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THE FARMER'S MAGAZINE. 



seen diuiug life, or after death, 2nd, The variation in point 

 of number in similar casea of disease — sheep having died 

 from rot with a dozen flukes in the liver, while in other cases 

 hundieda are found. 3rd, Their presence is not necessary to 

 the production of the changes observed. This position — of 

 immense importance in the evidence — we had some years ago 

 ample opportunity of verifying. A number of Southdown 

 ewes were browght from a low and damp situation to the 

 College Farm on the Cotswolds. Shortly after their arrival the 

 symptoms of rot presented themselves : some of the animals 

 died in a month or two; some lingered on through the lamb- 

 ing season ; some were treated at the hospital ; but eventually 

 the whole number died at various times. All were submitted 

 to a ^04^ mortem examination, and in no instance were flukes 

 found, notwithstanding all the other signs of rot were well 

 defined. We do not care to contend merely for the applica- 

 tion of the term " rot" to these cases ; we quote them as 

 proofs of the statement we have just made to the effect that 

 the various morbid changes characteristic of the disease may 

 occur unconnected with " flukes." 4th, They are never found 

 in large numbers, excepting in the advanced stages of the dis- 

 ease. If in the commencement they existed in abundance, 

 there would be a presumption in favour of their having some 

 influence in the production of the subsequent changes. In- 

 deed, a large number of these animals could not exist in the 

 biliary canals without interfering with the functions of the 

 organ ; but as they have not been found to precede, but 

 rather to follow the disease, the presumption is in favour of 

 their being to a greater extent the result of the derangement 

 rather than its cause. 



lu fine, the weight of evidence seems to us so decidedly 

 against the popular conviction, that we cannot consistently 

 accept it. Allowing full force to the sole argument in favour 

 of the belief, viz., admitting that flukes are invariably present 

 in rot, it is not logical to conclude that therefore they are 

 causes rather than effects — the mere fact of their existence 

 being equally in favour of either presumption. In support of 

 the opinion that flukes are not the essential causes of rot, the 

 arguments may be concisely stated : 1st, Flukes do not occur 

 in large numbers until the disease has made some progress. 

 2nd, The number is not invariably proportioned to the extent 

 of the morbid changes. 3rd, Exactly similar, even identical, 

 symptoms during life and post mortem appearances have been 

 found to exist unassociated with the presence of these para- 

 sites. 4th, Flukes are found in the liver not only of the 

 sheep, but also in other animals, without the concurrence of 

 any symptoms of rot. From the whole evidence we draw the 

 following conclusions : 



1. The fluke (Jjistoma Jiepaticmn), while yet in one of its 

 transition forms, is introduced into the organism of the higher 

 animals. 2. In a healthy condition of the system only a few 

 of the larvc? reach their full development. 3. When the 

 animal infested is placed under circumstances which occasion 

 derangement of the secretive functions, particularly of the 

 liver, the " distoma brood" is favourably situated for attaining 

 its final and mature state, and, by excessive accumulation, 

 assists in the production of the organic changes associated 

 with the advanced stages of rot. 



Causes Acting from WitJiout. — If it can be shown 

 that certain external circumstances are capable of acting upon 

 the system in such a way as to produce the changes observed, 

 we presume no necessity will exist for assuming other cauaes 

 whose action is not so capable of demonstration. With the 

 view of discussing the question how far these external con- 

 ditions are likely to be concerned, we select one of the two 

 conclusions at which we arrived after criticising the general 

 evidence. " Rot occurs in moist situations after a warm rain 

 has caused a luxuriant [irowllt of herhciQe." In order to ex- 

 plain the effects of food thus rapidly developed, it has been 

 assumed that the saccharine and starchy matters are excessive 

 in plants so developed. The speculation is plausible, and in 

 a measure explains the ccourreuce of the changes observed in 

 rot; but to assume what chemistry can so easily prove seems 

 to us unjustifiable, particularly when so much depends on the 

 truth of the position. An extensive investigation, micro- 

 scopic and chemical, upon the herbage and soil of meadows 

 where rot occurs, is [needed. In its absence, however, my 

 colleague. Dr. Voclcker, furnishes me with the following im- 

 portant facts as the results of his own observations : " Plants 

 rapidly developed — for instance, swedes grown for exhibition 

 under the stimulating action of manures, also the herbage of 



water-meadows — contain one-half less of solid matter than 

 those more naturally produced ; so that the assertion that 

 there is more sugar or starch is at once negatived." The pre- 

 sence of a large amount of nitrogen has led to the belief that 

 such plants are highly nutritious •, but Dr. Voe'cker finds a 

 considerable quantity of this to exist in a peculiar half- 

 elaborated condition, or, as he expresses it, " something 

 between an organic and inorganic compound." Albumen and 

 caseine are deficient, as also are starch and sugar; much of 

 the nitrogen exists in the form of ammoniacal salts, and there 

 is also a much larger percentage of water. Such food is evi- 

 dently unfit for alimentation, with its excess of fluid and its 

 deficiency of flesh-and-fat-forming principles, not to speak of 

 the highly-stimulating ammoniacal compounds that are 

 among its constituents. Thus, so far as chemistry has inves- 

 tigated, we find just grounds for the statement that, in the 

 plants of those localities where rot is produced, there is suffi- 

 cient to account for the symptoms and post mortem appear- 

 ances of the disease. The sudden increase in the animal's 

 bulk having no reference to healthy nutrition, we may ascribe 

 to the primarily stimulant effects of the diet upon the liver 

 and to the excess of water ; a large quantity of bile we have 

 already shown leads to the absorption of fatty matters. The 

 continued consumption of the food will naturally soon induce 

 derangement that may be irremediable, even although the 

 pasture be changed. How large a quantity of this food is 

 suflicient in different instances to establish an alteration in the 

 function of the liver to the extent of producing rot it is im- 

 possible to say, but we have declined to accept that part of the 

 evidence offered us upon the occurrence of the disease from a 

 remarkably short continuance of the causes — to wit, a single 

 feed of objectionable herbage. la our remarks upon the func- 

 tion of the liver and upon the pathology of rot we endea- 

 voured, under the disadvantageous necessity of a familiar de- 

 scription, to explain how the derangement of the organ would 

 be followed by the changes found in the disease. Under the 

 head of " Causation " we considered the influence of the fluke, 

 and, for reasons then given, were compelled by the nature of 

 our evidence to exclude it from any primary share in the pro- 

 duction of the disease. Subsequently passing to an examina- 

 tion of the food produced by the localities where the affection 

 is common, we found reason to conclude that plants under 

 such circumstances are deficient in some of their moat impor- 

 tant constituents, and that altogether they furnish the condi- 

 tions requisite for the production of such changes in the func- 

 tions and structures as have been invariably observed in the 

 disease of rot. We are permitted to infer, therefore, that 

 Ihc priinanj and cssciilinl r((>i.-.(' cj' rot is the roitsitmji/uni '/./" 

 food (jrow)i under eirciini'ihdiccs irjtich prevent its natural and 

 health!/ development, modify its composition, and virtually 

 render it poisonous to the animal system. 



Treatment of Rot. 



Our previous inquiries having made us familiar with the 

 causes and characteristics of the disease, we experienced no 

 difficulty in deciding upon the appropriate treatment. Never- 

 theless it by no means follows that a correct system of medi- 

 cine should command uniformly successful results ; on the 

 contrary, a number of modifying agencies may combine to 

 render such a system abortive. In the case of the sheep, we 

 have to contend against the naturally defective tone produced 

 by a highly artificial and inconsistent plan of breeding and 

 feeding ; t'le diminished tonicity renders the animal an easy 

 victim to nearly every form of disease, and lessens the chances 

 in favour of medicinal treatment. With the economic con- 

 siderations that may complicate the question of treatment we 

 have nothing to do. We are to assume that the cure of the 

 disease is a matter of some moment, and accordingly proceed 

 to suggest a plan of procedure founded upon our knowledge of 

 the causes aud nature of the disease. First, to remove the 

 animals from the locality where the malady is produced is of 

 course an indispensable step ; a high, or rather perfectly dry 

 situation, where the herbage is healthy and fully grown, is de- 

 sirable ; where the appetite is good, a full allowance of food 

 may be given. Good hay, oats, linseed, and beans, properly 

 crushed, are found practically to be most useful. Medicinal 

 treatment should be directed to the support of the respiratory 

 functions, the restoration of the impaired biliary secretion, and 

 the removal as far as possible of the numerous flukes which 

 obstruct the gall-ducts, and thus add to the derangement. 

 The first object, the supply of material for the respiratory 



