16 DISEASES OF SWINE AND OTHER ANIMALS. 



presumption tliat other genera of the same family may also contract tbe 

 disease, and by virtue of an even closer relation to the pigs, may succeed 

 in conveying the malady to distant herds. The rat is suggested as being 

 almost ubiquitous in piggeries, and more likely than any other rodent 

 to contract and transmit the disease to distant farms. In order to test 

 its susceptibility to the poison, Dr. LaAV inoculated a rat with the ^drus 

 from a sick pig, but unfortunately the subject died on the second day 

 thereafter. The body showed slight suspicious lesions, such as congested 

 lungs with considerable interlobular exudation, congested small intes- 

 tines, dried-up contents of the large intestines, and sanguinous discolor- 

 ation of the tail from the seat of inoculation to the tip. With the fresh 

 congested small intestine of the rat he inoculated one pig, and with the 

 frozen intestine one day later he inoculated a second. The first showed 

 no rise of temperature, loss of appetite, or digestive disorder ; but on 

 the sixth day i)ink and violet eruptions, the size of a pin's head and up- 

 wards, ai^peared on the teats and belly -, and on the tenth day there was 

 a manifest enlargement of the inguinal glands. In the second pig in- 

 oculated, the symptoms were too obscure to be of any real value. Dr. 

 Law wiU continue his experiments with this rodent. 



In addition to the above, Dr. Law experimented on two sheep of dif- 

 ferent ages, an adult merino wether and a cross-breed lamb, and in both 

 cases succeeded in transmitting the disease. With the mucus from the 

 anus of the wether he inoculated a healthy pig, which showed a slight 

 elevation of temperature for five days, but without any other marked 

 symptoms of illness. Eleven days later it was reinoculated with scab 

 from the ear of the lamb, and again thi'ee days later with anal mucus 

 from the sheep. The day preceding the last inoculation it was noticed 

 that the inguinal glands were much enlarged, and in six days thereafter 

 the temperature was elevated and pui"ple spots appeared on the belly. 

 At the time that Dr. Law closed his report this fever had lasted but a 

 few days, but he regai-ds the symptoms, taken in connection mth the 

 violent rash and the enlarged Ijonphatic glands, as satisfactory evidence 

 of the presence of the disease. It can, therefore, be affirmed of the 

 sheep as of the rabbit, that not only is it subject to this disease, but 

 that it can multiply the poison in its system and transmit it back to the 



pig- 



Among the later experiments by Dr. Law was one inaugurated with 

 the view of testing the vitality of fi'ozen products of the disease. This 

 poiut was briefly alluded to above, but it« importance ■\^'Oldd seem to 

 call for fiu'ther attention. In two cases healthy pigs were inoculated 

 with virulent products which had been frozen hard for one aud two days 

 respectively. In l)oth instances the resulting disease was of a very vio- 

 lent type, aud would have proved fatal had it been left to run its course. 

 The freezing had failed to impair the virulence of the product; on the 

 contrary, it had only sealed it up to be opened and given free course on the 

 recurrence of warm weather. Once irozen no change could take place 



