CLINICAL EVIDENCE OF VALUE OF SERUM 481 



call our attention to the advisability of dividing our hogs up into 

 small droves, rather than allowing them to all range together in 

 the one herd. It is a little more inconvenient to handle them in 

 two or three droves, but the advantages of this arrangement in case 

 of an outbreak of cholera are so great that it would apparently well 

 repay for the additional amount of care which would be necessary 

 in handling them in the separate feed lots. 



In the case of the old sow, that died apparently from an infec- 

 tion received during the administration of the treatment, we have 

 impressed upon our minds the importance of the most extreme 

 care in handling the animals at time of treatment. Serum needles 

 and syringes must be kept absolutely clean, and every possible 

 source of infection guarded against. Otherwise, there are bound to 

 be losses that could probably have been prevented. An occasional 

 accident of this nature is Uable to happen even with the most 

 careful operators, but the danger is much increased if the serum be 

 given by an incompetent man. 



Herd Number Twenty-Nine. — The twenty-ninth of these ex- 

 periment herds was located in the northwest quarter of Section 

 2, Jackson Township, Boone County, Iowa. Boone County closely 

 adjoins Story County, but this herd was some distance from the 

 herds which have already been described. This drove was also 

 a pure-bred herd, being composed of full-blood Chester-Whites 

 of various ages and sizes. 



When this herd was first visited by the Bureau of Animal 

 Industry representatives on October 22, 1907, several of the shoats 

 on the farm were sick. The disease had been present for some 

 time, as the first sick hogs had been noticed several days previous. 

 The disease made its first appearance among the gilts and barrows. 

 There were a number of young boars in the herd, but they were 

 kept in a separate feed lot, some distance from the balance of the 

 herd, and were apparently well on the daj' of treatment. 



As there was no cholera in the immediate neighborhood of this 

 farm, it was impossible to secure any definite history as to just 

 how the disease had reached the herd. 



The animals which were sick at the time the farm was visited 

 showed the usual symptoms of hog-cholera — they remained in 

 their nests, did not eat, were weak in the hind legs, and had some 



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