8 GEORGE V SESSIONAL PAPER No. 38a A. 1918 



XI. 



SOME OBSERVATIONS ON HADDOCKS AND " FINNAN HADDIES " RELATING 

 TO THE BACTERIOLOGY OF CURED FISH. 



By Principal F. C. Hahuijsox, D.Sc, :^[ae(lonald College, P.Q. 



During the month of July, 1915, the writer whilst at the Biological Station, St. 

 Andrews, N.B., examined bacteriologically the intestinal content of twelve haddocks. 

 The haddocks were caught about a mile to two miles from the station, were brought 

 to the laboratory, opened, and a portion of the intestine ligatured and removed. An 

 opening was then cut into the piece with sterilized scissors, and a heated platinum 

 needle thrust in, and the small amount adhering to the needle was transferred to about 

 5 c.c. of sterilized water and thoroughly shaken. 



Plates were made from the dilution, from 1 to 3 cese being used for each plate. 

 Plates were made with: — 



Haddock sea water gelatine 12 per cent. 



Beef peptone sea water gelatine 12 " 



Lactose litmus sea water gelatine 12 " 



In this manner the intestinal content of twelve fish was plated, and a large 

 number of isolations made. 



At the same time a microscopical examination of the intestinal contents was made. 

 Smear preparations invariably showed numerous bacilli, mostly small forms, no cocci 

 and no spirilla. The bacterial content of the twelve fish was similar. Ten different 

 species of bacteria were isolated; of these four were liqueliers, and about 25 per cent 

 of the total number of colonies from each fish belonged to this group. Many of the 

 plates gave a strong odour of trimethylamine, and one or two of the pure cultures gave 

 this odour. In the mixed cultures, however, in the plates the odour of this substance 

 was much stronger. 



The most common organism which was found in eight of the twelve fish was a 

 small bacillus, motile, producing small depressions in gelatine plates, with numerous 

 smaller colonies around the edge, rapidly liquefying, producing H2S, indol, and trime- 

 thylamine, gas in glucose, but not in lactose, coagulating milk with digestion, and in 

 short appearing to be closely related to B. vulgaris (Hauser). 



This organism has the greater interest of all those isolated because it was found 

 subsequently in the flesh, and on the surface of smoked haddock (finnan haddie) cured 

 at the station, and also from some spoiled haddock received from a packer. 



A short account of the methods employed in securing the fish may be of interest. 



The fish were caught near the biological station, and as soon as landed they were 

 split, salted for one and a half hours in brine of sufiicient density to float the fish, and 

 smoked for eighteen hours. For six days after smoking the fish were kept in the 

 laboratoi*y at a temperature ranging from 60° to 70° F., and then pieces were removed 

 from different parts of the dried fish, each piece was thoroughly scorched and dropped 

 into flasks containing haddock sea-water peptone broth. 



Other pieces of fish were obtained thus : The backbone was cut near the tail, care- 

 fully raised, and a portion of the flesh beneath was cut out with a sterilized knife, the 

 piece seized with sterilized forceps and held in the flame until well scorched on the 

 outside, and then dropped into a culture flask. 



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