40 DISEASE AMONG SWINE AND OTHER DOMESTIC ANIMALS. 



eleep. As a oonsequence the animals became heated, and, perspiring, as they left their 

 lair in the morning took cold on i-oniing in contact with the chilled atmosphere. A 

 Biidden cooling, however, or a sndden reduction of the temperature of the surface 

 of the body is apt to efiect a contraction of the capillary vessels of the skin, hence a 

 diminished supply of blood, and, in consequence, a decrease or partial interruption of 

 the functions of the skin. 



The animals, thus suddenly cooled by the morning air and the wet dew, become, in 

 the course of the forenoon, again exposed to the rays of the sun and the heat of the 

 day, which induces them to go to the first pool of water, if one is accessible, to take 

 a bath. This is all right and well enough, because in the summer a hog should have 

 access to water and an opportunity to take a bath as often as it desires. In all those 

 places, however, in which the disease had made its appearance, I found the water to- 

 ■which the hogs had access almost invariably so shallow and of such a limited quan- 

 tity that the bathing and wallowing of one or more animals was sufficient to convert 

 the same into sticky, semi-fluid mud. Consequently, if the herd was a large one but 

 a very few animals — and those invariably the stronger and most active ones — had now 

 and then a chance to find clear water, and to reap real benefit from taking a bath. 

 All others, especially the younger and smaller animals, were compelled to wait until 

 the first comers were through with their bathing and had changed the water to mud ; 

 the former, therefore, had scarcely ever an opportunity to clean themselves from the 

 mud of the preceding day, and to open the pores of their skin by taking a bath in 

 clean water. If they wished to take a little cooling they had to be satisfied with taking 

 a mud-bath, and as every new bath was a mud-bath again the pores of the skin, instead 

 of being opened, became closed more and more effectually from day to day, until finally 

 the perspiration was thoroughly interrupted, and disease made its appearance as the 

 natural result. 



It is diflferent where the herd is a small one, for then nearly every animal will some- 

 times have a chance to open the pores of its skin in tolerably clear water, and the 

 perspiration will not be seriously interrupted. That these deductions must be correct 

 is proved by the fact that in every large herd nearly all the younger and weaker ani- 

 mals (shoats) have become a i)rey to the disease, while the larger or stronger and most 

 active animals, which are usually the first ones to go to the water in the morning 

 while it is measurably clear, have either remained exempt or have contracted the dis- 

 ease in a mild form, and have mostly recovered. Finally, small herds have either suffered 

 fewer losses, have been less severely attacked, or have remained exemi»ted altogether. 

 The injurious effect produced upon the system of the animal by the muddy and filthy 

 condition of the water, which most animals so situated have been compelled to drint,. 

 will be explained hereafter. 



2. Agencies and influences irhieh interfere directly tcith the process of breathing. — These,, 

 too, as already indicated, are of diflferent nature. When I first commenced my inves- 

 tigation it struck me that all those swine — pigs, shoats, and grown hogs of every age 

 and description — which run at large in the streets and thoroughfares of Kansas City,^ 

 Westport, Independence, Lexington, and other towns and villages, and lead the most 

 independent life possible, but do not congregate — go home in the evening, and belong 

 to persons who own but one, two, and maybe three animals; as also all those swine 

 "which are kept by themselves, either one by one or only a few together ; and, finally, 

 all those which are kept in comparatively small herds in pastures, orchards, or wood,^ 

 coated everywhere with grass and perfectly destitute of dusty, bare ground and oli 

 manure-heaps, are and have been, with rare exceptions, perfectly healthy. I say witl 

 " rare exceptions," for it has been reported to me that a few of those swine runninj 

 at large in the streets have died, but I have not been able to ascertain the causes of 

 their death. 



On the other hand, the herds which have been kept in yards, pastures, fields, &c, 

 consisting partially or wholly of bare, dusty ground, or containing heaps and accumiv 

 lations of old manure, have and are sutferiug severely, and the more according to th» 

 size of the herd and the worse the dust of soil and old manure. In large herds, com 

 posed of one hundred head or more, the mortality has been as high as from 70 to % 

 per cent. ; in smaller herds from 25 to 60 per cent., and where only a few animals were 

 kept together, atd consequently each animal was only compelled to inhale the dust 

 kicked up by itself and occasionally by one or two others, the mortality has been com- 

 paratively low — has seldom exceeded 10 per cent., or fatal cases have not occurred at 

 all. Further, in all those cases in which the hogs or pigs had been compelled to inhale 

 with nearly every breath a large quantity of soil and manures, ground to powder by 

 rolling, tramping, and the rays of the sun, all the jiost-mortevi examinations revealed 

 as principal morbid changes a morbid affection of the eyes, inflammation of the respira- 

 tory passages (throat, wiudpiiie, bronchial tubes), hepatization of the lungs in various 

 stages of development, and, in some cases, even tubercles or a few small abscesses in 

 the pulmonal tissue, while the serous membranes (costal and pulmonal pleura, peri- 

 cardium, and peritoneum) presented a comparatively healthy condition, except in 

 those cases in which the causes described in subdivi-iion 1 had been acting togethei 



