sively in Germany and elsewhere. In 1897 Sobernheim announced that he had succeeded in immunizing 8,000 sheep, among which number only eight died of anthrax. The method has been tried in the treatment of anthrax in cattle, horses, and other animals. Jaeger in his experiments showed that the therapeutic action of the serum obtained by Sobernheim depends almost entirely upon the method of inoculation. Subcutaneous inoculation, even in large doses, merely served to check the progress of the disease for a few days. Intravenous injection of serum, however, was almost always sufficient to save the life of even badly affected animals, and this method was found to be quite harmless. In experiments carried out by Strebel it was found that considerable success could be expected in the prevention of the disease by the adoption of direct antisepsis and the use of vaccines. Carbolic acid was tested in intravenous injections without satisfactory results. Gilruth in a long series of experiments found that guinea pigs, rabbits, and sheep may exhibit a complete resistance to inoculation with large doses of virulent anthrax bacilli if these organisms are mixed with a larger quantity of another organism which is not pathogenic to the animals in question. The anthrax bacillus must be mixed with the other organism, for if they are injected simultaneously in different parts of the body no resistance is brought about. The immunity thus produced is somewhat temporary. The best results were obtained when Gaertner's bacillus was mixed with the anthrax bacillus. The same method was later found to be applicable to cattle, a considerable number of which were successfully treated in this way." In later experiments of the same author, however, guinea pigs did not appear to display any definite resistance to anthrax bacillus when treated by this method. A thorough knowledge of the exact conditions under which spore formation takes place in the anthrax bacillus is of great importance in combating the disease. Klette concluded from his experiments along this line that the formation of spores in the anthrax bacillus is not dependent upon the presence of oxygen. Anthrax bacilli were found to form spores abundantly in an atmosphere of nitrogen, but not in one of hydrogen. Weil found that when material containing anthrax spores is subjected to favorable conditions for germination the majority of the spores germinate within a fairly constant period. It was impossible, however, to determine a time at which no spores were present in a material, and it appears impossible, therefore, to free such material from spores by the method of fractional steriliza a Schweiz. Arch. Tierh., 45 (1903), No. 3, pp. 105–113. © Ztschr. Hyg. u. Infectionskrank., 35 (1900), No. 3, pp. 420–438. 4 Arch, Hyg., 39 (1901), No. 3, pp. 205-229, a tion. New spores are always formed before all of the old spores have germinated. The germination of the greater number of anthrax spores took place, as a rule, after eight, sixteen, and seventy hours at temperatures of 37°, 24°, and 18° C., respectively. The germination of anthrax spores was strongly influenced by weak solutions of various chemical reagents. A brief exposure to 1 per cent chloroform, 1.5 per cent carbolic acid, or a 1 per cent solution of formalin destroyed all of the spores. Eijkman found that live steam under low pressure was more effective in destroying anthrax spores than was boiling water. The explanation of this difference in the effect of live steam and boiling water is believed to be found in the fact that the boiling point of water is raised by the presence of soluble materials, such as salt and sugar, while steam is not thereby influenced. The disinfection of the skins of animals affected with anthrax is an important problem of sanitation. Lignières experimented with a number of antiseptic substances, such as crude carbolic acid, lysol, cresol, creolin, etc. Solutions of crude carbolic acid and 5 per cent solutions of the coal-tar products were sufficient to destroy the anthrax bacillus, but not the spores, when the skins were dipped in these solutions for a period of fifteen minutes. Live steam with which the fumes of formalin are mixed has been found to be very efficient in disinfecting skins. Many outbreaks of anthrax are due to eating infected food. Among such material oats have often been found to be infected. In experiments to determine the best method of destroying anthrax spores on oats it was found by Jaeger that a dry heat of 180° to 200° C. for a few minutes was required to destroy these spores. For this purpose an apparatus such as commercially used for desiccating potatoes may be used. In experiments by the same author it was found that a temperature of 180° C. for a period of twelve minutes was sufficient to destroy anthrax spores in a layer of oats 2 centimeters deep. The oats, however, were considerably roasted by subjection to this temperature and were therefore greatly reduced in market value. By the use of Venuleth's apparatus it was found possible to subject the oats to a sufficiently high temperature to destroy the anthrax spores within twelve minutes without roasting the oats. The color of the oats was slightly darkened, but they were still marketable, and their nutritive value was not affected. In experiments with anthrax spores Selter found that glycerin and grape sugar in 5 per cent and 2 per cent solutions, respectively, exercise a direct influence upon the development of spores. Nonspore-bearing с a Centbl. Bakt. u. Par., 1. Abt., Orig., 33 (1903), No. 7, pp. 567, 568. Rev. Gén. Méd. Vét., 1 (1903), No. 5, pp. 249–255. Monatsh. Prakt. Tierh., 16 (1904), No. 4-5, pp. 232–235. & Centbl. Bakt. u. Par., 1. Abt., Orig., 37 (1904), Nos. 2, pp. 186-193; 3, pp. 381-389. races of anthrax bacilli were readily obtained by repeated transfers on culture media containing glycerin. Considerable importance has been laid upon the variation of the susceptibility of different races of sheep to anthrax. Martinet carried out experiments along this line, during which he selected purebred merinos, merino crosses, and lambs from crosses of the second generation. Three of the four animals thus inoculated died of anthrax, but the power of resistance varied and indicated that this power is in inverse proportion to the amount of merino blood present in the animal. This author recommends the crossing of pure merinos with some other race in localities where anthrax is liable to cause losses. TEXAS FEVER. Following upon the investigations of the Bureau of Animal Industry and experiment stations of this country foreign veterinarians have prosecuted studies on various phases of the Texas-fever problem. The disease has been identified in various countries, but is known under different names. In Argentina it is called tristeza; in Germany, hemoglobinuria; in Australia and South Africa, redwater or tick fever. It is generally admitted by investigators that the disease in all these countries is due to the same blood parasite, and that this parasite is carried from diseased or recovered animals to susceptible animals by means of ticks. Almost the only prominent investigator who doubts the agency of ticks in the transmission of the disease is Mégnin. This author, in a recent article, argues at considerable length that the agency of ticks in transmitting Texas fever has not been proved, and contends that, in order to demonstrate this point, it is necessary to find the pathogenic organism of Texas fever in the adult ticks, eggs, larvæ, and nymphs. Bey," in studying cases of Texas fever in Egypt, observed that during the first two hours after death the temperature of the carcass sometimes rose above 44° C. This post-mortem elevation of temperature is not thoroughly understood, but is a phenomenon comparable with similar occurrences in cases of Asiatic cholera in man. The German imperial health office made an extensive study of Texas fever or hemoglobinuria in Germany. It was found that, as a rule, the period of incubation of the disease in Germany is about fourteen days. In experiments carried out under the auspices of the health office it was found possible to maintain the blood parasite of the disease in serum containing hemoglobin. In some instances the a Jour. Anat. et Physiol. [Paris], 40 (1904), No. 6, pp. 569–589. blood parasite preserved in this manner remained virulent for a period of forty-two days. The parasite of the disease remained alive only for a short time in the muscles. As a result of the investigations by the imperial health office it is recommended that the material used in vaccination against Texas fever be obtained in a sterile condition, defibrinated, and preserved in an ice chest. It is further urged that it should be taken from animals only after fifty days following upon recovery from the disease. Attention is called to the desirability of making the preventive inoculation from four to six weeks before the animals are turned upon pasture and that it be given by means of the subcutaneous method in doses of 5 cubic centimeters. A new method of treating Texas fever has been suggested by Evers. This author found, in making post-mortem examinations of cattle dead of Texas fever, that the observed alterations of various organs were to be ascribed to the destruction of hemoglobin, the coloring matter of the blood. The pathological symptoms were found to disappear as soon as the normal quantity of hemoglobin was restored. Evers therefore undertook experiments for the purpose of testing the effect of the artificial introduction of hemoglobin into cattle affected with Texas fever. For this purpose pure hemoglobin was produced and was prepared in tablets weighing 2 grams each. In all about forty-three cattle were treated in this manner, and of this number forty-one recovered completely. The hemoglobin was dissolved in physiological salt solution in the proportion of 1 to 50 during the first experiment, but later the percentage of hemoglobin was considerably increased. The hemoglobin was injected by the hypodermic method. Animals submitted to this treatment recovered rapidly, usually within from five to eight days. Within recent years the existence of an extremely virulent form. of hemoglobinuria has been recognized in South Africa. This disease has been extensively studied by Koch, Theiler, Stockman, Gray, and others. At first the disease was believed to be identical with Texas fever, but merely of a more virulent form. Later, however, Koch called attention to certain striking differences between the African coast fever and true Texas fever. The disease is now recógnized as distinct from Texas fever and is known by various names, such as African coast fever, Rhodesian redwater, East coast fever, tropical bovine pyroplasmosis, etc. It has been shown by extensive investigations in the English South African colonies that African coast fever is transmitted by two species of ticks, known as Rhipice a Berlin. Tierärztl. Wehnschr., 1903, No. 52, pp. 793-797. phalus appendiculatus and R. simus. Koch carried on a long series of experiments in developing a method of vaccination against this disease and believed that he had perfected such a method. Recent experiments by Theiler," Stockman, and others have thrown serious doubt upon the value of this method. Koch found that African coast fever could not be communicated in an acute form to susceptible animals by inoculation with blood drawn from either sick or recovered animals. In this respect the disease differs essentially from Texas fever. Repeated inoculations with blood taken from sick or recovered animals produced a slight effect, however, and ultimately specimens of the parasitic organism were found in the blood of animals thus treated. In his third report Koch recommended subcutaneous inoculation of susceptible animals with fresh defibrinated blood taken from recovered animals. This inoculation was to be repeated once a week for four weeks, then once every other week for two months, and afterwards once a month. Koch modified this line of treatment to the extent of recommending regular fortnightly inoculations in smaller doses for a period of four or five months. Doctor Koch believed that in a considerable percentage of cases immunity was thus produced. Gray, however, reports that this method was carried out strictly in accordance with recommendations on over 3,700 head of cattle, in which it was found that the percentage of mortality in treated animals was no less than in those which received no treatment. It is argued, therefore, that the failure of Koch's method leaves no means of combating the disease other than those which previous experience had suggested, viz, the suspension of transportation of cattle so far as possible, fencing, and systematic dipping for a period of at least two years, in addition to the complete exclusion of all cattle from infected areas for a period of at least fifteen months. In experiments reported by Theiler unsatisfactory results were obtained from dipping and spraying experiments in which arsenical dips were used with or without the addition of izal and other substances. It appears that infection persists in a given locality for from fifteen to eighteen months. In Koch's study of the disease it was found that there are certain constant differences between it and Texas fever. In African coast fever the red blood corpuscles are more abundantly infected with the blood parasite, but the destruction of blood corpuscles is very slight as compared with that which takes place in cases of Texas fever. In African coast fever also there are observed prominent lesions in certain organs which indicate that the parasites accumulate in those a Agr. Jour. Cape Good Hope, 24 (1904), No. 5, pp. 549–560. Jour. Comp. Path. and Ther., 17 (1904), No. 3, pp. 193–203. |