes from the bile ducts, which were
found very badly infested.

Due to shortage of time snail-searches could not be undertaken; but the topo-
graphical features of the area have similarity with the aforesaid localities, as the Kosi
was flowing through this area some years ago and when it worked its way westward
it left behind many water-pockets for the snail-hosts of the parasite.

                        TABLE VII

Summary of the incidence of fasciola infection

Locations

Total number
of animals*
examined

Total number

found positive

for infection

Percentage

of

infection

C B G

C B G

C B G

Supaul

68 82 28

32 65 22

47 79 78

Saharsa

18 23 7

10 19 5

55 83 71

Purnea

34 42 10

20 30 5

59 71 50

Grand total

120 147 45

62 114 32

52 77 71

* C=Cattle

B=Buffaloes

G=Goats

                                            DISCUSSION

From the foregoing data it is quite conceivable that the incidence of infection
varies considerably in different categories of susceptible animals. It was found to be
highest in buffaloes and lowest in cattle, the goats coming intermediate. This
phenomenon is apparently attributable to the grazing habits of these herbivora,
rather than to any selective affinity of the parasite for any particular host. Buffaloes
are voracious feeders and on account of their aquatic habit of grazing on grass grow-
ing over swamps, are comparatively more exposed to infection. Cattle have a

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