738 DISEASES AND ABNORMALITIES. 



systems of management, or giving food deficient in the necessary con- 

 stituents of the blood. Hence, he asserts, it is seen when Ewes have 

 been fed on an abundance of turnips, without a sufficient allowance of 

 hay or corn, particularly if the turnips are decaying, or have been un- 

 duly forced with artificial manures. 



It has also been remarked that it often occurs on heath lands which 

 are much exposed, and have been top-dressed with marl ; but the ap- 

 pearance of the malady only when the young creatures are at the teat, 

 rather negatives the idea that exposure has any thing to do with it. It 

 has likewise been noted, that when Ewes are fed on decaying turnips or 

 mangold wurtzel, the lambs are frequently the subjects of effusions of 

 lymph between the muscles — the effusion being arrested when corn is 

 given to the Ewes. 



Walley insists upon an altered condition of the milk as the cause of 

 the disease. '* That it is due to, and must be associated with, an altered 

 condition of the mother's milk is proved by the fact that it only attacks 

 young animals while sucking the dam ; that the Ewes coincidentally die 

 from malignant paturient fever (though it must be borne in mind that it 

 . is not necessary that the Ewe should exhibit any external symptoms of a 

 diseased condition of the blood); and that it is frequently found to disap- 

 pear on farms which have been heavily limed and drained, and also when 

 a different system of management has been adopted. Again, the general 

 post-mortem appearances bear a strong resemblance to those of distemper 

 in the dog, especially of the hepatic form of the disease ; and the enlarged 

 and softened state of the liver, where external symptoms have not been 

 manifested, points to disease of a typhoid character, brought on by the 

 imbibition of impure milk." He enumerates the exciting causes as "ex- 

 posure ; cold, damp pastures (hence the more frequent localization of the 

 disease in the joints); neglect at birth, allowing the young animals to be- 

 come covered with mud and dirt, thus preventing the dam licking them ; 

 excess of wet weather, etc." 



Roloff, as just mentioned, thinks the development of the disease is due 

 to the insufficient ingestion of calcareous salts ; and as the malady is 

 originated during intra-uterine life or the sucking period, it is evident, he 

 adds, that it is in the regime to which the dam is submitted during gesta- 

 tion, when the osseous system of the foetus is being developed, and when 

 suckling, that the cause of the disorder must be especially sought for. 

 Careful analyses have shown that the ash of the herbage or hay in the lo- 

 calities where the malady makes the largest number of victims, does not 

 contain more than six to eight per cent, of lime salts, while that of good 

 quality should have from eleven to thirteen per cent. It is also remarked 

 that this form of arthritis sometimes prevails in those places where the 

 osteoclasty of cattle is frequent ; and this coincidence, it is affirmed, 

 should indicate a common origin of the two affections — a defective sup- 

 ply of calcareous salts, and particularly of the phosphates This defi- 

 ciency is sometimes noticed when the food is relatively of a rich charac- 

 ter ; though then the amyloid and proteic constituents are in excessive 

 proportion. 



Bollinger, whose scientific and most valuable researches in compara- 

 tive pathology entitle his opinions to the greatest consideration, enter- 

 tains different views as to the origin of the malady ; and his anatomo- 

 pathological investigations in this direction are of the highest interest 

 and importance. His observations on this disorder commenced in 1869, 



