Agglittinatlon Test in Abort to ti. 

 Thus the series of tubes contain : — 



The tubes are then shaken and put in the incubator till next 

 <lay, when the results are read. Further incubation shows littlr 

 alteration, a tube showing " partial " agglutination — i.e., small 

 deposit, with no "clearing" of the supernatant fluid at the end 

 18 to 24 hours, may be complete at the end of 36 to 48 hours. 



Whey, from milk Avhich had been kept 20 days at room tempera- 

 ture, and clotted naturally, has also been tested, when it was 

 found that this bacterially-produced whey exhibited the same tit re 

 as the wliolr milk. 



A large number of experiments with whey have been performed, 

 Ijut as yet no conclusion has been come to as regards the limiting 

 titres upon which a diagnosis may be made. It has be(en found 

 that the agglutinins in Avhey increase and decrease in much the 

 same manner as they do in blood serum. The work to date has 

 been chiefly among cows on a property where the disease has been 

 in existence for a number of years, but where the abortions, since 

 the investigations commenced, have been very few — not sufficient 

 to warrant a definite opinion as to the comi3arative value of whey 

 versus serum. Sufficient has been done, however, to warrant inves- 

 tigation of the value of whey as a material for diagnosis by other 

 workers. 



b. — Collect inn of Senini from Cattle and Guiuea-iiir/s. 

 Occurretice of the Agglutinins in the Blood of Steers. 



Cattle. — Undoubtedly the most satisfactory method of obtain- 

 ing serum in large quantities is by bleeding from the jugular vein. 

 but as this method takes some time, and often necessitates the cast- 

 ing of the animal, another and simpler method is required where 

 only small quantities of blood, suflicient for diagnostic purposes, 

 are required. 



It has been found that such may be best obtained from the small 

 artery which runs with the vein extending along the centre of the 

 dorsum of the ear. This vein is the most prominent and is easily 

 found. The hair is clipped off, and an incision is made across the 

 vein and the artery at a point about mid-way betwen the tip and the 

 base of the ear. The artery may not te cut at the first incision, as 



16a 



