NationalLibraryOfScotland/medical-history-of-british-india huggingface dataset:
S. N. VAIDYANATHAN 41
THE PARASITIC GENERATION
No infective experiments were conducted. Only females of the parasitic
generation were recovered. They were mostly found in the first few feet of
the small intestine of the host. Up to the present time males have not been
found. It is interesting to note that the rare males, Kreis [1932] found in
the freshly passed exudates of a human case and a dog infected by him with
a human strain of Strongyloides stercoralis, are described as of the rhabditi¬
form type; perhaps further investigation may reveal them in the hosts of
Strongyloides papillosus as well.
THE PARASITIC FEMALE
(Figures 7, 9, 11 and 12)
It is long and filiform as all the parasitic adults of the genus. The cuticle
bears fine striations which are resolvable only under an oil-immersion
objective. Situated around the mouth are six papillae. The oesophagus is
simple and almost cylindrical. There is no definite relationship between
the total length of the worm and the length of the oesophagus ; it may roughly
be said to vary from a seventh to a fifth of the worm. It is without a poste-
rior swelling and contains well developed oesophageal glands. The tail is
bluntly rounded and finger-shaped. The vulva, a transverse slit with rather
salient lips, is situated posterior to the middle of the body which it divided
approximately in the proportion of five to two. The gonad is double and is
composed of an anterior and a posterior loop. Sandground [1925] draws
attention to the disposition or course of the ovaries in the parasitic generation
which affords a good diagnostic feature for certain species of Strongyloides
and shows that they are twisted or simple hair-pin bends. In Strongyloides
papillosus both the anterior and posterior loops of the ovary are twisted
round the intestine which serves as the axis.
Measurements
Length of the parasitic female
Maximum thickness .
Vulva to tail end
Ova (intrauterine) . .
3.5 to 6.5 mm. .
0.05 to 0.06 mm. .
....
0.035 to 0.045 mm.
by
0.024 to 0.028 mm.
Average
5.75 mm.
0.55 mm.
1.7 mm.
42
Incidence of Strongyloides papillosus Wedl, 1856
Strongyloides papillosus (Parasitic adult)
FIG. 11. Tail end.
FIG. 12. Region of the vulva
THE RHABDITIFORM (FREE-LIVING) FEMALE
(Figures 6 and 13)
It is a small form comparatively stout. The cuticle bears distinct
annulations. A short cylindrical buccal capsule is present in the young form
but in the older ones the presentation is complicated. Oesophagus is club
shaped connected by a narrow neck with a pyriform posterior bulb. The
tail is long and tapering. The vulva in the young female is situated just a
little behind the middle of the worm and gets nearer or in front of it in the older
ones. It opens directly into two uterine branches which are opposed. Ovaries
S. N. VAIDYANATHAN 43
are reflexed. Young females found after two days in faeces cultured at 27°C.
laid segmenting eggs but older females passed embryonated ones or even
active larvae. The eggs laid were thin-shelled and a shade larger than those
passed by the parasitic adults. They showed variations in size, those embry-
onated being much larger than those segmenting.
Average measurements of the rhabditiform (free-living) female from a
calf faecal culture
Length of rhabditiform (young) female . . .
Maximum thickness
Length of oesophagus
......
Length between anus and tip of tail
....
1.125 mm.
0.042 mm.
0.165 mm.
0.125 mm.
FIG. 13. Free-living female
44
Incidence of Strongyloides papillosus Wedl, 1856
THE RHABDITIFORM (FREE-LIVING) MALE
It could not be detected during the culture studies made with calf faeces.
The free-living males are reported to be more common in faecal cultures of
rabbits harbouring Strongyloides papillosus. Infection of rabbits is con-
templated ; the one attempted failed.
PATHOGENESIS
Strongyloides papillosus occurs in cattle, sheep and goats, many wild
ruminants and the rabbit. In sheep it is not considered very pathogenic,
many being harboured without apparent ill-effects. In the mink, from which
similar forms are recovered, heavy infections are found to cause serious trouble.
During post mortem of a dozen calves counts varying from a few to a
thousand-and-five-hundred of these worms, in the small intestine, have been
detected. It should be possible in the tropics, for young stock to get very
heavily infested with these worms. Few of the young calves escape being in-
fected as findings show. Unthriftiness among calves is common and in the
absence of other accountable causes, it may be useful to investigate if that
could be attributed to parasitism by Strongyloides.
IMMUNITY
There seems to be an age immunity of cattle against Strongyloides judg-
ing from the results of faecal examination of calves and full grown cattle.
Sixty per cent of 150 young calves were found infested with Strongyloides
papillosus; but no infection was observed in 400 adults aged two years and
over. It appears that infected calves quickly cleanse themselves with the
growing of age.
ACKNOWLEDGEMENT
The author is indebted to Rao Sahib M. Anant Narayan Rao, Lecturer
in Parasitology, Madras Veterinary College, for helpful criticism, facilities
and guidance, generously given for this piece of work.
REFERENCES
Bavay, A. (1876). Sur l' Anguillule stercorale, C. R. Acad. Sci., Paris. 83 (15), 694-696
Faust, E. C. (1937). The life-cycle of Strongyloides. Papers on Helm. published in
commemoration of the 30 year Jubilee of K. J. Skrjabin. pp. 160-165. Moscow :
Lenin Acad. Agri.
Sci.
Kreis, H. A. (1932). Studies on the genus Strongyloides. (Nematoda) Amer. J.
Hyg. 16, 450-491
Pagenstecher, H. A. (1865). Die Trichinen.
Nach Versuchen im Auftrage des Gros¬
sherzoglich leaidischen Handelsministerimus ausgefiihrt am Zoologischen Institut in
Heidelberg. Leipzig. 116 pp.
Ransom, B. H. (1911). The nematodes parasitic in the alimentary tract of cattle, sheep
and other ruminants.
Rogers, P. (1939). A new species of Strongyloides from the cat. J. Helm. 17, No. 4
Dec. 1939, 229-238
Sandground, J. H. (1925). Speciation and specificity in the Nematode genus Strongy-
loides. J. Par. Vol. XII No. 2 Dec. 192 .59-80
Ware, F. W. (1923). A fatal case of Strongyloides stercoralis infection in the dog. J.
Comp. Path. Therap. 36, 108
Wedl, C. (1856). Uber einiger Nematoden.
Sitzungb. K. Akad. Wiss. Wien, Math-
naturw. Clas., 19, 122-134
Zilahy, A. (1936). Strongyloides species parasitic in cattle. Thesis. Budapest.
EXPERIMENTS ON THE PERMEABILITY OF THE GOAT'S
PLACENTA TO RINDERPEST VIRUS
BY
M. K. SREENIVASAN, G.M.V.C.
Imperial Veterinary Research Institute, Mukteswar
(Received for publication on 11 September 1941)
T HERE is little in the relevant literature to suggest that the placenta is
readily permeable to filterable viruses. In some virus diseases, e.g.
rabies, it has been shown that infection can take place in utero. Thus
Konradi [1916], from transmission experiments on guinea-pigs, draws the
conclusion that rabies virus can be transmitted via the placenta but that,
in serial experiments, virulence gradually diminishes. This appears to
hold good also for dogs and other species of animals. Lanfranchi and
Lenzi [1918] demonstrated that rabies virus, apparently unaltered in
virulence, was present in the central nervous system of seven pups removed
from a bitch that died of dumb rabies, all rabbits inoculated with spinal cord
material from the bitch and the pups separately dying of typical rabies. This
appears to show clearly that the virus had traversed the placental filter.
Mrowka [1914] noted lesions, assumed to be those of rinderpest, in the
abomasum of newly-born calves and surmised that the infection had been
contracted in utero. He concluded that this might explain the insusceptibi-
lity of Asiatic cattle to rinderpest. No experimental evidence, however, was
given in support of this view.
Edwards [1927] carried out a series of experiments in sheep with rinder-
pest virus on lines similar to those undertaken in Germany by Beller and
Tahssin Bey [1926] who found that, when cultures of bovine pleuro-pneumonia
' virus ' were injected into sheep, complement fixation tests with the blood
serum indicated somewhat prolonged survival of the virus in some obscure
situation in the body. Some pregnant sheep after infection in this way,
aborted, and bacteriological and pathological examinations revealed that the
virus had become established in tissues of some of the foetuses, setting up
lesions closely resembling those of the natural disease in cattle, although no
trace of infection could be found in the maternal tissues. In the experiments
of Edwards [1927] pregnant sheep, inoculated with bovine rinderpest
virus, were used. At prescribed intervals the sheep were killed, and the
maternal blood and foetal juices and tissues tested separately for virulence by
inoculation into susceptible hill bulls. It was found that the virus persisted
in the maternal blood for some weeks after infection, but its persistence was
irregular, and there was no evidence of its being established in the foetal
tissues. The foetal envelopes thus appeared to be an effective barrier against
the penetration of a possibly somewhat enfeebled virus into the foetal circula-
tion.
It may also be mentioned here that Banerji [1933] observed that the milk
of cows, inoculated 5 to 10 days previously with rinderpest virus, was infective
45
D
M. K. SREENIVASAN 47
inoculated on 13 July 1939 into two healthy hill bulls, Nos. 85 and 73. Both
bulls remained healthy and on the 17th day a test dose of bull virus was inject-
ed. Both reacted severely to rinderpest but survived.
V. Goat 411 died on the 8th day after rinderpest virus inoculation. A
nearly full-grown foetus was removed immediately after death. Spleen pulp
and blood from this foetus were inoculated on 18 March 1936 into healthy
hill bulls, 720 and 727. There was no reaction in the bulls, and on the 14th
day they were tested with bull virus. Both developed rinderpest, but
survived.
CONCLUSION
The experimental data detailed above do not support the contention
that the placenta of the goat is permeable to rinderpest virus.
ACKNOWLEDGEMENT
My thanks are due to Mr J. R. Haddow, O.B.E., B.Sc., M.R.C.V.S.,
D.V.S.M., I.V.S., Deputy Director, Imperial Veterinary Research Institute
Mukteswar, for his encouragement.
REFERENCES
Banerji, P. C. (1933). Proc. 20th Indian Sci. Cong., 388
Banerji, P. C. and Mohan, R. N. (1935). Indian J. Vet. Sci. & Ani. Husb. 5, 64
Beller, K. and Tahssin Bey, S. (1926). Arb. a. d. Reichsgesundheitsamte 57, 484
Curasson, G. (1921). Rev. Gen. Med. Vet. 30, 569
Edwards, J. T. (1927). Trans. 7th Cong., Far East. Assoc. Trop. Med. 3, 699
Konradi, D. (1916). Ann. Inst. Past., 30, 33
Lanfranchi, A and Lenzi, F. (1918). C. R. Soc. Biol. 81, 396
Mrowka, F. (1914). Z. Infektkr. d. Haust. 15, 139
D
A CHEAP AND ACCURATE HOME-MADE AUTOMATIC
PIPETTE
BY
JOHN B. POLDING, B.Sc., M.R.C.V.S.
Imperial Veterinary Research Institute, Mukteswar-Kumaun
(Received for publication on 22 August 1941)
(With three text-figures)
I N many bacteriological laboratories, certain routine technique can be
simplified by employing an automatic distribution apparatus. Such
an apparatus is particularly useful in filling antigen when numerous agglutina
tion tests are to be performed. Instruments may be purchased from manu
facturers but they are costly and, in the writer's experience, not always satis
factory. Home-made apparatus is often fragile and requires delicate adjust
ing and maintenance. The instrument about to be described costs only a
few shillings and can be made by a good machinist in two or three hours.
It is not easily damaged and, once calibrated, remains accurate indefinitely.
In addition, it can be operated by unskilled labour and, by the simplest inter
change of parts, can be made to deliver any predetermined quantity from 0.25
c.c. to 10 c.c.
The instrument is essentially a pump and consists of two parts—a valve
chamber with valves (Fig. 1) and a cylinder with piston (Fig. 2). This form
of construction is admittedly not new but its appeal lies in its simplicity,
strength and cheapness.
CONSTRUCTION OF VALVE CHAMBER AND VALVES (Figs. 1 and 2)
The valve chamber is made from the barrel of a discarded 5.0 or 10.0
c.c. all metal syringe, as follows :—
(i) The syringe is taken to pieces and a short section of small bore nickle
tube is soldered into the external aperture of the barrel cap (Fig. 1, valve
cap A). This portion will in future be referred to as valve Cap A. (ii) A
section measuring 1½ in. from the open end of the barrel is cut off and the
nozzle end of the barrel is discarded. It will be noticed that one end of this
section is already screw-threaded. The opposite end should now be threaded
in like manner. This section of barrel is referred to as the valve chamber
(Fig. 1). (iii) Two collars to fit the bore of the valve chamber are cut from
⅛ in. brass plate and a ¼ in. hole bored through their centres. They are
soldered, one in each end of the valve chamber, to fit flush with its edges.
(iv) The wall of the valve chamber is pierced in the middle of its length and
the butt of a large record-type needle is soldered into the hole so made.
(v) A cap to screw on the newly threaded end of the valve chamber and
identical in shape with the nozzle cap of the discarded piece of barrel is turned.
(The old nozzle cap of the syringe cannot as a rule be modified for this purpose,
as, having been sweated on the barrel, it is just too large to take a thread
which will screw on to the valve chamber). The inner face of the cap is
fitted with a fibre, or hard rubber washer ⅛ in. in thickness and bored in
the centre with a ¼ in. hole. This cap is referred to as valve cap B (Fig. 1).
48
JOHN B. POLDING 49
FIG. 1.
Valve chamber with valves
FIG. 2. Construction of valves
50
Automatic Pipette
Valves are prepared as follows :
A piece of football bladder, cycle inner tube or sheet rubber of similar
thickness is obtained. It should be flat and unperished. From it are cut
two discs of the same diameter as the valve chamber. Each disc is marked
with pencil along two diameters at right angles to one another. The disc is
folded along one diameter and, in the centre of this fold (i.e. where it is
traversed by pencil mark of the other diameter), it is ' nipped ' with a sharp
pair of scissors for a distance of about 2 mm. In making this ' nip ', the
scissors should form a small angle with the edge of the fold, the angle being
big enough for the scissors to cut right through the rubber, producing a 2 mm.
flap covering the aperture so made. The disc is unfolded and forms the
completed valve (Fig. 2).
The valve chamber is now ready for assembly and is placed vertically
with the newly threaded end uppermost. A valve disc is placed against the
lower end of the valve chamber with its valve flap opening freely upwards
into the hole in the lower collar. Valve cap A is screwed on to this end of
the valve chamber, so that the valve disc is squeezed flatly between the collar
and the inner face of the cap.
The upper valve disc is fitted in the same way between the upper collar
of the valve chamber and the fibre washer placed on the inner face of valve
cap B. The flap of this valve should open freely upwards into the central
hole of this washer.
The apparatus in position for assembly, but not screwed together, is
shown in Fig. 1.
FIG. 3 Cylinder with piston
CONSTRUCTION OF PISTON AND CYLINDER (Fig. 3)
The piston and cylinder are made from an ordinary record syringe and
different sizes may be prepared depending on the quantity of fluid to be
delivered. When 0.25 to 0.5 c.c. quantities are required, a 1 c.c. syringe is
used, for a 1.0 c.c. delivery a 2 c.c. syringe and so on. The syringes are in
no way damaged and may be used for ordinary purposes when not employed
in this apparatus. The construction, and calibration of a 1 c.c. syringe for
0.5 c.c. quantities are described but the methods are the same for all sizes
of syringe.
Strips of brass foil are obtained. These can be conveniently made from
the flattened butts of discarded electric bulbs. A strip, in width rather
52
Automatic Pipette.
(3) Once in six months the plunger of the record syringe may be faintly
smeared with vaseline.
(4) If at any time the head of liquid is lost, the system must be primed
by suction before it will pump.
(5) The valves may be tested occasionally by removing the beaker of
saline. When this is done, no drip should occur from the suction pipe in
valve cap A. If a drip occurs, it shows that the valves are either stuck or
perished. If the former, the flap must be freed, and if the latter new ones
can be made and fitted in a few minutes.
TREATMENT OF EQUINE SURRA IN ASSAM*
BY
V. R. GOPALAKRISHNAN, G.M.V.C., P.G. (Mukr.)
Veterinary Investigation Officer, Assam
(Received for publication on 2 January 1940)
T HE method of treatment of surra in equines, as followed in Assam,
is described in this paper and a brief review is also made of other
methods of treatment for comparison. It is well known that a great
deal of work has been done on the chemotherapy of equine surra due
to infection with Trypanosma evansi, as the disease causes very heavy mor-
tality. Assam has sustained periodic losses due to infection with this parasite ;
particularly in equines and bovines. The climatic and geographical condi-
tions of Assam would appear to be favourable to the propagation of the
infection.
The province consists of two main valleys—the Brahmaputra and the
Surma. The climate is humid and the rainfall is very high. Large areas
of land, often inundated in rains and floods, consisting of swampy soil mostly
overgrown by weeds and rough grass usually fringe the permanent culti-
vated land. Some of these areas constitute the grazing reserves for large
herds of cattle. In addition, there are numerous hill ranges and vast forest
areas intercepted by riverain and low-lying marshy tracts. So much so the
seasonal occurrence of numerous parasitic infections is quite common. The
incidence of equine surra has been fairly high and as usual in other parts of
India, it is mostly prevalent in the rainy season (vide Table I). During
the season the transmitting agents of surra—Tabanus and Stomoxys flies—
are very numerous. The 'reservoirs' of the infection—cattle, buffaloes
and wild deer, are always there. Therefore it will not be surprising that on
certain occasions extra staff had to be employed to combat the disease breaking
out in enzootic form.
METHODS OF TREATMENT
Ever since the disease was known to occur, various attempts at treat-
ment have been made. A variety of drugs have been tried, alone or in com-
bination with others. The most important ones were the preparations of
arsenic [Lingard, 1899 ; Holmes, 1908, 1910] and antimony [Leese, 1910 ;
Cross, 1914, 1920]. The details regarding the treatment of surra with
arsenicals and tartar emetic are too well known to deserve repetition.
A remarkable advance in the chemotherapy of surra was made in India
by the introduction of the form of treatment with Naganol—' Bayer 205 '
[Edwards, 1928]. The routine line of treatment, immediately on micro-
scopical confirmation of the disease, was to inject 50 c.c. of a 10 per cent
solution of ' Bayer 205 ' intravenously, per 1000 lb. body-weight and 20 c.c.
of 0.1 per cent solution intrathecally. Fifteen days afterwards the intra-
thecal dose only was repeated. Again a fortnight later the full intravenous
*Read at the Indian Science Congress held at Benares in January 1941.
53
V. R. GOPALAKRISHNAN
55
Experiments were conducted in Bombay to try " Intravenous alone "
method for natural cases of equine surra. The dose used was 50 c.c. of 10
per cent solution per 1000 lb. body-weight given at intervals of 10 days.
Satisfactory cure was reported after a period of 3 weeks and no relapse oc-
curred even after 2 years in some cases under observation.
Taylor [1934] found the combined method of treatment of Naganol and
tartar emetic to be effective. The routine method of treating equine surra
consisted of a course of seven intravenous injections at intervals of 4 to 5
days in the following dosage:—
1 per cent solution of Naganol
....
1 per cent solution of tartar emetic ....
1.5 per cent solution of tartar emetic ....
1.5 per cent solution of Naganol
....
2 per cent solution of tartar emetic ....
2.5 per cent solution of tartar emetic ....
2 per cent solution of Naganol
....
100 c.c.
100 c.c.
100 c.c.
100 c.c.
100 c.c.
100 c.c.
100 c.c.
The percentage of cure of approximately 87.6 has been reported. The
period of treatment extends to about a month. On an average four and
half gm. of Naganol are required along with seven gm. of tartar emetic to
effect a complete cure. This method has been recommended as it is com¬
paratively cheap.
Pfaff [1934] carried out experiments with the use of Antimosan and
Naganol to determine their toxic, curative and prophylactic value.
The
results obtained by using Antimosan were very unsatisfactory. On the
other hand, experiments with Naganol gave encouraging results. He suggest-
ed that a single injection of 0.4 gm. Naganol per 100 lb. body-weight would
cure many cases of surra and the same dose repeated on the eighth day
would cure nearly all cases of surra. For prophylaxis the same dose should be
repeated every six weeks.
Shahi [1935-36] adopted a modified technique of four injections con-
sisting of two of 2 per cent Naganol solution at an interval of 22 days and
in between these were sandwiched two injections of 60 to 100 c.c. of 1 per cent
tartar emetic solution once a week. Cases of relapse in mules in some centres
of treatment were reported.
Serum therapy in trypanosomiasis did not show any desirable effect
and hence did not warrant any further work.
METHOD OF TREATMENT IN ASSAM
Extensive trials have been made in Assam to regulate and determine
the safe and effective dose of Naganol. The earliest attempts at treatment
with various chemotherapeutic agents are of less importance as compared
with the success that attended the standardization of the dosage of the present
routine method that has been found most suitable to the field conditions of
Assam. It was on the 5 July 1935 that an experimental attempt was made to
work out the dose of Naganol and the necessary period that should elapse
between the injections. The Director, Veterinary Department, Assam,
Rai Sahib Srish Chandra Ghose, initiated these experiments and it was under
his instruction and guidance that a satisfactory method was evolved. During