■210 ON THE OCCURRENCE OF " WORM-NODULES " IN CATTLE 



examination would possibly show that fifty per cent, is a 

 nearer approximation. He instances a case in which ten 

 per cent, were found to be infected after "very careful 

 examination by manipulation, using incision only when 

 certain or doubtful, but later on, when the brisket of a num- 

 loer were partially dissected, another 25 per cent, were 

 found to harbour the nodules." Thus 35 per cent, of the 

 cattle, from a " notoriously clean station," from the south- 

 western portion of Queensland, were parasitised by 

 Onchocerca gihsoni. In two mobs, from different parts of 

 north-western Queensland, the same observer detected 

 their presence in 60 per cent, of the animals " without any 

 manipulation," and as a result of " a more careful examin- 

 ation by dissection," found every animal to contain " from 

 one nodule upwards." It is known that the heaviest in- 

 fection occur in the more northerly districts, and that the 

 degree lessens as we pass southward. Gilruth and Sweet 

 believe that this state of affairs is not due to the conditions 

 of "soil, climate, rainfall or management." Gibson (1893, 

 p. 577) mentioned that he had been informed by Mr. Stanley, 

 the New South Wales Government A^eterinarian, that at 

 least 50 per cent, of the cattle slaughtered about that 

 time (1892) in Sydney, contained Avorm-nests, but Gilruth 

 and Sweet (p. 3) doubt this large percentage. Our own 

 experience did not reveal such a high degree of infection. 

 Hancock (1911, p. 25) states that "since examination has 

 been systematically made, at least 50 per cent, of all con- 

 signments from Queensland ports have been found to contain 

 a variable percentage of affected carcases." Judging from 

 ^-ilruth and Sweet's findings, Hancock's estimate Avould 

 be greatly increased if a more searching examination were 

 carried out. The Editor of the British Medical Journal 

 (3rd Dec, 1910, p. 1797), mentioned that about 75 per cent, 

 of the carcases were found to be parasitised. MacfaddeT\'s 

 findings (1911,, p. 2) corroborate those of Gilruth. He stated 

 that at first ten per cent, of the quarters in each consignment 

 mere examined for the presence of nodules, but on a more 

 complete examination, it was noticed that a much larger 

 percentage was infected, and in some instances " as many 

 as a hundred per cent, of those already passed " were found 

 to contain worm nests. The Editor of the Journal of Meat 

 and Milk Hygiene (1911, p. 23), in a footnote to our paper 



