Manitoba Agriculture, Food and Rural Initiatives
2009 Recommendations for Administering Antibiotics to Honey Bee Colonies
Recommendations for Administering Acaricides to Honey Bee Colonies
Table of Contents Recommended and Registered Treatments in Manitoba
ANTIBIOTICS
AFB & EFB
Nosema Disease
Important
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All antibiotics and acaricides should be administered to honey bee colonies at recommended rates only.
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Never administer antibiotics and acaricides while honey supers are on the hives.
ANTIBIOTICS
Antibiotics should NOT be used to cure American Foulbrood (AFB) or European Foulbrood (EFB) that is already present in a colony. Combs with visible signs of disease should be removed from the hive and either destroyed by fire or rendered. Furthermore, it is recommended that frames from infected hives, that are not showing signs of disease, be decontaminated (see Empty Super Disinfection below), or destroyed (burnt). Following removal of the diseased combs, start an antibiotic treatment. If honey is going to be harvested from the treated colony, antibiotic treatments for AFB & EFB should stop at least 4 WEEKS before the main honey flow. Honey or syrup stored in the colony during the antibiotic treatment period should not be used for human consumption.
In the hive, AFB that is resistant to oxytetracycline (rAFB) looks the same as AFB that is susceptible to the antibiotic. Fresh rAFB, “ropey brood” and old rAFB scale may appear on the same frame. Determination of resistance to oxytetracycline requires culturing of the bacteria in a laboratory; therefore, please submit any suspicious AFB samples to the Apiculture Office in Winnipeg for resistance testing.
Currently, oxytetraycline is the only registered antibiotic for AFB control; however other antibiotics such as tylosin have been used to help control the spread of rAFB. At this time, the use of tylosin is only permitted with the recommendation from the Provincial Apiculture office and with an Off-label Use prescription from a veterinarian.
Examples of Brand Names Available: Foul Brood Mix®,
Oxytet-25-S®, Oxysol 62.5®
Active ingredient: “Oxytetracycline” (Oxytetracycline
hydrochloride)
Oxytet-25® and Oxysol 62.5® require mixing with powdered sugar prior to application. Follow the product label directions for feeding these products to honey bees (see below for Oxytet-25®).
Foul Brood Mix® is a ready-to-feed mix containing oxytetracycline, soy flour, brewer’s yeast and sucrose. Follow the product label directions for feeding this product to bees.
The following feeding recommendations for oxytetracycline are based on formulations containing 25 g of active ingredient per 454 g of product, e.g. Oxytet-25®:
Refer to product labels for instructions on specific product use. According to the label, prepare by mixing 454 g of Oxytet-25® with 3.5 kg of icing sugar (1:8 ratio by weight). Place the mixture across the frame top bars at the front or back of the hive (i.e. over the end bars). DO NOT put the oxytetracycline/icing sugar mixture over the center of the hive as it may fall down between the frames and kill unsealed brood. Given that adult bees can transmit AFB and EFB, antibiotic treatment in the spring is generally recommended even if the beekeeping equipment has had no previous disease history.
The first oxtetracycline application would generally occur within 4 days of installing the package or unpacking a wintered colony. One 454 g package will provide enough antibiotic to treat 90 spring package colonies or 45 wintered colonies.
Spring packages or small colonies should receive 14 g (1 tablespoon) of the oxytetracycline/icing sugar mixture, per colony per application, for a total 42 g per colony (i.e. 3 applications of 14 g, 4-5 days apart).
Wintered colonies should receive 28 g (2 tablespoons) of the oxytetracycline/icing sugar mixture, per colony per application, for a total of 84 g per colony (i.e. 3 x 28 g, 4-5 days apart).
In order to prevent possible contamination of marketable honey, all oxytetracycline treatments in spring or fall must occur outside the honey production season and should stop at least 4 WEEKS before the main honey flow. Honey or syrup stored in the colony during the antibiotic treatment period should not be used for human consumption!
Other methods of administering Oxytetracycline (NOT PREFERRED)
- Oxytetracycline and sugar syrup – Oxytetracycline breaks down in sugar syrup, especially when exposed to ultra-violet rays (e.g. sunlight). Therefore, feeding outside in glass jars, i.e. boardman feeders, is NOT PREFERRED. Note that approximately half of the antibiotic activity is lost by about 8 days post preparation (when kept at 30oC and out of light).
- Oxytetracycline Extender Patties – This method involves incorporating oxytetracycline into a soft patty made of shortening (e.g. Crisco®) and sugar. In this preparation, the antibiotic remains stable over a long period of time.
This method of administering oxytetracycline is NOT PREFERRED for the following reasons:
- Weak honey bee colonies often will not consume the extender patty and therefore will not benefit from the antibiotic treatment
- Leaving extender patties on colonies during the nectar flow may result in antibiotics being found in extracted honey
- This type of antibiotic application may facilitate the development of antibiotic resistance in the bacteria
Empty Super DISINFECTION
Empty supers with frames exposed to irradiation (e.g. electron beam irradiation) treatment have been shown to be effective for disinfecting AFB-contaminated supers. Pollen for bees may also be treated. For more information contact Acsion Industries at 204-753-2255, or contact Rhéal or David. Acsion Industries is located in Pinawa, Manitoba.
NOSEMA DISEASE PREVENTION
The following recommendations are for treating Nosema disease caused by Nosema apis; however another species of Nosema, Nosema ceranae has also been found in Manitoba. Current research suggests that both species of Nosema respond to antibiotic treatment but that more information is needed to determine if modifications to the Fumagilin-B® label will be required for the effective control of both species. Please note that the information below is based on the current recommendations found on the Fumagilin-B® label (Medivet Pharmaceuticals DIN 02231180 (21 mg/g)).
FUMAGILLIN Application
Brand name available: Fumagilin-B®
Active ingredient: “Fumagillin” (Bicyclohexylammonium fumagillin)
Fumagillin is available in a variety of container sizes,
depending on the brand name; therefore always follow the
product’s label recommendations. As a general guideline, 1.0 g
of fumagillin will provide enough antibiotic for treatment of
approximately 10 spring package colonies or 5 wintered colonies.
Refer to product labels for instructions on specific product
use.
Important: Medicated syrup is best prepared at a
concentration of 25 mg Fumagillin base per liter of syrup,
usually a 2:1 syrup (two parts of sugar to one part of water).
The water may be warm (20-50oC).
| Fumagillin Preparation by Bottle Size | Will Provide One Treatment For |
| Mix 0.5 g (small bottle) in 20 L of syrup | 6 spring packages or 3 wintered colonies |
| Mix 2.0 g (medium bottle) in 80 L of syrup | 21 spring packages or 11 wintered colonies |
| Mix 9.5 g (large bottle) in 380 L of syrup | 100 spring packages or 50 wintered colonies |
Colonies infected with NOSEMA should be treated with known amounts of fumagillin in sugar syrup, according to time of year and colony size/type, as follows:
FALL TREATMENT: After all honey supers have been removed, feed medicated syrup at the following rates (see above for Fumagillin Preparation):
- For each 2 chamber colony (approx. 30,000 bees): 7-8 L treated syrup (approx. 2 gal)
- For each 1 chamber colony (approx. 18,000 bees): 4 L treated syrup (approx. 1 gal)
- For each 5 frame colony (approx. 12,000 bees): 3 L treated syrup (approx. ¾ gal)
SPRING TREATMENT: In the spring when colonies are stressed due to inclement weather conditions, mite infestation, other disease factors, or intensive spring management, feed medicated syrup at the following rates (see above for Fumagillin Preparation):
- For each 2 chamber colony (approx. 20,000 bees): 3-4 L treated syrup (approx. 1 gal)
- For each 1 chamber colony (approx.12,000 bees): 2 L treated syrup (approx. ½ gal)
- For each 5 frame colony (approx. 8,000 bees): 1-2 L treated syrup (approx. ½ gal)
- For each package colony: 1-2 L treated syrup (approx. ½ gal)
Treatment with fumagillin, which may be necessary in the LATE WINTER (February-March), should follow the regime for SPRING TREATMENT (as described above).
Prior to fall feeding of colonies, it may be advisable to have combs 2, 5, 7 and 9 empty in the second brood chamber for storage of the medicated syrup.
*RESEARCH HAS SHOWN THAT Oxytetracycline & Fumagillin MAY BE FED SAFELY AT THE SAME TIME PROVIDED THE DOSAGES DO NOT EXCEED THE RECOMMENDED RATES*
For more information, contact the authors:
|
David Ostermann Manitoba Agriculture, Food and Rural Initiatives Crops Knowledge Centre Phone: 204-945-3861 Fax: 204-945-4327 |
Rhéal
Lafrenière
Manitoba Agriculture, Food and Rural Initiatives Crops Knowledge Centre Phone: 204-945-4825 Fax: 204-945-4325 |
