THE APIARY.

Otago Witness, Issue 3671, 22 July 1924, Page 11

THE APIARY.

By

J. A.

DISINFECTION OF FOUL BROOD COMBS. The successful results from Dr Hutselman’s solution of formalin and alcohol m the disinfection of foul brood combs has awakened much interest in this question in the United States; and hence 1 hear of other experiments to produce like results with other disinfectants. Dr Hutselman’s results are all the more surprising, in that lie was able where the remains of dead bees still remained in the cells, and were capped over, to gat absolutely sterile results, it being proved that no mattef wliat the condition of the combs the solution was able to permeate them and prove effective. The use claimed ior the alcohol in the solution is to enable the formation to penetrate through the comb, the formalin itself being the disinfectant. The editor of Gleanings, in giving an article in the June number on “Bee Culture,” remarks: “The bacteriologist is able to grow the germs that cause American foul brood. He plants the seeds (spores) in a suitable soil (culture medium), surrounds his little garden with the proper temperature and moisture conditions, and then by moans of the microscope ho watches the growth of the tiny microscopic plants in much the same manner as a farmer tests his seed corn. This enables him to test the effectiveness of various disinfectants for killing the spores, which by growing and multiplying cause the disease. If, after soaking in the disinfectant the spores on being planted are found to grow, he knows they have not been killed; but if no growth takes place he concludes that they have. In this article Professor Jones (Professor of Bacteriology, Ontario Agriculture College) gives the result of tests of several disinfectants that have been advised for destroying the spores of American foal brood.”

The disinfectants tested by Professor Jones were izal, ehlorazene, be-helth, Hutselman's solution, and formalin. With izal, a product of coal tar, quite a number of tests were made at varying strengths, but the conclusions arrived at showed that izal is not effective in killing the spores in the scales as they are in combs. With chlorazene, described as Dakin’s new antiseptic and surgical disinfectant, the results were similar.. The scales became soft and pulpy, but even after 48 hours’ immersion good growths of B. larvae developed in all cultures. Be-heith, described as a special hypochlorite prepared particularly and only for foul brood of bees, gave similar results to tho above. After immersion for both 24 and 48 hours the scales gave good growths, showing that it also failed to kill the spores. Next on the list was Hutselman’s solution ,consisting of formalin and denatured alcohol. In this case after 48 hours’ immersion all cultures mad© from both open and capped cells remained sterile over a period of 14 days, showing that all spores had been killed. The next and last test was formalin and water mixture, and here it seems to us that some important results followed. The results were stated as follows: “All cultures made from scales from open cells of combs immersed in any of the solutions for either 24 or 48 hours remained sterile.” “Cultures made from capped cells immersed for 24 hours showed growth of B. larvaj in 20 per cent, of the cases. All cultures made from capped ceils of combs immersed for 48 hours remained sterile. The conclusions arrived at with regard to formalin water solution diluted with water, as much as 15 per cent, formalin to 85 per cent, water, is effective in destroying in 24 hours the spores of B. larvse as they occur in larvae scales in open cells.” Further, the professor says: “Although in our experiment a 43-hour immersion of the combs in the formalin and water mixtures gave us a 100 per cent, sterile result in the cultures made from capped cells, we can scarcely expect that such would always be the case, as the porosity of the cell caps varies considerably.” “In view of the fact, however, that in our experiments the formalin-water mixture gave equally good results in the destruction of B. larva? spores as the formalin-alcohol mixture known as Hutselman’s solution, we are recommending its use in 20 per cent, strength for brood combs and paper combs to Professor Miller, Agriculture Department, Ontario Agricultural College, for experiments on a large scale during the present season.” This position locks very promising for (he formalin-water solution, which should considerably reduce the cost as against the Hutselman solution, and we hope that our own Agricultural Department will not he behind in testing out the utility of the mixture. If it would render the process safer to uncap the combs, then why not do so? With a good steam knife it would not be difficult to make a tidy and clean iob of the combs. It looks like as_ if headway was at last being made in coping •with B. larvte without the necessity to destroy the frames. I suppose that where there is honey in the combs that this would require to be extracted before treatment.