Expunerea cu titlul "Tratamentele anti varroa, sănătatea albinelor şi calitatea mierii"prezentata de Dr. Zbigniew Lipinski, Varşovia, Polonia, cercetător în apicultură, specialist în patologia insectelor utile cu ocazia simpozionului Priorităţi în apicultura zilelor noastre”, Bucuresti, 6 iunie 2008, la Universităţii de Ştiinţe Agronomice şi Medicină Veterinară Bucureşti

1. ANTIVARROA TREATMENTS, HEALTH OF BEES AND QUALITY OF HONEY dr Zbigniew Lipiński POLAND

2. ANTIVARROA TREATMENTS

3. ANTI VARROA TREATMENTS HARMFUL L EFFECT OF VARROA DESTRUCTOR ON HONEY BEES HARMFULL EFFECT OF VARROA DESTRUCTOR ON BEES

4. HARMFULL EFFECT OF VARROA DESTRUCTOR ON HONEY BEES

5. Varroa mites not only cause significant damage to the bees by feeding on their hemolymph, but also act as a vector for viral diseases like Acute Paralysis Virus (APV) and Chronic Paralysis Virus (CPV). The wounds inflicted by mites may also be contaminated with bacterial or fungal organisms. These secondary infections can be recognized based on typical symptoms associated with them and often lead to severe damage to the colony. In order to prevent this, it is crucial that colonies are monitored for Varroa infestation regularly and that measures to control the infestation are taken when necessary De forming bee wing virus

6. TYPICAL MITE POPULATION DYNAMICS FOR A TEMPERATE CLIMATE

7. The main battle with varroa Recognition through fight

8. Unchecked, varroa can really multiply! A 12-fold increase is typical in a short season consisting of 128 days of brood rearing (Martin 1998). However, its population can increase 100- to 300-fold if broodrearing is continuous! (Martin and Kemp 1997).

9. Varroa Population Dynamics

10. UP TO NOW MOST BEEKEEPERS HAVE APPLIED SYNTHETIC PESTICIDES (ACARICIDES – VARROACIDES) TO CONTROL THIS MITE IN THEIR COLONIES.

11. LIST OF TREATMENTS SHOWN TO HAVE SIGNIFICANT EFFICACY FOR VARROA CONTROL Product Trade Name Active Ingredient Chemical Class Apiguard thymol essential oil Apilife VAR thymol, eucalyptol, menthol, camphor essential oil Apistan fluvalinate synthetic pyrethroid Apitol cymiazole iminophenyl thiazolidine derivative Apivar amitraz fornamidine Bayvarol flumethrin synthetic pyrethroid Check-Mite+, Perizin coumaphos organophosphate Folbex bromopropylate chlorinated hydrocarbon generic formic acid organic acid generic lactic acid organic acid generic oxalic acid organic acid

12. THE USE OF SYNTHETIC ACARICIDES HAS THREE MAJOR DISADVANTAGES 1 – INFLUNCES BEE HEALTH KNOWN AS ADVERSE EFFECTS 2 – CONTAMINATES HONEYBEE PRODUCTS 3 – CAUSES VARROA RESISTANCE

13. HEALTH OF BEES HEALTH OF BEES & SYNTHETIC ACARICIDES

14. ADVERSE EFFECTS CAUSED BY THREE MOST COMONLY USED SYNTHETIC ACARICIDES FOR CONTROL OF VARROA FLUVALINATE FLUMETHRINE AMITRAZ

15. Increased adult bee mortality for fluvalinate has been assessed at 2.7 bees/day over 60 days 52 . Significantly less (86% vrs. 97%) drones emerged from colonies treated with Apistan than control colonies, but survival was greater for both compared to varroa infested colonies (59%). Both varroa and Apistan caused reductions in drone body weight and various glands 125 In queen cages, exposure to 1% fluvalinate for 3 days caused significant mortality in worker attendants and increased supersedure in queens. Exposure for 7 days caused significant mortality in queens 31 . FLUVALINATE A DVERSE EFFECTS

16. Three experiments were conducted on queen and worker honey bees (Apis mellifera L) to assess effects of treatment with fluvalinate impregnated (Apistan ® ) strips. A 5-d treatment of worker bees (weighing 1.4 kg per group) in screen packages with a fluvalinate strip (2.5% a i, 2.5 x 13 cm) did not increase mortality. Overwintered laying queens (n = 30), and newly mated queens (n = 60) were treated in Benton mailing cages for 5 d with fluvalinate (Apistan Queen Tabs, 1% a i, 2.5 x 1.3 cm). All queen mortality occurred on d 4 and 5 of the treatment period, which is beyond the recommended 3-d-treatment. Neither group of treated queens exhibited a significant increase in mortality. However, attendant worker bees in the second trial exhibited a significant increase in mortality during treatment . No differences were observed in colony acceptance of queens, brood viability, or supersedure rates at 2 and 6 months post-exposure.

17. FLUMETHRINE A DVERSE EFFECTS No increase in bee mortality was observed in a field study of honey bee tolerance to the chemical, and was the lowest of 6 chemicals tested 52 .

18. A preparation of amitraz (Apivarol) was found to increase mortality of 1-3 day old larvae (61% vrs. 83% for control) 4 . A fumigation strip of amitraz caused some bees to leave their hive and form clusters 98 . Fumigation strips also caused high adult bee mortality in package bees 60 . AMITRAZ A DVERSE EFFECTS

20. THERE ARE ALSO ADVERSE EFFECTS CAUSED BY THREE LESS COMONLY USED SYNTHETIC ACARICIDES FOR CONTROL OF VARROA CYMIAZOLE COUMAPHOS BROMOPROPHYLATE

21. CYMIAZOLE A DVERSE EFFECTS Adult bee deaths have been reported with Apitol 61; 45 . Cymiazole was found to be moderately toxic to honey bees when ingested at a rate of 3500ppm 119 . Cymiazole fed to bees reduced development of hypopharyngeal glands and increased the amount and acidity of rectal contents 118 .

22. COUMAPHOS A DVERSE EFFECTS Increased adult bee mortality for Perizin has been assessed at 15.7 bees/day over 7 days 52 . Perizin was assessed as having a low toxicity for bees (LD50 = 14.39µg) 7 8 .

23. Use of Folbex did not cause adverse effects on queen lifespan, brood area or honey production 7 . Folbex did not affect brood survival compared to controls BROMOPROPHYLATE ADVERSE EFFECTS

24. ADVERCE EFFECT CAUSED BY ESSENTIAL OILS THYMOL EUCALIPTOL MENTHOL CAMPHOR APILIFE VAR

25. THYMOL A DVERSE EFFECTS Increased adult bee mortality for thymol has been assessed at 9.5 bees/day over 10 days 52 , although in another study only young larvae survival was affected (74-87% v. 89-95% for controls), with no differences in sealed brood or adult survival 102 .

27. APILIFE VAR A DVERSE EFFECTS Colony development is not thought to be impaired by use of Apilife VAR 91 , although one study reported loss of 50% of bees in treated colonies over winter, and significant reductions in honey crops the next year 112 . Colonies are reported to have problems storing winter feed during Apilife VAR autumn treatment 67 .

28. ADVERCE EFFECT CAUSED BY ORGANIC ACIDS FORMIC ACID LACTIC ACID OXALIC ACID

29. FORMIC ACID A DVERSE EFFECTS Use of Formic acid gel resulted in removed drone eggs, delayed drone production and reduced adult drone survival (24% survival at 10 days old vrs. 49% for controls). Unlike fluvalinate, formic acid did not reduce drone weight or weight of glands Surviving drones had higher levels of sperm than controls 33 . Formic acid may also have adverse effects on open brood and hatching bees, depending on ambient temperature and device used, although loss of brood did not have a negative effect on colony overwintering in mid-European conditions 92 . Formic acid produced the highest rate of adult bee mortality (35.3 bees/hive/day) of 6 substances tested 52 . .

30. LACTIC ACID ADVERSE EFFECT Lactic acid sprayed on combs at 8ml/dose caused bees to remove 60% of eggs 86 . In another experiment, bee mortality increased 4-fold for 2 days following treatment, but then returned to normal 84 . However, this may have been related to poor dosage control, since a precise dosage did not produce any adverse effects significantly different than coumaphos treatment, either in the autumn or the next spring 87 . Bee mortality was much lower for lactic acid (1.1 bee/hive/day) compared to formic acid (35.3 bees/hive/day) 55 .

31. OXALIC ACID ADVERSE EFFECT Long term (4) spray applications of 3% oxalic acid in autumn and spring showed significantly negative effects on brood development and queen survival 62 , although other studies did not show such effects 114; 19 . Trials also suggest that some hives show adverse effects from oxalic acid syrup treatment 29 . The results indicate that OA has a low acute toxicity to honey bees and a high acute toxicity to mites. Alliano et al. 2006

32. OA is extensively used without knowing the basic toxicological properties of the compound to V. destructor or A. mellifera. The results indicate that OA has a low acute toxicity to honey bees and a high acute toxicity to mites. Alliano et al. 2006 BY THE WAY

34. QUALITY OF HONEY

35. QUALITY OF HONEY DERRIVATE OF COMB CONTAMINATION

36. Council Regulation 2377/90 lays down a Community procedure to harmonise MRLs among Member States As a consequence of the Regulation the following restrictions are imposed on the production of honey: An MRL is the maximum concentration of residue following administration of a veterinary medicine which is legally permitted or acceptable in food under the laws of the EU .

37. Annex I: Final MRLs The data in the dossier are considered adequate to establish a final MRL. (amitraz, cymiazol, coumaphos) Annex II: MRLs not necessary The data in the dossier demonstrate that there is no risk to the consumer and MRLs are not needed. (camphore, flumethryne, fluvalinate oxalic Acid, formic acid, thymol Annex III: Provisional MRLs This is for medicines where MRLs can be established but some clarification of further studies are required before final MRLs can be set. Annex IV Residues of the medicine pose an unacceptable risk to the consumer or there is insufficient information to allow a full assessment. The products in Annex IV are prohibited for use in food producing animals in the European Union. EU REGULATIONS

38. • For honey MRLs have been fixed for coumaphos and amitraz , which are allowed in honey up to a limit of 100 and 200 parts per billion ( ppb) respectively . This means that these substances are allowed to be present in honey, as long as the concentrations remain below these limits (see also Annex I of the Regulation). • Provisional MRLs for pharmacologically active substances used in veterinary medicinal products. For these residues there are no grounds for supposing that residues at the level proposed present a health hazard for the consumer. In the case of honey it concerns only cymiazole which is allowed to be present in honey up to a limit of 1000 ppb (see also Annex III of the Regulation).

39. Commission’s decision, made on Dec. 9 and 10, 2003 in London, which included oxalic acid for use with bees in Annex II of the Council Regulation (EEC) 2377/90 (as was already the case for formic acid, lactic acid and thymol). That means that no maximum limit exists for oxalic However, this does not mean that beekeepers are allowed to use an inappropriate amount of oxalic acid in treating their bees, thereby causing high amounts of residue in their honey. According to European honey standards, honey may have up to 50 milliequivalents of free acids. If higher residues of oxalic or other acids are produced, this limit is soon exceeded, and the beekeeper risks having problems if his honey is checked by authorities. If oxalic acid is used properly, there is absolutely no risk of problems with the honey. OXALIC ACID AND OTHER ORGANIC ACIDS

40. RESISTANCE “ the ability of an organism to tolerate toxic doses of a substance that would be lethal to the majority of individuals in a normal population of the same species” (Watkins 1996). In effect, resistant mites are selected for, at the same time the susceptible ones are being selected against (Eischen 1995) ). This resistance (to a pesticides for example) is genetically transmitted to offspring from the parents and is not generated spontaneously as a chemical treatment is applied, the characteristic already exists in the population (Eischen 1995).

45. First cases of varroa* resistance to most popular acaricides found in Europe and north America Miticide Country Authors A Amitraz Serbia Duijn et al. (1991) B Amitraz USA Elzen et al. (1999,2000) A Cumaphos Italy Spreafico et al. (2001) B Cumaphos USA Pettis (2004). A Fluvalinate / Flumethrine Italy Milani (1993) B Fluvalinate / Flumethrine USA Elzen et al. (1999)

46. HOW TO HANDLE WITH THE VARROA PROBLEM IN THE FIELD – IN GENERAL IN HEAVILY INFESTED AREAS (huge winter deaths) IN SLIGHTLY INFESTED AREAS (Normal winter deaths) THE MOST IMPORTANT IS PRECISE KNOWLEDGE OF THE: 1 - LEVEL OF RESISTANCE TO USED SYNTHETIC ACARICIDES ( ptretroids, amitraz ) 2 – THE NUMBER OF VARROA LEFT ON BEES AFTER THE TREATMENT Laboratory trial for pyrethroide resistance – obligatory Laboratory trial for pyrethroide resistance – not obligatory MODE OF ACTION 1 - High risk of resistance or full resistence - Hive Clean VERY USEFULL + ban on nucs 2 - No resistance – all official medicines allowed. Hovewer type of medicine indicates the manner of combat with varroa. 3 – Movement into heavilly infested areas – in each case use of Hive Clean especially during fall change of bee generation – e.g. late buckweet.

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