1907 Report of the Government Veterinary Bacteriologist of the Transvaal 1907 - 1908

Permanent URI for this collectionhttp://hdl.handle.net/2263/9594

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

CONTENTS

Letter of transmittal		1

PART I - INVESTIGATIONS INTO SOUTH AFRICAN DISEASES By Dr. ARNOLD THEILER, C.M.G., Government Veterinary Bacteriologist

(a) The immunity of cattle inoculated with Piroplasma mutans		2

(b)The influence of cold on ticks and Piroplasma parvum		10

(c) Further experiments with biliary fever of equines		13

(d) The inoculation of mules with polyvalent virus		24

(e) The loss of virulency of horsesickness virus in practice		50

(f) On the variability of a particular strain of horsesickness virus		57

(g) Fever reactions in horses simulating horsesickness		114

PART II - PHYSICAL-CHEMICAL INVESTIGATIONS INTO SOUTH AFRICAN DISEASES By Dr. WALTER FREI, Assistant Government Veterinary Bacteriologist

(a) Volume of blood corpuscles		127

(b) Viscosity		129

(c) Surface tension of serum		140

(d) Electric conductivity		150

(e) Comparative physical-chemical research, with special reference to horsesickness		154

(f) Horsesickness		191

(g) Piroplasmosis		210

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On the variability of a particular strain of horsesickness virus
(Pretoria: Government Printer and Stationery Office, 1909) Theiler, Arnold, Sir, 1867-1936; Transvaal Department of Agriculture
Conclusions: 1. The virus Tzaneen has in no instance been virulent for all mules injected; this virulency differs, so to say, from animal to animal; one particular animal seems to influence the virus in such a way that this virulency is either decreased or increased. 2. This reduction of virulency is by no means the result of the dose of virus or of method of injection; small and large doses, injected subcutaneously or intra-jugularly, equally fail to produce reactions. 3. This difference in virulency is either due to the virus itself or to the injected animal, but considering that animals which resisted quantities of virus of one particular type, subcutaneously or intra-jugularly, contract horse-sickness from a subsequent subcutaneous injection of a smaller quantity, it shows that it is not so much the resistance of the animal but the virulency of the virus of the given animal. 4. It is probably correct to conclude that both animal and virus must be in a certain relation to each other before a reaction can ensue.
The loss of virulency of horsesickness virus in practice
(Pretoria: Government Printer and Stationery Office, 1909) Theiler, Arnold, Sir, 1867-1936; Transvaal Department of Agriculture
Resume: The experiments prove that a virus may become inert in practice; this avirulency is due to some foreign matter, inasmuch as inert virus added to virulent sterile virus promptly produces avirulency. It is probable that this avirulency is due to the presence of some germ, but the experiments have not been carried out to the extent necessary to determine the nature of this micro-organism. Conclusions: 1. The avirulency of a virus takes place a certain time after mixing sterile to inert virus. 2. The avirulency takes place more rapidly when the mixture is kept in the incubator than when it is kept at room temperature. 3. The mixture of virulent and inert virus produces different results in injected animals according' 1"0 the method of inoculation. The same virus which proves inert after a subcutaneous injection may be virulent for an intrajugular injection. 4. The intrajugular injection of large doses of inert virus does not produce immunity. 5. It is clear that a certain virus may become inert, and therefore this fact influences the preparation and preservation of virus to be used in practice.
Electric conductivity
(Pretoria: Government Printer and Stationery Office, 1909) Frei, Walter; Transvaal Department of Agriculture
Experiments were carried out to study quantitatively the influence of various organic colloids in different concentrations on the conductivity of the same electrolyte, that is to say, the influence of albumine, globuline, gelatine, and saponine on the ions Na and OH. Albumine and globuline are colloidal components of serum wherein also both ions are present.
Letter of transmittal
(Pretoria: Government Printer and Stationery Office, 1909) Theiler, Arnold, Sir, 1867-1936; Transvaal Department of Agriculture
Comparative physical-chemical research, with special reference to horsesickness
(Pretoria: Government Printer and Stationery Office, 1909) Frei, Walter; Transvaal Department of Agriculture
Experiments were undertaken to find differences by means of various physical methods combined between normal horses, horses suffering from horse-sickness, horses immune and hyperimmune against horse-sickness and serum horses, i.e. horses from which great quantities of blood have been taken (artificial anaemia). Results: Horses suffering from horse-sickness are distinguished by the following peculiarities from normal horses (average values):- Volume of blood corpuscles and viscosity of blood are supernormal during the climax, but considerably below normality during the end of the disease and a certain time after it. Specific gravity, viscosity, and conductivity of serum are lower than normal at the climax and at the end of the attack. The differences between normal and immune horses are as follows:- The average volume of blood corpuscles is lower than normal. The specific gravity is evidently subnormal, because the average is lower, and 72 per cent. of the values of immune and hyper immune horses lay below the normal average.. The same is the case with the surface tension of serum - eight of ten values are lower than the normal average.
Surface tension of serum
(Pretoria: Government Printer and Stationery Office, 1909) Transvaal Department of Agriculture
Resume: The surface tension IS a factor of enormous biological importance, especially for the phenomena of haemo- and bacteriolysis, phagocytosis and enzyme reactions. The surface tension of serum of horses suffering from horse-sickness is subnormal. Infusion of homogeneous blood and considerable loss of blood have an influence on the surface tension of horse serum. The alkalinity of the serum guarantees a certain height and probably stability of the value of surface tension, but this latter one increases not proportionally with an increase of the hydroxylion-concentration; there is a certain optimum (perhaps two optima), and when this is surpassed the tension decreases again. The anions SO4, Cl, NO3 increase the surface tension of neutral gelatine in exactly the same the kations Na, K, Mg Ca nearly in the same order in which the capillarity of water is increased by them. The order of influence of the Na-anions N03, CI, S04 on gelatine is reversed as soon as the reaction is changed. The degree of influence of these ions is much higher in the acid than in the alkaline gelatine. The surface tension of neutral gelatine (and neutral serum) is increased by the OR and decreased by the R-ion.
Further experiments with biliary fever in equines
(Pretoria: Government Printer and Stationery Office, 1909) Theiler, Arnold, Sir, 1867-1936; Transvaal Department of Agriculture
Horses and mules were inoculated against piroplasmosis and it was found that Argentine and Transvaal horses and mules can safely be inoculated against piroplasmosis by using donkey foal blood of the fourth generation and upwards.
Volume of blood corpuscles
(Pretoria: Government Printer and Stationery Office, 1909) Frei, Walter; Transvaal Department of Agriculture
Values for the volumes of blood corpuscles of horses, donkeys and sheep are examined.
The influence of cold on ticks and Piroplasma parvum
(Pretoria: Government Printer and Stationery Office, 1909) Theiler, Arnold, Sir, 1867-1936; Transvaal Department of Agriculture
Resume: 1. A temperature of 0 C. retards the hatching of Rhipicephalus appendiculatus nymphae into adults. 2. A temperature of 0 C. does not interfere with the development of the parasite within the engorged nymphae. 3. A temperature of 0 C. does not kill the virus contained in engorged nymphae of Rhipicephalus appendiculatus. 4. Larval ticks of Rhipicephalus decoloratus die within thirty minutes when exposed to a temperature of -18 C. 5. Larval ticks of Rhipicephalus decoloratus do not die when exposed to a temperature of -18 C. for fifteen minutes. 6. Larval ticks of Rhip1:cephalus decoloratus do not die when exposed to a temperature of -5 C. for twenty-four hours. 7. The majority of larval ticks of Rhipicephalus decoloratus die when exposed to a temperature 6f -5 C. for forty-eight hours.
Horsesickness
(Pretoria: Government Printer and Stationery Office, 1909) Frei, Walter; Transvaal Department of Agriculture
Physical-chemical characteristics of horses such as body temperature, volume of erythrocytes, viscosity of blood, viscosity of serum, specific gravity of serum, conductivity of serum etc. were examined.
Viscosity
(Pretoria: Government Printer and Stationery Office, 1909) Frei, Walter; Transvaal Department of Agriculture
Viscosity of blood, defibrinated blood, serum and plasma are compared.
The inoculation of mules with polyvalent virus
(Pretoria: Government Printer and Stationery Office, 1909) Theiler, Arnold, Sir, 1867-1936; Transvaal Department of Agriculture
Conclusions: 1. Animals immunised with a polyvalent virus and tested with the same virus show reactions when subsequently retested with the identical virus. 2. When the immunity was tested with constituents of this virus, breakdowns occurred to a large extent in the first test, and even in the second test, showing that the virus, considered to be polyvalent, did not contain all the constituents which were originally mixed. The fact remains, however, that none of the tested animals died, thus showing that the immunity resulting from the CD (composite district) virus protected against any of the constituents. 3. For the purposes of the practice, where such severe tests are hardly encountered, the immunity given by this CD virus should prove sufficient.
The immunity of cattle inoculated with Piroplasma mutans
(Pretoria: Government Printer and Stationery Office, 1909) Theiler, Arnold, Sir, 1867-1936; Transvaal Department of Agriculture
CONCLUSIONS: 1. The exposure of animals immune against redwater in the low veld proved that this immunity protected against the redwater of that veld. 2. Animals immune against heartwater were protected against that disease in the low veld. 3. Animals which were only immune against redwater contracted a Piroplasma mutans infection when exposed in the low veld. 4. All the animals which were not immune against Piroplasma mutans contracted this infection when exposed in the low veld, but none died. 5. Of the two control animals which were not immune against any of the ,diseases both died; Piroplasma mutans was present ~n both cases, but the deaths were due to heartwater, and in one case complicated with redwater. 6. All the exposed animals showed reactions, due either to heartwater or to some other agency, and this reaction, in the majority of cases, caused an increase in the number of Piroplasma mutans present in the blood. 7. The animals which were immune against heartwater, Piroplasma mutans, and Piroplasma bigeminum showed a slight Piroplasma mutans infection, and also a slight reaction.
Piroplasmosis
(Pretoria: Government Printer and Stationery Office, 1909) Frei, Walter; Transvaal Department of Agriculture
RESUME. 1. Piroplasmosis of the horse is a disease with periods also pronounced by physical-chemical alterations of blood and serum. 2. The haemolysis, produced by the intra-globular parasites, has to be considered to be the cause of a great number of physical-chemical symptoms of the serum, for the latter depend in several points on the state of the blood corpuscles. 3. Volume of blood corpuscles, viscosity, and specific gravity of the blood all decrease. Never was an increase of the viscosity noticed; contrary to what is observed in horse-sickness. 4. Viscosity, specific gravity, conductivity, and surface tension of serum also decrease, the latter especially in the beginning of the disease. The osmotic pressure of serum decreases in every instance; in four cases out of six an increase precedes, and can amount even to more than 100 per cent. The specific gravity decreases in four instances and increases in two instances. 5. Physical-chemical alterations emphasise themselves by the methods in use before the temperature starts to rise (conductivity the first day, depression of freezing point, viscosity, surface tension, and specific gravity). Therefore, if we call incubation period the time between infection and the appearance of the first signs of the disease, it would be in some of our cases of piroplasmosis not more than twenty-four hours (2840, 2841); in other cases (3260, 3248, 3249), about four days; that is to say, much shorter than when only considering the appearance of fever. 6. The physical-chemical alterations of the urine are not typical and regular, like those of serum and blood; some of them are extraordinary, all show dependence on the state of the serum and demonstrate again the regulatory functions of the kidneys.
Fever reactions in horses simulating horsesickness
(Pretoria: Government Printer and Stationery Office, 1909) Theiler, Arnold, Sir, 1867-1936; Transvaal Department of Agriculture
Conclusions: The injection of two-mule Tzaneen virus protected against four-mule Tzaneen virus, but not completely against the exposure virus. The two-mule Tzaneen virus, the four-mule Tzaneen virus, and the exposure virus when injected separately or as a mixture produced reactions and an acceleration of the pulse, and no animals died. Since the two and four mule virus did not completely protect against the ephemeral fever virus, we have to conclude that these, although distinct, are to a certain extent related. Neither of the three ephemeral fever vira protected against a horse-sickness vira, and therefore it has to be concluded that there is no connection between these ephemeral fevers and horse-sickness.

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