|
Revisiting Paraffin Dipping
in the Context of an Integrated Pest Management Approach for the Control of American Foulbrood by Jean-Pierre Chapleau Les Reines Chapleau 1282, rang 8, Saint-Adrien, Québec, Canada, J0A 1C0 apinovar@gmail.com Dipping wooden hive parts in hot paraffin has been used for many decades in New Zealand. It has been used as a means of preserving and disinfecting the material. Scientific proof of the efficiency of this sterilization method was presented by Argentinean researchers in 1998 (1). However, this technique is very little used in certain parts of the world, in North America especially. My purpose is to bring this technique back to mind as a tool in an integrated pest management approach (IPM) for bee diseases. I would also like to present to the professional beekeeping community a newly designed dipper which combines safety and efficiency. This dipper can be built by any skilled welder. The treatment of wooden beekeeping equipment with hot paraffin as part of an integrated pest management strategy for the control of American foulbrood Severe problems are being encountered with bee diseases in the United States. The situation shows that an approach of bee disease management based primarily on the use of drugs is not adequate in the long run. It is becoming very clear that we have to develop an integrated pest management approach. We have to work on increasing our bees’ resistance to disease through selection. It is also clear that we have to accept to modify our hive management practices. We need to adopt a more sensitive approach that includes additional preventive measures. Nature is showing danger signs, such as the development of antibiotic resistant strains of Bacillus larvae, which are forcing us to take new directions. I feel that the use of the paraffin dipping technique fits well into this new trend. I winter 1000 colonies that I use for queen, nuc and honey production. I have been a professional beekeeper since 1977. From the start I wanted to adopt a management that would not rely basically on medication. In fact I restrict the use of antibiotics to my queen mating nucs, and for only 3 years. I do not use drugs for my full size colonies, relying rather on focused inspections, comb rotation and other measures. I run a selection program partly aimed at developing disease resistance. Through this approach I eliminated the chalkbrood problem from my colonies many years ago. This easy success convinced me of the merits of the selection approach. I have now been working on improving hygienic behaviour since 1995. In 2001 I integrate a varroa resistance criterion into my breeding program. Selection in itself is one piece of a global strategy. Besides a battery of prevention measures, sterilization of the equipment is another essential component of an IPM approach. One problem for many professional beekeepers is the lack of a simple and efficient sterilization method at the farm level. Five years ago I realized that paraffin dipping could be a practical and cost effective way of doing the job. The good thing about it is that it provides free preservation of the equipment at the same time. Or maybe I should put that in another way? Routinely preserving your wooden hive parts with hot paraffin automatically provides preventive sterilization. Your paraffin dipper remains available at anytime for prompt disinfecting of hive parts from salvaged diseased colonies. A newly designed dipper Very few beekeepers use paraffin dipping in North America and Europe. Fewer still own a specially designed dipper. Some beekeepers dip in barrels or other improvised equipment, a practice which I do not recommend in view of the danger of using paraffin at temperatures as high as 160o Celsius. Spilling, boiling over, and spontaneous combustion are real dangers. When I decided to give this technique a serious try, I started looking for drawings of dippers. What I found at that time was either too big or too primitive. Most designs lacked important safety features. With the help of a small grant from Quebec’s Ministry of Agriculture, I designed a new dipper and had it custom-built. I then put it to work for more than 500 hours over a four year period. I incorporated improvements during the second year of use. Subsequent to my final report, the "Comité d'apiculture du Conseil des productions végétales du Québec" published a technical brochure on this technique. It contains good illustrations and detailed plans of the dipper. The text is in French but the illustrations and plans can be easily understood by non-French readers. The brochure (publication #VU028) is available right now can be ordered from: 
Here are the key features of this dipper:
The total construction cost is about $1,300 in year 2000 prices. The dipping process Here is a brief description of the dipping process. Paraffin is heated to 160o Celsius. An oven or candy thermometer can be used to check the temperature. The wooden material must be completely dry to prevent boiling out. The material is pushed gently under the surface and kept submerged for 10 to 15 minutes for complete sterilization. You also have the option of painting new hive parts, while still hot, with two coats of water-based paint. Most painted material can be dipped without problem, except for oil-based paints which will blister. The hot paraffin penetrates into the wood and seeps into joints and cracks, providing excellent protection against rotting. Safety measures Paraffin dipping can be dangerous. Here are the most important safety measures:
Cost of operation This technique is cost effective. In 1996, the cost of dipping was $0.71 per standard super compared with $1.08 for painting. These figures include labour, energy and depreciation costs. Here is a rough breakdown of these costs: labour accounts for 50%, paraffin for 30% , gas for 15% and depreciation for 5%. Do not forget that painting does not provide sterilization! 1) M. del Hoyo, M. Basualdo, E. Dedascarrasbure, A method to test the efficiency of a Disinfecting Process with Hot Paraffin for AFB Control, American Bee Journal, October 1998, pp 741-742 |
