1906 Report of the Government Veterinary Bacteriologist of the Transvaal 1906 - 1907

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Contentes Pages: Onderstepoort Journal of Veterinary Research, Vol ??, 19??

CONTENTS

Letter of transmittal		1

Comments on the various articles in section 5		1


MISCELLANEOUS INVESTIGATIONS:

(a) Gouw-ziekte		21

(b) Stiff sickness, or three days' sickness		22

(c) Internal parasites		23


ROUTINE SECTION:

(a) Microscopical and pathological anatomical examinations		23

(b) Returns relating to calf vaccine lymph		34

(c) Returns of issues of horsesickness serum		35

(d) Returns of issues of quarter evil vaccine (sponsziekte)		35

(e) Returns of issues of bluetongue vaccine		35

(f) Publications, staff, etc.		36

(g) Administration report		37


RESEARCH SECTION:

(a) Further notes on Piroplasma mutans : a new species of Piroplasma in South African cattle		45

(b) Experiments with English and South African redwater		62

(c) Transmission experiments with East Coast fever		70

(d) Result of horsesickness inoculation in practice during 1906-1907		85

(e) Further notes on immunity in horsesickness		89

(f) Immunisation of mules with inadequate and adequate serum and virus, and the immunity obtained therefrom		162

(g) Inoculation of mules with polyvalent virus and serum		192

(h) Continuation of experiments for inoculation against equine piroplasmosis (biliary fever)		214

(i) Inoculation of sheep against bluetongue and the results in practice		263

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Further notes on immunity in horsesickness
(Pretoria: Government Printing and Stationery Office, 1908) Theiler, Arnold, Sir, 1867-1936; Transvaal Department of Agriculture
The full history of the treatment accorded to each animal is apparent from the tables. Conclusion : These experiments show conclusively that when a horse or mule is inoculated with a certain strain of virus, the animal, as a rule, is immune against that particular strain, but when the animal is tested or hyperimmunised at a later date with virus of a different strain, reactions and deaths are noted, thus proving that the immunity afforded by the first inoculation is in no way complete. The last table shows the percentage of reactions (including doubtful reaction and dikkop) and deaths amongst the inoculated mules and horses included in the previous experiments. This table is compiled according to the number of the test (1st, 2nd, 3rd, etc.), and irrespective of the virus with which they were immunised or tested, and will serve as an indication of the results to be expected in practice. It is particularly instructive as demonstrating the difference between the immunity in horses and mules when obtained under the same conditions.
Inoculation of mules with polyvalent virus and serum
(Pretoria: Government Printing and Stationery Office, 1908) Theiler, Arnold, Sir, 1867-1936; Transvaal Department of Agriculture
Conclusion:-The immunisation against a polyvalent virus with an adequate serum produces immunity which protects against any of its constituents. The immunity is strong enough to prevent a reaction in the majority of cases, and strong enough to pass the reacting animals through a mild disease. Compared with the results obtained by the injection of a mixture of sera and their adequate vira, the immunity of the polyvalent virus and serum protects better against the constituents of the said polyvalent virus. I must state here that the reactions noted after the injection may not always be due to the injection, but may be of a coincidental nature, or the reaction may not necessarily be a horse-sickness reaction. At the same time, we have no other means of controlling horse-sickness reactions except by the thermometer, inasmuch as slight reactions are not accompanied with characteristic symptoms. For practical purposes, however, I consider that the immunity obtained by a polyvalent virus will, in practice, protect better than that obtained by an individual strain of virus.
Result of horsesickness inoculation in practice during 1906-1907
(Pretoria: Government Printing and Stationery Office, 1908) Theiler, Arnold, Sir, 1867-1936; Transvaal Department of Agriculture
Inoculation of sheep against bluetongue and the results in practice
(Pretoria: Government Printing and Stationery Office, 1908) Theiler, Arnold, Sir, 1867-1936; Transvaal Department of Agriculture
The results of the experiments show very clearly the advantage that vaccinated sheep have over susceptible animals.
Transmission experiments with East Coast fever
(Pretoria: Government Printng and Stationery Office, 1908) Theiler, Arnold, Sir, 1867-1936; Transvaal Department of Agriculture
Conclusions: Rhipicephalus decoloratus and amblyomma hebraeum must not be considered as hosts of piroplasma parvum. Rhipicephalus appendiculatus, evertsi, capensis, simus, and, according to Lounsbury, also nitens, must be considered to be hosts of piroplasma parvum. It may safely be concluded that piroplasma parvum in its life cycle of development does not pass through the egg, and finally it is evident that immune animals do not carry the infection.
Comments on the various articles in section 5
(Pretoria: Government Printing and Stationery Office, 1908) Theiler, Arnold, Sir, 1867-1936; Transvaal Department of Agriculture; Orpen, J.M.
Further notes on Piroplasma mutans : a new species of Piroplasma in South African cattle
(Pretoria: Government Printing and Stationery Office, 1908) Theiler, Arnold, Sir, 1867-1936
Experiment 1 was the infection of animals known to be immune against redwater with piroplasma mutans. Experiment 2 was heifers infected with blue larval ticks in thew first instance, causing a pure infection of piroplasme bigeminum, and subsequently injected with blood containing piroplasma mutans.Experiment 3 was done with susceptible heifers injected(1)with piroplasma bigeminum exclusively, (2) infested with larval blue ticks feeding on animals containing piroplasma bigeminum and piroplasma mutans in their blod, and (3) injected with blood containing piroplasma bigeminum and piroplasma mutans. Experiment 4 was to prove that the injection of blood of an animal immune to redwater which contracted the disease from ticks, is not followed by the appearance of piroplasma mutans. Experiment 5 was with spontaneous cases of piroplasma mutans originating in the Cape Colony. Experiment 6 was with spontaneous cases of piroplasma mutans originating in the Transvaal. Experiment 7 was to show that blood containing piroplasma bigeminum and piroplasma mutans when injected into cattle susceptible to ordinary redwater does not always cause the former parasite to appear.
Routine section
(Pretoria: Government Printing and Stationery Office, 1908) Theiler, Arnold, Sir, 1867-1936; Transvaal Department of Agriculture; Parkes, E.B.H.
Continuation of experiments for inoculation against equine piroplasmosis (biliary fever)
(Pretoria : Government Printing and Stationery Office, 1908) Theiler, Arnold, Sir, 1867-1936; Transvaal Department of Agriculture
Conclusions: (1) The inoculation of animals with horse foal blood of 1st, 2nd and 3rd generations caused a mortality of 7 out of 186, or 4 per cent. (2) The inoculation of animals with horse foal blood of 4th, 5th, 6th, 7th and 8th generations caused a mortality of 1 in 16, or 6 per cent. (3) The inoculation of animals with donkey foal blood of 2nd to 6th generation caused no mortality amongst 25 animals. (4) The reactions caused by injection of horse foal blood were more severe than those given by injection of donkey foal blood. (5) No cases of relapses after discharge have occurred, proving that the immunity given by the injection of donkey foal blood is as good as that afforded by horse foal blood. (6) For further immunisation purposes, therefore, I recommend the passing of blood originating from a natural infection of a donkey with piroplasma equi through donkey foals, and to use 1 c.c. blood of that obtained from the 4th generation and upwards, bearing in mind the precautionary measures mentioned above. (7) Finally, all foals kept for tapping purposes, and used in connection with the inoculation, must be kept free from ticks. This precaution has been carried out at this Laboratory with all foals used in the experiments, and it stands to reason that a reinfection bv means of ticks would increase the virulency of the blood which is to be used as vaccine.
Immunisation of mules with inadequate and adequate serum and virus, and the immunity obtained therefrom
(Pretoria: Government Printing and Stationery Office, 1908) Theiler, Arnold, Sir, 1867-1936; Transvaal Department of Agriculture
Conclusions: l. The simultaneous injection of serum 0 and adequate virus resulted in typical horse-sickness reactions, and the immunity obtained therefrom prevented a reaction when the adequate virus is subsequently injected. 2. The immunity obtained by a reaction after injection of serum O and virus 0 (adequate serum and virus) does not prevent a reaction due to a subsequent inoculation of virus of a different strain (Tzaneen and Bulawayo). 3. The simultaneous injection of serum 0 and virus Tzaneen (inadequate serum) is succeeded hy reactions which proved not to be more fatal to animals than that due to virus 0 (adequate serum). 4. The immunity obtained by this reaction was in no way complete. It did not prevent a reaction either due to a subsequent inoculation of a different strain (0 or Bulawayo), nor did it prevent reactions when the same strain of Tzaneen virus of a later generation was utilised. 5. The fact that a reaction was noted due to the subsequent inoculation of virus in an animal immunised with the same strain of virus can he explained either by accepting that the test virus, being of a higher generation and derived from horses, is of a greater virulency, or that the virus Tzaneen is already of a complex nature containing certain constituents of the 0 virus which are deviated by the 0 serum and accordingly during the immunisation leave no impression on the system of the animal. A subsequent inoculation of the same strain would then not meet the corresponding antibodies and a reaction would result. 6. In some of the animals a single injection of virus, together with adequate or nadequate serum, produced complete immunity against subsequent inoculations, hence a factor jn the animal has also something to do with the creation of immunity. 7. In the foregoing experiments it has been noted that a virus can attenuate and completely lose its virulency. 8. Virus T of the 12th generation has increased enormously in virulency, which shows itself in the immunisation and in the tests.
Experiments with English and South African redwater
(Pretoria : Government Printing and Stationery Office, 1908) Theiler, Arnold, Sir, 1867-1936; Transvaal Department of Agriculture
Conclusions: It would be seen from these notes that of four animals inoculated with English redwater, two failed to react or to show piroplasms, and in the other two instances a reaction ensued, accompanied with the appearance of piroplasms. Therefore it is safe to say that English redwater is not always inoculable, and differs in this respect from South African redwater. I do not feel justified in drawing any conclusions from the results of the injection of heifers 400, 418, 421 and 422 with blood of English heifer No. 428, for, as will be seen from Experiment 1, "A," this heifer did not appear to contract the infection in England, as no piroplasms were seen, due to an inoculation of English redwater blood, and the reaction was atypical. I therefore consider that the failure of heifer 428 to contract English redwater from the injection of virulent blood is another point in favour of my contention that English redwater is not always inoculable. The results obtained from the other five heifers, however, seem to be conclusive, as heifer 430 was certainly infected with English redwater.Therefore English redwater was not inoculable in our five South African heifers, and accordingly when tested they all contracted ordinary redwater, proving that they had not acquired any immunity against South African redwater.
Miscellaneous Investigations: gouw-ziekte; stiff sickness, or three days' sickness; internal parasites
(Pretoria : Government Printer and Stationery Office, 1908) Theiler, Arnold, Sir, 1867-1936; Transvaal Department of Agriculture
Letter of transmittal
(Pretoria : Government Printing and Stationery Office, 1908) Theiler, Arnold, Sir, 1867-1936

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