December 30, 1897] 



NA TURE 



199 



must be pointed out that when the raw or unglycerinated 

 gall was used as the protecting medium, a certain small 

 proportion of cases contracted severe and even fatal 

 attacks of rinderpest ; though whether this was due to 

 the gall itself or to the accidental contamination with 

 virulent blood is not stated in the report, though we 

 should imagine that this latter accident might be by no 

 means uncommon. 



Finally, there is the method based on the use of the 

 "anti-bodies" found in the blood of salted cattle, i.e. 

 cattle that have suffered from a severe attack of the 

 disease, but have recovered. By injecting gradually in- 

 creasing quantities of virulent blood into such animals, 

 the anti-bodies appear in still larger proportions in the 

 blood, and can then be used either in the form of a serum 

 solution or as a defibrinated blood solution. This serum 

 may be used to confer such a degree of passive immunity 

 on the animal, that it either escapes the disease al- 

 together, or contracts it in a much modified form ; again, 

 I the serum may be used to cure an animal in which there 

 is already a rise of temperature accompanied by other 

 signs of a naturally acquired attack of rinderpest. 



All these methods have now been used at the Cape, 

 and it may be of some interest to our readers to learn 

 what is the consensus of opinion as laid down in the 

 Resolution of Conference. It is agreed " that inoculation 

 with bile, either pure (Dr. Koch's) or glycerinated (Dr. 

 Edington's), should not be adopted in any district in 

 which it has not already been commenced, as more satis- 

 factory and more permanent results are obtained from 

 the use of serum, and the latter method can be more 

 successfully applied in clean herds than in herds which 

 have been previously inoculated with bile." 



The " Conference " then arrive at the conclusion that 

 it is better not to recommend that the inoculation with 

 Koch's bile should be followed by an inoculation with 

 virulent blood on the tenth day, as formerly recommended, 

 as it is found that unless this blood inoculation is followed 

 by a decided reaction — which occurs very rarely — the 

 immunity already conferred by the bile is not increased. 

 It is recommended, however, that in the case of dairy 

 cattle which have already been inoculated with Koch's 

 bile a second bile inoculation may be made, as this will 

 confer a protection for several months, and at the same 

 time will not interfere with the secretion of milk. 



The glycerinated bile method should be followed on 

 the tenth day by the inoculation of one-tenth of a c.c. 

 of virulent blood ; and although a second blood inocu- 

 lation fourteen to seventeen days later increases the 

 active immunity in certain cases, its use has been fol- 

 lowed by considerable mortality, and the Conference, 

 while not opposing a second inoculation of blood, does 

 not recommend its universal adoption, as it is attended 

 with considerable risk. 



There appears to be a decided opinion that serum, 

 when properly prepared, is superior to, and much 

 more convenient for use than defibrinated blood, and 

 its use is strongly recommended in preference to the 

 latter when it can be obtained, though it is also recom- 

 mended that a certain number of fortified salted cattle 

 — i.e. immunised cattle — be sent to districts far removed 

 from centres where serum is prepared, in order that de- 

 fibrinated blood may be prepared in cases of sudden 

 emergency. 



It seems to be the general experience (as in other 

 diseases in which the serum treatment is used) that in 

 healthy herds the use of serum alone does not confer 

 a very permanent immunity ; it is therefore considered 

 necessary, in infected districts, to infect healthy animals 

 with rinderpest, and keep the attacks under control by 

 means of the serum. This may be most safely and 

 satisfactorily accomplished by injecting virulent blood 



Isubcutaneously on one side of the animal, and serum 

 on the other. If necessary, i.e. if the disease takes 



too active a form, a fresh dose of serum will usually 

 enable the animal to pull through the attack. For 

 all practical purposes, however, it has been found that 

 clean herds, in which there is no disease already, 

 should not be inoculated with serum until the disease 

 makes its appearance amongst them, or in their im- 

 mediate neighbourhood. The whole of the animals 

 should then be injected, after which, or simultaneously, 

 they may be injected with virulent blood, or be kept in 

 close continuous association with infected animals by 

 kraaling them together every night. In this way the 

 animals become salted or protected ; under these con- 

 ditions the immunity produced is active and of long 

 duration, as opposed to the temporary and passive 

 immunity that is conferred by serum when used alone, 

 and perhaps also by bile. Where bile has already 

 been inoculated, it is no use to inject serum and 

 then virulent blood ; for, as already mentioned, the 

 immunity conferred by the bile varies very greatly in 

 degree in different cases. Where such bile inoculation 

 has been resorted to, the most satisfactory course for the 

 owner to pursue is to keep a supply of serum by him and 

 inject all cattle as soon as they are observed to be ill, 

 or as soon as the thermometer indicates a rise of tempera- 

 ture. Where serum cannot be obtained, as already 

 mentioned, the blood from salted cattle may be used. 

 These salted cattle are usually fortified by injections of 

 virulent blood, commencing with lo c.c, and then going 

 to 20, 50 and, lastly, loo c.c. at intervals of ten days. 

 Either serum or blood is injected in quantities of loo or 

 200 c.c. into the animals suffering from the disease. This 

 injection may be made subcutaneously, and not into the 

 muscles, either behind the shoulder or into the dewlap. 



It is, perhaps, too early to be dogmatic on the question 

 of the best method of treating cattle for the prevention and 

 cure of rinderpest, but when the exceedingly fatal nature 

 of the disease is borne in mind, and when it is remem- 

 bered that the disease is so markedly infective and fatal 

 that whole herds are practically exterminated when once 

 the disease is introduced (the objections that are brought 

 forward against inoculation against anthrax, that the 

 percentage mortality from inoculation is almost or quite 

 as great as the percentage mortality from the disease 

 itself not holding good in this case), it is not to be 

 wondered at that the South African farmers received with 

 enthusiasm any method which would preserve to them 

 even a large percentage of their cattle, and that many of 

 them were quite willing to run the risk of introducing 

 rinderpest through the bile inoculation if they could only 

 be sure that some 60 or 70 per cent, of the so infected 

 animals would recover, and would then be protected to 

 a certain degree against future attacks. 



As Koch's bile method complied with such conditions 

 it was undoubtedly a marked step forward, whilst it also 

 made it possible to obtain salted cattle with which serum 

 experiments might afterwards be carried out. 



These serum experiments— showing that in serum the 

 veterinary surgeon has in his hands a weapon by using 

 which he is able to control the course, even of a severe 

 attack of rinderpest— have given the farmers confidence 

 enough to make them actually anxious to produce the 

 disease under such conditions that they may keep it 

 under control, and so salt their cattle artificially ; thus 

 rendering them immune for a considerable period against 

 infection, even of the most virulent character. 



With the vast agricultural and cattle-breeding interest 

 at stake, we may anticipate that Koch's earlier experi- 

 ments will, in the very near future, be improved upon, 

 that South African cattle raisers and dealers will in the 

 long run be enormously benefited, and that a source of 

 wealth, which until a very short time ago was threatened 

 with almost immediate extinction, will continue to be one 

 of the principal resources of a great and flourishing 

 colony. 



