APIVAR DRAMATICALLY CUTS MITE POPULATION
A study1 conducted by the research arm of the USDA in the spring of 2012 shows that Apivar® was responsible for a 52-fold drop in mite population compared to an untreated hive. This demonstrates the effectiveness of Apivar’s controlled-release technology.
APIVAR STRIPS SAVE TIME AND EFFORT
Apivar is packaged in vacuum-sealed foil pouches that each contain 10 strips. A single application of two strips per brood chamber is sufficient to treat a hive, so you spend less time and effort treating your bees, and there is less disruption of the bees than with many other treatments. Separate the double strip and place each strip in the brood chamber near bee cluster, two frames apart and between the frames so the bees can walk on both sides of the strip. Leave in for 42 days minimum. If the bee cluster moves away from the strips, reposition the strips into the bee cluster and leave on for an addition 14 days. Strips must be removed after a maximum of 56 days. Do not reuse the strips. Wait 14 days after removing the strips before placing honey supers on the hive.
1 Eischen et al, Controlling Varroa destructor with APIVAR –– Spring 2012 field trial, Honey bee research unit USDA-ARS, Weslaco, TX.
1. Why treat against Varroa mites?If you don't treat a colony that is infested with Varroa mites effectively, you are condemning it to certain death, within a year in many cases.These mites weaken the bees by feeding off their haemolymph (blood). Bees become far less resistant to other diseases, their lifetime is greatly shortened and their wings become atrophied. Fewer forager bees can fly to find pollen and nectar to feed larvae in the brood, and weakened, their return flight to the hive becomes more and more difficult. The colony produces less and less honey and becomes unable to feed the new bees, which causes the weakness (in spite of the laying activity of the queen) then the colony collapses.Moreover, it has been proven that the higher the rate of infestation, the shorter the duration of life of honey bees. That is a real issue for wintering bees that are infested during their development and not able to go through winter and take part in colony development in spring.
Treating against Varroa mites is a matter of bees and colony survival. The goal is to lower the infestation rate to a threshold that can be sustainable for colony development and survival in winter.
Varroa destructor is a real plague for the honey bees and beekeepers in a majority of countries all over the world. Its control is a matter of global concern of the worldwide beekeeping industry.
2. What is Apivar, and how does it work.
Apivar strips are made of two components:
Amitraz is an acaricide. It does not kill mites directly, but is rather considered as a sub-lethal miticide with an original mode of action from neurotoxicity type, different from other current Varroacides. Acting on the synaptic transmission of mites, it leads to constant excitation and paralysis, followed by mite drop from the bee's back. Secondarily, Varroa dies due to starvation as a result of this paralysis. Amitraz acts by contact only.
A plastic polymer specially chosen for its rigidity and to allow a slow and continuous release of amitraz during many weeks.
Apivar strip has been designed to release the active ingredient, from the opening of the pack, as soon as it is put into the hive. Amitraz is available on the surface of the strips for the bees that come in contact. The active ingredient is spread into the colony from one bee to another by contact. After a short period of time, amitraz is hydrolyzed and disappears from the hive.
Mode of action into the hive
Legend:1. Amitraz is available at the surface of the strip in the hive2. Honey bees in contact with the strips pick up the active ingredient (no diffusion into the hive by evaporation)3. By contact, honey bees can transfer the amitraz within the colony4. Amitraz is quickly hydrolyzed and disappears from the hive. (cf FAQ residues)
Merrington, O (1990). Bibliography on the Use of Amitraz for Varroa Control in Bees (Apis spp.) (1979-1989). Cambridge, UK, Cambridge Animal and Public Health Ltd. 36pp.
Varroa mites were first reported in Kentucky in the Bluegrass region of the Commonwealth in 1991. They have spread to and become a major pest of honey bees in many states since their introduction into Florida in the mid 1980's.
Varroa mites are external honeybee parasites that attack both the adults and the brood, with a distinct preference for drone brood. They suck the blood from both the adults and the developing brood, weakening and shortening the life span of the ones on which they feed. Emerging brood may be deformed with missing legs or wings. Untreated infestations of varroa mites that are allowed to increase will kill honeybee colonies. Losses due to these parasitic mites are often confused with causes such as winter mortality and queenlessness if the colonies are not examined for mites.
The adult female mites are reddish-brown in color, flattened, oval, and measure about 1 to 1.5 mm across. They have eight legs. They are large enough to be seen with the unaided eye on the thorax, most commonly, and on the bee's abdomen. Their flattened shape allows them to hide between the bee's abdominal segments. This mite is often confused with the bee louse, but the bee louse has only six legs, is more circular in shape, and is slightly larger.
Mites develop on the bee brood. A female mite will enter the brood cell about one day before capping and be sealed in with the larva. Eggs are laid and mite feed and develop on the maturing bee larva. By the time the adult bee emerges from the cell, several of the mites will have reached adulthood, mated, and are ready to begin searching for other bees or larvae to parasitize. There is a preference for drone brood. Inspection of the drone brood in their capped cells will often indicate whether or not a colony is infested. The dark mites are easily seen on the white pupae when the comb is broken or the pupae are pulled from their cells.
Mites spread from colony to colony by drifting workers and drones within an apiary. Honey bees can also acquire these mites when robbing smaller colonies. It is best to isolate captured swarms, package bees, and other new colonies from other colonies and examine them for mites before placing them in an apiary.
Early detection of low levels of mite infestations is key to its successful management. While they can be spotted during colony inspection if present in high numbers, this tends to only identify larger infestations. There is a product available, Apistan, that will kill the mites and cause the mites to drop from the bees. Two strips should be hung in the brood nest area of the colony for approximately 4 weeks. This is to be used with sticky paper and a fine-mesh screen on the bottom board of a colony to capture any mites that may have been present. A considerable amount of cell cappings and other debris will also collect on the sticky paper, so it is best to inspect the sticky paper carefully for mites after removal. This method is able to detect low level infestations. Apistan strips are available from most of the large beekeeping suppliers and can be used both for detection and treatment of varroa infestations.
If a colony is found to be infested, all colonies at the site should be treated for mites with Apistan strips in the same manner. These strips contain the miticide fluvalinate and are not to be used during honey flow, or when there is surplus honey present in the colony that may be removed for human consumption at a later date. Therefore, late fall, after removal of surplus honey, or early spring, prior to honey flow, are the best times to treat for varroa mites.
Always carefully follow all label instructions with regard to the storage, use and disposal of pesticides.
3. What is the effect of high and low temperatures on the treatment efficacy?Spread of amitraz into the colony is the result of the contact between the honey bees and the strips. As a consequence, this diffusion is not directly linked to the external temperature. This mode of action is different from other devices used to treat against Varroa such as thymol-based products whose diffusion by vaporization changes in relation to the hive's atmosphere. This diffusion is blocked at a low temperature or dangerously increased at a very high temperature.
Regarding amitraz, temperature has no effect on the product itself. Nevertheless, we can consider that at low temperature, activity of bees is lowered and contacts with the strips can decrease.
In the apiary: If the situation requires a treatment, strips can be put into the hive as soon as hives become active after the winter or just after the honey collection and withdrawal of supers during summer.
4. When should I treat my hives with Apivar?You may use the product all year round, but as an additional safety factor for the good image of honey, it is recommended to not use Apivar when the honey supers are present: - After harvesting, towards the mid or end of the Summer - "Autumn Treatment" - Before the nectar collecting period in the Spring - "Spring Treatment"
Treatment after the last usable honey flow - Autumn Treatment.The aim of the autumn treatment is to decontaminate the colony before winter bees are produced and is considered the most important treatment in most beekeeping systems to prepare the colony for a good wintering, in addition with correct feeding when needed.
It should be initiated as soon as honey supers are removed
when the nurses of winter bees are developing so that their breeding capacities can be maximized.
before the parasites have had time to harm the colony
In the apiary: Put the strips into the hive just after the honey supers are removed.
Spring TreatmentThe aim of the spring treatment, with the removal of the strips before adding the honey supers, is to decrease the mite populations before honey collection and to be sure that there will be no risk of colony collapse during the season up to the Autumn treatment and to maximise honey yield.Varroa mites can be most quickly and easily eliminated when the least amount of brood is present.
5. What is the recommended dosage and why?The recommended dosage is 2 strips per brood chamber (or 1 strip per 5 frames of bees).Apivar was tested on the basis of a precise dosage and specific use directions, therefore these should be followed to obtain the best performance.
Under-dosage may lead to poor efficacy and be critical for the colony survival until the next varroa treatment.
An excessively low concentration may cause the parasites to become resistant to the active ingredient. That could be the case if only one strip was inserted, if old strips were re-used or if strips were not removed after the treatment period.
6. Is it recommended to treat at the same time as feeding?There is no contraindication to feed and treat at the same time. Apivar does not effect feeding. On the contrary, it can be easily thought that the two activities are synergistic to fight against Varroa mite:
Feeding increases activity in the colony and probably the contact of bees with the Apivar strips. So it can be considered as a good way to increase the speed of decontamination.
Feeding has the same goal as Apivar treatment, to reinforce the colony for the winter season. As a consequence feeding and treating at the same time can be regarded as good preparation for the wintering period.
In the apiary: Do not hesitate to treat with Apivar and feed honey bees at the same to time to prepare for the winter.
7. Can I treat whenever I want during the year?From a regulatory point of view, Apivar can be used all year round. Nevertheless, in accordance with good beekeeping practice, we recommend to treat when honey supers are not present. This would be the best way to convey a good image for honey as a natural product. As a consequence, strips should be removed before the main nectar-collecting period in the spring and can be placed into the hive after harvesting during summer.
8. Can I treat in the presence of brood?It is recommended to treat when there is some brood in the colony and that is one of the major assets of a long-release treatment such as Apivar in treating against Varroa.The strips release amitraz for many weeks. As a consequence, treatment is effective for several reproduction cycles of the Varroa mite and can be more effective for decontamination of the colony.It is very important to position the strips in an area of high activity and nearest to the Varroa breeding area (in the brood).Nevertheless, when there is no brood in the hive, treatment is also effective.In the apiary: First of all, locate the brood area, then place 2 strips between the frames with a minimum distance of 2 frames between strips.
9. Recommendations for high efficacy of ApivarAs Apivar is a medicine, you should read and follow the directions of use.
Positioning of the strips.Apivar works by contact only. It is therefore very important to position your strips in an area of high bee activity, and nearest to the Varroa breeding area in the brood area.This ensures that many bees will be in regular contact with the strips in order to give effective distribution of the Amitraz throughout the hive.Ideal positioning is to hang up each strip between 2 frames inside the brood area with a minimum distance of 2 frames between strips.
Respect the recommended dosage.The recommended dosage is 2 strips per brood chamber. Apivar was tested on the basis of a precise dosage and specific direction for use. The recommended dose on the label should be followed to obtain the best performance.
Treating all the hives at the same time:Adult Varroa mites attach themselves to adult bees. They spread when hives are robbed, when drones move from one hive to another, and even, according to some researchers, when pollen is gathered through foraging bees. Hive member exchanges, meeting of colonies, artificial swarming and even bee shipments and purchase may infest a hive that has previously been healthy. To avoid this, check your hives regularly and treat all of them if you see any infestation.
Checking strips position after a few weeks.Sometimes, during the Autumn treatment, the brood area can slowly move. As a consequence, a few weeks after the beginning of the treatment, the strips of Apivar are no longer amongst the brood. This situation can decrease the efficacy of the treatment by lowering the number of contacts between bees and strips.It is recommended to check the position and to correct if necessary. In this case it can be appropriate to lengthen the treatment by 2 additional weeks.
Remove the strips at the end of treatment.Strips should be removed at the end of the treatment for 2 main reasons:
At the end of treatment, after a long releasing process, the quantity of amitraz released by the strips is lower. This creates favourable conditions for resistance development.
Apivar strips are not biodegradable. Product should be disposed of in a registered local body landfill (i.e. local rubbish collection).
Strips should not be reused.
10. What to do when strips are covered by propolis?This is very rare. Our recommendation will be to remove the propolis from the surface as it prevents bees from having real contact with the strips and lowers the diffusion of amitraz.In the apiary: Scratch the strips with a hive tool when there is too much propolis. In this case, it can be appropriate to lengthen the treatment a few additional days.
11. How long can strips be kept after opening the sachet?Apivar packs are sealed under vacuum to ensure a good preservation of the strips and the best quality. So, to guarantee a high concentration of amitraz, strips have to be used as soon as possible after opening.In the apiary: It is recommended not to prepare strips the day before their installation into the hives.
12. What is recommended after removal?After removal the strips should be disposed of in a registered local body landfill (i.e. local rubbish collection).
13. Is there a monitoring of the efficacy of Apivar? Is the efficacy still very good despite the frequent use of Apivar?In the EU where it has been developed, Apivar is classed as a veterinary medicine and is subject to the medicine regulations. As a consequence, Apivar benefits from a full market authorization dossier with efficacy data that shows its efficacy to reduce Varroa mite infestation.Since it has been authorized, many trials have been carried out on a regular basis to monitor its efficacy. For example, in France, where Apivar is authorized and used on a large scale since 1995, Veto-pharma takes part every year in an efficacy study. The efficacy of Apivar remains very high despite a very intensive and repeated use for many years in a lot of countries worldwide.
Trials have also been conducted in the US and Turkey in 2009, and in Bulgaria in 2011. All the results are consistent and show a constant efficacy.
14. Is Apivar submitted to residues trials?The French laboratory of ANSES in Sofia Antipolis, is the reference lab for the European Union for honey bee health. It has conducted a residue trial in 2007 whose results are consistent to previous ones:
No residue of Amitraz was detected in honey after 10 weeks of treatment, regardless of the date of sampling. This is due to the instability of the active ingredient in an acid environment. Other studies have also proved that the amitraz is fully degraded after 10 days in honey.
No residue of amitraz in wax after 24h after the removal of the strips.
This publication also studied residues of coumaphos in honey and wax with less satisfactory results.Other studies concluded that quantities of residues of amitraz or its main metabolites in honey are always under the MRL.
Ref: Martel A.C. et al, Acaricide residues in honey and wax after treatment of honey bee colonies with Apivar or Asuntol 50, Apidologie (2007), 38, 2002, 534-544Ref : R.M. Goodwin et al, Residues of amitraz in wax honey and propolis after using Apivar, 2002
15. Is Amitraz more toxic than pyrethroids?Apivar is authorized in several countries thanks to a complete Market Authorization Dossier that includes safety data.
Two types of toxicity have been assessed:
Toxicity for the bees.A study applying Amitraz at a dosage 5 times more than that recommended, shows no effect on honey bees, queens and brood.
Toxicity for human beings.This safety is controlled with the MRL system that fixed a maximum limit of residues that are allowed into products dedicated to human consumption. Many residues studies have proved that the residues of amitraz and its main residue are always lower than this threshold which is 200 ppm (200 mg per ton of honey).This good situation is due to the high instability of amitraz and its quick hydrolysis.
As a consequence, it can be said that amitraz is safe when it is used in accordance with recommendations (dosage, treatment duration...)
Ref: Martel A.C. et al, Acaricide residues in honey and wax after treatment of honey bee colonies with Apivar or Asuntol 50, Apidologie (2207), 38, 2002, 534-544
On the contrary pyrethroids (like fluvalinate) are more stable in wax. Some studies show that the level of residues of this product is higher for a longer time than those of amitraz's. The risk of residues in honey is more likely with these type of actives.
Ref: S. BOGDANOV et al, ACARICIDE RESIDUES IN BEESWAX AND HONEY, (1997)Ref: K. WALLNER, Varroacides and their residues in bee products, Apidologies 30 (1999) 235-248